@article {3870, title = {High-affinity binding of celastrol to monomeric α-synuclein mitigates in~vitro aggregation.}, journal = {J Biomol Struct Dyn}, year = {2023}, month = {2023 Feb 06}, pages = {1-11}, abstract = {

α-Synuclein (αSyn) aggregation is associated with Parkinson{\textquoteright}s disease (PD). The region αSyn acts as the nucleation {\textquoteright}master controller{\textquoteright} and αSyn as a {\textquoteright}secondary nucleation site{\textquoteright}. They drive monomeric αSyn to aggregation. Small molecules targeting these motifs are promising for disease-modifying therapy. Using computational techniques, we screened thirty phytochemicals for αSyn binding. The top three compounds were experimentally validated for their binding affinity. Amongst them, celastrol showed high binding affinity. NMR analysis confirmed stable αSyn-celastrol interactions involving several residues in the N-terminus and NAC regions but not in the C-terminal tail. Importantly, celastrol interacted extensively with the key motifs that drive αSyn aggregation. Thioflavin-T assay indicated that celastrol reduced αSyn aggregation. Thus, celastrol holds promise as a potent drug candidate for PD.Communicated by Ramaswamy H. Sarma.

}, issn = {1538-0254}, doi = {10.1080/07391102.2023.2175379}, author = {R, Kavya and Aouti, Snehal and Jos, Sneha and Prasad, Thazhe Kootteri and K N, Kumuda and Unni, Sruthi and Padmanabhan, Balasundaram and Kamariah, Neelagandan and Padavattan, Sivaraman and Mythri, Rajeswara Babu} } @article {3717, title = {Systematic review of articular cartilage derived chondroprogenitors for cartilage repair in animal models.}, journal = {J Orthop}, volume = {35}, year = {2023}, month = {2023 Jan}, pages = {43-53}, abstract = {

PURPOSE OF RESEARCH: The potential for cartilage repair using articular cartilage derived chondroprogenitors has recently gained popularity due to promising results from in-vitro and in-vivo studies. Translation of results from in-vitro to a clinical setting requires a sufficient number of animal studies displaying significant positive outcomes. Thus, this systematic review comprehensively discusses the available literature (January 2000-March 2022) on animal models employing chondroprogenitors for cartilage regeneration, highlighting the results and limitations associated with their use.As per Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, a web-based search of PubMed and SCOPUS databases was performed for the following terminologies: "chondroprogenitors", "cartilage-progenitors", and "chondrogenic-progenitors", which yielded 528 studies. A total of 12 studies met the standardized inclusion criteria, which included chondroprogenitors derived from hyaline cartilage isolated using fibronectin adhesion assay (FAA) or migratory assay from explant cultures, further analyzing the role of chondroprogenitors using in-vivo animal models.

PRINCIPAL RESULTS: Analysis revealed that FAA chondroprogenitors demonstrated the ability to attenuate osteoarthritis, repair chondral defects and form stable cartilage in animal models. They displayed better outcomes than bone marrow-derived mesenchymal stem cells but were comparable to chondrocytes. Migratory chondroprogenitors also demonstrated superiority to BM-MSCs in terms of higher chondrogenesis and lower hypertrophy, although a direct comparison to FAA-CPs and other cell types is warranted.

MAJOR CONCLUSIONS: Chondroprogenitors exhibit superior properties for chondrogenic repair; however, limited data on animal studies necessitates further studies to optimize their use before clinical translation for neo-cartilage formation.

}, issn = {0972-978X}, doi = {10.1016/j.jor.2022.10.012}, author = {Vinod, Elizabeth and Padmaja, Kawin and Ramasamy, Boopalan and Sathishkumar, Solomon} } @article {2885, title = {An Amphiphilic Double-Brush Polymer Hydrogel for Sustained Release of Small Molecules and Biologics: Insulin Delivering-Hydrogel to Control Hyperglycemia}, year = {2022}, doi = { https://doi.org/10.1002/cnma.202200184}, author = {Dhayani, Ashish and Bej, Sujoy and Mudnakudu-Nagaraju, Kiran K and Chakraborty, Saheli and Srinath, Preetham and Kumar, Ashok H and PS, Ann Maria and Kristi, Anand and Ramakrishnan, S and Vemula PK} } @article {2504, title = {Assessment of the inherent chondrogenic potential of human articular cartilage-derived chondroprogenitors in pellet culture using a novel whole pellet processing approach.}, journal = {J Orthop}, volume = {31}, year = {2022}, month = {2022 May-Jun}, pages = {45-51}, abstract = {

Purpose: Cartilage-derived chondroprogenitors have been reported to possess the biological potential for cartilage repair. However, its inherent chondrogenic potential in pellet culture needs evaluation. In-vitro cartilage regeneration models based on pellet cultures have been employed to evaluate the chondrogenic potential of stem cells. Evaluation of the degree of differentiation routinely involves paraffin embedding, sectioning, and immunohistochemical staining of the pellet. However, since chondrogenic differentiation is commonly non-uniform, processing random sections could lead to inaccurate conclusions. The study aimed at assessing the inherent lineage bias of chondroprogenitors with and without chondrogenic induction, using a novel whole pellet processing technique.

Methods: Human chondroprogenitors (n=3) were evaluated for MSC markers and processed in pellet cultures either with stromal medium (uninduced) or chondrogenic differentiation medium (induced) for 28 days. The whole pellets and the conventional paraffin-embedded sectioned pellets were subjected to Collagen type II immunostaining and assessed using confocal laser microscopy. The staining intensities of the whole pellet were compared to the paraffin sections and revalidated using qRT-PCR for COL2A1 expression.

Results: Uninduced and induced pellets displayed Collagen type II in all the layers with comparable fluorescence intensities. COL2A1 expression in both pellets was comparable to confocal results. The study demonstrated that uninduced chondroprogenitors in pellet culture possess promising inherent chondrogenic potential. Confocal imaging of whole pellets displayed different degrees of chondrogenic differentiation in the entire pellet, thus its probable in-vivo behavior.

Conclusion: The novel approach presented in this study could serve as an efficient in-vitro alternative for understanding translational application for cartilage repair.

}, issn = {0972-978X}, doi = {10.1016/j.jor.2022.03.007}, author = {Johnson, Noel Naveen and Amirtham, Soosai Manickam and Sandya Rani, B and Sathishkumar, Solomon and Rebekah, Grace and Vinod, Elizabeth} } @article {2466, title = {The CCR5 Gene Edited CD34+CD90+ Hematopoietic Stem Cell Population Serves as an Optimal Graft Source for HIV Gene Therapy}, journal = {Front. Immunol}, year = {2022}, abstract = {

Transplantation of allogenic hematopoietic stem and progenitor cells (HSPCs) with C-C chemokine receptor type 5 (CCR5) Δ32 genotype generates HIV-1 resistant immune cells. CCR5 gene edited autologous HSPCs can be a potential alternative to hematopoietic stem cell transplantation (HSCT) from HLA-matched CCR5 null donor. However, the clinical application of gene edited autologous HSPCs is critically limited by the quality of the graft, as HIV also infects the HSPCs. In this study, by using mobilized HSPCs from healthy donors, we show that the CD34+CD90+ hematopoietic stem cells (HSCs) express 7-fold lower CD4/CCR5 HIV receptors, higher levels of SAMHD1 anti-viral restriction factor, and possess lower susceptibility to HIV infection than the CD34+CD90- hematopoietic progenitor cells. Further, the treatment with small molecule cocktail of Resveratrol, UM729 and SR1(RUS) improved the in vivo engraftment potential of CD34+CD90+ HSCs. To demonstrate that CD34+CD90+ HSC population as an ideal graft for HIV gene therapy, we sort purified CD34+CD90+ HSCs, treated with RUS and then gene edited the CCR5 with single sgRNA. On transplantation, 100,000 CD34+CD90+ HSCs were sufficient for long-term repopulation of the entire bone marrow of NBSGW mice. Importantly, the gene editing efficiency of ~90\% in the infused product was maintained in vivo, facilitating the generation of CCR5 null immune cells, resistant to HIV infection. Altogether, CCR5 gene editing of CD34+CD90+ HSCs provide an ideal gene manipulation strategy for autologous HSCT based gene therapy for HIV infection.

}, doi = {https://doi.org/10.3389/fimmu.2022.792684}, author = {Karthik V. Karuppusamy and John Paul Demosthenes and Vigneshwaran Venkatesan and Abisha Crystal Christopher and Prathibha Babu and Manojkumar K. Azhagiri and Annlin Jacob and Veena Vadhini Ramalingam and Sumathi Rangaraj and Mohankumar Kumarasamypet Murugesan and Srujan Marepally and George Varghese and Alok Srivastava and Rajesh Kannangai and Saravanabhavan Thangavel} } @article {3715, title = {Efficient and error-free correction of sickle mutation in human erythroid cells using prime editor-2.}, journal = {Front Genome Ed}, volume = {4}, year = {2022}, month = {2022}, pages = {1085111}, abstract = {

Sickle cell anaemia (SCA) is one of the common autosomal recessive monogenic disorders, caused by a transverse point mutation (GAG \> GTG) at the sixth codon of the beta-globin gene, which results in haemolytic anaemia due to the fragile RBCs. Recent progress in genome editing has gained attention for the therapeutic cure for SCA. Direct correction of SCA mutation by homology-directed repair relies on a double-strand break (DSB) at the target site and carries the risk of generating beta-thalassaemic mutations if the editing is not error-free. On the other hand, base editors cannot correct the pathogenic SCA mutation resulting from A \> T base transversion. Prime editor (PE), the recently described CRISPR/Cas 9 based gene editing tool that enables precise gene manipulations without DSB and unintended nucleotide changes, is a viable approach for the treatment of SCA. However, the major limitation with the use of prime editing is the lower efficiency especially in human erythroid cell lines and primary cells. To overcome these limitations, we developed a modular lenti-viral based prime editor system and demonstrated its use for the precise modelling of SCA mutation and its subsequent correction in human erythroid cell lines. We achieved highly efficient installation of SCA mutation (up to 72\%) and its subsequent correction in human erythroid cells. For the first time, we demonstrated the functional restoration of adult haemoglobin without any unintended nucleotide changes or indel formations using the PE2 system. We also validated that the off-target effects mediated by the PE2 system is very minimal even with very efficient on-target conversion, making it a safe therapeutic option. Taken together, the modular lenti-viral prime editor system developed in this study not only expands the range of cell lines targetable by prime editor but also improves the efficiency considerably, enabling the use of prime editor for myriad molecular, genetic, and translational studies.

}, issn = {2673-3439}, doi = {10.3389/fgeed.2022.1085111}, author = {George, Anila and Ravi, Nithin Sam and Prasad, Kirti and Panigrahi, Lokesh and Koikkara, Sanya and Rajendiran, Vignesh and Devaraju, Nivedhitha and Paul, Joshua and Pai, Aswin Anand and Nakamura, Yukio and Kurita, Ryo and Balasubramanian, Poonkuzhali and Thangavel, Saravanabhavan and Marepally, Srujan and Velayudhan, Shaji R and Srivastava, Alok and Mohankumar, Kumarasamypet M} } @article {3341, title = {Erythroid lineage-specific lentiviral RNAi vectors suitable for molecular functional studies and therapeutic applications.}, journal = {Sci Rep}, volume = {12}, year = {2022}, month = {2022 08 18}, pages = {14033}, abstract = {

Numerous genes exert multifaceted roles in hematopoiesis. Therefore, we generated novel\ lineage-specific RNA interference\ (RNAi) lentiviral\ vectors, H23B-Ery-Lin-shRNA\ and H234B-Ery-Lin-shRNA, to probe the functions of these genes in erythroid cells\ without affecting other hematopoietic lineages. The lineage specificity of these vectors was confirmed by\ transducing multiple hematopoietic cells to express a fluorescent protein. Unlike the previously reported erythroid lineage RNAi vector, our vectors were designed for cloning the short hairpin RNAs (shRNAs) for\ any gene, and they also provide superior knockdown of the target gene expression with a\ single shRNA integration per cell. High-level lineage-specific downregulation of BCL11A and ZBTB7A,\ two\ well-characterized transcriptional repressors of HBG in adult erythroid cells, was achieved with substantial induction of fetal hemoglobin with a single-copy lentiviral vector integration. Transduction of primary healthy donor CD34 cells with these vectors resulted in\ \>80\% reduction in the target\ protein levels and up to 40\% elevation in the γ-chain levels in the differentiated erythroid cells. Xenotransplantation of the human CD34 cells transduced with H23B-Ery-Lin-shBCL11A\ LV in immunocompromised mice showed ~ 60\% reduction in BCL11A protein expression with ~\ 40\% elevation of γ-chain levels in the erythroid cells derived from the transduced CD34 cells. Overall, the novel erythroid lineage-specific lentiviral RNAi vectors described in this study provide a\ high-level knockdown of target gene expression in the erythroid cells, making them suitable for their use in gene therapy for hemoglobinopathies. Additionally, the design of these vectors also makes them ideal for high-throughput RNAi screening for studying normal and pathological erythropoiesis.

}, keywords = {Animals, Cell Line, Tumor, Cell Lineage, DNA-Binding Proteins, Genetic Vectors, Humans, Lentivirus, Mice, RNA Interference, RNA, Small Interfering, Transcription Factors, Transduction, Genetic}, issn = {2045-2322}, doi = {10.1038/s41598-022-13783-0}, author = {Bagchi, Abhirup and Devaraju, Nivedhitha and Chambayil, Karthik and Rajendiran, Vignesh and Venkatesan, Vigneshwaran and Sayed, Nilofer and Pai, Aswin Anand and Nath, Aneesha and David, Ernest and Nakamura, Yukio and Balasubramanian, Poonkuzhali and Srivastava, Alok and Thangavel, Saravanabhavan and Mohankumar, Kumarasamypet M and Velayudhan, Shaji R} } @article {3346, title = {Function of FMRP Domains in Regulating Distinct Roles of Neuronal Protein Synthesis.}, journal = {Mol Neurobiol}, volume = {59}, year = {2022}, month = {2022 Dec}, pages = {7370-7392}, abstract = {

The Fragile-X Mental Retardation Protein (FMRP) is an RNA binding protein that regulates translation of mRNAs essential for synaptic development and plasticity. FMRP interacts with a specific set of mRNAs, aids in their microtubule-dependent transport and regulates their translation through its association with ribosomes. However, the biochemical role of FMRP{\textquoteright}s domains in forming neuronal granules and associating with microtubules and ribosomes is currently undefined. We report that the C-terminus domain of FMRP is sufficient to bind to ribosomes akin to the full-length protein. Furthermore, the C-terminus domain alone is essential and responsible for FMRP-mediated neuronal translation repression. However, dendritic distribution of FMRP and its microtubule association is favored by the synergistic combination of FMRP domains rather than individual domains. Interestingly, we show that the phosphorylation of hFMRP at Serine-500 is important in modulating the dynamics of translation by controlling ribosome association. This is a fundamental mechanism governing the size and number of FMRP puncta that contain actively translating ribosomes. Finally through the use of pathogenic mutations, we emphasize the hierarchical contribution of FMRP{\textquoteright}s domains in translation regulation.

}, keywords = {Fragile X Mental Retardation Protein, Fragile X Syndrome, Humans, Microtubules, Neurons, Protein Biosynthesis, Ribosomes, RNA, Messenger}, issn = {1559-1182}, doi = {10.1007/s12035-022-03049-1}, author = {D{\textquoteright}Souza, Michelle Ninochka and Ramakrishna, Sarayu and Radhakrishna, Bindushree K and Jhaveri, Vishwaja and Ravindran, Sreenath and Yeramala, Lahari and Nair, Deepak and Palakodeti, Dasaradhi and Muddashetty, Ravi S} } @article {2545, title = {Genome Engineering of Hematopoietic Stem Cells Using CRISPR/Cas9 System.}, journal = {Methods Mol Biol}, volume = {2429}, year = {2022}, month = {2022}, pages = {307-331}, abstract = {

Ex vivo genetic manipulation of autologous hematopoietic stem and progenitor cells (HSPCs) is a viable strategy for the treatment of hematologic and primary immune disorders. Targeted genome editing of HSPCs using the CRISPR-Cas9 system provides an effective platform to edit the desired genomic locus for therapeutic purposes with minimal off-target effects. In this chapter, we describe the detailed methodology for the CRISPR-Cas9 mediated gene knockout, deletion, addition, and correction in human HSPCs by viral and nonviral approaches. We also present a comprehensive protocol for the analysis of genome modified HSPCs toward the erythroid and megakaryocyte lineage in vitro and the long-term multilineage reconstitution capacity in the recently developed NBSGW mouse model that supports human erythropoiesis.

}, keywords = {Animals, CRISPR-Cas Systems, Gene Editing, Hematopoietic Stem Cell Transplantation, Hematopoietic Stem Cells, Mice, Transplantation, Autologous}, issn = {1940-6029}, doi = {10.1007/978-1-0716-1979-7_20}, author = {Devaraju, Nivedhitha and Rajendiran, Vignesh and Ravi, Nithin Sam and Mohankumar, Kumarasamypet M} } @article {2465, title = {Identification of novel HPFH-like mutations by CRISPR base editing that elevate the expression of fetal hemoglobin.}, journal = {Elife}, volume = {11}, year = {2022}, month = {2022 02 11}, abstract = {

Naturally occurring point mutations in the promoter switch hemoglobin synthesis from defective adult beta-globin to fetal gamma-globin in sickle cell patients with hereditary persistence of fetal hemoglobin (HPFH) and ameliorate the clinical severity. Inspired by this natural phenomenon, we tiled the highly homologous proximal promoters using adenine and cytosine base editors that avoid the generation of large deletions and identified novel regulatory regions including a cluster at the -123 region. Base editing at -123 and -124 bp of promoter induced fetal hemoglobin (HbF) to a higher level than disruption of well-known BCL11A binding site in erythroblasts derived from human CD34+ hematopoietic stem and progenitor cells (HSPC). We further demonstrated in vitro that the introduction of -123T \> C and -124T \> C HPFH-like mutations drives gamma-globin expression by creating a de novo binding site for KLF1. Overall, our findings shed light on so far unknown regulatory elements within the promoter and identified additional targets for therapeutic upregulation of fetal hemoglobin.

}, keywords = {Adenine, Anemia, Sickle Cell, beta-Globins, beta-Thalassemia, Cell Line, Clustered Regularly Interspaced Short Palindromic Repeats, CRISPR-Cas Systems, Cytosine, Fetal Hemoglobin, gamma-Globins, Gene Editing, Hematopoietic Stem Cells, Humans, Point Mutation, Promoter Regions, Genetic}, issn = {2050-084X}, doi = {10.7554/eLife.65421}, author = {Ravi, Nithin Sam and Wienert, Beeke and Wyman, Stacia K and Bell, Henry William and George, Anila and Mahalingam, Gokulnath and Vu, Jonathan T and Prasad, Kirti and Bandlamudi, Bhanu Prasad and Devaraju, Nivedhitha and Rajendiran, Vignesh and Syedbasha, Nazar and Pai, Aswin Anand and Nakamura, Yukio and Kurita, Ryo and Narayanasamy, Muthuraman and Balasubramanian, Poonkuzhali and Thangavel, Saravanabhavan and Marepally, Srujan and Velayudhan, Shaji R and Srivastava, Alok and DeWitt, Mark A and Crossley, Merlin and Corn, Jacob E and Mohankumar, Kumarasamypet M} } @article {2400, title = {Inflammation-specific targeted carriers for local drug delivery to inflammatory bowel disease.}, journal = {Biomaterials}, volume = {281}, year = {2022}, month = {2022 Jan 05}, pages = {121364}, abstract = {

Delivering drugs directly to the inflamed intestinal sites to treat inflammatory bowel disease (IBD), particularly Crohn{\textquoteright}s and ulcerative colitis, is highly challenging. Recent advances in colitis therapy medications are expanding opportunities for improving local on-site drug availability by minimising the associated systemic side-effects. Drug delivery with targeted carrier systems has shown the potential to increase site-specificity, stability, and therapeutic efficacy. Herein, we report the development of a strong anionic charged inflammation targeted nanocarriers (IT-NCs) loaded with an immunosuppressant model drug. This system showed preferential adhesion on a charge-modified surface in vitro, and in both dextran sulfate sodium (DSS) and TNBS colitis mice in vivo models. IT-NCs showed improved colitis phenotype therapeutic efficacy in both animal models compared to free drug. Furthermore, ex vivo study of colon tissue biopsies from patients with colitis revealed that IT-NCs adhered preferentially to inflamed biopsies compared to normal. Together, our results suggest that IT-NCs have promising therapeutic potential as delivery carriers{\textquoteright} in colitis management.

}, issn = {1878-5905}, doi = {10.1016/j.biomaterials.2022.121364}, author = {Kotla, Niranjan G and Singh, Rajbir and Baby, Becca V and Rasala, Swetha and Rasool, Jawad and Hynes, Sean O and Martin, Darrell and Egan, Laurence J and Vemula, Praveen K and Jala, Venkatakrishna R and Rochev, Yury and Pandit, Abhay} } @article {2502, title = {Influence of Hydrophobicity in the Hydrophilic Region of Cationic Lipids on Enhancing Nucleic Acid Delivery and Gene Editing.}, journal = {ACS Appl Bio Mater}, volume = {5}, year = {2022}, month = {2022 Apr 18}, pages = {1489-1500}, abstract = {

Intracellular delivery of biomolecules using non-viral vectors critically depends on the vectors{\textquoteright} ability to allow the escape and release of the contents from the endosomes. Prior findings demonstrated that aromatic/hydrophobic group-containing amino acids such as phenylalanine (F) and tryptophan (W) destabilize cellular membranes by forming pores in the lipid bilayer. Taking cues from these findings, we have developed four α-tocopherol-based cationic amphiphiles by varying the aromatic/hydrophobic amino acids such as glycine (G), proline (P), phenylalanine (F), and tryptophan (W) as head groups and triazole in the linker region to study their impact on endosomal escape for the enhanced transfection efficacy. The lipids tocopherol-triazole-phenylalanine (TTF) and tocopherol-triazole-tryptophan (TTW) exhibited similar potential to commercial transfecting reagents, Lipofectamine (LF) 3000 and Lipofectamine Messenger Max (LFMM), respectively, in transfecting plasmid DNA and messenger RNA in multiple cultured cell lines. The TTW liposome was also found to be effective in delivering Cas9 mRNA and demonstrated equal efficiency of gene editing AAVS1 locus compared to LFMM in CHO, Neuro-2a, and EA.HY926 cell lines. In this current investigation, it is shown that the synthesized cationic lipids with aromatic hydrophobic R group-containing amino acids are safe, economic, and actually more efficient in nucleic acid delivery and genome-editing applications. These findings can be further explored in the genome-editing approach for treating genetic disorders.

}, keywords = {alpha-Tocopherol, Amino Acids, Cations, Gene Editing, Gene Transfer Techniques, Hydrophobic and Hydrophilic Interactions, Lipids, Nucleic Acids, Phenylalanine, Triazoles, Tryptophan}, issn = {2576-6422}, doi = {10.1021/acsabm.1c01226}, author = {Rapaka, Hithavani and Manturthi, Shireesha and Arjunan, Porkizhi and Venkatesan, Vigneshwaran and Thangavel, Saravanabhavan and Marepally, Srujan and Patri, Srilakshmi V} } @article {3343, title = {Initiation of wound healing is regulated by the convergence of mechanical and epigenetic cues.}, journal = {PLoS Biol}, volume = {20}, year = {2022}, month = {2022 09}, pages = {e3001777}, abstract = {

Wound healing in the skin is a complex physiological process that is a product of a cell state transition from homeostasis to repair. Mechanical cues are increasingly being recognized as important regulators of cellular reprogramming, but the mechanism by which it is translated to changes in gene expression and ultimately cellular behavior remains largely a mystery. To probe the molecular underpinnings of this phenomenon further, we used the down-regulation of caspase-8 as a biomarker of a cell entering the wound healing program. We found that the wound-induced release of tension within the epidermis leads to the alteration of gene expression via the nuclear translocation of the DNA methyltransferase 3A (DNMT3a). This enzyme then methylates promoters of genes that are known to be down-regulated in response to wound stimuli as well as potentially novel players in the repair program. Overall, these findings illuminate the convergence of mechanical and epigenetic signaling modules that are important regulators of the transcriptome landscape required to initiate the tissue repair process in the differentiated layers of the epidermis.

}, keywords = {Biomarkers, Caspase 8, Cues, Epigenesis, Genetic, Wound Healing}, issn = {1545-7885}, doi = {10.1371/journal.pbio.3001777}, author = {Bhatt, Tanay and Dey, Rakesh and Hegde, Akshay and Ketkar, Alhad Ashok and Pulianmackal, Ajai J and Deb, Ashim P and Rampalli, Shravanti and Jamora, Colin} } @article {3642, title = {Intermittent scavenging of storage lesion from stored red blood cells by electrospun nanofibrous sheets enhances their quality and shelf-life.}, journal = {Nat Commun}, volume = {13}, year = {2022}, month = {2022 Dec 01}, pages = {7394}, abstract = {

Transfusion of healthy red blood cells (RBCs) is a lifesaving process. However, upon storing RBCs, a wide range of damage-associate molecular patterns (DAMPs), such as cell-free DNA, nucleosomes, free-hemoglobin, and poly-unsaturated-fatty-acids are generated. DAMPs can further damage RBCs; thus, the quality of stored RBCs declines during the storage and limits their shelf-life. Since these DAMPs consist of either positive or negative charged species, we developed taurine and acridine containing electrospun-nanofibrous-sheets (Tau-AcrNFS), featuring anionic, cationic charges and an DNA intercalating group on their surfaces. We show that Tau-AcrNFS are efficient in scavenging DAMPs from stored human and mice RBCs ex vivo. We find that intermittent scavenging of DAMPs by Tau-AcrNFS during the storage reduces the loss of RBC membrane integrity and reduces discocytes-to-spheroechinocytes transformation in stored-old-RBCs. We perform RBC-transfusion studies in mice to reveal that intermittent removal of DAMPs enhances the quality of stored-old-RBCs equivalent to freshly collected RBCs, and increases their shelf-life by ~22\%. Such prophylactic technology may lead to the development of novel blood bags or medical device, and may therefore impact healthcare by reducing transfusion-related adverse effects.

}, keywords = {Acridines, Animals, Drug-Related Side Effects and Adverse Reactions, Erythrocytes, Humans, Mice, Nanofibers, Research Personnel}, issn = {2041-1723}, doi = {10.1038/s41467-022-35269-3}, author = {Pandey, Subhashini and Mahato, Manohar and Srinath, Preethem and Bhutani, Utkarsh and Goap, Tanu Jain and Ravipati, Priusha and Vemula, Praveen Kumar} } @article {3339, title = {NMDAR mediated dynamic changes in mA inversely correlates with neuronal translation.}, journal = {Sci Rep}, volume = {12}, year = {2022}, month = {2022 07 05}, pages = {11317}, abstract = {

Epitranscriptome modifications are crucial in translation regulation and essential for maintaining cellular homeostasis. N6 methyladenosine (mA) is one of the most abundant and well-conserved epitranscriptome modifications, which is known to play a pivotal role in diverse aspects of neuronal functions. However, the role of mA modifications with respect to activity-mediated translation regulation and synaptic plasticity has not been studied. Here, we investigated the role of mA modification in response to NMDAR stimulation. We have consistently observed that 5\ min NMDAR stimulation causes an increase in eEF2 phosphorylation. Correspondingly, NMDAR stimulation caused a significant increase in the mA signal at 5\ min time point, correlating with the global translation inhibition. The NMDAR induced increase in the mA signal is accompanied by the redistribution of the mA marked RNAs from translating to the non-translating pool of ribosomes. The increased mA levels are well correlated with the reduced FTO levels observed on NMDAR stimulation. Additionally, we show that inhibition of FTO prevents NMDAR mediated changes in mA levels. Overall, our results establish RNA-based molecular readout which corelates with the NMDAR-dependent translation regulation which helps in understanding changes in protein synthesis.

}, keywords = {Adenosine, Neurons, Phosphorylation, Receptors, N-Methyl-D-Aspartate, RNA}, issn = {2045-2322}, doi = {10.1038/s41598-022-14798-3}, author = {Gowda, Naveen Kumar Chandappa and Nawalpuri, Bharti and Ramakrishna, Sarayu and Jhaveri, Vishwaja and Muddashetty, Ravi S} } @article {2422, title = {Novel Mutations in β- Gene in Indian Patients With Dilated Cardiomyopathy.}, journal = {CJC Open}, volume = {4}, year = {2022}, month = {2022 Jan}, pages = {1-11}, abstract = {

Background: Heart failure is a hallmark of severe hypertrophic cardiomyopathy and dilated cardiomyopathy (DCM). Several mutations in the gene lead to hypertrophic cardiomyopathy. Recently, causative mutations in the gene have also been detected in DCM from different populations.

Methods: Here, we sequenced the gene in 137 Indian DCM patients and 167 ethnically matched healthy controls to detect the frequency of mutations and their association.

Results: Our study revealed 27 variations, of which 7 mutations (8.0\%) were detected exclusively in Indian DCM patients for the first time. These included 4 missense mutations-Arg723His, Phe510Leu, His358Leu, and Ser384Tyr (2.9\%); a frameshift mutation-Asn676_T-del (1.5\%); and 2 splice-site mutations (IVS17+2T) T\>G and (IVS19-1G) G\>A (3.6\%). Remarkably, all 4 missense mutations altered evolutionarily conserved amino acids. All 4 missense mutations were predicted to be pathogenic by 2 bioinformatics tools-polymorphism phenotyping v2 (PolyPhen-2) and sorting intolerant from tolerant (SIFT). In addition, the 4 homology models of β-MYH7-p.Leu358, p.Tyr384, p.Leu510, and p.His723-displayed root-mean-square deviations of \~{}2.55 {\r A}, \~{}1.24 {\r A}, \~{}3.36 {\r A}, and \~{}3.86 {\r A}, respectively.

Conclusions: In the present study, we detected numerous novel, unique, and rare mutations in the gene exclusively in Indian DCM patients (8.0\%). Here, we demonstrated how each mutant (missense) uniquely disrupts a critical network of non-bonding interactions at the mutation site (molecular level) and may contribute to development of dilated cardiomyopathy (DCM). Therefore, our findings may provide insight into the understanding of the molecular bases of disease and into diagnosis along with promoting novel therapeutic strategies (through personalized medicine).

}, issn = {2589-790X}, doi = {10.1016/j.cjco.2021.07.020}, author = {Rani, Deepa Selvi and Vijaya Kumar, Archana and Nallari, Pratibha and Sampathkumar, Katakam and Dhandapany, Perundurai S and Narasimhan, Calambur and Rathinavel, Andiappan and Thangaraj, Kumarasamy} } @article {2884, title = {Preferential Expansion of Human CD34CD133CD90 Hematopoietic Stem Cells Enhances Gene-Modified Cell Frequency for Gene Therapy.}, journal = {Hum Gene Ther}, volume = {33}, year = {2022}, month = {2022 02}, pages = {188-201}, abstract = {

CD34CD133CD90 hematopoietic stem cells (HSCs) are responsible for long-term multilineage hematopoiesis, and the high frequency of gene-modified HSCs is crucial for the success of hematopoietic stem and progenitor cell (HSPC) gene therapy. However, the culture and gene manipulation steps of HSPC graft preparation significantly reduce the frequency of HSCs, thus necessitating large doses of HSPCs and reagents for the manipulation. In this study, we identified a combination of small molecules, Resveratrol, UM729, and SR1 that preferentially expands CD34CD133CD90 HSCs over other subpopulations of adult HSPCs in culture. The preferential expansion enriches the HSCs in culture, enhances the adhesion, and results in a sixfold increase in the long-term engraftment in NSG mice. Further, the culture-enriched HSCs are more responsive to gene modification by lentiviral transduction and gene editing, increasing the frequency of gene-modified HSCs up to 10-fold . The yield of gene-modified HSCs obtained by the culture enrichment is similar to the sort-purification of HSCs and superior to Cyclosporin-H treatment. Our study addresses a critical challenge of low frequency of gene modified HSCs in HSPC graft by developing and demonstrating a facile HSPC culture condition that increases the frequency of gene-modified cells . This strategy will improve the outcome of HSPC gene therapy and also simplify the gene manipulation process.

}, keywords = {Animals, Antigens, CD34, Fetal Blood, Genetic Therapy, Hematopoietic Stem Cell Transplantation, Hematopoietic Stem Cells, Humans, Mice, Mice, Inbred NOD, Mice, SCID}, issn = {1557-7422}, doi = {10.1089/hum.2021.089}, author = {Christopher, Abisha Crystal and Venkatesan, Vigneshwaran and Karuppusamy, Karthik V and Srinivasan, Saranya and Babu, Prathibha and Azhagiri, Manoj Kumar K and Chambayil, Karthik and Bagchi, Abhirup and Rajendiran, Vignesh and Ravi, Nithin Sam and Kumar, Sanjay and Marepally, Srujan Kumar and Mohankumar, Kumarasamypet Murugesan and Srivastava, Alok and Velayudhan, Shaji R and Thangavel, Saravanabhavan} } @article {3645, title = {Single step fabrication of hollow microneedles and an experimental package for controlled drug delivery.}, journal = {Int J Pharm}, volume = {632}, year = {2022}, month = {2022 Dec 24}, pages = {122546}, abstract = {

Hollow microneedle arrays (HMNs) are an excellent choice for managing chronic diseases requiring the administration of multiple drug doses over a prolonged duration. However, HMNs have gained partial success due to limitations in their manufacturing capabilities, and cumbersome processes. In the present study, polymeric HMNs were fabricated using a novel single-step drop-casting process without needing cleanroom facilities, and sophisticated instrumentation. When drop casted on the pyramidal tip stainless steel needles, the optimized polymer solution allowed the reproducible formation of desired height HMMs on a detachable acrylic base. To enable broader applications, the base with HMNs was integrated into an experimental package built to deliver a dose of\ \~{}\ 5\ {\textmu}L per 30{\textdegree} clockwise rotation of the actuator, allowing multiple metered drug dose administrations. The fabricated HMNs were optically imaged, and tested for mechanical integrity and stability. The working and functional utility of the HMNs package in delivering metered drug doses was demonstrated by delivering vitamin B12 (ex vivo) and insulin (in vivo), respectively. The optimized process can be used for the large-scale manufacturing of HMNs and the experimental package shows the potential to be further developed into a wearable device.

}, issn = {1873-3476}, doi = {10.1016/j.ijpharm.2022.122546}, author = {Ghate, Vivek and Renjith, Anu and Badnikar, Kedar and Pahal, Suman and Jayadevi, Shreyas N and Nayak, Manjunatha M and Vemula, Praveen K and Subramanyam, Dinesh N} } @article {2474, title = {Skin-Permeable Nano-Lithocholic Lipidoid Efficiently Alleviates Psoriasis-like Chronic Skin Inflammations.}, journal = {ACS Appl Mater Interfaces}, year = {2022}, month = {2022 Mar 29}, abstract = {

Long-term application of topical therapeutics for psoriasis has a plethora of side effects. Additionally, skin-permeating agents used in their formulations for deeper dermal delivery damage the skin. To address these limitations, we developed novel lithocholic acid analogues that could form lipid nanoparticles (nano-LCs) spontaneously in the aqueous milieu, permeate through the skin, penetrate the deeper dermal layers, and exert anti-inflammatory effects against psoriasis-like chronic skin inflammations. Prior findings demonstrated that lithocholic acid acts as a vitamin D receptor agonist without affecting the Ca metabolism and also as an antagonist for ephrin type-A receptor 2 (EphA2). Taking cues from the previous findings, lithocholic acid derivatives with twin alkyl chains (LC6, LC8, LC10, and LC-12) were synthesized, nanoparticles (nano-LCs) were prepared, and they were evaluated for their skin permeability and anti-inflammatory properties. Among these nano-LCs, nano-LC10 demonstrated superior anti-inflammatory properties and inhibition of keratinocyte proliferation in various cell-based evaluations. Furthermore, the therapeutic efficiency of nano-LC10 was evaluated in an imiquimod-induced psoriasis-like mouse model and demonstrated comparable efficiency with the standard topical formulation, Sorvate, in reducing skin inflammations. Nano-LC10 also reduced systemic inflammation, organ toxicity, and also proinflammatory serum cytokine levels. Overall, nano-lithocholic lipidoid (nano-LC10) can be a potential novel class of therapeutics for topical application in treating psoriasis.

}, issn = {1944-8252}, doi = {10.1021/acsami.1c19180}, author = {Rachamalla, Hari Krishnareddy and Voshavar, Chandrashekhar and Arjunan, Porkizhi and Mahalingam, Gokulnath and Chowath, Rashmi Praksash and Banerjee, Rajkumar and Vemula, Praveen Kumar and Marepally, Srujan} } @article {2882, title = {Supplementation of articular cartilage-derived chondroprogenitors with bone morphogenic protein-9 enhances chondrogenesis without affecting hypertrophy.}, journal = {Biotechnol Lett}, year = {2022}, month = {2022 Aug 03}, abstract = {

INTRODUCTION: Chondroprogenitors (CPCs) have emerged as a promising cellular therapy for cartilage-related pathologies due to their inherent primed chondrogenic potential. Studies report that the addition of growth factors such as parathyroid hormone (PTH) and Bone Morphogenic Protein (BMP) enhance the chondroinducive potential in chondrocytes and mesenchymal stem cells. This study evaluated if supplementation of the standard culture medium for cell expansion with 1-34 PTH and BMP-9 would enhance the chondrogenic potential of CPCs and reduce their hypertrophic tendency.

METHODS: Human chondrocytes were isolated from patients undergoing total knee replacement for osteoarthritis (n = 3). Following fibronectin adhesion assay, passage 1 CPCs were divided and further expanded under three culture conditions (a) control, i.e., cells continued under standard culture conditions, (b) 1-34 PTH group, additional intermittent 6\ h exposure with 1-34 PTH and (c) BMP-9 group, additional BMP-9 during culture expansion. All the groups were evaluated for population-doubling, cell cycle analysis, surface marker and gene expression for chondrogenesis, hypertrophy, multilineage differentiation and GAG (glycosaminoglycan)/DNA following chondrogenic differentiation.

RESULTS: Concerning growth kinetics, the BMP-9 group exhibited a significantly lower S-phase and population-doubling when compared to the other two groups. Qualitative analysis for chondrogenic potential (Alcian blue, Safranin O staining and Toluidine blue for GAG) revealed that the BMP-9 group exhibited the highest uptake. The BMP-9 group also showed significantly higher COL2A1 expression than the control group, with no change in the hypertrophy marker expression.

CONCLUSION: BMP-9 can potentially be used as an additive for CPCs expansion, to enhance their chondrogenic potential without affecting their low hypertrophic tendency. The mitigating effects of 1-34PTH on hypertrophy would benefit further investigation when used in combination with BMP-9 to enhance chondrogenesis whilst reducing hypertrophy.

}, issn = {1573-6776}, doi = {10.1007/s10529-022-03280-9}, author = {Padmaja, Kawin and Amirtham, Soosai Manickam and Rebekah, Grace and Sathishkumar, Solomon and Vinod, Elizabeth} } @article {2463, title = {Whole genome sequencing delineates regulatory, copy number, and cryptic splice variants in early onset cardiomyopathy.}, journal = {NPJ Genom Med}, volume = {7}, year = {2022}, month = {2022 Mar 14}, pages = {18}, abstract = {

Cardiomyopathy (CMP) is a heritable disorder. Over 50\% of cases are gene-elusive on clinical gene panel testing. The contribution of variants in non-coding DNA elements that result in cryptic splicing and regulate gene expression has not been explored. We analyzed whole-genome sequencing (WGS) data in a discovery cohort of 209 pediatric CMP patients and 1953 independent replication genomes and exomes. We searched for protein-coding variants, and non-coding variants predicted to affect the function or expression of genes. Thirty-nine percent of cases harbored pathogenic coding variants in known CMP genes, and 5\% harbored high-risk loss-of-function (LoF) variants in additional candidate CMP genes. Fifteen percent harbored high-risk regulatory variants in promoters and enhancers of CMP genes (odds ratio 2.25, p = 6.70 {\texttimes} 10 versus controls). Genes involved in α-dystroglycan glycosylation (FKTN, DTNA) and desmosomal signaling (DSC2, DSG2) were most highly enriched for regulatory variants (odds ratio 6.7-58.1). Functional effects were confirmed in patient myocardium and reporter assays in human cardiomyocytes, and in zebrafish CRISPR knockouts. We provide strong evidence for the genomic contribution of functionally active variants in new genes and in regulatory elements of known CMP genes to early onset CMP.

}, issn = {2056-7944}, doi = {10.1038/s41525-022-00288-y}, author = {Lesurf, Robert and Said, Abdelrahman and Akinrinade, Oyediran and Breckpot, Jeroen and Delfosse, Kathleen and Liu, Ting and Yao, Roderick and Persad, Gabrielle and McKenna, Fintan and Noche, Ramil R and Oliveros, Winona and Mattioli, Kaia and Shah, Shreya and Miron, Anastasia and Yang, Qian and Meng, Guoliang and Yue, Michelle Chan Seng and Sung, Wilson W L and Thiruvahindrapuram, Bhooma and Lougheed, Jane and Oechslin, Erwin and Mondal, Tapas and Bergin, Lynn and Smythe, John and Jayappa, Shashank and Rao, Vinay J and Shenthar, Jayaprakash and Dhandapany, Perundurai S and Semsarian, Christopher and Weintraub, Robert G and Bagnall, Richard D and Ingles, Jodie and Mel{\'e}, Marta and Maass, Philipp G and Ellis, James and Scherer, Stephen W and Mital, Seema} } @article {2211, title = {Adiponectin receptor 1 variants contribute to hypertrophic cardiomyopathy that can be reversed by rapamycin.}, journal = {Sci Adv}, volume = {7}, year = {2021}, month = {2021 Jan}, abstract = {

Hypertrophic cardiomyopathy (HCM) is a heterogeneous genetic heart muscle disease characterized by hypertrophy with preserved or increased ejection fraction in the absence of secondary causes. However, recent studies have demonstrated that a substantial proportion of individuals with HCM also have comorbid diabetes mellitus (~10\%). Whether genetic variants may contribute a combined phenotype of HCM and diabetes mellitus is not known. Here, using next-generation sequencing methods, we identified novel and ultrarare variants in adiponectin receptor 1 () as risk factors for HCM. Biochemical studies showed that variants dysregulate glucose and lipid metabolism and cause cardiac hypertrophy through the p38/mammalian target of rapamycin and/or extracellular signal-regulated kinase pathways. A transgenic mouse model expressing an variant displayed cardiomyopathy that recapitulated the cellular findings, and these features were rescued by rapamycin. Our results provide the first evidence that variants can cause HCM and provide new insights into regulation.

}, issn = {2375-2548}, doi = {10.1126/sciadv.abb3991}, author = {Dhandapany, Perundurai S and Kang, Soojeong and Kashyap, Deepak K and Rajagopal, Raksha and Sundaresan, Nagalingam R and Singh, Rajvir and Thangaraj, Kumarasamy and Jayaprakash, Shilpa and Manjunath, Cholenahally N and Shenthar, Jayaprakash and Lebeche, Djamel} } @article {2328, title = {APOE4 Affects Basal and NMDAR-Mediated Protein Synthesis in Neurons by Perturbing Calcium Homeostasis.}, journal = {J Neurosci}, volume = {41}, year = {2021}, month = {2021 Oct 20}, pages = {8686-8709}, abstract = {

Apolipoprotein E (APOE), one of the primary lipoproteins in the brain has three isoforms in humans, APOE2, APOE3, and APOE4. APOE4 is the most well-established risk factor increasing the predisposition for Alzheimer{\textquoteright}s disease (AD). The presence of the APOE4 allele alone is shown to cause synaptic defects in neurons and recent studies have identified multiple pathways directly influenced by APOE4. However, the mechanisms underlying APOE4-induced synaptic dysfunction remain elusive. Here, we report that the acute exposure of primary cortical neurons or synaptoneurosomes to APOE4 leads to a significant decrease in global protein synthesis. Primary cortical neurons were derived from male and female embryos of Sprague Dawley (SD) rats or C57BL/6J mice. Synaptoneurosomes were prepared from P30 male SD rats. APOE4 treatment also abrogates the NMDA-mediated translation response indicating an alteration of synaptic signaling. Importantly, we demonstrate that both APOE3 and APOE4 generate a distinct translation response which is closely linked to their respective calcium signature. Acute exposure of neurons to APOE3 causes a short burst of calcium through NMDA receptors (NMDARs) leading to an initial decrease in protein synthesis which quickly recovers. Contrarily, APOE4 leads to a sustained increase in calcium levels by activating both NMDARs and L-type voltage-gated calcium channels (L-VGCCs), thereby causing sustained translation inhibition through eukaryotic translation elongation factor 2 (eEF2) phosphorylation, which in turn disrupts the NMDAR response. Thus, we show that APOE4 affects basal and activity-mediated protein synthesis responses in neurons by affecting calcium homeostasis. Defective protein synthesis has been shown as an early defect in familial Alzheimer{\textquoteright}s disease (AD). However, this has not been studied in the context of sporadic AD, which constitutes the majority of cases. In our study, we show that Apolipoprotein E4 (APOE4), the predominant risk factor for AD, inhibits global protein synthesis in neurons. APOE4 also affects NMDA activity-mediated protein synthesis response, thus inhibiting synaptic translation. We also show that the defective protein synthesis mediated by APOE4 is closely linked to the perturbation of calcium homeostasis caused by APOE4 in neurons. Thus, we propose the dysregulation of protein synthesis as one of the possible molecular mechanisms to explain APOE4-mediated synaptic and cognitive defects. Hence, the study not only suggests an explanation for the APOE4-mediated predisposition to AD, it also bridges the gap in understanding APOE4-mediated pathology.

}, issn = {1529-2401}, doi = {10.1523/JNEUROSCI.0435-21.2021}, author = {Ramakrishna, Sarayu and Jhaveri, Vishwaja and Konings, Sabine C and Nawalpuri, Bharti and Chakraborty, Sumita and Holst, Bj{\o}rn and Schmid, Benjamin and Gouras, Gunnar K and Freude, Kristine K and Muddashetty, Ravi S} } @article {2362, title = {Astrocytic reactivity triggered by defective autophagy and metabolic failure causes neurotoxicity in frontotemporal dementia type 3.}, journal = {Stem Cell Reports}, volume = {16}, year = {2021}, month = {2021 Nov 09}, pages = {2736-2751}, abstract = {

Frontotemporal dementia type 3 (FTD3), caused by a point mutation in the charged multivesicular body protein 2B (CHMP2B), affects mitochondrial ultrastructure and the endolysosomal pathway in neurons. To dissect the astrocyte-specific impact of mutant CHMP2B expression, we generated astrocytes from human induced pluripotent stem cells (hiPSCs) and confirmed our findings in CHMP2B mutant mice. Our data provide mechanistic insights into how defective autophagy causes perturbed mitochondrial dynamics with impaired glycolysis, increased reactive oxygen species, and elongated mitochondrial morphology, indicating increased mitochondrial fusion in FTD3 astrocytes. This shift in astrocyte homeostasis triggers a reactive astrocyte phenotype and increased release of toxic cytokines, which accumulate in nuclear factor kappa b (NF-κB) pathway activation with increased production of CHF, LCN2, and C3 causing neurodegeneration.

}, issn = {2213-6711}, doi = {10.1016/j.stemcr.2021.09.013}, author = {Chandrasekaran, Abinaya and Dittlau, Katarina Stoklund and Corsi, Giulia I and Haukedal, Henriette and Doncheva, Nadezhda T and Ramakrishna, Sarayu and Ambardar, Sheetal and Salcedo, Claudia and Schmidt, Sissel I and Zhang, Yu and Cirera, Susanna and Pihl, Maria and Schmid, Benjamin and Nielsen, Troels Tolstrup and Nielsen, J{\o}rgen E and Kolko, Miriam and Kobol{\'a}k, Julianna and Dinny{\'e}s, Andr{\'a}s and Hyttel, Poul and Palakodeti, Dasaradhi and Gorodkin, Jan and Muddashetty, Ravi S and Meyer, Morten and Aldana, Blanca I and Freude, Kristine K} } @article {2375, title = {Biophysical properties of the isolated spike protein binding helix of human ACE2.}, journal = {Biophys J}, volume = {120}, year = {2021}, month = {2021 07 20}, pages = {2785-2792}, abstract = {

The entry of the severe acute respiratory syndrome coronavirus 2 virus in human cells is mediated by the binding of its surface spike protein to the human angiotensin-converting enzyme 2 (ACE2) receptor. A 23-residue long helical segment (SBP1) at the binding interface of human ACE2 interacts with viral spike protein and therefore has generated considerable interest as a recognition element for virus detection. Unfortunately, emerging reports indicate that the affinity of SBP1 to the receptor-binding domain of the spike protein is much lower than that of the ACE2 receptor itself. Here, we examine the biophysical properties of SBP1 to reveal factors leading to its low affinity for the spike protein. Whereas SBP1 shows good solubility (solubility \> 0.8\ mM), circular dichroism spectroscopy shows that it is mostly disordered with some antiparallel β-sheet content and no helicity. The helicity is substantial (\>20\%) only upon adding high concentrations (>=20\% v/v) of 2,2,2-trifluoroethanol, a helix promoter. Fluorescence correlation spectroscopy and single-molecule photobleaching studies show that the peptide oligomerizes at concentrations \>50\ nM. We hypothesized that mutating the hydrophobic residues (F28, F32, and F40) of SBP1, which do not directly interact with the spike protein, to alanine would reduce peptide oligomerization without affecting its spike binding affinity. Whereas the mutant peptide (SBP1) shows substantially reduced oligomerization propensity, it does not show improved helicity. Our study shows that the failure of efforts, so far, to produce a short SBP1 mimic with a high affinity for the spike protein is not only due to the lack of helicity but is also due to the heretofore unrecognized problem of oligomerization.

}, keywords = {Angiotensin-Converting Enzyme 2, COVID-19, Humans, Peptidyl-Dipeptidase A, Protein Binding, SARS-CoV-2, Spike Glycoprotein, Coronavirus}, issn = {1542-0086}, doi = {10.1016/j.bpj.2021.06.017}, author = {Das, Anirban and Vishvakarma, Vicky and Dey, Arpan and Dey, Simli and Gupta, Ankur and Das, Mitradip and Vishwakarma, Krishna Kant and Roy, Debsankar Saha and Yadav, Swati and Kesarwani, Shubham and Venkatramani, Ravindra and Maiti, Sudipta} } @article {2326, title = {Correction of amygdalar dysfunction in a rat model of fragile X syndrome.}, journal = {Cell Rep}, volume = {37}, year = {2021}, month = {2021 Oct 12}, pages = {109805}, abstract = {

Fragile X syndrome (FXS), a commonly inherited form of autism and intellectual disability, is associated with emotional symptoms that implicate dysfunction of the amygdala. However, current understanding of the pathogenesis of the disease is based primarily on studies in the hippocampus and neocortex, where FXS defects have been corrected by inhibiting group I metabotropic glutamate receptors (mGluRs). Here, we observe that activation, rather than inhibition, of mGluRs in the basolateral amygdala reverses impairments in a rat model of FXS. FXS rats exhibit deficient recall of auditory conditioned fear, which is accompanied by a range of in\ vitro and in\ vivo deficits in synaptic transmission and plasticity. We find presynaptic mGluR5 in the amygdala, activation of which reverses deficient synaptic transmission and plasticity, thereby restoring normal fear learning in FXS rats. This highlights the importance of modifying the prevailing mGluR-based framework for therapeutic strategies to include circuit-specific differences in FXS pathophysiology.

}, issn = {2211-1247}, doi = {10.1016/j.celrep.2021.109805}, author = {Fernandes, Giselle and Mishra, Pradeep K and Nawaz, Mohammad Sarfaraz and Donlin-Asp, Paul G and Rahman, Mohammed Mostafizur and Hazra, Anupam and Kedia, Sonal and Kayenaat, Aiman and Songara, Dheeraj and Wyllie, David J A and Schuman, Erin M and Kind, Peter C and Chattarji, Sumantra} } @article {2292, title = {Cross-diagnostic evaluation of minor physical anomalies in psychiatric disorders.}, journal = {J Psychiatr Res}, volume = {142}, year = {2021}, month = {2021 Jul 20}, pages = {54-62}, abstract = {

BACKGROUND: Minor physical anomalies (MPA) are markers of impaired neurodevelopment during the prenatal stage. Assessing MPA across psychiatric disorders may help understand their shared nature. In addition, MPA in family members would indicate a shared liability and endophenotype potential. We examined familial aggregation of MPA and their role as transdiagnostic and disorder-specific markers of 5 major psychiatric/neuropsychiatric conditions (schizophrenia, bipolar disorder, substance dependence, obsessive-compulsive disorder, and Alzheimer{\textquoteright}s dementia).

METHODS: Modified Waldrop{\textquoteright}s MPA scale was applied on 1321 individuals from 439 transdiagnostic multiplex families and 125 healthy population controls (HC). Stage of fetal development (morphogenetic/phenogenetic)- and anatomical location (craniofacial/peripheral)-based sub-scores were calculated. Familiality and endophenotypic potential of MPA were analyzed with serial negative binomial mixed-effect regression. Cross-diagnostic differences and the effect of family history density (FHD) of each diagnosis on MPA were assessed. Mixed-effects Cox models estimated the influence of MPA on age-at-onset of illness (AAO).

RESULTS: MPA were found to be heritable in families with psychiatric disorders, with a familiality of 0.52. MPA were higher in psychotic disorders after controlling for effects of sex and intrafamilial correlation. Morphogenetic variant MPA was noted to be lower in dementia in comparison to HC. FHD of schizophrenia and bipolar disorder predicted higher, and that of dementia and substance dependence predicted lower MPA. MPA brought forward the AAO [HR:1.07 (1.03-1.11)], and this was more apparent in psychotic disorders.

CONCLUSION: MPA are transmissible in families, are specifically related to the risk of developing psychoses, and predict an earlier age at onset. Neurodevelopmentally informed classification of MPA has the potential to enhance the etiopathogenic and translational understanding of psychiatric disorders.

}, issn = {1879-1379}, doi = {10.1016/j.jpsychires.2021.07.028}, author = {Sreeraj, Vanteemar S and Puzhakkal, Joan C and Holla, Bharath and Nadella, Ravi Kumar and Sheth, Sweta and Balachander, Srinivas and Ithal, Dhruva and Ali, Furkhan and Viswanath, Biju and Muralidharan, Kesavan and Venkatasubramanian, Ganesan and John, John P and Benegal, Vivek and Murthy, Pratima and Varghese, Mathew and Reddy, Yc Janardhan and Jain, Sanjeev} } @article {2327, title = {Engineered RNA biosensors enable ultrasensitive SARS-CoV-2 detection in a simple color and luminescence assay.}, journal = {Life Sci Alliance}, volume = {4}, year = {2021}, month = {2021 12}, abstract = {

The continued resurgence of the COVID-19 pandemic with multiple variants underlines the need for diagnostics that are adaptable to the virus. We have developed toehold RNA-based sensors across the SARS-CoV-2 genome for direct and ultrasensitive detection of the virus and its prominent variants. Here, isothermal amplification of a fragment of SARS-CoV-2 RNA coupled with activation of our biosensors leads to a conformational switch in the sensor. This leads to translation of a reporter protein, for example, LacZ or nano-lantern that is easily detected using color/luminescence. By optimizing RNA amplification and biosensor design, we have generated a highly sensitive diagnostic assay that is capable of detecting as low as 100 copies of viral RNA with development of bright color. This is easily visualized by the human eye and quantifiable using spectrophotometry. Finally, this PHAsed NASBA-Translation Optical Method (PHANTOM) using our engineered RNA biosensors efficiently detects viral RNA in patient samples. This work presents a powerful and universally accessible strategy for detecting COVID-19 and variants. This strategy is adaptable to further viral evolution and brings RNA bioengineering center-stage.

}, keywords = {Biosensing Techniques, COVID-19, Humans, Luminescence, Nucleic Acid Amplification Techniques, RNA, RNA, Viral, SARS-CoV-2}, issn = {2575-1077}, doi = {10.26508/lsa.202101213}, author = {Chakravarthy, Anirudh and Nandakumar, Anirudh and George, Geen and Ranganathan, Shyamsundar and Umashankar, Suchitta and Shettigar, Nishan and Palakodeti, Dasaradhi and Gulyani, Akash and Ramesh, Arati} } @article {2377, title = {Gene Editing in Human Induced Pluripotent Stem Cells Using Doxycycline-Inducible CRISPR-Cas9 System.}, journal = {Methods Mol Biol}, year = {2021}, month = {2021 Apr 09}, abstract = {

Induced pluripotent stem cells (iPSCs) generated from patients are a valuable tool for disease modelling, drug screening, and studying the functions of cell/tissue-specific genes. However, for this research, isogenic iPSC lines are important for comparison of phenotypes in the wild type and mutant differentiated cells generated from the iPSCs. The advent of gene editing technologies to correct or generate mutations helps in the generation of isogenic iPSC lines with the same genetic background. Due to the ease of programming, CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats)-Cas9-based gene editing tools have gained pace in gene manipulation studies, including investigating complex diseases like cancer. An iPSC line with drug inducible Cas9 expression from the Adeno-Associated Virus Integration Site 1 (AAVS1) safe harbor locus offers a controllable expression of Cas9 with robust gene editing. Here, we describe a stepwise protocol for the generation and characterization of such an iPSC line (AAVS1-PDi-Cas9 iPSC) with a doxycycline (dox)-inducible Cas9 expression cassette from the AAVS1 safe harbor site and efficient editing of target genes with lentiviral vectors expressing gRNAs. This approach with a tunable Cas9 expression that allows investigating gene functions in iPSCs or in the differentiated cells can serve as a versatile tool in disease modelling studies.

}, issn = {1940-6029}, doi = {10.1007/7651_2021_348}, author = {Thamodaran, Vasanth and Rani, Sonam and Velayudhan, Shaji R} } @article {2323, title = {Genomic characterization and epidemiology of an emerging SARS-CoV-2 variant in Delhi, India.}, journal = {Science}, year = {2021}, month = {2021 Oct 14}, pages = {eabj9932}, abstract = {

Delhi, the national capital of India, has experienced multiple SARS-CoV-2 outbreaks in 2020 and reached population seropositivity of over 50\% by 2021. During April 2021, the city became overwhelmed by COVID-19 cases and fatalities, as a new variant B.1.617.2 (Delta) replaced B.1.1.7 (Alpha). A Bayesian model explains the growth advantage of Delta through a combination of increased transmissibility and reduced sensitivity to immune responses generated against earlier variants (median estimates; {\texttimes}1.5-fold, 20\% reduction). Seropositivity of an employee and family cohort increased from 42\% to 87.5\% between March and July 2021, with 27\% reinfections, as judged by increased antibody concentration after a previous decline. The likely high transmissibility and partial evasion of immunity by the Delta variant contributed to an overwhelming surge in Delhi.

}, issn = {1095-9203}, doi = {10.1126/science.abj9932}, author = {Dhar, Mahesh S and Marwal, Robin and Vs, Radhakrishnan and Ponnusamy, Kalaiarasan and Jolly, Bani and Bhoyar, Rahul C and Sardana, Viren and Naushin, Salwa and Rophina, Mercy and Mellan, Thomas A and Mishra, Swapnil and Whittaker, Charles and Fatihi, Saman and Datta, Meena and Singh, Priyanka and Sharma, Uma and Ujjainiya, Rajat and Bhatheja, Nitin and Divakar, Mohit Kumar and Singh, Manoj K and Imran, Mohamed and Senthivel, Vigneshwar and Maurya, Ranjeet and Jha, Neha and Mehta, Priyanka and A, Vivekanand and Sharma, Pooja and Vr, Arvinden and Chaudhary, Urmila and Soni, Namita and Thukral, Lipi and Flaxman, Seth and Bhatt, Samir and Pandey, Rajesh and Dash, Debasis and Faruq, Mohammed and Lall, Hemlata and Gogia, Hema and Madan, Preeti and Kulkarni, Sanket and Chauhan, Himanshu and Sengupta, Shantanu and Kabra, Sandhya and Gupta, Ravindra K and Singh, Sujeet K and Agrawal, Anurag and Rakshit, Partha and Nandicoori, Vinay and Tallapaka, Karthik Bharadwaj and Sowpati, Divya Tej and Thangaraj, K and Bashyam, Murali Dharan and Dalal, Ashwin and Sivasubbu, Sridhar and Scaria, Vinod and Parida, Ajay and Raghav, Sunil K and Prasad, Punit and Sarin, Apurva and Mayor, Satyajit and Ramakrishnan, Uma and Palakodeti, Dasaradhi and Seshasayee, Aswin Sai Narain and Bhat, Manoj and Shouche, Yogesh and Pillai, Ajay and Dikid, Tanzin and Das, Saumitra and Maitra, Arindam and Chinnaswamy, Sreedhar and Biswas, Nidhan Kumar and Desai, Anita Sudhir and Pattabiraman, Chitra and Manjunatha, M V and Mani, Reeta S and Arunachal Udupi, Gautam and Abraham, Priya and Atul, Potdar Varsha and Cherian, Sarah S} } @article {2325, title = {Isolation and Quantification of Mouse γδT-cells and .}, journal = {Bio Protoc}, volume = {11}, year = {2021}, month = {2021 Sep 05}, pages = {e4148}, abstract = {

The skin plays an important role in protecting the body from pathogens and chemicals in the external environment. Upon injury, a healing program is rapidly initiated and involves extensive intercellular communication to restore tissue homeostasis. The deregulation of this crosstalk can lead to abnormal healing processes and is the foundation of many skin diseases. A relatively overlooked cell type that nevertheless plays critical roles in skin homeostasis, wound repair, and disease is the dendritic epidermal T cells (DETCs), which are also called γδT-cells. Given their varied roles in both physiological and pathological scenarios, interest in the regulation and function of DETCs has substantially increased. Moreover, their ability to regulate other immune cells has garnered substantial attention for their potential role as immunomodulators and in immunotherapies. In this article, we describe a protocol to isolate and culture DETCs and analyse them within the skin. These approaches will facilitate the investigation of their crosstalk with other cutaneous cells and the mechanisms by which they influence the status of the skin. Graphic abstract: Overall workflow to analyse DETCs and .

}, issn = {2331-8325}, doi = {10.21769/BioProtoc.4148}, author = {Rana, Isha and Badarinath, Krithika and Zirmire, Ravindra K and Jamora, Colin} } @article {2269, title = {Kog1/Raptor mediates metabolic rewiring during nutrient limitation by controlling SNF1/AMPK activity.}, journal = {Sci Adv}, volume = {7}, year = {2021}, month = {2021 Apr}, abstract = {

In changing environments, cells modulate resource budgeting through distinct metabolic routes to control growth. Accordingly, the TORC1 and SNF1/AMPK pathways operate contrastingly in nutrient replete or limited environments to maintain homeostasis. The functions of TORC1 under glucose and amino acid limitation are relatively unknown. We identified a modified form of the yeast TORC1 component Kog1/Raptor, which exhibits delayed growth exclusively during glucose and amino acid limitations. Using this, we found a necessary function for Kog1 in these conditions where TORC1 kinase activity is undetectable. Metabolic flux and transcriptome analysis revealed that Kog1 controls SNF1-dependent carbon flux apportioning between glutamate/amino acid biosynthesis and gluconeogenesis. Kog1 regulates SNF1/AMPK activity and outputs and mediates a rapamycin-independent activation of the SNF1 targets Mig1 and Cat8. This enables effective glucose derepression, gluconeogenesis activation, and carbon allocation through different pathways. Therefore, Kog1 centrally regulates metabolic homeostasis and carbon utilization during nutrient limitation by managing SNF1 activity.

}, issn = {2375-2548}, doi = {10.1126/sciadv.abe5544}, author = {Rashida, Zeenat and Srinivasan, Rajalakshmi and Cyanam, Meghana and Laxman, Sunil} } @article {2242, title = {Mechanical instability of adherens junctions overrides intrinsic quiescence of hair follicle stem cells.}, journal = {Dev Cell}, volume = {56}, year = {2021}, month = {2021 Mar 22}, pages = {761-780.e7}, abstract = {

Vinculin, a mechanotransducer associated with both adherens junctions (AJs) and focal adhesions (FAs), plays a central role in force transmission through cell-cell and cell-substratum contacts. We generated the conditional knockout (cKO) of vinculin in murine skin that results in the loss of bulge stem cell (BuSC) quiescence and promotes continual cycling of the hair follicles. Surprisingly, we find that the AJs in vinculin cKO cells are mechanically weak and impaired in force generation despite increased junctional expression of E-cadherin and α-catenin. Mechanistically, we demonstrate that vinculin functions by keeping α-catenin in a stretched/open conformation, which in turn regulates the retention of YAP1, another potent mechanotransducer and regulator of cell proliferation, at the AJs. Altogether, our data provide mechanistic insights into the hitherto-unexplored regulatory link between the mechanical stability of cell junctions and contact-inhibition-mediated maintenance of BuSC quiescence.

}, issn = {1878-1551}, doi = {10.1016/j.devcel.2021.02.020}, author = {Biswas, Ritusree and Banerjee, Avinanda and Lembo, Sergio and Zhao, Zhihai and Lakshmanan, Vairavan and Lim, Ryan and Le, Shimin and Nakasaki, Manando and Kutyavin, Vassily and Wright, Graham and Palakodeti, Dasaradhi and Ross, Robert S and Jamora, Colin and Vasioukhin, Valeri and Jie, Yan and Raghavan, Srikala} } @article {2244, title = {Oxylipin biosynthesis reinforces cellular senescence and allows detection of senolysis.}, journal = {Cell Metab}, year = {2021}, month = {2021 Mar 31}, abstract = {

Cellular senescence is a stress or damage response that causes a permanent proliferative arrest and secretion of numerous factors with potent biological activities. This senescence-associated secretory phenotype (SASP) has been characterized largely for secreted proteins that participate in embryogenesis, wound healing, inflammation, and many age-related pathologies. By contrast, lipid components of the SASP are understudied. We show that senescent cells activate the biosynthesis of several oxylipins that promote segments of the SASP and reinforce the proliferative arrest. Notably, senescent cells synthesize and accumulate an unstudied intracellular prostaglandin, 1a,1b-dihomo-15-deoxy-delta-12,14-prostaglandin J2. Released 15-deoxy-delta-12,14-prostaglandin J2 is a biomarker of senolysis in culture and in\ vivo. This and other prostaglandin D2-related lipids promote the senescence arrest and SASP by activating RAS signaling. These data identify an important aspect of cellular senescence and a method to detect senolysis.

}, issn = {1932-7420}, doi = {10.1016/j.cmet.2021.03.008}, author = {Wiley, Christopher D and Sharma, Rishi and Davis, Sonnet S and Lopez-Dominguez, Jose Alberto and Mitchell, Kylie P and Wiley, Samantha and Alimirah, Fatouma and Kim, Dong Eun and Payne, Therese and Rosko, Andrew and Aimontche, Eliezer and Deshpande, Sharvari M and Neri, Francesco and Kuehnemann, Chisaka and Demaria, Marco and Ramanathan, Arvind and Campisi, Judith} } @article {2401, title = {Pharmacological intervention in young adolescents rescues synaptic physiology and behavioural deficits in Syngap1 mice.}, journal = {Exp Brain Res}, year = {2021}, month = {2021 Nov 05}, abstract = {

Haploinsufficiency in SYNGAP1 is implicated in intellectual disability (ID) and autism spectrum disorder (ASD) and affects the maturation of dendritic spines. The abnormal spine development has been suggested to cause a disbalance of excitatory and inhibitory (E/I) neurotransmission at distinct developmental periods. In addition, E/I imbalances in Syngap1 mice might be due to abnormalities in K-Cl co-transporter function (NKCC1, KCC2), in a maner similar to the murine models of Fragile-X and Rett syndromes. To study whether an altered intracellular chloride ion concentration represents an underlying mechanism of modified function of GABAergic synapses in Dentate Gyrus Granule Cells of Syngap1 recordings were performed at different developmental stages of the mice. We observed depolarised neurons at P14-15 as illustrated by decreased Cl reversal potential in Syngap1 mice. The KCC2 expression was decreased compared to Wild-type (WT) mice at P14-15. The GSK-3β inhibitor, 6-bromoindirubin-3{\textquoteright}-oxime (6BIO) that crosses the blood-brain barrier, was tested to restore the function of GABAergic synapses. We discovered that the intraperitoneal administration of 6BIO during the critical period or young adolescents [P30 to P80 (4-week to 10-week)] normalised an altered E/I balance, the deficits of synaptic plasticity, and behavioural performance like social novelty, anxiety, and memory of the Syngap1 mice. In summary, altered GABAergic function in Syngap1 mice is due to reduced KCC2 expression leading to an increase in the intracellular chloride concentration that can be counteracted by the 6BIO, which restored cognitive, emotional, and social symptoms by pharmacological intervention, particularly in adulthood.

}, issn = {1432-1106}, doi = {10.1007/s00221-021-06254-x}, author = {Verma, Vijaya and Kumar, M J Vijay and Sharma, Kavita and Rajaram, Sridhar and Muddashetty, Ravi and Manjithaya, Ravi and Behnisch, Thomas and Clement, James P} } @article {2376, title = {Proteome plasticity in response to persistent environmental change.}, journal = {Mol Cell}, volume = {81}, year = {2021}, month = {2021 08 19}, pages = {3294-3309.e12}, abstract = {

Temperature is a variable component of the environment, and all organisms must deal with or adapt to temperature change. Acute temperature change activates cellular stress responses, resulting in refolding or removal of damaged proteins. However, how organisms adapt to long-term temperature change remains largely unexplored. Here we report that budding yeast responds to long-term high temperature challenge by switching from chaperone induction to reduction of temperature-sensitive proteins and re-localizing a portion of its proteome. Surprisingly, we also find that many proteins adopt an alternative conformation. Using Fet3p as an example, we find that the temperature-dependent conformational difference is accompanied by distinct thermostability, subcellular localization, and, importantly, cellular functions. We postulate that, in addition to the known mechanisms of adaptation, conformational plasticity allows some polypeptides to acquire new biophysical properties and functions when environmental change endures.

}, keywords = {Acclimatization, Adaptation, Physiological, Animals, Environmental Exposure, Gene Expression Regulation, Fungal, Hot Temperature, Proteome, Saccharomycetales, Stress, Physiological, Transcriptome}, issn = {1097-4164}, doi = {10.1016/j.molcel.2021.06.028}, author = {Domnauer, Matthew and Zheng, Fan and Li, Liying and Zhang, Yanxiao and Chang, Catherine E and Unruh, Jay R and Conkright-Fincham, Juliana and McCroskey, Scott and Florens, Laurence and Zhang, Ying and Seidel, Christopher and Fong, Benjamin and Schilling, Birgit and Sharma, Rishi and Ramanathan, Arvind and Si, Kausik and Zhou, Chuankai} } @article {2202, title = {Psychiatric symptoms and syndromes transcending diagnostic boundaries in Indian multiplex families: The cohort of ADBS study.}, journal = {Psychiatry Res}, volume = {296}, year = {2021}, month = {2021 Feb}, pages = {113647}, abstract = {

Syndromes of schizophrenia, bipolar disorder, obsessive-compulsive disorder, substance use disorders and Alzheimer{\textquoteright}s dementia are highly heritable. About 10-20\% of subjects have another affected first degree relative (FDR), and thus represent a {\textquoteright}greater{\textquoteright} genetic susceptibility. We screened 3583 families to identify 481 families with multiple affected members, assessed 1406 individuals in person, and collected information systematically about other relatives. Within the selected families, a third of all FDRs were affected with serious mental illness. Although similar diagnoses aggregated within families, 62\% of the families also had members with other syndromes. Moreover, 15\% of affected individuals met criteria for co-occurrence of two or more syndromes, across their lifetime. Using dimensional assessments, we detected a range of symptom clusters in both affected and unaffected individuals, and across diagnostic categories. Our findings suggest that in multiplex families, there is considerable heterogeneity of clinical syndromes, as well as sub-threshold symptoms. These families would help provide an opportunity for further research using both genetic analyses and biomarkers.

}, issn = {1872-7123}, doi = {10.1016/j.psychres.2020.113647}, author = {Sreeraj, Vanteemar S and Holla, Bharath and Ithal, Dhruva and Nadella, Ravi Kumar and Mahadevan, Jayant and Balachander, Srinivas and Ali, Furkhan and Sheth, Sweta and Narayanaswamy, Janardhanan C and Venkatasubramanian, Ganesan and John, John P and Varghese, Mathew and Benegal, Vivek and Jain, Sanjeev and Reddy, Yc Janardhan and Viswanath, Biju} } @article {2372, title = {Ribosomal protein S6 kinase beta-1 gene variants cause hypertrophic cardiomyopathy.}, journal = {J Med Genet}, year = {2021}, month = {2021 Dec 16}, abstract = {

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is a genetic heart muscle disease with preserved or increased ejection fraction in the absence of secondary causes. Mutations in the sarcomeric protein-encoding genes predominantly cause HCM. However, relatively little is known about the genetic impact of signalling proteins on HCM.

METHODS AND RESULTS: Here, using exome and targeted sequencing methods, we analysed two independent cohorts comprising 401 Indian patients with HCM and 3521 Indian controls. We identified novel variants in ribosomal protein S6 kinase beta-1 () gene in two unrelated Indian families as a potential candidate gene for HCM. The two unrelated HCM families had the same heterozygous missense S6K1 variant (p.G47W). In a replication association study, we identified two S6K1 heterozygotes variants (p.Q49K and p.Y62H) in the UK Biobank cardiomyopathy cohort (n=190) compared with matched controls (n=16 479). These variants are neither detected in region-specific controls nor in the human population genome data. Additionally, we observed an S6K1 variant (p.P445S) in an Arab patient with HCM. Functional consequences were evaluated using representative S6K1 mutated proteins compared with wild type in cellular models. The mutated proteins activated the S6K1 and hyperphosphorylated the rpS6 and ERK1/2 signalling cascades, suggesting a gain-of-function effect.

CONCLUSIONS: Our study demonstrates for the first time that the variants in the gene are associated with HCM, and early detection of the variant carriers can help to identify family members at risk and subsequent preventive measures. Further screening in patients with HCM with different ethnic populations will establish the specificity and frequency of gene variants.

}, issn = {1468-6244}, doi = {10.1136/jmedgenet-2021-107866}, author = {Jain, Pratul Kumar and Jayappa, Shashank and Sairam, Thiagarajan and Mittal, Anupam and Paul, Sayan and Rao, Vinay J and Chittora, Harshil and Kashyap, Deepak K and Palakodeti, Dasaradhi and Thangaraj, Kumarasamy and Shenthar, Jayaprakash and Koranchery, Rakesh and Rajendran, Ranjith and Alireza, Haghighi and Mohanan, Kurukkanparampil Sreedharan and Rathinavel, Andiappan and Dhandapany, Perundurai S} } @article {2363, title = {SARS-CoV-2 B.1.617.2 Delta variant replication and immune evasion.}, journal = {Nature}, volume = {599}, year = {2021}, month = {2021 11}, pages = {114-119}, abstract = {

The B.1.617.2 (Delta) variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was first identified in the state of Maharashtra in late 2020 and spread throughout India, outcompeting pre-existing lineages including B.1.617.1 (Kappa) and B.1.1.7 (Alpha). In vitro, B.1.617.2 is sixfold less sensitive to serum neutralizing antibodies from recovered individuals, and eightfold less sensitive to vaccine-elicited antibodies, compared with wild-type Wuhan-1 bearing D614G. Serum neutralizing titres against B.1.617.2 were lower in ChAdOx1 vaccinees than in BNT162b2 vaccinees. B.1.617.2 spike pseudotyped viruses exhibited compromised sensitivity to monoclonal antibodies to the receptor-binding domain and the amino-terminal domain. B.1.617.2 demonstrated higher replication efficiency than B.1.1.7 in both airway organoid and human airway epithelial systems, associated with B.1.617.2 spike being in a predominantly cleaved state compared with B.1.1.7 spike. The B.1.617.2 spike protein was able to mediate highly efficient syncytium formation that was less sensitive to inhibition by neutralizing antibody, compared with that of wild-type spike. We also observed that B.1.617.2 had higher replication and spike-mediated entry than B.1.617.1, potentially explaining the B.1.617.2 dominance. In an analysis of more than 130 SARS-CoV-2-infected health care workers across three centres in India during a period of mixed lineage circulation, we observed reduced ChAdOx1 vaccine effectiveness against B.1.617.2 relative to non-B.1.617.2, with the caveat of possible residual confounding. Compromised vaccine efficacy against the highly fit and immune-evasive B.1.617.2 Delta variant warrants continued infection control measures in the post-vaccination era.

}, keywords = {Antibodies, Neutralizing, Cell Fusion, Cell Line, COVID-19 Vaccines, Female, Health Personnel, Humans, Immune Evasion, India, Kinetics, Male, SARS-CoV-2, Spike Glycoprotein, Coronavirus, Vaccination, Virus Replication}, issn = {1476-4687}, doi = {10.1038/s41586-021-03944-y}, author = {Mlcochova, Petra and Kemp, Steven A and Dhar, Mahesh Shanker and Papa, Guido and Meng, Bo and Ferreira, Isabella A T M and Datir, Rawlings and Collier, Dami A and Albecka, Anna and Singh, Sujeet and Pandey, Rajesh and Brown, Jonathan and Zhou, Jie and Goonawardane, Niluka and Mishra, Swapnil and Whittaker, Charles and Mellan, Thomas and Marwal, Robin and Datta, Meena and Sengupta, Shantanu and Ponnusamy, Kalaiarasan and Radhakrishnan, Venkatraman Srinivasan and Abdullahi, Adam and Charles, Oscar and Chattopadhyay, Partha and Devi, Priti and Caputo, Daniela and Peacock, Tom and Wattal, Chand and Goel, Neeraj and Satwik, Ambrish and Vaishya, Raju and Agarwal, Meenakshi and Mavousian, Antranik and Lee, Joo Hyeon and Bassi, Jessica and Silacci-Fegni, Chiara and Saliba, Christian and Pinto, Dora and Irie, Takashi and Yoshida, Isao and Hamilton, William L and Sato, Kei and Bhatt, Samir and Flaxman, Seth and James, Leo C and Corti, Davide and Piccoli, Luca and Barclay, Wendy S and Rakshit, Partha and Agrawal, Anurag and Gupta, Ravindra K} } @article {2310, title = {Scanning electron microscopy of murine skin ultrathin sections and cultured keratinocytes.}, journal = {STAR Protoc}, volume = {2}, year = {2021}, month = {2021 Sep 17}, pages = {100729}, abstract = {

Generating high-quality electron microscopy images of the skin and keratinocytes can be challenging. Here we describe a simple protocol for scanning electron microscopy (SEM) of murine skin. The protocol enables characterization of the ultrastructure of the epidermis, dermis, hair follicles, basement membrane, and cell-cell junctions. We detail the specific steps for sample preparation and highlight the critical need for proper orientation of the sample for ultrathin sectioning. We also describe the isolation and preparation of primary keratinocyte monolayers for SEM. For complete details on the use and execution of this protocol, please refer to Biswas et\ al. (2021).

}, issn = {2666-1667}, doi = {10.1016/j.xpro.2021.100729}, author = {Banerjee, Avinanda and Biswas, Ritusree and Lim, Ryan and Pasolli, Hilda Amalia and Raghavan, Srikala} } @article {2200, title = {tRNA-derived fragments (tRFs): establishing their turf in post-transcriptional gene regulation.}, journal = {Cell Mol Life Sci}, year = {2021}, month = {2021 Jan 02}, abstract = {

Transfer RNA (tRNA)-derived fragments (tRFs) are an emerging class of conserved small non-coding RNAs that play important roles in post-transcriptional gene regulation. High-throughput sequencing of multiple biological samples have identified heterogeneous species of tRFs with distinct functionalities. These small RNAs have garnered a lot of scientific attention due to their ubiquitous expression and versatility in regulating various biological processes. In this review, we highlight our current understanding of tRF biogenesis and their regulatory functions. We summarize the diverse modes of biogenesis through which tRFs are generated and discuss the mechanism through which different tRF species regulate gene expression and the biological implications. Finally, we conceptualize research areas that require focus to strengthen our understanding of the biogenesis and function of tRFs.

}, issn = {1420-9071}, doi = {10.1007/s00018-020-03720-7}, author = {Krishna, Srikar and Raghavan, Srikala and DasGupta, Ramanuj and Palakodeti, Dasaradhi} } @article {2216, title = {A 2-Tyr-1-carboxylate Mononuclear Iron Center Forms the Active Site of a Paracoccus Dimethylformamidase.}, journal = {Angew Chem Int Ed Engl}, volume = {59}, year = {2020}, month = {2020 09 21}, pages = {16961-16966}, abstract = {

N,N-dimethyl formamide (DMF) is an extensively used organic solvent but is also a potent pollutant. Certain bacterial species from genera such as Paracoccus, Pseudomonas, and Alcaligenes have evolved to use DMF as a sole carbon and nitrogen source for growth via degradation by a dimethylformamidase (DMFase). We show that DMFase from Paracoccus sp. strain DMF is a halophilic and thermostable enzyme comprising a multimeric complex of the α β or (α β ) type. One of the three domains of the large subunit and the small subunit are hitherto undescribed protein folds of unknown evolutionary origin. The active site consists of a mononuclear iron coordinated by two Tyr side-chain phenolates and one carboxylate from Glu. The Fe ion in the active site catalyzes the hydrolytic cleavage of the amide bond in DMF. Kinetic characterization reveals that the enzyme shows cooperativity between subunits, and mutagenesis and structural data provide clues to the catalytic mechanism.

}, issn = {1521-3773}, doi = {10.1002/anie.202005332}, author = {Arya, Chetan Kumar and Yadav, Swati and Fine, Jonathan and Casanal, Ana and Chopra, Gaurav and Ramanathan, Gurunath and Vinothkumar, Kutti R and Subramanian, Ramaswamy} } @article {2156, title = {Adverse childhood experiences in families with multiple members diagnosed to have psychiatric illnesses.}, journal = {Aust N Z J Psychiatry}, volume = {54}, year = {2020}, month = {2020 Nov}, pages = {1086-1094}, abstract = {

OBJECTIVE: Adverse childhood experiences are linked to the development of a number of psychiatric illnesses in adulthood. Our study examined the pattern of adverse childhood experiences and their relation to the age of onset of major psychiatric conditions in individuals from families that had ⩾2 first-degree relatives with major psychiatric conditions (multiplex families), identified as part of an ongoing longitudinal study.

METHODS: Our sample consisted of 509 individuals from 215 families. Of these, 268 were affected, i.e., diagnosed with bipolar disorder ( = 61), obsessive-compulsive disorder ( = 58), schizophrenia ( = 52), substance dependence ( = 59) or co-occurring diagnoses ( = 38), while 241 were at-risk first-degree relatives who were either unaffected ( = 210) or had other depressive or anxiety disorders ( = 31). All individuals were evaluated using the Adverse Childhood Experiences - International Questionnaire and total adverse childhood experiences exposure and severity scores were calculated.

RESULTS: It was seen that affected males, as a group, had the greatest adverse childhood experiences exposure and severity scores in our sample. A Cox mixed effects model fit by gender revealed that a higher total adverse childhood experiences severity score was associated with significantly increased risk for an earlier age of onset of psychiatric diagnoses in males. A similar model that evaluated the interaction of diagnosis revealed an earlier age of onset in obsessive-compulsive disorder and substance dependence, but not in schizophrenia and bipolar disorder.

CONCLUSION: Our study indicates that adverse childhood experiences were associated with an earlier onset of major psychiatric conditions in men and individuals diagnosed with obsessive-compulsive disorder and substance dependence. Ongoing longitudinal assessments in first-degree relatives from these families are expected to identify mechanisms underlying this relationship.

}, issn = {1440-1614}, doi = {10.1177/0004867420931157}, author = {Someshwar, Amala and Holla, Bharath and Pansari Agarwal, Preeti and Thomas, Anza and Jose, Anand and Joseph, Boban and Raju, Birudu and Karle, Hariprasad and Muthukumaran, M and Kodancha, Prabhath G and Kumar, Pramod and Reddy, Preethi V and Kumar Nadella, Ravi and Naik, Sanjay T and Mitra, Sayantanava and Mallappagiri, Sreenivasulu and Sreeraj, Vanteemar S and Balachander, Srinivas and Ganesh, Suhas and Murthy, Pratima and Benegal, Vivek and Reddy, Janardhan Yc and Jain, Sanjeev and Mahadevan, Jayant and Viswanath, Biju} } @article {2062, title = {The Aging Metabolome-Biomarkers to Hub Metabolites.}, journal = {Proteomics}, volume = {20}, year = {2020}, month = {2020 03}, pages = {e1800407}, abstract = {

Aging biology is intimately associated with dysregulated metabolism, which is one of the hallmarks of aging. Aging-related pathways such as mTOR and AMPK, which are major targets of anti-aging interventions including rapamcyin, metformin, and exercise, either directly regulate or intersect with metabolic pathways. In this review, numerous candidate bio-markers of aging that have emerged using metabolomics are outlined. Metabolomics studies also reveal that not all metabolites are created equally. A set of core "hub" metabolites are emerging as central mediators of aging. The hub metabolites reviewed here are nicotinamide adenine dinucleotide, reduced nicotinamide dinucleotide phosphate, α-ketoglutarate, and β-hydroxybutyrate. These "hub" metabolites have signaling and epigenetic roles along with their canonical roles as co-factors or intermediates of carbon metabolism. Together these hub metabolites suggest a central role of the TCA cycle in signaling and metabolic dysregulation associated with aging.

}, issn = {1615-9861}, doi = {10.1002/pmic.201800407}, author = {Sharma, Rishi and Ramanathan, Arvind} } @article {1985, title = {Anabolic SIRT4 Exerts Retrograde Control over TORC1 Signaling by Glutamine Sparing in the Mitochondria.}, journal = {Mol Cell Biol}, volume = {40}, year = {2020}, month = {2020 Jan 03}, abstract = {

Anabolic and catabolic signaling mediated via mTOR and AMPK (AMP-activated kinase) have to be intrinsically coupled to mitochondrial functions for maintaining homeostasis and mitigate cellular/organismal stress. Although glutamine is known to activate mTOR, whether and how differential mitochondrial utilization of glutamine impinges on mTOR signaling has been less explored. Mitochondrial SIRT4, which unlike other sirtuins is induced in a fed state, is known to inhibit catabolic signaling/pathways through the AMPK-PGC1α/SIRT1-peroxisome proliferator-activated receptor α (PPARα) axis and negatively regulate glutamine metabolism via the tricarboxylic acid cycle. However, physiological significance of SIRT4 functions during a fed state is still unknown. Here, we establish SIRT4 as key anabolic factor that activates TORC1 signaling and regulates lipogenesis, autophagy, and cell proliferation. Mechanistically, we demonstrate that the ability of SIRT4 to inhibit anaplerotic conversion of glutamine to α-ketoglutarate potentiates TORC1. Interestingly, we also show that mitochondrial glutamine sparing or utilization is critical for differentially regulating TORC1 under fed and fasted conditions. Moreover, we conclusively show that differential expression of SIRT4 during fed and fasted states is vital for coupling mitochondrial energetics and glutamine utilization with anabolic pathways. These significant findings also illustrate that SIRT4 integrates nutrient inputs with mitochondrial retrograde signals to maintain a balance between anabolic and catabolic pathways.

}, issn = {1098-5549}, doi = {10.1128/MCB.00212-19}, author = {Shaw, Eisha and Talwadekar, Manasi and Rashida, Zeenat and Mohan, Nitya and Acharya, Aishwarya and Khatri, Subhash and Laxman, Sunil and Kolthur-Seetharam, Ullas} } @book {2246, title = {Bird Migration and Vector-Borne Parasite Transmission}, series = {Avian Malaria and Related Parasites in the Tropics. }, year = {2020}, publisher = {Springer}, organization = {Springer}, doi = {https://doi.org/10.1007/978-3-030-51633-8_16}, url = {https://link.springer.com/content/pdf/10.1007\%2F978-3-030-51633-8.pdf}, author = {Ishtiaq, Farah and Renner, S.C.} } @article {2217, title = {Comparison of CryoEM and X-ray structures of dimethylformamidase.}, journal = {Prog Biophys Mol Biol}, year = {2020}, month = {2020 Jul 28}, abstract = {

Dimethylformamidase (DMFase) catalyzes the hydrolysis of dimethylformamide, an industrial solvent, introduced into the environment by humans. Recently, we determined the structures of dimethylformamidase by electron cryo microscopy and X-ray crystallography revealing a tetrameric enzyme with a mononuclear iron at the active site. DMFase from Paracoccus sp. isolated from a waste water treatment plant around the city of Kanpur in India shows maximal activity at 54\ {\textdegree}C and is halotolerant. The structures determined by both techniques are mostly identical and the largest difference is in a loop near the active site. This loop could play a role in co-operativity between the monomers. A number of non-protein densities are observed in the EM map, which are modelled as water molecules. Comparison of the structures determined by the two methods reveals conserved water molecules that could play a structural role. The higher stability, unusual active site and negligible activity at low temperature makes this a very good model to study enzyme mechanism by cryoEM.

}, issn = {1873-1732}, doi = {10.1016/j.pbiomolbio.2020.06.008}, author = {Vinothkumar, Kutti R and Arya, Chetan Kumar and Ramanathan, Gurunath and Subramanian, Ramaswamy} } @article {2065, title = {Convolvulus pluricaulis extract can modulate synaptic plasticity in rat brain hippocampus.}, journal = {Neuroreport}, volume = {31}, year = {2020}, month = {2020 May 22}, pages = {597-604}, abstract = {

The memory-boosting property of Indian traditional herb, Convolvulus pluricaulis, has been documented in literature; however, its effect on synaptic plasticity has not yet been reported. Two important forms of synaptic plasticity known to be involved in the processes of memory formation are long-term potentiation (LTP) and long-term depression (LTD). In the present study, the effect of C. pluricaulis plant extract on LTP and LTD were evaluated. The adult male Wistar rats were fed orally with 250, 500 and 1000 mg/kg of this extract for 4 weeks and the effect was determined on LTP and LTD in the Schaffer collaterals of the hippocampal cornu ammonis region CA1. We found that the 500 mg/kg dose of the extract could significantly enhance LTP compared to the vehicle treated ones. Moreover, the same dose could also reduce LTD while used in a separate set of animals. Also, a fresh group of animals treated with the effective dose (500 mg/kg) of plant extract were examined for memory retention in two behavioral platforms namely, contextual fear conditioning (CFC) and novel object recognition test (NORT). Increased fear response to the conditioned stimulus and enhanced recognition of objects were observed in CFC and NORT, respectively, both indicating strengthening of memory. Following up, ex-vivo electrophysiology experiments were performed with the active single molecule scopoletin, present in C. pluricaulis extract and similar patterns in synaptic plasticity changes were obtained. These findings suggest that prolonged treatment of C. pluricaulis extract, at a specific dose in healthy animals, can augment memory functions by modulating hippocampal plasticity.

}, issn = {1473-558X}, doi = {10.1097/WNR.0000000000001446}, author = {Das, Rishi and Sengupta, Tathagata and Roy, Shubhrajit and Chattarji, Sumantra and Ray, Jharna} } @article {2110, title = {Cortical neurons derived from human pluripotent stem cells lacking FMRP display altered spontaneous firing patterns.}, journal = {Mol Autism}, volume = {11}, year = {2020}, month = {2020 Jun 19}, pages = {52}, abstract = {

BACKGROUND: Fragile X syndrome (FXS), a neurodevelopmental disorder, is a leading monogenetic cause of intellectual disability and autism spectrum disorder. Notwithstanding the extensive studies using rodent and other pre-clinical models of FXS, which have provided detailed mechanistic insights into the pathophysiology of this disorder, it is only relatively recently that human stem cell-derived neurons have been employed as a model system to further our understanding of the pathophysiological events that may underlie FXS. Our study assesses the physiological properties of human pluripotent stem cell-derived cortical neurons lacking fragile X mental retardation protein (FMRP).

METHODS: Electrophysiological whole-cell voltage- and current-clamp recordings were performed on two control and three FXS patient lines of human cortical neurons derived from induced pluripotent stem cells. In addition, we also describe the properties of an isogenic pair of lines in one of which FMR1 gene expression has been silenced.

RESULTS: Neurons lacking FMRP displayed bursts of spontaneous action potential firing that were more frequent but shorter in duration compared to those recorded from neurons expressing FMRP. Inhibition of large conductance Ca-activated K currents and the persistent Na current in control neurons phenocopies action potential bursting observed in neurons lacking FMRP, while in neurons lacking FMRP pharmacological potentiation of voltage-dependent Na channels phenocopies action potential bursting observed in control neurons. Notwithstanding the changes in spontaneous action potential firing, we did not observe any differences in the intrinsic properties of neurons in any of the lines examined. Moreover, we did not detect any differences in the properties of miniature excitatory postsynaptic currents in any of the lines.

CONCLUSIONS: Pharmacological manipulations can alter the action potential burst profiles in both control and FMRP-null human cortical neurons, making them appear like their genetic counterpart. Our studies indicate that FMRP targets that have been found in rodent models of FXS are also potential targets in a human-based model system, and we suggest potential mechanisms by which activity is altered.

}, issn = {2040-2392}, doi = {10.1186/s13229-020-00351-4}, author = {Das Sharma, Shreya and Pal, Rakhi and Reddy, Bharath Kumar and Selvaraj, Bhuvaneish T and Raj, Nisha and Samaga, Krishna Kumar and Srinivasan, Durga J and Ornelas, Loren and Sareen, Dhruv and Livesey, Matthew R and Bassell, Gary J and Svendsen, Clive N and Kind, Peter C and Chandran, Siddharthan and Chattarji, Sumantra and Wyllie, David J A} } @article {2146, title = {Differential flexibility leading to crucial microelastic properties of asymmetric lipid vesicles for cellular transfection: A combined spectroscopic and atomic force microscopy studies.}, journal = {Colloids Surf B Biointerfaces}, volume = {196}, year = {2020}, month = {2020 Sep 21}, pages = {111363}, abstract = {

The role of microscopic elasticity of nano-carriers in cellular uptake is an important aspect in biomedical research. Herein we have used AFM nano-indentation force spectroscopy and F{\"o}rster resonance energy transfer (FRET) measurements to probe microelastic properties of three novel cationic liposomes based on di-alkyl dihydroxy ethyl ammonium chloride based lipids having asymmetry in their hydrophobic chains (Lip1818, Lip1814 and Lip1810). AFM data reveals that symmetry in hydrophobic chains of a cationic lipid (Lip1818) imparts higher rigidity to the resulting liposomes than those based on asymmetric lipids (Lip1814 and Lip1810). The stiffness of the cationic liposomes is found to decrease with increasing asymmetry in the hydrophobic lipid chains in the order of Lip1818 \> Lip1814 \> lip1810. FRET measurements between Coumarin 500 (Donor) and Merocyanine 540 (Acceptor) have revealed that full width at half-maxima (hw) of the probability distribution (P(r)) of donor-acceptor distance (r), increases in an order Lip1818 \< Lip1814 \< Lip1810 with increasing asymmetry of the hydrophobic lipid chains. This increase in width (hw) of the donor-acceptor distance distributions is reflective of increasing flexibility of the liposomes with increasing asymmetry of their constituent lipids. Thus, the results from AFM and FRET studies are complementary to each other and indicates that an increase in asymmetry of the hydrophobic lipid chains increases elasticity and or flexibility of the corresponding liposomes. Cell biology experiments confirm that liposomal flexibility or rigidity directly influences their cellular transfection efficiency, where Lip1814 is found to be superior than the other two liposomes manifesting that a critical balance between flexibility and rigidity of the cationic liposomes is key to efficient cellular uptake. Taken together, our studies reveal how asymmetry in the molecular architecture of the hydrophobic lipid chains influences the microelastic properties of the liposomes, and hence, their cellular uptake efficiency.

}, issn = {1873-4367}, doi = {10.1016/j.colsurfb.2020.111363}, author = {Mukherjee, Dipanjan and Rakshit, Tatini and Singh, Priya and Mondal, Suman and Paul, Debashish and Ahir, Manisha and Adhikari, Arghya and Puthiyapurayil, Theja P and Vemula, Praveen Kumar and Senapati, Dulal and Das, Ranjan and Pal, Samir Kumar} } @article {2148, title = {Genetically encoded live-cell sensor for tyrosinated microtubules.}, journal = {J Cell Biol}, volume = {219}, year = {2020}, month = {2020 Oct 05}, abstract = {

Microtubule cytoskeleton exists in various biochemical forms in different cells due to tubulin posttranslational modifications (PTMs). Tubulin PTMs are known to affect microtubule stability, dynamics, and interaction with MAPs and motors in a specific manner, widely known as tubulin code hypothesis. At present, there exists no tool that can specifically mark tubulin PTMs in living cells, thus severely limiting our understanding of their dynamics and cellular functions. Using a yeast display library, we identified a binder against terminal tyrosine of α-tubulin, a unique PTM site. Extensive characterization validates the robustness and nonperturbing nature of our binder as tyrosination sensor, a live-cell tubulin nanobody specific towards tyrosinated microtubules. Using this sensor, we followed nocodazole-, colchicine-, and vincristine-induced depolymerization events of tyrosinated microtubules in real time and found each distinctly perturbs the microtubule polymer. Together, our work describes a novel tyrosination sensor and its potential applications to study the dynamics of microtubule and their PTM processes in living cells.

}, issn = {1540-8140}, doi = {10.1083/jcb.201912107}, author = {Kesarwani, Shubham and Lama, Prakash and Chandra, Anchal and Reddy, P Purushotam and Jijumon, A S and Bodakuntla, Satish and Rao, Balaji M and Janke, Carsten and Das, Ranabir and Sirajuddin, Minhajuddin} } @article {2203, title = {Genome-scale reconstruction of Gcn4/ATF4 networks driving a growth program.}, journal = {PLoS Genet}, volume = {16}, year = {2020}, month = {2020 12}, pages = {e1009252}, abstract = {

Growth and starvation are considered opposite ends of a spectrum. To sustain growth, cells use coordinated gene expression programs and manage biomolecule supply in order to match the demands of metabolism and translation. Global growth programs complement increased ribosomal biogenesis with sufficient carbon metabolism, amino acid and nucleotide biosynthesis. How these resources are collectively managed is a fundamental question. The role of the Gcn4/ATF4 transcription factor has been best studied in contexts where cells encounter amino acid starvation. However, high Gcn4 activity has been observed in contexts of rapid cell proliferation, and the roles of Gcn4 in such growth contexts are unclear. Here, using a methionine-induced growth program in yeast, we show that Gcn4/ATF4 is the fulcrum that maintains metabolic supply in order to sustain translation outputs. By integrating matched transcriptome and ChIP-Seq analysis, we decipher genome-wide direct and indirect roles for Gcn4 in this growth program. Genes that enable metabolic precursor biosynthesis indispensably require Gcn4; contrastingly ribosomal genes are partly repressed by Gcn4. Gcn4 directly binds promoter-regions and transcribes a subset of metabolic genes, particularly driving lysine and arginine biosynthesis. Gcn4 also globally represses lysine and arginine enriched transcripts, which include genes encoding the translation machinery. The Gcn4 dependent lysine and arginine supply thereby maintains the synthesis of the translation machinery. This is required to maintain translation capacity. Gcn4 consequently enables metabolic-precursor supply to bolster protein synthesis, and drive a growth program. Thus, we illustrate how growth and starvation outcomes are both controlled using the same Gcn4 transcriptional outputs that function in distinct contexts.

}, keywords = {Basic-Leucine Zipper Transcription Factors, Cell Proliferation, Gene Expression Regulation, Fungal, Gene Regulatory Networks, Genome, Fungal, Ribosomes, Saccharomyces cerevisiae, Saccharomyces cerevisiae Proteins, Transcriptional Activation}, issn = {1553-7404}, doi = {10.1371/journal.pgen.1009252}, author = {Srinivasan, Rajalakshmi and Walvekar, Adhish S and Rashida, Zeenat and Seshasayee, Aswin and Laxman, Sunil} } @article {2208, title = {Metabolic control of cellular immune-competency by odors in .}, journal = {Elife}, volume = {9}, year = {2020}, month = {2020 12 29}, abstract = {

Studies in different animal model systems have revealed the impact of odors on immune cells; however, any understanding on why and how odors control cellular immunity remained unclear. We find that employ an olfactory-immune cross-talk to tune a specific cell type, the lamellocytes, from hematopoietic-progenitor cells. We show that neuronally released GABA derived upon olfactory stimulation is utilized by blood-progenitor cells as a metabolite and through its catabolism, these cells stabilize Sima/HIFα protein. Sima capacitates blood-progenitor cells with the ability to initiate lamellocyte differentiation. This systemic axis becomes relevant for larvae dwelling in wasp-infested environments where chances of infection are high. By co-opting the olfactory route, the preconditioned animals elevate their systemic GABA levels leading to the upregulation of blood-progenitor cell Sima expression. This elevates their immune-potential and primes them to respond rapidly when infected with parasitic wasps. The present work highlights the importance of the olfaction in immunity and shows how odor detection during animal development is utilized to establish a long-range axis in the control of blood-progenitor competency and immune-priming.

}, issn = {2050-084X}, doi = {10.7554/eLife.60376}, author = {Madhwal, Sukanya and Shin, Mingyu and Kapoor, Ankita and Goyal, Manisha and Joshi, Manish K and Ur Rehman, Pirzada Mujeeb and Gor, Kavan and Shim, Jiwon and Mukherjee, Tina} } @article {2108, title = {A novel polyubiquitin chain linkage formed by viral Ubiquitin is resistant to host deubiquitinating enzymes.}, journal = {Biochem J}, volume = {477}, year = {2020}, month = {2020 Jun 26}, pages = {2193-2219}, abstract = {

The Baculoviridae family of viruses encode a viral Ubiquitin (vUb) gene. Though the vUb is homologous to the host eukaryotic Ubiquitin (Ub), its preservation in the viral genome indicates unique functions that are not compensated by the host Ub. We report the structural, biophysical, and biochemical properties of the vUb from Autographa californica multiple nucleo-polyhedrosis virus (AcMNPV). The packing of central helix α1 to the beta-sheet β1-β5 is different between vUb and Ub. Consequently, its stability is lower compared with Ub. However, the surface properties, ubiquitination activity, and the interaction with Ubiquitin-binding domains are similar between vUb and Ub. Interestingly, vUb forms atypical polyubiquitin chain linked by lysine at the 54th position (K54), and the deubiquitinating enzymes are ineffective against the K54-linked polyubiquitin chains. We propose that the modification of host/viral proteins with the K54-linked chains is an effective way selected by the virus to protect the vUb signal from host DeUbiquitinases.

}, issn = {1470-8728}, doi = {10.1042/BCJ20200289}, author = {Negi, Hitendra and Reddy, Pothula Purushotham and Vengayil, Vineeth and Patole, Chhaya and Laxman, Sunil and Das, Ranabir} } @article {2063, title = {N-terminal variant Asp14Asn of the human p70 S6 Kinase 1 enhances translational signaling causing different effects in developing and mature neuronal cells.}, journal = {Neurobiol Learn Mem}, volume = {171}, year = {2020}, month = {2020 May}, pages = {107203}, abstract = {

The ribosomal p70 S6 Kinase 1 (S6K1) has been implicated in the etiology of complex neurological diseases including autism, depression and dementia. Though no major gene disruption has been reported in humans in RPS6KB1, single nucleotide variants (SNVs) causing missense mutations have been identified, which have not been assessed for their impact on protein function. These S6K1 mutations have the potential to influence disease progression and treatment response. We mined the Simon Simplex Collection (SSC) and SPARK autism database to find inherited SNVs in S6K1 and characterized the effect of two missense SNVs, Asp14Asn (allele frequency\ =\ 0.03282\%) and Glu44Gln (allele frequency\ =\ 0.0008244\%), on S6K1 function in HEK293, human ES cells and primary neurons. Expressing Asp14Asn in HEK293 cells resulted in increased basal phosphorylation of downstream targets of S6K1 and increased de novo translation. This variant also showed blunted response to the specific S6K1 inhibitor, FS-115. In human embryonic cell line Shef4, Asp14Asn enhanced spontaneous neural fate specification in the absence of differentiating growth factors. In addition to enhanced translation, neurons expressing Asp14Asn exhibited impaired dendritic arborization and increased levels of phosphorylated ERK 1/2. Finally, in the SSC families tracked, Asp14Asn segregated with lower IQ scores when found in the autistic individual rather than the unaffected sibling. The Glu44Gln mutation showed a milder, but opposite phenotype in HEK cells as compared to Asp14Asn. Although the Glu44Gln mutation displayed increased neuronal translation, it had no impact on neuronal morphology. Our results provide the first characterization of naturally occurring human S6K1 variants on cognitive phenotype, neuronal morphology and maturation, underscoring again the importance of translation control in neural development and plasticity.

}, issn = {1095-9564}, doi = {10.1016/j.nlm.2020.107203}, author = {Venkatasubramani, Janani Priya and Subramanyam, Prakash and Pal, Rakhi and Reddy, Bharath K and Srinivasan, Durga Jeyalakshmi and Chattarji, Sumantra and Iossifov, Ivan and Klann, Eric and Bhattacharya, Aditi} } @article {2059, title = {The Role of Dynamic miRISC During Neuronal Development.}, journal = {Front Mol Biosci}, volume = {7}, year = {2020}, month = {2020}, pages = {8}, abstract = {

Activity-dependent protein synthesis plays an important role during neuronal development by fine-tuning the formation and function of neuronal circuits. Recent studies have shown that miRNAs are integral to this regulation because of their ability to control protein synthesis in a rapid, specific and potentially reversible manner. miRNA mediated regulation is a multistep process that involves inhibition of translation before degradation of targeted mRNA, which provides the possibility to store and reverse the inhibition at multiple stages. This flexibility is primarily thought to be derived from the composition of miRNA induced silencing complex (miRISC). AGO2 is likely the only obligatory component of miRISC, while multiple RBPs are shown to be associated with this core miRISC to form diverse miRISC complexes. The formation of these heterogeneous miRISC complexes is intricately regulated by various extracellular signals and cell-specific contexts. In this review, we discuss the composition of miRISC and its functions during neuronal development. Neurodevelopment is guided by both internal programs and external cues. Neuronal activity and external signals play an important role in the formation and refining of the neuronal network. miRISC composition and diversity have a critical role at distinct stages of neurodevelopment. Even though there is a good amount of literature available on the role of miRNAs mediated regulation of neuronal development, surprisingly the role of miRISC composition and its functional dynamics in neuronal development is not much discussed. In this article, we review the available literature on the heterogeneity of the neuronal miRISC composition and how this may influence translation regulation in the context of neuronal development.

}, issn = {2296-889X}, doi = {10.3389/fmolb.2020.00008}, author = {Nawalpuri, Bharti and Ravindran, Sreenath and Muddashetty, Ravi S} } @article {2201, title = {Staying connected under tension.}, journal = {Science}, volume = {370}, year = {2020}, month = {2020 11 27}, pages = {1036-1037}, keywords = {Mechanotransduction, Cellular, Microfilament Proteins}, issn = {1095-9203}, doi = {10.1126/science.abf2782}, author = {Raghavan, Srikala and Vasioukhin, Valeri} } @article {2064, title = {Temporal specificity and heterogeneity of Drosophila immune cells.}, journal = {EMBO J}, year = {2020}, month = {2020 Mar 12}, pages = {e104486}, abstract = {

Immune cells provide defense against non-self and have recently been shown to also play key roles in diverse processes such as development, metabolism, and tumor progression. The heterogeneity of Drosophila immune cells (hemocytes) remains an open question. Using bulk RNA sequencing, we find that the hemocytes display distinct features in the embryo, a closed and rapidly developing system, compared to the larva, which is exposed to environmental and metabolic challenges. Through single-cell RNA sequencing, we identify fourteen hemocyte clusters present in unchallenged larvae and associated with distinct processes, e.g., proliferation, phagocytosis, metabolic homeostasis, and humoral response. Finally, we characterize the changes occurring in the hemocyte clusters upon wasp infestation, which triggers the differentiation of a novel hemocyte type, the lamellocyte. This first molecular atlas of hemocytes provides insights and paves the way to study the biology of the Drosophila immune cells in physiological and pathological conditions.

}, issn = {1460-2075}, doi = {10.15252/embj.2020104486}, author = {Cattenoz, Pierre B and Sakr, Rosy and Pavlidaki, Alexia and Delaporte, Claude and Riba, Andrea and Molina, Nacho and Hariharan, Nivedita and Mukherjee, Tina and Giangrande, Angela} } @article {2039, title = {Temporal specificity and heterogeneity of the fly immune cells{\textquoteright} transcriptional landscape}, journal = {The EMBO Journal (in press)}, year = {2020}, abstract = {

Immune cells provide defense against the non-self, however recent data suggest roles well beyond innate immunity, in processes as diverse as development, metabolism and tumor progression. Nevertheless, the heterogeneity of these cells remains an open question. Using bulk RNA sequencing we find that the Drosophila immune cells (hemocytes) display distinct features in the embryo, a closed and rapidly developing system, compared to the larva, which is exposed to environmental and metabolic challenges. Through single cell RNA sequencing we identify fourteen hemocyte clusters present in unchallenged larvae and associated with distinct cellular processes e.g. proliferation, phagocytosis, metabolic homeostasis and humoral response. Finally, we characterize the changes occurring in the hemocyte clusters upon wasp infestation that triggers the differentiation of a novel cell type, the lamellocyte. This first molecular atlas provides precious insights and paves the way to study the biology of the Drosophila immune cells in physiological and pathological conditions.

}, author = {Cattenoz, Pierre B. and Sakr, Rosy and Pavlidaki, Alexia and Delaporte, Claude and Riba, Andrea and Molina, Nacho and Hariharan, Nivedita and Mukherjee, Tina and Giangrande, Angela} } @article {2210, title = {VEGFA Promoter Polymorphisms rs699947 and rs35569394 Are Associated With the Risk of Anterior Cruciate Ligament Ruptures Among Indian Athletes: A Cross-sectional Study.}, journal = {Orthop J Sports Med}, volume = {8}, year = {2020}, month = {2020 Dec}, pages = {2325967120964472}, abstract = {

Background: Associations of genetic variants within certain fibril-forming genes have previously been observed with anterior cruciate ligament (ACL) injuries. Evidence suggests a significant role of angiogenesis-associated cytokines in remodeling the ligament fibril matrix after mechanical loading and maintaining structural and functional integrity of the ligament. Functional polymorphisms within the vascular endothelial growth factor A (VEGFA) gene have emerged as plausible candidates owing to their role in the regulation of angiogenic responses.

Hypothesis: VEGFA promoter polymorphisms rs699947 and rs35569394 are associated with ACL injury risk among athletes.

Study Design: Cross-sectional study; Level of evidence, 3.

Methods: A total of 90 Indian athletes with radiologically confirmed or surgically proven isolated ACL tears and 76 matched-control athletes were selected for the present cross-sectional genetic association study. Oral mouthwash samples were collected from all the case and control athletes and genotyped for VEGFA rs699947 and rs35569394 using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method.

Results: The A allele (rs699947) was significantly overrepresented in the ACL group (C vs A allele: odds ratio [OR], 1.68 [95\% CI, 1.08-2.60]; = .021) (CC vs CA + AA: OR, 2.69 [95\% CI, 1.37-5.26]; = .004). There was a greater frequency of the AA genotype in the ACL group in comparison with the control group (OR, 3.38 [95\% CI, 1.23-9.28]; = .016) when only male athletes were compared. Likewise, there was a greater frequency of the I allele (rs35569394) in the ACL group (D vs I allele: OR, 1.64 [95\% CI, 1.06-2.55]; = .025) (DD vs ID + II: OR, 2.61 [95\% CI, 1.31-5.21]; = .006). The A-I haplotype was overrepresented in the ACL group compared with the control group (OR, 1.68 [95\% CI, 1.08-2.60]; χ = 5.320; = .021), and both the polymorphisms were found to be in complete linkage disequilibrium ( = 0.929; logarithm of the odds score = 63.74; D{\textquoteright} = 1.0). Female athletes did not show any difference in genotype or allele frequency.

Conclusion: This is the first study to investigate the association of VEGFA promoter polymorphisms in ACL tears among Indian athletes. Increased frequencies of the A allele (rs699947) and I allele (rs35569394) were observed in the ACL group. These results suggest that sequence variants in the VEGF gene are associated with ACL injury risk among athletes. Further research with long-term follow-ups measuring VEGF expression levels during recovery is warranted to establish its role in ACL injuries and healing.

}, issn = {2325-9671}, doi = {10.1177/2325967120964472}, author = {Shukla, Manish and Gupta, Rahul and Pandey, Vivek and Rochette, Jacques and Dhandapany, Perundurai S and Tiwari, Pramod Kumar and Amrathlal, Rabbind Singh} } @article {1646, title = {BDNF Induced Translation of Limk1 in Developing Neurons Regulates Dendrite Growth by Fine-Tuning Cofilin1 Activity.}, journal = {Front Mol Neurosci}, volume = {12}, year = {2019}, month = {2019}, pages = {64}, abstract = {

Dendritic growth and branching are highly regulated processes and are essential for establishing proper neuronal connectivity. There is a critical phase of early dendrite development when these are heavily regulated by external cues such as trophic factors. Brain-derived neurotrophic factor (BDNF) is a major trophic factor known to enhance dendrite growth in cortical neurons, but the molecular underpinnings of this response are not completely understood. We have identified that BDNF induced translational regulation is an important mechanism governing dendrite development in cultured rat cortical neurons. We show that BDNF treatment for 1 h in young neurons leads to translational up-regulation of an important actin regulatory protein LIM domain kinase 1 (Limk1), increasing its level locally in the dendrites. Limk1 is a member of serine/threonine (Ser/Thr) family kinases downstream of the Rho-GTPase pathway. BDNF induced increase in Limk1 levels leads to increased phosphorylation of its target protein cofilin1. We observed that these changes are maintained for long durations of up to 48 h and are mediating increase in number of primary dendrites and total dendrite length. Thus, we show that BDNF induced protein synthesis leads to fine-tuning of the actin cytoskeletal reassembly and thereby mediate dendrite development.

}, issn = {1662-5099}, doi = {10.3389/fnmol.2019.00064}, author = {Ravindran, Sreenath and Nalavadi, Vijayalaxmi C and Muddashetty, Ravi S} } @article {1734, title = {Characterization of new variant human ES line VH9 hESC (INSTEMe001-a): a tool for human stem cell and cancer research.}, journal = {Stem Cell Res}, volume = {37}, year = {2019}, month = {2019 May}, pages = {101444}, abstract = {

Human pluripotent stem cells (hPSCs) acquire changes at the genomic level upon proliferation and differentiation (Peterson and Loring, 2014). Studies from International Stem Cell Initiative and independent laboratories identified a copy number variant (CNV) in hES cell lines displaying a normal karyotype, which provided a selective advantage to hES cells in culture. In our laboratory we have identified variant H9-hESC (derived from H9-hESC) with normal karyotype, pluripotency expression, differentiation profile but with altered traits of high cell survival and low E-CADHERIN expression.

}, issn = {1876-7753}, doi = {10.1016/j.scr.2019.101444}, author = {Arasala, Radhika Rao and Jayaram, Manjunath and Chattai, Jagamohan and Kumarasamy, Thangaraj and Sambasivan, Ramkumar and Rampalli, Shravanti} } @article {1737, title = {Cytoplasmic sequestration of the RhoA effector mDiaphanous1 by Prohibitin2 promotes muscle differentiation.}, journal = {Sci Rep}, volume = {9}, year = {2019}, month = {2019 Jun 05}, pages = {8302}, abstract = {

Muscle differentiation is controlled by adhesion and growth factor-dependent signalling through common effectors that regulate muscle-specific transcriptional programs. Here we report that mDiaphanous1, an effector of adhesion-dependent RhoA-signalling, negatively regulates myogenesis at the level of Myogenin expression. In myotubes, over-expression of mDia1ΔN3, a RhoA-independent mutant, suppresses Myogenin promoter activity and expression. We investigated mDia1-interacting proteins that may counteract mDia1 to permit Myogenin expression and timely differentiation. Using yeast two-hybrid and mass-spectrometric analysis, we report that mDia1 has a stage-specific interactome, including Prohibitin2, MyoD, Akt2, and β-Catenin, along with a number of proteosomal and mitochondrial components. Of these interacting partners, Prohibitin2 colocalises with mDia1 in cytoplasmic punctae in myotubes. We mapped the interacting domains of mDia1 and Phb2, and used interacting (mDia1ΔN3/Phb2 FL or mDia1ΔN3/Phb2-Carboxy) and non-interacting pairs (mDia1H + P/Phb2 FL or mDia1ΔN3/Phb2-Amino) to dissect the functional consequences of this partnership on Myogenin promoter activity. Co-expression of full-length as well as mDia1-interacting domains of Prohibitin2 reverse the anti-myogenic effects of mDia1ΔN3, while non-interacting regions do not. Our results suggest that Prohibitin2 sequesters mDia1, dampens its anti-myogenic activity and fine-tunes RhoA-mDia1 signalling to promote differentiation. Overall, we report that mDia1 is multi-functional signalling effector whose anti-myogenic activity is modulated by a differentiation-dependent interactome.\ The data have been deposited to the ProteomeXchange with identifier PXD012257.

}, issn = {2045-2322}, doi = {10.1038/s41598-019-44749-4}, author = {Saleh, Amena and Subramaniam, Gunasekaran and Raychaudhuri, Swasti and Dhawan, Jyotsna} } @article {1740, title = {Dynamic expression of tRNA-derived small RNAs define cellular states.}, journal = {EMBO Rep}, volume = {20}, year = {2019}, month = {2019 Jul}, pages = {e47789}, abstract = {

Transfer RNA (tRNA)-derived small RNAs (tsRNAs) have recently emerged as important regulators of protein translation and shown to have diverse biological functions. However, the underlying cellular and molecular mechanisms of tsRNA function in the context of dynamic cell-state transitions remain unclear. Expression analysis of tsRNAs in distinct heterologous cell and tissue models of stem vs. differentiated states revealed a differentiation-dependent enrichment of 5{\textquoteright}-tsRNAs. We report the identification of a set of 5{\textquoteright}-tsRNAs that is upregulated in differentiating mouse embryonic stem cells (mESCs). Notably, interactome studies with differentially enriched 5{\textquoteright}-tsRNAs revealed a switch in their association with "effector" RNPs and "target" mRNAs in different cell states. We demonstrate that specific 5{\textquoteright}-tsRNAs can preferentially interact with the RNA-binding protein, Igf2bp1, in the RA-induced differentiated state. This association influences the transcript stability and thereby translation of the pluripotency-promoting factor, c-Myc, thus providing a mechanistic basis for how 5{\textquoteright}-tsRNAs can modulate stem cell states in mESCs. Together our study highlights the role of 5{\textquoteright}-tsRNAs in defining distinct cell states.

}, issn = {1469-3178}, doi = {10.15252/embr.201947789}, author = {Krishna, Srikar and Yim, Daniel Gr and Lakshmanan, Vairavan and Tirumalai, Varsha and Koh, Judice Ly and Park, Jung Eun and Cheong, Jit Kong and Low, Joo Leng and Lim, Michelle Js and Sze, Siu Kwan and Shivaprasad, Padubidri and Gulyani, Akash and Raghavan, Srikala and Palakodeti, Dasaradhi and DasGupta, Ramanuj} } @article {1934, title = {The E3 ubiquitin ligase Pib1 regulates effective gluconeogenic shutdown upon glucose availability.}, journal = {J Biol Chem}, year = {2019}, month = {2019 Oct 11}, abstract = {

Cells use multiple mechanisms to regulate their metabolic states in response to changes in their nutrient environment. One example is the response of cells to glucose. In S. cerevisiae growing in glucose-depleted medium, the re-availability of glucose leads to the downregulation of gluconeogenesis, and the activation of glycolysis, leading to {\textquoteright}glucose repression{\textquoteright}. However, our knowledge of the mechanisms mediating the glucose dependent downregulation of the gluconeogenic transcription factors is limited. Using a major gluconeogenic transcription factor Rds2 as a candidate, here we identify a novel role for the E3 ubiquitin ligase Pib1 in regulating the stability and degradation of Rds2. Glucose addition to cells growing in glucose limitation results in rapid ubiquitination of Rds2, followed by its proteasomal degradation. Through in vivo and in vitro experiments, we establish Pib1 as the ubiquitin E3 ligase that regulates Rds2 ubiquitination and stability. Notably, this Pib1 mediated Rds2 ubiquitination, followed by proteasomal degradation, is specific to the presence of glucose. This Pib1 mediated ubiquitination of Rds2 depends on the phosphorylation state of Rds2, suggesting a cross-talk between ubiquitination and phosphorylation to achieve a metabolic state change. Using stable-isotope based metabolic flux experiments we find that the loss of Pib1 results in an imbalanced gluconeogenic state, regardless of glucose availability. Pib1 is required for complete glucose repression, and enables cells to optimally grow in competitive environments when glucose becomes re-available. Our results reveal the existence of a Pib1 mediated regulatory program that mediates glucose-repression when glucose availability is restored.

}, issn = {1083-351X}, doi = {10.1074/jbc.RA119.009822}, author = {Vengayil, Vineeth and Rashida, Zeenat and Laxman, Sunil} } @article {1611, title = {Emerging Role of microRNAs in Dementia.}, journal = {J Mol Biol}, year = {2019}, month = {2019 Feb 07}, abstract = {

MicroRNAs are small non-coding RNAs regulating mRNA translation. They play a crucial role in regulating homeostasis in neurons, especially in regulating local and stimulation dependent protein synthesis. Since activity-mediated protein synthesis in neurons is critical for memory and cognition, microRNAs have become key players in modulating these processes. Dementia is a broad term used for symptoms involving decline of memory and cognition. Several studies have implicated the dysregulation of microRNAs in many brain diseases like neurodegenerative diseases, neurodevelopmental disorders, brain injuries and dementia. In this review, we give an overview of microRNA-mediated regulation of proteins and cellular processes affected in dementia pathology, hence illustrating the importance of microRNAs in normal functioning. We also focus on a relatively less explored area in dementia pathology-the importance of activity-mediated protein synthesis at the synapse and the role of microRNAs in modulating this. Overall, this review will be helpful in looking at the significance of microRNAs in dementia from the perspective of defective regulation of protein synthesis and synaptic dysfunction.

}, issn = {1089-8638}, doi = {10.1016/j.jmb.2019.01.046}, author = {Ramakrishna, Sarayu and Muddashetty, Ravi S} } @article {1603, title = {Enhancement of the gut barrier integrity by a microbial metabolite through the Nrf2 pathway.}, journal = {Nat Commun}, volume = {10}, year = {2019}, month = {2019 01 09}, pages = {89}, abstract = {

The importance of gut microbiota in human health and pathophysiology is undisputable. Despite the abundance of metagenomics data, the functional dynamics of gut microbiota in human health and disease remain elusive. Urolithin A (UroA), a major microbial metabolite derived from polyphenolics of berries and pomegranate fruits displays anti-inflammatory, anti-oxidative, and anti-ageing activities. Here, we show that UroA and its potent synthetic analogue (UAS03) significantly enhance gut barrier function and inhibit unwarranted inflammation. We demonstrate that UroA and UAS03 exert their barrier functions through activation of aryl hydrocarbon receptor (AhR)- nuclear factor erythroid 2-related factor 2 (Nrf2)-dependent pathways to upregulate epithelial tight junction proteins. Importantly, treatment with these compounds attenuated colitis in pre-clinical models by remedying barrier dysfunction in addition to anti-inflammatory activities. Cumulatively, the results highlight how microbial metabolites provide two-pronged beneficial activities at gut epithelium by enhancing barrier functions and reducing inflammation to protect from colonic diseases.

}, keywords = {Animals, Basic Helix-Loop-Helix Transcription Factors, Caco-2 Cells, Coumarins, Epithelial Cells, Gene Expression Regulation, HT29 Cells, Humans, Intestinal Mucosa, Macrophages, Mice, Mice, Inbred C57BL, Mice, Knockout, NF-E2-Related Factor 2, Receptors, Aryl Hydrocarbon, Specific Pathogen-Free Organisms, Tight Junction Proteins}, issn = {2041-1723}, doi = {10.1038/s41467-018-07859-7}, author = {Singh, Rajbir and Chandrashekharappa, Sandeep and Bodduluri, Sobha R and Baby, Becca V and Hegde, Bindu and Kotla, Niranjan G and Hiwale, Ankita A and Saiyed, Taslimarif and Patel, Paresh and Vijay-Kumar, Matam and Langille, Morgan G I and Douglas, Gavin M and Cheng, Xi and Rouchka, Eric C and Waigel, Sabine J and Dryden, Gerald W and Alatassi, Houda and Zhang, Huang-Ge and Haribabu, Bodduluri and Vemula, Praveen K and Jala, Venkatakrishna R} } @article {1607, title = {Exome sequencing in families with severe mental illness identifies novel and rare variants in genes implicated in Mendelian neuropsychiatric syndromes.}, journal = {Psychiatry Clin Neurosci}, volume = {73}, year = {2019}, month = {2019 Jan}, pages = {11-19}, abstract = {

AIM: Severe mental illnesses (SMI), such as bipolar disorder and schizophrenia, are highly heritable, and have a complex pattern of inheritance. Genome-wide association studies detect a part of the heritability, which can be attributed to common genetic variation. Examination of rare variants with next-generation sequencing may add to the understanding of the genetic architecture of SMI.

METHODS: We analyzed 32 ill subjects from eight multiplex families and 33 healthy individuals using whole-exome sequencing. Prioritized variants were selected by a three-step filtering process, which included: deleteriousness by five in silico algorithms; sharing within families by affected individuals; rarity in South Asian sample estimated using the Exome Aggregation Consortium data; and complete absence of these variants in control individuals from the same gene pool.

RESULTS: We identified 42 rare, non-synonymous deleterious variants (~5 per pedigree) in this study. None of the variants were shared across families, indicating a {\textquoteright}private{\textquoteright} mutational profile. Twenty (47.6\%) of the variant harboring genes were previously reported to contribute to the risk of diverse neuropsychiatric syndromes, nine (21.4\%) of which were of Mendelian inheritance. These included genes carrying novel deleterious variants, such as the GRM1 gene implicated in spinocerebellar ataxia 44 and the NIPBL gene implicated in Cornelia de Lange syndrome.

CONCLUSION: Next-generation sequencing approaches in family-based studies are useful to identify novel and rare variants in genes for complex disorders like SMI. The findings of the study suggest a potential phenotypic burden of rare variants in Mendelian disease genes, indicating pleiotropic effects in the etiology of SMI.

}, keywords = {Bipolar Disorder, Exome, Female, Genetic Predisposition to Disease, Genetic Variation, Genome-Wide Association Study, Humans, Male, Pedigree, Phenotype, Schizophrenia}, issn = {1440-1819}, doi = {10.1111/pcn.12788}, author = {Ganesh, Suhas and Ahmed P, Husayn and Nadella, Ravi K and More, Ravi P and Seshadri, Manasa and Viswanath, Biju and Rao, Mahendra and Jain, Sanjeev and Mukherjee, Odity} } @article {1601, title = {The Future State of Newborn Stem Cell Banking.}, journal = {J Clin Med}, volume = {8}, year = {2019}, month = {2019 Jan 18}, abstract = {

Newborn stem cell banking began with the establishment of cord blood banks more than 25 years ago. Over the course of nearly three decades, there has been considerable evolution in the clinical application of stem cells isolated from newborn tissues. The industry now finds itself at an inflection point as personalized medicine and regenerative medicine continue to advance. In this review, we summarize our perspective on newborn stem cell banking in the context of the future potential that stem cells from perinatal tissues are likely to play in nascent applications. Specifically, we describe the relevance of newborn stem cell banking and how the cells stored can be utilized as starting material for the next generation of advanced cellular therapies and personalized medicine.

}, issn = {2077-0383}, doi = {10.3390/jcm8010117}, author = {Brown, Katherine S and Rao, Mahendra S and Brown, Heather L} } @article {1602, title = {Generation of a set of isogenic, gene-edited iPSC lines homozygous for all main APOE variants and an APOE knock-out line.}, journal = {Stem Cell Res}, volume = {34}, year = {2019}, month = {2019 Jan}, pages = {101349}, abstract = {

Alzheimer{\textquoteright}s disease (AD) is the most frequent neurodegenerative disease amongst the elderly. The SNPs rs429358 and rs7412 in the APOE gene are the most common risk factor for sporadic AD, and there are three different alleles commonly referred to as APOE-ε2, APOE-ε3 and APOE-ε4. Induced pluripotent stem cells (iPSCs) hold great promise to model AD as such cells can be differentiated in vitro to the required cell type. Here we report the use of CRISPR/Cas9 technology employed on iPSCs from a healthy individual with an APOE-ε3/ε4 genotype to obtain isogenic APOE-ε2/ε2, APOE-ε3/ε3, APOE-ε4/ε4 lines as well as an APOE-knock-out line.

}, issn = {1876-7753}, doi = {10.1016/j.scr.2018.11.010}, author = {Schmid, Benjamin and Prehn, Kennie R and Nimsanor, Natakarn and Garcia, Blanca Irene Aldana and Poulsen, Ulla and J{\o}rring, Ida and Rasmussen, Mikkel A and Clausen, Christian and Mau-Holzmann, Ulrike A and Ramakrishna, Sarayu and Muddashetty, Ravi and Steeg, Rachel and Bruce, Kevin and Mackintosh, Peter and Ebneth, Andreas and Holst, Bj{\o}rn and Cabrera-Socorro, Alfredo} } @article {1609, title = {Generation of two iPSC lines with either a heterozygous V717I or a heterozygous KM670/671NL mutation in the APP gene.}, journal = {Stem Cell Res}, volume = {34}, year = {2019}, month = {2019 Jan}, pages = {101368}, abstract = {

Alzheimer{\textquoteright}s disease (AD) is the most common form of dementia, affecting millions of people worldwide. Mutations in the genes PSEN1, PSEN2 or APP are known to cause familial forms of AD with an early age of onset. In this study, specific pathogenic mutations in the APP gene were introduced into an iPSC line from a healthy individual by the use of CRISPR-Cas9. The study resulted in the generation of two new cell lines, one carrying the V717I APP mutation and one with the KM670/671NL APP mutation.

}, issn = {1876-7753}, doi = {10.1016/j.scr.2018.101368}, author = {Frederiksen, Henriette R and Holst, Bj{\o}rn and Ramakrishna, Sarayu and Muddashetty, Ravi and Schmid, Benjamin and Freude, Kristine} } @article {1608, title = {Graft-implanted, enzyme responsive, tacrolimus-eluting hydrogel enables long-term survival of orthotopic porcine limb vascularized composite allografts: A proof of concept study.}, journal = {PLoS One}, volume = {14}, year = {2019}, month = {2019}, pages = {e0210914}, abstract = {

BACKGROUND: Currently, patients receiving vascularized composite allotransplantation (VCA) grafts must take long-term systemic immunosuppressive therapy to prevent immunologic rejection. The morbidity and mortality associated with these medications is the single greatest barrier to more patients being able to receive these life-enhancing transplants. In contrast to solid organs, VCA, exemplified by hand or face transplants, allow visual diagnosis of clinical acute rejection (AR), directed biopsy and targeted graft therapies. Local immunosuppression in VCA could reduce systemic drug exposure and limit adverse effects. This proof of concept study evaluated, in a large animal forelimb VCA model, the efficacy and tolerability of a novel graft-implanted enzyme-responsive, tacrolimus (TAC)-eluting hydrogel platform, in achieving long-term graft survival.

METHODS: Orthotopic forelimb VCA were performed in single haplotype mismatched mini-swine. Controls (n = 2) received no treatment. Two groups received TAC hydrogel: high dose (n = 4, 91 mg TAC) and low dose (n = 4, 49 mg TAC). The goal was to find a dose that was tolerable and resulted in long-term graft survival. Limbs were evaluated for clinical and histopathological signs of AR. TAC levels were measured in serial blood and skin tissue samples. Tolerability of the dose was evaluated by monitoring animal feeding behavior and weight.

RESULTS: Control limbs underwent Banff Grade IV AR by post-operative day six. Low dose TAC hydrogel treatment resulted in long-term graft survival time to onset of Grade IV AR ranging from 56 days to 93 days. High dose TAC hydrogel also resulted in long-term graft survival (24 to 42 days), but was not well tolerated.

CONCLUSION: Graft-implanted TAC-loaded hydrogel delays the onset of Grade IV AR of mismatched porcine forelimb VCA grafts, resulting in long term graft survival and demonstrates dose-dependent tolerability.

}, issn = {1932-6203}, doi = {10.1371/journal.pone.0210914}, author = {Fries, C Anton and Lawson, Shari D and Wang, Lin C and Slaughter, Kai V and Vemula, Praveen K and Dhayani, Ashish and Joshi, Nitin and Karp, Jeffrey M and Rickard, Rory F and Gorantla, Vijay S and Davis, Michael R} } @article {1613, title = {INDEX-db: The Indian Exome Reference Database (Phase I).}, journal = {J Comput Biol}, volume = {26}, year = {2019}, month = {2019 Mar}, pages = {225-234}, abstract = {

Deep sequencing-based genetic mapping has greatly enhanced the ability to catalog variants with plausible disease association. Confirming how these identified variants contribute to specific disease conditions, across human populations, poses the next challenge. Differential selection pressure may impact the frequency of genetic variations, and thus detection of association with disease conditions, across populations. To understand genotype to phenotype correlations, it thus becomes important to first understand the spectrum of genetic variation within a population by creating a reference map. In this study, we report the development of phase I of a new database of genetic variations called INDian EXome database (INDEX-db), from the Indian population, with an aim to establish a centralized database of integrated information. This could be useful for researchers involved in studying disease mechanisms at clinical, genetic, and cellular levels.

}, issn = {1557-8666}, doi = {10.1089/cmb.2018.0199}, author = {Ahmed P, Husayn and V, Vidhya and More, Ravi Prabhakar and Viswanath, Biju and Jain, Sanjeev and Rao, Mahendra S and Mukherjee, Odity} } @article {1576, title = {KMT1 family methyltransferases regulate heterochromatin-nuclear periphery tethering via histone and non-histone protein methylation.}, journal = {EMBO Rep}, year = {2019}, month = {2019 Mar 11}, abstract = {

Euchromatic histone methyltransferases (EHMTs), members of the KMT1 family, methylate histone and non-histone proteins. Here, we uncover a novel role for EHMTs in regulating heterochromatin anchorage to the nuclear periphery (NP) via non-histone methylation. We show that EHMTs methylate and stabilize LaminB1 (LMNB1), which associates with the H3K9me2-marked peripheral heterochromatin. Loss of LMNB1 methylation or EHMTs abrogates heterochromatin anchorage at the NP We further demonstrate that the loss of EHMTs induces many hallmarks of aging including global reduction of H3K27methyl marks and altered nuclear morphology. Consistent with this, we observe a gradual depletion of EHMTs, which correlates with loss of methylated LMNB1 and peripheral heterochromatin in aging human fibroblasts. Restoration of EHMT expression reverts peripheral heterochromatin defects in aged cells. Collectively, our work elucidates a new mechanism by which EHMTs regulate heterochromatin domain organization and reveals their impact on fundamental changes associated with the intrinsic aging process.

}, issn = {1469-3178}, doi = {10.15252/embr.201643260}, author = {Rao, Radhika Arasala and Ketkar, Alhad Ashok and Kedia, Neelam and Krishnamoorthy, Vignesh K and Lakshmanan, Vairavan and Kumar, Pankaj and Mohanty, Abhishek and Kumar, Shilpa Dilip and Raja, Sufi O and Gulyani, Akash and Chaturvedi, Chandra Prakash and Brand, Marjorie and Palakodeti, Dasaradhi and Rampalli, Shravanti} } @article {1600, title = {Making NSC and Neurons from Patient-Derived Tissue Samples.}, journal = {Methods Mol Biol}, volume = {1919}, year = {2019}, month = {2019}, pages = {9-24}, abstract = {

The human brain and mechanisms underlying its functioning has been a field of intense research due to its complexity, inaccessibility, and the large numbers of debilitating disorders affecting this organ. Model organisms have provided great insight into the functioning of the mammalian brain; however, there exist many features unique to humans which need detailed understanding. In this context, human pluripotent stem cells (HPSCs) have emerged as a promising resource.In the developing brain, cortical diversification is achieved by neural stem cells/neural progenitor cells (NSCs/NPCs) by altering its potency (from multipotent to unipotent) and differentiation capacity (from neurogenesis to gliogenesis). Recent development in tissue reprogramming allows for derivation of NSCs/NPCs from either healthy control subjects manipulated to carry disease mutations or affected individuals carrying specific disease-causing mutations allowing for detailed evaluation of cellular phenotype, pharmacological manipulation, and/or toxicological screening.In this chapter, we will discuss HPSC differentiation into neural stem cells (NSCs) and neurons. We will review the mechanism underlying in vivo neural differentiation and methods which recapitulate this in vitro. We describe a method of deriving NSCs and differentiated mature neurons highlighting key steps of the core protocol. We also provide detailed information of the transcription factor and morphogen map of the developing brain which can be used as a guide to derive region- and lineage-specific NSCs and differentiated neurons.

}, issn = {1940-6029}, doi = {10.1007/978-1-4939-9007-8_2}, author = {Mukherjee, Odity and Acharya, Shubhra and Rao, Mahendra} } @article {1843, title = {Molecular basis for metabolite channeling in a ring opening enzyme of the phenylacetate degradation pathway.}, journal = {Nat Commun}, volume = {10}, year = {2019}, month = {2019 Sep 11}, pages = {4127}, abstract = {

Substrate channeling is a mechanism for the internal transfer of hydrophobic, unstable or toxic intermediates from the active site of one enzyme to another. Such transfer has previously been described to be mediated by a hydrophobic tunnel, the use of electrostatic highways or pivoting and by conformational changes. The enzyme PaaZ is used by many bacteria to degrade environmental pollutants. PaaZ is a bifunctional enzyme that catalyzes the ring opening of oxepin-CoA and converts it to 3-oxo-5,6-dehydrosuberyl-CoA. Here we report the structures of PaaZ determined by electron cryomicroscopy with and without bound ligands. The structures reveal that three domain-swapped dimers of the enzyme form a trilobed structure. A combination of small-angle X-ray scattering (SAXS), computational studies, mutagenesis and microbial growth experiments suggests that the key intermediate is transferred from one active site to the other by a mechanism of electrostatic pivoting of the CoA moiety, mediated by a set of conserved positively charged residues.

}, issn = {2041-1723}, doi = {10.1038/s41467-019-11931-1}, author = {Sathyanarayanan, Nitish and Cannone, Giuseppe and Gakhar, Lokesh and Katagihallimath, Nainesh and Sowdhamini, Ramanathan and Ramaswamy, Subramanian and Vinothkumar, Kutti R} } @article {1644, title = {Myocardin ablation in a cardiac-renal rat model.}, journal = {Sci Rep}, volume = {9}, year = {2019}, month = {2019 Apr 10}, pages = {5872}, abstract = {

Cardiorenal syndrome is defined by primary heart failure conditions influencing or leading to renal injury or dysfunction. Dilated cardiomyopathy (DCM) is a major co-existing form of heart failure (HF) with renal diseases. Myocardin (MYOCD), a cardiac-specific co-activator of serum response factor (SRF), is increased in DCM porcine and patient cardiac tissues and plays a crucial role in the pathophysiology of DCM. Inhibiting the increased MYOCD has shown to be partially rescuing the DCM phenotype in porcine model. However, expression levels of MYOCD in the cardiac tissues of the cardiorenal syndromic patients and the effect of inhibiting MYOCD in a cardiorenal syndrome model remains to be explored. Here, we analyzed the expression levels of MYOCD in the DCM patients with and without renal diseases. We also explored, whether cardiac specific silencing of MYOCD expression could ameliorate the cardiac remodeling and improve cardiac function in a renal artery ligated rat model (RAL). We observed an increase in MYOCD levels in the endomyocardial biopsies of DCM patients associated with renal failure compared to DCM alone. Silencing of MYOCD in RAL rats by a cardiac homing peptide conjugated MYOCD siRNA resulted in attenuation of cardiac hypertrophy, fibrosis and restoration of the left ventricular functions. Our data suggest hyper-activation of MYOCD in the pathogenesis of the cardiorenal failure cases. Also, MYOCD silencing showed beneficial effects by rescuing cardiac hypertrophy, fibrosis, size and function in a cardiorenal rat model.

}, issn = {2045-2322}, doi = {10.1038/s41598-019-42009-z}, author = {Mittal, Anupam and Rana, Santanu and Sharma, Rajni and Kumar, Akhilesh and Prasad, Rishikesh and Raut, Satish K and Sarkar, Sagartirtha and Saikia, Uma Nahar and Bahl, Ajay and Dhandapany, Perundurai S and Khullar, Madhu} } @article {1744, title = {NMDAR mediated translation at the synapse is regulated by MOV10 and FMRP.}, journal = {Mol Brain}, volume = {12}, year = {2019}, month = {2019 Jul 10}, pages = {65}, abstract = {

Protein synthesis is crucial for maintaining synaptic plasticity and synaptic signalling. Here we have attempted to understand the role of RNA binding proteins, Fragile X Mental Retardation Protein (FMRP) and Moloney Leukemia Virus 10 (MOV10) protein in N-Methyl-D-Aspartate Receptor (NMDAR) mediated translation regulation. We show that FMRP is required for translation downstream of NMDAR stimulation and MOV10 is the key specificity factor in this process. In rat cortical synaptoneurosomes, MOV10 in association with FMRP and Argonaute 2 (AGO2) forms the inhibitory complex on a subset of NMDAR responsive mRNAs. On NMDAR stimulation, MOV10 dissociates from AGO2 and promotes the translation of its target mRNAs. FMRP is required to form MOV10-AGO2 inhibitory complex and to promote translation of MOV10 associated mRNAs. Phosphorylation of FMRP appears to be the potential switch for NMDAR mediated translation and in the absence of FMRP, the distinct translation response to NMDAR\ stimulation is lost. Thus, FMRP and MOV10 have an important regulatory role in NMDAR mediated translation at the synapse.

}, issn = {1756-6606}, doi = {10.1186/s13041-019-0473-0}, author = {Kute, Preeti Madhav and Ramakrishna, Sarayu and Neelagandan, Nagammal and Chattarji, Sumantra and Muddashetty, Ravi S} } @article {1989, title = {Secretion of leukotrienes by senescent lung fibroblasts promotes pulmonary fibrosis.}, journal = {JCI Insight}, volume = {4}, year = {2019}, month = {2019 Dec 19}, abstract = {

Accumulation of senescent cells is associated with the progression of pulmonary fibrosis, but mechanisms accounting for this linkage are not well understood. To explore this issue, we investigated whether a class of biologically active profibrotic lipids, the leukotrienes (LT), is part of the senescence-associated secretory phenotype. The analysis of conditioned medium (CM), lipid extracts, and gene expression of LT biosynthesis enzymes revealed that senescent cells secreted LT, regardless of the origin of the cells or the modality of senescence induction. The synthesis of LT was biphasic and followed by antifibrotic prostaglandin (PG) secretion. The LT-rich CM of senescent lung fibroblasts (IMR-90) induced profibrotic signaling in naive fibroblasts, which were abrogated by inhibitors of ALOX5, the principal enzyme in LT biosynthesis. The bleomycin-induced expression of genes encoding LT and PG synthases, level of cysteinyl LT in the bronchoalveolar lavage, and overall fibrosis were reduced upon senescent cell removal either in a genetic mouse model or after senolytic treatment. Quantification of ALOX5+ cells in lung explants obtained from idiopathic pulmonary fibrosis (IPF) patients indicated that half of these cells were also senescent (p16Ink4a+). Unlike human fibroblasts from unused donor lungs made senescent by irradiation, senescent IPF fibroblasts secreted LTs but failed to synthesize PGs. This study demonstrates for the first time to our knowledge that senescent cells secrete functional LTs, significantly contributing to the LT pool known to cause or exacerbate IPF.

}, issn = {2379-3708}, doi = {10.1172/jci.insight.130056}, author = {Wiley, Christopher D and Brumwell, Alexis N and Davis, Sonnet S and Jackson, Julia R and Valdovinos, Alexis and Calhoun, Cheresa and Alimirah, Fatouma and Castellanos, Carlos A and Ruan, Richard and Wei, Ying and Chapman, Harold A and Ramanathan, Arvind and Campisi, Judith and Jourdan Le Saux, Claude} } @article {1844, title = {Serotonin is essential for eye regeneration in planaria Schmidtea mediterranea.}, journal = {FEBS Lett}, year = {2019}, month = {2019 Sep 17}, abstract = {

Planaria is an ideal system to study factors involved in regeneration and tissue homeostasis. Little is known about the role of metabolites and small molecules in stem cell maintenance and lineage specification in planarians. Using liquid chromatography and mass spectrometry (LC-MS)-based quantitative metabolomics, we determined the relative levels of metabolites in stem cells, progenitors, and differentiated cells of the planarian Schmidtea mediterranea. Tryptophan and its metabolic product serotonin are significantly enriched in stem cells and progenitor population. Serotonin biosynthesis in these cells is brought about by a non-canonical enzyme, phenylalanine hydroxylase (PAH). Knockdown of Smed-pah leads to complete disappearance of eyes in regenerating planaria, while exogenous supply of serotonin and its precursor rescue the eyeless phenotype. Our results demonstrate a key role for serotonin in eye regeneration.

}, issn = {1873-3468}, doi = {10.1002/1873-3468.13607}, author = {Sarkar, Arunabha and Mukundan, Namita and Sowndarya, Sai and Dubey, Vinay Kumar and Babu, Rosana and Lakshmanan, Vairavan and Rangiah, Kannan and Panicker, Mitradas M and Palakodeti, Dasaradhi and Subramanian, Sabarinath Peruvemba and Ramaswamy, Subramanian} } @article {1986, title = {Sustained Secretion of the Antimicrobial Peptide S100A7 Is Dependent on the Downregulation of Caspase-8.}, journal = {Cell Rep}, volume = {29}, year = {2019}, month = {2019 Nov 26}, pages = {2546-2555.e4}, abstract = {

Antimicrobial peptides (AMPs) are the body{\textquoteright}s natural innate immune defense against a spectrum of pathogens and can also modulate cell proliferation, chemotaxis, angiogenesis, wound healing, and immune cell activity. Harnessing these diverse functions for prophylactic use is contingent upon understanding the regulatory mechanisms governing their unconventional secretion from cells. Analysis of the secretion of S100A7 (Psoriasin), an abundant AMP stored in differentiated keratinocytes of the skin, has revealed an unexpected biphasic secretory response to bacterial exposure. The core components regulating S100A7 secretion are NFκB/p38MAPK, caspase-1, and interleukin (IL)-1α. The initial activation of this core machinery is mediated by Toll-like receptor signaling, whereas the chronic response is mediated by Caspase-8 downregulation. Interestingly, there is a concomitant downregulation of Caspase-8 in inflammatory skin diseases wherein S100A7 is constitutively released. These results highlight the potential of targeting these components to control the release of AMPs from the skin in both homeostatic and disease conditions.

}, issn = {2211-1247}, doi = {10.1016/j.celrep.2019.10.090}, author = {Bhatt, Tanay and Bhosale, Aishwarya and Bajantri, Bhavya and Mathapathi, Mruthyunjaya Swamy and Rizvi, Abrar and Scita, Giorgio and Majumdar, Amitabha and Jamora, Colin} } @article {1959, title = {Sustained Secretion of the Antimicrobial Peptide S100A7 Is Dependent on the Downregulation of Caspase-8.}, year = {2019}, month = {09/2019}, abstract = {

Antimicrobial peptides (AMPs) are the body{\textquoteright}s natural innate immune defense against a spectrum of pathogens and can also modulate cell proliferation, chemotaxis, angiogenesis, wound healing, and immune cell activity. Harnessing these diverse functions for prophylactic use is contingent upon understanding the regulatory mechanisms governing their unconventional secretion from cells. Analysis of the secretion of S100A7 (Psoriasin), an abundant AMP stored in differentiated keratinocytes of the skin, has revealed an unexpected biphasic secretory response to bacterial exposure. The core components regulating S100A7 secretion are NFκB/p38MAPK, caspase-1, and interleukin (IL)-1α. The initial activation of this core machinery is mediated by Toll-like receptor signaling, whereas the chronic response is mediated by Caspase-8 downregulation. Interestingly, there is a concomitant downregulation of Caspase-8 in inflammatory skin diseases wherein S100A7 is constitutively released. These results highlight the potential of targeting these components to control the release of AMPs from the skin in both homeostatic and disease conditions.

Copyright {\textcopyright} 2019 The Author(s). Published by Elsevier Inc. All rights reserved.

}, author = {Bhatt,T and Bhosale,A and Bajantri,B and Mathapathi,MS and Rizvi,A and Scita,G and Majumdar,A and Jamora,C} } @article {1743, title = {A tRNA modification balances carbon and nitrogen metabolism by regulating phosphate homeostasis.}, journal = {Elife}, volume = {8}, year = {2019}, month = {2019 Jul 01}, abstract = {

Cells must appropriately sense and integrate multiple metabolic resources to commit to proliferation. Here, we report that cells regulate carbon and nitrogen metabolic homeostasis through tRNA U-thiolation. Despite amino acid sufficiency, tRNA-thiolation deficient cells appear amino acid starved. In these cells, carbon flux towards nucleotide synthesis decreases, and trehalose synthesis increases, resulting in a starvation-like metabolic signature. Thiolation mutants have only minor translation defects. However, in these cells phosphate homeostasis genes are strongly down-regulated, resulting in an effectively phosphate-limited state. Reduced phosphate enforces a metabolic switch, where glucose-6-phosphate is routed towards storage carbohydrates. Notably, trehalose synthesis, which releases phosphate and thereby restores phosphate availability, is central to this metabolic rewiring. Thus, cells use thiolated tRNAs to perceive amino acid sufficiency, balance carbon and amino acid metabolic flux and grow optimally, by controlling phosphate availability. These results further biochemically explain how phosphate availability determines a switch to a {\textquoteright}starvation-state{\textquoteright}.

}, issn = {2050-084X}, doi = {10.7554/eLife.44795}, author = {Gupta, Ritu and Walvekar, Adhish and Liang, Shun and Rashida, Zeenat and Shah, Premal and Laxman, Sunil} } @article {1736, title = {Unraveling the ECM-Immune Cell Crosstalk in Skin Diseases.}, journal = {Front Cell Dev Biol}, volume = {7}, year = {2019}, month = {2019}, pages = {68}, abstract = {

The extracellular matrix (ECM) is a complex network of proteins and proteoglycans secreted by keratinocytes, fibroblasts and immune cells. The function of the skin ECM has expanded from being a scaffold that provides structural integrity, to a more dynamic entity that is constantly remodeled to maintain tissue homeostasis. The ECM functions as ligands for cell surface receptors such as integrins, dystroglycans, and toll-like receptors (TLRs) and regulate cellular signaling and immune cell dynamics. The ECM also acts as a sink for growth factors and cytokines, providing critical cues during epithelial morphogenesis. Dysregulation in the organization and deposition of ECMs lead to a plethora of pathophysiological conditions that are exacerbated by aberrant ECM-immune cell interactions. In this review, we focus on the interplay between ECM and immune cells in the context of skin diseases and also discuss state of the art therapies that target the key molecular players involved.

}, issn = {2296-634X}, doi = {10.3389/fcell.2019.00068}, author = {Bhattacharjee, Oindrila and Ayyangar, Uttkarsh and Kurbet, Ambika S and Ashok, Driti and Raghavan, Srikala} } @article {1582, title = {Urolithin A, a Novel Natural Compound to Target PI3K/AKT/mTOR Pathway in Pancreatic Cancer.}, journal = {Mol Cancer Ther}, volume = {18}, year = {2019}, month = {2019 Feb}, pages = {301-311}, abstract = {

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignancy and is highly resistant to standard treatment regimens. Targeted therapies against , a mutation present in an overwhelming majority of PDAC cases, have been largely ineffective. However, inhibition of downstream components in the KRAS signaling cascade provides promising therapeutic targets in the management of PDAC and warrants further exploration. Here, we investigated Urolithin A (Uro A), a novel natural compound derived from pomegranates, which targets numerous kinases downstream of KRAS, in particular the PI3K/AKT/mTOR signaling pathways. We showed that treatment of PDAC cells with Uro A blocked the phosphorylation of AKT and p70S6K successfully inhibited the growth of tumor xenografts, and increased overall survival of Ptf1a;LSL-Kras;Tgfbr2 (PKT) mice compared with vehicle or gemcitabine therapy alone. Histologic evaluation of these Uro A-treated tumor samples confirmed mechanistic actions of Uro A via decreased phosphorylation of AKT and p70S6K, reduced proliferation, and increased cellular apoptosis in both xenograft and PKT mouse models. In addition, Uro A treatment reprogrammed the tumor microenvironment, as evidenced by reduced levels of infiltrating immunosuppressive cell populations such as myeloid-derived suppressor cells, tumor-associated macrophages, and regulatory T cells. Overall, this work provides convincing preclinical evidence for the utility of Uro A as a therapeutic agent in PDAC through suppression of the PI3K/AKT/mTOR pathway.

}, issn = {1538-8514}, doi = {10.1158/1535-7163.MCT-18-0464}, author = {Totiger, Tulasigeri M and Srinivasan, Supriya and Jala, Venkatakrishna R and Lamichhane, Purushottam and Dosch, Austin R and Gaidarski, Alexander A and Joshi, Chandrashekhar and Rangappa, Shobith and Castellanos, Jason and Vemula, Praveen Kumar and Chen, Xi and Kwon, Deukwoo and Kashikar, Nilesh and VanSaun, Michael and Merchant, Nipun B and Nagathihalli, Nagaraj S} } @article {1192, title = {Automation aided optimization of cloning, expression and purification of enzymes of the bacterial sialic acid catabolic and sialylation pathways enzymes for structural studies.}, journal = {Microb Biotechnol}, volume = {11}, year = {2018}, month = {2018 Mar}, pages = {420-428}, abstract = {

The process of obtaining a well-expressing, soluble and correctly folded constructs can be made easier and quicker by automating the optimization of cloning, expression and purification. While there are many semiautomated pipelines available for cloning, expression and purification, there is hardly any pipeline that involves complete automation. Here, we achieve complete automation of all the steps involved in cloning and in\ vivo expression screening. This is demonstrated using 18 genes involved in sialic acid catabolism and the surface sialylation pathway. Our main objective was to clone these genes into a His-tagged Gateway vector, followed by their small-scale expression optimization in\ vivo. The constructs that showed best soluble expression were then selected for purification studies and scaled up for crystallization studies. Our technique allowed us to quickly find conditions for producing significant quantities of soluble proteins in Escherichia coli, their large-scale purification and successful crystallization of a number of these proteins. The method can be implemented in other cases where one needs to screen a large number of constructs, clones and expression vectors for successful recombinant production of functional proteins.

}, issn = {1751-7915}, doi = {10.1111/1751-7915.13041}, author = {Bairy, Sneha and Gopalan, Lakshmi Narayanan and Setty, Thanuja Gangi and Srinivasachari, Sathya and Manjunath, Lavanyaa and Kumar, Jay Prakash and Guntupalli, Sai R and Bose, Sucharita and Nayak, Vinod and Ghosh, Swagatha and Sathyanarayanan, Nitish and Caing-Carlsson, Rhawnie and Wahlgren, Weixiao Yuan and Friemann, Rosmarie and Ramaswamy, S and Neerathilingam, Muniasamy} } @article {1587, title = {Bioresponsive drug delivery systems in intestinal inflammation: State-of-the-art and future perspectives.}, journal = {Adv Drug Deliv Rev}, year = {2018}, month = {2018 Jun 29}, abstract = {

Oral colon-specific delivery systems emerged as the main therapeutic cargos by making a significant impact in the field of modern medicine for local drug delivery in intestinal inflammation. The site-specific delivery of therapeutics (aminosalicylates, glucocorticoids, biologics) to the ulcerative mucus tissue can provide prominent advantages in mucosal healing (MH). Attaining gut mucosal healing and anti-fibrosis are main treatment outcomes in inflammatory bowel disease (IBD). The pharmaceutical strategies that are commonly used to achieve a colon-specific drug delivery system include time, pH-dependent polymer coating, prodrug, colonic microbiota-activated delivery systems and a combination of these approaches. Amongst the different approaches reported, the use of biodegradable polysaccharide coated systems holds great promise in delivering drugs to the ulcerative regions. The present review focuses on major physiological gastro-intestinal tract challenges involved in altering the pharmacokinetics of delivery systems, pathophysiology of MH and fibrosis, reported drug-polysaccharide cargos and focusing on conventional to advanced disease responsive delivery strategies, highlighting their limitations and future perspectives in intestinal inflammation therapy.

}, issn = {1872-8294}, doi = {10.1016/j.addr.2018.06.021}, author = {Kotla, Niranjan G and Rana, Shubhasmin and Sivaraman, Gandhi and Sunnapu, Omprakash and Vemula, Praveen K and Pandit, Abhay and Rochev, Yury} } @article {1597, title = {Crystal structures and kinetics of N-acetylneuraminate lyase from Fusobacterium nucleatum.}, journal = {Acta Crystallogr F Struct Biol Commun}, volume = {74}, year = {2018}, month = {2018 Nov 01}, pages = {725-732}, abstract = {

N-Acetyl-D-neuraminic acid lyase (NanA) catalyzes the breakdown of sialic acid (Neu5Ac) to N-acetyl-D-mannosamine (ManNAc) and pyruvate. NanA plays a key role in Neu5Ac catabolism in many pathogenic and bacterial commensals where sialic acid is available as a carbon and nitrogen source. Several pathogens or commensals decorate their surfaces with sialic acids as a strategy to escape host innate immunity. Catabolism of sialic acid is key to a range of host-pathogen interactions. In this study, atomic resolution structures of NanA from Fusobacterium nucleatum (FnNanA) in ligand-free and ligand-bound forms are reported at 2.32 and 1.76 {\r A} resolution, respectively. F. nucleatum is a Gram-negative pathogen that causes gingival and periodontal diseases in human hosts. Like other bacterial N-acetylneuraminate lyases, FnNanA also shares the triosephosphate isomerase (TIM)-barrel fold. As observed in other homologous enzymes, FnNanA forms a tetramer. In order to characterize the structure-function relationship, the steady-state kinetic parameters of the enzyme are also reported.

}, keywords = {Bacterial Proteins, Crystallography, X-Ray, Fusobacterium nucleatum, Hydrogen Bonding, Models, Molecular, N-Acetylneuraminic Acid, Oxo-Acid-Lyases, Protein Conformation, Protein Folding, Pyruvic Acid, Schiff Bases, Sequence Alignment, Tyrosine}, issn = {2053-230X}, doi = {10.1107/S2053230X18012992}, author = {Kumar, Jay Prakash and Rao, Harshvardhan and Nayak, Vinod and Ramaswamy, S} } @article {1184, title = {Decreased expression of cell adhesion genes in cancer stem-like cells isolated from primary oral squamous cell carcinomas.}, journal = {Tumour Biol}, volume = {40}, year = {2018}, month = {2018 May}, pages = {1010428318780859}, abstract = {

The goal of this study was to isolate cancer stem-like cells marked by high expression of CD44, a putative cancer stem cell marker, from primary oral squamous cell carcinomas and identify distinctive gene expression patterns in these cells. From 1 October 2013 to 4 September 2015, 76 stage III-IV primary oral squamous cell carcinoma of the gingivobuccal sulcus were resected. In all, 13 tumours were analysed by immunohistochemistry to visualise CD44-expressing cells. Expression of CD44 within The Cancer Genome Atlas-Head and Neck Squamous Cell Carcinoma RNA-sequencing data was also assessed. Seventy resected tumours were dissociated into single cells and stained with antibodies to CD44 as well as CD45 and CD31 (together referred as Lineage/Lin). From 45 of these, CD44Lin and CD44Lin subpopulations were successfully isolated using fluorescence-activated cell sorting, and good-quality RNA was obtained from 14 such sorted pairs. Libraries from five pairs were sequenced and the results analysed using bioinformatics tools. Reverse transcription quantitative polymerase chain reaction was performed to experimentally validate the differential expression of selected candidate genes identified from the transcriptome sequencing in the same 5 and an additional 9 tumours. CD44 was expressed on the surface of poorly differentiated tumour cells, and within the The Cancer Genome Atlas-Head and Neck Squamous Cell Carcinoma samples, its messenger RNA levels were higher in tumours compared to normal. Transcriptomics revealed that 102 genes were upregulated and 85 genes were downregulated in CD44Lin compared to CD44Lin cells in at least 3 of the 5 tumours sequenced. The upregulated genes included those involved in immune regulation, while the downregulated genes were enriched for genes involved in cell adhesion. Decreased expression of PCDH18, MGP, SPARCL1 and KRTDAP was confirmed by reverse transcription quantitative polymerase chain reaction. Lower expression of the cell-cell adhesion molecule PCDH18 correlated with poorer overall survival in the The Cancer Genome Atlas-Head and Neck Squamous Cell Carcinoma data highlighting it as a potential negative prognostic factor in this cancer.

}, issn = {1423-0380}, doi = {10.1177/1010428318780859}, author = {Mishra, Amrendra and Sriram, Harshini and Chandarana, Pinal and Tanavde, Vivek and Kumar, Rekha V and Gopinath, Ashok and Govindarajan, Raman and Ramaswamy, S and Sadasivam, Subhashini} } @article {1579, title = {Developing two reference control samples for the Indian population.}, journal = {Stem Cell Res}, volume = {30}, year = {2018}, month = {2018 07}, pages = {38-42}, abstract = {

Human induced Pluripotent Stem Cells (HiPSCs) have immense potential in research and therapeutics. Under the aegis of Department of Biotechnology funded national program entitled, "The Accelerator program for Discovery in Brain Disorders using Stem Cells (ADBS)" we have established a HiPSC biorepository (https://www.ncbs.res.in/adbs/bio-repository) with an objective to study severe mental illness. The repository comprises of HiPSC lines derived from healthy control donors and individuals with life time diagnosis of severe mental illness from dense families. In the current report we submit information regarding two population control reference lines (male = 1; female = 1) from this biorepository.

}, keywords = {Cell Differentiation, Humans, India, Induced Pluripotent Stem Cells}, issn = {1876-7753}, doi = {10.1016/j.scr.2018.05.001}, author = {Iyer, Shruti and Bhatia, Priyanka and Rao, Mahendra and Mukherjee, Odity} } @article {1149, title = {Discovery biology of neuropsychiatric syndromes (DBNS): a center for integrating clinical medicine and basic science.}, journal = {BMC Psychiatry}, volume = {18}, year = {2018}, month = {2018 Apr 18}, pages = {106}, abstract = {

BACKGROUND: There is emerging evidence that there are shared genetic, environmental and developmental risk factors in psychiatry, that cut across traditional diagnostic boundaries. With this background, the Discovery biology of neuropsychiatric syndromes (DBNS) proposes to recruit patients from five different syndromes (schizophrenia, bipolar disorder, obsessive compulsive disorder, Alzheimer{\textquoteright}s dementia and substance use disorders), identify those with multiple affected relatives, and invite these families to participate in this study. The families will be assessed: 1) To compare neuro-endophenotype measures between patients, first degree relatives (FDR) and healthy controls., 2) To identify cellular phenotypes which differentiate the groups., 3) To examine the longitudinal course of neuro-endophenotype measures., 4) To identify measures which correlate with outcome, and 5) To create a unified digital database and biorepository.

METHODS: The identification of the index participants will occur at well-established specialty clinics. The selected individuals will have a strong family history (with at least another affected FDR) of mental illness. We will also recruit healthy controls without family history of such illness. All recruited individuals (N = 4500) will undergo brief clinical assessments and a blood sample will be drawn for isolation of DNA and peripheral blood mononuclear cells (PBMCs). From among this set, a subset of 1500 individuals (300 families and 300 controls) will be assessed on several additional assessments [detailed clinical assessments, endophenotype measures (neuroimaging- structural and functional, neuropsychology, psychophysics-electroencephalography, functional near infrared spectroscopy, eye movement tracking)], with the intention of conducting repeated measurements every alternate year. PBMCs from this set will be used to generate lymphoblastoid cell lines, and a subset of these would be converted to induced pluripotent stem cell lines and also undergo whole exome sequencing.

DISCUSSION: We hope to identify unique and overlapping brain endophenotypes for major psychiatric syndromes. In a proportion of subjects, we expect these neuro-endophenotypes to progress over time and to predict treatment outcome. Similarly, cellular assays could differentiate cell lines derived from such groups. The repository of biomaterials as well as digital datasets of clinical parameters, will serve as a valuable resource for the broader scientific community who wish to address research questions in the area.

}, issn = {1471-244X}, doi = {10.1186/s12888-018-1674-2}, author = {Viswanath, Biju and Rao, Naren P and Narayanaswamy, Janardhanan C and Sivakumar, Palanimuthu T and Kandasamy, Arun and Kesavan, Muralidharan and Mehta, Urvakhsh Meherwan and Venkatasubramanian, Ganesan and John, John P and Mukherjee, Odity and Purushottam, Meera and Kannan, Ramakrishnan and Mehta, Bhupesh and Kandavel, Thennarasu and Binukumar, B and Saini, Jitender and Jayarajan, Deepak and Shyamsundar, A and Moirangthem, Sydney and Vijay Kumar, K G and Thirthalli, Jagadisha and Chandra, Prabha S and Gangadhar, Bangalore N and Murthy, Pratima and Panicker, Mitradas M and Bhalla, Upinder S and Chattarji, Sumantra and Benegal, Vivek and Varghese, Mathew and Reddy, Janardhan Y C and Raghu, Padinjat and Rao, Mahendra and Jain, Sanjeev} } @article {1188, title = {Exploring membrane permeability of Tomatidine to enhance lipid mediated nucleic acid transfections}, journal = {Biochimica et Biophysica Acta (BBA) - Biomembranes}, year = {2018}, pages = {-}, abstract = {

Abstract Intracellular delivery of nucleic acids is one of the critical steps in the transfections. Prior findings demonstrated various strategies including membrane fusion, endosomal escape for the efficient cytoplasmic delivery. In our continuing efforts to improve the nucleic acids transfections, we harnessed cell permeable properties of Tomatidine (T), a steroidal alkaloid abundantly found in green tomatoes for maximizing intracellular delivery of lipoplexes. We doped Tomatidine into liposomes of cationic lipid with amide linker (A) from our lipid library. Six liposomal formulations (AT) of Lipid A (1 mM) with varying concentrations of Tomatidine (0{\textendash}1 mM) were prepared and evaluated for their transfection efficacies. Owing to its signature characteristic of cell membrane permeability, Tomatidine modulated endocytosis process, enhanced the intracellular delivery of the lipoplexes, and in turn increased the transfection efficacy of cationic liposomes. Our findings provide {\textquoteleft}proof of concept{\textquoteright} for enhancing transfections in gene delivery applications with Tomatidine in cationic liposomal formulations. These findings can be further applied in lipid mediated gene therapy and drug delivery applications.

}, keywords = {Endocytosis}, issn = {0005-2736}, doi = {https://doi.org/10.1016/j.bbamem.2018.06.006}, url = {https://www.sciencedirect.com/science/article/pii/S0005273618301780}, author = {Vignesh K. Rangasami and Brijesh Lohchania and Chandrashekhar Voshavar and Harikrishna R. Rachamalla and Rajkumar Banerjee and Ashish Dhayani and Saravanabhavan Thangavel and Praveen K. Vemula and Srujan Marepally} } @article {1584, title = {Extinction recall of fear memories formed before stress is not affected despite higher theta activity in the amygdala.}, journal = {Elife}, volume = {7}, year = {2018}, month = {2018 08 13}, abstract = {

Stress is known to exert its detrimental effects not only by enhancing fear, but also by impairing its extinction. However, in earlier studies stress exposure preceded both processes. Thus, compared to unstressed animals, stressed animals had to extinguish fear memories that were strengthened by prior exposure to stress. Here, we dissociate the two processes to examine if stress specifically impairs the acquisition and recall of fear extinction. Strikingly, when fear memories were formed before stress exposure, thereby allowing animals to initiate extinction from comparable levels of fear, recall of fear extinction was unaffected. Despite this, we observed a persistent increase in theta activity in the BLA. Theta activity in the mPFC, by contrast, was normal. Stress also disrupted mPFC-BLA theta-frequency synchrony and directional coupling. Thus, in the absence of the fear-enhancing effects of stress, the expression of fear during and after extinction reflects normal regulation of theta activity in the mPFC, not theta hyperactivity in the amygdala.

}, keywords = {Amygdala, Animals, Extinction, Psychological, Fear, Male, Memory, Mental Recall, Prefrontal Cortex, Rats, Sprague-Dawley, Stress, Physiological, Theta Rhythm}, issn = {2050-084X}, doi = {10.7554/eLife.35450}, author = {Rahman, Mohammed Mostafizur and Shukla, Ashutosh and Chattarji, Sumantra} } @article {1598, title = {FMRP Interacts with C/D Box snoRNA in the Nucleus and Regulates Ribosomal RNA Methylation.}, journal = {iScience}, volume = {9}, year = {2018}, month = {2018 Nov 30}, pages = {399-411}, abstract = {

FMRP is an RNA-binding protein that is known to localize in the cytoplasm and in the nucleus. Here, we have identified an interaction of FMRP with a specific set of C/D box snoRNAs in the nucleus. C/D box snoRNAs guide 2{\textquoteright}O methylations of ribosomal RNA (rRNA) on defined sites, and this modification regulates rRNA folding and assembly of ribosomes. 2{\textquoteright}O methylation of rRNA is partial on several sites in human embryonic stem cells, which results in ribosomes with differential methylation patterns. FMRP-snoRNA interaction affects rRNA methylation on several of these sites, and in the absence of FMRP, differential methylation pattern of rRNA is significantly altered. We found that FMRP recognizes ribosomes carrying specific methylation patterns on rRNA and the recognition of methylation pattern by FMRP may potentially determine the translation status of its target mRNAs. Thus, FMRP integrates its function in the nucleus and in the cytoplasm.

}, issn = {2589-0042}, doi = {10.1016/j.isci.2018.11.007}, author = {D{\textquoteright}Souza, Michelle Ninochka and Gowda, Naveen Kumar Chandappa and Tiwari, Vishal and Babu, Rosana Ottakandathil and Anand, Praveen and Dastidar, Sudhriti Ghosh and Singh, Randhir and James, Owen G and Selvaraj, Bhuvaneish and Pal, Rakhi and Ramesh, Arati and Chattarji, Sumantra and Chandran, Siddharthan and Gulyani, Akash and Palakodeti, Dasaradhi and Muddashetty, Ravi S} } @article {1145, title = {Induction of quiescence (G0) in bone marrow stromal stem cells enhances their stem cell characteristics.}, journal = {Stem Cell Res}, volume = {30}, year = {2018}, month = {2018 May 17}, pages = {69-80}, abstract = {

Several studies have suggested that bone marrow stromal steam cells (BMSC) exist in a quiescent state (G0) within the in vivo niche; however, an explicit analysis of the biology of G0 state-BMSC has not been reported. We hypothesized that induction of G0 in BMSC might enhance their stem cell properties. Thus, we induced quiescence in BMSC in vitro by (a) suspension culture in a viscous medium or (b) culture on soft polyacrylamide substrate; and examined their molecular and functional phenotype. Induction of G0 was confirmed by bromo-deoxyuridine (BrdU) labelling and analysis of cell cycle gene expression. Upon reactivation and re-entry into cell cycle, G0 state-BMSC exhibited enhanced clonogenic self-renewal, preferential differentiation into osteoblastic rather than adipocytic cells and increased ectopic bone formation when implanted subcutaneously in vivo in immune-deficient mice, compared to asynchronous proliferating (pre-G0) BMSC. Global gene expression profiling revealed reprogramming of the transcriptome during G0 state including significant alterations in relevant pathways and expression of secreted factors, suggesting altered autocrine and paracrine signaling by G0 state-BMSC and a possible mechanism for enhanced bone formation. G0 state-BMSC might provide a clinically relevant model for understanding the in vivo biology of BMSC.

}, issn = {1876-7753}, doi = {10.1016/j.scr.2018.05.010}, author = {Rumman, Mohammad and Majumder, Abhijit and Harkness, Linda and Venugopal, Balu and Vinay, M B and Pillai, Malini S and Kassem, Moustapha and Dhawan, Jyotsna} } @article {1581, title = {Infectivity of adeno-associated virus serotypes in mouse testis.}, journal = {BMC Biotechnol}, volume = {18}, year = {2018}, month = {2018 Nov 01}, pages = {70}, abstract = {

BACKGROUND: Recombinant adeno-associated viruses (AAVs) are emerging as favoured transgene delivery vectors for both research applications and gene therapy. In this context, a thorough investigation of the potential of various AAV serotypes to transduce specific cell types is valuable. Here, we rigorously tested the infectivity of a number of AAV serotypes in murine testis by direct testicular injection.

RESULTS: We report the tropism of serotypes AAV2, 5, 8, 9 and AAVrh10 in mouse testis. We reveal unique infectivity of AAV2 and AAV9, which preferentially target intertubular testosterone-producing Leydig cells. Remarkably, AAV2 TM, a mutant for capsid designed to increase transduction, displayed a dramatic alteration in tropism; it infiltrated seminiferous tubules unlike wildtype AAV2 and transduced Sertoli cells. However, none of the AAVs tested infected spermatogonial cells.

CONCLUSIONS: In spite of direct testicular injection, none of the tested AAVs appeared to infect sperm progenitors as assayed by reporter expression. This lends support to the current view that AAVs are safe gene-therapy vehicles. However, testing the presence of rAAV genomic DNA in germ cells is necessary to assess the risk of individual serotypes.

}, issn = {1472-6750}, doi = {10.1186/s12896-018-0479-1}, author = {Rajasekaran, Santhanasabapathy and Thatte, Jayashree and Periasamy, Jayaprakash and Javali, Alok and Jayaram, Manjunath and Sen, Dwaipayan and Krishnagopal, Akshaya and Jayandharan, Giridhara R and Sambasivan, Ramkumar} } @article {1148, title = {Isolating Immune Cells from Mouse Embryonic Skin.}, journal = {Methods Mol Biol}, year = {2018}, month = {2018 May 24}, abstract = {

Skin is the primary barrier against the external environment and develops a robust immune network for its surveillance. The origin of the resident immune cells of the skin has become a focus of interest over past a decade. Fate mapping studies have revealed that the macrophages home into the skin as early as E12.5 and are derived from the yolk sac and fetal liver. The resident γδT cells are born in the thymus and home to the skin by E16.5. Recent work from our lab has shown that the embryonic macrophages can actively remodel the extracellular matrix in skin suggesting that the skin immune system can be activated long before exposure to foreign antigens. In this chapter, we present a detailed protocol for isolating monocytes, macrophages, and epidermal dendritic T cell populations from embryonic skin.

}, issn = {1940-6029}, doi = {10.1007/7651_2018_148}, author = {Kurbet, Ambika S and Raghavan, Srikala} } @article {1155, title = {"Just a spoonful of sugar...": import of sialic acid across bacterial cell membranes.}, journal = {Biophys Rev}, volume = {10}, year = {2018}, month = {2018 Apr}, pages = {219-227}, abstract = {

Eukaryotic cell surfaces are decorated with a complex array of glycoconjugates that are usually capped with sialic acids, a large family of over 50 structurally distinct nine-carbon amino sugars, the most common member of which is N-acetylneuraminic acid. Once made available through the action of neuraminidases, bacterial pathogens and commensals utilise host-derived sialic acid by degrading it for energy or repurposing the sialic acid onto their own cell surface to camouflage the bacterium from the immune system. A functional sialic acid transporter has been shown to be essential for the uptake of sialic acid in a range of human bacterial pathogens and important for host colonisation and persistence. Here, we review the state-of-play in the field with respect to the molecular mechanisms by which these bio-nanomachines transport sialic acids across bacterial cell membranes.

}, issn = {1867-2450}, doi = {10.1007/s12551-017-0343-x}, author = {North, Rachel A and Horne, Christopher R and Davies, James S and Remus, Daniela M and Muscroft-Taylor, Andrew C and Goyal, Parveen and Wahlgren, Weixiao Yuan and Ramaswamy, S and Friemann, Rosmarie and Dobson, Renwick C J} } @article {1189, title = {Local injections of tacrolimus-loaded hydrogel reduce systemic immunosuppression-related toxicity in vascularized composite allotransplantation.}, journal = {Transplantation}, year = {2018}, month = {2018 May 23}, abstract = {

BACKGROUND: Routine application of vascularized composite allotransplantation (VCA) is hampered by immunosuppression-related health comorbidities. To mitigate these we developed an inflammation-responsive hydrogel for local immunosuppression. Here we report on its long-term effect on graft survival, immunological and toxicological impact.

METHODS: Brown Norway-to-Lewis rat hind limb transplantations were treated either systemically with daily injections of 1 mg/kg tacrolimus or with subcutaneous intragraft injections of hydrogel containing 7 mg tacrolimus, every 70 days. Animals were monitored for rejection or other pathology for 280 days. Systemic and graft tacrolimus levels, regulatory T cells, and donor cell chimerism were measured periodically. At endpoint, markers for kidney, liver and metabolic state were compared to na{\"\i}ve age-matched rats.

RESULTS: Both daily systemic tacrolimus and subcutaneous intragraft tacrolimus hydrogel at 70 day intervals were able to sustain graft survival for \>280 days in 5 out of 6 recipients. In the hydrogel group, 1 graft progressed to grade 3 rejection at postoperative day (POD) 149. In systemic tacrolimus group, 1 animal was euthanized due to lymphoma on POD 275. Hydrogel treatment provided stable graft- and reduced systemic tacrolimus levels, and a 4 times smaller total tacrolimus dose compared with systemic immunosuppression. Hydrogel-treated animals showed preserved kidney function, absence of malignancies or opportunistic infections and increased hematopoietic chimerism compared to systemic immunosuppression.

CONCLUSIONS: Our findings demonstrate that localized immunosuppression with tacrolimus hydrogel is a long-term safe and reliable treatment. It may reduce the burden of systemic immunosuppression in VCA, potentially boosting the clinical application of this surgical intervention.

}, issn = {1534-6080}, doi = {10.1097/TP.0000000000002283}, author = {Dzhonova, Dzhuliya V and Olariu, Radu and Leckenby, Jonathan and Banz, Yara and Prost, Jean-Christophe and Dhayani, Ashish and Vemula, Praveen K and Voegelin, Esther and Taddeo, Adriano and Rieben, Robert} } @article {1592, title = {Local release of tacrolimus from hydrogel-based drug delivery system is controlled by inflammatory enzymes in vivo and can be monitored non-invasively using in vivo imaging.}, journal = {PLoS One}, volume = {13}, year = {2018}, month = {2018}, pages = {e0203409}, abstract = {

BACKGROUND: Local drug delivery systems that adjust the release of immunosuppressive drug in response to the nature and intensity of inflammation represent a promising approach to reduce systemic immunosuppression and its side effects in allotransplantation. Here we aimed to demonstrate that release of tacrolimus from triglycerol monostearate hydrogel is inflammation-dependent in vivo. We further report that by loading the hydrogel with a near-infrared dye, it is possible to monitor drug release non-invasively in an in vivo model of vascularized composite allotransplantation.

MATERIALS AND METHODS: Inflammation was induced by local challenge with lipopolysaccharides in na{\"\i}ve rats 7 days after injection of tacrolimus-loaded hydrogel in the hind limb. Tacrolimus levels in blood and tissues were measured at selected time points. A near-infrared dye was encapsulated in the hydrogel together with tacrolimus in order to monitor hydrogel deposits and drug release in vitro and in vivo in a model of vascularized composite allotransplantation.

RESULTS: Injection of lipopolysaccharides led to increased blood and skin tacrolimus levels (p = 0.0076, day 7 vs. day 12 in blood, and p = 0.0007 in treated limbs, 48 h after injection compared to controls). Moreover, lipopolysaccharides-injected animals had higher tacrolimus levels in treated limbs compared to contralateral limbs (p = 0.0003 for skin and p = 0.0053 for muscle). Imaging of hydrogel deposits and tacrolimus release was achieved by encapsulating near-infrared dye in the hydrogel for 160 days. The correlation of tacrolimus and near-infrared dye release from hydrogel was R2 = 0.6297 and R2 = 0.5619 in blood and grafts of transplanted animals respectively and R2 = 0.6066 in vitro.

CONCLUSIONS: Here we demonstrate the inflammation-responsiveness of a tacrolimus-loaded hydrogel in vivo. Moreover, we show that encapsulating a near-infrared dye in the hydrogel provides a reliable correlation of tacrolimus and dye release from the hydrogel, and an accessible non-invasive method for monitoring drug release from hydrogel deposits.

}, keywords = {Animals, Drug Delivery Systems, Humans, Hydrogels, Immunosuppressive Agents, Inflammation, Male, Rats, Rats, Inbred BN, Rats, Inbred Lew, Tacrolimus}, issn = {1932-6203}, doi = {10.1371/journal.pone.0203409}, author = {Dzhonova, Dzhuliya and Olariu, Radu and Leckenby, Jonathan and Dhayani, Ashish and Vemula, Praveen Kumar and Prost, Jean-Christophe and Banz, Yara and Taddeo, Adriano and Rieben, Robert} } @article {1577, title = {Quantification of Neurotransmitters from Intact and Regenerating Planarians Using UHPLC-MS/SRM Method.}, journal = {Methods Mol Biol}, volume = {1774}, year = {2018}, month = {2018}, pages = {555-570}, abstract = {

Freshwater planarian species S. mediterranea is an emerging stem cell model because of its capability of regenerating large portions of missing body parts. It is one of the best model systems available to address the basic biological mechanisms in the regeneration processes. Absolute quantification of metabolites from planarians is imperative to understand their role in the regeneration processes. Here we describe a stable isotope dilution ultrahigh performance liquid chromatography/mass spectrometry/selected reaction monitoring (UHPLC-MS/SRM) assay for a sensitive and quantitative assessment of neurotransmitters (NTs) in planaria. We used this method for the simultaneous quantification of 16 NTs from both intact and regenerating planarians.

}, keywords = {Animals, Chromatography, High Pressure Liquid, Neurotransmitter Agents, Planarians, Regeneration, Stem Cells, Tandem Mass Spectrometry}, issn = {1940-6029}, doi = {10.1007/978-1-4939-7802-1_25}, author = {Rangiah, Kannan and Palakodeti, Dasaradhi} } @article {1616, title = {Reflections on current Ayurveda research.}, journal = {J Ayurveda Integr Med}, volume = {9}, year = {2018}, month = {2018 Oct - Dec}, pages = {250-251}, abstract = {

The current development in modern biology partnered with technology, better understanding of genes, environment is beginning to allow predicting the state of the human body. Research in Modern science is in transitional state from reverse pharmacology to system approach. It{\textquoteright}s time for Ayurveda to undertake research deep in its own foundational theories and in its interface with modern science. The present environment, lifestyle and nutrition have drastically different from ancient times. There is a need to modernize Ayurveda and make it relevant and contextual in terms of personalized medicine where allopathic medicine is heading. Innovations based on advancements, new treatment regimen, therapeutic approaches are the current needs from Ayurveda to make an impact on global clinical practice. In India, the Ayurveda research needs commitment in leadership and good funding resources for its best run, and for true healthcare.

}, issn = {0975-9476}, doi = {10.1016/j.jaim.2018.11.001}, author = {Ramaswamy, S} } @article {1187, title = {Sequence diversity of tubulin isotypes in regulation of the mitochondrial voltage-dependent anion channel.}, journal = {J Biol Chem}, year = {2018}, month = {2018 May 18}, abstract = {

The microtubule protein tubulin is a heterodimer comprising α/β subunits, in which each subunit features multiple isotypes in vertebrates. For example, seven α-tubulin and eight β-tubulin isotypes in the human tubulin gene family vary mostly in the length and primary sequence of the disordered anionic C-terminal tails (CTTs). The biological reason for such sequence diversity remains a topic of vigorous enquiry. Here, we demonstrate that it may be a key feature of tubulin{\textquoteright}s role in regulation of the permeability of the mitochondrial outer membrane voltage-dependent anion channel (VDAC). Using recombinant yeast α/β-tubulin constructs with α-CTTs, β-CTTs, or both from various human tubulin isotypes, we probed their interactions with VDAC reconstituted into planar lipid bilayers. A comparative study of the blockage kinetics revealed that either α-CTTs or β-CTTs block VDAC pore and that the efficiency of blockage by individual CTTs spans two orders of magnitude, depending on the CTT isotype. β-Tubulin constructs, notably β3, blocked VDAC most effectively. We quantitatively describe these experimental results using a physical model that accounts only for the number and distribution of charges in the CTT, and not for the interactions between specific residues on the CTT and VDAC pore. Based on these results, we speculate that the effectiveness of VDAC regulation by tubulin depends on the predominant tubulin isotype in a cell. Consequently, the fluxes of ATP/ADP through the channel could vary significantly depending on the isotype, thus suggesting an intriguing link between VDAC regulation and the diversity of tubulin isotypes present in vertebrates.

}, issn = {1083-351X}, doi = {10.1074/jbc.RA117.001569}, author = {Rostovtseva, Tatiana K and Gurnev, Philip A and Hoogerheide, David P and Rovini, Amandine and Sirajuddin, Minhajuddin and Bezrukov, Sergey M} } @article {1588, title = {The Sodium Sialic Acid Symporter From Has Altered Substrate Specificity.}, journal = {Front Chem}, volume = {6}, year = {2018}, month = {2018}, pages = {233}, abstract = {

Mammalian cell surfaces are decorated with complex glycoconjugates that terminate with negatively charged sialic acids. Commensal and pathogenic bacteria can use host-derived sialic acids for a competitive advantage, but require a functional sialic acid transporter to import the sugar into the cell. This work investigates the sodium sialic acid symporter (SiaT) from (SiaT). We demonstrate that SiaT rescues an strain lacking its endogenous sialic acid transporter when grown on the sialic acids -acetylneuraminic acid (Neu5Ac) or -glycolylneuraminic acid (Neu5Gc). We then develop an expression, purification and detergent solubilization system for SiaT and demonstrate that the protein is largely monodisperse in solution with a stable monomeric oligomeric state. Binding studies reveal that SiaT has a higher affinity for Neu5Gc over Neu5Ac, which was unexpected and is not seen in another SiaT homolog. We develop a homology model and use comparative sequence analyses to identify substitutions in the substrate-binding site of SiaT that may explain the altered specificity. SiaT is shown to be electrogenic, and transport is dependent upon more than one Na ion for every sialic acid molecule. A functional sialic acid transporter is essential for the uptake and utilization of sialic acid in a range of pathogenic bacteria, and developing new inhibitors that target these transporters is a valid mechanism for inhibiting bacterial growth. By demonstrating a route to functional recombinant SiaT, and developing the and assay systems, our work underpins the design of inhibitors to this transporter.

}, issn = {2296-2646}, doi = {10.3389/fchem.2018.00233}, author = {North, Rachel A and Wahlgren, Weixiao Y and Remus, Daniela M and Scalise, Mariafrancesca and Kessans, Sarah A and Dunevall, Elin and Claesson, Elin and Soares da Costa, Tatiana P and Perugini, Matthew A and Ramaswamy, S and Allison, Jane R and Indiveri, Cesare and Friemann, Rosmarie and Dobson, Renwick C J} } @article {1599, title = {A strategy to identify a ketoreductase that preferentially synthesizes pharmaceutically relevant (S)-alcohols using whole-cell biotransformation.}, journal = {Microb Cell Fact}, volume = {17}, year = {2018}, month = {2018 Dec 03}, pages = {192}, abstract = {

INTRODUCTION: Chemical industries are constantly in search of an expeditious and environmentally benign method for producing chiral synthons. Ketoreductases have been used as catalysts for enantioselective conversion of desired prochiral ketones to their corresponding alcohol. We chose reported promiscuous ketoreductases belonging to different protein families and expressed them in E.\ coli to evaluate their ability as whole-cell catalysts for obtaining chiral alcohol intermediates of pharmaceutical importance. Apart from establishing a method to produce high value (S)-specific alcohols that have not been evaluated before, we propose an in silico analysis procedure\ to predict product chirality.

RESULTS: Six enzymes originating from Sulfolobus\ sulfotaricus, Zygosaccharomyces\ rouxii, Hansenula\ polymorpha, Corynebacterium sp. ST-10, Synechococcus sp. PCC\ 7942 and Bacillus sp. ECU0013 with reported efficient activity for dissimilar substrates are compared here to arrive at an optimal enzyme for the method. Whole-cell catalysis of ketone intermediates for drugs like Aprepitant, Sitagliptin and Dolastatin using E.\ coli over-expressing these enzymes yielded (S)-specific chiral alcohols. We explain this chiral specificity for the best-performing enzyme, i.e., Z.\ rouxii ketoreductase using in silico modelling and MD simulations. This rationale was applied to five additional ketones that are used in the synthesis of Crizotinib, MA-20565\ (an antifungal agent), Sulopenem, Rivastigmine, Talampanel and Barnidipine and predicted the yield of (S) enantiomers. Experimental evaluation matched the in silico analysis wherein ~ 95\% (S)-specific alcohol with a chemical yield of 23-79\% was obtained through biotransformation. Further, the cofactor re-cycling was optimized by switching the carbon source from glucose to sorbitol that improved the chemical yield to 85-99\%.

CONCLUSIONS: Here, we present a strategy to synthesize pharmaceutically relevant chiral alcohols by ketoreductases using a cofactor balanced whole-cell catalysis scheme that is useful for the industry. Based on the results obtained in these trials, Zygosaccharomyces\ rouxii ketoreductase was identified as a proficient enzyme to obtain (S)-specific alcohols from their respective ketones. The whole-cell catalyst when combined with nutrient modulation of using sorbitol as a carbon source helped obtain high enantiomeric and chemical yield.

}, keywords = {Biotransformation, Catalysis, Ethanol, Ketones}, issn = {1475-2859}, doi = {10.1186/s12934-018-1036-2}, author = {Haq, Saiful F and Shanbhag, Anirudh P and Karthikeyan, Subbulakshmi and Hassan, Imran and Thanukrishnan, Kannan and Ashok, Abhishek and Sukumaran, Sunilkumar and Ramaswamy, S and Bharatham, Nagakumar and Datta, Santanu and Samant, Shalaka and Katagihallimath, Nainesh} } @article {1147, title = {Substrate-bound outward-open structure of a Na-coupled sialic acid symporter reveals a new Na site.}, journal = {Nat Commun}, volume = {9}, year = {2018}, month = {2018 May 01}, pages = {1753}, abstract = {

Many pathogenic bacteria utilise sialic acids as an energy source or use them as an external coating to evade immune detection. As such, bacteria that colonise sialylated environments deploy specific transporters to mediate import of scavenged sialic acids. Here, we report a substrate-bound 1.95 {\r A} resolution structure and subsequent characterisation of SiaT, a sialic acid transporter from Proteus mirabilis. SiaT is a secondary active transporter of the sodium solute symporter (SSS) family, which use Na gradients to drive the uptake of extracellular substrates. SiaT adopts the LeuT-fold and is in an outward-open conformation in complex with the sialic acid N-acetylneuraminic acid and two Na ions. One Na binds to the conserved Na2 site, while the second Na binds to a new position, termed Na3, which is conserved in many SSS family members. Functional and molecular dynamics studies validate the substrate-binding site and demonstrate that both Na sites regulate N-acetylneuraminic acid transport.

}, issn = {2041-1723}, doi = {10.1038/s41467-018-04045-7}, author = {Wahlgren, Weixiao Y and Dunevall, Elin and North, Rachel A and Paz, Aviv and Scalise, Mariafrancesca and Bisignano, Paola and Bengtsson-Palme, Johan and Goyal, Parveen and Claesson, Elin and Caing-Carlsson, Rhawnie and Andersson, Rebecka and Beis, Konstantinos and Nilsson, Ulf J and Farewell, Anne and Pochini, Lorena and Indiveri, Cesare and Grabe, Michael and Dobson, Renwick C J and Abramson, Jeff and Ramaswamy, S and Friemann, Rosmarie} } @article {1580, title = {Targeting Phosphopeptide Recognition by the Human BRCA1 Tandem BRCT Domain to Interrupt BRCA1-Dependent Signaling.}, journal = {Cell Chem Biol}, volume = {25}, year = {2018}, month = {2018 06 21}, pages = {677-690.e12}, abstract = {

Intracellular signals triggered by DNA breakage flow through proteins containing BRCT (BRCA1 C-terminal) domains. This family, comprising 23 conserved phosphopeptide-binding modules in man, is inaccessible to small-molecule chemical inhibitors. Here, we develop Bractoppin, a drug-like inhibitor of phosphopeptide recognition by the human BRCA1 tandem (t)BRCT domain, which selectively inhibits substrate binding with nanomolar potency in\ vitro. Structure-activity exploration suggests that Bractoppin engages BRCA1 tBRCT residues recognizing pSer in the consensus motif, pSer-Pro-Thr-Phe, plus an abutting hydrophobic pocket that is distinct in structurally related BRCT domains, conferring selectivity. In cells, Bractoppin inhibits substrate recognition detected by F{\"o}rster resonance energy transfer, and diminishes BRCA1 recruitment to DNA breaks, in turn suppressing damage-induced G2 arrest and assembly of the recombinase, RAD51. But damage-induced MDC1 recruitment, single-stranded DNA (ssDNA) generation, and TOPBP1 recruitment remain unaffected. Thus, an inhibitor of phosphopeptide recognition selectively interrupts BRCA1 tBRCT-dependent signals evoked by DNA damage.

}, issn = {2451-9448}, doi = {10.1016/j.chembiol.2018.02.012}, author = {Periasamy, Jayaprakash and Kurdekar, Vadiraj and Jasti, Subbarao and Nijaguna, Mamatha B and Boggaram, Sanjana and Hurakadli, Manjunath A and Raina, Dhruv and Kurup, Lokavya Meenakshi and Chintha, Chetan and Manjunath, Kavyashree and Goyal, Aneesh and Sadasivam, Gayathri and Bharatham, Kavitha and Padigaru, Muralidhara and Potluri, Vijay and Venkitaraman, Ashok R} } @article {1146, title = {Towards an arthritis flare-responsive drug delivery system.}, journal = {Nat Commun}, volume = {9}, year = {2018}, month = {2018 Apr 03}, pages = {1275}, abstract = {

Local delivery of therapeutics for the treatment of inflammatory arthritis (IA) is limited by short intra-articular half-lives. Since IA severity often fluctuates over time, a local drug delivery method that titrates drug release to arthritis activity would represent an attractive paradigm in IA therapy. Here we report the development of a hydrogel platform that exhibits disassembly and drug release controlled by the concentration of enzymes expressed during arthritis flares. In vitro, hydrogel loaded with triamcinolone acetonide (TA) releases drug on-demand upon exposure to enzymes or synovial fluid from patients with rheumatoid arthritis. In arthritic mice, hydrogel loaded with a fluorescent dye demonstrates flare-dependent disassembly measured as loss of fluorescence. Moreover, a single dose of TA-loaded hydrogel but not the equivalent dose of locally injected free TA reduces arthritis activity in the injected paw. Together, our data suggest flare-responsive hydrogel as a promising next-generation drug delivery approach for the treatment of IA.

}, issn = {2041-1723}, doi = {10.1038/s41467-018-03691-1}, author = {Joshi, Nitin and Yan, Jing and Levy, Seth and Bhagchandani, Sachin and Slaughter, Kai V and Sherman, Nicholas E and Amirault, Julian and Wang, Yufeng and Riegel, Logan and He, Xueyin and Rui, Tan Shi and Valic, Michael and Vemula, Praveen K and Miranda, Oscar R and Levy, Oren and Gravallese, Ellen M and Aliprantis, Antonios O and Ermann, Joerg and Karp, Jeffrey M} } @article {1594, title = {A versatile LC-MS/MS approach for comprehensive, quantitative analysis of central metabolic pathways.}, journal = {Wellcome Open Res}, volume = {3}, year = {2018}, month = {2018}, pages = {122}, abstract = {

Liquid chromatography-mass spectrometry (LC-MS/MS) based approaches are widely used for the identification and quantitation of specific metabolites, and are a preferred approach towards analyzing cellular metabolism. Most methods developed come with specific requirements such as unique columns, ion-pairing reagents and pH conditions, and typically allow measurements in a specific pathway alone. Here, we present a single column-based set of methods for simultaneous coverage of multiple pathways, primarily focusing on central carbon, amino acid, and nucleotide metabolism. We further demonstrate the use of this method for quantitative, stable isotope-based metabolic flux experiments, expanding its use beyond steady-state level measurements of metabolites. The expected kinetics of label accumulation pertinent to the pathway under study are presented with some examples. The methods discussed here are broadly applicable, minimize the need for multiple chromatographic resolution methods, and highlight how simple labeling experiments can be valuable in facilitating a comprehensive understanding of the metabolic state of cells.

}, issn = {2398-502X}, doi = {10.12688/wellcomeopenres.14832.1}, author = {Walvekar, Adhish and Rashida, Zeenat and Maddali, Hemanth and Laxman, Sunil} } @article {1185, title = {Crystal structure of N-acetylmannosamine kinase from Fusobacterium nucleatum.}, journal = {Acta Crystallogr F Struct Biol Commun}, volume = {73}, year = {2017}, month = {2017 Jun 01}, pages = {356-362}, abstract = {

Sialic acids comprise a varied group of nine-carbon amino sugars that are widely distributed among mammals and higher metazoans. Some human commensals and bacterial pathogens can scavenge sialic acids from their environment and degrade them for use as a carbon and nitrogen source. The enzyme N-acetylmannosamine kinase (NanK; EC 2.7.1.60) belongs to the transcriptional repressors, uncharacterized open reading frames and sugar kinases (ROK) superfamily. NanK catalyzes the second step of the sialic acid catabolic pathway, transferring a phosphate group from adenosine 5{\textquoteright}-triphosphate to the C6 position of N-acetylmannosamine to generate N-acetylmannosamine 6-phosphate. The structure of NanK from Fusobacterium nucleatum was determined to 2.23 {\r A} resolution by X-ray crystallography. Unlike other NanK enzymes and ROK family members, F. nucleatum NanK does not have a conserved zinc-binding site. In spite of the absence of the zinc-binding site, all of the major structural features of enzymatic activity are conserved.

}, keywords = {Adenosine Triphosphate, Amino Acid Sequence, Bacterial Proteins, Binding Sites, Cloning, Molecular, Crystallography, X-Ray, Escherichia coli, Fusobacterium nucleatum, Gene Expression, Genetic Vectors, Hexosamines, Models, Molecular, Phosphotransferases (Alcohol Group Acceptor), Protein Binding, Protein Conformation, alpha-Helical, Protein Conformation, beta-Strand, Protein Interaction Domains and Motifs, Protein Multimerization, Recombinant Proteins, Sequence Alignment, Sequence Homology, Amino Acid, Substrate Specificity}, issn = {2053-230X}, doi = {10.1107/S2053230X17007439}, author = {Caing-Carlsson, Rhawnie and Goyal, Parveen and Sharma, Amit and Ghosh, Swagatha and Setty, Thanuja Gangi and North, Rachel A and Friemann, Rosmarie and Ramaswamy, S} } @article {1160, title = {Cytoplasmic poly (A)-binding protein critically regulates epidermal maintenance and turnover in the planarian .}, journal = {Development}, volume = {144}, year = {2017}, month = {2017 09 01}, pages = {3066-3079}, abstract = {

Identifying key cellular events that facilitate stem cell function and tissue organization is crucial for understanding the process of regeneration. Planarians are powerful model system to study regeneration and stem cell (neoblast) function. Here, using planaria, we show that the initial events of regeneration, such as epithelialization and epidermal organization are critically regulated by a novel cytoplasmic poly A-binding protein, SMED-PABPC2. Knockdown leads to defects in epidermal lineage specification, disorganization of epidermis and ECM, and deregulated wound healing, resulting in the selective failure of neoblast proliferation near the wound region. Polysome profiling suggests that epidermal lineage transcripts, including , are translationally regulated by SMED-PABPC2 Together, our results uncover a novel role for SMED-PABPC2 in the maintenance of epidermal and ECM integrity, critical for wound healing and subsequent processes for regeneration.

}, keywords = {Animals, Cell Lineage, Cell Proliferation, Cytoplasm, Epidermis, Epithelium, Extracellular Matrix, Gene Knockdown Techniques, Homeostasis, Models, Biological, Planarians, Poly(A)-Binding Protein I, Regeneration, RNA, Messenger, Wound Healing}, issn = {1477-9129}, doi = {10.1242/dev.152942}, author = {Bansal, Dhiru and Kulkarni, Jahnavi and Nadahalli, Kavana and Lakshmanan, Vairavan and Krishna, Srikar and Sasidharan, Vidyanand and Geo, Jini and Dilipkumar, Shilpa and Pasricha, Renu and Gulyani, Akash and Raghavan, Srikala and Palakodeti, Dasaradhi} } @article {1204, title = {Horse Liver Alcohol Dehydrogenase: Zinc Coordination and Catalysis.}, journal = {Biochemistry}, volume = {56}, year = {2017}, month = {2017 07 18}, pages = {3632-3646}, abstract = {

During catalysis by liver alcohol dehydrogenase (ADH), a water bound to the catalytic zinc is replaced by the oxygen of the substrates. The mechanism might involve a pentacoordinated zinc or a double-displacement reaction with participation by a nearby glutamate residue, as suggested by studies of human ADH3, yeast ADH1, and some other tetrameric ADHs. Zinc coordination and participation of water in the enzyme mechanism were investigated by X-ray crystallography. The apoenzyme and its complex with adenosine 5{\textquoteright}-diphosphoribose have an open protein conformation with the catalytic zinc in one position, tetracoordinated by Cys-46, His-67, Cys-174, and a water molecule. The bidentate chelators 2,2{\textquoteright}-bipyridine and 1,10-phenanthroline displace the water and form a pentacoordinated zinc. The enzyme-NADH complex has a closed conformation similar to that of ternary complexes with coenzyme and substrate analogues; the coordination of the catalytic zinc is similar to that found in the apoenzyme, except that a minor, alternative position for the catalytic zinc is \~{}1.3 {\r A} from the major position and closer to Glu-68, which could form the alternative coordination to the catalytic zinc. Complexes with NADH and N-1-methylhexylformamide or N-benzylformamide (or with NAD and fluoro alcohols) have the classical tetracoordinated zinc, and no water is bound to the zinc or the nicotinamide rings. The major forms of the enzyme in the mechanism have a tetracoordinated zinc, where the carboxylate group of Glu-68 could participate in the exchange of water and substrates on the zinc. Hydride transfer in the Michaelis complexes does not involve a nearby water.

}, keywords = {2,2{\textquoteright}-Dipyridyl, Adenosine Diphosphate Ribose, Alcohol Dehydrogenase, Animals, Catalytic Domain, Crystallography, X-Ray, Formamides, Horses, Kinetics, Liver, Models, Molecular, NAD, Phenanthrolines, Protein Binding, Protein Conformation, Water, Zinc}, issn = {1520-4995}, doi = {10.1021/acs.biochem.7b00446}, author = {Plapp, Bryce V and Savarimuthu, Baskar Raj and Ferraro, Daniel J and Rubach, Jon K and Brown, Eric N and Ramaswamy, S} } @article {1211, title = {Mimicking Muscle Stem Cell Quiescence in Culture: Methods for Synchronization in Reversible Arrest.}, journal = {Methods Mol Biol}, volume = {1556}, year = {2017}, month = {2017}, pages = {283-302}, abstract = {

Growing evidence supports the view that in adult stem cells, the defining stem cell features of potency and self-renewal are associated with the quiescent state. Thus, uncovering the molecular logic of this reversibly arrested state underlies not only a fundamental understanding of adult tissue dynamics but also hopes for therapeutic regeneration and rejuvenation of damaged or aging tissue. A key question concerns how adult stem cells use quiescence to establish or reinforce the property of self-renewal. Since self-renewal is largely studied by assays that measure proliferation, the concept of self-renewal programs imposed during non-proliferating conditions is counterintuitive. However, there is increasing evidence generated by deconstructing the quiescent state that highlights how programs characteristic of this particular cell cycle exit may enhance stem cell capabilities, through both cell-intrinsic and extrinsic programs.Toward this end, culture models that recapitulate key aspects of stem cell quiescence are useful for molecular analysis to explore attributes and regulation of the quiescent state. In this chapter, we review the different methods used to generate homogeneous populations of quiescent muscle cells, largely by manipulating culture conditions that feed into core signaling programs that regulate the cell cycle. We also provide detailed protocols developed or refined in our lab over the past two decades.

}, keywords = {Actins, Adult Stem Cells, Animals, Biomarkers, Cell Culture Techniques, Cell Differentiation, Cell Line, Cell Proliferation, Fluorescent Antibody Technique, Humans, Mice, Microscopy, Fluorescence, Muscle, Skeletal, Myoblasts, Resting Phase, Cell Cycle, Satellite Cells, Skeletal Muscle, Stem Cells}, issn = {1940-6029}, doi = {10.1007/978-1-4939-6771-1_15}, author = {Arora, Reety and Rumman, Mohammed and Venugopal, Nisha and Gala, Hardik and Dhawan, Jyotsna} } @article {1206, title = {{One enzyme, many reactions: structural basis for the various reactions catalyzed by naphthalene 1,2-dioxygenase}}, journal = {IUCrJ}, volume = {4}, year = {2017}, month = {Sep}, pages = {648{\textendash}656}, abstract = {

Rieske nonheme iron oxygenases (ROs) are a well studied class of enzymes. Naphthalene 1,2-dioxygenase (NDO) is used as a model to study ROs. Previous work has shown how side-on binding of oxygen to the mononuclear iron provides this enzyme with the ability to catalyze stereospecific and regiospecific {\i}t cis}-dihydroxylation reactions. It has been well documented that ROs catalyze a variety of other reactions, including mono-oxygenation, desaturation, O- and N-dealkylation, sulfoxidation {\i}t etc}. NDO itself catalyzes a variety of these reactions. Structures of NDO in complex with a number of different substrates show that the orientation of the substrate in the active site controls not only the regiospecificity and stereospecificity, but also the type of reaction catalyzed. It is proposed that the mononuclear iron-activated dioxygen attacks the atoms of the substrate that are most proximal to it. The promiscuity of delivering two products (apparently by two different reactions) from the same substrate can be explained by the possible binding of the substrate in slightly different orientations aided by the observed flexibility of residues in the binding pocket.

}, keywords = {2-dioxygenase, deoxygenation, monooxygenation, naphthalene 1, substrate orientation, sulfoxidation}, doi = {10.1107/S2052252517008223}, url = {https://doi.org/10.1107/S2052252517008223}, author = {Ferraro, Daniel J. and Okerlund, Adam and Brown, Eric and Ramaswamy, S.} } @article {1156, title = {Stimulation of hair follicle stem cell proliferation through an IL-1 dependent activation of γδT-cells.}, journal = {Elife}, volume = {6}, year = {2017}, month = {2017 Dec 04}, abstract = {

The cutaneous wound-healing program is a product of a complex interplay among diverse cell types within the skin. One fundamental process that is mediated by these reciprocal interactions is the mobilization of local stem cell pools to promote tissue regeneration and repair. Using the ablation of epidermal caspase-8 as a model of wound healing in , we analyzed the signaling components responsible for epithelial stem cell proliferation. We found that IL-1α and IL-7 secreted from keratinocytes work in tandem to expand the activated population of resident epidermal γδT-cells. A downstream effect of activated γδT-cells is the preferential proliferation of hair follicle stem cells. By contrast, IL-1α-dependent stimulation of dermal fibroblasts optimally stimulates epidermal stem cell proliferation. These findings provide new mechanistic insights into the regulation and function of epidermal cell-immune cell interactions and into how components that are classically associated with inflammation can differentially influence distinct stem cell niches within a tissue.

}, issn = {2050-084X}, doi = {10.7554/eLife.28875}, author = {Lee, Pedro and Gund, Rupali and Dutta, Abhik and Pincha, Neha and Rana, Isha and Ghosh, Subhasri and Witherden, Deborah and Kandyba, Eve and MacLeod, Amanda and Kobielak, Krzysztof and Havran, Wendy L and Jamora, Colin} } @article {1203, title = {Structural and functional studies of ferredoxin and oxygenase components of 3-nitrotoluene dioxygenase from Diaphorobacter sp. strain DS2.}, journal = {PLoS One}, volume = {12}, year = {2017}, month = {2017}, pages = {e0176398}, abstract = {

3-nitrotoluene dioxygenase (3NTDO) from Diaphorobacter sp. strain DS2 catalyses the conversion of 3-nitrotoluene (3NT) into a mixture of 3- and 4-methylcatechols with release of nitrite. We report here, X-ray crystal structures of oxygenase and ferredoxin components of 3NTDO at 2.9 {\r A} and 2.4 {\r A}, respectively. The residues responsible for nitrite release in 3NTDO were further probed by four single and two double mutations in the catalytic site of α-subunit of the dioxygenase. Modification of Val 350 to Phe, Ile 204 to Ala, and Asn258 to Val by site directed mutagenesis resulted in inactive enzymes revealing the importance of these residues in catalysis. Docking studies of meta nitrotoluene to the active site of 3NTDO suggested possible orientations of binding that favor the formation of 3-methylcatechol (3MC) over 4-methylcatechol energetically. The electron transfer pathway from ferredoxin subunit to the active site of the oxygenase subunit is also proposed.

}, keywords = {Catalytic Domain, Comamonadaceae, Crystallography, X-Ray, Ferredoxins, Molecular Docking Simulation, Mutation, Oxygenases, Substrate Specificity, Toluene}, issn = {1932-6203}, doi = {10.1371/journal.pone.0176398}, author = {Kumari, Archana and Singh, Deepak and Ramaswamy, S and Ramanathan, Gurunath} } @article {1167, title = {Blue protein with red fluorescence.}, journal = {Proc Natl Acad Sci U S A}, volume = {113}, year = {2016}, month = {2016 10 11}, pages = {11513-11518}, abstract = {

The walleye (Sander vitreus) is a golden yellow fish that inhabits the Northern American lakes. The recent sightings of the blue walleye and the correlation of its sighting to possible increased UV radiation have been proposed earlier. The underlying molecular basis of its adaptation to increased UV radiation is the presence of a protein (Sandercyanin)-ligand complex in the mucus of walleyes. Degradation of heme by UV radiation results in the formation of Biliverdin IXα (BLA), the chromophore bound to Sandercyanin. We show that Sandercyanin is a monomeric protein that forms stable homotetramers on addition of BLA to the protein. A structure of the Sandercyanin-BLA complex, purified from the fish mucus, reveals a glycosylated protein with a lipocalin fold. This protein-ligand complex absorbs light in the UV region (λ of 375 nm) and upon excitation at this wavelength emits in the red region (λ of 675 nm). Unlike all other known biliverdin-bound fluorescent proteins, the chromophore is noncovalently bound to the protein. We provide here a molecular rationale for the observed spectral properties of Sandercyanin.

}, keywords = {Biliverdine, Crystallography, X-Ray, Fluorescence, Models, Molecular, Proteins, Recombinant Proteins}, issn = {1091-6490}, doi = {10.1073/pnas.1525622113}, author = {Ghosh, Swagatha and Yu, Chi-Li and Ferraro, Daniel J and Sudha, Sai and Pal, Samir Kumar and Schaefer, Wayne F and Gibson, David T and Ramaswamy, S} } @article {616, title = {Mechanistic implications from structures of yeast alcohol dehydrogenase complexed with coenzyme and an alcohol.}, journal = {Arch Biochem Biophys}, volume = {591}, year = {2016}, month = {2016 Feb 1}, pages = {35-42}, abstract = {

Yeast alcohol dehydrogenase I is a homotetramer of subunits with 347 amino acid residues, catalyzing the oxidation of alcohols using NAD(+) as coenzyme. A new X-ray structure was determined at 3.0 {\r A} where both subunits of an asymmetric dimer bind coenzyme and trifluoroethanol. The tetramer is a pair of back-to-back dimers. Subunit A has a closed conformation and can represent a Michaelis complex with an appropriate geometry for hydride transfer between coenzyme and alcohol, with the oxygen of 2,2,2-trifluoroethanol ligated at 2.1 {\r A} to the catalytic zinc in the classical tetrahedral coordination with Cys-43, Cys-153, and His-66. Subunit B has an open conformation, and the coenzyme interacts with amino acid residues from the coenzyme binding domain, but not with residues from the catalytic domain. Coenzyme appears to bind to and dissociate from the open conformation. The catalytic zinc in subunit B has an alternative, inverted coordination with Cys-43, Cys-153, His-66 and the carboxylate of Glu-67, while the oxygen of trifluoroethanol is 3.5 {\r A} from the zinc. Subunit B may represent an intermediate in the mechanism after coenzyme and alcohol bind and before the conformation changes to the closed form and the alcohol oxygen binds to the zinc and displaces Glu-67.

}, keywords = {Alcohol Dehydrogenase, Binding Sites, Catalysis, Coenzymes, Computer Simulation, Enzyme Activation, Models, Chemical, Models, Molecular, NAD, Protein Binding, Protein Conformation, Saccharomyces cerevisiae Proteins, Substrate Specificity, Trifluoroethanol}, issn = {1096-0384}, doi = {10.1016/j.abb.2015.12.009}, author = {Plapp, Bryce V and Charlier, Henry A and Ramaswamy, S} } @article {1168, title = {Sterile Inflammation Enhances ECM Degradation in Integrin β1 KO Embryonic Skin.}, journal = {Cell Rep}, volume = {16}, year = {2016}, month = {2016 09 20}, pages = {3334-3347}, abstract = {

Epidermal knockout of integrin β1 results in complete disorganization of the basement membrane (BM), resulting in neonatal lethality. Here, we report that this disorganization is exacerbated by an early\ embryonic inflammatory response involving the recruitment of tissue-resident and monocyte-derived macrophages to the dermal-epidermal junction, associated with increased matrix metalloproteinase activity. Remarkably, the skin barrier in the integrin β1 knockout animals is intact, suggesting that this inflammatory response is initiated in a sterile environment. We demonstrate that the molecular mechanism involves de novo expression of integrin αvβ6 in the basal epidermal cells, which activates a TGF-β1 driven inflammatory cascade resulting in upregulation of dermal NF-κB in a Tenascin C-dependent manner. Importantly, treatment of β1 KO embryos in utero with small molecule inhibitors of TGF-βR1 and NF-κB results in marked rescue of the BM defects and amelioration of immune response, revealing an unconventional immuno-protective role for integrin β1 during BM remodeling.

}, keywords = {Animals, Extracellular Matrix, Inflammation, Integrin beta1, Macrophages, Mice, Mice, Knockout, Signal Transduction, Skin}, issn = {2211-1247}, doi = {10.1016/j.celrep.2016.08.062}, author = {Kurbet, Ambika S and Hegde, Samarth and Bhattacharjee, Oindrila and Marepally, Srujan and Vemula, Praveen K and Raghavan, Srikala} } @article {1173, title = {Stochastic steps in secondary active sugar transport.}, journal = {Proc Natl Acad Sci U S A}, volume = {113}, year = {2016}, month = {2016 07 05}, pages = {E3960-6}, abstract = {

Secondary active transporters, such as those that adopt the leucine-transporter fold, are found in all domains of life, and they have the unique capability of harnessing the energy stored in ion gradients to accumulate small molecules essential for life as well as expel toxic and harmful compounds. How these proteins couple ion binding and transport to the concomitant flow of substrates is a fundamental structural and biophysical question that is beginning to be answered at the atomistic level with the advent of high-resolution structures of transporters in different structural states. Nonetheless, the dynamic character of the transporters, such as ion/substrate binding order and how binding triggers conformational change, is not revealed from static structures, yet it is critical to understanding their function. Here, we report a series of molecular simulations carried out on the sugar transporter vSGLT that lend insight into how substrate and ions are released from the inward-facing state of the transporter. Our simulations reveal that the order of release is stochastic. Functional experiments were designed to test this prediction on the human homolog, hSGLT1, and we also found that cytoplasmic release is not ordered, but we confirmed that substrate and ion binding from the extracellular space is ordered. Our findings unify conflicting published results concerning cytoplasmic release of ions and substrate and hint at the possibility that other transporters in the superfamily may lack coordination between ions and substrate in the inward-facing state.

}, keywords = {Glucose, HEK293 Cells, Humans, Markov Chains, Molecular Dynamics Simulation, Monte Carlo Method, Patch-Clamp Techniques, Sodium, Sodium-Glucose Transporter 1}, issn = {1091-6490}, doi = {10.1073/pnas.1525378113}, author = {Adelman, Joshua L and Ghezzi, Chiara and Bisignano, Paola and Loo, Donald D F and Choe, Seungho and Abramson, Jeff and Rosenberg, John M and Wright, Ernest M and Grabe, Michael} } @article {621, title = {Structure of a heterogeneous, glycosylated, lipid-bound, {\i}t in vivo-grown protein crystal at atomic resolution from the viviparous cockroach {\i}t Diploptera punctata}, journal = {IUCrJ}, volume = {3}, year = {2016}, month = {Jul}, pages = {282{\textendash}293}, abstract = {

Macromolecular crystals for X-ray diffraction studies are typically grown {\i}t in vitro} from pure and homogeneous samples; however, there are examples of protein crystals that have been identified {\i}t in vivo}. Recent developments in micro-crystallography techniques and the advent of X-ray free-electron lasers have allowed the determination of several protein structures from crystals grown {\i}t in cellulo}. Here, an atomic resolution (1.2{\AA}) crystal structure is reported of heterogeneous milk proteins grown inside a living organism in their functional niche. These {\i}t in vivo}-grown crystals were isolated from the midgut of an embryo within the only known viviparous cockroach, {\i}t Diploptera punctata}. The milk proteins crystallized in space group {\i}t P}1, and a structure was determined by anomalous dispersion from the native S atoms. The data revealed glycosylated proteins that adopt a lipocalin fold, bind lipids and organize to form a tightly packed crystalline lattice. A single crystal is estimated to contain more than three times the energy of an equivalent mass of dairy milk. This unique storage form of nourishment for developing embryos allows access to a constant supply of complete nutrients. Notably, the crystalline cockroach-milk proteins are highly heterogeneous with respect to amino-acid sequence, glycosylation and bound fatty-acid composition. These data present a unique example of protein heterogeneity within a single {\i}t in vivo}-grown crystal of a natural protein in its native environment at atomic resolution.

}, keywords = {glycosylation, protein heterogeneity, sulfur-SAD, viviparity in cockroach}, doi = {10.1107/S2052252516008903}, url = {http://dx.doi.org/10.1107/S2052252516008903}, author = {Banerjee, Sanchari and Coussens, Nathan P. and Gallat, Fran{\c c}ois-Xavier and Sathyanarayanan, Nitish and Srikanth, Jandhyam and Yagi, Koichiro J. and Gray, James S. S. and Tobe, Stephen S. and Stay, Barbara and Chavas, Leonard M. G. and Ramaswamy, Subramanian} } @article {399, title = {Mechanistic heterogeneity in contractile properties of α-tropomyosin (TPM1) mutants associated with inherited cardiomyopathies.}, journal = {J Biol Chem}, volume = {290}, year = {2015}, month = {2015 Mar 13}, pages = {7003-15}, abstract = {

The most frequent known causes of primary cardiomyopathies are mutations in the genes encoding sarcomeric proteins. Among those are 30 single-residue mutations in TPM1, the gene encoding α-tropomyosin. We examined seven mutant tropomyosins, E62Q, D84N, I172T, L185R, S215L, D230N, and M281T, that were chosen based on their clinical severity and locations along the molecule. The goal of our study was to determine how the biochemical characteristics of each of these mutant proteins are altered, which in turn could provide a structural rationale for treatment of the cardiomyopathies they produce. Measurements of Ca(2+) sensitivity of human β-cardiac myosin ATPase activity are consistent with the hypothesis that hypertrophic cardiomyopathies are hypersensitive to Ca(2+) activation, and dilated cardiomyopathies are hyposensitive. We also report correlations between ATPase activity at maximum Ca(2+) concentrations and conformational changes in TnC measured using a fluorescent probe, which provide evidence that different substitutions perturb the structure of the regulatory complex in different ways. Moreover, we observed changes in protein stability and protein-protein interactions in these mutants. Our results suggest multiple mechanistic pathways to hypertrophic and dilated cardiomyopathies. Finally, we examined a computationally designed mutant, E181K, that is hypersensitive, confirming predictions derived from in silico structural analysis.

}, keywords = {Actins, Adenosine Triphosphatases, Calcium, Cardiomyopathies, Humans, Models, Molecular, Myosins, Point Mutation, Protein Stability, Tropomyosin}, issn = {1083-351X}, doi = {10.1074/jbc.M114.596676}, author = {Gupte, Tejas M and Haque, Farah and Gangadharan, Binnu and Sunitha, Margaret S and Mukherjee, Souhrid and Anandhan, Swetha and Rani, Deepa Selvi and Mukundan, Namita and Jambekar, Amruta and Thangaraj, Kumarasamy and Sowdhamini, Ramanathan and Sommese, Ruth F and Nag, Suman and Spudich, James A and Mercer, John A} } @article {2271, title = {A quantitative metabolomics peek into planarian regeneration.}, journal = {Analyst}, volume = {140}, year = {2015}, month = {2015 May 21}, pages = {3445-64}, abstract = {

The fresh water planarian species Schmidtea mediterranea is an emerging stem cell model because of its capability to regenerate a whole animal from a small piece of tissue. It is one of the best model systems to address the basic mechanisms essential for regeneration. Here, we are interested in studying the roles of various amines, thiols and nucleotides in planarian regeneration, stem cell function and growth. We developed mass spectrometry based quantitative methods and validated the differential enrichment of 35 amines, 7 thiol metabolites and 4 nucleotides from both intact and regenerating planarians. Among the amines, alanine in sexual and asparagine in asexual are the highest (\>1000 ng/mg) in the intact planarians. The levels of thiols such as cysteine and GSH are 651 and 1107 ng mg(-1) in planarians. Among the nucleotides, the level of cGMP is the lowest (0.03 ng mg(-1)) and the level of AMP is the highest (187 ng mg(-1)) in both of the planarian strains. We also noticed increasing levels of amines in both anterior and posterior regenerating planarians. The blastema from day 3 regenerating planarians also showed higher amounts of many amines. Interestingly, the thiol (cysteine and GSH) levels are well maintained during planarian regeneration. This suggests an inherent and effective mechanism to control induced oxidative stress because of the robust regeneration and stem cell proliferation. Like in intact planarians, the level of cGMP is also very low in regenerating planarians. Surprisingly, the levels of amines and thiols in head regenerating blastemas are \~{}3 times higher compared to those for tail regenerating blastemas. Thus our results strongly indicate the potential roles of amines, thiols and nucleotides in planarian regeneration.

}, keywords = {Animals, Calibration, Chromatography, High Pressure Liquid, Limit of Detection, Metabolomics, Planarians, Reference Standards, Regeneration, Reproduction, Asexual, Species Specificity, Tandem Mass Spectrometry}, issn = {1364-5528}, doi = {10.1039/c4an02037e}, author = {Natarajan, Nivedita and Ramakrishnan, Padma and Lakshmanan, Vairavan and Palakodeti, Dasaradhi and Rangiah, Kannan} }