@article {3644, title = {Nanoarchitectonics for Free-Standing Polyelectrolyte Multilayers Films: Exploring the Flipped Surfaces}, journal = {ChemNanoMat}, year = {2022}, month = {dec}, doi = {10.1002/cnma.202200462}, url = {https://doi.org/10.1002\%2Fcnma.202200462}, author = {Suman Pahal and Rakshith Boranna and Abinash Tripathy and Venkanagouda S. Goudar and Vyshnavi T. Veetil and Rajendra Kurapati and Gurusiddappa R. Prashanth and Praveen K. Vemula} } @article {3640, title = {Nanobody derived using a peptide epitope from the spike protein receptor-binding motif inhibits entry of SARS-CoV-2 variants.}, journal = {J Biol Chem}, volume = {299}, year = {2022}, month = {2022 Nov 22}, pages = {102732}, abstract = {

The emergence of new escape mutants of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has escalated its penetration among the human population and has reinstated its status as a global pandemic. Therefore, developing effective antiviral therapy against emerging SARS-CoV variants and other viruses in a short period becomes essential. Blocking SARS-CoV-2 entry into human host cells by disrupting the spike glycoprotein-angiotensin-converting enzyme 2 interaction has already been exploited for vaccine development and monoclonal antibody therapy. Unlike the previous reports, our study used a nine-amino acid peptide from the receptor-binding motif of the spike protein as an epitope. We report the identification of an efficacious nanobody N1.2 that blocks the entry of pseudovirus-containing SARS-CoV-2 spike as the surface glycoprotein. Moreover, using mCherry fluorescence-based reporter assay, we observe a more potent neutralizing effect against both the hCoV19 (Wuhan/WIV04/2019) and the Omicron (BA.1) pseudotyped spike virus with a bivalent version of the N1.2 nanobody. In summary, our study presents a rapid and efficient methodology to use peptide sequences from a protein-receptor interaction interface as epitopes for screening nanobodies against potential pathogenic targets. We propose that this approach can also be widely extended to target other viruses and pathogens in the future.

}, issn = {1083-351X}, doi = {10.1016/j.jbc.2022.102732}, author = {Mendon, Nivya and Ganie, Rayees A and Kesarwani, Shubham and Dileep, Drisya and Sasi, Sarika and Lama, Prakash and Chandra, Anchal and Sirajuddin, Minhajuddin} } @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 {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 {2038, title = {Nucleolar localization of the Notch4 intracellular domain underpins its regulation of the cellular response to genotoxic stressors.}, journal = {Cell Death Discov}, volume = {6}, year = {2020}, month = {2020}, pages = {7}, abstract = {

Cell survival is one of the many cellular processes regulated by Notch family of proteins. A comparison of human breast cancer cell lines, which differ in the levels of endogenous Notch4, implicated the protein in regulating susceptibility to apoptosis triggered by genomic damage. In agreement with this observation, increased susceptibility to genotoxic damage was observed following siRNA ablations of Notch4 in two breast cancer cell lines. Further, overexpressing Notch4 intracellular domain (NIC4) tagged to GFP (NIC4-GFP), protected cells from apoptosis triggered by genotoxic drugs. In cells immune-stained for endogenous Notch4, protein was detected in the nucleolus and nucleoplasm, which was also confirmed by the co-localization of NIC4-GFP with RFP-tagged nucleolar proteins in breast cancer cells or the unrelated HEK cell line. Linking functional outcomes to nucleolar localization, NIC4-GFP protection from apoptosis, required the nucleolar proteins Nucleolin and Fibrillarin. Consistently, immunoprecipitation analysis revealed associations between nucleolar proteins-Nucleolin and Nucleophosmin-and Notch4. Microscopy-based biophysical analysis of live cells showed that nucleolar and nucleoplasmic pools of NIC4-GFP are mobile, with some sequestration of nucleolar NIC4-GFP pools. A nucleolar excluded form, NIC4_3RA-GFP, generated by site-directed mutagenesis of the nucleolar localization sequence in NIC4, could not protect from apoptosis triggered by genotoxic stressors. However, transcriptional activity or protection from apoptosis triggered by endoplasmic stress was comparable in cells expressing NIC4_3RA-GFP or NIC4-GFP. Together, the data show that nucleolar localization of NIC4 is critical for the regulation of genomic damage and may be uncoupled from its activities in the nucleoplasm. This study identifies intrinsic features of NIC4 that regulate signaling outcomes activated by the receptor by controlling its spatial localization.

}, issn = {2058-7716}, doi = {10.1038/s41420-020-0242-y}, author = {Saini, Neetu and Sarin, Apurva} } @article {1617, title = {Natural monomers: A mine for functional and sustainable materials {\textendash} Occurrence, chemical modification and polymerization}, journal = {Progress in Polymer Science}, volume = {92}, year = {2019}, abstract = {

Owing to the natural abundance, variety of structural features, and highly specific functions, natural monomers render themselves as potential candidates for production of high performance functional polymers. The emerging concept of the biorefinery and development of new biosynthetic routes to synthesize a versatile and broad spectrum of natural monomers and polymers continues to gain momentum. The production of high quality polymers from renewable feedstocks requires innovative chemical modifications and catalytic transformations to achieve higher yields in an efficient manner. A fresh look into monomers available from natural resources such as terpenes, rosin, glycerol, furans, tannins, suberin, their derivatives and miscellaneous monomers may inspire future applications with impactful biobased materials. There are also many areas that require urgent discussion and review pertaining to recent developments in the field; this includes monomer sources that give molecules having special structural features. In particular, cardanol, a naturally occurring low-molecular-weight compound is unique as it contains a phenolic head group and a hydrocarbon chain with different degrees of unsaturation. This molecule possesses functional groups that are amenable for classical chemical modification, which is instrumental in developing a wide range of functional monomers and polymers. A large number of soft and hard materials have been developed from cardanol-based monomers. During the past, a large number of industrial grade materials have been developed from plant-based monomers, including development from microbial and fermentation processes (i.e. lactic acid). This review provides a comprehensive study and survey on recent developments on monomers and polymers derived from urushiol and cardanol based monomers and polymers, vegetable oil-based monomers and polymers, microbially produced monomers and polymers. These all represent emerging fronts giving a vast scope while highlighting important potential material and reagent opportunities.

}, url = {https://www.sciencedirect.com/science/article/pii/S0079670018300273}, author = {John, G., and Nagarajan, S., and Vemula, P. K., and Silverman, J.R., and Pillai, C. K. S.} } @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 {1984, title = {Novel Series of Methyl 3-(Substituted Benzoyl)-7-Substituted-2-Phenylindolizine-1-Carboxylates as Promising Anti-Inflammatory Agents: Molecular Modeling Studies.}, journal = {Biomolecules}, volume = {9}, year = {2019}, month = {2019 Oct 28}, abstract = {

The cyclooxygenase-2 (COX-2) enzyme is considered to be an important target for developing novel anti-inflammatory agents. Selective COX-2 inhibitors offer the advantage of lower adverse effects that are commonly associated with non-selective COX inhibitors. In this work, a novel series of methyl 3-(substituted benzoyl)-7-substituted-2-phenylindolizine-1-carboxylates was synthesized and evaluated for COX-2 inhibitory activity. Compound was identified as the most active compound of the series with an IC of 6.71 M, which is comparable to the IC of indomethacin, a marketed non-steroidal anti-inflammatory drug (NSAID). Molecular modeling and crystallographic studies were conducted to further characterize the compounds and gain better understanding of the binding interactions between the compounds and the residues at the active site of the COX-2 enzyme. The pharmacokinetic properties and potential toxic effects were predicted for all the synthesized compounds, which indicated good drug-like properties. Thus, these synthesized compounds can be considered as potential lead compounds for developing effective anti-inflammatory therapeutic agents.

}, issn = {2218-273X}, doi = {10.3390/biom9110661}, author = {Venugopala, Katharigatta N and Al-Attraqchi, Omar H A and Tratrat, Christophe and Nayak, Susanta K and Morsy, Mohamed A and Aldhubiab, Bandar E and Attimarad, Mahesh and Nair, Anroop B and Sreeharsha, Nagaraja and Venugopala, Rashmi and Haroun, Michelyne and Girish, Meravanige B and Chandrashekharappa, Sandeep and Alwassil, Osama I and Odhav, Bharti} } @article {1150, title = {Negative regulation of G2-M by ATR (mei-41)/Chk1(Grapes) facilitates tracheoblast growth and tracheal hypertrophy in Drosophila.}, journal = {Elife}, volume = {7}, year = {2018}, month = {2018 Apr 16}, abstract = {

Imaginal progenitors in Drosophila are known to arrest in G2 during larval stages and proliferate thereafter. Here we investigate the mechanism and implications of G2 arrest in progenitors of the adult thoracic tracheal epithelium (tracheoblasts). We report that tracheoblasts pause in G2 for ~48-56 h and grow in size over this period. Surprisingly, tracheoblasts arrested in G2 express drivers of G2-M like Cdc25/String (Stg). We find that mechanisms that prevent G2-M are also in place in this interval. Tracheoblasts activate Checkpoint Kinase 1/Grapes (Chk1/Grp) in an ATR/mei-41-dependent manner. Loss of ATR/Chk1 led to precocious mitotic entry ~24-32 h earlier. These divisions were apparently normal as there was no evidence of increased DNA damage or cell death. However, induction of precocious mitoses impaired growth of tracheoblasts and the tracheae they comprise. We propose that ATR/Chk1 negatively regulate G2-M in developing tracheoblasts and that G2 arrest facilitates cellular and hypertrophic organ growth.

}, issn = {2050-084X}, doi = {10.7554/eLife.29988}, author = {Kizhedathu, Amrutha and Bagul, Archit V and Guha, Arjun} } @article {1186, title = {Networks that link cytoskeletal regulators and diaphragm proteins underpin filtration function in Drosophila nephrocytes.}, journal = {Exp Cell Res}, volume = {364}, year = {2018}, month = {2018 Mar 15}, pages = {234-242}, abstract = {

Insect nephrocytes provide a valuable model for kidney disease, as they are structurally and functionally homologous to mammalian kidney podocytes. They possess an exceptional macromolecular assembly, the nephrocyte diaphragm (ND), which serves as a filtration barrier and helps maintain tissue homeostasis by filtering out wastes and toxic products. However, the elements that maintain nephrocyte architecture and the ND are not understood. We show that Drosophila nephrocytes have a unique cytoplasmic cluster of F-actin, which is maintained by the microtubule cytoskeleton and Rho-GTPases. A balance of Rac1 and Cdc42 activity as well as proper microtubule organization and endoplasmic reticulum structure, are required to position the actin cluster. Further, ND proteins Sns and Duf also localize to this cluster and regulate organization of the actin and microtubule cytoskeleton. Perturbation of any of these inter-dependent components impairs nephrocyte ultrafiltration. Thus cytoskeletal components, Rho-GTPases and ND proteins work in concert to maintain the specialized nephrocyte architecture and function.

}, issn = {1090-2422}, doi = {10.1016/j.yexcr.2018.02.015}, author = {Muraleedharan, Simi and Sam, Aksah and Skaer, Helen and Inamdar, Maneesha S} } @article {615, title = {Notch1 regulated autophagy controls survival and suppressor activity of activated murine T-regulatory cells.}, journal = {Elife}, volume = {5}, year = {2016}, month = {2016}, abstract = {

Cell survival is one of several processes regulated by the Notch pathway in mammalian cells. Here we report functional outcomes of non-nuclear Notch signaling to activate autophagy, a conserved cellular response to nutrient stress, regulating survival in murine natural T-regulatory cells (Tregs), an immune subset controlling tolerance and inflammation. Induction of autophagy required ligand-dependent, Notch intracellular domain (NIC) activity, which controlled mitochondrial organization and survival of activated Tregs. Consistently, NIC immune-precipitated Beclin and Atg14, constituents of the autophagy initiation complex. Further, ectopic expression of an effector of autophagy (Atg3) or recombinant NIC tagged to a nuclear export signal (NIC-NES), restored autophagy and suppressor function in Notch1(-/-) Tregs. Furthermore, Notch1 deficiency in the Treg lineage resulted in immune hyperactivity, implicating Notch activity in Treg homeostasis. Notch1 integration with autophagy, revealed in these experiments, holds implications for Notch regulated cell-fate decisions governing differentiation.

}, issn = {2050-084X}, doi = {10.7554/eLife.14023}, author = {Marcel, Nimi and Sarin, Apurva} }