Department of Biotechnology
inStem (Institute for Stem Cell Science and Regenerative Medicine)

Distinct regulation of bioenergetics and translation by group I mGluR and NMDAR.

Publication Type

Research Support, Non-U.S. Gov't

Date of Publication

June 4, 2020

Journal

EMBO reports

Volume/Issue

21/6

ISSN

1469-3178

Neuronal activity is responsible for the high energy consumption in the brain. However, the cellular mechanisms draining ATP upon the arrival of a stimulus are yet to be explored systematically at the post-synapse. Here, we provide evidence that a significant fraction of ATP is consumed upon glutamate stimulation to energize mGluR-induced protein synthesis. We find that both mGluR and NMDAR alter protein synthesis and ATP consumption with distinct kinetics at the synaptic-dendritic compartments. While mGluR activation leads to a rapid and sustained reduction in neuronal ATP levels, NMDAR activation has no immediate impact on the same. ATP consumption correlates inversely with the kinetics of protein synthesis for both receptors. We observe a persistent elevation in protein synthesis within 5 minutes of mGluR activation and a robust inhibition of the same within 2 minutes of NMDAR activation, assessed by the phosphorylation status of eEF2 and metabolic labeling. However, a delayed protein synthesis-dependent ATP expenditure ensues after 15 minutes of NMDAR stimulation. We identify a central role for AMPK in the correlation between protein synthesis and ATP consumption. AMPK is dephosphorylated and inhibited upon mGluR activation, while it is phosphorylated upon NMDAR activation. Perturbing AMPK activity disrupts receptor-specific modulations of eEF2 phosphorylation and protein synthesis. Our observations, therefore, demonstrate that the regulation of the AMPK-eEF2 signaling axis by glutamate receptors alters neuronal protein synthesis and bioenergetics.

Alternate Journal

EMBO Rep

PubMed ID

32351028

PubMed Central ID

PMC7271334

Authors

Sudhriti Ghosh Dastidar
Shreya Das Sharma
Sumita Chakraborty
Sumantra Chattarji
Aditi Bhattacharya
Ravi S Muddashetty

Keywords

Energy Metabolism
Phosphorylation
Receptors, N-Methyl-D-Aspartate
Synapses
Peptide Elongation Factor 2