RT Journal Article SR Electronic T1 Cholesterol Dependence of the Conformational Changes in Metabotropic Glutamate Receptor 1 JF bioRxiv FD Cold Spring Harbor Laboratory SP 2024.04.17.589854 DO 10.1101/2024.04.17.589854 A1 Isu, Ugochi H. A1 Badiee, Shadi A. A1 Polasa, Adithya A1 Tabari, Seyed H. A1 Derakhshani-Molayousefi, Mortaza A1 Moradi, Mahmoud YR 2024 UL http://biorxiv.org/content/early/2024/04/20/2024.04.17.589854.abstract AB Metabotropic glutamate receptors (mGluRs) are class C G protein-coupled receptors that function as obligate dimers in regulating neurotransmission and synaptic plasticity in the central nervous system. The mGluR1 subtype has been shown to be modulated by the membrane lipid environment, particularly cholesterol, though the molecular mechanisms remain elusive. In this study, we employed all-atom molecular dynamics simulations to investigate the effects of cholesterol on the conformational dynamics of the mGluR1 seven-transmembrane (7TM) domain in an inactive state model. Simulations were performed with three different cholesterol concentrations (0%, 10%, and 25%) in a palmitoyl-oleoyl phosphatidylcholine (POPC) lipid bilayer system. Our results demonstrate that cholesterol induces conformational changes in the mGluR1 dimer more significantly than in the individual protomers. Notably, cholesterol modulates the dynamics and conformations of the TM1 and TM2 helices at the dimer interface. Interestingly, an intermediate cholesterol concentration of 10% elicits more pronounced conformational changes compared to both cholesterol-depleted (0%) and cholesterol-enriched (25%) systems. Specific electrostatic interaction unique to the 10% cholesterol system further corroborate these conformational differences. Given the high sequence conservation of the 7TM domains across mGluR subtypes, the cholesterol-dependent effects observed in mGluR1 are likely applicable to other members of this receptor family. Our findings provide atomistic insights into how cholesterol modulates the conformational landscape of mGluRs, which could impact their function and signaling mechanisms.Competing Interest StatementThe authors have declared no competing interest.