Open AccessThe coupling of the M2 muscarinic receptor to its G protein is voltage dependent
Author(s) -
Yair Ben-Chaim,
Chava Broide,
H. Parnas
Publication year - 2019
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0224367
Subject(s) - g protein coupled receptor , g protein , agonist , microbiology and biotechnology , signal transduction , coupling (piping) , muscarinic acetylcholine receptor , biology , xenopus , receptor , muscarinic agonist , biophysics , chemistry , biochemistry , materials science , gene , metallurgy
G protein coupled receptors (GPCRs) participate in the majority of signal transduction processes in the body. Specifically, the binding of an external agonist promotes coupling of the GPCR to its G protein and this, in turn, induces downstream signaling. Recently, it was shown that agonist binding to the M2 muscarinic receptor (M2R) and to other GPCRs is voltage dependent. Here we examine, whether the coupling of the M2R to its G protein is also voltage-dependent. We first show, in Xenopus oocytes, that the activity of the M2R in the absence of agonist (constitutive activity) can be used to report the coupling. We then show that the coupling is, by itself, voltage dependent. This novel finding is of physiological importance, as it shows that the actual signal transduction, whose first step is the coupling of the GPCR to its cognate G protein, is voltage dependent.