Cryo-EM structure of human rhodopsin bound to an inhibitory G protein.

ABSTRACT: G-protein-coupled receptors comprise the largest family of mammalian transmembrane receptors. They mediate numerous cellular pathways by coupling with downstream signalling transducers, including the hetrotrimeric G proteins G_s (stimulatory) and G_i (inhibitory) and several arrestin proteins. The structural mechanisms that define how G-protein-coupled receptors selectively couple to a specific type of G protein or arrestin remain unknown. Here, using cryo-electron microscopy, we show that the major interactions between activated rhodopsin and G_i are mediated by the C-terminal helix of the G_i α-subunit, which is wedged into the cytoplasmic cavity of the transmembrane helix bundle and directly contacts the amino terminus of helix 8 of rhodopsin. Str

SUBMITTER: Kang Y 

PROVIDER: S-EPMC8054211 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature