Ghrelin receptor conformational dynamics regulate the transition from a preassembled to an active receptor:Gq complex.

ABSTRACT: How G protein-coupled receptor conformational dynamics control G protein coupling to trigger signaling is a key but still open question. We addressed this question with a model system composed of the purified ghrelin receptor assembled into lipid discs. Combining receptor labeling through genetic incorporation of unnatural amino acids, lanthanide resonance energy transfer, and normal mode analyses, we directly demonstrate the occurrence of two distinct receptor:Gq assemblies with different geometries whose relative populations parallel the activation state of the receptor. The first of these assemblies is a preassembled complex with the receptor in its basal conformation. This complex is specific of Gq and is not observed with Gi. The second one is an active assembly in which the receptor

SUBMITTER: Damian M 

PROVIDER: S-EPMC4321262 | biostudies-literature | 2015 Feb

REPOSITORIES: biostudies-literature