Crystal structure of rhodopsin in complex with a mini-G_o sheds light on the principles of G protein selectivity.

ABSTRACT: Selective coupling of G protein (heterotrimeric guanine nucleotide-binding protein)-coupled receptors (GPCRs) to specific Gα-protein subtypes is critical to transform extracellular signals, carried by natural ligands and clinical drugs, into cellular responses. At the center of this transduction event lies the formation of a signaling complex between the receptor and G protein. We report the crystal structure of light-sensitive GPCR rhodopsin bound to an engineered mini-G_o protein. The conformation of the receptor is identical to all previous structures of active rhodopsin, including the complex with arrestin. Thus, rhodopsin seems to adopt predominantly one thermodynamically stable active conformation, effectively acting like a "structural switch," allowing for maximum efficien

SUBMITTER: Tsai CJ 

PROVIDER: S-EPMC6154990 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature