Crystal structure of a common GPCR-binding interface for G protein and arrestin.

ABSTRACT: G-protein-coupled receptors (GPCRs) transmit extracellular signals to activate intracellular heterotrimeric G proteins (Gαβγ) and arrestins. For G protein signalling, the Gα C-terminus (GαCT) binds to a cytoplasmic crevice of the receptor that opens upon activation. A consensus motif is shared among GαCT from the Gi/Gt family and the 'finger loop' region (ArrFL1-4) of all four arrestins. Here we present a 2.75 Å crystal structure of ArrFL-1, a peptide analogue of the finger loop of rod photoreceptor arrestin, in complex with the prototypical GPCR rhodopsin. Functional binding of ArrFL to the receptor was confirmed by ultraviolet-visible absorption spectroscopy, competitive binding assays and Fourier transform infrared spectroscopy. For both GαCT and ArrFL, binding to the receptor crevice i

SUBMITTER: Szczepek M 

PROVIDER: S-EPMC4199108 | biostudies-literature | 2014 Sep

REPOSITORIES: biostudies-literature