Related Experiment Video
Updated: Mar 2, 2026

Strategic Screening and Characterization of the Visual GPCR-mini-G Protein Signaling Complex for Successful Crystallization
Published on: March 16, 2020
Molecular assembly of rhodopsin with G protein-coupled receptor kinases
Yuanzheng He1, Xiang Gao1, Devrishi Goswami2,3
1Laboratory of Structural Sciences, Center for Structural Biology and Drug Discovery, Van Andel Research Institute, Grand Rapids, MI 49503, USA.
Abstract:
G protein-coupled receptor kinases (GRKs) play pivotal roles in desensitizing GPCR signaling but little is known about how GRKs recognize and phosphorylate GPCRs due to the technical difficulties in detecting the highly dynamic GPCR/GRK interaction. By combining a genetic approach with multiple biochemical assays, we identified the key determinants for the assembly of the prototypical GPCR rhodopsin with its kinase GRK1. Our work reveals that the regulatory G-protein signaling homology (RH) domain of GRKs is the primary binding site to GPCRs and an active conformation of the GRK1 kinase domain is required for efficient interaction with rhodopsin. In addition, we provide a mechanistic solution for the longstanding puzzle about the gain-of-function Q41L mutation in GRK5. This mutation is in the RH domain and increases the capacity of the GRK mutant to interact with and to desensitize GPCRs. Finally we present the principal architecture of a rhodopsin/GRK complex through negative stain electron microscopy reconstruction. Together, these data define the key components for the rhodopsin/GRK1 interaction and provide a framework for understanding GRK-mediated desensitization of GPCRs.
Related Concept Videos
Channel Rhodopsins
Rhodopsins belong to the family of cell surface proteins called G-protein coupled receptors,...
Activation and Inactivation of G Proteins
Assembly of Signaling Complexes
Interaction domains in cell signaling
Interaction domains recognize exposed features of their binding partners containing post-translationally modified sequences,...
G Protein-coupled Receptors
GPCRs are also called heptahelical, 7TM, or serpentine receptors, and consist of seven (H1-H7) transmembrane alpha-helices that span the bilayer to form a cylindrical core. The transmembrane helices are connected by three extracellular loops and three...
G-protein Coupled Receptors
G-Protein Gated Ion Channels
Sensory...

