Phosphorylation-independent desensitization of G protein-coupled receptors?
G protein-coupled receptors (GPCRs) are involved in a multitude of signaling processes and respond to a wide range of ligands. The activity of GPCRs is subject to three principal modes of regulation: desensitization, trafficking, and down-regulation. Desensitization is defined as a loss in the responsiveness of a signaling system. The generally established paradigm for GPCR desensitization involves receptor phosphorylation by GPCR kinases (GRKs), initiated by agonist-induced conformational changes in the receptor or by kinases activated by specific signaling pathways. GRKs have several interaction domains and may be able to contribute to receptor desensitization through mechanisms that do not involve the kinase activity of GRK. Pao and Benovic discuss some of these interactions and their relevance for the regulation of GPCR signaling.
Pao
Christina S
CS
The Kimmel Cancer Center, Department of Microbiology and Immunology, Thomas Jefferson University, 233 South 10th Street, Philadelphia, PA 19107, USA.
Benovic
Jeffrey L
JL
D019204:GTP-Binding Proteins / Q000378:metabolism*; D006160:Guanosine Triphosphate / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism; D010766:Phosphorylation; D011485:Protein Binding; D011956:Receptors, Cell Surface / Q000378:metabolism*; D015398:Signal Transduction
D008565:Membrane Proteins; D011956:Receptors, Cell Surface; D006160:Guanosine Triphosphate; D019204:GTP-Binding Proteins