cd05608: STKc_GRK1 (this model, PSSM-Id:173699 is obsolete and has been replaced by 270759)
Catalytic domain of the Protein Serine/Threonine Kinase, G protein-coupled Receptor Kinase 1
Serine/Threonine Kinases (STKs), G protein-coupled Receptor Kinase (GRK) subfamily, GRK1 isoform, catalytic (c) domain. STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. The GRK subfamily is part of a larger superfamily that includes the catalytic domains of other protein STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase. GRKs phosphorylate and regulate G protein-coupled receptors (GPCRs), the largest superfamily of cell surface receptors, which regulate some part of nearly all physiological functions. Phosphorylated GPCRs bind to arrestins, which prevents further G protein signaling despite the presence of activating ligand. There are seven types of GRKs, named GRK1 to GRK7. GRK1, also called rhodopsin kinase, belongs to the visual group of GRKs and is expressed in retinal cells. It phosphorylates rhodopsin in rod cells, which leads to termination of the phototransduction cascade. Mutations in GRK1 are associated to a recessively inherited form of stationary nightblindness called Oguchi disease.