| Members of family C of the G protein-coupled receptor (GPCR) superfamily, such as GPRC6A, are characterized by an evolutionarily conserved amino acid-sensing motif linked to an intramembranous 7-transmembrane loop region. Several members of GPCR family C, including GPRC6A, also have a long N-terminal domain (summary by Pi et al., 2005 [PubMed 16199532]).[supplied by OMIM, Nov 2010],function:Receptor that is activated by both amino acids and extracellular concentration of calcium ions. The activity of this receptor is mediated by a G-protein that activates a phosphatidylinositol-calcium second messenger system. Senses changes in the extracellular concentration of calcium ions, suggesting that it may mediate extracellular calcium-sensing responses in osteoblasts. Osteocalin, stimulates its activity in presence of calcium. Has a lower affinity for calcium than CASR. Also acts as a receptor for amino acids, with a preference for basic amino acids such as L-Lys, L-Arg and L-ornithine. Its affinity for amino acids suggests that it may act as a regulatory component of the urea cycle.,PTM:N-glycosylated.,similarity:Belongs to the G-protein coupled receptor 3 family.,subunit:Homodimer, disulfide-linked.,tissue specificity:Widely expressed. Expressed at high level in brain, skeletal muscle, testis, bone, calvaria, osteoblasts and leukocytes. Expressed at intermediate level in liver, heart, kidney and spleen. Expressed at low level in lung, pancreas, placenta and ovary. Not expressed in thymus, prostate, small intestine, tongue and colon. In kidney, isoform 1 and isoform 2 are expressed at the same level, while in other tissues, isoform 2 is expressed at low level., |
