G protein-coupled receptor, class C, group 6, member A (GPRC6A) is a receptor activated by amino acids with a preference for basic amino acids such as L-Lys, L-Arg and L-ornithine but also by small and polar amino acids. The L-alpha amino acids respond is augmented by divalent cations Ca2+ and Mg2+. GPRC6A is activated by extracellular calcium and osteocalin. It mediates the non-genomic effects of androgens in multiple tissue and coordinate nutritional and hormonal anabolic signals through the sensing of extracellular amino acids, osteocalcin, divalents ions and its responsiveness to anabolic steroids. References: The UniProt Consortium. Nucleic Acids Res. 47: D506-515 (2019); Nucleic Acids Res. 2016 Jan 4;44(D1):D733-45, PMID:26553804