Anti-RGS9 antibodies are used in the immunodetection of the protein regulator of G protein signaling 9. In humans, the canonical protein has a reported length of 674 amino acid residues and a mass of 77 kDa. Its subcellular localization is in the membrane. Up to 5 different isoforms have been reported for this protein. It is reported to be highly expressed in the caudate and putamen, lower levels found in the hypothalamus and nucleus accumbens and very low levels in cerebellum. RGS9 is known to inhibit signal transduction by increasing the GTPase activity of G protein alpha subunits thereby driving them into their inactive GDP-bound form. Synonyms for this target antigen include PERRS1, RGS9L, regulator of G-protein signalling 9, and PERRS. RGS9 gene orthologs have been reported in the mouse, rat, bovine, frog, chimpanzee and chicken species. Some RGS9 antibodies may have been used in research and have associated citations. Western Blot is a widely used application for these antibodies. ELISA and Immunohistochemistry are also common applications.