RGS22 (regulator of G-protein signaling 22), also known as FLJ75004, PRTD-NY2, FLJ40080, MGC102908 or DKFZp434I092, is a novel 1264 amino acid regulator of G-protein signaling specific to to testis. RGS22 inhibits signal transduction and contains two isoforms as a result of alternative splicing. RGS22 is found in spermatogenic cells and Leydig cells, and may be involved in the translocation of GNA13 from the cytoplasm to the nucleus during spermiogenesis. RGS22 contains two RGS domains: RGS1 and RGS2, and the gene encoding RGS22 maps to human chromosome 8q22.2.