RGS proteins are regulatory and structural components GPCR complexes. These are GAPs for Gi and Gq class G-alpha proteins and negatively regulate GPCR signaling pathways. RGS20, a 25kD protein, is a novel member of this family and is human homolog of bovine Gz-GAP. It contains an N-terminal cysteine string that is potential site for multiple palmitoylation and a C-terminal RGS core domain. RGS20 plays a vital role in regulating GPCR signals in brain, neuronal development and regulation of golgi structure. It specifically interacts and accelerates the hydrolysis of G-alphaz. Reports suggest that it interacts with G-alphai subunit and plays a significant role in regulation of G-alphai-mediated signaling. It is a membrane-bound protein specifically expressed in brain, with highest concentrations in caudate nucleus and temporal lobe.