Anti-RGP4 antibodies are used in antigen-specific immunodetection in biological samples. The target RGP4 is a known alias name of the protein regulator of G protein signaling 4, encoded by the RGS4 gene in humans. This 205-amino acid residue protein 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. In terms of tissue expression, it is reported to be expressed in the brain and heart.