Members of the RGS (regulator of G protein signaling) family, such as RGS6, modulate G protein function by activating the intrinsic GTPase activity of the alpha (guanine nucleotide-binding) subunits.Members of the RGS (regulator of G protein signaling) family have been shown to modulate the functioning of G proteins by activating the intrinsic GTPase activity of the alpha (guanine nucleotide-binding) subunits.[supplied by OMIM].