This intronless gene belongs to a family of RAS-related genes. The proteins encoded by these genes share approximately 50% amino acid identity with the classical RAS proteins and have numerous structural features in common. The most striking difference between the RAP and RAS proteins resides in their 61st amino acid: glutamine in RAS is replaced by threonine in RAP proteins. Evidence suggests that this protein may be polyisoprenylated and palmitoylated. [provided by RefSeq, Jul 2008].