Immunogen sequence: VPKPRNRPSV PPPPQPPGVH SAGDSSLTNT APTASKIVTD SNSRVSEPHR SIFPEMHSDS ASKDVPGRIL L Antigen sequence identity: Mouse 75%; Rat 75%. RICH1 is a GTPase-activating protein (GAP). GAPs stimulate the intrinsic GTP hydrolysis of small G proteins,