G protein: Ras-RasGAP complex, mol. model

Molecular model of a Ras-RasGAP complex, ribbon diagram showing how Ras sits on RasGAP. ALF4 is used in structural studies as an analogue of the gamma-phosphate of ATP. Bound nucleotide, ALF4 and arginine 789 of RasGAP are shown as ball-and-stick models; alpha-helices as cylinders. Ras proteins are the smallest G proteins comprising the common core of the G protein fold, binding GDP/GTP and having intrinsic GTPase activity. GTPase activating protein (GAP) stimulates GTPase of normal but not oncogenic RAS P21. PDB code:1wq1.