RAC1/MIG5 [CPTC-RAC1-1]

A large number of low molecular weight, GTP binding proteins of the Ras superfamily have been identified. These proteins regulate many fundamental processes in all eukaryotic cells such as growth, vesicle traffic and cytoskeletal organization. GTPase-activating proteins (GAPs) accelerate the intrinsic rate of GTP hydrolysis of Ras-related proteins, resulting in downregulation of their active form. RAC1 and RAC2 are 92% identical and share GTP binding and GTP hydrolysis motifs with other members of the Ras superfamily. RAC1 is expressed in a large number of different cell types. RAC1 p21/rho GDI heterodimer is the active component of the cytosolic factor sigma 1, which is involved in stimulation of the NADPH oxidase activity in macrophages (By similarity). Essential for the SPATA13-mediated regulation of cell migration and adhesion assembly and disassembly. RAC1 has been demonstrated to play a critical role in tumor progression of human colorectal adenocarcinoma cells. In one study, overexpression of Rac1 accelerated the tumorigenic process, whereas RAC1 inhibition completed suppressed tumor formation.