| Modification Notes |
Rho GAP p190-B (ARHGAP5, RhoGAP5; Rho GTPase activating protein 5, p190-B, RasGAP-associated p105 protein) negatively regulates Rho GTPases by stimulating the hydrolysis of bound GTP. Two transcript variants encoding different isoforms have been found for the human gene. Rho GAP p190-B localizes diffusely in the cytoplasm, and in fibrillar patterns that co-localize with alpha5/beta1 integrin receptor in normal human foreskin fibroblasts, RD muscle cells, and HT-1080 cells. Rho GAP p190-B interacts with transmembrane plexin receptors and mediates semaphorin signalling to the actin cytoskeleton, guiding cell migration and axon extension. Plexin activation leads to the disassembly of integrin-based focal adhesive structures and to actin cytoskeleton remodelling and inhibition of cell migration. SHP-2-dependent dephosphorylation of Rho GAP p190-B leads to the activation of RhoA in myoblasts, supporting the idea that myogenesis is under the influence of SHP-2 activity on the Rho GAP p190/RhoA pathway. |
