RhoGAP-p50rhoGAP: RhoGAP (GTPase-activator protein [GAP] for Rho-like small GTPases) domain of p50RhoGAP-like proteins; p50RhoGAP, also known as RhoGAP-1, contains a C-terminal RhoGAP domain and an N-terminal Sec14 domain which binds phosphatidylinositol 3,4,5-trisphosphate (PtdIns(3,4,5)P3). It is ubiquitously expressed and preferentially active on Cdc42. This subgroup also contains closely related ARHGAP8. Small GTPases cluster into distinct families, and all act as molecular switches, active in their GTP-bound form but inactive when GDP-bound. The Rho family of GTPases activates effectors involved in a wide variety of developmental processes, including regulation of cytoskeleton formation, cell proliferation and the JNK signaling pathway. GTPases generally have a low intrinsic GTPase hydrolytic activity but there are family-specific groups of GAPs that enhance the rate of GTP hydrolysis by several orders of magnitude.