RhoGAP_OCRL1: RhoGAP (GTPase-activator protein [GAP] for Rho-like small GTPases) domain present in OCRL1-like proteins. OCRL1 (oculocerebrorenal syndrome of Lowe 1)-like proteins contain two conserved domains: a central inositol polyphosphate 5-phosphatase domain and a C-terminal Rho GAP domain, this GAP domain lacks the catalytic residue and therefore maybe inactive. OCRL-like proteins are type II inositol polyphosphate 5-phosphatases that can hydrolyze lipid PI(4,5)P2 and PI(3,4,5)P3 and soluble Ins(1,4,5)P3 and Ins(1,3,4,5)P4, but their individual specificities vary. The functionality of the RhoGAP domain is still unclear. 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.
Jiyao W et al.(2023). "The conserved domain database in 2023.",