OCRL Antibody - #DF8585

Catalyzes the hydrolysis of the 4-position phosphate of phosphatidylinositol 4,5-bisphosphate (PtdIns(4,5)P2) and phosphatidylinositol-3,4,5-bisphosphate (PtdIns(3,4,5)P3), with the greatest catalytic activity towards PtdIns(4,5)P2. Able also to hydrolyzes the 4-phosphate of inositol 1,4,5-trisphosphate and of inositol 1,3,4,5-tetrakisphosphate. Regulates traffic in the endosomal pathway by regulating the specific pool of phosphatidylinositol 4,5-bisphosphate that is associated with endosomes. Involved in primary cilia assembly. Acts as a regulator of phagocytosis, hydrolyzing PtdIns(4,5)P2 to promote phagosome closure, through attenuation of PI3K signaling.

Cytoplasmic vesicle>Phagosome membrane. Early endosome membrane. Membrane>Clathrin-coated pit. Cell projection>Cilium>Photoreceptor outer segment. Cell projection>Cilium. Cytoplasmic vesicle. Endosome. Golgi apparatus>trans-Golgi network. Lysosome.
Note: Also found on macropinosomes (PubMed:25869668). Colocalized with APPL1 on phagosomes (PubMed:22072788).

Brain, skeletal muscle, heart, kidney, lung, placenta and fibroblasts. Expressed in the retina and the retinal pigment epithelium.

Interacts with APPL1, FAM109A/SES1 and FAM109B/SES2; APPL1-binding and FAM109A-binding are mutually exclusive. Interacts with clathrin heavy chain. Interacts with several Rab GTPases, at least RAB1B, RAB5A, RAB6A, RAB8A and RAB31; these interactions may play a dual role in targeting OCRL to the specific membranes and stimulating the phosphatase activity. Interaction with RAB8A modulates OCRL recruitment to cilia. Interacts with INPP5F.

The ASH (ASPM-SPD2-Hydin) and RhoGAP (Rho GTPase activating) domains form a single folding module. The ASH domain has an immunoglobulin-like fold, the Rho-GAP domain lacks the catalytic arginine and is catalytically inactive. The ASH-RhoGAP module regulates the majority of the protein-protein interactions currently described. The ASH domain mediates association with membrane-targeting Rab GTPases. The Rho-GAP domain interacts with the endocytic adapter APPL1, which is then displaced by FAM109A and FAM109B as endosomes mature.

Belongs to the inositol 1,4,5-trisphosphate 5-phosphatase type II family.