| Comment type | Description |
|---|
| Alternative Products | Event=Alternative splicing; Named isoforms=3; Name=1; IsoId=Q8K337-1; Sequence=Displayed; Name=2; IsoId=Q8K337-2; Sequence=VSP_042226, VSP_042227; Name=3; IsoId=Q8K337-3; Sequence=VSP_042224, VSP_042225; |
| Catalytic Activity | 1-phosphatidyl-1D-myo-inositol 4,5- bisphosphate + H(2)O = 1-phosphatidyl-1D-myo-inositol 4-phosphate + phosphate. {ECO:0000269|PubMed:9525932}. |
| Domain | 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, all three interactions relie on F&H motifs, an approximately 12-13 amino-acid sequence centered around Phe and His residues essential for binding (By similarity). {ECO:0000250}. |
| Function | Hydrolyzes phosphatidylinositol 4,5-bisphosphate (PtIns(4,5)P2) and the signaling molecule phosphatidylinositol 1,4,5-trisphosphate (PtIns(1,4,5)P3), and thereby modulates cellular signaling events. {ECO:0000269|PubMed:11311145, ECO:0000269|PubMed:9525932}. |
| Ptm | Isoprenylation at Cys-990 may be required for localization at the membrane. {ECO:0000250}. |
| Ptm | May be proteolytically cleaved after Lys-320 as inferred from N-terminal protein sequence of the 75 kda form. {ECO:0000250}. |
| Sequence Caution | Sequence=AAB95412.2; Type=Erroneous initiation; Note=Translation N-terminally extended.; Evidence={ECO:0000305}; |
| Similarity | Belongs to the inositol 1,4,5-trisphosphate 5- phosphatase type II family. {ECO:0000305}. |
| Similarity | Contains 1 PH domain. {ECO:0000305}. |
| Similarity | Contains 1 Rho-GAP domain. {ECO:0000255|PROSITE- ProRule:PRU00172}. |
| Subcellular Location | Cytoplasm, cytosol. Endoplasmic reticulum- Golgi intermediate compartment {ECO:0000250}. Early endosome membrane. Membrane; Peripheral membrane protein; Cytoplasmic side. Cytoplasmic vesicle, phagosome membrane. Golgi apparatus {ECO:0000250}. |
| Subunit | Interacts with APPL1, FAM109A and FAM109B. Interacts with several Rab GTPases, at least RAB1A, RAB2A, RAB5A, RAB6A, RAB8A, RAB9A and RAB33B; these interactions may play a dual role in targeting INPP5B to the specific membranes and stimulating the phosphatase activity (By similarity). {ECO:0000250}. |
| Tissue Specificity | Detected in kidney, liver, brain, lung and testis (at protein level). Detected in kidney and liver, and at lower levels in brain, lung and testis. {ECO:0000269|PubMed:9525932}. |