IUBMB Enzyme Nomenclature


Accepted name: phosphatidylinositol-3,4-bisphosphate 4-phosphatase

Reaction: 1-phosphatidyl-myo-inositol 3,4-bisphosphate + H2O = 1-phosphatidyl-1D-myo-inositol 3-phosphate + phosphate

For diagram click here.

Glossary: inositol 3-phosphate = Ins-3-P
inositol 1,3-bisphosphate = Ins(1,3)P2
inositol 3,4-bisphosphate = Ins(3,4)P2
inositol 1,3,4-trisphosphate = Ins(1,3,4)P3
1-phosphatidyl-1D-myo-inositol 3-phosphate = PtdIns3P
1-phosphatidyl-1D-myo-inositol 4-phosphate = PtdIns4P

Other name(s): inositol-3,4-bisphosphate 4-phosphatase; D-myo-inositol-3,4-bisphosphate 4-phosphohydrolase; phosphoinositide 4-phosphatase; inositol polyphosphate 4-phosphatase; D-myo-inositol-3,4-bisphosphate 4-phosphohydrolase; inositol polyphosphate 4-phosphatase type II

Systematic name: 1-phosphatidyl-1D-myo-inositol-3,4-bisphosphate 4-phosphohydrolase

Comments: Mg2+-independent. This enzyme still works when the 2,3-bis(acyloxy)propyl group is removed, i.e., it hydrolyses Ins(1,3,4)P3 to Ins(1,3)P2. It also converts Ins(3,4)P2 into Ins-3-P.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 123644-80-4


1. Howell, S., Barnaby, R.J., Rowe, T., Ragan, C.I. and Gee, N.S. Evidence for at least four different inositol bisphosphatases in bovine brain. Eur. J. Biochem. 183 (1989) 169-172. [PMID: 2546770]

2. Norris, F.A., Auethavekiat, V. and Majerus, P.W. The isolation and characterization of cDNA encoding human and rat brain inositol polyphosphate 4-phosphatase. J. Biol. Chem. 270 (1995) 16128-16133. [PMID: 7608176]

3. Norris, F.A., Atkins, R.C. and Majerus, P.W. The cDNA cloning and characterization of inositol polyphosphate 4-phosphatase type II. Evidence for conserved alternative splicing in the 4-phosphatase family. J. Biol. Chem. 272 (1997) 23859-23864. [PMID: 9295334]

[EC created 1992, modified 2002]

Return to EC 3.1.3 home page
Return to EC 3.1 home page
Return to EC 3 home page
Return to Enzymes home page
Return to IUBMB Biochemical Nomenclature home page