EC 2.7.1.149     
Accepted name: 1-phosphatidylinositol-5-phosphate 4-kinase
Reaction: ATP + 1-phosphatidyl-1D-myo-inositol 5-phosphate = ADP + 1-phosphatidyl-1D-myo-inositol 4,5-bisphosphate
Glossary: 1-phosphatidyl-1D-myo-inositol 5-phosphate = PtdIns5P
1-phosphatidyl-1D-myo-inositol 4,5-bisphosphate = PtdIns(4,5)P2
Other name(s): type II PIP kinase
Systematic name: ATP:1-phosphatidyl-1D-myo-inositol-5-phosphate 4-phosphotransferase
References:
1.  Rameh, L.E., Tolias, K.F., Duckworth, B.C. and Cantley, L.C. A new pathway for synthesis of phosphatidylinositol-4,5-bisphosphate. Nature 390 (1997) 192–196. [PMID: 9367159]
[EC 2.7.1.149 created 2002]
 
 
EC 3.1.3.78     
Accepted name: phosphatidylinositol-4,5-bisphosphate 4-phosphatase
Reaction: 1-phosphatidyl-1D-myo-inositol 4,5-bisphosphate + H2O = 1-phosphatidyl-1D-myo-inositol 5-phosphate + phosphate
Glossary: 1-phosphatidyl-1D-myo-inositol 3-phosphate = PtdIns3P
1-phosphatidyl-1D-myo-inositol 4-phosphate = PtdIns4P
1-phosphatidyl-1D-myo-inositol 5-phosphate = PtdIns5P
1-phosphatidyl-1D-myo-inositol 3,4-bisphosphate = PtdIns(3,4)P2
1-phosphatidyl-1D-myo-inositol 3,5-bisphosphate = PtdIns(3,5)P2
1-phosphatidyl-1D-myo-inositol 4,5-bisphosphate = PtdIns(4,5)P2
1-phosphatidyl-1D-myo-inositol 3,4,5-trisphosphate = PtdIns(3,4,5)P3
Other name(s): phosphatidylinositol-4,5-bisphosphate 4-phosphatase I; phosphatidylinositol-4,5-bisphosphate 4-phosphatase II; type I PtdIns-4,5-P2 4-Ptase; type II PtdIns-4,5-P2 4-Ptase; IpgD; PtdIns-4,5-P2 4-phosphatase type I; PtdIns-4,5-P2 4-phosphatase type II; type I phosphatidylinositol-4,5-bisphosphate 4-phosphatase; type 1 4-phosphatase
Systematic name: 1-phosphatidyl-1D-myo-inositol-4,5-bisphosphate 4-phosphohydrolase
Comments: Two pathways exist in mammalian cells to degrade 1-phosphatidyl-1D-myo-inositol 4,5-bisphosphate [PtdIns(4,5)P2] [2]. One is catalysed by this enzyme and the other by EC 3.1.3.36, phosphoinositide 5-phosphatase, where the product is PtdIns4P. The enzyme from human is specific for PtdIns(4,5)P2 as substrate, as it cannot use PtdIns(3,4,5)P3, PtdIns(3,4)P2, PtdIns(3,5)P2, PtdIns5P, PtdIns4P or PtdIns3P [2]. In humans, the enzyme is localized to late endosomal/lysosomal membranes [2]. It can control nuclear levels of PtdIns5P and thereby control p53-dependent apoptosis [3].
References:
1.  Niebuhr, K., Giuriato, S., Pedron, T., Philpott, D.J., Gaits, F., Sable, J., Sheetz, M.P., Parsot, C., Sansonetti, P.J. and Payrastre, B. Conversion of PtdIns(4,5)P2 into PtdIns(5)P by the S. flexneri effector IpgD reorganizes host cell morphology. EMBO J. 21 (2002) 5069–5078. [PMID: 12356723]
2.  Ungewickell, A., Hugge, C., Kisseleva, M., Chang, S.C., Zou, J., Feng, Y., Galyov, E.E., Wilson, M. and Majerus, P.W. The identification and characterization of two phosphatidylinositol-4,5-bisphosphate 4-phosphatases. Proc. Natl. Acad. Sci. USA 102 (2005) 18854–18859. [PMID: 16365287]
3.  Zou, J., Marjanovic, J., Kisseleva, M.V., Wilson, M. and Majerus, P.W. Type I phosphatidylinositol-4,5-bisphosphate 4-phosphatase regulates stress-induced apoptosis. Proc. Natl. Acad. Sci. USA 104 (2007) 16834–16839. [PMID: 17940011]
4.  Mason, D., Mallo, G.V., Terebiznik, M.R., Payrastre, B., Finlay, B.B., Brumell, J.H., Rameh, L. and Grinstein, S. Alteration of epithelial structure and function associated with PtdIns(4,5)P2 degradation by a bacterial phosphatase. J. Gen. Physiol. 129 (2007) 267–283. [PMID: 17389247]
[EC 3.1.3.78 created 2008]
 
 
EC 3.1.3.95     
Accepted name: phosphatidylinositol-3,5-bisphosphate 3-phosphatase
Reaction: 1-phosphatidyl-1D-myo-inositol 3,5-bisphosphate + H2O = 1-phosphatidyl-1D-myo-inositol 5-phosphate + phosphate
Glossary: 1-phosphatidyl-1D-myo-inositol 5-phosphate = PtdIns5P
1-phosphatidyl-1D-myo-inositol 3,5-bisphosphate = PtdIns(3,5)P2
Other name(s): MTMR; PtdIns-3,5-P2 3-Ptase
Systematic name: 1-phosphatidyl-1D-myo-inositol-3,5-bisphosphate 3-phosphohydrolase
Comments: The enzyme is found in both plants and animals. It also has the activity of EC 3.1.3.64 (phosphatidylinositol-3-phosphatase).
References:
1.  Walker, D.M., Urbe, S., Dove, S.K., Tenza, D., Raposo, G. and Clague, M.J. Characterization of MTMR3. an inositol lipid 3-phosphatase with novel substrate specificity. Curr. Biol. 11 (2001) 1600–1605. [PMID: 11676921]
2.  Berger, P., Bonneick, S., Willi, S., Wymann, M. and Suter, U. Loss of phosphatase activity in myotubularin-related protein 2 is associated with Charcot-Marie-Tooth disease type 4B1. Hum. Mol. Genet. 11 (2002) 1569–1579. [PMID: 12045210]
3.  Ding, Y., Lapko, H., Ndamukong, I., Xia, Y., Al-Abdallat, A., Lalithambika, S., Sadder, M., Saleh, A., Fromm, M., Riethoven, J.J., Lu, G. and Avramova, Z. The Arabidopsis chromatin modifier ATX1, the myotubularin-like AtMTM and the response to drought. Plant Signal. Behav. 4 (2009) 1049–1058. [PMID: 19901554]
[EC 3.1.3.95 created 2014]