| Structural highlights
Disease
[SHIP2_HUMAN] Defects in INPPL1 may be a cause of susceptibility to type 2 diabetes mellitus non-insulin dependent (NIDDM) [MIM:125853].[1] [2] Note=Genetic variations in INPPL1 may be a cause of susceptibility to metabolic syndrome. Metabolic syndrome is characterized by diabetes, insulin resistance, hypertension, and hypertriglyceridemia is absent.
Function
[SHIP2_HUMAN] Phosphatidylinositol (PtdIns) phosphatase that specifically hydrolyzes the 5-phosphate of phosphatidylinositol-3,4,5-trisphosphate (PtdIns(3,4,5)P3) to produce PtdIns(3,4)P2, thereby negatively regulating the PI3K (phosphoinositide 3-kinase) pathways. Plays a central role in regulation of PI3K-dependent insulin signaling, although the precise molecular mechanisms and signaling pathways remain unclear. While overexpression reduces both insulin-stimulated MAP kinase and Akt activation, its absence does not affect insulin signaling or GLUT4 trafficking. Confers resistance to dietary obesity. May act by regulating AKT2, but not AKT1, phosphorylation at the plasma membrane. Part of a signaling pathway that regulates actin cytoskeleton remodeling. Required for the maintenance and dynamic remodeling of actin structures as well as in endocytosis, having a major impact on ligand-induced EGFR internalization and degradation. Participates in regulation of cortical and submembraneous actin by hydrolyzing PtdIns(3,4,5)P3 thereby regulating membrane ruffling. Regulates cell adhesion and cell spreading. Required for HGF-mediated lamellipodium formation, cell scattering and spreading. Acts as a negative regulator of EPHA2 receptor endocytosis by inhibiting via PI3K-dependent Rac1 activation. Acts as a regulator of neuritogenesis by regulating PtdIns(3,4,5)P3 level and is required to form an initial protrusive pattern, and later, maintain proper neurite outgrowth. Acts as a negative regulator of the FC-gamma-RIIA receptor (FCGR2A). Mediates signaling from the FC-gamma-RIIB receptor (FCGR2B), playing a central role in terminating signal transduction from activating immune/hematopoietic cell receptor systems. Involved in EGF signaling pathway. Upon stimulation by EGF, it is recruited by EGFR and dephosphorylates PtdIns(3,4,5)P3. Plays a negative role in regulating the PI3K-PKB pathway, possibly by inhibiting PKB activity. Down-regulates Fc-gamma-R-mediated phagocytosis in macrophages independently of INPP5D/SHIP1. In macrophages, down-regulates NF-kappa-B-dependent gene transcription by regulating macrophage colony-stimulating factor (M-CSF)-induced signaling. May also hydrolyze PtdIns(1,3,4,5)P4, and could thus affect the levels of the higher inositol polyphosphates like InsP6.[3] [4] [5] [6] [7] [8] [9] [10]
Publication Abstract from PubMed
Phosphoinositides regulate many cellular processes, and cellular levels are controlled by kinases and phosphatases. SHIP2 (SH2 (Src homology 2)-domain-containing inositol-phosphatase-2) plays a critical role in phosphoinositide signaling, cleaving the 5-phosphate from phosphatidylinositol 3,4,5-trisphosphate. SHIP2 is thought to be involved in type-2 diabetes and obesity, conditions that could therefore be open to pharmacological modulation of the enzyme. However, rational design of SHIP2 inhibitors has been limited by the absence of a high-resolution structure. Here, we present a 2.1 A resolution crystal structure of the phosphatase domain of SHIP2 bound to the synthetic ligand biphenyl 2,3',4,5',6-pentakisphosphate (BiPh(2,3',4,5',6)P(5)). BiPh(2,3',4,5',6)P(5) is not a SHIP2 substrate but inhibits Ins(1,3,4,5)P(4) hydrolysis with an IC(50) of 24.8 +/- 3.0 muM, (K(m) for Ins(1,3,4,5)P(4) is 215 +/- 28 muM). Molecular dynamics simulations suggest that when BiPh(2,3',4,5',6)P(5) binds to SHIP2, a flexible loop folds over and encloses the ligand. Compounds targeting such a closed conformation might therefore deliver SHIP2-specific drugs.
A Synthetic Polyphosphoinositide Headgroup Surrogate in Complex with SHIP2 Provides a Rationale for Drug Discovery.,Mills SJ, Persson C, Cozier G, Thomas MP, Tresaugues L, Erneux C, Riley AM, Nordlund P, Potter BV ACS Chem Biol. 2012 May 18;7(5):822-8. Epub 2012 Feb 27. PMID:22330088[11]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Marion E, Kaisaki PJ, Pouillon V, Gueydan C, Levy JC, Bodson A, Krzentowski G, Daubresse JC, Mockel J, Behrends J, Servais G, Szpirer C, Kruys V, Gauguier D, Schurmans S. The gene INPPL1, encoding the lipid phosphatase SHIP2, is a candidate for type 2 diabetes in rat and man. Diabetes. 2002 Jul;51(7):2012-7. PMID:12086927
- ↑ Kagawa S, Sasaoka T, Yaguchi S, Ishihara H, Tsuneki H, Murakami S, Fukui K, Wada T, Kobayashi S, Kimura I, Kobayashi M. Impact of SRC homology 2-containing inositol 5'-phosphatase 2 gene polymorphisms detected in a Japanese population on insulin signaling. J Clin Endocrinol Metab. 2005 May;90(5):2911-9. Epub 2005 Feb 1. PMID:15687335 doi:jc.2004-1724
- ↑ Habib T, Hejna JA, Moses RE, Decker SJ. Growth factors and insulin stimulate tyrosine phosphorylation of the 51C/SHIP2 protein. J Biol Chem. 1998 Jul 17;273(29):18605-9. PMID:9660833
- ↑ Pesesse X, Dewaste V, De Smedt F, Laffargue M, Giuriato S, Moreau C, Payrastre B, Erneux C. The Src homology 2 domain containing inositol 5-phosphatase SHIP2 is recruited to the epidermal growth factor (EGF) receptor and dephosphorylates phosphatidylinositol 3,4,5-trisphosphate in EGF-stimulated COS-7 cells. J Biol Chem. 2001 Jul 27;276(30):28348-55. Epub 2001 May 10. PMID:11349134 doi:10.1074/jbc.M103537200
- ↑ Dyson JM, O'Malley CJ, Becanovic J, Munday AD, Berndt MC, Coghill ID, Nandurkar HH, Ooms LM, Mitchell CA. The SH2-containing inositol polyphosphate 5-phosphatase, SHIP-2, binds filamin and regulates submembraneous actin. J Cell Biol. 2001 Dec 10;155(6):1065-79. Epub 2001 Dec 10. PMID:11739414 doi:10.1083/jcb.200104005
- ↑ Prasad N, Topping RS, Decker SJ. Src family tyrosine kinases regulate adhesion-dependent tyrosine phosphorylation of 5'-inositol phosphatase SHIP2 during cell attachment and spreading on collagen I. J Cell Sci. 2002 Oct 1;115(Pt 19):3807-15. PMID:12235291
- ↑ Dyson JM, Munday AD, Kong AM, Huysmans RD, Matzaris M, Layton MJ, Nandurkar HH, Berndt MC, Mitchell CA. SHIP-2 forms a tetrameric complex with filamin, actin, and GPIb-IX-V: localization of SHIP-2 to the activated platelet actin cytoskeleton. Blood. 2003 Aug 1;102(3):940-8. Epub 2003 Apr 3. PMID:12676785 doi:10.1182/blood-2002-09-2897
- ↑ Pengal RA, Ganesan LP, Fang H, Marsh CB, Anderson CL, Tridandapani S. SHIP-2 inositol phosphatase is inducibly expressed in human monocytes and serves to regulate Fcgamma receptor-mediated signaling. J Biol Chem. 2003 Jun 20;278(25):22657-63. Epub 2003 Apr 10. PMID:12690104 doi:10.1074/jbc.M302907200
- ↑ Prasad NK, Decker SJ. SH2-containing 5'-inositol phosphatase, SHIP2, regulates cytoskeleton organization and ligand-dependent down-regulation of the epidermal growth factor receptor. J Biol Chem. 2005 Apr 1;280(13):13129-36. Epub 2005 Jan 24. PMID:15668240 doi:M410289200
- ↑ Zhuang G, Hunter S, Hwang Y, Chen J. Regulation of EphA2 receptor endocytosis by SHIP2 lipid phosphatase via phosphatidylinositol 3-Kinase-dependent Rac1 activation. J Biol Chem. 2007 Jan 26;282(4):2683-94. Epub 2006 Nov 29. PMID:17135240 doi:M608509200
- ↑ Mills SJ, Persson C, Cozier G, Thomas MP, Tresaugues L, Erneux C, Riley AM, Nordlund P, Potter BV. A Synthetic Polyphosphoinositide Headgroup Surrogate in Complex with SHIP2 Provides a Rationale for Drug Discovery. ACS Chem Biol. 2012 May 18;7(5):822-8. Epub 2012 Feb 27. PMID:22330088 doi:10.1021/cb200494d
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