| Structural highlights
Disease
[PTN22_HUMAN] Defects in PTPN22 are a cause of susceptibility to systemic lupus erythematosus (SLE) [MIM:152700]. SLE is a chronic, inflammatory and often febrile multisystemic disorder of connective tissue. It affects principally the skin, joints, kidneys and serosal membranes. It is thought to represent a failure of the regulatory mechanisms of the autoimmune system.[1]
Function
[PTN22_HUMAN] Acts as negative regulator of T-cell receptor (TCR) signaling by direct dephosphorylation of the Src family kinases LCK and FYN, ITAMs of the TCRz/CD3 complex, as well as ZAP70, VAV, VCP and other key signaling molecules. Associates with and probably dephosphorylates CBL. Dephosphorylates LCK at its activating 'Tyr-394' residue. Dephosphorylates ZAP70 at its activating 'Tyr-493' residue. Dephosphorylates the immune system activator SKAP2.[2] [3] [4] [5]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
Protein tyrosine phosphatases (PTPs) play a critical role in regulating cellular functions by selectively dephosphorylating their substrates. Here we present 22 human PTP crystal structures that, together with prior structural knowledge, enable a comprehensive analysis of the classical PTP family. Despite their largely conserved fold, surface properties of PTPs are strikingly diverse. A potential secondary substrate-binding pocket is frequently found in phosphatases, and this has implications for both substrate recognition and development of selective inhibitors. Structural comparison identified four diverse catalytic loop (WPD) conformations and suggested a mechanism for loop closure. Enzymatic assays revealed vast differences in PTP catalytic activity and identified PTPD1, PTPD2, and HDPTP as catalytically inert protein phosphatases. We propose a "head-to-toe" dimerization model for RPTPgamma/zeta that is distinct from the "inhibitory wedge" model and that provides a molecular basis for inhibitory regulation. This phosphatome resource gives an expanded insight into intrafamily PTP diversity, catalytic activity, substrate recognition, and autoregulatory self-association.
Large-scale structural analysis of the classical human protein tyrosine phosphatome.,Barr AJ, Ugochukwu E, Lee WH, King ON, Filippakopoulos P, Alfano I, Savitsky P, Burgess-Brown NA, Muller S, Knapp S Cell. 2009 Jan 23;136(2):352-63. PMID:19167335[6]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Kyogoku C, Langefeld CD, Ortmann WA, Lee A, Selby S, Carlton VE, Chang M, Ramos P, Baechler EC, Batliwalla FM, Novitzke J, Williams AH, Gillett C, Rodine P, Graham RR, Ardlie KG, Gaffney PM, Moser KL, Petri M, Begovich AB, Gregersen PK, Behrens TW. Genetic association of the R620W polymorphism of protein tyrosine phosphatase PTPN22 with human SLE. Am J Hum Genet. 2004 Sep;75(3):504-7. Epub 2004 Jul 23. PMID:15273934 doi:10.1086/423790
- ↑ Wu J, Katrekar A, Honigberg LA, Smith AM, Conn MT, Tang J, Jeffery D, Mortara K, Sampang J, Williams SR, Buggy J, Clark JM. Identification of substrates of human protein-tyrosine phosphatase PTPN22. J Biol Chem. 2006 Apr 21;281(16):11002-10. Epub 2006 Feb 6. PMID:16461343 doi:10.1074/jbc.M600498200
- ↑ Yu X, Sun JP, He Y, Guo X, Liu S, Zhou B, Hudmon A, Zhang ZY. Structure, inhibitor, and regulatory mechanism of Lyp, a lymphoid-specific tyrosine phosphatase implicated in autoimmune diseases. Proc Natl Acad Sci U S A. 2007 Dec 11;104(50):19767-72. Epub 2007 Dec 3. PMID:18056643 doi:10.1073/pnas.0706233104
- ↑ Barr AJ, Ugochukwu E, Lee WH, King ON, Filippakopoulos P, Alfano I, Savitsky P, Burgess-Brown NA, Muller S, Knapp S. Large-scale structural analysis of the classical human protein tyrosine phosphatome. Cell. 2009 Jan 23;136(2):352-63. PMID:19167335 doi:http://dx.doi.org/10.1016/j.cell.2008.11.038
- ↑ Yu X, Chen M, Zhang S, Yu ZH, Sun JP, Wang L, Liu S, Imasaki T, Takagi Y, Zhang ZY. Substrate Specificity of Lymphoid-specific Tyrosine Phosphatase (Lyp) and Identification of Src Kinase-associated Protein of 55 kDa Homolog (SKAP-HOM) as a Lyp Substrate. J Biol Chem. 2011 Sep 2;286(35):30526-34. Epub 2011 Jun 30. PMID:21719704 doi:10.1074/jbc.M111.254722
- ↑ Barr AJ, Ugochukwu E, Lee WH, King ON, Filippakopoulos P, Alfano I, Savitsky P, Burgess-Brown NA, Muller S, Knapp S. Large-scale structural analysis of the classical human protein tyrosine phosphatome. Cell. 2009 Jan 23;136(2):352-63. PMID:19167335 doi:http://dx.doi.org/10.1016/j.cell.2008.11.038
|
