Structural highlights
Function
PTN1_HUMAN Tyrosine-protein phosphatase which acts as a regulator of endoplasmic reticulum unfolded protein response. Mediates dephosphorylation of EIF2AK3/PERK; inactivating the protein kinase activity of EIF2AK3/PERK. May play an important role in CKII- and p60c-src-induced signal transduction cascades. May regulate the EFNA5-EPHA3 signaling pathway which modulates cell reorganization and cell-cell repulsion.[1] [2]
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
The second messenger hydrogen peroxide is required for optimal activation of numerous signal transduction pathways, particularly those mediated by protein tyrosine kinases. One mechanism by which hydrogen peroxide regulates cellular processes is the transient inhibition of protein tyrosine phosphatases through the reversible oxidization of their catalytic cysteine, which suppresses protein dephosphorylation. Here we describe a structural analysis of the redox-dependent regulation of protein tyrosine phosphatase 1B (PTP1B), which is reversibly inhibited by oxidation after cells are stimulated with insulin and epidermal growth factor. The sulphenic acid intermediate produced in response to PTP1B oxidation is rapidly converted into a previously unknown sulphenyl-amide species, in which the sulphur atom of the catalytic cysteine is covalently linked to the main chain nitrogen of an adjacent residue. Oxidation of PTP1B to the sulphenyl-amide form is accompanied by large conformational changes in the catalytic site that inhibit substrate binding. We propose that this unusual protein modification both protects the active-site cysteine residue of PTP1B from irreversible oxidation to sulphonic acid and permits redox regulation of the enzyme by promoting its reversible reduction by thiols.
Redox regulation of protein tyrosine phosphatase 1B involves a sulphenyl-amide intermediate.,Salmeen A, Andersen JN, Myers MP, Meng TC, Hinks JA, Tonks NK, Barford D Nature. 2003 Jun 12;423(6941):769-73. PMID:12802338[3]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Nievergall E, Janes PW, Stegmayer C, Vail ME, Haj FG, Teng SW, Neel BG, Bastiaens PI, Lackmann M. PTP1B regulates Eph receptor function and trafficking. J Cell Biol. 2010 Dec 13;191(6):1189-203. doi: 10.1083/jcb.201005035. Epub 2010, Dec 6. PMID:21135139 doi:10.1083/jcb.201005035
- ↑ Krishnan N, Fu C, Pappin DJ, Tonks NK. H2S-Induced sulfhydration of the phosphatase PTP1B and its role in the endoplasmic reticulum stress response. Sci Signal. 2011 Dec 13;4(203):ra86. doi: 10.1126/scisignal.2002329. PMID:22169477 doi:10.1126/scisignal.2002329
- ↑ Salmeen A, Andersen JN, Myers MP, Meng TC, Hinks JA, Tonks NK, Barford D. Redox regulation of protein tyrosine phosphatase 1B involves a sulphenyl-amide intermediate. Nature. 2003 Jun 12;423(6941):769-73. PMID:12802338 doi:10.1038/nature01680
