3sme
From Proteopedia
Structure of PTP1B inactivated by H2O2/bicarbonate
Structural highlights
FunctionPTN1_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] Publication Abstract from PubMedHydrogen peroxide is a cell signaling agent that inactivates protein tyrosine phosphatases (PTPs) via oxidation of their catalytic cysteine residue. PTPs are inactivated rapidly during H(2)O(2)-mediated cellular signal transduction processes, but, paradoxically, hydrogen peroxide is a rather sluggish PTP inactivator in vitro. Here we present evidence that the biological buffer bicarbonate/CO(2) potentiates the ability of H(2)O(2) to inactivate PTPs. The results of biochemical experiments and high-resolution crystallographic analysis are consistent with a mechanism involving oxidation of the catalytic cysteine residue by peroxymonocarbonate generated via the reaction of H(2)O(2) with HCO(3)(-)/CO(2). The Biological Buffer Bicarbonate/CO(2) Potentiates H(2)O(2)-Mediated Inactivation of Protein Tyrosine Phosphatases.,Zhou H, Singh H, Parsons ZD, Lewis SM, Bhattacharya S, Seiner DR, Labutti JN, Reilly TJ, Tanner JJ, Gates KS J Am Chem Soc. 2011 Oct 12;133(40):15803-5. Epub 2011 Sep 19. PMID:21913686[3] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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