1oet
OXIDATION STATE OF PROTEIN TYROSINE PHOSPHATASE 1B
|
OverviewOverview
Protein tyrosine phosphatases regulate signal transduction pathways, involving tyrosine phosphorylation and have been implicated in the, development of cancer, diabetes, rheumatoid arthritis and hypertension., Increasing evidence suggests that the cellular redox state is involved in, regulating tyrosine phosphatase activity through the reversible, oxidization of the catalytic cysteine to sulphenic acid (Cys-SOH). But how, further oxidation to the irreversible sulphinic (Cys-SO2H) and sulphonic, (Cys-SO3H) forms is prevented remains unclear. Here we report the crystal, structures of the regulatory sulphenic and irreversible sulphinic and, sulphonic acids of protein tyrosine phosphatase 1B (PTP1B), an important, enzyme in the negative regulation of the insulin receptor and a, therapeutic target in type II diabetes and obesity. We also identify a, sulphenyl-amide species that is formed through oxidation of its catalytic, cysteine. Formation of the sulphenyl-amide causes large changes in the, PTP1B active site, which are reversible by reduction with the cellular, reducing agent glutathione. The sulphenyl-amide is a protective, intermediate in the oxidative inhibition of PTP1B. In addition, it may, facilitate reactivation of PTP1B by biological thiols and signal a unique, state of the protein.
DiseaseDisease
Known diseases associated with this structure: Abdominal body fat distribution, modifier of OMIM:[176885], Insulin resistance, susceptibility to OMIM:[176885]
About this StructureAbout this Structure
1OET is a Single protein structure of sequence from Homo sapiens with MG as ligand. Active as Protein-tyrosine-phosphatase, with EC number 3.1.3.48 Known structural/functional Site: . Full crystallographic information is available from OCA.
ReferenceReference
Oxidation state of the active-site cysteine in protein tyrosine phosphatase 1B., van Montfort RL, Congreve M, Tisi D, Carr R, Jhoti H, Nature. 2003 Jun 12;423(6941):773-7. PMID:12802339
Page seeded by OCA on Tue Dec 18 17:39:06 2007