Redox regulation of PTEN and protein tyrosine phosphatases in H2O2-mediated cell signaling

Abstract Protein tyrosine phosphatase (PTP) is a family of enzymes important for regulating cellular phosphorylation state. The oxidation and consequent inactivation of several PTPs by H 2 O 2 are well demonstrated. It is also shown that recovery of enzymatic activity depends on the availability of cellular reductants. Among these redox-regulated PTPs, PTEN, Cdc25 and low molecular weight PTP are known to form a disulfide bond between two cysteines, one in the active site and the other nearby, during oxidation by H 2 O 2 . The disulfide bond likely confers efficiency in the redox regulation of the PTPs and protects cysteine-sulfenic acid of PTPs from further oxidation. In this review, through a comparative analysis of the oxidation process of Yap1 and PTPs, we propose the mechanism of disulfide bond formation in the PTPs.