catalytic domain of receptor-type tyrosine-protein phosphatase A, repeat 1
Receptor-type tyrosine-protein phosphatase A (PTPRA), also known as receptor-type tyrosine-protein phosphatase alpha (R-PTP-alpha), belongs to the family of classical tyrosine-specific protein tyrosine phosphatases (PTPs). PTPs (EC 3.1.3.48) catalyze the dephosphorylation of phosphotyrosine peptides. PTPRA is a positive regulator of Src and Src family kinases via dephosphorylation of the Src-inhibitory tyrosine 527. Thus, it affects transformation and tumorigenesis, inhibition of proliferation, cell cycle arrest, integrin signaling, neuronal differentiation and outgrowth, and ion channel activity. It is also involved in interleukin-1 signaling in fibroblasts through its interaction with the focal adhesion targeting domain of focal adhesion kinase. PTPRA comprises a small extracellular domain, a transmembrane segment, and an intracellular region containing two tandem catalytic PTP domains. This model represents the first catalytic PTP domain (repeat 1).
Feature 1: catalytic site [active site], 2 residue positions
Conserved feature residue pattern:C R
Evidence:
Comment:the catalytic cysteine initiates a nucleophilic attack on the phosphate group of the substrate, forming a transient phosphoenzyme intermediate and releasing the substrate dephosphorylated; the transition state is stabilized by the arginine present in the catalytic pocket