catalytic domain of receptor-type tyrosine-protein phosphatase E, repeat 1
Receptor-type tyrosine-protein phosphatase E (PTPRE), also known as receptor-type tyrosine-protein phosphatase epsilon (R-PTP-epsilon), belongs to the family of classical tyrosine-specific protein tyrosine phosphatases (PTPs). PTPs (EC 3.1.3.48) catalyze the dephosphorylation of phosphotyrosine peptides. The PTPRE gene contains two distinct promoters that generate the two major isoforms: transmembrane (receptor type RPTPe or PTPeM) and cytoplasmic (cyt-PTPe or PTPeC). Receptor type RPTPe plays a critical role in signaling transduction pathways and phosphoprotein network topology in red blood cells, and may also play a role in osteoclast formation and function. It also negatively regulates PDGFRbeta-mediated signaling pathways that are crucial for the pathogenesis of atherosclerosis. cyt-PTPe acts as a negative regulator of insulin receptor signaling in skeletal muscle. It regulates insulin-induced phosphorylation of proteins downstream of the insulin receptor. Receptor type RPTPe contains a small extracellular region, a single transmembrane segment, and an intracellular region two tandem catalytic PTP domains. This model represents the first 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