Tyrosine Phosphatases (protein tyrosine phosphatase, PTP)

The PTP family of enzymes has at least 40 known members. Some have properties of transmembrane receptor proteins (RPTP) and the cytosolic forms have a characteristic ca. 240-amino acid catalytic domain. Each PTP has also a phosphate-binding, 11-residue motif containing catalytically active Cys and Arg. The proteins have critical roles in signal transduction relevant to growth, immune response, proliferation, and differentiation. Dimerization negatively regulates the activity of receptor tyrosine phosphatase-α. signal transduction, PTK, synaps; Stetak A et al 2001 Biochem Biophys Res Commun 288:564; substrates: Tiganis T, Bennett AM 2007 Biochem J 402:1; Liu Y et al 2007 Nature Rev Immunol 7:202.