Protein tyrosine-protein phosphatase required for T-cell activation through the antigen receptor. Acts as a positive regulator of T-cell coactivation upon binding to DPP4. The first PTPase domain has enzymatic activity, while the second one seems to affect the substrate specificity of the first one. Upon T-cell activation, recruits and dephosphorylates SKAP1 and FYN Dephosphorylates LYN, and thereby modulates LYN activity (By similarity)
Tissue Specificity
A synthetic peptide corresponding to residues in the leukocyte common antigen domain of human CD45 was used as immunogen.
Cellular Localization
Membrane; Single-pass type I membrane protein. Membrane raft. Note=Colocalized with DPP4 in membrane rafts