Protein tyrosine phosphatase, non-receptor type 1 (PTPN1) is the first member of protein tyrosine phosphatase (PTP) family to be identified. The members of this family are involved in cell growth, differentiation and mitosis. PTPN1 dephosphorylates insulin receptor, JAK2 and TYK2 kinases and negatively regulates cell signaling mediated by these proteins.
