UCSD MOLECULE PAGES Tyrosine-protein phosphatase non-receptor type 2

TC-PTP is a ubiquitous non-receptor type protein tyrosine phosphatase that shows highest expression in hematopoietic tissues. It regulates many signal transduction pathways in hematopoietic as well as non-hematopoietic cells. TCPTP has two splice variants, an endoplasmic reticulum-localized TC48, and predominantly nuclear TC45. Upon various stress conditions and insulin stimuli, TC45 comes out of the nucleus and shuttles between the nucleus and the cytoplasm. TC48 also traffics from the ER to the ERGIC and Golgi and back to the ER. Many receptor tyrosine kinases such as EGF receptor, insulin receptor and Met-receptor are substrates of both the TC-PTP isoforms. TC48 and TC45 have unique interacting partners and substrates as well.