Rat Receptor-Type Tyrosine-Protein Phosphatase C / CD45 (PTPRC) Protein

Background

PTPRC, also known as CD45, is a receptor-type tyrosine phosphatase primarily expressed in hematopoietic cells. It regulates antigen receptor signaling in lymphocytes by dephosphorylating inhibitory residues on Src family kinases such as Lck and Fyn. Structurally, PTPRC has an extracellular domain, a single transmembrane region, and two cytoplasmic phosphatase domains, with the first being catalytically active. It is critical for T-cell and B-cell activation, development, and immune response regulation. Mutations in PTPRC are linked to severe immunodeficiency disorders, including SCID, and its overexpression is associated with autoimmune diseases and leukemia.