PCNA (Proliferating Cell Nuclear Antigen) is found in the nucleus and is a cofactor of DNA polymerase delta. This protein is associated with DNA synthesis and repair. The encoded protein acts as a homotrimer and helps increase the processivity of leading strand synthesis during DNA replication. It appears during late G1- phase, S-phase of mitosis and persists until the end of the M-phase because of its long biological half-life. PCNA may be induced by UV irradiation, growth factors and eventually by neighbouring tumours. Recombinant human PCNA, was expressed in E.coli and purified by conventional chromatography techniques. Synonyms: MGC8367, Proliferating cell nuclear antigen, Proliferating cell nuclear antigen, PCNA,. NCBI no.: NP_002583