| Background | SV40 T antigen is encoded by the early region of the SV40 genome. The large T antigen binds DNA, and complexes with a 53,000 dalton cellular protein, p53, which is required for initiation of viral DNA replication during lytic growth. In addition the large T antigen binds DNA polymerase and the transcription factor AP-2 and forms a specific complex with the P105 product of the retinoblastoma susceptibility gene. |