EBNA 3A

EBNA-3A is a latent viral nuclear protein expressed in EBV transformed lymphoblastic cell lines. It is also found in some immunoblastic lymphomas in vivo. This viral nuclear protein is essential for EBV mediated transformation of B lymphocytes. The EBNA-3A functions as a transcriptional regulator though the target genes are currently unknown. Plays an essential role for activation and immortalization of human B-cells. Represses transcription of viral promoters TP1 and Cp through interaction with host RBPJ, and inhibits EBNA2-mediated activation of these promoters. Since Cp is the promoter for all EBNA mRNAs, EBNA3A probably contributes to a negative autoregulatory control loop