A novel function of the transforming domain of E1a : repression of AP-1 activity

Abstract Adenovirus E1a represses transcription of the collagenase gene via the phorbol ester-responsive element (collTRE). The mechanism involves inhibition of the trans -activating function of the transcription factor AP-1 without reduction of its synthesis and without any apparent change in DNA binding or composition. The ability of E1a to downmodulate AP-1 is a unique property among dominant oncogenes. This repression depends on conserved region 1, one of the transforming domains of E1a, indicating that it is an integral feature of adenovirus transformation.