E1A-dependent trans-activation of the human MYC promoter is mediated by the E2F factor

E2F is a cellular transcription factor that binds to two sites in the adenovirus E2 promoter. Previous experiments have implicated E2F in the E1A-dependent transactivation of the E2 gene since levels of active E2F increase markedly during adenovirus infection in parallel with the increase in E2 transcription, and an E2F binding site can confer E1A inducibility to a heterologous promoter. Here we show that E2F binds to two sequence elements within the P2 promoter of the human MYC gene which are within a region that is critical for promoter activity. The MYC promoter can be trans-activated in an E1A-dependent manner and site-directed mutagenesis demonstrates that these E2F elements are essential for trans-activation. Finally, we also find that adenovirus infection of quiescent cells results in a stimulation of the endogenous MYC gene. We conclude that the activation of the E2F factor, which is likely responsible for the activation of viral E2 transcription, is also responsible for the E1A-dependent induction of MYC transcription.