The adenovirus DNA-binding protein stimulates the rate of transcription directed by adenovirus and adeno-associated virus promoters

The DNA-binding protein (DBP) encoded by the E2A region of adenovirus type 5 was found to enhance the expression of a reporter gene controlled by several different promoters within transfected cells. The rate of synthesis of correctly initiated transcripts was increased by the DBP. The adeno-associated virus P5 promoter and the adenovirus E1A and E2A early and major late promoters responded to the DBP by increases in expression ranging from 6- to 27-fold, while the adenovirus E4 promoter was slightly inhibited by DBP. The adenovirus major late promoter showed a greater response to DBP than to the E1A transactivator protein, suggesting that the DBP plays a central role in activation of the late promoter.