SERTA domain-containing protein (SERTAD1) functions with E2F-responsive promoters to integrate signals provided by PHD- and/or bromodomain-containing transcription factors. SERTAD1 stimulates E2F-1/DP-1 transcriptional activity. SERTAD1 reduces the activity of cyclin D1/CDK4 resistant to the inhibitory effects of p16(INK4a). In addition, SERTAD1 interacts with the PHD-bromodomain of TIF1, TRIM28/TIF1B and p300/CBP. Furthermore, SERTAD1 binds to DP1 and interacts with CDK4.