This protein binds the cAMP response element (CRE) (consensus: 5′-GTGACGT[AC][AG]-3′), a sequence present in many viral and cellular promoters. Represses transcription from promoters with ATF sites. It may repress transcription by stabilizing the binding of inhibitory cofactors at the promoter. ; [Isoform 2]: Activates transcription presumably by sequestering inhibitory cofactors away from the promoters. ; [Isoform 3]: Stress-induced isoform, counteracts the transcriptional repression of isoform 1.
