Transcriptional regulator, potentially with dual roles in transcription initiation and termination. ; [Isoform 1]: Binds DNA and functions as a transcriptional activator (PubMed:12270922). Binds to two G/A-rich sites, ME1a1 and ME1a2, within the MYC promoter having greater affinity for the former (PubMed:1502157). Also binds to multiple G/C-rich sites within the promoter of the Sp1 family of transcription factors (PubMed:1502157). ; [Isoform 2]: Binds DNA and functions as a transcriptional activator (PubMed:12270922). Inhibits MAZ isoform 1-mediated transcription (PubMed:12270922). ; [Isoform 3]: Binds DNA and functions as a transcriptional activator.
