Identification of human TFIID components and direct interaction between a 250-dKa polypeptide and the TATA box-binding protein (TFIID-tau)

Transcription initiation factor IID (TFIID) is composed of a TATA-binding subunit, TBP, and other polypeptides which may be involved for promoter interactions and activator-dependent transcription. Using a TBP-specific antibody column, a number of human TFIID polypeptides which are associated with TBP were isolated. Further characterization of these polypeptides demonstrated that at least one of them could interact directly with TBP. These polypeptides may play a major role in the assembly and function of TFIID.