HUMAN TAF(II)31 PROTEIN IS A TRANSCRIPTIONAL COACTIVATOR OF THE P53 PROTEIN

The p53 protein activates transcription of a target gene by binding to a specific DNA response element and interacting with the transcriptional apparatus of RNA polymerase II. The amino-terminal domain of p53 interacts with a component of the TFIID basal transcription complex. The human TATA-binding-protein-associated factor TAF(II)31, a component of TFIID, has been identified as a critical protein required for p53-mediated transcriptional activation. TAF(II)31 and p53 proteins bind to each other via amino acid residues in the amino-terminal domain of p53 that are essential for transcription. Antibodies directed against TAF(II)31 protein inhibit p53-activated but not basal transcription in vitro. These results demonstrate that TAF(II)31 is a coactivator for the p53 protein.