DNA-binding transcriptional activator proteins increase the rate of transcription by interacting with the transcriptional machinery bound to the basal promoter in conjunction with adaptor proteins, possibly by acetylation and destabilization of nucleosomes. The protein encoded by this gene is a transcriptional activator adaptor and a component of the histone acetyl transferase (HAT) coactivator complex which plays a crucial role in chromatin modulation and cell cycle progression. Along with the other components of the complex, this protein links transcriptional activators bound to specific promoters, to histone acetylation and the transcriptional machinery. The protein is also involved in the stabilization and activation of the p53 tumor suppressor protein that plays a role in the cellular response to DNA damage. Alternate splicing results in multiple transcript variants of this gene.