The p48 subunit of the damaged-DNA binding protein DDB associates with theCBP/p300 family of histone acetyltransferase

DDB has been implicated in DNA repair as well as transcription. Mutations i n DDB have been correlated with the repair-deficiency disease, xeroderma pi gmentosum group E (XP-E). The XP-E cells exhibit deficiencies in global gen omic repair, suggesting a role for DDB in that process. DDB also possesses a transcription stimulatory activity. We showed that DDB could function as a transcriptional partner of E2F1. But the mechanism by which DDB stimulate s E2F-regulated transcription or carry out its DNA repair function is not u nderstood. To investigate the mechanisms, we looked for nuclear proteins th at interact with DDB. Here we show that DDB associates with the CBP/p300 fa mily of proteins, in vivo and in vitro. We suggest that DDB participates in global genomic repair by recruiting CBP/p300 to the damaged-chromatin. It is possible that the histone acetyltransferase activities of the CBP/p300 p roteins induce chromatin remodeling at the damaged-sites to allow recruitme nt of the repair complexes. The observation offers insights into both trans cription and repair functions of DDB. (C) 2001 Elsevier Science B.V. All ri ghts reserved.