title: CBP and p300 histone acetyltransferases contribute to homologous recombination by transcriptionally activating the BRCA1 and RAD51 genes.
abstract: Histone acetylation at DNA double-strand break (DSB) sites by CBP and p300 histone acetyltransferases (HATs) is critical for the recruitment of DSB repair proteins to chromatin. Here, we show that CBP and p300 HATs also function in DSB repair by transcriptionally activating the BRCA1 and RAD51 genes, which are involved in homologous recombination (HR), a major DSB repair system. siRNA-mediated depletion of CBP and p300 impaired HR activity and downregulated BRCA1 and RAD51 at the protein and mRNA levels. Chromatin immunoprecipitation assays showed that CBP and p300 bind to the promoter regions of the BRCA1 and RAD51 genes, and that depletion of CBP and/or p300 reduces H3 and H4 acetylation and inhibits binding of the transcription factor E2F1 to these promoters. Depletion of CBP and p300 impaired DNA damage-induced phosphorylation and chromatin binding of the single-strand DNA-binding protein RPA following BRCA1-mediated DNA end resection. Consistent with this, subsequent phosphorylation of CHK1 and activation of the G2/M damage checkpoint were also impaired. These results indicate that the HATs CBP and p300 play multiple roles in the activation of the cellular response to DSBs.
authors.affiliation: Division of Genome Biology, National Cancer Center Research Institute, Chuo-ku, Tokyo, Japan.
authors.forename: Hideaki
authors.initials: H
authors.lastname: Ogiwara
authors.forename: Takashi
authors.initials: T
authors.lastname: Kohno
mesh_terms: D000107:Acetylation; D019313:BRCA1 Protein / Q000235:genetics*; D050882:CREB-Binding Protein / Q000378:metabolism*; D045744:Cell Line, Tumor; D000071877:Checkpoint Kinase 1; D053903:DNA Breaks, Double-Stranded; D050687:E2F1 Transcription Factor; D015972:Gene Expression Regulation, Neoplastic; D006657:Histones / Q000378:metabolism; D059765:Homologous Recombination; D006801:Humans; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D011494:Protein Kinases / Q000378:metabolism; D051135:Rad51 Recombinase / Q000235:genetics*; D051716:Replication Protein A / Q000378:metabolism; D015398:Signal Transduction; D015533:Transcriptional Activation; D050880:p300-CBP Transcription Factors / Q000378:metabolism*; D000099224:p300-CBP-Associated Factor
chemical_list: D019313:BRCA1 Protein; D050882:CREB-Binding Protein; D000071877:Checkpoint Kinase 1; D050687:E2F1 Transcription Factor; D006657:Histones; D011494:Protein Kinases; D051135:Rad51 Recombinase; D051716:Replication Protein A; D050880:p300-CBP Transcription Factors; D000099224:p300-CBP-Associated Factor; C000605867:CHEK1 protein, human