Identification of a BRCA1-mRNA splicing complex required for efficient DNA repair and maintenance of genomic stability.
Savage KI., Gorski JJ., Barros EM., Irwin GW., Manti L., Powell AJ., Pellagatti A., Lukashchuk N., McCance DJ., McCluggage WG., Schettino G., Salto-Tellez M., Boultwood J., Richard DJ., McDade SS., Harkin DP.
Mutations within BRCA1 predispose carriers to a high risk of breast and ovarian cancers. BRCA1 functions to maintain genomic stability through the assembly of multiple protein complexes involved in DNA repair, cell-cycle arrest, and transcriptional regulation. Here, we report the identification of a DNA damage-induced BRCA1 protein complex containing BCLAF1 and other key components of the mRNA-splicing machinery. In response to DNA damage, this complex regulates pre-mRNA splicing of a number of genes involved in DNA damage signaling and repair, thereby promoting the stability of these transcripts/proteins. Further, we show that abrogation of this complex results in sensitivity to DNA damage, defective DNA repair, and genomic instability. Interestingly, mutations in a number of proteins found within this complex have been identified in numerous cancer types. These data suggest that regulation of splicing by the BRCA1-mRNA splicing complex plays an important role in the cellular response to DNA damage.