A role for RNA and DNA:RNA hybrids in the modulation of DNA repair by homologous recombination

D'Alessandro, G.; Adamowicz, M.; Whelan, D.; Howard, S. M.; Jones-Weinert, C. W.; Matti, V.; Rothenberg, E.; Cejka, P.; d'Adda di Fagagna, F.

doi:10.1101/255976

bioRxiv · 10.1101/255976

A role for RNA and DNA:RNA hybrids in the modulation of DNA repair by homologous recombination

D'Alessandro, G.·Adamowicz, M.·Whelan, D.·Howard, S. M.·Jones-Weinert, C. W.·Matti, V.·Rothenberg, E.·Cejka, P.·d'Adda di Fagagna, F.

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Abstract

DNA double-strand breaks (DSBs) are toxic DNA lesions which, if not properly repaired, may lead to genomic instability, cell death and senescence. Damage-induced long non-coding RNAs (dilncRNAs) are transcribed from broken DNA ends and contribute to DNA damage response (DDR) signaling. Here we show that dilncRNAs play a role in DSB repair by homologous recombination (HR) by contributing to the recruitment of the HR proteins BRCA1, BRCA2, and RAD51, without affecting DNA-end resection. In S/G2-phase cells, dilncRNAs pair to the resected DNA ends and form DNA:RNA hybrids, which are recognized by BRCA1 and promote its recruitment to DSBs. We also show that RNase H2 is in a complex with the HR proteins BRCA1, PALB2, BRCA2, and RAD51, and that it localizes to DSBs in the S/G2 cell-cycle phase. BRCA2 controls DNA:RNA hybrid levels at DSBs by mediating RNase H2 recruitment and, therefore, hybrids degradation. These results demonstrate that regulated DNA:RNA hybrid levels at DSBs contribute to HR-mediated repair.

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D'Alessandro, G., Adamowicz, M., Whelan, D., Howard, S. M., Jones-Weinert, C. W., Matti, V., Rothenberg, E., Cejka, P., d'Adda di Fagagna, F.. 2018-01-29. A role for RNA and DNA:RNA hybrids in the modulation of DNA repair by homologous recombination. https://doi.org/10.1101/255976

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