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bioRxiv · 10.1101/2020.04.20.047134

Harmful DNA:RNA hybrids are formed in cis and in a Rad51-independent manner

Aguilera, A.·Gomez-Gonzalez, B.·Lafuente-Barquero, J.·Martin-Alonso, M. S.
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Abstract

DNA:RNA hybrids constitute a well-known source of recombinogenic DNA damage. The current literature is in agreement with DNA:RNA hybrids being produced co-transcriptionally by the invasion of the nascent RNA molecule produced in cis with its DNA template. However, it has also been suggested that recombinogenic DNA:RNA hybrids could be facilitated by the invasion of RNA molecules produced in trans in a Rad51-mediated reaction. Here, we tested the possibility that such DNA:RNA hybrids produced in trans constitute a source of recombinogenic DNA damage taking advantage of Rad51-independent single-strand annealing recombination assays and new constructs designed to induce expression of mRNA transcripts in trans in the yeast Saccharomyces cerevisiae. We show that unscheduled and recombinogenic DNA:RNA hybrids are formed in cis during transcription and in a Rad51-independent manner.

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Aguilera, A., Gomez-Gonzalez, B., Lafuente-Barquero, J., Martin-Alonso, M. S.. 2020-04-21. Harmful DNA:RNA hybrids are formed in cis and in a Rad51-independent manner. https://doi.org/10.1101/2020.04.20.047134

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