Harmful DNA:RNA hybrids are formed in cis and in a Rad51-independent manner
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 constitute a source of recombinogenic DNA damage taking advantage of Rad51-independent single-strand annealing (SSA) assays in the yeast Saccharomyces cerevisiae. For this, we used new constructs designed to induce expression of mRNA transcripts in trans with respect to the SSA system. We show that unscheduled and recombinogenic DNA:RNA hybrids that trigger the SSA event are formed in cis during transcription and in a Rad51-independent manner. We found no evidence that such hybrids form in trans and in a Rad51-dependent manner.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for all graphs.
Article and author information
Author details
Funding
Ministerio de Economía y Competitividad (BFU2016-75058-P)
- Andrés Aguilera
European Union
- Andrés Aguilera
Spanish Association Against Cancer
- Belén Gómez-González
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Wolf-Dietrich Heyer, University of California, Davis, United States
Version history
- Received: March 5, 2020
- Accepted: August 3, 2020
- Accepted Manuscript published: August 4, 2020 (version 1)
- Version of Record published: August 17, 2020 (version 2)
Copyright
© 2020, Lafuente-Barquero et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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