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R-loops as Janus-faced modulators of DNA repair

Nature Cell Biology volume 23, pages 305–313 (2021)Cite this article

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Abstract

R-loops are non-B DNA structures with intriguing dual consequences for gene expression and genome stability. In addition to their recognized roles in triggering DNA double-strand breaks (DSBs), R-loops have recently been demonstrated to accumulate in cis to DSBs, especially those induced in transcriptionally active loci. In this Review, we discuss whether R-loops actively participate in DSB repair or are detrimental by-products that must be removed to avoid genome instability.

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Fig. 1: Current models for RNA–DNA hybrid accumulation in cis to DSBs.
Fig. 2: A function of R-loops in local transcriptional repression.
Fig. 3: Function of R-loops in the successive DSB repair steps.

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Acknowledgements

Funding in G.L.’s laboratory was provided by grants from the European Research Council (ERC-2014-CoG 647344), the Agence Nationale pour la Recherche (ANR-14-CE10-0002-01), the Institut National Contre le Cancer (INCA) and the Ligue Nationale Contre le Cancer (LNCC). We thank S. Egloff (CBI, Toulouse) and D. Lane (CBI, Toulouse) for their critical reading of the manuscript and apologize to colleagues whose work was not cited due to space constraints.

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  1. Molecular, Cellular and Developmental Biology Department (MCD), Centre de Biologie Integrative (CBI), University of Toulouse, CNRS, UPS, Toulouse, France

    Aline Marnef & Gaëlle Legube

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Marnef, A., Legube, G. R-loops as Janus-faced modulators of DNA repair. Nat Cell Biol 23, 305–313 (2021). https://doi.org/10.1038/s41556-021-00663-4

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