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DNA–RNA hybrids: the risks of DNA breakage during transcription

Nature Structural & Molecular Biology volume 24, pages 439–443 (2017)Cite this article

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Abstract

Although R loops can occur at different genomic locations, the factors that determine their formation and frequency remain unclear. Emerging evidence indicates that DNA breaks stimulate DNA–RNA hybrid formation. Here, we discuss the possibility that formation of hybrids may be an inevitable risk of DNA breaks that occur within actively transcribed regions. While such hybrids must be removed to permit repair, their potential role as repair intermediates remains to be established.

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Figure 1: Multiple protein factors act at three distinct steps to prevent harmful DNA–RNA hybrid accumulation.
Figure 2: Structural features that stimulate DNA–RNA hybrid formation along transcribed DNA.
Figure 3: Potential impact of DNA–RNA hybrids on DNA double-strand break repair.

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Acknowledgements

We thank D. Haun for style correction. Research in A.A.'s lab is funded by the European Research Council, Spanish Ministry of Economy and Competitiveness, Junta de Andalucía and Worldwide Cancer Research. B.G.-G. is a postdoctoral fellow of the Scientific Foundation of the Spanish Association Against Cancer (AECC).

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  1. Centro Andaluz de Biología Molecular y Medicina Regenerativa (CABIMER), Universidad de Sevilla-CSIC-Universidad Pablo de Olavide, Seville, Spain

    Andrés Aguilera & Belén Gómez-González

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  2. Belén Gómez-González
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Correspondence to Andrés Aguilera.

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Aguilera, A., Gómez-González, B. DNA–RNA hybrids: the risks of DNA breakage during transcription. Nat Struct Mol Biol 24, 439–443 (2017). https://doi.org/10.1038/nsmb.3395

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