High-resolution mapping of heteroduplex DNA formed during UV-induced and spontaneous mitotic recombination events in yeast

  1. Yi Yin
  2. Margaret Dominska
  3. Eunice Yim
  4. Thomas D Petes  Is a corresponding author
  1. University of Washington, United States
  2. Duke University Medical Center, United States

Abstract

In yeast, DNA breaks are usually repaired by homologous recombination (HR). An early step for HR pathways is formation of a heteroduplex, in which a single-strand from the broken DNA molecule pairs with a strand derived from an intact DNA molecule. If the two strands of DNA are not identical, there will be mismatches within the heteroduplex DNA (hetDNA). In wild-type strains, these mismatches are repaired by the mismatch repair (MMR) system, producing a gene conversion event. In strains lacking MMR, the mismatches persist. Most previous studies involving hetDNA formed during mitotic recombination were restricted to one locus. Below, we present a global mapping of hetDNA formed in the MMR-defective mlh1 strain. We find that many recombination events are associated with repair of double-stranded DNA gaps and/or involve Mlh1-independent mismatch repair. Many of our events are not explicable by the simplest form of the double-strand break repair model of recombination.

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Author details

  1. Yi Yin

    Department of Genome Sciences, University of Washington, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0963-2672
  2. Margaret Dominska

    Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Eunice Yim

    Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Thomas D Petes

    Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, United States
    For correspondence
    tom.petes@duke.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4890-8002

Funding

National Institute of General Medical Sciences (GM24110)

  • Yi Yin
  • Margaret Dominska
  • Eunice Yim
  • Thomas D Petes

National Institute of General Medical Sciences (GM52319)

  • Yi Yin
  • Margaret Dominska
  • Eunice Yim
  • Thomas D Petes

National Institute of General Medical Sciences (1R35GM118020)

  • Yi Yin
  • Margaret Dominska
  • Eunice Yim
  • Thomas D Petes

National Institute of General Medical Sciences (5T32GM007754-37)

  • Yi Yin
  • Margaret Dominska
  • Eunice Yim
  • Thomas D Petes

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Copyright

© 2017, Yin 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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  1. Yi Yin
  2. Margaret Dominska
  3. Eunice Yim
  4. Thomas D Petes
(2017)
High-resolution mapping of heteroduplex DNA formed during UV-induced and spontaneous mitotic recombination events in yeast
eLife 6:e28069.
https://doi.org/10.7554/eLife.28069

Share this article

https://doi.org/10.7554/eLife.28069

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