1. Chromosomes and Gene Expression
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Factors affecting template switch recombination associated with restarted DNA replication

  1. Manisha Jalan
  2. Judith Oehler
  3. Carl A Morrow
  4. Fekret Osman
  5. Matthew C Whitby  Is a corresponding author
  1. University of Oxford, United Kingdom
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  • Views 2,130
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Cite this article as: eLife 2019;8:e41697 doi: 10.7554/eLife.41697

Abstract

Homologous recombination helps ensure the timely completion of genome duplication by restarting collapsed replication forks. This beneficial function is not without risk however, as replication restarted by homologous recombination is prone to template switching (TS) that can generate deleterious genome rearrangements associated with diseases such as cancer. In a previous paper (Nguyen et al., 2015), we established an assay for studying TS in Schizosaccharomyces pombe. Here, we advance this work by showing that TS is detected up to 75 kb downstream of a collapsed replication fork and can be triggered by head-on collision between the restarted fork and RNA Polymerase III transcription. The Pif1 DNA helicase, Pfh1, promotes efficient restart and also suppresses TS. A further three conserved helicases (Fbh1, Rqh1 and Srs2) strongly suppress TS, but there is no change in TS frequency in cells lacking Fml1 or Mus81. We discuss how these factors likely influence TS.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting files.

Article and author information

Author details

  1. Manisha Jalan

    Department of Biochemistry, University of Oxford, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4467-4934
  2. Judith Oehler

    Department of Biochemistry, University of Oxford, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  3. Carl A Morrow

    Department of Biochemistry, University of Oxford, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  4. Fekret Osman

    Department of Biochemistry, University of Oxford, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  5. Matthew C Whitby

    Department of Biochemistry, University of Oxford, Oxford, United Kingdom
    For correspondence
    matthew.whitby@bioch.ox.ac.uk
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0951-3374

Funding

Wellcome (090767/Z/09/Z)

  • Matthew C Whitby

Medical Research Council (MR/P028292/1)

  • Matthew C Whitby

Biotechnology and Biological Sciences Research Council (BB/P019706/1)

  • Matthew C Whitby

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

Reviewing Editor

  1. Michael Lisby, University of Copenhagen, Denmark

Publication history

  1. Received: September 5, 2018
  2. Accepted: January 21, 2019
  3. Accepted Manuscript published: January 22, 2019 (version 1)
  4. Version of Record published: February 1, 2019 (version 2)

Copyright

© 2019, Jalan 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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