The RIF1-Long splice variant promotes G1 phase 53BP1 nuclear bodies to protect against replication stress

  1. Lotte P Watts
  2. Toyoaki Natsume
  3. Yuichiro Saito
  4. Javier Garzon
  5. Qianqian Dong
  6. Lora Boteva
  7. Nick Gilbert
  8. Masato T Kanemaki
  9. Shin-ichiro Hiraga
  10. Anne D Donaldson  Is a corresponding author
  1. University of Aberdeen Institute of Medical Sciences, United Kingdom
  2. National Institute of Genetics, Japan
  3. University of Edinburgh, United Kingdom

Abstract

Human cells lacking RIF1 are highly sensitive to replication inhibitors, but the reasons for this sensitivity have been enigmatic. Here we show that RIF1 must be present both during replication stress and in the ensuing recovery period to promote cell survival. Of two isoforms produced by alternative splicing, we find that RIF1-Long alone can protect cells against replication inhibition, but RIF1-Short is incapable of mediating protection. Consistent with this isoform-specific role, RIF1-Long is required to promote the formation of the 53BP1 nuclear bodies that protect unrepaired damage sites in the G1 phase following replication stress. Overall, our observations show that RIF1 is needed at several cell cycle stages after replication insult, with the RIF1-Long isoform playing a specific role during the ensuing G1 phase in damage site protection.

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. Lotte P Watts

    Institute of Medical Sciences, University of Aberdeen Institute of Medical Sciences, Aberdeen, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  2. Toyoaki Natsume

    Division of Molecular Cell Engineering, National Institute of Genetics, Mishima, Japan
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3544-4491
  3. Yuichiro Saito

    Chromosome Science, National Institute of Genetics, Mishima, Japan
    Competing interests
    The authors declare that no competing interests exist.
  4. Javier Garzon

    Institute of Medical Sciences, University of Aberdeen Institute of Medical Sciences, Aberdeen, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  5. Qianqian Dong

    Institute of Medical Sciences, University of Aberdeen Institute of Medical Sciences, Aberdeen, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  6. Lora Boteva

    Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  7. Nick Gilbert

    Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  8. Masato T Kanemaki

    Department of Chromosome Science,, National Institute of Genetics, Mishima, Japan
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-7657-1649
  9. Shin-ichiro Hiraga

    Institute of Medical Sciences, University of Aberdeen Institute of Medical Sciences, Aberdeen, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  10. Anne D Donaldson

    Institute of Medical Sciences, University of Aberdeen Institute of Medical Sciences, Aberdeen, United Kingdom
    For correspondence
    a.d.donaldson@abdn.ac.uk
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7842-8136

Funding

Cancer Research UK (C1445/A20596)

  • Anne D Donaldson

Cancer Research UK (C1445/A19059)

  • Anne D Donaldson

Japan Society for the Promotion of Science (17K15068)

  • Masato T Kanemaki

Japan Society for the Promotion of Science (18H02170)

  • Masato T Kanemaki

Japan Society for the Promotion of Science (18H04719)

  • Masato T Kanemaki

Medical Research Council (MC_UU_00007/13)

  • Nick Gilbert

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

Reviewing Editor

  1. Raymund J Wellinger, Fac Medecine/Université de Sherbrooke, Canada

Publication history

  1. Received: April 17, 2020
  2. Accepted: November 2, 2020
  3. Accepted Manuscript published: November 3, 2020 (version 1)
  4. Version of Record published: November 17, 2020 (version 2)

Copyright

© 2020, Watts 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. Lotte P Watts
  2. Toyoaki Natsume
  3. Yuichiro Saito
  4. Javier Garzon
  5. Qianqian Dong
  6. Lora Boteva
  7. Nick Gilbert
  8. Masato T Kanemaki
  9. Shin-ichiro Hiraga
  10. Anne D Donaldson
(2020)
The RIF1-Long splice variant promotes G1 phase 53BP1 nuclear bodies to protect against replication stress
eLife 9:e58020.
https://doi.org/10.7554/eLife.58020

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