Rif2 protects Rap1-depleted telomeres from MRX-mediated degradation in Saccharomyces cerevisiae

  1. Fernando Rodrigo Rosas Bringas
  2. Sonia Stinus
  3. Pien de Zoeten
  4. Marita Cohn
  5. Michael Chang  Is a corresponding author
  1. University Medical Center Groningen, Netherlands
  2. Lund University, Sweden

Abstract

Rap1 is the main protein that binds double-stranded telomeric DNA in Saccharomyces cerevisiae. Examination of the telomere functions of Rap1 is complicated by the fact that it also acts as a transcriptional regulator of hundreds of genes and is encoded by an essential gene. In this study, we disrupt Rap1 telomere association by expressing a mutant telomerase RNA subunit (tlc1-tm) that introduces mutant telomeric repeats. tlc1-tm cells grow similar to wild-type cells, although depletion of Rap1 at telomeres causes defects in telomere length regulation and telomere capping. Rif2 is a protein normally recruited to telomeres by Rap1, but we show that Rif2 can still associate with Rap1-depleted tlc1-tm telomeres, and that this association is required to inhibit telomere degradation by the MRX complex. Rif2 and the Ku complex work in parallel to prevent tlc1-tm telomere degradation; tlc1-tm cells lacking Rif2 and the Ku complex are inviable. The partially redundant mechanisms may explain the rapid evolution of telomere components in budding yeast species.

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

Article and author information

Author details

  1. Fernando Rodrigo Rosas Bringas

    European Research Institute for the Biology of Ageing, University Medical Center Groningen, Groningen, Netherlands
    Competing interests
    The authors declare that no competing interests exist.
  2. Sonia Stinus

    European Research Institute for the Biology of Ageing, University Medical Center Groningen, Groningen, Netherlands
    Competing interests
    The authors declare that no competing interests exist.
  3. Pien de Zoeten

    European Research Institute for the Biology of Ageing, University Medical Center Groningen, Groningen, Netherlands
    Competing interests
    The authors declare that no competing interests exist.
  4. Marita Cohn

    Department of Biology, Lund University, Lund, Sweden
    Competing interests
    The authors declare that no competing interests exist.
  5. Michael Chang

    European Research Institute for the Biology of Ageing, University Medical Center Groningen, Groningen, Netherlands
    For correspondence
    m.chang@umcg.nl
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-1706-3337

Funding

Nederlandse Organisatie voor Wetenschappelijk Onderzoek (Vidi grant,864.12.002)

  • Michael Chang

Carl Tryggers Stiftelse för Vetenskaplig Forskning

  • Marita Cohn

Erik Philip-Sörensen Foundation

  • Marita Cohn

Royal Physiographic Society of Lund

  • Marita Cohn

Consejo Nacional de Ciencia y Tecnología (PhD scholarship)

  • Fernando Rodrigo Rosas Bringas

European Molecular Biology Organization (Short-Term Fellowship)

  • Sonia Stinus

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

Copyright

© 2022, Rosas Bringas 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. Fernando Rodrigo Rosas Bringas
  2. Sonia Stinus
  3. Pien de Zoeten
  4. Marita Cohn
  5. Michael Chang
(2022)
Rif2 protects Rap1-depleted telomeres from MRX-mediated degradation in Saccharomyces cerevisiae
eLife 11:e74090.
https://doi.org/10.7554/eLife.74090

Share this article

https://doi.org/10.7554/eLife.74090

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