Rif2 protects Rap1-depleted telomeres from MRX-mediated degradation in Saccharomyces cerevisiae
- University Medical Center Groningen, Netherlands
- 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.
Data availability
All data generated or analysed during this study are included in the manuscript and source data files.
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Author details
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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Rif2 protects Rap1-depleted telomeres from MRX-mediated degradation in Saccharomyces cerevisiae
eLife 11:e74090.
https://doi.org/10.7554/eLife.74090
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