1. Chromosomes and Gene Expression

Telomerase biogenesis requires a novel Mex67 function and a cytoplasmic association with the Sm7 complex

  1. Yulia Vasianovich
  2. Emmanuel Bajon
  3. Raymund J Wellinger  Is a corresponding author
  1. Fac Medecine/Université de Sherbrooke, Canada
https://doi.org/10.7554/eLife.60000
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  1. Yulia Vasianovich
  2. Emmanuel Bajon
  3. Raymund J Wellinger
(2020)
Telomerase biogenesis requires a novel Mex67 function and a cytoplasmic association with the Sm7 complex
eLife 9:e60000.
https://doi.org/10.7554/eLife.60000
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Abstract

The templating RNA is the core of the telomerase reverse transcriptase. In Saccharomyces cerevisiae, the complex life cycle and maturation of telomerase includes a cytoplasmic stage. However, timing and reason for this cytoplasmic passage are poorly understood. Here, we use inducible RNA tagging experiments to show that immediately after transcription, newly synthesized telomerase RNAs undergo one round of nucleo-cytoplasmic shuttling. Their export depends entirely on Crm1/Xpo1, whereas re-import is mediated by Kap122 plus redundant, kinetically less efficient import pathways. Strikingly, Mex67 is essential to stabilize newly transcribed RNA before Xpo1-mediated nuclear export. The results further show that the Sm7 complex associates with and stabilizes the telomerase RNA in the cytoplasm and promotes its nuclear re-import. Remarkably, after this cytoplasmic passage, the nuclear stability of telomerase RNA no longer depends on Mex67. These results underscore the utility of inducible RNA tagging and challenge current models of telomerase maturation.

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Source data files have been uploaded. Strains and materials generated for this study will be freely available.

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Author details

  1. Yulia Vasianovich

    Dept of Microbiology and Infectious Diseases, Fac Medecine/Université de Sherbrooke, Sherbrooke, Canada
    Competing interests
    No competing interests declared.

  2. Emmanuel Bajon

    Dept of Microbiology and Infectious Diseases, Fac Medecine/Université de Sherbrooke, Sherbrooke, Canada
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-1588-2953

  3. Raymund J Wellinger

    Dept of Microbiology and Infectious Diseases, Fac Medecine/Université de Sherbrooke, Sherbrooke, Canada
    For correspondence
    Raymund.Wellinger@Usherbrooke.ca
    Competing interests
    Raymund J Wellinger, Reviewing editor, eLife.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-6670-2759

Funding

Canada Research Chairs (CRC in telomere biology)

  • Raymund J Wellinger

Canadian Institutes of Health Research (FDN154315)

  • Raymund J Wellinger

Fonds de Recherche du Québec - Santé (Post-Doc Fellowship)

  • Yulia Vasianovich

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

Copyright

© 2020, Vasianovich 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. Yulia Vasianovich
  2. Emmanuel Bajon
  3. Raymund J Wellinger
(2020)
Telomerase biogenesis requires a novel Mex67 function and a cytoplasmic association with the Sm7 complex
eLife 9:e60000.
https://doi.org/10.7554/eLife.60000

Share this article

https://doi.org/10.7554/eLife.60000

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