1. Chromosomes and Gene Expression
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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
Research Article
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Cite this article as: eLife 2020;9:e60000 doi: 10.7554/eLife.60000


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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Article and author information

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
    Competing interests
    Raymund J Wellinger, Reviewing editor, eLife.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-6670-2759


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.

Reviewing Editor

  1. Andrés Aguilera, CABIMER, Universidad de Sevilla, Spain

Publication history

  1. Received: June 14, 2020
  2. Accepted: October 22, 2020
  3. Accepted Manuscript published: October 23, 2020 (version 1)
  4. Version of Record published: November 5, 2020 (version 2)


© 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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