1. Cell Biology
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A novel checkpoint pathway controls actomyosin ring constriction trigger in fission yeast

  1. Tomás Edreira
  2. Rubén Celador
  3. Elvira Manjón
  4. Yolanda Sánchez  Is a corresponding author
  1. Universidad de Salamanca, Spain
Research Article
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Cite this article as: eLife 2020;9:e59333 doi: 10.7554/eLife.59333


In fission yeast, the septation initiation network (SIN) ensures temporal coordination between actomyosin ring (CAR) constriction with membrane ingression and septum synthesis. However, questions remain about CAR regulation under stress conditions. We show that Rgf1p (Rho1p GEF), participates in a delay of cytokinesis under cell wall stress (blankophor, BP). BP did not interfere with CAR assembly or the rate of CAR constriction, but did delay the onset of constriction in the wild type cells but not in the rgf1Δ cells. This delay was also abolished in the absence of Pmk1p, the MAPK of the cell integrity pathway (CIP), leading to premature abscission and a multi-septated phenotype. Moreover, cytokinesis delay correlates with maintained SIN signaling and depends on the SIN to be achieved. Thus, we propose that the CIP participates in a checkpoint, capable of triggering a CAR constriction delay through the SIN pathway to ensure that cytokinesis terminates successfully.

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

Article and author information

Author details

  1. Tomás Edreira

    Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
    Competing interests
    The authors declare that no competing interests exist.
  2. Rubén Celador

    Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
    Competing interests
    The authors declare that no competing interests exist.
  3. Elvira Manjón

    Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
    Competing interests
    The authors declare that no competing interests exist.
  4. Yolanda Sánchez

    Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
    For correspondence
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-7650-9319


Regional Governmen of Castile and Leon co-financed by the European Social Fund

  • Tomás Edreira
  • Elvira Manjón

University of Salamanca

  • Rubén Celador

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

Reviewing Editor

  1. Mohan K Balasubramanian, University of Warwick, United Kingdom

Publication history

  1. Received: May 26, 2020
  2. Accepted: October 24, 2020
  3. Accepted Manuscript published: October 26, 2020 (version 1)
  4. Version of Record published: November 12, 2020 (version 2)


© 2020, Edreira 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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