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Protein Phosphatase 1 in association with Bud14 inhibits mitotic exit in Saccharomyces cerevisiae

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Cite this article as: eLife 2021;10:e72833 doi: 10.7554/eLife.72833

Abstract

Mitotic exit in budding yeast is dependent on correct orientation of the mitotic spindle along the cell polarity axis. When accurate positioning of the spindle fails, a surveillance mechanism named the Spindle Position Checkpoint (SPOC) prevents cells from exiting mitosis. Mutants with a defective SPOC become multinucleated and lose their genomic integrity. Yet, a comprehensive understanding of the SPOC mechanism is missing. In this study, we identified the type 1 protein phosphatase, Glc7, in association with its regulatory protein Bud14 as a novel checkpoint component. We further showed that Glc7-Bud14 promotes dephosphorylation of the SPOC effector protein Bfa1. Our results suggest a model in which two mechanisms act in parallel for a robust checkpoint response: first, the SPOC kinase Kin4 isolates Bfa1 away from the inhibitory kinase Cdc5 and second, Glc7-Bud14 dephosphorylates Bfa1 to fully activate the checkpoint effector.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting file; Source Data files have been provided for Figures 2A-2C, 3A and 3C, 4B and 4D, 6A-6D, 7G and Figure 2-Figure Supplement 1B-C, Figure 5-Figure Supplement 2A, Figure 6-Figure Supplement 1A-1D, Figure 6-Figure Supplement 2C-2D, Figure 7- Figure supplement 2B

Article and author information

Author details

  1. Dilara Kocakaplan

    Molecular Biology and Genetics, Koç University, Istanbul, Turkey
    Competing interests
    The authors declare that no competing interests exist.
  2. Hüseyin Karaburk

    Molecular Biology and Genetics, Koç University, Istanbul, Turkey
    Competing interests
    The authors declare that no competing interests exist.
  3. Cansu Dilege

    Molecular Biology and Genetics, Koç University, Istanbul, Turkey
    Competing interests
    The authors declare that no competing interests exist.
  4. Idil Kirdök

    Molecular Biology and Genetics, Koç University, Istanbul, Turkey
    Competing interests
    The authors declare that no competing interests exist.
  5. Şeyma Nur Bektaş

    Molecular Biology and Genetics, Koç University, Istanbul, Turkey
    Competing interests
    The authors declare that no competing interests exist.
  6. Ayse Koca Caydasi

    Molecular Biology and Genetics, Koç University, Istanbul, Turkey
    For correspondence
    aykoca@ku.edu.tr
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2570-1367

Funding

EMBO (IG - 3918)

  • Dilara Kocakaplan
  • Ayse Koca Caydasi

TUBITAK (117Z232)

  • Ayse Koca Caydasi

TUBITAK (118Z979)

  • Hüseyin Karaburk
  • Idil Kirdök

European Commission (H2020-MSCA-IF (796599))

  • Ayse Koca Caydasi

ICGEB (IG-No. CRP/TUR17-04_EC)

  • Ayse Koca Caydasi

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: August 5, 2021
  2. Accepted: October 8, 2021
  3. Accepted Manuscript published: October 11, 2021 (version 1)

Copyright

© 2021, Kocakaplan 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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