The human Ska complex drives the metaphase-anaphase cell cycle transition by recruiting protein phosphatase 1 to kinetochores

  1. Sushama Sivakumar
  2. Paweł Ł Janczyk
  3. Qianhui Qu
  4. Chad A Brautigam
  5. P Todd Stukenberg
  6. Hongtao Yu
  7. Gary J Gorbsky  Is a corresponding author
  1. Oklahoma Medical Research Foundation, United States
  2. University of Virginia School of Medicine, United States
  3. Howard Hughes Medical Institute, University of Texas Southwestern Medical center, United States
  4. University of Texas Southwestern Medical center, United States

Abstract

The spindle- and kinetochore-associated (Ska) complex is essential for normal anaphase onset in mitosis. The C-terminal domain (CTD) of Ska1 binds microtubules and was proposed to facilitate kinetochore movement on depolymerizing spindle microtubules. Here we show that Ska complex recruits protein phosphatase 1 (PP1) to kinetochores. This recruitment requires the Ska1 CTD, which binds PP1 in vitro and in human HeLa cells. Ska1 lacking its CTD fused to a PP1-binding peptide or fused directly to PP1 rescues mitotic defects caused by Ska1 depletion. Ska1 fusion to catalytically dead PP1 mutant does not rescue and shows dominant negative effects. Thus, the Ska complex, specifically the Ska1 CTD, recruits PP1 to kinetochores to oppose spindle checkpoint signaling kinases and promote anaphase onset. Microtubule binding by Ska, rather than acting in force production for chromosome movement, may instead serve to promote PP1 recruitment to kinetochores fully attached to spindle microtubules at metaphase.

Article and author information

Author details

  1. Sushama Sivakumar

    Cell Cycle and Cancer Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Paweł Ł Janczyk

    Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Qianhui Qu

    Department of Pharmacology, Howard Hughes Medical Institute, University of Texas Southwestern Medical center, Dallas, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Chad A Brautigam

    Department of Biophysics, University of Texas Southwestern Medical center, Dallas, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. P Todd Stukenberg

    Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Hongtao Yu

    Department of Pharmacology, Howard Hughes Medical Institute, University of Texas Southwestern Medical center, Dallas, United States
    Competing interests
    The authors declare that no competing interests exist.
  7. Gary J Gorbsky

    Cell Cycle and Cancer Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, United States
    For correspondence
    GJG@omrf.org
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Sue Biggins, Fred Hutchinson Cancer Research Center, United States

Version history

  1. Received: November 7, 2015
  2. Accepted: March 3, 2016
  3. Accepted Manuscript published: March 16, 2016 (version 1)
  4. Accepted Manuscript updated: March 21, 2016 (version 2)
  5. Version of Record published: March 29, 2016 (version 3)

Copyright

© 2016, Sivakumar 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. Sushama Sivakumar
  2. Paweł Ł Janczyk
  3. Qianhui Qu
  4. Chad A Brautigam
  5. P Todd Stukenberg
  6. Hongtao Yu
  7. Gary J Gorbsky
(2016)
The human Ska complex drives the metaphase-anaphase cell cycle transition by recruiting protein phosphatase 1 to kinetochores
eLife 5:e12902.
https://doi.org/10.7554/eLife.12902

Share this article

https://doi.org/10.7554/eLife.12902

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