1. Biochemistry and Chemical Biology
  2. Cell Biology
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Astrin-SKAP complex reconstitution reveals its kinetochore interaction with microtubule-bound Ndc80

  1. David M Kern
  2. Julie K Monda
  3. Kuan-Chung Su
  4. Elizabeth M Wilson-Kubalek
  5. Iain M Cheeseman  Is a corresponding author
  1. Whitehead Institute, United States
  2. The Scripps Research Institute, United States
Research Article
  • Cited 19
  • Views 2,732
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Cite this article as: eLife 2017;6:e26866 doi: 10.7554/eLife.26866

Abstract

Chromosome segregation requires robust interactions between the macromolecular kinetochore structure and dynamic microtubule polymers. A key outstanding question is how kinetochore-microtubule attachments are modulated to ensure that bi-oriented attachments are selectively stabilized and maintained. The Astrin-SKAP complex localizes preferentially to properly bi-oriented sister kinetochores, representing the final outer kinetochore component recruited prior to anaphase onset. Here, we reconstitute the 4-subunit Astrin-SKAP complex, including a novel MYCBP subunit. Our work demonstrates that the Astrin-SKAP complex contains separable kinetochore localization and microtubule binding domains. In addition, through cross-linking analysis in human cells and biochemical reconstitution, we show that the Astrin-SKAP complex binds synergistically to microtubules with the Ndc80 complex to form an integrated interface. We propose a model in which the Astrin-SKAP complex acts together with the Ndc80 complex to stabilize correctly formed kinetochore-microtubule interactions.

Article and author information

Author details

  1. David M Kern

    Department of Biology, MIT, Whitehead Institute, Cambridge, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8529-9045
  2. Julie K Monda

    Department of Biology, MIT, Whitehead Institute, Cambridge, MA, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Kuan-Chung Su

    Department of Biology, MIT, Whitehead Institute, Cambridge, MA, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Elizabeth M Wilson-Kubalek

    Department of Cell Biology, The Scripps Research Institute, La Jolla, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Iain M Cheeseman

    Department of Biology, MIT, Whitehead Institute, Cambridge, MA, United States
    For correspondence
    icheese@wi.mit.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3829-5612

Funding

National Institute of General Medical Sciences (GM088313)

  • Iain M Cheeseman

Leukemia and Lymphoma Society (Scholar Award)

  • Iain M Cheeseman

National Institute of General Medical Sciences (GM052468)

  • Elizabeth M Wilson-Kubalek

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

Reviewing Editor

  1. Jon Pines, The Gurdon Institute, United Kingdom

Publication history

  1. Received: March 16, 2017
  2. Accepted: August 24, 2017
  3. Accepted Manuscript published: August 25, 2017 (version 1)
  4. Version of Record published: September 18, 2017 (version 2)
  5. Version of Record updated: September 21, 2017 (version 3)

Copyright

© 2017, Kern 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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