The Ndc80 complex bridges two Dam1 complex rings

  1. Jae ook Kim
  2. Alex Zelter
  3. Neil T Umbreit
  4. Athena Bollozos
  5. Michael Riffle
  6. Richard Johnson
  7. Michael J MacCoss
  8. Charles L Asbury
  9. Trisha N Davis  Is a corresponding author
  1. University of Washington, United States
  2. Dana-Farber Cancer Institute, United States

Abstract

Strong kinetochore-microtubule attachments are essential for faithful segregation of sister chromatids during mitosis. The Dam1 and Ndc80 complexes are the main microtubule binding components of the Saccharomyces cerevisiae kinetochore. Cooperation between these two complexes enhances kinetochore-microtubule coupling and is regulated by Aurora B kinase. We show that the Ndc80 complex can simultaneously bind and bridge across two Dam1 complex rings through a tripartite interaction, each component of which is regulated by Aurora B kinase. Mutations in any one of the Ndc80p interaction regions abrogates the Ndc80 complex's ability to bind two Dam1 rings in vitro, and results in kinetochore biorientation and microtubule attachment defects in vivo. We also show that an extra-long Ndc80 complex, engineered to space the two Dam1 rings further apart, does not support growth. Taken together, our work suggests that each kinetochore in vivo contains two Dam1 rings and that proper spacing between the rings is vital.

Article and author information

Author details

  1. Jae ook Kim

    Department of Biochemistry, University of Washington, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Alex Zelter

    Department of Biochemistry, University of Washington, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Neil T Umbreit

    Department of Pediatric Oncology, Dana-Farber Cancer Institute, Massachusetts, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Athena Bollozos

    Department of Biochemistry, University of Washington, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Michael Riffle

    Department of Biochemistry, University of Washington, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Richard Johnson

    Department of Genome Sciences, University of Washington, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
  7. Michael J MacCoss

    Department of Genome Sciences, University of Washington, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
  8. Charles L Asbury

    Department of Physiology and Biophysics, University of Washington, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
  9. Trisha N Davis

    Department of Biochemistry, University of Washington, Seattle, United States
    For correspondence
    tdavis@uw.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4797-3152

Funding

National Institutes of Health (R01 GM040506)

  • Trisha N Davis

National Institutes of Health (P41 GM103533)

  • Michael J MacCoss

National Institutes of Health (R01 GM079373)

  • Charles L Asbury

National Institutes of Health (S10 RR026406)

  • Charles L Asbury

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

Reviewing Editor

  1. Andrea Musacchio, Max Planck Institute of Molecular Physiology, Germany

Publication history

  1. Received: August 29, 2016
  2. Accepted: February 11, 2017
  3. Accepted Manuscript published: February 13, 2017 (version 1)
  4. Version of Record published: March 16, 2017 (version 2)

Copyright

© 2017, Kim 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. Jae ook Kim
  2. Alex Zelter
  3. Neil T Umbreit
  4. Athena Bollozos
  5. Michael Riffle
  6. Richard Johnson
  7. Michael J MacCoss
  8. Charles L Asbury
  9. Trisha N Davis
(2017)
The Ndc80 complex bridges two Dam1 complex rings
eLife 6:e21069.
https://doi.org/10.7554/eLife.21069
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