1. Biochemistry and Chemical Biology
  2. Structural Biology and Molecular Biophysics
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Tight bending of the Ndc80 complex provides intrinsic regulation of its binding to microtubules

  1. Emily Anne Scarborough
  2. Trisha N Davis  Is a corresponding author
  3. Charles L Asbury  Is a corresponding author
  1. University of Washington, United States
Research Article
  • Cited 6
  • Views 1,366
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Cite this article as: eLife 2019;8:e44489 doi: 10.7554/eLife.44489

Abstract

Regulation of the outer kinetochore complex Ndc80 is essential to ensure correct kinetochore-microtubule attachments during mitosis. Here we present a novel mechanism of regulation that is intrinsic to its structure; tight bending of the Ndc80 complex inhibits its microtubule binding. Using single molecule Förster resonance energy transfer (FRET), we show that the S. cerevisiae Ndc80 complex can fluctuate between straight and bent forms, and that binding of the complex to microtubules selects for straightened forms. The loop region of the complex enables its bent conformation, as deletion of the loop promotes straightening. In addition, the kinetochore complex MIND enhances microtubule binding by opposing the tightly bent, auto-inhibited conformation of the Ndc80 complex. We suggest that prior to its assembly at the kinetochore, the Ndc80 complex interchanges between bent (auto-inhibited) and open conformations. Once assembled, its association with MIND stabilizes the Ndc80 complex in a straightened form for higher affinity microtubule binding.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for Figures 1, 2, 3, 4 and 5, as well as Figure 1-figure supplement 1, Figure 3-figure supplement 1, Figure 4-figure supplement 1 and Figure 5-figure supplement 1.

Article and author information

Author details

  1. Emily Anne Scarborough

    Department of Biochemistry, University of Washington, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. 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
  3. Charles L Asbury

    Department of Physiology and Biophysics, University of Washington, Seattle, United States
    For correspondence
    casbury@uw.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0143-5394

Funding

National Institute of General Medical Sciences (T32 GM007270)

  • Emily Anne Scarborough

National Institute of General Medical Sciences (R01 GM040506)

  • Trisha N Davis

National Institute of General Medical Sciences (R01 GM079373)

  • Charles L Asbury

National Institute of General Medical Sciences (P01 GM105537)

  • 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. Iain M Cheeseman, Whitehead Institute, United States

Publication history

  1. Received: December 18, 2018
  2. Accepted: April 26, 2019
  3. Accepted Manuscript published: May 2, 2019 (version 1)
  4. Version of Record published: May 14, 2019 (version 2)

Copyright

© 2019, Scarborough 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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