1. Structural Biology and Molecular Biophysics
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The structure of the yeast Ctf3 complex

  1. Stephen M Hinshaw  Is a corresponding author
  2. Andrew N Dates
  3. Stephen C Harrison  Is a corresponding author
  1. Howard Hughes Medical Institute, Harvard Medical School, United States
  2. Harvard University, United States
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  • Views 1,668
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Cite this article as: eLife 2019;8:e48215 doi: 10.7554/eLife.48215

Abstract

Kinetochores are the chromosomal attachment points for spindle microtubules. They are also signaling hubs that control major cell cycle transitions and coordinate chromosome folding. Most well-studied eukaryotes rely on a conserved set of factors, which are divided among two loosely-defined groups, for these functions. Outer kinetochore proteins contact microtubules or regulate this contact directly. Inner kinetochore proteins designate the kinetochore assembly site by recognizing a specialized nucleosome containing the H3 variant Cse4/CENP-A. We previously determined the structure, resolved by cryo-electron microscopy (cryo-EM), of the yeast Ctf19 complex (Ctf19c, homologous to the vertebrate CCAN), providing a high-resolution view of inner kinetochore architecture (Hinshaw and Harrison, 2019). We now extend these observations by reporting a near-atomic model of the Ctf3 complex, the outermost Ctf19c sub-assembly seen in our original cryo-EM density. The model is sufficiently well-determined by the new data to enable molecular interpretation of Ctf3 recruitment and function.

Data availability

The final Ctf3c cryo-EM map and the soft mask used for three-dimensional refinements of fully unbinned particles have been deposited with accession code EMD-20200. The refined Ctf3c model has been deposited with accession code 6OUA.

The following previously published data sets were used

Article and author information

Author details

  1. Stephen M Hinshaw

    Howard Hughes Medical Institute, Harvard Medical School, Boston, United States
    For correspondence
    hinshaw@crystal.harvard.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4215-5206
  2. Andrew N Dates

    Program in Chemical Biology, Harvard University, Cambridge, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Stephen C Harrison

    Howard Hughes Medical Institute, Harvard Medical School, Boston, United States
    For correspondence
    harrison@crystal.harvard.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7215-9393

Funding

Howard Hughes Medical Institute

  • Stephen M Hinshaw

Howard Hughes Medical Institute

  • Stephen C Harrison

Helen Hay Whitney Foundation

  • Stephen M Hinshaw

National Institutes of Health (5T32GM095450-08)

  • Andrew N Dates

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: May 9, 2019
  2. Accepted: June 12, 2019
  3. Accepted Manuscript published: June 13, 2019 (version 1)
  4. Version of Record published: July 1, 2019 (version 2)

Copyright

© 2019, Hinshaw 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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