Structural basis of Stu2 recruitment to yeast kinetochores

  1. Jacob A Zahm
  2. Michael G Stewart
  3. Joseph S Carrier
  4. Stephen C Harrison  Is a corresponding author
  5. Matthew P Miller  Is a corresponding author
  1. Howard Hughes Medical Institute, Harvard Medical School, United States
  2. University of Utah School of Medicine, United States

Abstract

Chromosome segregation during cell division requires engagement of kinetochores of sister chromatids with microtubules emanating from opposite poles. As the corresponding microtubules shorten, these 'bioriented' sister kinetochores experience tension-dependent stabilization of microtubule attachments. The yeast XMAP215 family member and microtubule polymerase, Stu2, associates with kinetochores and contributes to tension-dependent stabilization in vitro. We show here that a C-terminal segment of Stu2 binds the four-way junction of the Ndc80 complex (Ndc80c) and that residues conserved both in yeast Stu2 orthologs and in their metazoan counterparts make specific contacts with Ndc80 and Spc24. Mutations that perturb this interaction prevent association of Stu2 with kinetochores, impair cell viability, produce biorientation defects, and delay cell cycle progression. Ectopic tethering of the mutant Stu2 species to the Ndc80c junction restores wild-type function in vivo. These findings show that the role of Stu2 in tension-sensing depends on its association with kinetochores by binding with Ndc80c.

Data availability

Diffraction data have been deposited in PDB under the accession code: 7KDF

The following data sets were generated

Article and author information

Author details

  1. Jacob A Zahm

    1Department of Biological Chemistry and Molecular Pharmacology, Howard Hughes Medical Institute, Harvard Medical School, Boston, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Michael G Stewart

    Biochemistry, University of Utah School of Medicine, Salt Lake City, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Joseph S Carrier

    Biochemistry, University of Utah School of Medicine, Salt Lake City, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Stephen C Harrison

    1Department of Biological Chemistry and Molecular Pharmacology, 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
  5. Matthew P Miller

    Biochemistry, University of Utah School of Medicine, Salt Lake City, United States
    For correspondence
    matthew.miller@biochem.utah.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2012-7546

Funding

Damon Runyon Cancer Research Foundation (Dale F. Frey Award for Breakthrough Scientists,29-18)

  • Matthew P Miller

Howard Hughes Medical Institute

  • Stephen C Harrison

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

Reviewing Editor

  1. Jennifer G. DeLuca, Colorado State University, United States

Publication history

  1. Received: December 2, 2020
  2. Accepted: February 15, 2021
  3. Accepted Manuscript published: February 16, 2021 (version 1)
  4. Version of Record published: February 26, 2021 (version 2)

Copyright

© 2021, Zahm 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. Jacob A Zahm
  2. Michael G Stewart
  3. Joseph S Carrier
  4. Stephen C Harrison
  5. Matthew P Miller
(2021)
Structural basis of Stu2 recruitment to yeast kinetochores
eLife 10:e65389.
https://doi.org/10.7554/eLife.65389
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