1. Cell Biology
  2. Physics of Living Systems

Kinetochore-fiber lengths are maintained locally but coordinated globally by polesin the mammalian spindle

  1. Manuela Richter  Is a corresponding author
  2. Lila Neahring
  3. Jinghui Tao
  4. Renaldo Sutanto
  5. Nathan H Cho
  6. Sophie Dumont  Is a corresponding author
  1. University of California - San Francisco, United States
https://doi.org/10.7554/eLife.85208
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  1. Manuela Richter
  2. Lila Neahring
  3. Jinghui Tao
  4. Renaldo Sutanto
  5. Nathan H Cho
  6. Sophie Dumont
(2023)
Kinetochore-fiber lengths are maintained locally but coordinated globally by polesin the mammalian spindle
eLife 12:e85208.
https://doi.org/10.7554/eLife.85208
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Abstract

At each cell division, nanometer-scale components self-organize to build a micron-scale spindle. In mammalian spindles, microtubule bundles called kinetochore-fibers attach to chromosomes and focus into spindle poles. Despite evidence suggesting that poles can set spindle length, their role remains poorly understood. In fact, many species do not have spindle poles. Here, we probe the pole's contribution to mammalian spindle length, dynamics, and function by inhibiting dynein to generate spindles whose kinetochore-fibers do not focus into poles, yet maintain a metaphase steady-state length. We find that unfocused kinetochore-fibers have a mean length indistinguishable from control, but a broader length distribution, and reduced length coordination between sisters and neighbors. Further, we show that unfocused kinetochore-fibers, like control, can grow back to their steady-state length if acutely shortened by drug treatment or laser ablation: they recover their length by tuning their end dynamics, albeit slower due to their reduced baseline dynamics. Thus, kinetochore-fiber dynamics are regulated by their length, not just pole-focusing forces. Finally, we show that spindles with unfocused kinetochore-fibers can segregate chromosomes but fail to correctly do so. We propose that mammalian spindle length emerges locally from individual k-fibers while spindle poles globally coordinate k-fibers across space and time.

Data availability

We provide all source data and analyzed data for all figures. We provide source code for Figure 1.

Article and author information

Author details

  1. Manuela Richter

    Tetrad Graduate Program, University of California - San Francisco, San Francisco, United States
    For correspondence
    manuela.richter@ucsf.edu
    Competing interests
    The authors declare that no competing interests exist.

  2. Lila Neahring

    Department of Bioengineering and Therapeutic Sciences, University of California - San Francisco, San Francisco, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2272-8732

  3. Jinghui Tao

    Department of Bioengineering and Therapeutic Sciences, University of California - San Francisco, San Francisco, United States
    Competing interests
    The authors declare that no competing interests exist.

  4. Renaldo Sutanto

    Department of Bioengineering and Therapeutic Sciences, University of California - San Francisco, San Francisco, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-1252-1482

  5. Nathan H Cho

    Tetrad Graduate Program, University of California - San Francisco, San Francisco, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0110-1343

  6. Sophie Dumont

    Department of Cell and Tissue Biology, University of California - San Francisco, San Francisco, United States
    For correspondence
    sophie.dumont@ucsf.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-8283-1523

Funding

Achievement Rewards for College Scientists Foundation (Graduate Student Scholarship)

  • Manuela Richter

Hertz Foundation (Hertz Fellowship)

  • Lila Neahring

American Heart Association (Predoctoral Fellowship)

  • Nathan H Cho

University of California, San Francisco (Discovery Fellows Program)

  • Lila Neahring
  • Nathan H Cho

National Science Foundation (Graduate Research Fellowship Program)

  • Manuela Richter

University of California, San Francisco (PIBS Bishop Fellowship)

  • Manuela Richter

National Institutes of Health (NIHR35GM136420)

  • Sophie Dumont

National Science Foundation (NSF CAREER 1554139)

  • Sophie Dumont

National Science Foundation (NSF 1548297 Center for Cellular Construction)

  • Sophie Dumont

Chan Zuckerberg Initiative (Chan Zuckerberg Biohub)

  • Sophie Dumont

University of California, San Francisco (Byers Award)

  • Sophie Dumont

University of California, San Francisco (Program for Breakthrough Biomedical Research (PBBR))

  • Sophie Dumont

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

Reviewing Editor

  1. Thomas Surrey, Centre for Genomic Regulation (CRG), Barcelona, Spain, Spain

Version history

  1. Preprint posted: November 26, 2022 (view preprint)
  2. Received: November 28, 2022
  3. Accepted: July 2, 2023
  4. Accepted Manuscript published: July 3, 2023 (version 1)
  5. Accepted Manuscript updated: July 7, 2023 (version 2)
  6. Version of Record published: July 14, 2023 (version 3)

Copyright

© 2023, Richter 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. Manuela Richter
  2. Lila Neahring
  3. Jinghui Tao
  4. Renaldo Sutanto
  5. Nathan H Cho
  6. Sophie Dumont
(2023)
Kinetochore-fiber lengths are maintained locally but coordinated globally by polesin the mammalian spindle
eLife 12:e85208.
https://doi.org/10.7554/eLife.85208

Share this article

https://doi.org/10.7554/eLife.85208

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