Microneedle manipulation of the mammalian spindle reveals specialized, short-lived reinforcement near chromosomes

  1. Pooja Suresh
  2. Alexandra F Long
  3. Sophie Dumont  Is a corresponding author
  1. University of California, San Francisco, United States

Abstract

The spindle generates force to segregate chromosomes at cell division. In mammalian cells, kinetochore-fibers connect chromosomes to the spindle. The dynamic spindle anchors kinetochore-fibers in space and time to move chromosomes. Yet, how it does so remains poorly understood as we lack tools to directly challenge this anchorage. Here, we adapt microneedle manipulation to exert local forces on the spindle with spatiotemporal control. Pulling on kinetochore-fibers reveals the preservation of local architecture in the spindle-center over seconds. Sister, but not neighbor, kinetochore-fibers remain tightly coupled, restricting chromosome stretching. Further, pulled kinetochore-fibers pivot around poles but not chromosomes, retaining their orientation within 3 μm of chromosomes. This local reinforcement has a 20 s lifetime, and requires the microtubule crosslinker PRC1. Together, these observations indicate short-lived, specialized reinforcement in the spindle center. This could help protect chromosome attachments from transient forces while allowing spindle remodeling, and chromosome movements, over longer timescales.

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Source data for all main and supplementary figures have been provided

Article and author information

Author details

  1. Pooja Suresh

    Biophysics Graduate Program, University of California, San Francisco, San Francisco, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Alexandra F Long

    Department of Cell and Tissue Biology, University of California, San Francisco, San Francisco, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. 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

National Institute of General Medical Sciences (DP2GM119177)

  • Sophie Dumont

National Institute of General Medical Sciences (1R01GM134132)

  • Sophie Dumont

National Science Foundation (1554139 CAREER)

  • Sophie Dumont

National Science Foundation (1548297 Center for Cellular Construction)

  • Sophie Dumont

Rita Allen Foundation

  • Sophie Dumont

Chicago Community Trust (Searle Scholars' Program)

  • Sophie Dumont

National Science Foundation (Graduate Research Fellowship)

  • Pooja Suresh
  • Alexandra F Long

University of California, San Francisco (UCSF Kozloff Fellowship)

  • Alexandra F Long

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), Spain

Publication history

  1. Received: November 21, 2019
  2. Accepted: March 18, 2020
  3. Accepted Manuscript published: March 19, 2020 (version 1)
  4. Version of Record published: April 2, 2020 (version 2)

Copyright

© 2020, Suresh 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. Pooja Suresh
  2. Alexandra F Long
  3. Sophie Dumont
(2020)
Microneedle manipulation of the mammalian spindle reveals specialized, short-lived reinforcement near chromosomes
eLife 9:e53807.
https://doi.org/10.7554/eLife.53807

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