The mitotic spindle protein CKAP2 potently increases formation and stability of microtubules

  1. Thomas S McAlear
  2. Susanne Bechstedt  Is a corresponding author
  1. McGill University, Canada

Abstract

Cells increase microtubule dynamics to make large rearrangements to their microtubule cytoskeleton during cell division. Changes in microtubule dynamics are essential for the formation and function of the mitotic spindle, and misregulation can lead to aneuploidy and cancer. Using in vitro reconstitution assays we show that the mitotic spindle protein Cytoskeleton-Associated Protein 2 (CKAP2) has a strong effect on nucleation of microtubules by lowering the critical tubulin concentration 100-fold. CKAP2 increases the apparent rate constant ka of microtubule growth by 50-fold and increases microtubule growth rates. In addition, CKAP2 strongly suppresses catastrophes. Our results identify CKAP2 as the most potent microtubule growth factor to date. These finding help explain CKAP2's role as an important spindle protein, proliferation marker, and oncogene.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting files.

Article and author information

Author details

  1. Thomas S McAlear

    Department of Anatomy and Cell Biology, McGill University, Montréal, Canada
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-6097-0103
  2. Susanne Bechstedt

    Department of Anatomy and Cell Biology, McGill University, Montréal, Canada
    For correspondence
    susanne.bechstedt@mcgill.ca
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4706-9975

Funding

Canadian Institutes of Health Research (CIHR PJT-156193)

  • Susanne Bechstedt

Natural Sciences and Engineering Research Council of Canada (RGPIN-2017-04649)

  • Susanne Bechstedt

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: July 14, 2021
  2. Preprint posted: July 20, 2021 (view preprint)
  3. Accepted: January 13, 2022
  4. Accepted Manuscript published: January 14, 2022 (version 1)
  5. Version of Record published: January 28, 2022 (version 2)

Copyright

© 2022, McAlear & Bechstedt

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. Thomas S McAlear
  2. Susanne Bechstedt
(2022)
The mitotic spindle protein CKAP2 potently increases formation and stability of microtubules
eLife 11:e72202.
https://doi.org/10.7554/eLife.72202

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