Optogenetic control of PRC1 reveals its role in chromosome alignment on the spindle by overlap length-dependent forces

Abstract

During metaphase, chromosome position at the spindle equator is regulated by the forces exerted by kinetochore microtubules and polar ejection forces. However, the role of forces arising from mechanical coupling of sister kinetochore fibers with bridging fibers in chromosome alignment is unknown. Here we develop an optogenetic approach for acute removal of PRC1 to partially disassemble bridging fibers and show that they promote chromosome alignment. Tracking of the plus-end protein EB3 revealed longer antiparallel overlaps of bridging microtubules upon PRC1 removal, which was accompanied by misaligned and lagging kinetochores. Kif4A/kinesin-4 and Kif18A/kinesin-8 were found within the bridging fiber and largely lost upon PRC1 removal, suggesting that these proteins regulate the overlap length of bridging microtubules. We propose that PRC1-mediated crosslinking of bridging microtubules and recruitment of kinesins to the bridging fiber promotes chromosome alignment by overlap length-dependent forces transmitted to the associated kinetochore fibers.

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

Article and author information

Author details

  1. Mihaela Jagrić

    Division of Molecular Biology, Ruđer Bošković Institute, Zagreb, Croatia
    Competing interests
    The authors declare that no competing interests exist.
  2. Patrik Risteski

    Division of Molecular Biology, Ruđer Bošković Institute, Zagreb, Croatia
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2137-7491
  3. Jelena Martinčić

    Division of Molecular Biology, Ruđer Bošković Institute, Zagreb, Croatia
    Competing interests
    The authors declare that no competing interests exist.
  4. Ana Milas

    Division of Molecular Biology, Ruđer Bošković Institute, Zagreb, Croatia
    Competing interests
    The authors declare that no competing interests exist.
  5. Iva M Tolić

    Division of Molecular Biology, Ruđer Bošković Institute, Zagreb, Croatia
    For correspondence
    tolic@irb.hr
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1305-7922

Funding

European Research Council (ERC,GA number 647077)

  • Iva M Tolić

Croatian Science Foundation (HRZZ project IP-2014-09-4753)

  • Iva M Tolić

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

Reviewing Editor

  1. Julie P I Welburn, University of Edinburgh, United Kingdom

Version history

  1. Received: July 16, 2020
  2. Accepted: January 21, 2021
  3. Accepted Manuscript published: January 22, 2021 (version 1)
  4. Version of Record published: March 2, 2021 (version 2)

Copyright

© 2021, Jagrić 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. Mihaela Jagrić
  2. Patrik Risteski
  3. Jelena Martinčić
  4. Ana Milas
  5. Iva M Tolić
(2021)
Optogenetic control of PRC1 reveals its role in chromosome alignment on the spindle by overlap length-dependent forces
eLife 10:e61170.
https://doi.org/10.7554/eLife.61170

Share this article

https://doi.org/10.7554/eLife.61170

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