Neck linker docking is critical for Kinesin-1 force generation in cells but at a cost to motor speed and processivity

  1. Breane G Budaitis
  2. Shashank Jariwala
  3. Dana N Reinemann
  4. Kristin I Schimert
  5. Guido Scarabelli
  6. Barry J Grant
  7. David Sept
  8. Matthew J Lang
  9. Kristen J Verhey  Is a corresponding author
  1. University of Michigan, United States
  2. Vanderbilt University, United States
  3. University of California, San Diego, United States

Abstract

Kinesin force generation involves ATP-induced docking of the neck linker (NL) along the motor core. However, the roles of the proposed steps of NL docking, cover-neck bundle (CNB) and asparagine latch (N-latch) formation, during force generation are unclear. Furthermore, the necessity of NL docking for transport of membrane-bound cargo in cells has not been tested. We generated kinesin-1 motors impaired in CNB and/or N-latch formation based on molecular dynamics simulations. The mutant motors displayed reduced force output and inability to stall in optical trap assays but exhibited increased speeds, run lengths, and landing rates under unloaded conditions. NL docking thus enhances force production but at a cost to speed and processivity. In cells, teams of mutant motors were hindered in their ability to drive transport of Golgi elements (high-load cargo) but not peroxisomes (low-load cargo). These results demonstrate that the NL serves as a mechanical element for kinesin-1 transport under physiological conditions.

Data availability

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

Article and author information

Author details

  1. Breane G Budaitis

    Cellular and Molecular Biology Program, University of Michigan, Ann Arbor, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Shashank Jariwala

    Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Dana N Reinemann

    Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Kristin I Schimert

    Biophysics Program, University of Michigan, Ann Arbor, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9209-7986
  5. Guido Scarabelli

    Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Barry J Grant

    Division of Biological Sciences, Section of Molecular Biology, University of California, San Diego, La Jolla, United States
    Competing interests
    The authors declare that no competing interests exist.
  7. David Sept

    Department of Biomedical Engineering, University of Michigan, Ann Arbor, United States
    Competing interests
    The authors declare that no competing interests exist.
  8. Matthew J Lang

    Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, United States
    Competing interests
    The authors declare that no competing interests exist.
  9. Kristen J Verhey

    Cell and Developmental Biology Program, University of Michigan, Ann Arbor, United States
    For correspondence
    kjverhey@umich.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9329-4981

Funding

National Institutes of Health (R01GM070862)

  • Barry J Grant

National Science Foundation (1330792)

  • Matthew J Lang

Qatar Leadership Program (R35 GM130293)

  • Shashank Jariwala

National Science Foundation (1256260)

  • Breane G Budaitis

National Science Foundation (1445197)

  • Dana N Reinemann

National Institutes of Health (T32GM007315)

  • Breane G Budaitis

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, The Francis Crick Institute, United Kingdom

Publication history

  1. Received: December 5, 2018
  2. Accepted: May 9, 2019
  3. Accepted Manuscript published: May 14, 2019 (version 1)
  4. Version of Record published: May 23, 2019 (version 2)

Copyright

© 2019, Budaitis 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. Breane G Budaitis
  2. Shashank Jariwala
  3. Dana N Reinemann
  4. Kristin I Schimert
  5. Guido Scarabelli
  6. Barry J Grant
  7. David Sept
  8. Matthew J Lang
  9. Kristen J Verhey
(2019)
Neck linker docking is critical for Kinesin-1 force generation in cells but at a cost to motor speed and processivity
eLife 8:e44146.
https://doi.org/10.7554/eLife.44146

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