Genetic defects in β-spectrin and tau sensitize C. elegans axons to movement-induced damage via torque-tension coupling

  1. Michael Krieg
  2. Jan Stühmer
  3. Juan G Cueva
  4. Richard Fetter
  5. Kerri A Spliker
  6. Daniel Cremers
  7. Kang Shen
  8. Alexander R Dunn
  9. Miriam B Goodman  Is a corresponding author
  1. Institute of Photonic Sciences, Spain
  2. Technical University of Munich, Germany
  3. Stanford University, United States

Abstract

Our bodies are in constant motion and so are the neurons that invade each tissue. Motion-induced neuron deformation and damage are associated with several neurodegenerative conditions. Here, we investigated the question of how the neuronal cytoskeleton protects axons and dendrites from mechanical stress, exploiting mutations in UNC-70 β-spectrin, PTL-1 tau/MAP2-like and MEC-7 β-tubulin proteins in Caenorhabditis elegans. We found that mechanical stress induces supercoils and plectonemes in the sensory axons of spectrin and tau double mutants. Biophysical measurements, super-resolution and electron microscopy, as well as numerical simulations of neurons as discrete, elastic rods provide evidence that a balance of torque, tension, and elasticity stabilizes neurons against mechanical deformation. We conclude that the spectrin and microtubule cytoskeletons work in combination to protect axons and dendrites from mechanical stress, and propose that defects in -spectrin and tau may sensitize neurons to damage.

Article and author information

Author details

  1. Michael Krieg

    Institute of Photonic Sciences, Barcelona, Spain
    Competing interests
    No competing interests declared.
  2. Jan Stühmer

    Department of Informatics, Technical University of Munich, München, Germany
    Competing interests
    No competing interests declared.
  3. Juan G Cueva

    Department of Molecular and Cellular Physiology, Stanford University, Stanford, United States
    Competing interests
    No competing interests declared.
  4. Richard Fetter

    Department of Molecular and Cellular Physiology, Stanford University, Stanford, United States
    Competing interests
    No competing interests declared.
  5. Kerri A Spliker

    Institute of Photonic Sciences, Barcelona, Spain
    Competing interests
    No competing interests declared.
  6. Daniel Cremers

    Department of Informatics, Technical University of Munich, München, Germany
    Competing interests
    No competing interests declared.
  7. Kang Shen

    Department of Biology, Stanford University, Stanford, United States
    Competing interests
    Kang Shen, Reviewing editor, eLife.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4059-8249
  8. Alexander R Dunn

    Department of Chemical Engineering, Stanford University, Stanford, United States
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-6096-4600
  9. Miriam B Goodman

    Department of Molecular and Cellular Physiology, Stanford University, Stanford, United States
    For correspondence
    mbgoodmn@stanford.edu
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5810-1272

Funding

National Institute of Neurological Disorders and Stroke (R01NS092099-02)

  • Alexander R Dunn
  • Miriam B Goodman

National Institute of Neurological Disorders and Stroke (5K99NS089942-02)

  • Michael Krieg

Howard Hughes Medical Institute

  • Kang Shen
  • Alexander R Dunn

H2020 European Research Council (ERC-2014-CoG)

  • Jan Stühmer
  • Daniel Cremers

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

Reviewing Editor

  1. Anna Akhmanova, Utrecht University, Netherlands

Publication history

  1. Received: July 29, 2016
  2. Accepted: January 17, 2017
  3. Accepted Manuscript published: January 18, 2017 (version 1)
  4. Version of Record published: February 8, 2017 (version 2)
  5. Version of Record updated: February 10, 2017 (version 3)

Copyright

© 2017, Krieg 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. Michael Krieg
  2. Jan Stühmer
  3. Juan G Cueva
  4. Richard Fetter
  5. Kerri A Spliker
  6. Daniel Cremers
  7. Kang Shen
  8. Alexander R Dunn
  9. Miriam B Goodman
(2017)
Genetic defects in β-spectrin and tau sensitize C. elegans axons to movement-induced damage via torque-tension coupling
eLife 6:e20172.
https://doi.org/10.7554/eLife.20172
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