Abstract

Axon navigation depends on the interactions between guidance molecules along the trajectory and specific receptors on the growth cone. However, our in vitro and in vivo studies on the role of Endoglycan demonstrate that in addition to specific guidance cue – receptor interactions, axon guidance depends on fine-tuning of cell-cell adhesion. Endoglycan, a sialomucin, plays a role in axon guidance in the central nervous system of chicken embryos, but it is neither an axon guidance cue nor a receptor. Rather Endoglycan acts as a negative regulator of molecular interactions based on evidence from in vitro experiments demonstrating reduced adhesion of growth cones . In the absence of Endoglycan, commissural axons fail to properly navigate the midline of the spinal cord. Taken together, our in vivo and in vitro results support the hypothesis that Endoglycan acts as a negative regulator of cell-cell adhesion, in commissural axon guidance.

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

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Author details

  1. Thomas Baeriswyl

    Molecular Life Sciences, University of Zurich, Zurich, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  2. Alexandre Dumoulin

    Molecular Life Sciences, University of Zurich, Zurich, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2420-6877
  3. Martina Schaettin

    Molecular Life Sciences and Neuroscience Center Zurich, University of Zurich, Zurich, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  4. Georgia Tsapara

    Molecular Life Sciences and Neuroscience Center Zurich, University of Zurich, Zurich, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  5. Vera Niederkofler

    Molecular Life Sciences, University of Zurich, Zurich, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  6. Denise Helbling

    Molecular Life Sciences and Neuroscience Center Zurich, University of Zurich, Zurich, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  7. Evelyn Avilés

    Molecular Life Sciences and Neuroscience Center Zurich, University of Zurich, Zurich, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  8. Jeannine A Frei

    Molecular Life Sciences and Neuroscience Center Zurich, University of Zurich, Zurich, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  9. Nicole H Wilson

    Molecular Life Sciences, University of Zurich, Zurich, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  10. Matthias Gesemann

    Molecular Life Sciences and Neuroscience Center Zurich, University of Zurich, Zurich, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  11. Beat Kunz

    Molecular Life Sciences and Neuroscience Center Zurich, University of Zurich, Zurich, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  12. Esther T Stoeckli

    Molecular Life Sciences and Neuroscience Center Zurich, University of Zurich, Zurich, Switzerland
    For correspondence
    esther.stoeckli@mls.uzh.ch
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-8485-0648

Funding

Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung

  • Esther T Stoeckli

Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung (Brain Plasticy and Repair)

  • Esther T Stoeckli

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

Reviewing Editor

  1. Carol A Mason, Columbia University, United States

Version history

  1. Received: November 10, 2020
  2. Accepted: February 25, 2021
  3. Accepted Manuscript published: March 2, 2021 (version 1)
  4. Version of Record published: March 10, 2021 (version 2)

Copyright

© 2021, Baeriswyl 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. Thomas Baeriswyl
  2. Alexandre Dumoulin
  3. Martina Schaettin
  4. Georgia Tsapara
  5. Vera Niederkofler
  6. Denise Helbling
  7. Evelyn Avilés
  8. Jeannine A Frei
  9. Nicole H Wilson
  10. Matthias Gesemann
  11. Beat Kunz
  12. Esther T Stoeckli
(2021)
Endoglycan plays a role in axon guidance by modulating cell adhesion
eLife 10:e64767.
https://doi.org/10.7554/eLife.64767

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