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Filopodial dynamics and growth cone stabilization in Drosophila visual circuit development

  1. Mehmet Neset Özel
  2. Marion Langen
  3. Bassem A Hassan
  4. P Robin Hiesinger  Is a corresponding author
  1. University of Texas Southwestern Medical Center, United States
  2. University of California, San Francisco, United States
  3. Vlaams Instituut voor Biotechnologie, Belgium
Research Article
  • Cited 31
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Cite this article as: eLife 2015;4:e10721 doi: 10.7554/eLife.10721

Abstract

Filopodial dynamics are thought to control growth cone guidance, but the types and roles of growth cone dynamics underlying neural circuit assembly in a living brain are largely unknown. To address this issue, we have developed long-term, continuous, fast and high-resolution imaging of growth cone dynamics from axon growth to synapse formation in cultured Drosophila brains. Using R7 photoreceptor neurons as a model we show that >90% of the growth cone filopodia exhibit fast, stochastic dynamics that persist despite ongoing stepwise layer formation. Correspondingly, R7 growth cones stabilize early and change their final position by passive dislocation. N-Cadherin controls both fast filopodial dynamics and growth cone stabilization. Surprisingly, loss of N-Cadherin causes no primary targeting defects, but destabilizes R7 growth cones to jump between correct and incorrect layers. Hence, growth cone dynamics can influence wiring specificity without a direct role in target recognition and implement simple rules during circuit assembly.

Article and author information

Author details

  1. Mehmet Neset Özel

    Department of Physiology, University of Texas Southwestern Medical Center, Dallas, United States
    Competing interests
    The authors declare that no competing interests exist.

  2. Marion Langen

    Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, United States
    Competing interests
    The authors declare that no competing interests exist.

  3. Bassem A Hassan

    Center for the Biology of Disease, Vlaams Instituut voor Biotechnologie, Leuven, Belgium
    Competing interests
    The authors declare that no competing interests exist.

  4. P Robin Hiesinger

    Department of Physiology, University of Texas Southwestern Medical Center, Dallas, United States
    For correspondence
    robin.hiesinger@fu-berlin.de
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Christine E Holt, University of Cambridge, United Kingdom

Publication history

  1. Received: August 7, 2015
  2. Accepted: October 26, 2015
  3. Accepted Manuscript published: October 29, 2015 (version 1)
  4. Version of Record published: January 5, 2016 (version 2)

Copyright

© 2015, Özel 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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