1. Developmental Biology
  2. Neuroscience
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Frazzled promotes growth cone attachment at the source of a Netrin gradient in the Drosophila visual system

  1. Orkun Akin  Is a corresponding author
  2. S Lawrence Zipursky  Is a corresponding author
  1. Howard Hughes Medical Institute, University of California, Los Angeles, United States
Research Article
  • Cited 41
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Cite this article as: eLife 2016;5:e20762 doi: 10.7554/eLife.20762

Abstract

Axon guidance is proposed to act through a combination of long- and short-range attractive and repulsive cues. The ligand-receptor pair, Netrin (Net) and Frazzled (Fra) (DCC, Deleted in Colorectal Cancer, in vertebrates), is recognized as the prototypical effector of chemoattraction, with roles in both long- and short-range guidance. In the Drosophila visual system, R8 photoreceptor growth cones were shown to require Net-Fra to reach their target, the peak of a Net gradient. Using live imaging, we show, however, that R8 growth cones reach and recognize their target without Net, Fra, or Trim9, a conserved binding partner of Fra, but do not remain attached to it. Thus, despite the graded ligand distribution along the guidance path, Net-Fra is not used for chemoattraction. Based on findings in other systems, we propose that adhesion to substrate-bound Net underlies both long- and short-range Net-Fra-dependent guidance in vivo, thereby eroding the distinction between them.

Article and author information

Author details

  1. Orkun Akin

    Department of Biological Chemistry, Howard Hughes Medical Institute, University of California, Los Angeles, Los Angeles, United States
    For correspondence
    akin.orkun@gmail.com
    Competing interests
    The authors declare that no competing interests exist.
  2. S Lawrence Zipursky

    Department of Biological Chemistry, Howard Hughes Medical Institute, University of California, Los Angeles, Los Angeles, United States
    For correspondence
    lzipursky@mednet.ucla.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5630-7181

Funding

Howard Hughes Medical Institute

  • S Lawrence Zipursky

Damon Runyon Cancer Research Foundation

  • Orkun Akin

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

Reviewing Editor

  1. Graeme W Davis, University of California, San Francisco, United States

Publication history

  1. Received: August 18, 2016
  2. Accepted: October 14, 2016
  3. Accepted Manuscript published: October 15, 2016 (version 1)
  4. Version of Record published: November 14, 2016 (version 2)

Copyright

© 2016, Akin & Zipursky

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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