1. Neuroscience
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Sonic Hedgehog switches on Wnt/planar cell polarity signaling in commissural axon growth cones by reducing levels of Shisa2

  1. Keisuke Onishi
  2. Yimin Zou  Is a corresponding author
  1. University of California, San Diego, United States
Research Article
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Cite this article as: eLife 2017;6:e25269 doi: 10.7554/eLife.25269


Commissural axons switch on responsiveness to Wnt attraction during midline crossing to turn anteriorly after exiting the floor plate. We report here Sonic Hedgehog (Shh) downregulates Shisa2, which inhibits glycosylation and cell surface presentation of Frizzled3 in rodent commissural axon growth cones. Constitutive Shisa2 expression causes randomized turning of post-crossing commissural axons along the anterior-posterior (A-P) axis. Loss of Shisa2 lead to precocious anterior turning of commissural axons before or during midline crossing. Post-crossing commissural axon turning is completely randomized along the A-P axis when Wntless, essential for Wnt secretion, is conditionally knocked out in the floor plate. The regulatory link between Shh and PCP signaling may also occur in other developmental processes.

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Author details

  1. Keisuke Onishi

    Neurobiology Section, Biological Sciences Division, University of California, San Diego, La Jalla, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Yimin Zou

    Neurobiology Section, Biological Sciences Division, University of California, San Diego, La Jolla, United States
    For correspondence
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-1092-5547


NINDS (NS047484)

  • Yimin Zou

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


Animal experimentation: Experiments were conducted in accordance with the NIH Guide for the Care and Use of LaboratoryAnimals and approved by the UCSD Animal Subjects Committee (Approved Protocol #: S06219, S06222).

Reviewing Editor

  1. Carol A Mason, Columbia University, United States

Publication history

  1. Received: January 19, 2017
  2. Accepted: August 17, 2017
  3. Accepted Manuscript published: September 8, 2017 (version 1)
  4. Version of Record published: September 18, 2017 (version 2)


© 2017, Onishi & Zou

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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