1. Developmental Biology
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Notch signalling maintains Hedgehog responsiveness via a Gli-dependent mechanism during spinal cord patterning in zebrafish

  1. Craig T Jacobs
  2. Peng Huang  Is a corresponding author
  1. University of Calgary, Canada
Research Article
  • Cited 3
  • Views 1,616
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Cite this article as: eLife 2019;8:e49252 doi: 10.7554/eLife.49252

Abstract

Spinal cord patterning is orchestrated by multiple cell signalling pathways. Neural progenitors are maintained by Notch signalling, whereas ventral neural fates are specified by Hedgehog (Hh) signalling. However, how dynamic interactions between Notch and Hh signalling drive the precise pattern formation is still unknown. We applied the PHRESH (PHotoconvertible REporter of Signalling History) technique to analyse cell signalling dynamics in vivo during zebrafish spinal cord development. This approach reveals that Notch and Hh signalling display similar spatiotemporal kinetics throughout spinal cord patterning. Notch signalling functions upstream to control Hh response of neural progenitor cells. Using gain- and loss-of-function tools, we demonstrate that this regulation occurs not at the level of upstream regulators or primary cilia, but rather at the level of Gli transcription factors. Our results indicate that Notch signalling maintains Hh responsiveness of neural progenitors via a Gli-dependent mechanism in the spinal cord.

Article and author information

Author details

  1. Craig T Jacobs

    Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, Canada
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0459-2838
  2. Peng Huang

    Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, Canada
    For correspondence
    huangp@ucalgary.ca
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7954-8869

Funding

Natural Sciences and Engineering Research Council of Canada (RGPIN-2015-06343)

  • Peng Huang

Canada Foundation for Innovation (Project 32920)

  • Peng Huang

Alberta Children's Hospital Research Institute (Startup fund)

  • Peng Huang

Alberta Children's Hospital Research Institute (Graduate Scholarship)

  • Craig T Jacobs

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

Ethics

Animal experimentation: All procedures was conducted in accordance with the principles outlined in the current Guidelines of the Canadian Council on Animal Care. All protocols were approved by the Animal Care Committee at the University of Calgary (#AC17-0128).

Reviewing Editor

  1. Tanya T Whitfield, University of Sheffield, United Kingdom

Publication history

  1. Received: June 11, 2019
  2. Accepted: August 19, 2019
  3. Accepted Manuscript published: August 27, 2019 (version 1)
  4. Version of Record published: September 9, 2019 (version 2)

Copyright

© 2019, Jacobs & Huang

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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