1. Developmental Biology
  2. Neuroscience
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Pioneer neurog1 expressing cells ingress into the otic epithelium and instruct neuronal specification

  1. Esteban Hoijman  Is a corresponding author
  2. Laura Fargas
  3. Patrick Blader
  4. Berta Alsina  Is a corresponding author
  1. Universitat Pompeu Fabra, Spain
  2. Université de Toulouse, France
Research Article
  • Cited 3
  • Views 1,694
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Cite this article as: eLife 2017;6:e25543 doi: 10.7554/eLife.25543

Abstract

Neural patterning involves regionalised cell specification. Recent studies indicate that cell dynamics play instrumental roles in neural pattern refinement and progression, but the impact of cell behaviour and morphogenesis on neural specification is not understood. Here we combine 4D analysis of cell behaviours with dynamic quantification of proneural expression to uncover the construction of the zebrafish otic neurogenic domain. We identify pioneer cells expressing neurog1 outside the otic primordium that migrate and ingress into the epithelialising placode to become the first otic neuronal progenitors. Subsequently, neighbouring cells express neurog1 inside the placode, and apical symmetric divisions amplify the specified pool. Interestingly, pioneer cells delaminate shortly after ingression. Ablation experiments reveal that pioneer cells promote neurog1 expression in other otic cells. Finally, ingression relies on the epithelialisation timing controlled by FGF activity. We propose a novel view for otic neurogenesis integrating cell dynamics whereby ingression of pioneer cells instructs neuronal specification.

Article and author information

Author details

  1. Esteban Hoijman

    Department of Experimental and Health Sciences, Universitat Pompeu Fabra, Barcelona, Spain
    For correspondence
    esteban.hoijman@upf.edu
    Competing interests
    The authors declare that no competing interests exist.
  2. Laura Fargas

    Department of Experimental and Health Sciences, Universitat Pompeu Fabra, Barcelona, Spain
    Competing interests
    The authors declare that no competing interests exist.
  3. Patrick Blader

    Centre de Biologie du Développement, Université de Toulouse, Toulouse, France
    Competing interests
    The authors declare that no competing interests exist.
  4. Berta Alsina

    Department of Experimental and Health Sciences, Universitat Pompeu Fabra, Barcelona, Spain
    For correspondence
    berta.alsina@upf.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6997-1249

Funding

The Ministry of Economy and competitiveness of Spain (BFU2011-270006)

  • Berta Alsina

The ministry of Economy and Competitiveness of Spain (BFU2014-53203)

  • Berta Alsina

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 experiments conform to the guidelines from the European Community Directive and the Spanish legislation for the experimental use of animals. The protocols (AR081096P4 and AR081098P3) were approved by the Committee on the Ethics of Animal Experiments of the Parc de Recerca Biomèdica de Barcelona (PRBB), Spain.

Reviewing Editor

  1. Marianne Bronner, California Institute of Technology, United States

Publication history

  1. Received: January 28, 2017
  2. Accepted: May 23, 2017
  3. Accepted Manuscript published: May 24, 2017 (version 1)
  4. Version of Record published: June 19, 2017 (version 2)

Copyright

© 2017, Hoijman 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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