1. Developmental Biology
  2. Evolutionary Biology
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Wnt/β-catenin signaling is an evolutionarily conserved determinant of chordate dorsal organizer

  1. Iryna Kozmikova  Is a corresponding author
  2. Zbynek Kozmik
  1. Institute of Molecular Genetics of the ASCR, Czech Republic
Research Article
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Cite this article as: eLife 2020;9:e56817 doi: 10.7554/eLife.56817

Abstract

Deciphering the mechanisms of axis formation in amphioxus is a key step to understanding the evolution of chordate body plan. The current view is that Nodal signaling is the only factor promoting the dorsal axis specification in the amphioxus whereas Wnt/β-catenin signaling plays no role in this process. Here, we re-examined the role of Wnt/βcatenin signaling in the dorsal/ventral patterning of amphioxus embryo. We demonstrated that the spatial activity of Wnt/β-catenin signaling is located in presumptive dorsal cells from cleavage to gastrula stage, and provided functional evidence that Wnt/β-catenin signaling is necessary for the specification of dorsal cell fate in a stage-dependent manner. Microinjection of Wnt8 and Wnt11 mRNA induced ectopic dorsal axis in neurulae and larvae. Finally, we demonstrated that Nodal and Wnt/β-catenin signaling cooperate to promote the dorsal-specific gene expression in amphioxus gastrula. Our study reveals high evolutionary conservation of dorsal organizer formation in the chordate lineage.

Article and author information

Author details

  1. Iryna Kozmikova

    Laboratory of Transcriptional Regulation, Institute of Molecular Genetics of the ASCR, Prague, Czech Republic
    For correspondence
    kozmikova@img.cas.cz
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-7861-9802
  2. Zbynek Kozmik

    Laboratory of Transcriptional Regulation, Institute of Molecular Genetics of the ASCR, Prague, Czech Republic
    Competing interests
    The authors declare that no competing interests exist.

Funding

Grantová Agentura České Republiky (GACR 15-21285J)

  • Iryna Kozmikova

Grantová Agentura České Republiky (GACR 17-15374S)

  • Zbynek Kozmik

Ministerstvo Školství, Mládeže a Tělovýchovy (ERDF,project No. CZ.02.1.01/0.0/0.0/16_013/0001775)

  • Iryna Kozmikova

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

Reviewing Editor

  1. Roel Nusse, Stanford University, United States

Publication history

  1. Received: March 10, 2020
  2. Accepted: May 25, 2020
  3. Accepted Manuscript published: May 26, 2020 (version 1)
  4. Accepted Manuscript updated: May 27, 2020 (version 2)
  5. Version of Record published: June 12, 2020 (version 3)

Copyright

© 2020, Kozmikova & Kozmik

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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