Wnt/β-catenin regulates an ancient signaling network during zebrafish scale development
Understanding how patterning influences cell behaviors to generate three dimensional morphologies is a central goal of developmental biology. Additionally, comparing these regulatory mechanisms among morphologically diverse tissues allows for rigorous testing of evolutionary hypotheses. Zebrafish skin is endowed with a coat of precisely patterned bony scales. We use in-toto live imaging during scale development and manipulations of cell signaling activity to elucidate core features of scale patterning and morphogenesis. These analyses show that scale development requires the concerted activity of Wnt/β-catenin, Ectodysplasin (Eda) and Fibroblast growth factor (Fgf) signaling. This regulatory module coordinates Hedgehog (HH) dependent collective cell migration during epidermal invagination, a cell behavior not previously implicated in skin appendage morphogenesis. Our analyses demonstrate the utility of zebrafish scale development as a tractable system in which to elucidate mechanisms of developmental patterning and morphogenesis, and suggest a single, ancient origin of skin appendage patterning mechanisms in vertebrates.
All data generated or analyzed during this study are included in the manuscript and supporting files. Specialized materials including transgenic and mutant lines are available upon request.
Article and author information
National Institutes of Health (R35 GM122471)
- David M Parichy
Royalty Research Fund (A112414)
- David M Parichy
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All of the animals were handled according to approved Animal Care and Use Committee (ACUC) protocols (#4170) of the University of Virginia. All imaging and regeneration experiments were performed under MS222 anesthesi , and every effort was made to minimize suffering.
- Richard M White, Memorial Sloan Kettering Cancer Center, United States
- Received: March 26, 2018
- Accepted: June 21, 2018
- Accepted Manuscript published: July 17, 2018 (version 1)
- Version of Record published: August 2, 2018 (version 2)
© 2018, Aman 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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