Generation of the squamous epithelial roof of the 4th ventricle
Abstract
We use the transparency of zebrafish embryos to reveal the de novo generation of a simple squamous epithelium and identify the cellular architecture in the epithelial transition zone that ties this squamous epithelium to the columnar neuroepithelium within the embryo's brain. The simple squamous epithelium of the rhombencephalic roof plate is pioneered by distinct mesenchymal cells at the dorsal midline of the neural tube. Subsequently, a progenitor zone is established at the interface between columnar epithelium of the rhombic lip and the expanding squamous epithelium of the roof plate. Surprisingly, this interface consists of a single progenitor cell type that we have named the veil cell. Veil cells express gdf6a and constitute a lineage restricted stem zone that generates the squamous roof plate by direct transformation and asymmetrically fated divisions. Experimental restriction of roof plate expansion leads to extrusion of veil cell daughters and squamous cells, suggesting veil cell fate is regulated by the space available for roof plate growth.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files
Article and author information
Author details
Funding
Biotechnology and Biological Sciences Research Council (BB/I021507/1)
- Jonathan DW Clarke
- Richard JT Wingate
Wellcome
- Jonathan DW Clarke
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Tanya T Whitfield, University of Sheffield, United Kingdom
Ethics
Animal experimentation: This study was performed in strict accordance with the local ethics committee of King's College London and all animals handled according to the provisions of the Home Office UK Animals Scientific Procedures act 1986 (licence P70880F4C).
Version history
- Received: May 18, 2018
- Accepted: February 18, 2019
- Accepted Manuscript published: February 18, 2019 (version 1)
- Version of Record published: February 28, 2019 (version 2)
Copyright
© 2019, Campo-Paysaa 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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