Segmentation of the zebrafish axial skeleton relies on notochord sheath cells and not on the segmentation clock
- University of Münster, Germany
- The Francis Crick Institute, United Kingdom
- Hubrecht Institute, Netherlands
- University College London, United Kingdom
- Instituto de Investigación en Biomedicina de Buenos Aires, Argentina
Abstract
Segmentation of the axial skeleton in amniotes depends on the segmentation clock which patterns the paraxial mesoderm and the sclerotome. While the segmentation clock clearly operates in teleosts, the role of the sclerotome in establishing the axial skeleton is unclear. We severely disrupt zebrafish paraxial segmentation, yet observe a largely normal segmentation process of the chordacentra. We demonstrate that axial entpd5+ notochord sheath cells are responsible for chordacentrum mineralization, and serve as a marker for axial segmentation. While autonomous within the notochord sheath, entpd5 expression and centrum formation show some plasticity and can respond to myotome pattern. These observations reveal for the first time the dynamics of notochord segmentation in a teleost, and are consistent with an autonomous patterning mechanism that is influenced, but not determined by adjacent paraxial mesoderm. This behavior is not consistent with a clock-type mechanism in the notochord.
Data availability
Modelling films and images for the virtual time lapse have been uploaded to a public server from the university of Münster.The code in order to reproduce the model has been submitted to E-life directly
Article and author information
Author details
Stefan Schulte-Merker
Funding
Cancer Research UK
- Rachna Narayanan
- Andrew Oates
Medical Research Council
- Rachna Narayanan
- Andrew Oates
Wellcome
- Guillaume Valentin
- Andrew Oates
Fondo para la Investigación Científica y Tecnológica
- Luis G Morelli
Deutsche Forschungsgemeinschaft
- Laura LLeras Forero
- Stefan Schulte-Merker
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: Animal experiments were approved by the Animal Experimentation Committee (DEC) of the Royal Netherlands Academy of Arts and Sciences and by the UK Home Office under PPL 70/7675
Copyright
© 2018, LLeras Forero 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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Segmentation of the zebrafish axial skeleton relies on notochord sheath cells and not on the segmentation clock
eLife 7:e33843.
https://doi.org/10.7554/eLife.33843
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