Distribution of neurosensory progenitor pools during inner ear morphogenesis unveiled by cell lineage reconstruction
Abstract
Reconstructing the lineage of cells is central to understanding how the wide diversity of cell types develops. Here, we provide the neurosensory lineage reconstruction of a complex sensory organ, the inner ear, by imaging zebrafish embryos in vivo over an extended timespan, combining cell tracing and cell fate marker expression over time. We deliver the first dynamic map of early neuronal and sensory progenitor pools in the whole otic vesicle. It highlights the remodeling of the neuronal progenitor domain upon neuroblast delamination, and reveals that the order and place of neuroblasts' delamination from the otic epithelium prefigure their position within the SAG. Sensory and non-sensory domains harbor different proliferative activity contributing distinctly to the overall growth of the structure. Therefore, the otic vesicle case exemplifies a generic morphogenetic process where spatial and temporal cues regulate cell fate and functional organization of the rudiment of the definitive organ.
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Funding
Ministerio de Economía y Competitividad (BFU2012-31994)
- Cristina Pujades
Unidad de Excelencia María de Maetzu (2015-19 MDM-2014-0370 to DCEXS-UPF)
- Sylvia Dyballa
- Andrea Zecca
- Cristina Pujades
Centro de Excelencia Severo Ochoa (2013-17 SEV-2012-0208 to CRG)
- Philipp Germann
Agence Nationale de la Recherche (ANR-10-INBS-04)
- Nadine Peyriéras
Agence Nationale de la Recherche (ANR-11-EQPX-0029)
- Nadine Peyriéras
Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung (SINERGIA CRSII3 141918)
- Philipp Germann
Becas de la Generalitat de Catalunya (Predoctoral FI-fellowship)
- Sylvia Dyballa
- Andrea Zecca
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: This study was performed in strict accordance with the European Regulations. Zebrafish embryos were obtained by mating of adult fish using standard methods. All fish strains were maintained individually as inbred lines. All protocols used have been approved by the Institutional Animal Care and Use Ethic Committee (PRBB-IACUEC), and implemented according to national and European regulations. All experiments were carried out in accordance with the principles of the 3Rs. All our experiments were carried out using the CPC16-008/9125 protocol approved by the Generalitat of Catalonia.
Copyright
© 2017, Dyballa 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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