Organ geometry channels reproductive cell fate in the Arabidopsis ovule primordium
- IRD, CIRAD, France
- University of Zürich, Switzerland
- Institut de Recherche pour le Développement, France
- Université de Lyon, ENS de Lyon, France
- University of Lyon, ENS Lyon, UCB Lyon 1, CNRS, INRAE, INRIA, France
Abstract
In multicellular organisms, sexual reproduction requires the separation of the germline from the soma. In flowering plants, the female germline precursor differentiates as a single spore mother cell (SMC) as the ovule primordium forms. Here, we explored how organ growth contributes to SMC differentiation. We generated 92 annotated 3D images at cellular resolution in Arabidopsis. We identified the spatio-temporal pattern of cell division that acts in a domain-specific manner as the primordium forms. Tissue growth models uncovered plausible morphogenetic principles involving a spatially confined growth signal, differential mechanical properties, and cell growth anisotropy. Our analysis revealed that SMC characteristics first arise in more than one cell but SMC fate becomes progressively restricted to a single cell during organ growth. Altered primordium geometry coincided with a delay in the fate restriction process in katanin mutants. Altogether, our study suggests that tissue geometry channels reproductive cell fate in the Arabidopsis ovule primordium.
Data availability
The data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for all Figures. Segmented Image data are deposited in Dryad Digital Repository, available at: doi:10.5061/dryad.02v6wwq2c. Cell Statistics from these images are deposited as 'Segmented Dataset ...csv' at https://github.com/barouxlab/OvuleViz
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Arabidopsis ovule primordium stages 0-I to 2-II, wild-type Col_0, Ws-4 and botero (bot1-7) mutantDryad Digital Repository, doi:10.5061/dryad.02v6wwq2c.
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Segmented_Dataset_Hernandez_Mosca_etal_2020https://github.com/barouxlab/OvuleViz.
Article and author information
Author details
Elvira Hernandez-Lagana
Ethel Mendocilla-Sato
Funding
Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung (310030L_170167)
- Célia Baroux
Agence Nationale de la Recherche (16-CE93-0002)
- Daphné Autran
Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung (310030B_160336)
- Ueli Grossniklaus
Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung (IZCOZ0_182949)
- Célia Baroux
Kommission für Technologie und Innovation (16997)
- Célia Baroux
Baugarten Stiftung
- Célia Baroux
Consejo Nacional de Ciencia y Tecnología (438277)
- Elvira Hernandez-Lagana
Forschungskredit Universitaet Zuerich (FK-74502-04-01)
- Gabriella Mosca
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Hernandez-Lagana 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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