Why plants make puzzle cells, and how their shape emerges
- Max Planck Institute for Plant Breeding Research, Germany
- Cornell University, United States
- Université de Lyon, France
- Stockholm University, Sweden
- University of Calgary, Canada
Abstract
The shape and function of plant cells are often highly interdependent. The puzzle-shaped cells that appear in the epidermis of many plants are a striking example of a complex cell shape, however their functional benefit has remained elusive. We propose that these intricate forms provide an effective strategy to reduce mechanical stress in the cell wall of the epidermis. When tissue-level growth is isotropic, we hypothesize that lobes emerge at the cellular level to prevent formation of large isodiametric cells that would bulge under the stress produced by turgor pressure. Data from various plant organs and species support the relationship between lobes and growth isotropy, which we test with mutants where growth direction is perturbed. Using simulation models we show that a mechanism actively regulating cellular stress plausibly reproduces the development of epidermal cell shape. Together, our results suggest that mechanical stress is a key driver of cell-shape morphogenesis.
Article and author information
Author details
Adrienne HK Roeder
Funding
Swiss National Science Foundation (SystemsX.ch iPhD grant 2010/073)
- Richard S Smith
Bundesministerium für Bildung und Forschung (031A492)
- Richard S Smith
Human Frontier Science Program (RGP0008/2013)
- Chun-Biu Li
- Olivier Hamant
- Adrienne HK Roeder
- Richard S Smith
European Commission (Marie Skłodowska-Curie individual fellowship (Horizon 2020 703886))
- Adam Runions
Natural Science and Engineering Research Council of Canada (Discovery Grant RGPIN-2014-05325)
- Przemyslaw Prusinkiewicz
European Research Council (ERC-2013-CoG-615739 'MechanoDevo')
- Olivier Hamant
Max Planck Society (Core grant and open-access funding)
- Miltos Tsiantis
- Richard S Smith
Bundesministerium für Bildung und Forschung (031A494)
- Richard S Smith
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Sapala 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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Why plants make puzzle cells, and how their shape emerges
eLife 7:e32794.
https://doi.org/10.7554/eLife.32794
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