Fluctuations of the transcription factor ATML1 generate the pattern of giant cells in the Arabidopsis sepal
- Cornell University, United States
- University of Cambridge, United Kingdom
- Univ Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRA, France
Abstract
Multicellular development produces patterns of specialized cell types. Yet, it is often unclear how individual cells within a field of identical cells initiate the patterning process. Using live imaging, quantitative image analyses and modeling, we show that during Arabidopsis thaliana sepal development, fluctuations in the concentration of the transcription factor ATML1 pattern a field of identical epidermal cells to differentiate into giant cells interspersed between smaller cells. We find that ATML1 is expressed in all epidermal cells. However, its level fluctuates in each of these cells. If ATML1 levels surpass a threshold during the G2 phase of the cell cycle, the cell will likely enter a state of endoreduplication and become giant. Otherwise the cell divides. Our results demonstrate a fluctuation-driven patterning mechanism for how cell fate decisions can be initiated through a random yet tightly regulated process.
Data availability
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Fluctuations of the transcription factor ATML1 generates the pattern of giant cells in the Arabidopsis sepal.Publicly available at Cyverse DOI 10.7946/P29G6M.
Article and author information
Author details
Pau Formosa-Jordan
Adrienne HK Roeder
Funding
National Science Foundation (IOS-1553030)
- Adrienne HK Roeder
Gatsby Charitable Foundation (GAT3272/GLC)
- James CW Locke
Swedish Research Council (VR2013:4632)
- Henrik Jönsson
Herchel Smith Foundation
- José Teles
National Science Foundation (IOS-1256733)
- Adrienne HK Roeder
Gatsby Charitable Foundation (GAT3395/PR4)
- Henrik Jönsson
Herchel Smith Foundation
- Pau Formosa-Jordan
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2017, Meyer 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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Fluctuations of the transcription factor ATML1 generate the pattern of giant cells in the Arabidopsis sepal
eLife 6:e19131.
https://doi.org/10.7554/eLife.19131
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