Control of plant cell fate transitions by transcriptional and hormonal signals
- Heidelberg University, Germany
- University of California, San Diego, United States
Abstract
Plant meristems carry pools of continuously active stem cells, whose activity is controlled by developmental and environmental signals. After stem cell division, daughter cells that exit the stem cell domain acquire transit amplifying cell identity before they are incorporated into organs and differentiate. In this study, we used an integrated approach to elucidate the role of HECATE (HEC) genes in regulating developmental trajectories of shoot stem cells in Arabidopsis thaliana. Our work reveals that HEC function stabilizes cell fate in distinct zones of the shoot meristem thereby controlling the spatio-temporal dynamics of stem cell differentiation. Importantly, this activity is concomitant with the local modulation of cellular responses to cytokinin and auxin, two key phytohormones regulating cell behaviour. Mechanistically, we show that HEC factors transcriptionally control and physically interact with MONOPTEROS (MP), a key regulator of auxin signalling, and modulate the autocatalytic stabilization of auxin signalling output.
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Funding
Deutsche Forschungsgemeinschaft (SFB873)
- Anna Marciniak-Czochra
- Jan U Lohmann
European Social Fund (Elite programm für Postdocs)
- Anne Pfeiffer
Baden-Württemberg Stiftung (Elite programm für Postdocs)
- Anne Pfeiffer
National Institutes of Health (1R01GM112976-01A1)
- Martin F Yanofsky
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2017, Gaillochet 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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