Regulation of shoot meristem shape by photoperiodic signaling and phytohormones during floral induction of Arabidopsis
- Tokyo Metropolitan University, Japan
- Max Planck Institute for Plant Breeding Research, Germany
Abstract
Floral transition, the onset of plant reproduction, involves changes in shape and identity of the shoot apical meristem (SAM). The change in shape, termed doming, occurs early during floral transition when it is induced by environmental cues such as changes in day-length, but how it is regulated at the cellular level is unknown. We defined the morphological and cellular features of the SAM during floral transition of Arabidopsis thaliana. Both cell number and size increased during doming, and these changes were partially controlled by the gene regulatory network (GRN) that triggers flowering. Furthermore, dynamic modulation of expression of gibberellin biosynthesis and catabolism enzymes at the SAM contributed to doming. Expression of these enzymes was regulated by two MADS-domain transcription factors implicated in flowering. We provide a temporal and spatial framework for integrating the flowering GRN with cellular changes at the SAM, and highlight the role of local regulation of gibberellin.
Data availability
All data generated this study are included in the manuscript and supporting files. Source data files have been provided for Figures 1, 3, 6 and 7 and 8
Article and author information
Author details
Annabel D van Driel
Funding
Alexander von Humboldt-Stiftung
- Atsuko Kinoshita
Japanese Society for the promotion of Science
- Atsuko Kinoshita
Deutsche Forschungsgemeinschaft (390686111)
- George Coupland
Max-Planck-Gesellschaft (Open-access funding)
- George Coupland
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, Kinoshita 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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Regulation of shoot meristem shape by photoperiodic signaling and phytohormones during floral induction of Arabidopsis
eLife 9:e60661.
https://doi.org/10.7554/eLife.60661
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