Cell type boundaries organize plant development
In plants the dorsoventral boundary of leaves defines an axis of symmetry through the centre of the organ separating the top (dorsal) and bottom (ventral) tissues. Although the positioning of this boundary is critical for leaf morphogenesis, how the boundary is established and how it influences development remains unclear. Using live-imaging and perturbation experiments we show that leaf orientation, morphology and position are pre-patterned by HD-ZIPIII and KAN gene expression in the shoot, leading to a model in which dorsoventral genes coordinate to regulate plant development by localizing auxin response between their expression domains. However we also find that auxin levels feedback on dorsoventral patterning by spatially organizing HD-ZIPIII and KAN expression in the shoot periphery. By demonstrating that the regulation of these genes by auxin also governs their response to wounds, our results also provide a parsimonious explanation for the influence of wounds on leaf dorsoventrality.
Article and author information
H2020 European Research Council (261081)
- Marcus G Heisler
Marie Curie Actions (255089)
- Pia Sappl
Gordon and Betty Moore Foundation (GBMF3406)
- Elliot M Meyerowitz
Gatsby Charitable Foundation (GAT3395/PR4)
- Henrik Jönsson
Swedish Research Council (VR2013-4632)
- Henrik Jönsson
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Dominique C Bergmann, Stanford University/HHMI, United States
- Received: April 3, 2017
- Accepted: September 11, 2017
- Accepted Manuscript published: September 12, 2017 (version 1)
- Accepted Manuscript updated: September 25, 2017 (version 2)
- Version of Record published: September 27, 2017 (version 3)
© 2017, Caggiano 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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