The AUX1-AFB1-CNGC14 module establishes a longitudinal root surface pH profile
- Charles University, Czech Republic
- Czech Academy of Sciences, Czech Republic
- Heinrich-Heine-University Düsseldorf, Germany
Abstract
Plant roots navigate in the soil environment following the gravity vector. Cell divisions in the meristem and rapid cell growth in the elongation zone propel the root tips through the soil. Actively elongating cells acidify their apoplast to enable cell wall extension by the activity of plasma membrane AHA H+-ATPases. The phytohormone auxin, central regulator of gravitropic response and root development, inhibits root cell growth, likely by rising the pH of the apoplast. However, the role of auxin in the regulation of the apoplastic pH gradient along the root tip is unclear. Here we show, by using an improved method for visualization and quantification of root surface pH, that the Arabidopsis thaliana root surface pH shows distinct acidic and alkaline zones, which are not primarily determined by the activity of AHA H+-ATPases. Instead, the distinct domain of alkaline pH in the root transition zone is controlled by a rapid auxin response module, consisting of the AUX1 auxin influx carrier, the AFB1 auxin co-receptor and the CNCG14 calcium channel. We demonstrate that the rapid auxin response pathway is required for an efficient navigation of the root tip.
Data availability
All the data used for the the manuscript are available at Zenodo.The statistics used and p-values are available as supplementary file.
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The AUX1-AFB1-CNGC14 module establishes a longitudinal root surface pH profile main figuresZenodo, doi: 10.5281/zenodo.8138861.
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The AUX1-AFB1-CNGC14 module establishes a longitudinal root surface pH profile supplementary figuresZenodo, doi: 10.5281/zenodo.8140893.
Article and author information
Author details
Funding
European Research Council (803048)
- Nelson BC Serre
- Daša Wernerová
- Pruthvi Vittal
- Shiv Mani Dubey
- Eva Medvecká
- Matyáš Fendrych
Deutsche Forschungsgemeinschaft (GR4559)
- Guido Grossmann
Deutsche Forschungsgemeinschaft (CRC1208)
- Guido Grossmann
EPLAS-EXC-2048/1 (390686111)
- Guido Grossmann
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2023, Serre 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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The AUX1-AFB1-CNGC14 module establishes a longitudinal root surface pH profile
eLife 12:e85193.
https://doi.org/10.7554/eLife.85193
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