Plant immune and growth receptors share common signalling components but localise to distinct plasma membrane nanodomains
Abstract
Cell surface receptors govern a multitude of signalling pathways in multicellular organisms. In plants, prominent examples are the receptor kinases FLS2 and BRI1, which activate immunity and steroid-mediated growth, respectively. Intriguingly, despite inducing distinct signalling outputs, both receptors employ common downstream signalling components, which exist in plasma membrane (PM)-localised protein complexes. An important question is thus how these receptor complexes maintain signalling specificity. Live-cell imaging revealed that FLS2 and BRI1 form PM nanoclusters. Using single-particle tracking we could discriminate both cluster populations and we observed spatiotemporal separation between immune and growth signalling platforms. This finding was confirmed by visualising FLS2 and BRI1 within distinct PM nanodomains marked by specific remorin proteins and differential co-localisation with the cytoskeleton. Our results thus suggest that signalling specificity between these pathways may be explained by the spatial separation of FLS2 and BRI1 with their associated signalling components within dedicated PM nanodomains.
Article and author information
Author details
Funding
Gatsby Charitable Foundation
- Silke Robatzek
- Daniel MacLean
- Cyril Zipfel
H2020 European Research Council
- Cyril Zipfel
Deutsche Forschungsgemeinschaft
- Thomas Ott
Universitat Bayern
- Iris Katharina Jarsch
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Thorsten Nürnberger, University of Tubingen, Germany
Version history
- Received: January 13, 2017
- Accepted: March 4, 2017
- Accepted Manuscript published: March 6, 2017 (version 1)
- Version of Record published: April 6, 2017 (version 2)
Copyright
© 2017, Bücherl 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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