An N-terminal motif in NLR immune receptors is functionally conserved across distantly related plant species
- The Sainsbury Laboratory, University of East Anglia, United Kingdom
- Imperial College London, United Kingdom
Abstract
The molecular codes underpinning the functions of plant NLR immune receptors are poorly understood. We used in vitro Mu transposition to generate a random truncation library and identify the minimal functional region of NLRs. We applied this method to NRC4—a helper NLR that functions with multiple sensor NLRs within a Solanaceae receptor network. This revealed that the NRC4 N-terminal 29 amino acids are sufficient to induce hypersensitive cell death. This region is defined by the consensus MADAxVSFxVxKLxxLLxxEx (MADA motif) that is conserved at the N-termini of NRC family proteins and ~20% of coiled-coil (CC)-type plant NLRs. The MADA motif matches the N-terminal a1 helix of Arabidopsis NLR protein ZAR1, which undergoes a conformational switch during resistosome activation. Immunoassays revealed that the MADA motif is functionally conserved across NLRs from distantly related plant species. NRC-dependent sensor NLRs lack MADA sequences indicating that this motif has degenerated in sensor NLRs over evolutionary time.
Data availability
All sequence data used for bioinformatic and phylogenetic analyses are included in the manuscript and supporting files
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The Sol Genomics Network (SGN)--from genotype to phenotype to breedingTomato ITAG release 2.40 and N. benthamiana Genome v0.4.4.
Article and author information
Author details
Funding
Gatsby Charitable Foundation
- Sophien Kamoun
Biotechnology and Biological Sciences Research Council
- Sophien Kamoun
European Research Council
- Sophien Kamoun
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2019, Adachi 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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An N-terminal motif in NLR immune receptors is functionally conserved across distantly related plant species
eLife 8:e49956.
https://doi.org/10.7554/eLife.49956
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