How do Plants initiate Immune Response to Invading Pathogens?

Scientists at The Sainsbury Laboratory (TSL) Norwich and the Max Planck Institute for Plant Breeding Research (Cologne) have been working on a new study that could help underpin future development of disease-resistant crops. While advances in genetics, genomics and proteomics have significantly advanced our understanding of how receptors in a plant cell can detect pathogen molecules, much less is known about the events that convert this recognition into a defence response.

Pathogen sensors work with support

Immune receptors which recognise pathogen virulence factors are usually nucleotide-binding, leucine-rich repeat (NLR) proteins. Most NLRs act as sensors, but some act as "helper" NLRs, often of the RPW8-like NLR (RNL) family, that support sensor NLR signalling. Many sensor NLRs also require EDS1 family proteins for signalling but how and why this family association is required has remained unclear.

Distinct signalling modules formed

The research teams found that RNLs NRG1 and ADR1 form two distinct signalling modules with the EDS1-family members EDS1-SAG101 or EDS1-PAD4, respectively. Furthermore, the association between NRG1 with EDS1-SAG101 only occurs upon effector recognition by sensor NLRs. This study confirms that specific associations are formed upon immune activation to orchestrate a defence response, a core genetic discovery potentially relevant to all flowering plants, thus relevant for the engineering of NLRs and the components required to develop robust disease resistance in plants.

Dr Joanna Feehan, co-first author based at TSL said: “It’s exciting to discover that these core immune signalling components are working together in plant defence. The next step will be uncovering how they work together, and what exactly they do to restrict pathogens.”

Professor Jonathan Jones, co-author and group leader at TSL said: “Plants carry an enormous diversity in their capacity to detect and respond to different pathogen molecules. To move recognition capacity from one plant to another in the interests of controlling crop disease, we may need to also move any potentially required signalling components and that is why fundamental understanding of these signalling mechanisms is so important. It's been a pleasure to work with the Parker lab on this, a collaboration initiated at the last big pre-COVID conference in our field in Glasgow 2019, which illustrates why scientific conferences are so important”

This project was co-led by Professor Jane Parker and co-authored by Dr Xinhua Sun and Dr Dimitry Lapin at the Max Planck Institute. Their work was supported by the Max-Planck Society and Deutsche Forschungsgemeinschaft grants SFB 680 and SFB-1403–414786233; DFG-ANR Trilateral "RADAR” grant and a Chinese Scholarship Council doctoral fellowship. Joanna Feehan's PhD work was supported by a core grant from the Gatsby Charitable foundation to TSL.

The paper “Pathogen effector recognition-dependent association of NRG1 with EDS1 and SAG101 in TNL receptor immunity” can be viewed online under the DOI 10.1038/s41467-021-23614-x.

Further information:

The Sainsbury Laboratory online

Max Planck Institute for Plant Breeding Research online