Plant Immune Receptor Dynamics and Pathogen Recognition

Plants rely on a multilayered immune system in which cell-surface and intracellular receptors detect conserved microbial patterns and rapidly evolving virulence proteins known as effectors. Central to intracellular recognition are nucleotide‐binding leucine‐rich repeat receptors (NLRs), which fluctuate between inactive and active conformations in response to effector binding. Many NLRs assemble into sensor–helper pairs or larger networks, enabling signal amplification and fine‐tuning of defence outputs. Pathogens counter these defences by evolving effectors that disrupt receptor activation or downstream signalling. A subset of NLRs employs integrated domains—additional protein modules fused to canonical NLR architecture—to mimic genuine effector targets and serve as decoys for direct detection. Structural dynamics of these receptors, together with coevolutionary arms races, underpin the specificity and durability of plant resistance. Recent advances in structural prediction, synthetic biology and receptor engineering have begun to reveal how receptor surfaces and integrated domains orchestrate effector recognition and immune activation, offering routes to design disease‐resistant crops.

Research from Nature Portfolio

Recent studies have leveraged high‐throughput structural modelling to chart the diversity of fungal phytopathogen effectors and trace their evolutionary origins. By predicting and comparing more than eighteen thousand secreted protein structures across multiple species, researchers uncovered lineage‐specific expansions of sequence‐unrelated yet structurally similar effector families and identified ancestral folds conserved across fungi. These insights reveal how structural convergence and divergent evolution generate novel effector functions and refine our understanding of pathogen adaptability. In parallel, structure‐guided mutagenesis of a rice sensor NLR demonstrated that multiple interaction surfaces both within an integrated heavy metal‐associated domain and its flanking regions are essential for binding distinct blast fungus effectors and triggering helper‐dependent resistance. This work underscores the requirement for concerted interfaces in sensor NLRs and points to rational approaches for engineering receptors with broadened recognition profiles.

Plant Immune Receptor Dynamics and Pathogen Recognition publication trend

The graph below shows the total number of articles in plant immune receptor dynamics and pathogen recognition across all publications each year (not limited to Nature Index journals).

Technical terms

Nucleotide‐binding leucine‐rich repeat receptor (NLR): A modular intracellular receptor that switches from ADP‐bound inactive to ATP‐bound active states upon effector detection, initiating immune signalling.

Effector: A pathogen‐secreted protein that manipulates host physiology, often to suppress immunity; recognised directly or indirectly by plant receptors.

Integrated domain (ID): A non‐canonical protein module fused into an NLR, typically mimicking effector targets to serve as built‐in baits or decoys.

Sensor–helper NLR pair: A functional duo in which one NLR (sensor) detects effectors and the other (helper) transduces or amplifies defence signals.

Integrated decoy model: A concept in which host proteins targeted by effectors are duplicated and fused into NLRs to enable direct recognition and immune activation.

Co‐evolution: Reciprocal genetic adaptation between plants and pathogens, driving diversification of both effectors and immune receptors.

References

1. Prediction of effector protein structures from fungal phytopathogens enables evolutionary analyses. Nature Microbiology (2023).
2. The synthetic NLR RGA5HMA5 requires multiple interfaces within and outside the integrated domain for effector recognition. Nature Communications (2024).
3. The integrated LIM-peptidase domain of the CSA1-CHS3/DAR4 paired immune receptor detects changes in DA1 peptidase inhibitors in Arabidopsis. Cell Host & Microbe (2023).
4. Allelic compatibility in plant immune receptors facilitates engineering of new effector recognition specificities. The Plant Cell (2023).
5. Bioengineering a plant NLR immune receptor with a robust binding interface toward a conserved fungal pathogen effector. Proceedings of the National Academy of Sciences of the United States of America (2024).