Activation and inhibition mechanisms of a plant helper NLR.
Xiao, Y., Wu, X., Wang, Z., Ji, K., Zhao, Y., Zhang, Y., Wan, L.(2025) Nature
- PubMed: 39939758
- DOI: https://doi.org/10.1038/s41586-024-08517-3
- Primary Citation of Related Structures:
8YL6, 8YL7 - PubMed Abstract:
Plant nucleotide-binding leucine-rich repeat (NLR) receptors sense pathogen effectors and form resistosomes to confer immunity 1 . Some sensor NLR resistosomes produce small molecules to induce formation of a heterotrimer complex with two lipase-like proteins, EDS1 and SAG101, and a helper NLR called NRG1 (refs. 2,3 ). Activation of sensor NLR resistosomes also triggers NRG1 oligomerization and resistosome formation at the plasma membrane 4,5 . We demonstrate that the Arabidopsis AtEDS1-AtSAG101-AtNRG1A heterotrimer formation is stabilized by the AtNRG1A loss-of-oligomerization mutant L134E 5,6 . We report structures of AtEDS1-AtSAG101-AtNRG1A L134E and AtEDS1-AtSAG101-AtNRG1C heterotrimers with similar assembly mechanisms. AtNRG1A signalling is activated by the interaction with the AtEDS1-AtSAG101 heterodimer in complex with their small-molecule ligand. The truncated AtNRG1C maintains core interacting domains of AtNRG1A but develops further interactions with AtEDS1-AtSAG101 to outcompete AtNRG1A. Moreover, AtNRG1C lacks an N-terminal signalling domain and shows nucleocytoplasmic localization, facilitating its sequestration of AtEDS1-AtSAG101, which is also nucleocytoplasmic. Our study shows the activation and inhibition mechanisms of a plant helper NLR.
Organizational Affiliation:
State Key Laboratory of Plant Trait Design, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China.