9CC8

Hexameric state of the NRC4 resistosome

Summary for 9CC8

• Entry DOI: 10.2210/pdb9cc8/pdb
• EMDB information: 45437
• Descriptor: NLR-required for cell death 4, ADENOSINE-5'-TRIPHOSPHATE (2 entities in total)
• Functional Keywords: plant resistosome, plant protein
• Biological source: Nicotiana benthamiana
• Total number of polymer chains: 6
• Total formula weight: 603491.26

Authors

Liu, F.,Yang, Z.,Nogales, E.,Staskawicz, B.J. (deposition date: 2024-06-21, release date: 2024-09-11, Last modification date: 2024-09-18)

Primary citation

Liu, F.,Yang, Z.,Wang, C.,You, Z.,Martin, R.,Qiao, W.,Huang, J.,Jacob, P.,Dangl, J.L.,Carette, J.E.,Luan, S.,Nogales, E.,Staskawicz, B.J.
Activation of the helper NRC4 immune receptor forms a hexameric resistosome.
Cell, 187:4877-4889.e15, 2024

PubMed Abstract: Innate immune responses to microbial pathogens are regulated by intracellular receptors known as nucleotide-binding leucine-rich repeat receptors (NLRs) in both the plant and animal kingdoms. Across plant innate immune systems, "helper" NLRs (hNLRs) work in coordination with "sensor" NLRs (sNLRs) to modulate disease resistance signaling pathways. Activation mechanisms of hNLRs based on structures are unknown. Our research reveals that the hNLR, known as NLR required for cell death 4 (NRC4), assembles into a hexameric resistosome upon activation by the sNLR Bs2 and the pathogenic effector AvrBs2. This conformational change triggers immune responses by facilitating the influx of calcium ions (Ca) into the cytosol. The activation mimic alleles of NRC2, NRC3, or NRC4 alone did not induce Ca influx and cell death in animal cells, suggesting that unknown plant-specific factors regulate NRCs' activation in plants. These findings significantly advance our understanding of the regulatory mechanisms governing plant immune responses.

PubMed: 39094568
DOI: 10.1016/j.cell.2024.07.013

Experimental method

ELECTRON MICROSCOPY (2.66 Å)