Structures of plant resistosome reveal how NLR immune receptors are activated.

Nucleotide-binding domain and leucine-rich repeat (NLR) proteins make up the largest immune receptor family in plants. Although many studies have put effort into revealing the working mechanism of NLRs, the activation details of plant NLRs still remain obscure. Recently, two remarkable works resolved the structures of a plant NLR protein, the Arabidopsis thaliana HOPZ-ACTIVATED RESISTANCE1 (ZAR1), both in resting and activation states. The activated ZAR1 with its partner proteins form a wheel-like pentamer called resistosome that is thought to be able to trigger cell death by perturbing plasma membrane integrity. These findings greatly further our understanding of plant immune system.