Direct pathogen-induced assembly of an NLR immune receptor complex to form a holoenzyme
Ma ShouCai, Dmitry Lapin, Jie Liu, Yue Sun, Wen Song, Xiaoxiao Zhang, Elke Logemann, Dongli Yu, Jia Wang, Jan Jirschitzka, Zhifu Han, Paul Schulze‐Lefert, Jane E. Parker, Jijie Chai
Abstract
Tetrameric immune receptors Nucleotide-binding/leucine-rich repeat (NLR) immune receptors detect pathogen effectors and trigger a plant's immune response. Two groups have now defined the structures of two NLRs that carry Toll-like interleukin-1 receptor (TIR) domains (TIR-NLRs) (see the Perspective by Tian and Li). Ma et al. studied the Arabidopsis thaliana TIR-NLR RPP1 (recognition of Peronospora parasitica 1) and its response to effectors from an oomycete pathogen. Martin et al. studied the Nicotiana benthamiana TIR-NLR ROQ1 (recognition of XopQ 1) and its response to the Xanthomonas effector. Both groups found that these TIR-NLRs formed tetramers that, when activated by binding to the pathogen effector, exposed the active site of a nicotinamide adenine dinucleoside (NAD) hydrolase. Thus, recognition of the pathogen effector initiates NAD hydrolysis and begins the immune response. Science , this issue p. eabe3069 , p. eabd9993 ; see also p. 1163