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bioRxiv · 10.1101/2020.08.13.246413

Structure of the activated Roq1 resistosome directly recognizing the pathogen effector XopQ

Martin, R.·Qi, T.·Zhang, H.·Liu, F.·King, M.·Toth, C.·Nogales, E.·Staskawicz, B. J.
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Abstract

Plants and animals detect pathogen infection via intracellular nucleotide-binding leucine-rich repeat receptors (NLRs) that directly or indirectly recognize pathogen effectors and activate an immune response. How effector sensing triggers NLR activation remains poorly understood. Here we describe the 3.8 [A] resolution cryo-electron microscopy structure of the activated Roq1, an NLR native to Nicotiana benthamiana with a Toll-like interleukin-1 receptor (TIR) domain, bound to the Xanthomonas effector XopQ. Roq1 directly binds to both the predicted active site and surface residues of XopQ while forming a tetrameric resistosome that brings together the TIR domains for downstream immune signaling. Our results suggest a mechanism for the direct recognition of effectors by NLRs leading to the oligomerization-dependent activation of a plant resistosome and signaling by the TIR domain. One Sentence SummaryVisualization of an activated plant immune receptor that triggers the immune response upon pathogen recognition.

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Martin, R., Qi, T., Zhang, H., Liu, F., King, M., Toth, C., Nogales, E., Staskawicz, B. J.. 2020-08-14. Structure of the activated Roq1 resistosome directly recognizing the pathogen effector XopQ. https://doi.org/10.1101/2020.08.13.246413

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