Plant signalling in symbiosis and immunity



Plants encounter a myriad of microorganisms, particularly at the root–soil interface, that can invade with detrimental or beneficial outcomes. Prevalent beneficial associations between plants and microorganisms include those that promote plant growth by facilitating the acquisition of limiting nutrients such as nitrogen and phosphorus. But while promoting such symbiotic relationships, plants must restrict the formation of pathogenic associations. Achieving this balance requires the perception of potential invading microorganisms through the signals that they produce, followed by the activation of either symbiotic responses that promote microbial colonization or immune responses that limit it.

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Figure 1: LysM-receptor-kinase complexes that are involved in the sensing of microorganisms.
Figure 2: Similarities between the N-acetylglucosamine-containing microbial molecules that are recognized by plants.
Figure 3: Plant immune and symbiotic intracellular signalling pathways.
Figure 4: Nodulation involves the dampening of plant defences.


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Research on this topic in the authors' laboratories is supported by: the Gatsby Charitable Foundation (C.Z.); the European Research Council (PHOSPHinnATE; C.Z.); the 2Blades Foundation (C.Z.); the UK Biotechnology and Biological Sciences Research Council (BB/J004553/1; C.Z. and G.O.); and the Bill and Melinda Gates Foundation (G.O.). The authors thank members of their laboratories for continuous discussions and P. Kalo for providing the images presented in Fig. 4. We apologize to our colleagues whose work could not be cited owing to space limitations.

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Reviewer Information Nature thanks B. Thomma, J. Dangl and the other anonymous reviewer(s) for their contribution to the peer review of this work.

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Zipfel, C., Oldroyd, G. Plant signalling in symbiosis and immunity. Nature 543, 328–336 (2017).

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