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bioRxiv · 10.1101/2021.11.30.470685

Chitin-induced systemic disease resistance in rice requires both OsCERK1 and OsCEBiP and is mediated via perturbation of cell-wall biogenesis in leaves

Abstract

O_LIChitin is a well-known elicitor of disease resistance whose recognition by plants is crucial to perceive fungal infections. Chitin can induce both a local immune response and a systemic disease resistance when provided as a supplement in soils. Unlike local immune responses, how chitin-induced systemic disease resistance is deployed has not been studied in detail. C_LIO_LIIn this study, we evaluated systemic disease resistance against the fungal pathogen Bipolaris oryzae by performing a transcriptome analysis and monitoring cell-wall composition in rice plants grown in chitin-supplemented soils. We also examined the local immune response to chitin by measuring the production of reactive oxygen species in leaves. C_LIO_LIChitins induced both local immune response and systemic disease resistance with differing requirements for the receptors OsCERK1 and OsCEBiP. Transcriptome analysis suggested that a perturbation in cell-wall biogenesis is involved in the induction of systemic disease resistance, an idea which was supported by the induction of disease resistance by treatment with a cellulose biosynthesis inhibitor and alterations of cell-wall composition. C_LIO_LIThese findings suggest that chitin-induced systemic disease resistance in rice is caused by a perturbation of cell-wall biogenesis in leaves through long-distance signalling after recognition of chitins by OsCERK1 and OsCEBiP. C_LI

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BibTeXRIS

Takagi, M., Hotamori, K., Naito, K., Matsukawa, S., Egusa, M., Nishizawa, Y., Kanno, Y., Seo, M., Ifuku, S., Mine, A., Kaminaka, H.. 2021-12-01. Chitin-induced systemic disease resistance in rice requires both OsCERK1 and OsCEBiP and is mediated via perturbation of cell-wall biogenesis in leaves. https://doi.org/10.1101/2021.11.30.470685

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