A Group D MAPK Protects Plants from Autotoxicity by Suppressing Herbivore-Induced Defense Signaling
A Group D MAPK Protects Plants from Autotoxicity by Suppressing Herbivore-Induced Defense Signaling
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D 组 MAPK 通过抑制食草动物诱导的信号传导来保护水稻免受自毒性
DOI：
10.1104/pp.18.01411
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发表时间：
2019-04-01
期刊：
影响因子：
7.4
通讯作者：
Lou, Yonggen
中科院分区：
文献类型：
--
作者：
Li, Jiancai;Liu, Xiaoli;Lou, Yonggen
植物激活和增强防御反应的机制已经得到了很好的研究；然而，使植物避免过度防御反应的调节机制尚不清楚。在这里，我们从水稻（Oryza sativa）中鉴定了一个组D分裂原激活蛋白激酶（MAPK）基因OsMAPK20-5，该基因的表达可被破坏性水稻害虫褐飞虱（Nilaparvata lugens）的妊娠雌性成虫侵染而快速诱导，而不受褐飞虱若虫侵染。沉默OsMAPK20-5 （irMAPK）的表达增加了雌性BPH受精卵侵染后乙烯和一氧化氮（NO）的积累，从而提高水稻对BPH成虫和产卵的抗性。然而，当暴露于高密度的雌性妊娠BPH时，irMAPK植株比野生型植株更早枯萎，这可能是由于irMAPK植株中乙烯和NO的过度积累。有趣的是，当释放到田间时，irMAPK植物对BPH和白背飞虱（Sogatella furcifera）这两种最具破坏性的水稻害虫表现出广泛的抗性，并产生了更高的产量。综上所述，我们的研究表明，尽管OsMAPK20-5可以降低水稻对飞虱的抗性，但它也可以使水稻控制过度的防御反应，从而防止防御反应相关的自毒性。
The mechanisms by which plants activate and enhance defense responses have been well studied; however, the regulatory mechanisms that allow plants to avoid excessive defense responses are poorly understood. Here, we identified a group D mitogen-activated protein kinase (MAPK) gene from rice (Oryza sativa), OsMAPK20-5, whose expression was rapidly induced by infestation of gravid female adults of a destructive rice pest, brown planthopper (BPH, Nilaparvata lugens), but not by BPH nymphs. Expression silencing of OsMAPK20-5 (irMAPK) increased the accumulation of ethylene and nitric oxide (NO) after gravid female BPH infestation, and thereby increased rice plant resistance to BPH adults and oviposited eggs. However, when exposed to high densities of gravid BPH females, irMAPK plants wilted earlier than wild-type plants, which could be attributed to the hyperaccumulation of ethylene and NO in irMAPK plants. Interestingly, when released into the field, irMAPK plants displayed broad resistance to BPH and white-backed planthopper (Sogatella furcifera), the two most destructive pests of rice, and produced higher yield. Taken together, our study shows that although OsMAPK20-5 can reduce the resistance of rice plants to planthoppers, it also enables rice plants to control excessive defense responses and thereby prevents defense-response-related autotoxicity.