De Vos Martin, Van Oosten Vivian R, Van Poecke Remco M P, Van Pelt Johan A, Pozo Maria J, Mueller Martin J, Buchala Antony J, Métraux Jean-Pierre, Van Loon L C, Dicke Marcel, Pieterse Corné M J
Graduate School Experimental Plant Sciences, Section Phytopathology, Department of Biology, Utrecht Faculty of Science, Utrecht University, P.O. Box 800.84, 3508 TB Utrecht, The Netherlands.
Mol Plant Microbe Interact. 2005 Sep;18(9):923-37. doi: 10.1094/MPMI-18-0923.
Plant defenses against pathogens and insects are regulated differentially by cross-communicating signaling pathways in which salicylic acid (SA), jasmonic acid (JA), and ethylene (ET) play key roles. To understand how plants integrate pathogen- and insect-induced signals into specific defense responses, we monitored the dynamics of SA, JA, and ET signaling in Arabidopsis after attack by a set of microbial pathogens and herbivorous insects with different modes of attack. Arabidopsis plants were exposed to a pathogenic leaf bacterium (Pseudomonas syringae pv. tomato), a pathogenic leaf fungus (Alternaria brassicicola), tissue-chewing caterpillars (Pieris rapae), cell-content-feeding thrips (Frankliniella occidentalis), or phloem-feeding aphids (Myzus persicae). Monitoring the signal signature in each plant-attacker combination showed that the kinetics of SA, JA, and ET production varies greatly in both quantity and timing. Analysis of global gene expression profiles demonstrated that the signal signature characteristic of each Arabidopsis-attacker combination is orchestrated into a surprisingly complex set of transcriptional alterations in which, in all cases, stress-related genes are overrepresented. Comparison of the transcript profiles revealed that consistent changes induced by pathogens and insects with very different modes of attack can show considerable overlap. Of all consistent changes induced by A. brassicicola, Pieris rapae, and E occidentalis, more than 50% also were induced consistently by P. syringae. Notably, although these four attackers all stimulated JA biosynthesis, the majority of the changes in JA-responsive gene expression were attacker specific. All together, our study shows that SA, JA, and ET play a primary role in the orchestration of the plant's defense response, but other regulatory mechanisms, such as pathway cross-talk or additional attacker-induced signals, eventually shape the highly complex attacker-specific defense response.
植物对病原体和昆虫的防御是由相互交叉通讯的信号通路差异调节的，其中水杨酸（SA）、茉莉酸（JA）和乙烯（ET）发挥着关键作用。为了了解植物如何将病原体和昆虫诱导的信号整合到特定的防御反应中，我们监测了拟南芥在受到一组具有不同攻击模式的微生物病原体和食草昆虫攻击后，SA、JA和ET信号的动态变化。拟南芥植株分别暴露于致病性叶细菌（丁香假单胞菌番茄致病变种）、致病性叶真菌（芸苔链格孢）、咀嚼组织的毛虫（粉纹夜蛾）、吸食细胞内容物的蓟马（西花蓟马）或吸食韧皮部的蚜虫（桃蚜）。监测每种植物-攻击者组合中的信号特征表明，SA、JA和ET产生的动力学在数量和时间上都有很大差异。对全局基因表达谱的分析表明，每种拟南芥-攻击者组合的信号特征被精心编排成一组惊人复杂的转录变化，在所有情况下，与胁迫相关的基因都占主导地位。转录谱的比较显示，具有非常不同攻击模式的病原体和昆虫诱导的一致变化可能会有相当大的重叠。在芸苔链格孢、粉纹夜蛾和西花蓟马诱导的所有一致变化中，超过50%也被丁香假单胞菌一致诱导。值得注意的是，尽管这四种攻击者都刺激了JA生物合成，但JA响应基因表达的大多数变化是攻击者特异性的。总之，我们的研究表明，SA、JA和ET在植物防御反应的编排中起主要作用，但其他调节机制，如信号通路间的相互作用或额外的攻击者诱导信号，最终塑造了高度复杂的攻击者特异性防御反应。
