The AtrbohD-Mediated Oxidative Burst Elicited by Oligogalacturonides in Arabidopsis Is Dispensable for the Activation of Defense Responses Effective against Botrytis cinerea
The AtrbohD-Mediated Oxidative Burst Elicited by Oligogalacturonides in Arabidopsis Is Dispensable for the Activation of Defense Responses Effective against Botrytis cinerea
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DOI：
10.1104/pp.108.127845
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发表时间：
2008-11-01
期刊：
影响因子：
7.4
通讯作者：
Ferrari, Simone
中科院分区：
文献类型：
--
作者：
Galletti, Roberta;Denoux, Carine;Ferrari, Simone
寡聚半乳糖醛酸（OGs）是植物细胞壁中果胶部分降解后释放的防御反应的内源激发子。我们以前已经表明，在拟南芥（拟南芥），OGs诱导的植物生长素缺乏症3（PAD 3）的表达和增加抗坏死型真菌病原体灰葡萄孢的茉莉酸，水杨酸和乙烯介导的信号转导途径独立。在这里，我们说明了快速诱导的各种基因的表达，由OG也是独立的水杨酸，乙烯，和茉莉酸。OG引起由NADPH氧化酶AtrbohD产生的强烈的细胞外氧化爆发。这种爆发对于OG-responsive基因的表达或OG-induced对B的抗性不是必需的。灰霉病，而胼胝质积累需要一个功能性的AtrbohD。OG-induced resistance to B.灰葡萄在白粉病抗性方面也不受影响4，尽管事实上在该突变体中胼胝质积累几乎被消除。这些结果表明，OG-induced氧化猝发是不需要的有效对抗B的防御反应的激活。灰霉病，留下开放的问题，活性氧在激发子介导的防御的作用。
Oligogalacturonides (OGs) are endogenous elicitors of defense responses released after partial degradation of pectin in the plant cell wall. We have previously shown that, in Arabidopsis (Arabidopsis thaliana), OGs induce the expression of PHYTOALEXIN DEFICIENT3 (PAD3) and increase resistance to the necrotrophic fungal pathogen Botrytis cinerea independently of signaling pathways mediated by jasmonate, salicylic acid, and ethylene. Here, we illustrate that the rapid induction of the expression of a variety of genes by OGs is also independent of salicylic acid, ethylene, and jasmonate. OGs elicit a robust extracellular oxidative burst that is generated by the NADPH oxidase AtrbohD. This burst is not required for the expression of OG-responsive genes or for OG-induced resistance to B. cinerea, whereas callose accumulation requires a functional AtrbohD. OG-induced resistance to B. cinerea is also unaffected in powdery mildew resistant4, despite the fact that callose accumulation was almost abolished in this mutant. These results indicate that the OG-induced oxidative burst is not required for the activation of defense responses effective against B. cinerea, leaving open the question of the role of reactive oxygen species in elicitor-mediated defense.