Oxidative burst and cognate redox signalling reported by luciferase imaging: identification of a signal network that functions independently of ethylene, SA and Me-JA but is dependent on MAPKK activity
Oxidative burst and cognate redox signalling reported by luciferase imaging: identification of a signal network that functions independently of ethylene, SA and Me-JA but is dependent on MAPKK activity
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DOI：
10.1046/j.1365-313x.2000.00902.x
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发表时间：
2000-12-01
期刊：
影响因子：
7.2
通讯作者：
Loake, GJ
中科院分区：
文献类型：
--
作者：
Grant, JJ;Yun, BW;Loake, GJ
无毒微生物病原体的识别激活了氧化爆发，导致活性氧中间体（ROI）的积累，其被认为整合了多种多样的防御机制，导致植物抗病性的建立。一种新的转基因拟南芥品系含有gst 1：：luc转基因的开发和使用报告的时间和空间动态的ROI积累和同源氧化还原信号的尝试感染假单胞菌pv.番茄（Pst）。强参与的氧化爆发是依赖于存在的功能性Pst hrpS和hrpA基因产物。采用药理学试剂的实验表明，至少有两种不同的来源，包括NADPH氧化酶和过氧化物酶型酶，有助于产生氧化还原线索。在nahG，coi1和etr1植物中的gst1和pall基因表达的分析表明，参与的氧化爆发和同源氧化还原信号功能独立的水杨酸，茉莉酸甲酯和乙烯。相反，在这些突变体背景中使用一组蛋白激酶和磷酸酶抑制剂以及凝胶内激酶测定的研究表明，48 kDa的促分裂原活化蛋白激酶（MAPK）活性是响应氧化还原信号而激活gst 1和pal 1所必需的。因此，具有MAPK模块的分叉氧化还原信号通路的参与可能有助于植物抗病性的建立和细胞保护剂机制的发展。
Recognition of avirulent microbial pathogens activates an oxidative burst leading to the accumulation of reactive oxygen intermediates (ROIs), which are thought to integrate a diverse set of defence mechanisms resulting in the establishment of plant disease resistance. A novel transgenic Arabidopsis line containing a gst1::luc transgene was developed and employed to report the temporal and spatial dynamics of ROI accumulation and cognate redox signalling in response to attempted infection by avirulent strains of Pseudomonas syringae pv. tomato (Pst). Strong engagement of the oxidative burst was dependent on the presence of functional Pst hrpS and hrpA gene products. Experiments employing pharmacological agents suggested that at least two distinct sources, including an NADPH oxidase and a peroxidase-type enzyme, contributed to the generation of redox cues. The analysis of gst1 and pall gene expression in nahG, coi1 and etr1 plants suggested that engagement of the oxidative burst and cognate redox signalling functioned independently of salicylic acid, methyl jasmonate and ethylene. in contrast, studies using a panel of protein kinase and phosphatase inhibitors and in-gel kinase assays in these mutant backgrounds suggested that a 48 kDa mitogen-activated protein kinase (MAPK) activity was required for the activation of gst1 and pal1 in response to redox cues. Thus the engagement of a bifurcating redox signalling pathway possessing a MAPK module may contribute both to the establishment of plant disease resistance, and to the development of cellular protectant mechanisms.