Cultivar-specific avirulence and virulence functions assigned to avrPphF in Pseudomonas syringae pv. phaseolicola, the cause of bean halo-blight disease
Cultivar-specific avirulence and virulence functions assigned to avrPphF in Pseudomonas syringae pv. phaseolicola, the cause of bean halo-blight disease
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DOI：
10.1093/emboj/19.13.3204
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发表时间：
2000-07-03
期刊：
影响因子：
11.4
通讯作者：
Murillo, J
中科院分区：
文献类型：
--
作者：
Tsiamis, G;Mansfield, JW;Murillo, J
avrPphF基因是从菜豆生假单胞菌致病变种（Pph）小种5和7中克隆的，基于其赋予对携带用于抗晕枯病的R1基因的菜豆栽培品种（例如墨西哥红）无毒力的能力。avrPphF包含两个开放阅读框，这两个开放阅读框都是功能所必需的，并且位于Pph中的154 kb质粒（pAV 511）上，缺乏pAV 511的Pph菌株RW 60显示出对一系列先前敏感的品种如Tendergreen和Canadian Wonder的毒力丧失。在Tendergreen中，仅通过avrPphF恢复RW60的毒力，而在pAV 511不存在的情况下亚克隆的avrPphF大大加速了由RW60引起的过敏性抗性反应。来自pAV 511的第二个基因avrPphC控制对大豆的无毒力，发现其在加拿大奇迹中阻断avrPphF的活性，但在墨西哥红中不阻断。avrPphF还在大豆中赋予毒力。avrPphF的多种功能说明了植物病原体的效应蛋白如何进化为被R基因产物识别，因此被归类为无毒基因编码。
The avrPphF gene was cloned from Pseudomonas syringae pathovar phaseolicola (Pph) races 5 and 7, based on its ability to confer avirulence towards bean cultivars carrying the R1 gene for halo-blight resistance, such as Red Mexican. avrPphF comprised two open reading frames, which were both required for function, and was located on a 154 kb plasmid (pAV511) in Pph, Strain RW60 of Pph, lacking pAV511, displayed a loss in virulence to a range of previously susceptible cultivars such as Tendergreen and Canadian Wonder. In Tendergreen virulence was restored to RW60 by avrPphF alone, whereas subcloned avrPphF in the absence of pAV511 greatly accelerated the hypersensitive resistance reaction caused by RW60 in Canadian Wonder. A second gene from pAV511, avrPphC, which controls avirulence to soybean, was found to block the activity of avrPphF in Canadian Wonder, but not in Red Mexican. avrPphF also conferred virulence in soybean. The multiple functions of avrPphF illustrate how effector proteins from plant pathogens have evolved to be recognized by R gene products and, therefore, be classified as encoded by avirulence genes.