Salicylic acid is part of the Mi-1-mediated defense response to root-knot nematode in tomato
Salicylic acid is part of the Mi-1-mediated defense response to root-knot nematode in tomato
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DOI：
10.1094/mpmi.2004.17.4.351
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发表时间：
2004-04-01
影响因子：
3.5
通讯作者：
Williamson, VM
中科院分区：
文献类型：
--
作者：
Branch, C;Hwang, CF;Williamson, VM
番茄Mi-1基因具有对番茄（Lycopersicon esculentum）三种根结线虫的抗性。用表达NahG的构建体转化携带Mi-1的番茄，NahG编码水杨酸羟化酶，一种将水杨酸（SA）降解为邻苯二酚的细菌酶，导致对根结线虫的抗性部分丧失。外源SA对表达NahG的根有毒害作用，但对对照根无毒害作用。这种毒性最有可能是由于从SA的儿茶酚的生产，我们在这里报告说，100 μ M儿茶酚是有毒的番茄根。苯并噻二唑，SA类似物，完全恢复线虫抗性Mi-1根转化NahG，但不赋予敏感的番茄根的抗性。NahG的共表达阻止了Mi-1与其同源物之一的组成型致死嵌合体Mi-DS 4在本氏烟草中瞬时表达所产生的局部细胞死亡。这些结果表明SA是导致线虫抗性和相关过敏反应的信号传导的重要组分。
The Mi-1 gene of tomato confers resistance against three species of root-knot nematode in tomato (Lycopersicon esculentum). Transformation of tomato carrying Mi-1 with a construct expressing NahG, which encodes salicylate hydroxylase, a bacterial enzyme that degrades salicyllic acid (SA) to catechol, results in partial loss of resistance to root-knot nematodes. Exogenous SA was toxic to roots expressing NahG but not to control roots. This toxicity is most likely due to the production of catechol from SA, and we report here that 100 muM catechol is toxic to tomato roots. Benzothiadiazole, a SA analog, completely restores nematode resistance in Mi-1 roots transformed with NahG but does not confer resistance to susceptible tomato roots. The localized cell death produced by transient expression in Nicotiana benthamiana of Mi-DS4, a constitutively lethal chimera of Mi-1 with one of its homologs, was prevented by coexpression of NahG. These results indicate that SA is an important component of the signaling that leads to nematode resistance and the associated hypersensitive response.