Overexpression of tomato polyphenol oxidase increases resistance to common cutworm
Overexpression of tomato polyphenol oxidase increases resistance to common cutworm
复制标题
DOI：
10.1016/j.plantsci.2008.01.006
复制
发表时间：
2008-04-01
期刊：
影响因子：
5.2
通讯作者：
Thipyapong, Piyada
中科院分区：
文献类型：
--
作者：
Mahanil, Siraprapa;Attajarusit, Jutharat;Thipyapong, Piyada
据报道，多酚氧化酶（PPO）可催化酚类物质氧化成醌，赋予其对丁香假单胞菌的抗性，并被认为与昆虫抗性有关。为了评估 PPO 表达对地老虎 (Spodoptera litura (F.))（鳞翅目：夜蛾科）抗性的影响，我们使用了组成型表达正义和反义马铃薯 PPO 基因的转基因番茄 (Lycopersicon esculentum Mill.) 植物。表达有义 PPO 构建体的转基因植物（过表达 PPO [OP] 植物）表现出比非转化对照高 2.0-5.7 倍的 PPO 活性水平，而反义 PPO 转基因植物（抑制 PPO [SP] 植物）表现出比未转化对照低 1.5-7.3 倍的 PPO 活性水平。 PPO过表达的转基因植物明显表现出抗性的增加；普通地老虎在 OP 植物上的简单生长率分别比对照和 SP 叶子低 2.5 倍和 3.3 倍，而且幼虫消耗的叶子也更少。此外，PPO 活性增加导致幼虫死亡率更高。研究发现，具有不同 PPO 活性水平的番茄基因型之间，摄入食物的转化效率和第三龄消化食物的转化效率存在显着差异，表明 PPO 活性导致叶子营养成分降低。此外，当SP、NT和OP植物的节4和8处的小叶脱落并喂给地老虎幼虫时，它们的PPO活性水平被诱导1.6-2.2倍。这些结果表明 PPO 介导的酚氧化在抵抗这种昆虫方面发挥着关键作用。操纵 PPO 活性可以同时提供对病虫害的抵抗力，因此可以用作有效的综合害虫管理的组成部分。 (C) 2008 Elsevier Ireland Ltd. 保留所有权利。
Polyphenol oxidases (PPOs), which catalyze the oxidation of phenolics to quinones, have been reported to confer resistance to Pseudomonas syringae and are thought to be involved in insect resistance. To assess the impact of PPO expression on resistance to the common cutworm (Spodoptera litura (F.)) (Lepidoptera: Noctuidae), we used transgenic tomato (Lycopersicon esculentum Mill.) plants constitutively expressing sense- and antisense-oriented potato PPO genes. Transgenic plants expressing a sense PPO construct (overexpressing PPO [OP] plants) exhibited 2.0-5.7-fold higher PPO activity levels, whereas antisense PPO transgenic plants (suppressed PPO [SP] plants) exhibited 1.5-7.3-fold lower PPO activity levels than nontransformed controls. The PPO-overexpressing transgenic plants clearly showed an increase in resistance; simple growth rates of common cutworms on OP plants were up to 2.5 and 3.3 times lower than on controls and SP leaves, respectively, and larvae consumed less foliage. In addition, increased PPO activity led to higher larval mortality. The efficiency of conversion of ingested food and efficiency of conversion of digested food of third instars were found to be significantly different among tomato genotypes with differing PPO activity levels, suggesting that PPO activity rendered foliage less nutritious. Moreover, when leaflets at nodes 4 and 8 of SP, NT and OP plants were detached and fed to common cutworm larvae, their PPO activity levels were induced 1.6-2.2-fold. These results suggest a critical role for PPO-mediated phenolic oxidation in resistance to this insect. Manipulation of PPO activity could provide resistance simultaneously to both disease and insect pests, and therefore might be used as a component of effective integrated pest management. (C) 2008 Elsevier Ireland Ltd. All rights reserved.