Roles for mannitol and mannitol dehydrogenase in active oxygen-mediated plant defense
Roles for mannitol and mannitol dehydrogenase in active oxygen-mediated plant defense
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DOI：
10.1073/pnas.95.25.15129
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发表时间：
1998-12-08
影响因子：
11.1
通讯作者：
Williamson, JD
中科院分区：
文献类型：
--
作者：
Jennings, DB;Ehrenshaft, M;Williamson, JD
活性氧（Reactive oxygen species，ROS）是植物防御病原菌的信号分子和直接参与者。许多真菌合成甘露醇，一种有效的ROS淬灭剂，并且越来越多的证据表明至少一些植物病原真菌使用甘露醇来抑制ROS介导的植物防御。在这里，我们显示诱导甘露醇生产和分泌的植物病原真菌链格孢在宿主植物提取物的存在下。相反，我们表明，分解代谢酶甘露醇脱氢酶在不产生甘露醇的植物中被诱导，以响应真菌感染和植物防御反应的特定诱导剂。这提供了一种机制，由此植物可以通过分解代谢真菌来源的甘露醇来抵消真菌对ROS介导的防御的抑制。
Reactive oxygen species (ROS) are both signal molecules and direct participants in plant defense against pathogens. Many fungi synthesize mannitol, a potent quencher of ROS, and there is growing evidence that at least some phytopathogenic fungi use mannitol to suppress ROS-mediated plant defenses. Here we show induction of mannitol production and secretion in the phytopathogenic fungus Alternaria alternata in the presence of host-plant extracts. Conversely, we show that the catabolic enzyme mannitol dehydrogenase is induced in a non-mannitol-producing plant in response to both fungal infection and specific inducers of plant defense responses. This provides a mechanism whereby the plant can counteract fungal suppression of ROS-mediated defenses by catabolizing mannitol of fungal origin.