Defense gene induction in tobacco by nitric oxide, cyclic GMP, and cyclic ADP-ribose
Defense gene induction in tobacco by nitric oxide, cyclic GMP, and cyclic ADP-ribose
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DOI：
10.1073/pnas.95.17.10328
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发表时间：
1998-08-18
影响因子：
11.1
通讯作者：
Klessig, DF
中科院分区：
文献类型：
--
作者：
Durner, J;Wendehenne, D;Klessig, DF
活性氧被认为在植物对微生物攻击的防御反应中发挥多种作用，在最初的防御中起作用，并可能作为细胞信号分子。在动物中，一氧化氮（NO）是一种重要的氧化还原活性信号分子。在这里，我们表明，感染的抗性，但不敏感，烟草与烟草花叶病毒导致增强一氧化氮合酶（NOS）的活性。此外，管理NO供体或重组哺乳动物NOS烟草植物或烟草悬浮细胞触发的防御相关基因编码的病程相关蛋白1和苯丙氨酸解氨酶（PAL）的表达。这些基因也被环GMP（cGMP）和环ADP-核糖诱导，这两种分子可以作为哺乳动物中NO信号传导的第二信使。一致的是，Vith cGMP作为烟草中的第二信使，NO处理诱导内源性cGMP水平的急剧和短暂的增加。鸟苷酸环化酶抑制剂6-苯胺基-5，8-喹啉二酮和1H-（1，2，4）-恶二唑[4，3-a]喹喔啉-1-酮可阻断NO对PAL的激活作用。虽然6-苯胺基-5，8-喹啉二酮完全阻断PAL激活，但1H-（1，2，4）-恶二唑[4，3-a]喹喔啉-1-酮的抑制作用并不完全，表明存在cGMP依赖性和cGMP非依赖性NO信号传导。我们的结论是，动物NO信号的几个关键球员也在植物中运作。
Reactive oxygen species are believed to perform multiple roles during plant defense responses to microbial attack, acting in the initial defense and possibly as cellular signaling molecules. In animals, nitric oxide (NO) is an important redox-active signaling molecule. Here we show that infection of resistant, but not susceptible, tobacco with tobacco mosaic virus resulted in enhanced NO synthase (NOS) activity. Furthermore, administration of NO donors or recombinant mammalian NOS to tobacco plants or tobacco suspension cells triggered expression of the defense-related genes encoding pathogenesis-related 1 protein and phenylalanine ammonia lyase (PAL). These genes were also induced by cyclic GMP (cGMP) and cyclic ADP-ribose, two molecules that can serve as second messengers for NO signaling in mammals. Consistent,vith cGMP acting as a second messenger in tobacco, NO treatment induced dramatic and transient increases in endogenous cGMP levels. Furthermore, NO-induced activation of PAL was blocked by 6-anilino-5,8-quinolinedione and 1H-(1,2,4)-oxadiazole [4,3-a] quinoxalin-1-one, two inhibitors of guanylate cyclase. Although 6-anilino-5,8-quinolinedione fully blocked PAL activation, inhibition by 1H-(1,2,4)-oxadiazole [4,3-a] quinoxalin-1-one was not entirely complete, suggesting the existence of cGMP-independent, as well as cGMP-dependent, NO signaling. We conclude that several critical players of animal NO signaling are also operative in plants.