Instituto de Investigaciones Químico-Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Michoacán, México.
PLoS One. 2011;6(11):e27251. doi: 10.1371/journal.pone.0027251. Epub 2011 Nov 4.
Alkamides are fatty acid amides of wide distribution in plants, structurally related to N-acyl-L-homoserine lactones (AHLs) from Gram-negative bacteria and to N- acylethanolamines (NAEs) from plants and mammals. Global analysis of gene expression changes in Arabidopsis thaliana in response to N-isobutyl decanamide, the most highly active alkamide identified to date, revealed an overrepresentation of defense-responsive transcriptional networks. In particular, genes encoding enzymes for jasmonic acid (JA) biosynthesis increased their expression, which occurred in parallel with JA, nitric oxide (NO) and H₂O₂ accumulation. The activity of the alkamide to confer resistance against the necrotizing fungus Botrytis cinerea was tested by inoculating Arabidopsis detached leaves with conidiospores and evaluating disease symptoms and fungal proliferation. N-isobutyl decanamide application significantly reduced necrosis caused by the pathogen and inhibited fungal proliferation. Arabidopsis mutants jar1 and coi1 altered in JA signaling and a MAP kinase mutant (mpk6), unlike salicylic acid- (SA) related mutant eds16/sid2-1, were unable to defend from fungal attack even when N-isobutyl decanamide was supplied, indicating that alkamides could modulate some necrotrophic-associated defense responses through JA-dependent and MPK6-regulated signaling pathways. Our results suggest a role of alkamides in plant immunity induction.
阿坎酰胺是广泛分布于植物中的脂肪酸酰胺，在结构上与革兰氏阴性细菌的 N-酰基高丝氨酸内酯 (AHLs) 和植物及哺乳动物的 N-酰基乙醇胺 (NAEs) 相关。对拟南芥中响应 N-异丁基癸酰胺（迄今为止鉴定出的最具活性的阿坎酰胺）的基因表达变化的全球分析显示，防御反应转录网络的代表性过高。特别是，编码茉莉酸 (JA) 生物合成酶的基因表达增加，这与 JA、一氧化氮 (NO) 和 H₂O₂ 的积累同时发生。通过用分生孢子接种拟南芥离体叶片并评估病害症状和真菌增殖来测试阿坎酰胺赋予对坏死真菌 Botrytis cinerea 的抗性的活性。N-异丁基癸酰胺的应用显著减少了病原体引起的坏死，并抑制了真菌的增殖。与水杨酸 (SA) 相关的突变体 eds16/sid2-1 不同，在 JA 信号传导中改变的 jar1 和 coi1 突变体以及 MAP 激酶突变体 (mpk6) 即使在施用 N-异丁基癸酰胺时也无法防御真菌攻击，表明阿坎酰胺可以通过 JA 依赖和 MPK6 调节的信号通路来调节一些与坏死相关的防御反应。我们的结果表明阿坎酰胺在植物免疫诱导中的作用。
