Groupe de Recherche en Physiologie Végétale-GRPV, Earth and Life Institute-Agronomy-ELI-A, Université Catholique de Louvain, 5 Bte 13 Place Croix du Sud, B-1348 Louvain-La-Neuve, Belgium.
J Plant Physiol. 2012 Jul 15;169(11):1090-101. doi: 10.1016/j.jplph.2012.03.015. Epub 2012 Jun 3.
Oxylipins have been extensively studied in plant defense mechanisms or as signal molecules. Depending on the stress origin (e.g. wounding, insect, pathogen), and also on the plant species or organ, a specific oxylipin signature can be generated. Salt stress is frequently associated with secondary stress such as oxidative damage. Little is known about the damage caused to lipids under salt stress conditions, especially with respect to oxylipins. In order to determine if an organ-specific oxylipin signature could be observed during salt stress, tomato (Solanum lycopersicum cv. Money Maker) plants were submitted to salt stress (100 mM of NaCl) for a 30-d period. A complete oxylipin profiling and LOX related-gene expression measurement were achieved in leaves and roots. As expected, salt stress provoked premature senescence in leaves, as revealed by a decrease in photosystem II efficiency (F(v)/F(m) ratio) and sodium accumulation in leaves. In roots, a significant decrease in several oxylipins (9- and 13-hydro(pero)xy linole(n)ic acids, keto and divinyl ether derivatives) was initiated at day 5 and intensified at day 21 after salt treatment, whereas jasmonic acid content increased. In leaves, the main changes in oxylipins were observed later (at day 30), with an increase in some 9- and 13-hydro(pero)xy linole(n)ic acids and a decrease in some keto-derivatives and in jasmonic acid. Oxylipin enantiomeric characterization revealed that almost all compounds were formed enzymatically, and therefore a massive auto-oxidation of lipids that can be encountered in abscission processes can be excluded here.
氧化脂类在植物防御机制或作为信号分子方面已经得到了广泛的研究。根据应激源（例如，创伤、昆虫、病原体）的不同，以及植物物种或器官的不同，可以产生特定的氧化脂类特征。盐胁迫通常与氧化损伤等次生胁迫有关。关于盐胁迫条件下脂质所受到的损伤，特别是关于氧化脂类的损伤，人们知之甚少。为了确定在盐胁迫期间是否可以观察到器官特异性氧化脂类特征，将番茄（Solanum lycopersicum cv. Money Maker）植株置于盐胁迫（100 mM NaCl）下 30 天。在叶片和根系中实现了完整的氧化脂类分析和 LOX 相关基因表达测量。正如预期的那样，盐胁迫导致叶片过早衰老，表现为光合系统 II 效率（Fv/Fm 比值）下降和叶片中钠离子积累。在根中，几种氧化脂类（9-和 13-羟基（过）亚油酸（linolenic acids）、酮和二乙烯基醚衍生物）在盐处理后第 5 天开始显著减少，并在第 21 天加剧，而茉莉酸含量增加。在叶片中，氧化脂类的主要变化发生较晚（第 30 天），一些 9-和 13-羟基（过）亚油酸增加，一些酮衍生物和茉莉酸减少。氧化脂类的对映体特征表明，几乎所有化合物都是酶促形成的，因此可以排除在此过程中遇到的脂质大规模自动氧化。
