Jasmonates are ubiquitously occurring plant growth regulators with high structural diversity that mediate numerous developmental processes and stress responses. We have recently identified 12-O-β-D-glucopyranosyljasmonic acid as the bioactive metabolite, leaf-closing factor (LCF), which induced nyctinastic leaf closure of Samanea saman. We demonstrate that leaf closure of isolated Samanea pinnae is induced upon stereospecific recognition of (-)-LCF, but not by its enantiomer, (+)-ent-LCF, and that the nonglucosylated derivative, (-)-12-hydroxyjasmonic acid also displays weak activity. Similarly, rapid and cell type-specific shrinkage of extensor motor cell protoplasts was selectively initiated upon treatment with (-)-LCF, whereas flexor motor cell protoplasts did not respond. In these bioassays related to leaf movement, all other jasmonates tested were inactive, including jasmonic acid (JA) and the potent derivates JA-isoleucine and coronatine. By contrast, (-)-LCF and (-)-12-hydroxyjasmonic acid were completely inactive with respect to activation of typical JA responses, such as induction of JA-responsive genes LOX2 and OPCL1 in Arabidopsis (Arabidopsis thaliana) or accumulation of plant volatile organic compounds in S. saman and lima bean (Phaseolus lunatus), generally considered to be mediated by JA-isoleucine in a COI1-dependent fashion. Furthermore, application of selective inhibitors indicated that leaf movement in S. saman is mediated by rapid potassium fluxes initiated by opening of potassium-permeable channels. Collectively, our data point to the existence of at least two separate JA signaling pathways in S. saman and that 12-O-β-D-glucopyranosyljasmonic acid exerts its leaf-closing activity through a mechanism independent of the COI1-JAZ module.

中文翻译：

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12-羟基茉莉酸葡萄糖苷是一种不依赖 COI1-JAZ 的 Samanea saman 叶片闭合运动激活剂。

茉莉酸是无处不在的植物生长调节剂，具有高度的结构多样性，可调节多种发育过程和应激反应。我们最近鉴定了 12-O-β-D-吡喃葡萄糖基茉莉酮酸作为生物活性代谢物，即叶闭合因子 (LCF)，它诱导了 Samanea saman 的 nyctinastic 叶闭合。我们证明分离的 Samanea pinnae 的叶子闭合是由 (-)-LCF 的立体特异性识别诱导的，但不是由其对映异构体 (+)-ent-LCF 诱导的，并且非糖基化衍生物 (-)-12-羟基茉莉酮酸也显示活动较弱。同样，在用 (-)-LCF 处理后，伸肌运动细胞原生质体的快速和细胞类型特异性收缩被选择性地启动，而屈肌运动细胞原生质体没有反应。在这些与叶运动相关的生物测定中，测试的所有其他茉莉酸酯均无活性，包括茉莉酸 (JA) 和强效衍生物 JA-异亮氨酸和冠氨酸。相比之下，(-)-LCF 和 (-)-12-羟基茉莉酸在典型 JA 反应的激活方面完全无活性，例如在拟南芥中诱导 JA 反应基因 LOX2 和 OCL1 或植物的积累S. saman 和利马豆 (Phaseolus lunatus) 中的挥发性有机化合物，通常被认为是由 JA-异亮氨酸以 COI1 依赖性方式介导的。此外，选择性抑制剂的应用表明，S. saman 中的叶运动是由钾渗透通道打开引发的快速钾通量介导的。总的来说，我们的数据表明金黄色葡萄球菌中至少存在两个独立的 JA 信号通路。