Yu Yongchen, Qian Xiaona, Li Xiwang, Chai Zhichao, Ni Dejiang, Sun Xiaoling
Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310008, China.
Key Laboratory of Biology, Genetics and Breeding of Special Economic Animals and Plants, Ministry of Agriculture and Rural Affairs, Hangzhou 310008, China.
Int J Mol Sci. 2025 Apr 29;26(9):4248. doi: 10.3390/ijms26094248.
The jasmonic acid (JA) signaling pathway has been demonstrated to play a crucial role in plant defense against herbivorous insects. However, the relationship between -induced defensive metabolites and the JA signaling pathway in tea plants remains poorly understood. In this study, we investigated seven key special metabolites, including -coumaroylputrescine, feruloylputrescine, prunin, naringenin, and three monolignols, to address this knowledge gap. Epicatechin was selected as a positive control based on its well-documented regulation through the JA signaling pathway. Notably, the content of all selected compounds was significantly increased by infestation. Furthermore, exogenous application of high-dose methyl jasmonate (MeJA) induced the accumulation of six of the eight compounds, excluding -coumaryl alcohol and sinapyl alcohol, whereas low-dose MeJA failed to elicit their accumulation. To confirm the results, we screened two bioactive molecules, D-allose and L-theanine, which significantly increased the endogenous JA levels at low concentrations. Interestingly, neither D-allose nor L-theanine triggered the biosynthesis of these defensive compounds. Additionally, D-allose-treated tea leaves had no significant effect on the performance of larvae. These findings demonstrate that the metabolic accumulation induced by is mediated through a high-threshold JA signaling cascade. This study provides novel insights into the relationship between plant resistance and JA signaling pathway, advancing our understanding of special metabolites mediated plant-insect interactions.
茉莉酸（JA）信号通路已被证明在植物抵御食草昆虫方面发挥着关键作用。然而，茶树中诱导产生的防御性代谢产物与JA信号通路之间的关系仍知之甚少。在本研究中，我们研究了七种关键的特殊代谢产物，包括香豆酰腐胺、阿魏酰腐胺、樱草苷、柚皮素和三种单木质醇，以填补这一知识空白。基于其通过JA信号通路的明确调控，表儿茶素被选为阳性对照。值得注意的是，所有选定化合物的含量在虫害侵袭后均显著增加。此外，外源施用高剂量茉莉酸甲酯（MeJA）诱导了八种化合物中的六种的积累，不包括对香豆醇和芥子醇，而低剂量MeJA未能引发它们的积累。为了证实结果，我们筛选了两种生物活性分子，D-阿洛糖和L-茶氨酸，它们在低浓度下显著提高了内源性JA水平。有趣的是，D-阿洛糖和L-茶氨酸均未触发这些防御性化合物的生物合成。此外，D-阿洛糖处理的茶叶对幼虫的表现没有显著影响。这些发现表明，虫害诱导的代谢积累是通过高阈值JA信号级联介导的。本研究为植物抗性与JA信号通路之间的关系提供了新的见解，推进了我们对特殊代谢产物介导的植物-昆虫相互作用的理解。
