Hydrogen peroxide and jasmonic acid mediate oligogalacturonic acid-induced saponin accumulation in suspension-cultured cells of Panax ginseng
Hydrogen peroxide and jasmonic acid mediate oligogalacturonic acid-induced saponin accumulation in suspension-cultured cells of Panax ginseng
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DOI：
10.1034/j.1399-3054.2003.00124.x
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发表时间：
2003-07-01
影响因子：
6.4
通讯作者：
Tang, ZC
中科院分区：
文献类型：
--
作者：
Hu, XY;Neill, S;Tang, ZC
人参悬浮培养诱导的防御反应的信号通路。A. Meyer，通过植物细胞壁来源的激发子寡聚半乳糖醛酸（OGA），进行了研究。OGA可能通过NADPH氧化酶样酶诱导过氧化氢（H2 O2）的快速产生和释放。此外，OGA引起茉莉酸（JA）和防御化合物皂苷的积累，以及编码皂苷生物合成的关键酶角鲨烯合酶（SQS; EC 2.5.1.21）和角鲨烯环氧酶（SQE; EC 1.14.99.7）的基因的表达。H-2 O-2和JA也诱导了sqs和sqe的转录和皂甙的积累. JA的积累，但不是H2 O2的积累，抑制JA生物合成的抑制剂，而H2 O2和JA的积累抑制处理，去除H2 O2或抑制其产生。此外，H2 O2刺激JA积累，但JA处理对H2 O2的产生没有影响。这些数据将H2 O2和JA作为细胞应答中的早期信号传导中间体，介导响应于OGA的皂苷生物合成，并将H2 O2定位在JA的上游。钙通量和蛋白质磷酸化的抑制剂在一定程度上抑制了所有的反应，表明在导致皂苷积累的信号级联中的至少一个步骤中需要蛋白激酶和钙。
The signalling pathways mediating defence responses induced in suspension cultures of ginseng, Panax ginseng C. A. Meyer, by the plant cell wall-derived elicitor oligogalacturonic acid (OGA), were investigated. OGA induced the rapid generation and release of hydrogen peroxide, H2O2, potentially via an NADPH oxidase-like enzyme. In addition, OGA elicited the accumulation of jasmonic acid (JA) and the defence compound saponin, and expression of genes encoding squalene synthase (SQS; EC 2.5.1.21) and squalene epoxidase (SQE; EC 1.14.99.7), key enzymes of saponin biosynthesis. H-2 O-2 and JA also induced saponin accumulation and transcription of sqs and sqe . The accumulation of JA, but not that of H2O2, was inhibited by an inhibitor of JA biosynthesis, whereas the accumulation of both H2O2 and JA were inhibited by treatments that removed H2O2 or inhibited its production. Moreover, H2O2 stimulated JA accumulation, but JA treatment had no effect on H2O2 generation. These data place H2O2 and JA as early signalling intermediaries in the cellular responses mediating saponin biosynthesis in response to OGA, and position H2O2 upstream of JA. Inhibitors of calcium fluxes and protein phosphorylation inhibited all responses to some extent, indicating the requirements for a protein kinase and calcium in at least one step in the signal cascade leading to saponin accumulation.