jasmonic-acid and lanthanum-chloride

Rare earth elements (REEs) have been widely used to increase accumulation of biomass and secondary metabolites in medicinal plants in China. However, very few studies have investigated how REEs mediate secondary metabolism synthesis in medicinal plants. Lanthanum (La), an important REE, is known to improve the accumulation of secondary metabolites in medicinal plants and is widely distributed in China. However, few studies have evaluated the signal transduction leading to La-induced secondary metabolism in medicinal plants. In this study, LaCl(3) treatment-induced multiple responses in Scutellaria baicalensis seedlings, including the rapid generation of jasmonic acid (JA), sequentially followed by the enhancement of baicalin production. Direct application of JA also promoted the synthesis of baicalin in the absence of LaCl(3). LaCl(3)-induced baicalin synthesis was blocked by two different JA synthesis inhibitors. Our results showed that JA acts as a signal component within the signaling system leading to La-induced baicalin synthesis in S. baicalensis seedlings.

Topics: Cyclopentanes; Flavonoids; Lanthanum; Oxylipins; Scutellaria baicalensis; Seedlings

Cerebrosides, compounds categorized as glycosphingolipids, were found to occur in a wide range of phytopathogens as novel elicitors and to induce the effective disease resistance for rice plants in our previous study. Here, we showed that cerebroside elicitors lead to the accumulation of phytoalexins and pathogenesis-related (PR) protein in cell suspension cultures of rice with the structural specificity similar to that for the rice whole plants. This elicitor activity of the cerebroside was greater than jasmonic acid (JA) and chitin oligomer (which is known to be an elicitor for cell suspension cultures of rice). Treatment of cell suspension cultures with cerebroside and chitin oligomer resulted in a synergetic induction of phytoalexins, suggesting that cerebroside and carbohydrate elicitors, such as glucan and chitin elicitor, enhance the defense signals of rice in vivo. Induction of phytoalexins by the treatment with cerebroside elicitor was markedly inhibited by LaCl(3) and GdCl(3), Ca(2+ )channel blockers. It is possible that Ca(2+) may be involved in the signaling pathway of elicitor activity of cerebroside.

Topics: Calcium Channel Blockers; Calmodulin; Cells, Cultured; Cerebrosides; Chitin; Cyclopentanes; Drug Synergism; Gadolinium; Immunity, Innate; Lanthanum; Oryza; Oxylipins; Phosphoprotein Phosphatases; Phytoalexins; Plant Extracts; Plant Proteins; Sesquiterpenes; Signal Transduction; Sphingolipids; Terpenes