Zhejiang Provincial Key Laboratory for Genetic Improvement and Quality Control of Medical Plants, Hangzhou Normal University, Hangzhou, 310035, China.
Biotechnol Prog. 2013 Jul-Aug;29(4):994-1001. doi: 10.1002/btpr.1738. Epub 2013 May 2.
Elicitations are considered to be an important strategy to improve production of secondary metabolites of plant cell cultures. However, mechanisms responsible for the elicitor-induced production of secondary metabolites of plant cells have not yet been fully elucidated. Here, we report that treatment of Catharanthus roseus cell suspension cultures with PB90, a protein elicitor from Phytophthora boehmeriae, induced rapid increases of abscisic acid (ABA) and nitric oxide (NO), subsequently followed by the enhancement of catharanthine production and up-regulation of Str and Tdc, two important genes in catharanthine biosynthesis. PB90-induced catharanthine production and the gene expression were suppressed by the ABA inhibitor and NO scavenger respectively, showing that ABA and NO are essential for the elicitor-induced catharanthine biosynthesis. The relationship between ABA and NO in mediating catharanthine biosynthesis was further investigated. Treatment of the cells with ABA triggered NO accumulation and induced catharanthine production and up-regulation of Str and Tdc. ABA-induced catharanthine production and gene expressions were suppressed by the NO scavenger. Conversely, exogenous application of NO did not stimulate ABA generation and treatment with ABA inhibitor did not suppress NO-induced catharanthine production and gene expressions. Together, the results showed that both NO and ABA were involved in PB90-induced catharanthine biosynthesis of C. roseus cells. Furthermore, our data demonstrated that ABA acted upstream of NO in the signaling cascade leading to PB90-induced catharanthine biosynthesis of C. roseus cells.
激发子被认为是提高植物细胞培养物次生代谢产物产量的重要策略。然而，负责植物细胞激发子诱导次生代谢产物产生的机制尚未完全阐明。在这里，我们报告 PB90（来自疫霉菌的一种蛋白激发子）处理长春花悬浮细胞培养物可诱导脱落酸（ABA）和一氧化氮（NO）的快速增加，随后增强了长春质碱的产生，并上调了 Str 和 Tdc，这两个是长春质碱生物合成中的重要基因。ABA 抑制剂和 NO 清除剂分别抑制 PB90 诱导的长春质碱产生和基因表达，表明 ABA 和 NO 是激发子诱导长春质碱生物合成所必需的。进一步研究了 ABA 和 NO 在介导长春质碱生物合成中的关系。用 ABA 处理细胞会引发 NO 积累，并诱导长春质碱的产生和 Str 和 Tdc 的上调。NO 清除剂抑制 ABA 诱导的长春质碱产生和基因表达。相反，外源施加的 NO 不会刺激 ABA 的产生，而 ABA 抑制剂处理不会抑制 NO 诱导的长春质碱产生和基因表达。总之，结果表明，NO 和 ABA 都参与了 PB90 诱导的长春花细胞长春质碱生物合成。此外，我们的数据表明，在 PB90 诱导长春花细胞长春质碱生物合成的信号级联中，ABA 在前，NO 在后。
