Investigation Of Synergistic Action Between Jasmonic Acid And Nitric Oxide In Inducing Matrine Accumulation Of Sophora Flavescens Ait Suppension Cells

Low production of bioactive compounds in cultured plant cells is one of the main limitations for commercial application of plant cell culture technology. The key for producing bioactive compounds in large-scale using plant cell culture technology is to improve the production of the desired metabolites. Biosynthesis of plant secondary metabolites has been well characterized to be mediated by endogenous signaling. However, the molecular basis of the signaling-mediated production of secondary metabolites is largely unknown. Jamoinc acid (JA) and nitric oxide (NO) are two important signaling molecules in plants, which have been documented to play key roles in defense responses of plants to multiple biotic and abiotic stresses. In order to investigate the roles and relationship/interaction between NO and JA in inducing plant secondary metabolite biosynthesis, we examined the effects of NO and JA on matrine production of Sophora flavescens Ait. suspension cells and assayed the interaction of JA and NO in inducing matrine biosynthesis. The main results are belows:1. JA triggers matrine production in dose-dependent manner.The matrine production of Sophora flavescens cells treated with100μmol/L JA are significantly increased as compared with the control, showing that J A is a potent inducer for matrine production of the cells. The effects of JA concentrations on matrine production of Sophora flavescens cells are determined. Matrine production of the cells increases relatively with the enhancement of JA concentrations within50-200μmol/L, but low concentrations of JA (≤10μmol/L) have no effects on matrine production of the cells, showing that JA induces matrine production of Sophora flavescens cells in dose-dependent manner.2. NO induces matrine production of the cells.Sodium nitroprusside (SNP) is a frequently used NO donor in plants, we investigate the effect of NO on the production of matrine. The results show that NO stimulates matrine production in dose-dependent manner, low concentrations of NO(≤0.1mmol/L SNP) have no effect on matrine production, and high concentration of NO(≥0.5mmol/L SNP) can remarkably trigger matrine productoion.3. Synergistic action between JA and NO in inducing matrine production.Matrine production of the cells treated with10μmol/L JA and0.05 mmol/L SNP is significantly enhanced, though treatment with0.05mmol/L SNP and10μmol/L JA alone has no effects on matrine production of the cells, showing that JA and SNP may act synergistically to induce matrine production of Sophora flavescens cells.4.The mutually amplifying reactions between JA and NO.In order to investigate the mechanism of the synergistic action between JA and NO in inducing matrine production, we determine JA contents and lipoxygenase (LOX) activities of Sophora flavescens cells treated with SNP. The results show that JA contents and LOX activities of the cells treated with0.05mmol/L SNP are significantly increased as compared with the control, showing that SNP may trigger the endogenous JA biosynthesis of the cells. Similarly, NO levels of the cells treated with10μmol/L JA are significantly increased as compared with the control. Furthermore, nitric oxide synthase (NOS)-like activity is induced by JA in Sophora flavescens cells.Together, the data demonstrate mutually amplifying reactions between JA and NO in the cells.5.The synergistic action of JA and NO in inducing matrine production is dependent on the mutually amplifying reactions between JA and NO.To investigate whether the synergistic action of JA and NO in inducing matrine production are caused by the mutually amplifying reactions between JA and NO. We measure the effect of the JA and NO inhibitors on their mutually amplifying reactions and on inducing the production of matrine, the results show that JA and NO inhibitors not only suppress the NO-induced JA biosynthesis and the JA-triggered NO generation of the cells respectively but also inhibit the synergistic effects between JA and NO on matrine production, which suggests that the synergistic action of JA and NO in inducing matrine accumulation is at least partially dependent on the mutually amplifying reactions between JA and NO.