[Research of genes expression related to ginsenosides biosynthesis by methyl jasmonic acid in ginseng hair roots].

In order to obtain the expression of ginsenoside biosynthetic pathway related enzyme gene in ginseng hairy root under the control of elicitors, methyl jasmonate (MeJA) was added exogenously as elicitors. Ginseng hairy root clones induced by 4-year-old ginseng root was used as material, total saponin content in ginseng hairy root before and after MeJA treatment was determined by vanillin-sulfuric acid colorimetry, Meanwhile, relative expression of squalene synthase genes, squalene epoxidase genes, oxidized squalene cyclase genes, dammarenediol synthase genes, β-amyrin synthase genes, cycloartenol synthase genes before and after MeJA treatment were determined by Real-time PCR. The optimum conditions of MeJA which added to ginseng hairy root were obtained, the optimum additional concentration was 6×10⁻⁴ μmol•L⁻¹, the optimum additional time was 22 d, and the optimum action time was 5 d. The addition of MeJA could improve the enzymatic activity of peroxidase (PPD), catalase (CAT) and peroxidase (PPD) in ginseng hairy root. The expression of SQS，SQE，OSC，DS and β-AS genes of ginsenoside biosynthetic pathway increased significantly after MeJA treatment, while the change of CAS gene expression were not significant. The expression of key enzyme SQS，SQE，OSC，DS and β-AS genes in ginsenoside biosynthetic pathway was consistent with the changes of PPD，CAT，PPO enzymatic activity.