关键词: 地黄, 次生代谢产物, 生物合成, 基因表达, 实时荧光定量PCR

Abstract: In order to study the relative expression of the biosynthetic genes for secondary metabolites in different materials of Rehmannia glutinosa, and analyze the relationship between gene expression and secondary metabolites accumulation, this paper extracted total RNA from leaves, leaves of tissue culture seeding and hairy roots of R. glutinosa, respectively. TIP41 was used as a reference gene, and the relative expression of the biosynthesis-related enzymes genes for catalpol and verbascoside were analyzed by real-time quantitative PCR. The content of catalpol and verbascoside in 3 kinds of material were measured by HPLC, respectively, while the content of total iridoid glycoside was measured by UV spectrophotometry, and then the correlation between their contents and relative expressions of the genes related to biosynthesis enzymes were analyzed. The results indicated that there were more differences in the expression levels of the genes related to biosynthesis enzyme for secondary metabolites and their contents among the 3 different kinds of R. glutinosa materials. According to relative correlation analysis, the content of catalpol was significantly and positively correlated with the expression quantity of GGPPS2, and the content of total iridoid glycoside was also significantly correlated with the expression quantities of GGPPS1 and G10H, indicating that GGPPS2 was related with the synthesis of catalpa, GGPPS1 and G10H might be related to total iridoid glycoside biosynthesis. While, there were no significant correlation between the content of verbascoside with the expression levels of ADT, ASP5, 4CL, C3H, HCT and GOT2. These results provided references for relative studies on secondary metabolites biosynthetic pathways of R. glutinosa.