The Regulation Of Triterpenoid Biosynthesis Induced By The Combination Of Elicitor And Suppression Subtractive Library Analysis Induced By The MeJA

Suspension-cultured cells of birch were be experimental materials in this paper, investigates the effects of single elicitor of MeJA, SA and NO (SNP) or simultaneous treatment of the elicitors on the accumulation of triterpene (total triterpene, oleanolic acid and betulin) and the activities of defense enzyme. Suppression subtractive hybridization was employed to construct MeJA induced suspension-cultured cells of birch subtractive library, screening of differentially expressed genes and carry out bioinformatic analysis and quantitative PCR validation, in order to reveal the molecular regulation mechanism of triterpenoids induced by MeJA and lay the foundation to birth genomics research.The results were as follows:Single elicitor of MeJA, SA and SNP can increase the accumulation of total triterpene, oleanolic acid and betulin significantly in suspension-cultured cells of birch, MeJA>SA>SNP, induced effects is best after24h, the accumulation of total triterpene increased26.07%,21.63%,14.30%respectively compare the conrtol, the accumulation of oleanolic acid increased277.41%,369.34%,55.61%respectively, the accumulation of betulin increased179.58%,44.42%,157.33%respectively. Simultaneous treatment of the elicitors is not conducive to the total triterpene content increased.Single elicitor of MeJA, SA and SNP can increase the activities of PAL and SOD. Treated with MeJA and MeJA+SNP can increase the activities of CAT, POD and APX. Treated with SA+SNP and MeJA+SA+SNP inhibit the activities of CAT, but the activities of POD have no change. All treatment increase the activities of APX except treated with MeJA+SA. All treatment inhibit the content of MDA except treated with SNP, MeJA+SA and SA+SNP. Treated with MeJA can increase the activities of NADPH significantly.The results of correlation analysis showed that, there were only the activities of CAT and the accumulation of triterpene up to a positive correlation, the CAT to become the indicator enzyme of the accumulation of triterpene, then SOD. The APX, SOD, CAT and POD in scavenging reactive oxygen species coordinated and complement, and ultimately lead to the change of the accumulation of secondary product.MeJA induced suspension-cultured cells of birch forward subtractive library was constructed successfully. GO functional classification of the results showed that methyl jasmonate induced gene expression the antioxidant activity, catalytic activity, signal transduction activity, translation regulation activity. The catalytic activity of enzymes gene largest number, accounting for39.82%.Analysis the obtained27ESTs with Quantitative PCR. The results showed that27ESTs were five kinds of expression pattern, there were16genes at12h and24h upregulated and downregulated at48h, accounting for59.26%; there were6genes upregulated at12h and downregulated at24h and48h; there were3genes downregulated at12h,24h and48h; there were only one gene upregulated at12h,24h and48h, upregulated at12h and48h and downregulated at24h respectively.