Background : Although Oplopana elatus is a valuable medicinal plant that, like ginseng, recommends itself as source of herbal preparations, little molecular information on this plant is available. Therefore, to analyze the terpenoid biosynthetic pathway in O. elatus, we employed an RNA-seq approach. Methods and Results : To generate a transcriptome library of O. elatus, total RNA was extracted from different tissues, including leaves, stem, and root. A pooled RNA sample was prepared by combining equivalent RNA from different tissues. Using pair-end read with the Illumina platform, a total of 78,646,554 raw sequencing reads were generated. After data cleaning, approximately 77 million high-quality reads were obtained with 98% G20 (base quality of greater than 20). The high-quality reads were assembled into 208,959 unigenes with an average length of 1,073 bp and an N50 of 1,768 bp. Consistent with our prediction, which was based on the KEGG pathway assignment, we found 122 unigenes encoding 47 putative enzymes involved in the biosynthesis of terpenoid and triterpenoid saponins in the O. elatus transcriptome library. Conclusion : The transcriptome dataset generated in this study will serve as a valuable resource for accelerating genomic and functional genomic research in O. elatus and in the family Araliaceae.

Background : Even though Kalopanax septemlobus has been used as a traditional crude drug and a dietary health supplement, the wild or cultivated sources of this plant are not economically feasible. Methods and Results : In this study, a cell suspension culture of K. septemlobus using friable calli was established to make source sustainable. A cell suspension culture of K. septemlobus was incubated during 15th day and reached the maximum capacity of saponin production after day 6 (0.42㎍/㎎ of fresh weight). To investigate the effect of elicitors on the product yield of saponins in the K. septemlobus suspension culture, we treated methyl-jasmonic acid and coronatine (COR), which are known as signal molecules. COR positively regulates the total saponin production in the cell suspension of K. septemlobus at a concentration of 1 μM compared with the mock-treated control. Furthermore, the expression of beta-amyrin synthase (KsbAS) was induced by elicitation of COR. Consequently, oleanane-type triterpene saponins, oleanolic acid (2.369 ± 0.98 ㎍/㎎ of extract) were accumulated by only COR. Conclusion : From the above results, COR is an efficient elicitor for inducing saponin biosynthesis in a K. septemlobus suspension culture. Gene expression pattern and analysing precursor of triterpenoid saponin indicate that major target gene of COR in K. septemlobus suspension culture is KsbAS.