Prediction of CpG islands and functional verification on promoters of FPS, SS, SE in Eleutherococcus senticosus / 中草药

Objective: To obtain the distribution and functional activity of CpG islands in promoters of FPS, SS, and SE from Eleutherococcus Senticosus. Methods: Based on the promoter sequence of FPS, SS and SE, CpG islands were predicted by using EMBOSS and Li Lab. The functional verification of transformed Arabidopsis thaliana was mediated by Agrobacterium tumefaciens by using GUS and pCAMBIA1301 plasmid as the reporter gene and expression vector respectively. Results: Two CpG islands were found in FPS and SS promoter with the lengths of 520 bp, 218 bp and 108 bp, 103 bp, and three CpG islands in SE promoter in 290 bp, 119 bp and 149bp. The promoters of FPS, SS and SE all had promoter activities at different level, in which SS promoter was the highest one. Conclusion: The functional verification and distributions of CpG islands in the promoters area of FPS, SS, and SE were reported in this research at first time, which established the foundation for the methylation analysis of FPS, SS, and SE and the further studying of the mechanism expression regulation in E. Senticosus.

Analysis of transicriptomes and exploring flavonoid biosynthetic pathway genes in Lithocarpus polystachyus / 中国中药杂志

The sweet taste and health effect of Lithocarpus polystachyus are mainly related flavonoid. To obtain Lithocarpus transcriptome database and flavonoid biosynthesis-related genes, the RNA-Seq techology (Illumina HiSeq 4000) was used to sequence its transcriptome. Six Gb database was assembled after assembly steps, and 41 043 of L. polystachyus unigenes were obtained. With blasting them with 7 data banks, all unigenes were involved in 51 GO-terms and 237 metabolic pathways. And furthermore 28 genes of the flavonoid biosynthesis-related were found. After using the MicroSatallite, 18 161 SSR were obtained, the single-nucleotide-repeated was the richest at 7 346. These data represent abundant messages about transcripts and provide valuable genome data sources in molecular biology of L. polystachyus.

Gene cloning and expression level of bAS and their correlation with content of saponins in Eleutherococcus senticosus / 中草药

Objective: To clone β-amyrin synthase (bAS) gene from Eleutherococcus senticosus and analyze the effect of its expression on saponin contents. Methods: The sequence of cDNA of E. senticosus bAS was cloned by homologous cloning strategy. Quantitative real time PCR was developed to analyze the expression pattern of E. senticosus bAS gene. And E. senticosus saponin contents were measured by spectrophotometry method. Results: Length 1 223 and 1 226 bp of E. senticosus bAS1 and bAS2 genes were cloned. The results showed that bAS1 and bAS2 were expressed in the each growth period and every organ of E. senticosus, and the expression differed significantly (P < 0.05). bAS1 showed the highest expression when the plants were grown in germination stage, then rapidly depressed, and changed slightly in the end. The expression of bAS2 showed the characteristic of low-high-low. The expression of bAS1 in different organs of E. senticosus was constant, but the highest content of the expression of bAS2 was in the leaves. With the treatment of methyl jasmonate (MeJA), bAS2 expression has been significantly improved and bAS1 without a significant changing. There exists significantly positive correlation (P < 0.01) between the content of E. senticosus saponins and the expression levels of bAS2, and bAS1 without a significant difference. Conclusion: bAS2 may be a key enzyme gene in the biosynthesis of triterpenoid saponins.

Expression profiles analysis of two member of squaleneepoxidase gene family from Eleutherococcus senticosus / 中国中药杂志

In order to find the characteristics of two members of gene family of squaleneexpoxidase (SE) , a quantitative real time PCR method was developed to analyze the expression of Eleutherococcus senticosus SE1 and SE2 gene from different growth periods and in different organs. The result indicated that all the expression of SE2 more than SE1 in the whole growth period and organs of E. senticosus. And in the whole growth period, expression of SE1 showed a low-high-low characteristic. Both expression of SE2 and growth period showed the same trend. The lowest content of the expression was in the roots. SE1 expression have been improved more than SE2 when treated with MeJA. The expression of E. senticosus SE1 and saponins content had significantly positive correlation (P < 0.05) and the correlation coefficients was 0. 858, while the correlation was not significant for SE2. That indicated that SE1 played a key enzyme gene in the biosynthesis of triterpenoidsaponins