The Relationship Study Of Ecological Factors With Ginseng CYP716A52v2、CYP716A53v2 Gene Expression Levels And Saponins

Ginseng is an important genuineness herb in northeast China. Its main medicinal composition is ginsenoside, whose biosynthesis is co-regulated by environmental factors and key enzyme genes in regulatory biosynthesis. This study, cloned gene CYP716A52v2 and CYP716A53v2 of ginseng, conducted analysis on their bioinformatics and gene expression information, measured of ginseng saponins in different growth times, total saponin content and key enzyme gene expression amount, and analyzed the relationship between ecological factors and key enzymes gene expression amount. The main study contents are as follows:1.This experiment cloned and sequenced gene CYP716A52v2 and CYP716A53v2 that downstream pathway of ginsenoside biosynthetic and conducted bioinformatic analysis on sequencing nucleotide sequence. Analysis showed that: the size of fragments received from CYP716A52v2 clone was 1779 bp, with a 1445 bp-long open reading frame, an initiation codon at 93 bp, a stop codon at 1523 bp, and 481 encoded amino acids. The full-length CYP716A53v2 gene fragments was in the size of 1506 bp, with an initiation codon at 16 bp, a stop codon at 1423 bp, a 1410 bp-long open reading frame, and 470 encoded amino acids.2. Taking different tissues of quinquennial ginseng at different growth stages as test materials, this experiment measured the expression amount of gene CYP716A52v2 and CYP716A53v2. Results showed that: the expression amount of gene CYP716A52v2 gradually increased from leaf extension stage to root growth stage after fruiting and showed greatest difference between root growth stage after fruiting and leaf extension stage. The expression amount of gene CYP716A53v2 was relatively low at leaf extension stage and reached the highest level at root growth stage after fruiting. The expression amount of gene CYP716A53v2 in stems and leaves at leaf extension stage and red fruit stage was significantly higher than that in roots, while at root growth stage after fruiting the expression amount was significantly lower than that in roots. According to results, it was suspected that monobmer saponin Rg1 might have been synthesized in leaves and then transported to roots through stems. There was no big difference in the expression amount of gene CYP716A52v2 in all tissues at leaf extension stage. However, the expression amount in roots was significantly higher than that in other tissues from green fruit stage to root growth stage after fruiting. It was suspected that the reason might be that the modification of subsequent functional group of downstream synthetic pathways monobmer saponin Ro was synthesized in roots. This has laid the foundation for further study of ginsenoside synthesis.3. Taking individual plant root tissue of quinquennial ginseng as test materials, this experiment measured the amount of ginseng saponins and total saponins at different growth periods. The results showed that: there is synergistic growth trend between saponins, and monomer saponin Ro was obviously negatively correlated to total saponins. It might be related to the functions of downstream key enzymes in biosynthetic metabolic pathway of ginsenoside biosynthesis, which had laid the foundation for further study of the relationship between ecological factors and gene expression of key enzymes.4. This experiment conducted correlation analysis of ecological factors, gene expression amount, and saponin content. The results showed that: the expression amount of gene CYP716A52v2 was obviously positively related to average temperature and soil moisture content and monomer saponin Ro, was obviously negatively related to Rg1, Re and total saponins, and showed o obvious correlation to average rainfall, relative humidity, sunshine duration, and saponin content; as average temperature and soil moisture went higher, the expression amount of gene CYP716A52v2 went bigger as well, leading to a rise in Ro content and a decrease in the content of Rg1, Re and total saponins. The expression amount of gene CYP716A53v2 was obviously negatively related to average temperature and soil moisture content, and was obviously positively related to Rg1 and total saponins. As average temperature went higher, the expression amount of gene CYP716A53v2 went lower; and as soil moisture content went higher, the expression amount of gene CYP716A53v2, Rg1 and total saponins went higher as well. Soil moisture content and the monthly average temperature had relatively great impact on ginsenosides biosynthesis, while the average monthly rainfall, relative humidity, sunshine hours had relatively small impact; This showed that the expression of ecological factors and key enzyme genes had an impact on the ginsenosides synthesis.