Effects of growth years on ginsenoside biosynthesis of wild ginseng and cultivated ginseng

Ginsenoside, as the main active substance in ginseng, has the function of treating various diseases. However, the ginsenosides content of cultivated ginseng is obviously affected by the growth years, but the molecular mechanism is not clear. In addition, there are significant differences in morphology and physiology between wild ginseng and cultivated ginseng, and the effect of growth years on ginsenoside synthesis not yet understood in wild ginseng.

Transcriptome sequencing on the roots, stems and leaves of cultivated ginseng and wild ginseng with different growth years was performed in this study, exploring the effect of growth years on gene expression in ginseng. The number of differentially expressed genes (DEGs) from comparison groups in cultivated ginseng was higher than that in wild ginseng. The result of weighted gene co-expression network analysis (WGCNA) showed that growth years significantly affected the gene expression of Mitogen-activated protein kinases (MAPK) signaling pathway and terpenoid backbone biosynthesis pathway in cultivated ginseng, but had no effects in wild ginseng. Furthermore, the growth years had significant effects on the genes related to ginsenoside synthesis in cultivated ginseng, and the effects were different in the roots, stems and leaves. However, it had little influence on the expression of genes related to ginsenoside synthesis in wild ginseng. Growth years might affect the expression of genes for ginsenoside synthesis by influencing the expression of these transcription factors (TFs), like my elob lastosis (MYB), NAM, ATAF1 and 2, and CUC2 (NAC), APETALA2/ethylene-responsive factor (AP2/ERF), basic helix-loop-helix (bHLH) and WRKY, etc., thereby affecting the content of ginsenosides.

This study complemented the gaps in the genetic information of wild ginseng in different growth periods and helped to clarify the potential mechanisms of the effect of growth years on the physiological state in wild ginseng and cultivated ginseng, which also provided a new insight into the mechanism of ginsenoside regulation.