Liu Rui-Cen, Li Li, Wang Chao-Fan, Wang Yi, Zhang Mei-Ping
School of Life Sciences, Jilin Agricultural University Changchun 130118, China.
School of Life Sciences, Jilin Agricultural University Changchun 130118, China Jilin Agricultural University,Research Center for Ginseng Genetic Resources Development and Utilization,Jilin Province Changchun 130118, China.
Zhongguo Zhong Yao Za Zhi. 2024 Jul;49(13):3473-3483. doi: 10.19540/j.cnki.cjcmm.20240413.101.
Panax ginseng is a perennial herb with the main active compounds of ginsenosides. Among the reported ginsenosides, ginsenoside Rg_1 not only has a wide range of medicinal functions and abundant content but also is one of the major ginsenoside for the quality evaluation of this herb in the Chinese Pharmacopoeia. The main biosynthesis pathway of ginsenoside Rg_1 in P. ginseng has been clarified, which lays a foundation for the comprehensive and in-depth analysis of the biosynthesis and regulatory mechanism of ginseno-side Rg_1. However, the biosynthesis of ginsenoside Rg_1 is associated with other complex processes involving a variety of regulatory genes and catalyzing enzyme genes, which remain to be studied comprehensively. With the transcriptome data of 344 root samples from 4-year-old P. ginseng plants and their corresponding ginsenoside Rg_1 content obtained in the previous study, this study screened out 217 differentially expressed genes(DEGs) with Rg_1 content changes by DEseq2 analysis in R language. Furthermore, the weighted gene co-expression network analysis(WGCNA) revealed 40 hub genes among the DEGs.Pearsoncorrelation analysis was further perforned to yield 20 candidate genes significantly correlated with ginsenoside Rg_1 content, and these genes were annotated to multiple metabolic processes including primary metabolism and secondary metabolism. Finally, the treatment of P. ginseng adventitious roots with methyl jasmonate indicated that 16 of these genes promoted the biosynthesis of ginsenoside Rg_1 in response to methyl jasmonate induction. Finally, one of the 16 genes was randomly selected to verify the function of the gene by genetic transformation and qRT-PCR and to confirm the rationality of the methodology of this study. The above results lay a foundation for studying the mechanism for regulation on the synthesis of ginsenoside Rg_1 and provide genetic resources for the industrial production of ginsenoside Rg_1.
人参是一种多年生草本植物，其主要活性成分是人参皂苷。在已报道的人参皂苷中，人参皂苷Rg_1不仅具有广泛的药用功能且含量丰富，还是《中国药典》中用于该药材质量评价的主要人参皂苷之一。人参中人参皂苷Rg_1的主要生物合成途径已得到阐明，这为全面深入分析人参皂苷Rg_1的生物合成及调控机制奠定了基础。然而，人参皂苷Rg_1的生物合成与其他复杂过程相关，涉及多种调控基因和催化酶基因，仍有待全面研究。利用前期研究获得的4年生人参植株344个根样本的转录组数据及其相应的人参皂苷Rg_1含量，本研究通过R语言中的DEseq2分析筛选出217个随Rg_1含量变化的差异表达基因（DEG）。此外，加权基因共表达网络分析（WGCNA）在这些DEG中揭示了40个核心基因。进一步进行Pearson相关性分析，得到20个与人参皂苷Rg_1含量显著相关的候选基因，这些基因被注释到包括初级代谢和次级代谢在内的多个代谢过程中。最后，用茉莉酸甲酯处理人参不定根表明，其中16个基因响应茉莉酸甲酯诱导促进了人参皂苷Rg_1的生物合成。最后，从这16个基因中随机选择一个，通过遗传转化和qRT-PCR验证该基因的功能，并确认本研究方法的合理性。上述结果为研究人参皂苷Rg_1合成的调控机制奠定了基础，并为人参皂苷Rg_1的工业化生产提供了遗传资源。
