PDF(Pubmed)
Abstract：
Ginseng, an important medicinal plant, is characterized by its main active component, ginsenosides. Among more than 40 ginsenosides, Rg1 is one of the ginsenosides used for measuring the quality of ginseng. Therefore, the identification and characterization of genes for Rg1 biosynthesis are important to elucidate the molecular basis of Rg1 biosynthesis. In this study, we utilized 39,327 SNPs and the corresponding Rg1 content from 344 core ginseng cultivars from Jilin Province. We conducted a genome-wide association study (GWAS) combining weighted gene co-expression network analysis (WGCNA), SNP-Rg1 content association analysis, and gene co-expression network analysis; three candidate Rg1 genes (PgRg1-1, PgRg1-2, and PgRg1-3) and one crucial candidate gene (PgRg1-3) were identified. Functional validation of PgRg1-3 was performed using methyl jasmonate (MeJA) regulation and RNAi, confirming that this gene regulates Rg1 biosynthesis. The spatial-temporal expression patterns of the PgRg1-3 gene and known key enzyme genes involved in ginsenoside biosynthesis differ. Furthermore, variations in their networks have a significant impact on Rg1 biosynthesis. This study established an accurate and efficient method for identifying candidate genes, cloned a novel gene controlling Rg1 biosynthesis, and identified 73 SNPs significantly associated with Rg1 content. This provides genetic resources and effective tools for further exploring the molecular mechanisms of Rg1 biosynthesis and molecular breeding.
摘要：
人参,一种重要的药用植物，以其主要活性成分为特征，人参皂苷。在40多种人参皂苷中，Rg1是用于测定人参质量的人参皂苷之一。因此,Rg1生物合成基因的鉴定和表征对于阐明Rg1生物合成的分子基础很重要。在这项研究中,我们利用了吉林省344个核心人参品种的39,327个SNP和相应的Rg1含量。我们进行了全基因组关联研究（GWAS）结合加权基因共表达网络分析（WGCNA），SNP-Rg1含量关联分析，和基因共表达网络分析；鉴定了三个候选Rg1基因（PgRg1-1，PgRg1-2和PgRg1-3）和一个关键候选基因（PgRg1-3）。使用茉莉酸甲酯（MeJA）调节和RNAi进行PgRg1-3的功能验证，证实该基因调节Rg1生物合成。PgRg1-3基因和已知参与人参皂苷生物合成的关键酶基因的时空表达模式不同。此外，它们的网络变化对Rg1的生物合成有显著影响。本研究建立了一种准确、高效的候选基因鉴定方法,克隆了一个控制Rg1生物合成的新基因，并鉴定出73个与Rg1含量显著相关的SNP。这为进一步探索Rg1生物合成的分子机制和分子育种提供了遗传资源和有效工具。
