P. ginseng C.A. Meyer is a valuable Chinese herbal medicine that belongs to the Araliaceae family. Major obstacles to the continuous cropping of ginseng have severely restricted the sustainable development of the ginseng industry. The allelopathic effects of triterpenoid saponins play an important role in disorders related to continuous cropping; however, the mechanisms underlying the allelopathic autotoxicity of triterpenoid ginsenosides remain unknown. In this study, we performed mRNA and miRNA sequencing analyses to identify candidate genes and miRNAs that respond differentially to ginsenoside Ro stress in ginseng and their targets. The growth of the ginseng hairy roots was significantly inhibited under Ro stress (0.5 mg/L, Ro-0.5). The inhibition of root growth and injury to root-tip cells promoted the accumulation of the endogenous hormones indole-3-acetic acid and salicylic acid and inhibited the accumulation of abscisic acid and jasmonate acid. The accumulation of ginsenosides, except Rg3, was significantly inhibited under Ro-0.5 stress. An mRNA analysis of the Ro-0.5 and control groups showed that differentially expressed genes were mostly concentrated in the hormone signal transduction pathway. ARF7 and EFM were upregulated, whereas XTH23 and ZOX1 were downregulated. These genes represent important potential candidates for hormone-responsive continuous cropping diseases. In total, 74 differentially expressed miRNAs were identified based on the miRNA sequencing analysis, of which 22 were upregulated and 52 were downregulated. The target genes of ptc-miR156k_L + 1, mtr-miR156b-5p, gma-miR156a_R + 1, and mtr-miR156e all belonged to TRINITY_DN14567_c0_g4, which is a gene in the plant hormone signal transduction pathway. These four miRNAs were all negatively correlated with mRNA, indicating their likely involvement in the response of ginseng to continuous cropping disorders and the regulation of ginsenoside synthesis. Our findings provide useful insights for removing the barriers to continuous ginseng cropping and have important implications in the genetic engineering of plant stress responses.

中文翻译：

---

RNA测序揭示人参毛状根Ro胁迫下人参皂苷生物合成调控网络

人参CA Meyer 是属于五加科的一种名贵中草药。人参连作的主要障碍严重制约了人参产业的可持续发展。三萜皂苷的化感作用在连作相关病害中起重要作用；然而，三萜类人参皂苷的化感自毒作用的潜在机制仍然未知。在这项研究中，我们进行了 mRNA 和 miRNA 测序分析，以确定对人参及其靶标中人参皂苷 Ro 胁迫有不同反应的候选基因和 miRNA。人参毛状根的生长在Ro胁迫(0.5 mg/L, Ro-0.5)下受到显着抑制。根系生长的抑制和根尖细胞的损伤促进了内源激素吲哚-3-乙酸和水杨酸的积累，抑制了脱落酸和茉莉酸的积累。在 Ro-0.5 胁迫下，除 Rg3 外，人参皂苷的积累受到显着抑制。Ro-0.5 和对照组的 mRNA 分析表明，差异表达基因主要集中在激素信号转导通路中。ARF7 和 EFM 被上调，而 XTH23 和 ZOX1 被下调。这些基因代表了激素反应性连作病害的重要潜在候选基因。基于 miRNA 测序分析，总共鉴定出 74 个差异表达的 miRNA，其中 22 个上调，52 个下调。ptc-miR156k_L+1的靶基因，mtr-miR156b-5p、gma-miR156a_R+1和mtr-miR156e均属于TRINITY_DN14567_c0_g4，是植物激素信号转导通路中的一个基因。这4个miRNA均与mRNA呈负相关，表明它们可能参与了人参对连作病害的响应和人参皂苷合成的调控。我们的研究结果为消除连续种植人参的障碍提供了有用的见解，并对植物应激反应的基因工程具有重要意义。表明它们可能参与人参对连作病害的反应和人参皂苷合成的调节。我们的研究结果为消除连续种植人参的障碍提供了有用的见解，并对植物应激反应的基因工程具有重要意义。表明它们可能参与人参对连作病害的反应和人参皂苷合成的调节。我们的研究结果为消除连续种植人参的障碍提供了有用的见解，并对植物应激反应的基因工程具有重要意义。