Illuminating the biosynthesis pathway genes involved in bioactive specific monoterpene glycosides in Paeonia veitchii Lynch by a combination of sequencing platforms.

BACKGROUND: Paeonia veitchii Lynch, a well-known herb from the Qinghai-Tibet Plateau south of the Himalayas, can synthesize specific monoterpene glycosides (PMGs) with multiple pharmacological activities, and its rhizome has become an indispensable ingredient in many clinical drugs. However, little is known about the molecular background of P. veitchii, especially the genes involved in the biosynthetic pathway of PMGs. RESULTS: A corrective full-length transcriptome with 30,827 unigenes was generated by combining next-generation sequencing (NGS) and single-molecule real-time sequencing (SMRT) of six tissues (leaf, stem, petal, ovary, phloem and xylem). The enzymes terpene synthase (TPS), cytochrome P450 (CYP), UDP-glycosyltransferase (UGT), and BAHD acyltransferase, which participate in the biosynthesis of PMGs, were systematically characterized, and their functions related to PMG biosynthesis were analysed. With further insight into TPSs, CYPs, UGTs and BAHDs involved in PMG biosynthesis, the weighted gene coexpression network analysis (WGCNA) method was used to identify the relationships between these genes and PMGs. Finally, 8 TPSs, 22 CYPs, 7 UGTs, and 2 BAHD genes were obtained, and these putative genes were very likely to be involved in the biosynthesis of PMGs. In addition, the expression patterns of the putative genes and the accumulation of PMGs in tissues suggested that all tissues are capable of biosynthesizing PMGs and that aerial plant parts could also be used to extract PMGs. CONCLUSION: We generated a large-scale transcriptome database across the major tissues in P. veitchii, providing valuable support for further research investigating P. veitchii and understanding the genetic information of plants from the Qinghai-Tibet Plateau. TPSs, CYPs, UGTs and BAHDs further contribute to a better understanding of the biology and complexity of PMGs in P. veitchii. Our study will help reveal the mechanisms underlying the biosynthesis pathway of these specific monoterpene glycosides and aid in the comprehensive utilization of this multifunctional plant.

[Research progress on chemical constituents,pharmacological activities,and quality control of Patrinia villosa].

Patrinia villosa, regarding its functions in clearing heat and detoxification and eliminating carbuncles and pus, is widely used as a traditional medicinal herb that contains rich nutrition and substances such as various amino acids, vitamins, and soluble su-gar, and it is also an edible wild herb in Chinese folk tradition for 2 000 years. In 1973, Japanese scholars firstly separated three iridoids from Japanese P. villosa, and by 2021, chemical components such as flavonoids, iridoids, organic acids, triterpenoids, phenylpropanoids, and steroids have been found, which have multiple pharmacological effects, including antioxidant, antitumor, anti-diarrhea, antibacterial, sedative, and liver protection capabilities. Studies indicate that flavonoids, saponins, phenylpropanoids, and triterpenoids in P. villosa are vital substances for its pharmacological activities. However, the quality of this medicinal material cannot be controlled due to the unclear records in ancient books in the past dynasties and different drug use habits in different places, and thus its circulation is chaotic. At present, researchers have used flavonoids, organic acids, phenylpropanoids, triterpenoid saponins, and other compounds to conduct studies in this regard. Therefore, on the basis of the existing literature resources, we comprehensively summarize the chemical constituents, pharmacological activities, and quality control of P. villosa to further provide a reference for the safety and effectiveness of clinical drug use and lay a foundation for the follow-up experimental research.