Transcriptomic and metabolomic profiling of Polygonatum cyrtonema Hua across different growth years

Polygonatum cyrtonema Hua is a plant whose rhizome is famously used in traditional Chinese medicine. It has a wide range of pharmacological effects from the variety of active ingredients it contains, such as polysaccharides, flavonoid, and saponins. The increasing demand for P. cyrtonema is driven by growing public awareness of health. Artificial cultivation is the primary source of P. cyrtonema. Integrated transcriptomic and metabolomic analyses of biennial and triennial P. cyrtonema were used to investigate the impact of various growth years on the physiological mechanism of this plant. Using transcriptome analysis, 1721 differentially expressed genes (DEGs) were identified, comprising 1057 down-regulated and 664 up-regulated genes. The enrichment results of the Kyoto Encyclopedia of Genes and Genomes (KEGG) and other databases clarified the primary functions and enrichment sites of these DEGs, among which the phenylpropanoid biosynthetic pathway was the most crucial enrichment pathway. Additionally, 150 differential metabolites (DEMs) were derived from the metabolomics study, encompassing 78 down-regulated and 72 up-regulated metabolites. They underwent KEGG enrichment analysis in both POS and NEG modes. Through these different analyses, the common enrichment pathways-cofactors, glyoxylate and dicarboxylate metabolism, and carbohydrate metabolism were determined to be shared by them. Furthermore, several significant transcription factor families and pathways that are directly linked to the development of P. cyrtonema were discovered, including the bHLH, MYB, and NAC transcription factor families. Through in-depth study and analysis of these genes, their distinct roles in P. cyrtonema of various ages can be understood. This further suggests that growth years are one of the crucial factors affecting P. cyrtonema growth and development, active substance accumulation, and stress resistance.