Comprehensive analysis of flavonoids metabolism and transcription in different parts of Houttuynia cordata

Houttuynia cordata is a medicinal plant with diverse pharmacological activities, but the relationship between its flavonoid components and gene expression across different plant parts remains poorly understood. This study aims to explore these relationships using metabolomics and transcriptomics approaches.Differential metabolites were identified through a T-test and OPLS-DA (P <0.05,VIP>1).Transcriptomic data were analyzed for flavonoid biosynthesis-related genes using Fold Change≥2, FDR<0.01, and Benjamini-Hochberg correction.The roots were rich in flavonoids, while the stems exhibited higher hydroxyl group concentrations, and the leaves also contained significant flavonoid levels. A total of 22 differential metabolites (11 flavonoids) were identified between leaves and stems, 25 (14 flavonoids) between leaves and roots, and 32 (12 flavonoids) between stems and roots. KEGG analysis revealed that flavonoid, flavonol, and derivative biosynthesis were the primary metabolic pathways. Key enzymes, including flavanone 3-hydroxylase, flavonol synthase, and dihydroflavonol 4-reductase, were identified. Additionally, higher levels of glutathione enzymes in leaves and stems may facilitate flavonoid transport to roots.This study elucidates the relationship between metabolic components and gene expression in Houttuynia cordata, providing valuable insights for its comprehensive utilization in pharmacological applications.