Multi-omics analysis reveals insights into the key genes involved in polysaccharide biosynthesis induced by red light intensity in Platostoma palustre

BACKGROUND : Platostoma palustre (Blume) A. J. Paton is a medicinal and edible plant in China, and polysaccharide is its main functional component, composed of various monosaccharides. This study aims to investigate the biosynthesis and regulatory mechanisms of polysaccharides in P. palustre. RESULTS: The results showed that increased red light intensity promoted the growth of P. palustre, and an increase in light intensity to a certain degree increased the concentrations of monosaccharides. Transcriptome sequencing showed that a total of 55 differentially expressed genes (DEGs) encoding enzymes involved in polysaccharide biosynthesis were identified as key functional genes. The pathways for polysaccharide biosynthesis in P. palustre were also reconstructed. Weighted gene coexpression network analysis (WGCNA) revealed 4 modules significantly correlated with 9 monosaccharides. Based on the high connectivities and expression levels, a total of 17 hub TFs, belonging to the B3_superfamily, AP2/ERF, bHLH, WRKY, and MYB families, were considered key regulatory genes. Additionally, protein interaction network analysis revealed that there were interactions between transcript_43348 (B3_superfamily) and transcript_20138 (Sucrose synthase, SuSy), between transcript_1530 (B3_superfamily) and transcript_35035 (bHLH), between transcript_1530 (B3_superfamily) and transcript_41067 (Sucrose non-fermenting-1-related protein kinase 2, SnRK2), and between transcript_52483 (AP2/ERF) and transcript_23314 (ARR-B). CONCLUSIONS: This study laid the foundation for elucidating the biosynthesis and regulatory mechanisms of polysaccharides in P. palustre.