Significance
Lonicera japonica Thunb. is a native species in the East Asian and used in traditional Chinese medicine. In order to reveal the regulatory mechanism of secondary metabolites during the flowering stages, transcriptomic, proteomic, and metabolomic analyses were performed. The integration analysis of omic-data illustrated that the metabolic changes over the flower developmental stages were mainly involved in sugar metabolism, lipopolysaccharide biosynthesis, carbon conversion, and secondary metabolism. Our results indicate that phenylpropanoids were accumulated attributing to the activated glycolysis process in the early stages, while the terpenoids biosynthetic pathways might be promoted by the transketolase-contained regulatory circuit in the late stages of L. japonica flower development.