Comparative Metabolome and Transcriptome Analysis Revealed the Accumulative Mechanism of Rubusoside in Chinese Sweet Tea.

Terpenoids are important secondary metabolites in . Rubusoside is a relatively specific diterpenoid bioactive component in the leaves of Chinese Sweet Tea (). However, the terpenoid anabolic pathway of and the molecular mechanism underlying the specific accumulation of rubusoside in remain unclear. Here, metabolomics and transcriptomics analyses were performed on differences in terpenoid metabolism levels between (sweet leaves) and (bitter leaves). Steviol glycosides and goshonosides primarily accumulated in and , respectively. Three pairs of highly homologous glycosyltransferase genes (, , and ) associated with rubusoside biosynthesis in the two species were identified. The three pairs of UGT proteins in both species could glycosylate steviol. Thus, the transcriptional regulation of in appears to play a pivotal role in rubusoside accumulation. Our findings provide insights into the differences in terpenoid metabolism between and and reveal the molecular mechanism of rubusoside accumulation in .