Glycosylation of Secondary Metabolites: A Multifunctional UDP-Glycosyltransferase, CsUGT74Y1, Promotes the Growth of Plants

Abstract

<i>Camellia sinensis</i> contains numerous glycosylated secondary metabolites that provide various benefits to plants and humans. However, the genes that catalyze the glycosylation of multitype metabolites in tea plants remain unclear. Here, 180 uridine diphosphate-dependent glycosyltransferases that may be involved in the biosynthesis of glycosylated secondary metabolites were identified from the National Center for Biotechnology Information public databases. Subsequently, <i>CsUGT</i>74<i>Y</i>1 was screened through phylogenetic analysis and gene expression profiling. Compositional and induced expression analyses revealed that <i>CsUGT</i>74<i>Y</i>1 was highly expressed in tea tender shoots and was induced under biotic and abiotic stress conditions. <i>In vitro</i> enzymatic assays revealed that rCsUGT74Y1 encoded a multifunctional UGT that catalyzed the glycosylation of flavonoids, phenolic acids, lignins, and auxins. Furthermore, <i>CsUGT</i>74<i>Y</i>1-overexpressing <i>Arabidopsis thaliana</i> exhibited enhanced growth and accumulation of flavonol and auxin glucosides. Our findings provide insights into identifying specific UGTs and demonstrate that <i>CsUGT</i>74<i>Y</i>1 is a multifunctional UGT that promotes plant development.