Host: The Japanese Society of Plant Physiologists
Pages 0140
The large variety of over 7000 Flavonoid is derived from modification such as glycosylation, acylation and methylation. In Arabidopsis, the structures of 19 flavonoids suggest that at least 9 family-1 glycosyltransferase (UGT) and 3 acyltransferase are involved in flavonoid modification. However, UGTs are encoded by 107 genes in Arabidopsis. Their huge diversity makes it difficult to determine their physiological functions precisely.
To identify flavonoid UGT comprehensively, we utilized transcriptome coexpression analysis. A UGT gene, UGT5, was found to be correlated with flavonoid biosynthetic genes. UGT5 belongs to flavonoid 3-O-glycosyltransferase family. Compared with flavonoid profile in wild type, flavonol 3-O-pentoside derivatives were lacked in ugt5 mutant. UGT5 recombinant protein converted quercetin to quercetin 3-O-arabinoside. UGT5 recognized flavonol aglycones and UDP-arabinose but not flavonol glycosides and other UDP-sugars. These data show that UGT5 encodes flavonol 3-O-arabinosyltransferase.
