Since the successful creation of DJ-526, a resveratrol-enriched rice cultivar, research has focused on resveratrol production because of its great potential in pharmaceutical applications. However, the utilization of resveratrol in DJ-526 is limited by glycosylation, which converts resveratrol to its glucoside (piceid), in a process driven by glycosyltransferase. The verification of resveratrol-dependent glycosyltransferase activity is an essential strategy for improving resveratrol production in DJ-526 rice. In this study, 27 candidate glycosyltransferases were evaluated in germinated seeds. Among the candidates, only R12 exhibited upregulation related to increased resveratrol and piceid content during seed germination, whereas various effects on the activity of glycosyltransferase were observed by the presence of a bio-elicitor. Yeast extract tended to enhance glycosyltransferase activity by seven candidates, and a specific peak for an unknown compound production was identified. Conversely, chitosan acted as a glycosyltransferase inhibitor. Our results suggested that R12 and R19 are the most relevant candidate resveratrol-dependent glycosyltransferases in DJ-526 seeds during germination and elicitation. Future research should assess the possibility of silencing these candidate genes in an effort to improve resveratrol levels in DJ-526 rice.
Keywords: GM rice; Glycosyltransferase; gene expression; resveratrol; seed germination.