Multi‐omics identification of a key glycosyl hydrolase gene FtGH1 involved in rutin hydrolysis in Tartary buckwheat (Fagopyrum tataricum)

Abstract

SummaryRutin, a flavonoid rich in buckwheat, is important for human health and plant resistance to external stresses. The hydrolysis of rutin to quercetin underlies the bitter taste of Tartary buckwheat. In order to identify rutin hydrolysis genes, a 200 genotypes mini‐core Tartary buckwheat germplasm resource was re‐sequenced with 30‐fold coverage depth. By combining the content of the intermediate metabolites of rutin metabolism with genome resequencing data, metabolite genome‐wide association analyses (GWAS) eventually identified a glycosyl hydrolase gene FtGH1, which could hydrolyse rutin to quercetin. This function was validated both in Tartary buckwheat overexpression hairy roots and in vitro enzyme activity assays. Mutation of the two key active sites, which were determined by molecular docking and experimentally verified via overexpression in hairy roots and transient expression in tobacco leaves, exhibited abnormal subcellular localization, suggesting functional changes. Sequence analysis revealed that mutation of the FtGH1 promoter in accessions of two haplotypes might be necessary for enzymatic activity. Co‐expression analysis and GWAS revealed that FtbHLH165 not only repressed FtGH1 expression, but also increased seed length. This work reveals a potential mechanism behind rutin metabolism, which should provide both theoretical support in the study of flavonoid metabolism and in the molecular breeding of Tartary buckwheat.

Genome-wide identification of ZmMYC2 binding sites and target genes in maize

“…In addition, many glycoside hydrolase encoding genes were also regulated directly by ZmMYC2, which might be involved in specialized metabolism. In tartary buckwheat, FtGH1 (β-glucosidase) converted rutin to quercetin, playing the key role in rutin hydrolysis [ 94 ]. Glutathione S-transferase is a super family with the main functions of detoxification and specialized metabolism.…”

Genomic insight into the origin, domestication, dispersal, diversification and human selection of Tartary buckwheat

“…Among them, 474 accessions were collected from China, and 93 accessions were collected from the other 16 countries (Additional file 1 : Table S1). 489 accessions were re-sequenced in previous research [ 8 , 61 ], and 78 accessions were newly re-sequenced in this study. Genomic DNA was extracted using cetyltrimethylammonium bromide (CTAB) as previously described [ 8 ].…”