苦荞糖基转移酶基因FtUGT143的克隆及表达分析

Cloning and Expression Analyses of C-glycosyltransferase Gene FtUGT143 in Fagopyrum tataricum

苦荞[Fagopyrum tataricum(L.)Gaertn]富含类黄酮C-糖苷,具有抗氧化、抗癌和消炎等多种保健作用。通过RT-PCR(reverse transcription-polymerase chain reaction)技术从苦荞中克隆得到了一个糖基转移酶基因,命名为FtUGT143,对其进行生物信息学、分子对接、基因表达、基因表达量与代谢物含量相关性等分析。结果表明,FtUGT143全长CDS序列为678 bp,编码226个氨基酸。密码子偏好分析结果显示,FtUGT143具有双子叶植物的密码子使用偏好性。多序列比对和进化树分析表明,FtUGT143是植物糖基转移酶基因家族中的C-糖基转移酶亚家族成员。分子对接结果表明,FtUGT143能与合成黄酮C-糖苷(牡荆素、异牡荆素、荭草素和异荭草素)的底物芹菜素和木犀草素相互作用。RT-qPCR结果显示,FtUGT143基因在苦荞的各个组织部位中均有表达,但在芽苗期的根、茎、叶中显著表达,且其在不同组织部位的表达量与4种黄酮C-糖苷积累量具有较好的相关性。研究结果表明FtUGT143是C-糖基转移酶,它可能参与苦荞中黄酮C-糖苷生物合成,对于揭示苦荞中黄酮C-糖苷的合成机制具有重要意义。

Tartary buckwheat[Fagopyrum tataricum(L.)Gaertn]is rich in flavonoid C-glycosides,and it has many health effects,such as anti-oxidation,anti-cancer and anti-inflammation.In this study,in order to explore the flavonoid C-glycosyltransferase gene in tartary buckwheat,a glycosyltransferase gene named FtUGT143 was cloned from tartary buckwheat by RT-PCR(reverse transcription-polymerase chain reaction),and its bioinformatics,molecular docking,gene expression,correlation between gene expression and metabolites content were also analyzed.The results showed that the full-length CDS sequence of FtUGT143 was 678 bp,encoding a protein of 226 amino acids.The codon preference analysis indicated that FtUGT143 had the codon usage preference of dicotyledons.Multiple sequence alignment and phylogenetic tree analysis suggested that FtUGT143 belonged to the carbon glycosyltransferase subfamily of plant glycosyltransferase gene family.The molecular docking analysis implied that FtUGT143 interacted with apigenin and luteolin,which were the substrates of flavonoid C-glycosides(vitexin,isovitexin,orientin and isoorientin).RT-qPCR results showed that FtUGT143 gene was expressed in all tissues of tartary buckwheat,but it was significantly expressed in the roots,stems and leaves at seedling stage,and its expression in different tissues had a good correlation with the accumulation of four flavonoid glycosides.The research results showed that FtUGT143 is a C-glycosyltransferase which may participate in the biosynthesis of flavonoid C-glycosides,revealing the important role of FtUGT143 in the synthesis mechanism of flavonoid C-glycosides in tartary buckwheat.