Anthocyanins,ubiquitous in the Compositae family,are regulated by MYB(v-myb avian myeloblastosis viral oncogene homolog),playing an important role in anthocyanin synthesis.In this study,we analyzed the regulation path...Anthocyanins,ubiquitous in the Compositae family,are regulated by MYB(v-myb avian myeloblastosis viral oncogene homolog),playing an important role in anthocyanin synthesis.In this study,we analyzed the regulation pathway in which the MYB protein of subgroup 6 promotes dihydroflavonol reductase(DFR)expression in Compositae,and validated this law in Saussurea medusa through yeast one-hybrid experiments.Our results showed that MYB and DFR underwent purification selection,DFR promoter analysis revealed the presence of MYB binding site(GAGTTGAATGG)and bHLH binding site(CANNTG)at the sense strand of 84–116 nucleotide residues from the start codon.These two motifs were separated by 9–10 nucleotide residues,as existed in the DFR promoters of many Compositae plants.Furthermore,the yeast one-hybrid experiment demonstrated that SmMYB1 can activate the promoter of SmDFR.Our results provide a reference for further functional study of DFR in Compositae.展开更多
基金This work was financially supported by the National Natural Science Foundation of China(31960222,31360095).
文摘Anthocyanins,ubiquitous in the Compositae family,are regulated by MYB(v-myb avian myeloblastosis viral oncogene homolog),playing an important role in anthocyanin synthesis.In this study,we analyzed the regulation pathway in which the MYB protein of subgroup 6 promotes dihydroflavonol reductase(DFR)expression in Compositae,and validated this law in Saussurea medusa through yeast one-hybrid experiments.Our results showed that MYB and DFR underwent purification selection,DFR promoter analysis revealed the presence of MYB binding site(GAGTTGAATGG)and bHLH binding site(CANNTG)at the sense strand of 84–116 nucleotide residues from the start codon.These two motifs were separated by 9–10 nucleotide residues,as existed in the DFR promoters of many Compositae plants.Furthermore,the yeast one-hybrid experiment demonstrated that SmMYB1 can activate the promoter of SmDFR.Our results provide a reference for further functional study of DFR in Compositae.
文摘二氢黄酮醇4-还原酶(dihydroflavonol 4-reduetase,DFR)是花色素苷合成途径中的一个关键酶。该研究利用RT-PCR和RACE技术从朵丽蝶兰‘满天红’深红色花瓣中克隆获得一个DFR基因,命名为DtpsDFR。该cDNA序列全长1 286 bp,编码378个氨基酸。氨基酸序列分析表明,DtpsDFR编码的蛋白与Bromheadia fi nlaysoniana、文心兰、大花蕙兰、石斛兰等兰科植物的DFR蛋白同源性均在76%以上,含有1个FR_SDR_e特征结构域,存在NADPH结合基序和底物特异性结合基序,属于NADB_Rossmann超家族;系统进化树显示,DtpsDFR与Bromheadia fi nlaysoniana的DFR蛋白亲缘关系最近。实时荧光定量PCR分析结果显示,DtpsDFR基因的表达量随着花的发育逐渐降低,凋谢期微量表达;在花瓣、萼片中的表达量高于唇瓣,在叶片和根中微量表达。
