粉花石榴二氢黄酮醇还原酶基因cDNA片段的分离及鉴定

Cloning and Identification of a DFR Gene Fragment from Pink Flower of Pomegranate

为了研究二氢黄酮醇还原酶(DFR)在石榴花色形成中的作用,根据GenBank中登录的相关物种DFR基因的保守序列设计简并引物,采用RT-PCR方法,从‘重瓣粉花’石榴花瓣总RNA中扩增出cDNA片段。测序结果表明,该cDNA片段长446bp,编码148个氨基酸,序列分析表明,该片段与蓝灰石竹、水蓼、苦荞麦、荞麦、甜樱桃、金荞麦、菠菜、马六甲葡萄、山葡萄、马蹄纹天竺葵、仙客来等物种的氨基酸同源性在78%～81%以上,存在一个底物结合特异性决定的氨基酸基序"TVNVQPVQRPVHDETSWSDLDFVWAT",说明已成功克隆到‘重瓣粉花’石榴DFR基因的cDNA片段,在GenBank中登录号为JN381544。

The aim was to study the role of dihydroflavonol 4-reductase formation. Degenerate PCR primers were designed based on （DFR） in pomegranate flower colors the conserved domain of some dihydroflavonol-4-reductase genes in GenBank. The aimed cDNA fragment was amplified from the total RNA isolated from pink flowers of pomegranate by RT-PCR. The sequencing results showed that the cDNA fragment was 446 bp encoding 148 amino acids. Sequence analysis indicated that the amino acid sequence shared 78%-81% homology to that of the corresponding region of dihydroflavonol 4-reductase gene of Diantbus qratianopolitanus, Polyqonum hydropiper, Faqopyrum tataricum, Faqopyrum esculentum, Prunus avium, Faqopyrum cymosum, Spinacia oleraeea, Syzyqium malaceense, Vitis vinifera, Pelarqonium zonale and Cyclamen graeeum. A substrate specificity motif （TVNVQPVQRPVHDETSWSDLDFVWAT） was observed in the deduced amino acid sequence. It confirmed that cDNA fragment cloned in this study was from DFR gene of pomegranate pink flower. The accession number of this gene in GenBank was JN381544.