七彩红竹二氢黄酮醇4-还原酶基因IhDFR1的克隆及表达分析

Cloning and Expression Analysis of Dihydroflavonol 4-Reductase Gene IhDFRl from Indosasa hispida cv. 'Rainbow'

二氢黄酮醇4-还原酶(DFR)是植物花色素苷合成途径中的关键酶,在植物花色的形成过程中起重要作用。依据七彩红竹转录组数据设计特异引物,采用RT-PCR技术从七彩红竹中克隆获得了一个新的DFR基因cDNA全长,命名为IhDFR1(登录号为KF728205)。序列分析结果表明,IhDFR1基因cDNA全长945 bp,编码314个氨基酸。生物信息学预测显示,该基因编码的蛋白具有典型的DFR蛋白功能结构域,存在2个特异结合位点,属于非Asn/Asp型DFR酶,与禾本科植物中的DFR具有较高的相似性。对不同发育时期七彩红竹的IhDFR1基因进行时空表达的结果显示,只有在竹秆颜色呈现红紫色时,IhDFR1基因才有表达。以上结果初步显示IhDFR1蛋白可能作为一个重要的酶参与竹秆花色素苷的代谢调控,同时为进一步研究七彩红竹花色素苷产生的分子机理和综合开发利用奠定了基础。

Dihydroflavonol 4-reductase （DFR） is a key enzyme in the anthocyanins biosynthesis pathway, and plays a critical role in flower pigmentation. The gene-specific primers were designed according to the transcriptome sequencing data, and the full-length cDNA of a novel DFR gene was cloned from lndosasa hispida cv. ＇Rainbow＇ with the method of reverse transcription PCR. This novel gene was named as IhDFR1 （GenBank accession No. KF728205）. Sequence analysis indicated that lhDFR1 was 945 bp in length and encoded a protein with 314 amino acids. Bioinformatics analysis showed that lhDFR1 had the typical functional domains of DFR protein, containing two specific binding sites and belonging to the non-Asn/Asp DFR. The IhDFR1 was homologous with the DFRs from the gramineous plants. The temporal-spatial expression analysis based on different growth stages indicated that the IhDFR1 was expressed only in the reddish violet culms. The results above preliminarily suggested that the IhDFR1 might be an important enzyme governing anthocyanin metabolism, and lay a theoretical basis for further exploration of molecular mechanism of anthocyanins and for the comprehensive exploitation and utilization ofI. hispida cv. ＇Rainbow＇.