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在被子植物中,2’-O-葡萄糖基转移酶能够影响花色色素分子的生物合成,在类黄酮上添加葡萄糖基配体,是形成黄色色素的关键酶.本研究采用RT-PCR技术首次从滇牡丹中克隆得到一个具完整开放阅读框的类黄酮-2’-O-葡萄糖基转移酶(Pd2’GT)基因,对其进行生物信息学分析和转录模式分析.研究发现该基因全长1 428 bp,可编码的蛋白氨基酸475个,该蛋白无信号肽和跨膜结构,是一种在细胞质基质中发挥功能的不稳定蛋白;核酸序列与葡萄(Vitis vinifera)糖基转移酶的核酸序列具78％的一致性,说明该基因可能编码一个新蛋白,其蛋白序列含糖基转移酶超家族结构域PSPG,其氨基酸残基序列为WAPQVAILSHRATGG FVSHCGWNSILESLWFGVPIAALPMYAEQQ,含典型的糖基转移酶识别区和UDP糖基配体绑定位点;该蛋白与苹果(Malus domestica,NP_001315903)、西洋梨(Pyrus communis,D3UAG1)、仙客来(Cyclamen persicum,BAF75895)和长春花(Catharanthus roseus,BAF75901)的2’GT聚为一类,该组的糖基受体均为查尔酮;转录模式分析表明:Pd2’GT基因在黄色花瓣中表达量最高,在花蕾期该基因的积累水平最高.本研究通过对滇牡丹转录组数据的分析,分离并克隆得到Pd2’GT基因,为通过基因工程手段培育具新性状的观赏牡丹提供研究依据.“,”In angiosperms, the 2’-O-glucosyltransferases (2’GT) can affect the biosynthesis of color pigment molecules, and adding glucosyl ligand to flavonoids is the key enzyme to form xanthophyl. The present study cloned a flavonoid 2’-O-glycosyltransferase (Pd2’GT) gene with complete ORF from Paeonia delavayi for the first time with the method of RT-PCR, and its bioinformatics and transcriptional pattern analysis were carried out. The results showed that the full length of Pd2’GT gene was 1 428 bp, encoding a protein of 475 amino acids. The protein had no signal peptide and transmembrane structure, which was an unstable protein functioning in cytoplasmic matrix.The identity between the nucleotide sequence of Pd2’GT and the glycosyltransferase gene of Vitis vinifera was78％, indicating that the Pd2’GT gene might encode a new protein. Its protein sequence contained glycosyltransferase superfamily domain PSPG, and its amino acid residue sequence was WAPQVAILSHRATGGFVSHCGWNSILESL WFG VPIAALPMYAEQQ, including the typical identifiable sites of glycosyltransferase and the binding sites ofUDP sugar moiety. This protein clustered together with the 2’GT of Malus domestica (NP_001315903), Pyrus communis (D3 UAG1), Cyclamen persicum (BAF75895), and Catharanthus roseus (BAF75901), and the sugar acceptor of this group was chalcone. The transcriptional pattern analysis clarified that the highest expression of Pd2’GT gene was in the yellow petals of P. delavyi, and the highest accumulation level of this gene was in the budding phase. In this study, the Pd2’GT gene was isolated and cloned through the analysis of the transcriptional data of Paeonia delavayi, which could provide research reference for the breeding of new ornamental peony by genetic engineering.