中文摘要：

在植物中,类黄酮3-O-葡萄糖基转移酶（F3GT）将不稳定的花色素转变为稳定的花色素苷,是花色素苷形成的关键酶。本研究采样RT-PCR技术从滇牡丹中成功克隆获得一个完整的F3GT基因（Pd F3GT1）,其含有1 371 bp的开放阅读框（ORF）,编码456个氨基酸。该基因推断的蛋白与葡萄（Vitis vinifera）3GT蛋白的相似性为64%;与已知功能的3GT基因进行系统进化分析,结果显示Pd3GT1与葡萄3GT聚类到同一个分支。氨基酸比对显示Pd3GT1蛋白序列还有糖基转移酶家族特有的PSPG-box结构域。半定量PCR结果显示：Pd3GT1在花蕾,花开时期的花瓣中大量表达,在叶和花芽中有微弱表达;在根和茎中没有表达。说明Pd3GT基因表达具有组织表达特异性。该研究将为研究滇牡丹花色素形成机理,以及对滇牡丹类黄酮糖基转移酶的功能鉴定和利用基因工程手段改良花卉品质提供理论依据。

英文摘要：

In plants, flavonoid 3-O-glucosyltransferas （F3GT）, which transforms unstable flower pigment into stable flower pigment, is the key enzyme for forming anthocyanin in flowers. In this study, we used RT-PCR technology to clone a complete F3GT gene from Paeonia delavayi. The gene sequence of Pd3GT1 consisted of 1 371 bp open reading frames （ORF） and encoded 456 amino acids. The deduced Pd3GT protein shared 64% similarity with that of Vitis vinifera 3GT. The system evolution analysis of 3GT gene with known function showed that Pd3GT1 and grape 3GT had the same branch. Amino acid alignment showed that Pd3GT1 protein sequence had PSPG-box structural domain which was peculiar to the family of glycosyl transferase. Semi-quantitative PCR results suggested that Pd3GT was strongly expressed in petal during pre-blossom and bloom stage, slightly expressed in leaf and bud, but wasn＇t expressed in root and stem, which meant that the expression of Pd3GT1 gene was of tissue-specificity. This study would provide theoretical basis for the study of mechanism of flower pigment biosynthesis in P delavayi, for functional identification offlavonoid 3-O-glucosyltransferase gene, and for improving flower quality by genetic engineering.