Chu Y X, Chen H R, Wu A Z, Cai R, Pan J S
Institute for Agri-Food Standards and Testing Technology, Shanghai Academy of Agricultural Sciences, Shanghai, China.
School of Agriculture and Biology, Shanghai Jiaotong University, Shanghai, China.
Genet Mol Res. 2015 May 12;14(2):5010-21. doi: 10.4238/2015.May.12.4.
Dihydroflavonol 4-reductase (DFR) genes from Rosa chinensis (Asn type) and Calibrachoa hybrida (Asp type), driven by a CaMV 35S promoter, were integrated into the petunia (Petunia hybrida) cultivar 9702. Exogenous DFR gene expression characteristics were similar to flower-color changes, and effects on anthocyanin concentration were observed in both types of DFR gene transformants. Expression analysis showed that exogenous DFR genes were expressed in all of the tissues, but the expression levels were significantly different. However, both of them exhibited a high expression level in petals that were starting to open. The introgression of DFR genes may significantly change DFR enzyme activity. Anthocyanin ultra-performance liquid chromatography results showed that anthocyanin concentrations changed according to DFR enzyme activity. Therefore, the change in flower color was probably the result of a DFR enzyme change. Pelargonidin 3-O-glucoside was found in two different transgenic petunias, indicating that both CaDFR and RoDFR could catalyze dihydrokaempferol. Our results also suggest that transgenic petunias with DFR gene of Asp type could biosynthesize pelargonidin 3-O-glucoside.
由花椰菜花叶病毒35S启动子驱动的来自中国玫瑰（天冬酰胺型）和小花矮牵牛（天冬氨酸型）的二氢黄酮醇4-还原酶（DFR）基因被整合到矮牵牛（矮牵牛杂交种）品种9702中。外源DFR基因的表达特征与花色变化相似，并且在两种类型的DFR基因转化体中均观察到对花青素浓度的影响。表达分析表明，外源DFR基因在所有组织中均有表达，但表达水平存在显著差异。然而，它们在开始开放的花瓣中均表现出高表达水平。DFR基因的渗入可能会显著改变DFR酶活性。花青素超高效液相色谱结果表明，花青素浓度随DFR酶活性而变化。因此，花色变化可能是DFR酶变化的结果。在两种不同的转基因矮牵牛中均发现了天竺葵素3-O-葡萄糖苷，表明CaDFR和RoDFR都可以催化二氢山奈酚。我们的结果还表明，具有天冬氨酸型DFR基因的转基因矮牵牛可以生物合成天竺葵素3-O-葡萄糖苷。
