人神经病靶标酯酶RNAi表达载体的构建及其对哺乳动物细胞中NTE表达的抑制

目的构建人神经病靶标酯酶（NTE）双链RNA的稳定表达载体。方法用SpeI和XhoI将pSUPER质粒中的H1 RNA聚合酶Ⅲ启动子及多克隆位点部分切下替换pcDNA3．1（＋）载体中的巨嗜细胞病毒（CMV）启动子及其多克隆位点，构建了适合在哺乳动物细胞中表达具有干涉作用的小RNA的载体pSUPER／neo，进而将针对NTE表达的双链DNA插入到Bgl Ⅱ和Hind Ⅲ酶切的载体pSUPER／neo中构建NTE的双链RNA表达载体pSUPER/neo-NTE，后者被转染到COS7和SH-SYSY细胞中，采用蛋白质杂交和酶活力测定的方法，检测其表达效率并验证载体构建的TF确性。结果构建了适合在真核细胞用抗生素筛选的NTE双链RNA表达载体pSUPER／neo-NTE。蛋白质杂交检测显示，转染细胞能有效抑制外源性NTE的表达；酶活力测定则显示其能有效地抑制内源性NTE的表达．结论采用启动子替换的策略，成功构建了NTE双链RNA的表达载体并在哺乳动物细胞内有效抑制NTE的表达。

Construction of RNA interference expression vectors of human neuropathy target esterase and its inhibition for expression of NTE in mammalian cells

OBJECTIVE: To construct the RNA interference expression vector for expression of human neuropathy target esterase (NTE) gene in mammalian cells. METHODS: Spe I and Xho I-digested insert from pSUPER, which comprised H1 RNA polymerase III promoter and the multiple cloning sites, were cloned into the compatible in the pcDNA3.1 (+) to generate pSUPER/neo that could express small interfering RNA in mammalian cells. The annealed oligos targeting the expression of NTE were ligated into pSUPER/neo vector digested with Bgl II and Hind III to generate pSUPER/neo-NTE, which was transfected into COS7 and SH-SY5Y cells. The inhibitory effect of the expression of NTE was detected by western blot analysis and the enzyme activity assay. RESULTS: pSUPER/neo-NTE could stably express double-stranded RNA of NTE. The expression of pSUPER/neo-NTE in COS7 and SH-SY5Y cells could efficiently inhibit the activity of NTE in the mammalian cells. CONCLUSION: Stable eukaryotic expression vector of double-stranded RNA of NTE, pSUPER/neo-NTE, has been constructed successfully with promoter substitution strategy.