【摘要】 为了提高转基因动物乳腺特异性表达水平,构建了两种不同启动子的乳腺特异性表达载体,以比较其乳腺特异性表达效果。应用山羊β-酪蛋白或牛αs1-酪蛋白调控序列、鸡β-球蛋白隔离元件、巨细胞病毒(CMV)基因表达调控元件构建了乳腺特异性表达复合启动/增强子(Pcmv),以单一的酪蛋白启动子作为对照,与人乳铁蛋白cDNA组成乳腺特异性表达载体,并制备了转基因小鼠。经ELISA检测,复合启动/增强子构件指导人乳铁蛋白cDNA在原代转基因小鼠乳腺中重组人乳铁蛋白(rhLF)表达水平(2.0~8.1 g.L-1)明显高于单一酪蛋白启动子构件(0~12 mg.L-1),而在所有转基因小鼠的血清和唾液中未检测到rhLF。结果提示:酪蛋白-Pcmv复合启动/增强子不仅可提高转基因小鼠乳腺特异性表达水平,而且具有良好的乳腺表达特异性。更多还原

【Abstract】 To increase the expression levels for heterogenous protein in the mammary gland of transgenic animals,four vectors with different promoters were constructed.The chimeric vectors were constructed by using sequences of goat casein,bovine αs1-casein,chicken β-globin insulators,cytomegalovirus promoter/enhancer(Pcmv),and SV40 polyadenylation for producing a set of casein-Pcmv chimeric promoters/enhancers.The vectors of mono-promoters of casein elements were also constructed as the control.All constructs were used to generate transgenic mice.Using ELISA assays,results showed that the rhLF expression was significantly increased in the transgenic mice with chimeric promoters.The expression level was 2.0-8.1 g·L-1 in the milk using chimeric promoter.In contrast,only 0-12 mg·L-1 was found in the milk using mono-casein promoter.In addition,rhLF was not detected in serum and saliva.The result suggested that the constructs with chimeric promoter could increase the expression of heterogenous protein in the mammary gland of transgenic animals with high specificity.更多还原