对昆虫的N-糖基化途径进行修饰改变是扩展昆虫蛋白表达系统应用范围的重要途径。本研究利用基于piggyBac转座子的家蚕Bombyx mori转基因技术表达昆虫所缺乏的哺乳类糖基化途径中的关键基因,构建了可以同时表达小鼠Mus musculus唾液酸合酶和小鼠CMP-唾液酸合成酶两个基因的piggyBac表达载体,选用家蚕肌动蛋白A3启动子控制基因的表达,并导入3×P3启动子控制下的增强绿色荧光蛋白EGFP作为分子标记。在得到的G1代转基因家蚕中对转入的基因进行了分子水平的鉴定和分析,为在家蚕这种模式昆虫中模拟哺乳类糖基化途径奠定了基础。
The N-glycosylation pathway in insects differs from the mammalian pathway,which limits insect-based expression system to produce mammalian glycoproteins with biomedical value. This study aims to produce transgenic Bombyx mori capable of processing glycoproteins as mammalian glycosylation pathways. Two key genes in mammalian N-glycosylation pathway,i.e.,mammalian sialic acid synthase and CMP-sialic acid synthetase genes,which were driven by B. mori actin3 promoter,were transformed into B. mori by piggyBac transgenic system. Enhanced green fluorescent protein(EGFP) which was driven by 3×P3 promoter was also introduced as a molecular selection marker. The expression of transformed genes was analyzed in G1 transgenic silkworms. The current study provides a solid evidence of simulating mammalian glycosylation pathways in the model insect B. mori.