猪生长激素基因在昆虫细胞中的分泌表达

将PCR将增得到pGH基因插入到带有polh启动子和gp67强信号肽序列的杆状病毒转移载体pAcGP67-A中，构建重组质粒pGP67pGH，并与线性化致死缺失型苜蓿丫纹夜蛾核多角体病毒（AcMNPV-OCC)基因组DNA共转染Sf9细胞，构建出重组病毒AcMNPV-pGP67-pGH-OC^-。感染重组病毒的Hi5细胞的表达产物的SDS-PAGE和Western blot结果表明，细胞可溶蛋白和培养液上清中均有一条分子量约为22kDa的猪生长激素特异性反应带，且培养液上清中的目的蛋白分子量比天然pGH略大一些，薄层扫描仪扫描估测可知，重组pGH分别占细胞可溶蛋白的8．98％和培养液上清总蛋白的3.61%。将表达96h的培养液上清浓缩液进行N－糖基化分析，结果显示重组pGH无N－糖基化加工修饰。

Secretion Expression of Porcine Growth Hormone Gene in Insect Cells

The porcine growth hormone gene was obtained by PCR and inserted into the baculovirus expression vector of pAcGP67-A which contains polh promoter and gp67 signal sequence.The recombinant plasmid of pGP67-pGH was cotransfected Hi5 cells with the linearized parental virus Ac MNPV-OCC - DNA to produce the recombinant virus Ac MNPV-pGP67-pGH-OCC -.SDS-PAGE and Western blot analysis showed that pGH gene products were observed,those in the supernatant with a little larger molecular weight size than the natural pGH's. The expressed pGH accumulated up to about 3.61% of the supernatant proteins and 8.98% of the soluble cellular proteins respectively as estimated by CS-930 scanning of the SDS-PAGE.The N-glycosylation analysis showed the recombinant pGH had no N-glycosylation.