生长激素信号肽可诱导重组蛋白外分泌表达

重组蛋白质的表达是生物医药开发、基因功能和作用机理研究中关键技术环节.虽然细菌表达体系由于表达量大、经济等而被广泛采用,但由于其不能提供许多蛋白质必需的翻译后修饰如糖基化等,所表达的蛋白又多以不可溶包涵体形式存在,变性复性过程复杂,产率低,因此真核细胞表达体系如CHO、COS等成为活性要求高的蛋白质表达的首选1].

Secretion of Recombinant Proteins in Mammalian Cells Directed by Growth Hormone Signal Peptide

Signal peptide capable of efficiently directing many protein secretion in mammalian cells is one of the key elements in recombinant protein production,gene therapy and the development of DNA vaccines.In order to explore the possibility of rat growth hormone signal peptide as such an element,a new vector based on the mammalian expression vector pcDNA3 was constructed by employing rat growth hormone(rGH) signal peptide as leading sequence,followed by multiple cloning sites,the myc epitope-tag and 6×his purification tag in the expression cassette.The vector was validated by successfully expressing and secretion of chick MMP-2 C-terminal PEX domain,a potential angiogenesis inhibitor,and tandem peptide repeats of myc epitope-tag in COS-7 cells.These results suggest that rat growth hormone signal peptide is effective in the mediation of recombinant protein expression and secretion,and this vector provides a new tool for universal cloning and secretion of exogenous proteins in mammalian cells.