利用家蚕核型多角体病毒多角体蛋白序列提高人表皮细胞生长因子表达水平

Enhancing the expression level of human epidermal growth factor using the polyhedrin protein sequence of BmNPV

人表皮细胞生长因子(human epidermal growth factor,hEGF)可用于治疗外科创伤(烧伤、烫伤)、修复组织、滋润皮肤、美容养颜等,但目前存在表达量低、价格昂贵等缺点。为了提高hEGF的表达水平、降低生产成本,本研究使用家蚕杆状病毒表达载体系统,利用多角体蛋白超高水平表达的现象,使用部分多角体蛋白序列与密码子优化后的hEGF融合进行表达,并将多个hEGF基因进行了串联表达,构建了N端融合不同多角体蛋白部分序列的多种融合表达载体。结果表明,通过上述策略,hEGF的蛋白表达水平显著提高,其中融合多角体N末端蛋白25个或者35个氨基酸编码序列、3个密码子优化后hEGF串联的表达载体表达水平最高。

Human epidermal growth factor(hEGF)can be applied in the treatment of surgical trauma(burns,scalds),tissue repair,skin moisturizing,beauty,skincare,etc.However,the low expression and high cost limit the application of hEGF.In order to improve the expression level of hEGF and reduce the production cost,considering the high expression of polyhedrin,this study fused a partial sequence of polyhedrin with hEGF and expressed the fused sequence by using a silkworm baculovirus expression vector system.In view of the small molecular weight of hEGF,we connected hEGF genes in series and optimized the codons to construct multiple fusion expression vectors by fusing different partial sequences of polyhedrin at the N-terminus.The results showed that through the above strategy,the protein expression level of hEGF was significantly increased.The expression vector containing three concatenated hEGF genes with optimized codons and fused with the sequence encoding 25 or 35 residues at the N-terminus of polyhedrin showed the highest expression level.