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目的：以具有广泛助溶活性的小泛素相关修饰蛋白（ small ubiquitin－related modifier，SUMO）为辅助蛋白，利用翻译偶联，构建一种新型非融合可溶原核表达载体，实现广谱抗病毒蛋白RA在大肠杆菌中的非融合可溶表达。方法以PCR方法从酵母基因组中克隆SUMO蛋白基因smt3并进行定点突变，去除其中的EcoRⅠ酶切位点，获得同义突变体mSUMO。通过翻译偶联Linker序列的设计、合成，构建以mSUMO蛋白为辅助蛋白的翻译偶联表达载体pTIG－mSUMO。 PCR扩增获得带有相应酶切位点的广谱抗病毒蛋白 RA 的基因，将其克隆至 pTIG－mSUMO中，获得表达载体pTIG－mSUMO／RA，实现RA在大肠杆菌中的非融合可溶性表达。结果 IPTG诱导蛋白表达以后，SDS－PAGE和Western印迹检测证实，目的蛋白RA的表达量明显增加，且可溶比例约占50％。结论以优化后的SUMO为辅助蛋白，成功构建了一种非融合的可溶原核表达载体pTIG－mSUMO，实现了RA蛋白在大肠杆菌中的高效非融合可溶表达，既提高了表达水平，也提高了可溶性。 pTIG－mSUMO作为一种可溶的非融合表达载体，在实现外源蛋白的高效可溶表达方面，很可能具有一定的普遍性。“,”Objective To design and construct a new non-fusion soluble expression vector pTIG-mSUMO(small ubiq-uitin-related modifier) using the widely used solubility promoting protein SUMO and based on the translational coupling phenomenon in order to enable the non-fusion soluble expression of the broad-spectrum antiviral protein RA in Escherichia coli by pTIG-mSUMO.Methods The smt3 gene coding for SUMO protein was cloned from yeast genome DNA by PCR. After directed-site silent mutation to eliminate the EcoRⅠsite, the mutant mSUMO was inserted into pET-22b to obtain the translational coupling expression vector pTIG-mSUMO.The RA was subject to PCR amplification and cloned into the pTIG-mSUMO to obtain the expression plasmid pTIG-mSUMO/RA which was supposed to direct the soluble expression of RA by the translational coupling with mSUMO.Results A translational coupling expression vector pTIG-mSUMO which could di-rect/drive the SUMO and heterogonous protein non-fusion expression simultaneously was designed and constructed.The Western blotting result indicated that pTIG-mSUMO could direct the high-level expression of RA, around 40%of which was soluble.Conclusion A translational coupling expression vector pTIG-mSUMO is obtained.After coupling with SUMO, RA is highly expressed in E.coli and both the expression level and solubility are greatly improved.pTIG-mSUMO might contrib-ute to soluble expression of other proteins.