慢性HCV感染者中分离的不同长度3'UTR-PolyU/UC段对IRES介导的翻译及NS5B合成RNA影响

• 作 者: 王华 叶荣 兰水云 袁正宏
• 机 构: 复旦大学上海医学院医学分子病毒学重点实验室,复旦大学上海医学院医学分子病毒学重点实验室,复旦大学上海医学院医学分子病毒学重点实验室,复旦大学上海医学院医学分子病毒学重点实验室 200032上海,200
• 出 处: 中华微生物学和免疫学杂志
• 发表日期: 2004年05期
• 关键词: 丙型肝炎病毒 3'非编码区 PolyU/UC区 NS5B聚合酶

目的　研究丙型肝炎病毒 3′非编码区 (3′UTR)及不同长度PolyU UC段对内在核糖体进入位点 (IRES)介导翻译的影响以及对NS5B聚合酶合成RNA的影响。方法　通过构建含有HCVIRES、荧光素酶 (fireflyluciferase)报道基因和内含不同长度PolyU UC区的 3′UTR序列的系列重组质粒 ,采用体外翻译和细胞转染等方法检测报道基因表达的水平。结果　体外翻译实验和细胞转染实验显示 3′UTR对IRES介导的翻译具有增强作用 ,在体外翻译体系中这种增强作用与PolyU UC区的长度相关 ,而在细胞中则与PolyU UC区的长度无明显相关性 ;3′UTR对共转染的重组NS5B质粒的复制活性具有抑制作用 ,这种抑制作用也与PolyU UC区长度不成正比。结论　HCV 3′UTR与蛋白翻译及RNA合成有关 ,在细胞中并不与PolyU UC区的长度相关。

Objective To investigate the effects of 3 ’untranslated region (3’UTR) and different lengths of PolyU UC on the internal ribosomal entry site (IRES) -mediated translation and the effect of NS5B polymerase on RNA synthesis. Methods A series of recombinant plasmids containing HCVIRES, fireflyluciferase reporter gene and 3’UTR sequences containing different length PolyU UC region were constructed. The expression of reporter gene was detected by in vitro translation and cell transfection. Results In vitro translation experiments and cell transfection experiments showed that 3’UTR had an enhancement on IRES-mediated translation. In vitro translation system, this enhancement was related to the length of PolyU UC region but not to PolyU UC region 3’UTR had an inhibitory effect on the replication activity of the co-transfected recombinant NS5B plasmid and this inhibition was also not proportional to the length of the PolyU UC region. Conclusion HCV 3’UTR is related to protein translation and RNA synthesis, but not to length of PolyU UC in cells.