mRNA翻译起始区二级结构改变对干扰素基因在大肠杆菌中翻译的影响  

The mutation of mRNA translation initiation region influences interferon gene translation

作　　者：张平武[1] 王易伦[1] 陆德如[1] 

机构地区：[1]第二军医大学生物技术和分子遗传研究所,上海200433

出　　处：《生物技术通讯》1998年第1期1-5,共5页Letters in Biotechnology

摘　　要：为研究mRNA翻译起始区结构与基因表达的关系,利用密码子的简并性,在不改变表达产物氨基酸序列的前提下定点突变α8干扰素及αA干扰素衍生物基因的5′端若干位点,使其与表达载体重组后转录形成的mRNA翻译起始区结构发生改变。SDS-PAGE及活性测定证实这些改变提高了外源基因的表达水平。RNA斑点印迹表明突变前后基因转录水平差别不大,表达水平的提高主要由于翻译效率的提高。mRNA翻译起始区二级结构预测提示其生成自由能(ΔG)的变化可能与表达水平的提高有关。In order to investigate the relationship between the structure of mRNA translation initiation region(TIR) and gene expression. We mutated multiple sites of 5' end of IFN-α8 and IFN-αA genes by site-directed mutagenesis without changing their amion acid sequences. SDS-PAGE showed the protein products of mutated genes increased greatly in recombinant clones, comparing with their native genes. RNA dot blot revealed the differences of their corresponding amount mRNA between native and mutated genes are negligible. These results imply that the elevated expressions are attributed mainly to increased translation level. The prediction of mRNA secondary structure suggests that the AG of TIR may have close relations to expression level.

关 键 词：翻译起始 二级结构 表达调控 干扰素 

分 类 号：Q75[生物学—分子生物学]