霍乱毒素A、B亚基基因比例表达的精确调节  

Regulation mechanism of the proportional expression of cholera toxin subunits A and B genes

作　　者：曹诚[1] 李平[1] 李杰之[1] 石成华[1] 马清钧[1] 

机构地区：[1]军事医学科学院生物工程研究所,北京100850

出　　处：《军事医学科学院院刊》2000年第2期88-90,共3页Bulletin of the Academy of Military Medical Sciences

基　　金：北京市自然科学基金资助项目! (5 992 0 14)

摘　　要：研究霍乱毒素A亚基基因内部翻译起始序列的翻译起始效率与A亚基基因翻译起始效率的关系。方法 :将基因内翻译起始序列合成后克隆到上游含有起始密码和无起始密码的报告质粒中 ,研究表达水平的差异。结果 :在上游翻译起始区 (translationinitiationregion ,TIR)与报告基因间插入该序列 ,基因的表达水平提高 1倍 ;当上游的翻译起始密码由ATG突变为ATC时 ,内部翻译起始序列几乎失去翻译起始功能。结论 :TIR 1的翻译起始效率与上游起始序列的起始效率相同 ;且受上游翻译起始序列的精确调控。Objective: To investigate how the translation efficacy from the internal translation regulation element in cholera toxin subunit A gene is regulated by translation from the initiation of ctxA gene. Methods:One of the three internal translation initiation region(TIR) was chemically synthesized and cloned into the report plasmid, and the expression of the report gene was studied. Results:When the TIR sequence was inserted between the TIR of upstream gene and the report gene, the expression level of the report gene was doubled;When the ATG of the upstream gene was changed to ATC, no translation occurred from the internal TIR. Conclusion: The translation initiation efficacy from TIR 1 is same as that from the upstream gene and was controlled by the TIR from the upstream region. [

关 键 词：霍乱毒素 热不稳定毒素 操纵子 翻译调控 

分 类 号：R378[医药卫生—病原生物学]