在大肠杆菌trpR基因的表达中,通过绕过其编码序列的片段来发生移
1Department of Molecular Biology, Hebrew University, Hadassah Medical School, Jerusalem, Israel.
Cell
|January 15, 1993
概括
大肠杆菌中的一种新型基因表达机制涉及翻译绕过,在蛋白质合成过程中跳过特定的mRNA段. 这一对于trpR基因表达至关重要的过程,表明了转化内核的潜在存在.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 微生物学 微生物学
背景情况:
- 大肠杆菌 (E. coli) 的trpR基因编码了trp抑制蛋白.
- 之前的研究发现了trpR基因表达过程中的+1框架转移事件.
研究的目的:
- 阐明大肠杆菌trpR基因表达中的+1框架转移事件的机制.
- 研究mRNA序列和结构在翻译框架转移中的作用.
主要方法:
- 对trpR+1-lacZ mRNA结构的分析.
- 调查翻译绕过的要求.
- 研究特定的mRNA序列和上游区域的作用.
主要成果:
- 在trpR表达中,从0到+1读取的过渡是通过绕过一个55核酸 (nt) mRNA段而发生的.
- 这种绕过事件发生在翻译过程中,而不是之前.
- 需要两个相邻的元素:一个特定的trpR序列和一个先前的非特定的5'末端超过10个可翻译的编码子.
- 55-nt区域必须在0中翻译,以方便绕过进入+1.
结论:
- 翻译绕过是一种新发现的基因表达机制.
- 这些发现表明,可能存在转化性内子,类似于结合体内子.
- 这种机制为对 prokaryotes 中基因表达的调节提供了新的见解.
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