翻译刺激:用于结合Com蛋白的RNA序列和结构要求
1Institut für Genbiologische Forschung Berlin GmbH, Federal Republic of Germany.
Cell
|April 19, 1991
概括
菌体Mu Com蛋白通过结合其转化启动区域 (TIR) 来增强母亲基因表达. 这种结合会诱导mRNA的结构变化,改善核糖体结合和翻译.
科学领域:
- 分子生物学分子生物学
- 细菌体遗传学 细菌体遗传学
- 基因规则 基因规则
背景情况:
- 菌体Mu的母亲基因表达对其生命周期至关重要.
- 已知菌体 Com 蛋白质可以积极调节母亲基因转换.
研究的目的:
- 为了研究Com蛋白刺激母亲基因表达的机制.
- 阐明mRNA结构和蛋白质结合在翻译控制中的作用.
主要方法:
- 在体外转录和翻译试验.
- 纯化和表征的Com蛋白质.
- 进行RNA足迹实验.
- 母体转化启动区域 (TIR) 的位点定向突变发生.
主要成果:
- 纯化Com蛋白在体外特别刺激基因表达.
- 康姆蛋白与母亲TIR中的特定部位结合.
- 结合会诱导母体TIR的形状变化,无论是体内还是体外.
- 突变分析证实了mRNA二次结构在翻译调节中的重要性.
结论:
- 康姆蛋白作为一种转化激活剂,用于菌体Mu mom基因.
- 与母体结合TIR改变mRNA构造,促进核糖体结合并增强翻译启动.
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