核糖体出口道的功能是区分门
Hitoshi Nakatogawa1, Koreaki Ito
1Institute for Virus Research and CREST, Japan Science and Technology Corporation, Kyoto University, Japan.
Cell
|March 15, 2002
概括
由于特定的核糖体停止动机,SecM的翻译停滞不前. 核糖体组件中的抑制器突变表明,出口道作为新生蛋白质产品的门.
科学领域:
- 分子生物学分子生物学
- 蛋白质合成 蛋白质合成
- 核糖体功能 核糖体功能
背景情况:
- SecM是一种蛋白质,其翻译是由蛋白质出口机制调节的.
- 从核糖体中出现的新生蛋白质链可以与核糖体出口道相互作用.
- 翻译逮捕的确切机制及其监管尚未得到充分理解.
研究的目的:
- 为了调查SeCM翻译的机制.
- 为了确定参与调节SecM翻译的核糖体组件.
- 阐明核糖体出口道在新生的蛋白质产品歧视中的作用.
主要方法:
- 局部定向突变发生,引入SecM和核糖体组件中的突变.
- 在体外翻译试验检测监测蛋白质合成和延长停止.
- 对23S核糖体RNA (rRNA) 和核糖体蛋白L22中的抑制突变进行分析.
主要成果:
- 在SecM中,一个特定的序列基因 (FXXXXWIXXXXGIRAGP) 含有proline残留物,会在核糖体内诱导延长停止.
- 确定了23SrRNA和核糖体蛋白L22中的突变,可以抑制这种延长停止.
- 这些抑制器突变映射到沿着核糖体出口道最狭窄部分的残留物.
结论:
- 识别的序列图案在翻译过程中起到作为特定的停止点的作用.
- 核糖体出口道的狭窄收缩在感知和响应新生的多链方面发挥着至关重要的作用.
- 核糖体的这一区域起到区分门的作用,根据蛋白质的序列和结构控制蛋白质的通过.
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