含有素的蛋白质eIF5A促进了翻译延长
Preeti Saini1, Daniel E Eyler, Rachel Green
1Laboratory of Gene Regulation and Development, NICHD, National Institutes of Health, Bethesda, Maryland 20892, USA.
Nature
|May 9, 2009
概括
翻译因子eIF5A含有独特的氨基酸素,对蛋白质合成至关重要. 这项研究表明,eIF5A通过帮助与eEF2.2一起的核糖体转移来促进翻译延长,而不是启动.
科学领域:
- 分子生物学分子生物学
- 蛋白质合成 蛋白质合成
- 遗传学 是一个遗传学.
背景情况:
- 像EF-Tu和EF-G这样的翻译延长因子对于蛋白质合成至关重要.
- 以前,人们认为eIF5A是一种独特的含有素的真核细胞因子,有助于启动翻译.
- 在细胞过程中eIF5A的确切功能仍然不清楚,与mRNA衰变和运输的联系.
研究的目的:
- 阐明转化因子eIF5A在细胞中的确切作用.
- 为了调查eIF5A是否在翻译启动或延长中起作用.
- 确定eIF5A影响蛋白质合成的机制.
主要方法:
- 在Saccharomyces cerevisiae中进行分子遗传研究.
- 生物化学分析,包括体外合成.
- 分析多体积累和核糖体过境时间.
- 禁用和耗尽eIF5A. 的功能.
- 测试复合eIF5A活动.
主要成果:
- 由于eIF5A的耗尽或失活,导致多体积累,并且在酵母体中增加了核糖体过渡时间.
- 重组eIF5A,但不是一个无的衍生品,增强了体外三合成.
- eIF5A无活化模仿了eEF2抑制剂sordarin的影响.
- eIF5A在结构上与细菌EF-P.相同.
结论:
- eIF5A是一种翻译延长因子,主要不涉及启动.
- eIF5A促进了核糖体转位,可能与eEF2合作.
- eIF5A/EF-P家族代表了一个普遍保留的翻译延长因子.
相关概念视频
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The transcription elongation is regulated via pausing of RNA polymerase on several occasions during transcription. In bacteria, these halts are necessary because the transcription of DNA into mRNA is coupled to the translation of that mRNA into a...
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