一个高度保守的真核蛋白家族,具有多链释放因子的特性
L Frolova1, X Le Goff, H H Rasmussen
1Department of Molecular Biology, University of Aarhus, Denmark.
Nature
|December 15, 1994
概括
科学家们确定了一个保存的蛋白质家族, eRF1,对于终止核生物中的蛋白质合成至关重要. 这一发现澄清了真核释放因子 (RF) 在翻译终结中的功能.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 生物化学 生物化学
背景情况:
- 蛋白质合成终结由停止编码子和释放因子 (RF) 调节.
- Prokaryotic 和线粒体 RF 的结构是已知的,但eukaryotic RF (eRF) 的结构是不清楚的.
- 一个单一的真核RF (eRF) 被识别,但它的身份和功能需要阐明.
研究的目的:
- 识别和描述参与翻译终结的真核释放因子 (eRF).
- 调查不同真核生物物种潜在的eRF的结构和功能相似性.
- 确认已识别的蛋白质在终止蛋白质合成中的作用.
主要方法:
- 序列分析以识别真核生物中保存的蛋白质家族.
- 候选蛋白质在酵母和大肠杆菌中的异质表达.
- 在体外释放因子测试测试蛋白质活性.
- 在翻译中对Saccharomyces cerevisiae sup45 (sup1) 的功能分析.
主要成果:
- 在较低和较高的真核生物中发现了一种保存的相关蛋白质家族,被指定为eRF1.
- 人类和Xenopus laevis eRF1蛋白在体外射频测定中得到表达,净化,并显示出活性.
- 作为eRF1家族的一部分,Saccharomyces cerevisiae蛋白 sup45 (sup1) 参与了翻译抑制.
- 在eRF1家族内观察到氨基酸序列的高保存在.
结论:
- 在真核生物中,eRF1蛋白家族直接参与转化终止.
- 在各种真核生物体中,eRF1蛋白在结构和功能上都保持稳定.
- 这一发现解决了关于真核细胞释放因子的身份和功能的长期问题.
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