触发因素加快了新生链条的紧缩和折叠
Katharina Till1, Anne-Bart Seinen1, Florian Wruck1
1AMOLF, Amsterdam 1098 XG, Netherlands.
概括
触发因子伴侣加速新生的链条直接在核糖体上折叠. 这种共翻译折叠会影响蛋白质的组装和聚合.
科学领域:
- 分子生物学分子生物学
- 生物物理学的生物物理.
背景情况:
- 在核糖体的新生链形状控制是不太了解.
- 护航者通常远离核糖体起作用,但在翻译过程中会出现蛋白质折叠的挑战.
研究的目的:
- 研究大肠杆菌伴侣触发因子 (TF) 在新生链在核糖体上的结构控制中的作用.
- 阐明TF在翻译过程中影响蛋白质折叠的机制.
主要方法:
- 选择性核糖体造型结合光学子和单分子光.
- 使用二叶酸减少酶 (DHFR) 作为模型系统.
主要成果:
- 触发因子 (TF) 已被证明可以加速在核糖体上新生的链条折叠.
- 由于新生的链条折叠和崩,TF表现出短暂的扫描,随后是稳定的结合.
- TF结合诱导新生的链崩,稳定部分折叠,压缩延长TF结合.
- TF加速折叠取决于蛋白质结构至关重要的特定片的出现.
结论:
- 触发因子在促进核糖体的共翻译折叠方面发挥着至关重要的作用.
- 通过TF介导的折叠加速影响共翻译蛋白组合,聚合和翻译暂停.
- 这些发现表明TF在整个生命中对蛋白质生物发生的重要性.
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