细菌伴侣触发因子的动态结合,以转化Escherichia coli中的核糖体
Tora Hävermark1, Mikhail Metelev1, Erik Lundin1
1Department of Cell & Molecular Biology, Uppsala University, Uppsala SE-75124, Sweden.
概括
细菌触发因子 (TF) 动态地与大肠杆菌中的翻译核糖体结合,短时间的结合事件影响蛋白质折叠. TF与信号识别粒子 (SRP) 竞争,调节SRP.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 生物物理学的生物物理.
背景情况:
- 触发因子 (Trigger Factor,TF) 是一种细菌伴侣,有助于共翻译蛋白折叠.
- 之前关于TF-RNC相互作用的研究使用了非生理条件,产生了相互矛盾的数据.
- 在体内,TF与其他因素 (如SRP) 的动态和竞争仍然不清楚.
研究的目的:
- 为了研究TF在活体中结合到活跃翻译核糖体的动态.
- 了解TF和SRP在核糖体新生链复合体 (RNC) 结合方面的竞争.
- 阐明TF在调制SRP结合选择性的作用.
主要方法:
- 单颗粒追踪 (SPT) 用于监测活体大肠杆菌中TF与核糖体的结合.
- 在细胞环境中实时分析了TF-RNC相互作用.
- 对RNCs的TF和SRP之间的竞争动态进行了评估.
主要成果:
- 在体内,TF对RNCs表现出不同的结合模式:更长 (大约2个小时). 1秒) 和更短 (大约1秒) 的时间. 50 ms) 的时间.
- TF 结合是高度动态的,有暂时的自由状态 (约. 40个小时).
- 在RNC绑定方面,TF与SRP竞争,改变了SRP的选择性.
结论:
- 在体内,TF与RNC的相互作用是短暂的,仅占据翻译周期的一小部分.
- TF的动态结合和解结合循环对其功能至关重要.
- TF作为RNC竞争中的监管机构,影响SRP介导的准.
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