核糖体组装因子Reh1从多类出口道中释放,这是翻译的先驱轮
bioRxiv : the preprint server for biology
|November 14, 2023
概括
核糖体组装因子Reh1与60S子单元保持在早期的翻译中. 它是由延长型释放出来的,标记它为最后的组装因子,离开新生的60S子单元.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 生物化学 生物化学
背景情况:
- 核糖体生物生成对于蛋白质合成和细胞生长至关重要.
- 雷赫1是一种核糖体组装因子,在细胞质成熟晚期与60S前子单元结合.
- 雷赫1的C端插入到60S前子单元的多退出道 (PET).
研究的目的:
- 研究Reh1在核糖体组装和功能中的作用.
- 为了确定Reh1是否在Tif6释放和子单元连接后仍然与60S子单元相关.
- 为了理解ReH1在翻译的先驱阶段的解离动态.
主要方法:
- 选择性核糖体概况分析
- 单粒子冷电子显微镜 (冷电子显微镜)
- 生物化学试验用于研究蛋白质-亚单元相互作用.
主要成果:
- Reh1结合的60S子单元与40S子单元结合,形成活跃翻译80S核糖体.
- 结合Reh1的核糖体被丰富了接近启动的编码子和启动器tRNA,表明早期的翻译.
- 克里奥EM显示,与Reh1结合的80S核糖体含有A位点基tRNA,P位点tRNA和eIF5A,在早期延长过程中持续存在.
结论:
- 通过加入子单位和进入先驱翻译轮的早期阶段,Reh1仍然与60S子单位有关.
- Reh1被延长的链所取代.
- 在第一个翻译周期中,Reh1是从新生的60S子单元中释放的最后一个核糖体组装因子.
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