在受阻转位期间通过动力分区进行编程-1转移
Neva Caliskan1, Vladimir I Katunin2, Riccardo Belardinelli1
1Max Planck Institute for Biophysical Chemistry, Department of Physical Biochemistry, 37077 Göttingen, Germany.
Cell
|June 21, 2014
概括
编程的-1核糖体框架转移 (-1PRF) 允许细胞扩展基因组信息并调节基因表达. 这项研究揭示了-1PRF发生在翻译延长的晚期,受mRNA结构和核糖体动态的影响.
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:
- 编程的-1核糖体框架转移 (-1PRF) 是一个关键的mRNA重编码机制.
- 它增强了基因组信息内容,并调节了基因表达.
- 在翻译延长过程中-1PRF的精确时间和机制仍然不完全理解.
研究的目的:
- 阐明控制编程-1核糖体框架转移的逐步机制.
- 在翻译延长过程中确定1PRF的时间.
- 调查mRNA二次结构的作用,如伪结,在调节-1PRF.
主要方法:
- 使用了从大肠杆菌 (Escherichia coli) 中复制的体外翻译系统.
- 采用了从IBV 1a/1b基因中获得的模型mRNA.
- 追踪了通过框架转移部位的核糖体逐步运动.
主要成果:
- 确定了框架转移作为晚期转位事件.
- 证明当tRNAs占据相邻的滑动子时,就会发生移.
- 表明下游的伪结阻碍了30S子单元的头部关闭,EF-G解离和tRNA释放.
- 发现,核糖体滑入-1加速转位完成,有利于新的读取.
结论:
- 编程-1核糖体框架转移是一种调节的过程,发生在翻译延伸的晚期.
- mRNA二次结构显著影响移动的动力学.
- 核糖体动力学和与延长因子的相互作用对-1PRF效率至关重要.
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