单个mRNA分子体内翻译的动力学
Xiaowei Yan1, Tim A Hoek2, Ronald D Vale1
1Department of Cellular and Molecular Pharmacology, Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, CA 94158-2517, USA.
Cell
|May 7, 2016
概括
研究人员开发了一种新方法,可以在活细胞中观察单个mRNA转化超过一个小时. 这种技术揭示了同一细胞内单个信使RNA的蛋白质生产的显著差异.
科学领域:
- 分子生物学
- 细胞生物学
- 生物化学
背景情况:
- 细胞蛋白质水平由mRNA转化,即由核糖体将信使RNA (mRNA) 解码为多的过程来调节.
- 现有的方法缺乏实时观察单个mRNA的完整翻译过程.
研究的目的:
- 开发和应用一种新的长期成像技术,用于观察活细胞中的单个mRNA转化动态.
- 在mRNA转换过程中量化测量核糖体启动,延长和停滞.
- 在同一细胞内的单个mRNA分子之间研究翻译效率的异质性.
主要方法:
- 开发了一种长期 (> 1小时) 活细胞成像方法来追踪单个mRNA分子的翻译.
- 能够对关键的转化参数进行定量测量,包括启动,延长和核糖体停滞.
- 应用该方法研究细胞循环基因Emi1,专注于5'非翻译区域 (UTR) 调节元素.
主要成果:
- 在活细胞中观察到每一个mRNA分子的数百个翻译回合.
- 在单个mRNA分子的翻译效率中发现了显著的异质性,包括在活跃和不活跃的翻译状态之间快速,可逆的切换.
- 鉴定了Emi1基因中特定的5' UTR序列对翻译启动的强烈抑制,尽管单个mRNA水平的可变性.
结论:
- 开发的成像方法为活细胞中单个mRNA翻译动态提供了前所未有的视角.
- 这种方法揭示了在单个分子水平上以前未被重视的异质性和转化动态调节.
- 提供了一个强大的新工具来研究翻译调节的复杂性及其对细胞功能的影响.
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