在活细胞和神经元中单个mRNA的翻译动态
Bin Wu1, Carolina Eliscovich2, Young J Yoon3
1Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx, NY 10461, USA. Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
Science (New York, N.Y.)
|June 18, 2016
概括
科学家们开发了新生的单分子成像 (SINAPS) 以可视化活细胞中的蛋白质合成. 这种新方法追踪翻译启动,延伸和位置,揭示蛋白质是如何以及在哪里制成的.
科学领域:
- 分子生物学
- 细胞生物学
- 生物物理
背景情况:
- 翻译,即从mRNA合成蛋白质,对于所有生命至关重要.
- 虽然使用单分子成像研究了RNA转录动态,但活细胞中的翻译动态在很大程度上尚未可视化.
- 现有的方法缺乏能够实时观察活细胞中的个体翻译事件的分辨率.
研究的目的:
- 开发一种用于可视化和分析活细胞中单个mRNA转化动态的新技术.
- 直接测量翻译的关键方面,包括启动,延长和亚细胞局部化.
- 在不同细胞环境中研究蛋白质合成的时空调节.
主要方法:
- 开发和应用新生的单分子成像技术 (SINAPS).
- 使用光漂白后单分子光回收 (SMFRAP) 来量化翻译延长速度.
- 观察初级神经元中的mRNA转化动态以及与内质网膜的关系.
主要成果:
- SINAPS可直接观察活细胞中单个mRNA的翻译启动,延长和定位.
- 在遇到ER膜时,编码内质网膜 (ER) 蛋白的mRNA被翻译.
- 翻译延长速度是每秒大约5个氨基酸.
- 在初级神经元中,mRNA翻译发生在近端树突中,但在远端树突中被抑制,呈现出"爆发"模式.
结论:
- SINAPS是一种强大的新技术,用于研究活细胞中单个mRNA翻译的时空机制.
- 这些发现为单个分子水平的蛋白质合成提供了新的见解.
- 这种技术为研究各种生物过程和疾病的翻译缺陷打开了道路.
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