在全长蛋白质合成过程中量化延长节奏
Gabriel Rosenblum1, Chunlai Chen, Jaskiran Kaur
1Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, USA.
Journal of the American Chemical Society
|July 5, 2013
概括
核糖体暂停控制蛋白质合成节奏. 单分子弗斯特共振能量转移 (smFRET) 揭示了转移RNA (tRNA) 选择如何影响蛋白质合成速度和节奏,影响蛋白质折叠和修饰.
科学领域:
- 分子生物学分子生物学
- 生物物理学的生物物理.
- 遗传学 是一个遗传学.
背景情况:
- 核糖体暂停对于调节蛋白质合成和确保适当的蛋白质形成至关重要.
- 影响这些暂停的突变会导致蛋白质错误折叠和人类疾病.
- 传统的组合方法难以分析微妙的暂停,需要先进的单分子技术.
研究的目的:
- 为了研究编码子和转移RNA (tRNA) 在调节蛋白质合成延长率中的作用.
- 量化评估tRNA丰度对蛋白质合成动态的影响.
- 探索tRNA选择对蛋白质折叠和修饰等共同翻译过程的影响.
主要方法:
- 使用单分子Förster共振能量转移 (smFRET) 来实时监测蛋白质表达.
- 研究了一种全长蛋白质的合成,特别是绿色光蛋白 (GFP) 变体.
- 测量的延长率与编码子使用率和异接收器tRNA可用性相关联.
主要成果:
- 证明了蛋白质延长率与特定子及其相关tRNAs的使用之间的显著相关性.
- 量化估计了替换丰富的tRNA识别编码子以同义的,更罕见的tRNA编码子对延长率的影响.
- 提供了tRNA选择作为蛋白质合成速率和节律的关键调节器的证据.
结论:
- tRNA选择是调节蛋白质合成速度和节奏的关键因素.
- 这些发现表明tRNA的可用性可以影响同时发生的共同翻译事件,包括蛋白质折叠和化学修饰.
- 单分子方法对于特征蛋白质合成中微妙的暂停是有效的,这些暂停会影响细胞功能和疾病.
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