相关实验视频

Updated: Jun 29, 2025

Monitoring eIF4F Assembly by Measuring eIF4E-eIF4G Interaction in Live Cells

Monitoring eIF4F Assembly by Measuring eIF4E-eIF4G Interaction in Live Cells

Published on: May 1, 2020

人类真核细胞启动因子4G直接与40S核糖体子单元结合,促进高效的翻译

Nancy Villa¹, Christopher S Fraser¹

¹Department of Molecular and Cellular Biology, College of Biological Sciences, University of California, Davis, California, USA.

The Journal of biological chemistry

|April 3, 2024

概括

细胞启动因子4G (eIF4G-RBD) 的RNA结合域刺激翻译独立于mRNA帽结合. 这项研究揭示了一种新的eIF4G与40S核糖体子单元的相互作用,增强了翻译启动.

科学领域:

分子生物学分子生物学
蛋白质-RNA 相互作用
翻译条例翻译条例翻译条例

背景情况:

使者RNA (mRNA) 招募到40S核糖体子单元对于翻译启动至关重要,主要由真核细胞启动因子4F (eIF4F) 复合体介导.
eIF4F复合体由eIF4E,eIF4A和eIF4G组成,eIF4G充当协调其他因素的支架,并通过eIF3.3将mRNA连接到40S子单元.
通过eIF4G结合RNA的特定功能及其对翻译启动的贡献仍然不完全理解.

研究的目的:

研究eIF4GRNA结合域 (eIF4G-RBD) 在刺激翻译中的作用.
阐明eIF4G-RBD影响翻译的机制,特别是其与规范上限依赖途径的独立性.
为了确定eIF4G与翻译机制之间的新型相互作用,特别是40S核糖体子单元.

主要方法:

使用eIF4G-依赖的翻译试验来评估eIF4G-RBD对翻译效率的影响.
采用动力螺旋酶测试来确定eIF4G-RBD对eIF4A螺旋酶活性的影响.
应用原生凝电泳和光极化试验,以调查eIF4G与40S核糖体亚单元之间的直接相互作用.

主要成果:

发现eIF4G-RBD (氨基酸682-720) 在与mRNA内部连接时显著刺激翻译,独立于m7G cap.
eIF4G-RBD对eIF4A螺旋酶活性的影响很小,这表明它主要不是协调双重解卷的功能.
发现了eIF4G和40S核糖体亚单元之间的新型直接相互作用,与已知的eIF4G-eIF3相互作用不同.

结论:

eIF4G-RBD在通过独立于cap-binding和mRNA tethering的机制促进翻译启动方面发挥着直接作用.
eIF4G利用不同的结合域与40S核糖体子单元相互作用,包括eIF3依赖和eIF3独立的通路.
这些发现揭示了eIF4F招聘40S子单位的更复杂模型,突出了翻译启动中的新型监管机制.

关键词:

有关RNA结合的RNA.eIF4F 是一个国际投资基金.eIF4G 是一个国际投资基金.它们是mRNARNA.开始翻译开始翻译

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