eIF4A3和eIF3g之间的相互作用驱动了翻译的内部启动
Jeeyoon Chang1, Min-Kyung Shin2, Joori Park2
1Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea.
Nucleic acids research
|October 9, 2023
概括
这项研究揭示了循环RNAs (circRNAs) 如何启动内部翻译. 它确定了eIF4A3和eIF3g之间的关键相互作用,使circRNAs的蛋白质合成成为可能,扩大了人类转录组已知的蛋白质编码潜力.
科学领域:
- 分子生物学分子生物学
- 在RNA生物学,RNA生物学.
- 基因表达规范 基因表达规范
背景情况:
- 内部翻译启动对于蛋白质合成至关重要.
- 循环RNAs (circRNAs) 越来越多地被认为是它们在内部翻译中的作用.
- 控制circRNAs内部翻译启动的精确机制尚未完全理解.
研究的目的:
- 阐明circRNAs内部翻译启动的分子机制.
- 为了确定参与circRNA介导翻译的关键蛋白质因素.
- 为了研究外结复合体 (EJC) 在circRNA转化中的作用.
主要方法:
- 蛋白与蛋白相互作用测试以确定eIF4A3.3.的结合伙伴.
- 在体外翻译测试使用合成的circRNAs.
- 对内源性circRNAs的多体关联进行了全转录组分析.
- 西方斑点分析检测蛋白质表达.
主要成果:
- eIF3g是eIF3综合体的一个子单元,被确定为eIF4A3.3的绑定合作伙伴.
- eIF4A3和eIF3g之间的相互作用作为分子链接器,促进内部核糖体的进入.
- eIF4A3以eIF3g-依赖的方式驱动来自circRNA的内部翻译.
- 内源性circRNAs的高效多体关联需要eIF4A3.3.
- 一个circRNAs的子集可以表达全长蛋白质,如β-catenin,依赖eIF4A3.3.
结论:
- eIF4A3-eIF3g相互作用是circRNAs上内部翻译启动的关键决定因素.
- eIF4A3在内源性circRNAs的翻译中发挥着重要作用.
- 这项研究扩大了对circRNAs和人类转录组的蛋白质编码潜力的理解.
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