mRNA多A) 尾长对真核细胞转化阶段的影响
Nikita Biziaev1, Alexey Shuvalov1,2, Ali Salman1
1Engelhardt Institute of Molecular Biology, the Russian Academy of Sciences, 119991 Moscow, Russia.
Nucleic acids research
|June 14, 2024
概括
聚甲尾影响人类mRNA的翻译. 虽然顶部依赖的翻译大多独立于尾部长度,但顶部独立的翻译随着多个A尾部长度的增加而增加,这表明它在翻译调节中的作用.
科学领域:
- 分子生物学分子生物学
- 基因表达规范 基因表达规范
背景情况:
- 聚甲尾对mRNA稳定性和通过聚甲结合蛋白 (PABP) 的翻译至关重要.
- 聚甲尾长度对人类mRNA翻译效率的确切影响尚未完全阐明.
研究的目的:
- 为了研究不同多元A尾巴长度对人类mRNA翻译速率的影响.
- 了解多尾长如何影响顶部依赖和顶部独立的翻译.
主要方法:
- 在体外翻译试验中,使用细胞溶解物与具有明显多元A尾长的工程mRNA进行细胞溶解.
- 对翻译开始和结束阶段的分析.
主要成果:
- 顶部依赖的翻译是通过多的尾巴增强的,但在很大程度上对它的长度不敏感,除了75nt的尾巴.
- 顶部独立的翻译显示了与多元 (A) 尾巴长度的正相关.
- 多A尾部存在影响启动和终止,但不影响启动效率;较长的尾部通过eRFs增强基-tRNA水解.
结论:
- 一个75nt的多A尾可能对形成人类mRNA的双闭环结构至关重要.
- 这种结构可能会将翻译的启动和终止结合起来,从而影响整体的翻译效率.
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