通过2'O-甲基化初始代子对翻译启动的有针对性的抑制
Emmely A Patrasso1,2, Hannah Serio1,2, Adam Suh1
1Department of Pharmacology. Feinberg School of Medicine. Northwestern University. Chicago, IL. USA.
bioRxiv : the preprint server for biology
|July 16, 2025
概括
传递 RNA (mRNA) 的化学修饰 2'O-甲基化 (Nm) 抑制了非正规起始编码子的翻译启动. 这一发现揭示了上游开放阅读框架 (uORF) 在人类细胞中是如何调节的.
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 基因表达
背景情况:
- 蛋白质合成通常始于AUG启动密码子.
- mRNA的5'未翻译区域 (5'UTR) 含有非正规的起始编码子,导致上游的开放阅读框架 (uORF).
- 控制非正规起始密码子选择的机制尚不清楚.
研究的目的:
- 为了研究非正规的启动密码子选择的机制.
- 确定调节非正典网站翻译启动的因素.
- 了解mRNA化学修饰在uORF表达中的作用.
主要方法:
- 翻译前启动复合体的结构分析.
- 识别和表征mRNA的化学修饰.
- 研究mRNA和18SrRNA之间的相互作用.
- 分析2'O-甲基化对翻译启动和uORF表达的影响.
主要成果:
- 开始编码子中的第一个核酸的2'OH组被18SrRNA识别,以实现最佳的启动.
- 确定了2'O-甲基化 (Nm) 作为一种抑制翻译启动的mRNA修饰.
- 2'O-甲基化干扰了mRNA-18SrRNA的相互作用,阻止了启动编码子的识别.
- 在5'UTR中证明了2'O-甲基化在非正规起始点的存在,抑制了上游翻译.
结论:
- 2'O-甲基化 (Nm) 在翻译启动中起着重要的调节作用.
- 这种修改有效地控制uORF表达,通过抑制非正规的启动码子使用.
- 提供了对人类细胞中非正规起始密码子选择机制的新见解.
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