规范翻译因子eIF1A和eIF5B调节重复关联非AUG翻译的启动步骤
Hayato Ito1, Kodai Machida2, Yuzo Fujino3
1School of Life Science and Technology, Institute of Science Tokyo, S2-19, Nagatsuta 4259, Midori-ku, Yokohama 226-8501, Japan.
Nucleic acids research
|October 9, 2025
概括
在C9orf72中重复扩张会导致神经退行. 研究人员发现,转化启动因子-真核体启动因子1A (eIF1A) 和真核体启动因子5B (eIF5B) 抑制了这种非正规的重复关联非AUG (RAN) 转化.
科学领域:
- 分子生物学分子生物学
- 神经科学是一个神经科学.
- 遗传学 遗传学 是一个
背景情况:
- 核酸重复扩张,就像C9orf72中的GGGGCC重复一样,涉及到神经退行性疾病,如C9-ALS.
- 这些扩展导致重复关联的非AUG (RAN) 翻译,这是一个从所有读取框架中的非AUG编码器启动的非正规的翻译形式.
研究的目的:
- 为了确定RAN翻译的监管因素.
- 研究翻译启动因子在C9orf72介导的RAN翻译 (C9-RAN) 中的作用.
主要方法:
- 利用基于人体因素的重组细胞自由翻译系统来建模RAN翻译.
- 在HEK293T细胞中进行了翻译启动因子的淘汰实验.
- 研究了综合应激反应 (ISR) 在淘汰条件下对RAN转换的影响.
主要成果:
- 在无细胞系统中遗漏的真核启动因子1A (eIF1A) 或真核启动因子5B (eIF5B) 增强的C9-RAN,将其识别为抑制剂.
- 细胞中eIF1A和eIF5B的双重敲击进一步增加了C9-RAN,这表明在翻译启动中有不同的调节作用.
- eIF1A knockdown 取消了 RAN 翻译的 ISR 中介增强,表明它参与了这个途径.
结论:
- eIF1A和eIF5B作为C9orf72-介导的RAN转换的抑制剂.
- 这些因素通过翻译启动的不同步骤来调节C9-RAN.
- eIF1A在综合应激反应依赖的非AUG转换中起着至关重要的作用.
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