eEF2二胺修饰抑制了虚假的移,以保持翻译忠实度.
Byung-Sik Shin1, Ivaylo P Ivanov1, Joo-Ran Kim1
1Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
Nucleic acids research
|May 29, 2023
概括
翻译因子eEF2上的二胺修饰对于保持翻译忠实性至关重要,防止核糖体框架转移和过早终止. 它的缺失会损害蛋白质合成的准确性,尽管它对细胞存活不至关重要.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 生物化学 生物化学
背景情况:
- 双胺 (DPH) 是延长因子2 (eEF2) 的一种独特的翻译后修饰.
- DPH对抗细菌毒素的抗性至关重要,但其精确的细胞功能尚不清楚.
- 在真核生物中,DPH通过复杂的酶途径合成.
研究的目的:
- 为了研究二胺 (DPH) 修饰的细胞功能.
- 描述 DPH 缺陷对翻译精度和细胞过程的影响.
- 了解DPH的进化意义.
主要方法:
- 对缺乏DPH的Saccharomyces cerevisiae突变物的分析.
- 酵母和哺乳动物细胞中的核糖体概况.
- 评估核糖体框架转移和mRNA翻译延长.
- 研究DPH ADP-ribosylation对eEF2-核糖体相互作用的影响.
主要成果:
- 失去DPH会增加对索达林的抵抗力,并增强-1核糖体框架转移.
- DPH 缺乏导致核糖体下降的增加和过早终止.
- DPH的ADP-ribosylation阻碍了eEF2与核糖体的结合,从而损害了翻译.
- 移除框架外的停止子可以挽救长mRNA上的核糖体过程性.
结论:
- 在延长过程中维护翻译忠实性,二胺基修饰至关重要.
- 失去DPH会导致广泛的核糖体框架转移和过早终止.
- DPH很可能是为了确保精确的蛋白质合成而进化,尽管它对毒素很脆弱.
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