翻译启动因子DHX29似乎在扫描方向相反的方向上拉动mRNA
Da Cui1,2, Tatyana Pestova3, Christopher Hellen3
1Structural Biology Initiative, CUNY Advanced Science Research Center, City University of New York, New York, NY, 10031, USA.
bioRxiv : the preprint server for biology
|August 12, 2025
概括
DExH盒子酶DHX29有助于在翻译启动过程中扫描mRNA. 新的结构模型揭示了DHX29的结构.
科学领域:
- 分子生物学分子生物学
- 结构生物学 结构生物学
- 生物化学 生物化学
背景情况:
- 在哺乳动物中,DExH盒子酶DHX29对于翻译启动至关重要.
- DHX29促进复杂的5'未翻译区域 (5'UTRs) 的信使RNA (mRNA) 的扫描.
- 对于DHX29在翻译启动过程中的作用的确切机制仍然不完全理解.
研究的目的:
- 阐明DHX29在翻译启动过程中作用的详细机制.
- 为DHX29与43S预启动复合体的交互提供一个精细的结构框架.
- 研究DHX29的活性调节及其在mRNA解中的作用.
主要方法:
- 使用结构建模与AlphaFold预测.
- 分析了DHX29与43S预启动复合体结合的冷电子显微镜 (cryo-EM) 结构.
- 整合结构数据,为DHX29函数提出机械模型.
主要成果:
- 一个修订后的结构框架阐明了DHX29,40S核糖体子单元和真核细胞启动因子3 (eIF3) 之间的相互作用.
- 40S核糖体子单元通过类似G贴片的机制调节DHX29的NTPase活性.
- 证据支持3'到5'转位酶机制,其中DHX29破坏mRNA干环的稳定,以促进扫描.
结论:
- 这项研究完善了对DHX29在翻译启动中的作用的理解.
- 拟议的模型突出了DHX29在解mRNA二次结构中的功能.
- 提出了关于DHX29在启动编码子选择方面的贡献的新假设.
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