在酵母延长和启动tRNA中进行m1A58结合的不同修改途径
Marcel-Joseph Yared1, Yasemin Yoluç2, Marjorie Catala1
1Expression génétique microbienne, Université Paris Cité, CNRS, Institut de biologie physico-chimique, Paris, France.
Nucleic acids research
|August 31, 2023
概括
m1A58修饰对于启动器tRNAiMet结构和稳定性至关重要,防止其降解. 这项研究澄清了其早期的整合,独立于其他修改,解决了以前的不一致性.
科学领域:
- 分子生物学分子生物学
- 在RNA生物学,RNA生物学.
- 生物化学 生物化学
背景情况:
- 转移RNAs (tRNAs) 对蛋白质合成至关重要,并且需要广泛的转录后修改才能正常工作.
- 在tRNA生物发生和修改中的缺陷可以通过快速tRNA衰变 (RTD) 和核监测途径导致tRNA降解.
- 酵母tRNA中m1A58修饰的时间以前报告不一致,一些研究表明早期结合,而另一些研究则迟到了.
研究的目的:
- 为了协调关于m1A58在酵母中被纳入的时间性的相互矛盾的报告.
- 研究延长器tRNAPhe中 Ψ55 → T54 → m1A58修饰电路的分子控制.
- 确定m1A58对启动器tRNAiMet的结构影响及其在防止降解中的作用.
主要方法:
- 利用专门修改的酵母tRNA来研究序列修改途径.
- 分析了m1A58在延长和启动tRNA中的结合.
- 使用生物物理技术评估了具有或没有m1A58修饰的启动器tRNAiMet的结构性质.
主要成果:
- 证明m1A58有效地被纳入未经修改的启动器tRNAiMet,独立于先前的修改.
- 阐明了在延长子tRNA中控制 Ψ55 → T54 → m1A58 修饰电路的分子方面.
- 表明m1A58对于启动器tRNAiMet肘部结构的正确组装至关重要.
结论:
- m1A58修改很早就被纳入启动器tRNAiMet,而不考虑其他修改.
- m1A58的存在对启动器tRNAiMet的结构完整性至关重要,防止其通过降解途径识别.
- 这项研究为核监测和RTD介导的缺少m1A58.8的低基调启动器tRNA的核监测和RTD介导的降解提供了结构基础.
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