哺乳动物氨酸tRNA修改影响翻译以增强细胞增殖和MHC-II表达
Olivia N P Zbihley1, Katherine Johnson2, Luke R Frietze1
1Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL 60637, USA.
Journal of molecular biology
|May 8, 2025
概括
在转移RNA (tRNA) 中高水平的queuosine (Q) 修饰增强了人类和小鼠细胞的细胞增殖. 这种tRNA修饰影响基因表达和免疫反应,为各种生物功能提供了洞察力.
科学领域:
- 分子生物学分子生物学
- 基因组学就是基因组学.
- 免疫学 免疫学 免疫学
背景情况:
- 奎素 (Q) 是一个关键的tRNA修改在摇摆的反位,对于解码特定的子至关重要.
- 细胞的Q-修饰依赖于代谢物队列和QTRT1/QTRT2酶复合体.
- 虽然Q-修饰影响了翻译效率,但它对哺乳动物细胞增殖和转录组的影响仍未得到充分研究.
研究的目的:
- 研究tRNA Q-修饰水平在哺乳动物细胞增殖中的作用.
- 阐明与改变的Q-修饰相关的分子机制,包括转录组和tRNAome变化.
- 检查Q修饰对基因表达和细胞功能的上下文依赖影响.
主要方法:
- 对人类HEK293T细胞和来自小鼠骨髓的树突细胞 (BMDCs) 的比较分析,具有不同的tRNA Q-修饰水平.
- 使用了包括tRNA-seq和mRNA-seq在内的高通量测序技术.
- 进行了的使用分析和表面蛋白质呈现的评估 (MHC-II).
主要成果:
- 提升的tRNA Q-修饰水平与HEK293T细胞和BMDC的增多率相关.
- 在Q-修改和m22GtRNA修改之间观察到正相关性,表明增强的翻译效率.
- 情境依赖的转录组变化:HEK293T细胞显示了对代谢过程和信号的调节,而BMDCs显示了免疫反应,增殖和免疫球蛋白多样化的变化.
结论:
- tRNA Q-修改显著提高哺乳动物细胞增殖,可能通过改进的核糖体蛋白转化.
- Q-修饰会影响不同的细胞通路,包括免疫反应调解和BMDC中的免疫球蛋白多样化.
- 这项研究强调了tRNA Q-修饰在各种生物功能,包括免疫细胞功能中的更广泛的调节作用.
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