从U到mnm5Se2U:通过2-素和5-甲基胺甲基修改调基配对偏好
Paulina Kuwerska1, Katarzyna Kulik2, Karolina Podskoczyj1
1Institute of Organic Chemistry, Faculty of Chemistry, Lodz University of Technology, Zeromskiego 116, Lodz, 90-924, Poland.
Scientific reports
|December 30, 2025
概括
细菌tRNA中的修饰性尿素,如2-thiouridine和2-selenouridine,会影响代码子的识别. 这项研究揭示了5-甲基胺甲基 (mnm5) 和素修饰如何影响RNA双重稳定性和基配对特异性.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 化学生物学 化学生物学
背景情况:
- 波动定位的tRNA修饰,包括5-置换的尿素,2-thiouridines和2-selenouridines,在细菌中至关重要.
- 5-甲基米甲基 (mnm5) 替代物广泛存在,影响了编码子的识别,但其与2-基因修饰的相互作用尚未完全理解.
- 改性核化物增强治疗核酸的稳定性和特异性,需要更深入地了解它们的结构和热力学效应.
研究的目的:
- 系统地研究5-methylaminomethyl (mnm5) 和2-chalcogen (O2,S2,Se2) 修饰对RNA复杂性质的热力学和结构性贡献.
- 阐明在mnm5替代剂存在时对RNA双重稳定性和基配对特异性的素效应.
- 探索这些修改对识别纯氨酸终结型编码子的影响.
主要方法:
- 十七种基对RNA复合体的热力学和结构分析.
- 合成含有 uracil,2-thiouridine (S2U),2-selenouridine (Se2U) 和它们的5-methylaminomethyl (mnm5) 替代类型 (mnm5U, mnm5S2U, mnm5Se2U) 的RNA复合体.
- 循环二元化 (CD) 光谱学以表征RNA双重结构和mnm5Se2U修饰RNA寡合体的化学合成.
主要成果:
- 炭基基因与腺调节双重复合稳定性:U < Se2U < S2U;mnm5替代剂显著破坏双重复合的稳定性.
- 在与guanosine的双重复合中,Se2-uridines比2-thio或2-oxo对应物更容易促进双重复合的形成,这可能是由于更高的电离倾向.
- 对于A对G的基配对特异性是这样的:U < Se2U < S2U;mnm5-尿氨酸减少了纯氨酸核酸之间的区别.
- 所有的RNA复合体都通过CD光谱显示了A-RNA螺旋结构.
结论:
- 5 - 甲基氨基甲基 (mnm5) 替代剂通常会破坏RNA复合体的稳定,并减少基配对的歧视.
- 2-uridine和2-thiouridine的修饰不同影响RNA双重稳定性和基配对的特异性,而2-selenouridine与瓜诺辛增强了双重形成.
- 该研究提供了mnm5Se2U修饰RNA寡合体的第一个化学合成,促进了对核酸化学和治疗学中修饰核酸的理解和应用.
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