人类核和线粒体tRNA 3'处理的分子基础
Arjun Bhatta1,2,3, Bernhard Kuhle1,2, Ryan D Yu1,2,3
1Department of Cellular Biochemistry, University Medical Center Göttingen, Göttingen, Germany.
Nature structural & molecular biology
|January 2, 2025
概括
人类ELAC2酶过程转移RNA (tRNA) 前体. 对于线粒体tRNAs (mt-tRNAs),它需要TRMT10C和SDR5C1,特别是对于结构异常的mt-tRNAs,揭示了对tRNA成熟的新见解.
科学领域:
- 分子生物学分子生物学
- 处理RNA处理RNA处理
- 线粒体生物学 线粒体生物学
背景情况:
- 细胞转移RNA (tRNA) 前体需要精确的加工才能成熟.
- 酶ELAC2对于人类的核编码 (nu-tRNAs) 和线粒体编码 (mt-tRNAs) tRNA的3'端处理至关重要.
- 对于nu-tRNA处理,ELAC2的功能是独立的,但在大多数mt-tRNA处理中需要辅助因素.
研究的目的:
- 阐明ELAC2介导的tRNA3'末端处理背后的分子机制,特别是在线粒体中.
- 确定TRMT10C和SDR5C1在处理结构退化的mt-tRNA中的特定作用.
- 为器官特异性tRNA成熟路径提供结构基础.
主要方法:
- 采用X射线晶体学来确定ELAC2与TRMT10C,SDR5C1和mt-tRNA基质复合的结构.
- 参与tRNA识别的蛋白质-RNA和蛋白质-蛋白质相互作用的比较分析.
- 研究TRMT10C-SDR5C1在补偿mt-tRNA结构变异中的功能意义.
主要成果:
- 特别地,TRMT10C和SDR5C1促进了缺乏正规肘结构的mt-tRNA的处理.
- 确定了两个不同的tRNA前识别机制:对正规tRNA的直接ELAC2-RNA相互作用和对非正规mt-tRNA的ELAC2-TRMT10C蛋白质-蛋白质相互作用.
- 结构数据揭示了TRMT10C和SDR5C1如何作为线粒体tRNA成熟平台.
结论:
- 这项研究为tRNA 3'处理在核和线粒体中提供了分子基础.
- 这些发现解释了在mt-tRNA处理中对TRMT10C和SDR5C1等额外因素的有机细胞特异性要求.
- TRMT10C-SDR5C1很可能进化为处理在双边动物中普遍存在的结构性损害mt-tRNAs.
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