古代核糖体的结构揭示了不同的活性部位和冬眠因子
Amos J Nissley1, Yekaterina Shulgina2,3,4, Roan W Kivimae1
1Department of Chemistry, University of California, Berkeley, Berkeley, CA, USA.
Nature microbiology
|July 17, 2025
概括
古代古生物学上的核糖体在它们的蛋白质制造机械 (基转移酶中心) 中显示出令人惊的多样性. 这项研究揭示了调节核糖体功能的新型因素,并突出了这些必不可少的细胞组成部分的进化变异.
科学领域:
- 分子生物学分子生物学
- 结构生物学 结构生物学
- 进化生物学 进化生物学
背景情况:
- 核糖体对于蛋白质合成至关重要,将mRNA转化为蛋白质.
- 核糖体内的基转移酶中心 (PTC) 对于催化是至关重要的,并且在整个进化过程中通常被认为是高度保守的.
- 与细菌和真核生物对应物相比,古生物学上的核糖体表现出独特的结构和序列特征.
研究的目的:
- 调查古人类基转移酶中心 (PTC) 序列分离的结构基础.
- 了解古代核糖体RNA (rRNA) 和核糖体蛋白质变异的功能影响.
- 识别和描述参与调节古老核糖体功能的新型因素.
主要方法:
- 使用冷电子显微镜 (cryo-EM) 来确定来自超热友的古生物Pyrobaculum calidifontis的70S和50S核糖体的高分辨率结构.
- 对核糖体RNA和蛋白质序列的分析,以确定PTC的变异.
- 已识别的核糖体相关因子的生物化学表征.
主要成果:
- 在PTC中识别了具有高度分歧的rRNA序列的古老基团.
- 低温EM结构揭示了PTC序列的变化如何导致关键基三倍的重新排列.
- 考古和细菌核糖体蛋白质的差异促进了考古PTC的序列变化.
- 发现了一种新型的古代核糖体冬眠因子Dri,与已知的细菌和真核生物因子不同.
结论:
- 考古PTC表现出比以前假设的更大的序列和结构多样性.
- 古代核糖体蛋白质在适应PTC序列变异方面发挥着作用.
- 一种新型的冬眠因子Dri调节了古生物中的核糖体功能,这表明了整个类的多种调节机制.
- 这项研究扩大了我们对核糖体进化和古生物的功能多样性的理解.
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