萨卡罗洛布斯 (Saccharolobus solfataricus) 启动复合体的结构与无领导的mRNA突出显示了古老特征和真核生物的接近性
Gabrielle Bourgeois1, Pierre-Damien Coureux1,2, Christine Lazennec-Schurdevin1
1Laboratoire de Biologie Structurale de la Cellule (BIOC), CNRS, Ecole polytechnique, Institut Polytechnique de Paris, Palaiseau, 91120, France.
Nature communications
|January 3, 2025
概括
古代核糖体具有共享的真核特征,与特定的蛋白质,如eS25,eS26和eS30在真核的近亲发现. 这项研究揭示了它们在Saccharolobus solfataricus无领导信使RNA (mRNA) 的翻译中的作用.
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:
- 古代的核糖体表现出真核细胞的特征.
- 塔克和阿斯加德古生物学家拥有其他古生物学家缺少的真核核核糖体蛋白 (eS25,eS26,eS30).
- 了解考古翻译机制为我们提供了关于真核生物起源的见解.
研究的目的:
- 为了研究Saccharolobus solfataricus小核糖体子单元的结构和功能.
- 描述无领导和SD领导的信使RNAs (mRNAs) 与古人类核糖体的结合.
- 探索古生物和真核生物转换之间的进化关系.
主要方法:
- 电子显微镜 (Cryo-EM) 用于确定高分辨率结构.
- 核糖体子单元的生物化学表征.
- 对信使RNA (mRNA) 结合相互作用的分析.
主要成果:
- 化EM结构显示了eS25,eS26和eS30与S. solfataricus的小核糖体子单元结合.
- 确定了两种新的古老核糖体蛋白,aS33和aS34,以及eS6的额外域.
- 无领导的mRNA通过其5'-三酸盐组结合,eS26在mRNA退出通道中发挥作用,与Shine-Dalgarno双重组不相容.
结论:
- 古代的eS26蛋白在mRNA输出通道中占据着与其真核生物对应物相似的位置.
- 这种定位表明eS26在无领导的mRNA翻译中的作用,并提供了古生物和真核生物翻译之间的进化联系的证据.
- 这些发现揭示了翻译机械从古生物到真核生物的演变.
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