AAA+ SPATA5复合体的冷EM结构及其在人类细胞质60S前成熟中的作用
Yuhao Dai1,2, Damu Wu1,2, Ningning Li1
1State Key Laboratory of Membrane Biology, Peking-Tsinghua Joint Center for Life Sciences, School of Life Sciences, Peking University, Beijing, China.
Nature communications
|April 23, 2025
概括
人类SPATA5蛋白质复合物通过释放60S前颗粒的因子来帮助核糖体组装. 一个冷EM结构揭示了人类特异性相互作用,为核糖体生物发生提供了治疗点.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 结构生物学 结构生物学
背景情况:
- 核糖体生物生成对细胞功能至关重要,涉及许多依赖ATP的步骤.
- 在酵母中,AAA+ ATPase Drg1从细胞质中的前-60S颗粒中释放Rlp24.
- 人类同类物,SPATA5和相关因素都参与了类似的过程,但机制尚不清楚.
研究的目的:
- 阐明人类60S前核糖体粒子细胞质成熟的分子机制和结构基础.
- 描述SPATA5复合物的组成及其与60S前粒子的相互作用.
主要方法:
- 复杂的净化和静脉测量测定.
- 电子显微镜 (cryo-EM) 用于结构分析.
- 生物化学测定用于研究ATPase活性和蛋白质相互作用.
主要成果:
- 与SPATA5L1,C1orf109和CINP一起,SPATA5形成了一个异构体复合体 (4:2:2:2),具有不同的N终端和AAA+ ATPase环.
- 在SPATA5中,一种保存的氨酸 (C672) 被硫化,导致一个不活跃的ATP结合形状.
- 结冷EM显示,人类特异性因子CINP通过与GTPBP4和ES27A的相互作用来调解60S前粒子识别.
结论:
- 这项研究为了解人类细胞质前-60S成熟的结构框架.
- 涉及CINP的人类特异性互动突出了这一过程的独特方面.
- 这些发现提供了与核糖体生物发生有关的潜在治疗点.
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