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关于ESCRT系统的多样性,起源和演变
Kira S Makarova1, Victor Tobiasson1, Yuri I Wolf1
1National Center for Biotechnology Information, National Library of Medicine, Bethesda, Maryland, USA.
mBio
|February 21, 2024
概括
最后一个古老的共同祖先有一个复杂的内体排序复合物需要运输 (ESCRT) 系统参与蛋白质分类. 这种系统在各种考古群体中发生了不同的演变,阿斯加德考古物种与无处不在系统发展了联系.
科学领域:
- 细胞生物学 细胞生物学
- 进化生物学 进化生物学
- 生物化学 生物化学
背景情况:
- 运输所需的内体分类复合体 (ESCRT) 对真核细胞膜组织和蛋白质分类至关重要.
- 在古生物中发现ESCRT组件的同类物,特别是在阿斯加达古生物中,这是已知最接近于真核生物的古生物亲属.
- 在古生物中ESCRT系统的进化历史和完整范围仍然不完全理解.
研究的目的:
- 在古物种中全面搜索ESCRT蛋白质同类物.
- 通过遗传学分析和结构比较,重建ESCRT系统的进化轨迹.
- 阐明ESCRT复合体在古物中的祖先状态和多样化.
主要方法:
- 对Vps4 ATPase (ESCRT IV) 的遗传学分析,以构建ESCRT进化重建.
- 敏感蛋白序列分析以识别已知的和新的ESCRT同类.
- 结构模型的比较,以识别跨考古群体的功能上相似的领域.
主要成果:
- 在阿斯加德以外的古生物中发现了多种ESCRT系统,包括类似于ESCRT-I和ESCRT-II的蛋白质,这表明其起源很早.
- 在热蛋白质中发现了遥远的CdvA蛋白质同类物,可能与它们的细胞分裂有关.
- 重建了一个进化场景,其中最后一个古老的共同祖先拥有复杂的ESCRT系统用于蛋白质分类.
结论:
- 最后一个古老的共同祖先可能有一个复杂的ESCRT系统用于蛋白质分类.
- 考古物种的ESCRT进化有所不同,TACK的简化和阿斯加达考古物种的复杂化.
- 阿斯加达古 (Asgardarchaeota) 建立了ESCRT-ubiquitin系统连接,此前被认为是真核生物特有的特征.
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