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In Vitro Polymerization of F-actin on Early Endosomes
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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, MD 20894, USA.
bioRxiv : the preprint server for biology
|June 21, 2024
概括
运输所需的内体组分复合体 (ESCRT) 系统可能起源于最后的古老共同祖先,复杂的版本在阿斯加达古和其他古物中演变为更简单的形式. 这个系统早于真核生物和细菌.
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:
- 运输所需的内体组分类复合体 (ESCRT) 对于真核生物中的蛋白质分类至关重要.
- 在古生物中发现ESCRT同类物,特别是在阿斯加达古生物中,这是最接近于真核生物的古生物亲属.
- 细菌缺乏可识别的ESCRT组件.
研究的目的:
- 在古物种中全面搜索ESCRT蛋白质同类物.
- 重建ESCRT系统的演化历史.
- 为了调查真核生物ESCRT复合体的起源.
主要方法:
- 敏感蛋白序列分析.
- 结构模型的比较.
- 使用Vps4 ATPase (ESCRT IV) 作为支架的遗传学分析.
主要成果:
- 在阿斯加德以外的古生物中确定了多种ESCRT系统,包括类似于真核生物ESCRT-I和ESCRT-II的蛋白质.
- 在热蛋白质中发现了遥远的CdvA同类物,这表明它在细胞分裂中发挥了作用.
- 揭示了阿斯加达古 possess ESCRT 复合体与泛素系统相关,此前认为是唯一的真核生物特征.
结论:
- 最后的考古共同祖先可能有一个复杂的ESCRT系统用于蛋白质分类.
- 细胞ESCRT很可能是从祖先的考古建筑块进化出来的.
- 考古物中的ESCRT进化涉及简化 (例如,TACK) 或复杂化 (例如,Asgardarchaeota).
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