在克拉特林介导的内细胞分裂过程中,Epsin1对无处不在的货物强制执行一种依赖于凝结的检查点
Susovan Sarkar1, Hao-Yang Liu1, Feng Yuan1
1Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX, United States.
bioRxiv : the preprint server for biology
|February 24, 2025
概括
在克拉特林介导的内细胞分裂过程中,Epsin1充当货物传感器. 它只在无处不在的货物存在时稳定启动蛋白网络,确保有效的蛋白质和脂质内部化.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 克拉特林介导的内细胞分裂 (CME) 对于细胞过程至关重要,如营养吸收和信号传递.
- 一个动态的,类似液体的启动蛋白质网络催化了克拉斯林涂层囊泡组合.
- 这个网络的调节是产生功能性,装载载荷囊的关键.
研究的目的:
- 调查Epsin1在CME期间调节启动蛋白网络组装中的作用.
- 阐明Epsin1控制囊泡形成中的货物选择的机制.
- 了解分子相互作用如何控制液态蛋白质网络的稳定性.
主要方法:
- 在体外结合测试以研究蛋白质相互作用.
- 在哺乳动物细胞中进行细胞实验,以评估内细胞动态和连接体吸收.
- 基因操纵 (去除Epsin1和ubiquitin) 来观察救生效应.
主要成果:
- 埃普辛1在无乌比基的情况下破坏了启动蛋白凝结的稳定性,但在多比基的存在下稳定了它.
- 素1和乌比奎丁对于正常的内细胞动力学和细胞中连接体的吸收至关重要.
- 同时去除Epsin1和ubiquitin可以挽救内细胞缺陷,但会损害货物的选择性.
结论:
- Epsin1作为依赖货物的检查点,只有在无处不在的货物存在时,才会稳定发起网络.
- 这种机制确保了特定货物的有效纳入克拉特林涂层囊泡.
- 这些发现突出了平衡的吸引力和排斥力在控制细胞功能的动态蛋白质网络中的作用.
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