概括
研究人员在体外复制了涂层坑组件,揭示了膜上的特定结合点和关键蛋白质的招募. 这个过程不依赖ATP,但对温度变化敏感.
科学领域:
- 细胞生物学 细胞生物学
- 细胞内核的分子机制 细胞内核的分子机制
背景情况:
- 受体介导的内细胞分裂包括涂层,形成涂层囊泡.
- 克拉和相关蛋白质分离并重塑细胞表面的涂层坑.
研究的目的:
- 阐明调控涂层坑功能的分子机制.
- 为了在体外复制涂层坑循环的组装阶段.
主要方法:
- 用细胞细胞质化净化膜 (经过处理以去除内源性涂层坑)
- 在实验室中观察膜上涂层坑的组合.
主要成果:
- 涂层坑组件在体外模仿完整的细胞形成.
- 膜具有有限的,高亲和度的克拉林结合点.
- 组装半程时间为5分钟,在4°C和37°C的温度下.
- 在组装过程中招募了180,110和36kDa的蛋白质.
- 组装是独立于ATP的,但ATP会触发温度依赖的涂层坑损失.
结论:
- 实验室系统有效地模拟了涂层坑组件.
- 特定的分子参与者和条件决定了涂层坑的形成和动态.
相关概念视频
Fusion of Secretory Vesicles with the Plasma Membrane
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In 1993, Jim Rothman proposed that the antiparallel pairing of vesicular and transmembrane SNAREs, or...
In 1993, Jim Rothman proposed that the antiparallel pairing of vesicular and transmembrane SNAREs, or...
COP Coated Vesicles
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Coat Assembly and GTPases
Vesicles incorporate different coat protein subunits in different cell locations, which changes the properties of the coat, such as the shape and geometry of the transport vesicles. Thus, vesicle coat proteins also play a significant role in cargo selection.
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Vesicular Tubular Clusters
After budding out from the ER membrane, some COPII vesicles lose their coat and fuse with one another to form larger vesicles and interconnected tubules called vesicular tubular clusters or VTCs. These clusters constitute a compartment at the ER-Golgi interface known as ERGIC (Endoplasmic Reticulum Golgi Intermediate Compartment). The ERGIC is a mobile membrane-bound cargo transport system that sorts proteins secreted from ER and delivers them to the Golgi.
With the help of motor proteins such...
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Clathrin Coated Vesicles
Clathrin-coated vesicles use endocytosis to transport receptors and lysosomal hydrolases from the Golgi to the lysosome in the late secretory pathway. Clathrin-mediated endocytosis was the first described endocytic process, and Clathrin-coated vesicles remain one of the most well-studied transport vesicles. The molecular machinery that generates clathrin-coated vesicles comprises over 50 proteins that precisely coordinate vesicle formation. Cell surface receptors concentrated in indented sites...


