概括
研究人员分离了特定的牛脑涂层囊泡,载有突触囊泡蛋白质. 这种功能性隔离揭示了两种新的涂层囊泡聚,进步了我们对细胞运输机制的理解.
科学领域:
- 细胞生物学 细胞生物学
- 神经科学是一个神经科学.
- 蛋白质生物化学 蛋白质生物化学
背景情况:
- 涂层囊泡对于细胞内运输至关重要,从历史上看,它们是通过结构而不是功能来净化的.
- 突触囊泡膜蛋白在神经传递中起着关键作用.
研究的目的:
- 为了隔离和表征牛脑涂层囊泡的功能子群.
- 为了识别与独特的涂层囊泡货物相关的特定蛋白质标记物.
主要方法:
- 从牛大脑中净化涂层囊泡.
- 开发一种使用单克隆抗体的免疫吸附技术.
- 通过凝电泳,通过隔离的囊泡子群的多组合的表征.
主要成果:
- 成功分离了基于特定的突触囊泡膜聚酸的涂层囊泡的两个亚群 (Mr = 95,000和65,000).
- 确定了两种新型涂层囊泡多 (Mr = 38,000和29,000),只存在于货物特定的子群体中.
- 证实单克隆抗体可以通过克拉特林层准细胞质域.
结论:
- 涂层囊泡子群可以根据其特定的膜蛋白含量进行功能隔离.
- 新型多的存在表明这些亚群在突触囊泡贩运中具有特殊作用.
- 这项工作提供了涂层囊泡的功能分成方法,并确定了囊泡运输中的新蛋白质参与者.
相关概念视频
Overview of Secretory Vesicles
Secretory vesicles, also known as dense core vesicles (DCVs), are membrane-bound vesicles that transport secretory proteins, such as hormones or neurotransmitters. Regulated secretory vesicles transport proteins from the trans-Golgi network to the exterior of the cell. Proteins present in regulated secretory vesicles are required to be rapidly exocytosed in large amounts upon a specific stimulus.
Various proteins regulate the aggregation of molecules inside the secretory vesicles. Chromogranins...
Various proteins regulate the aggregation of molecules inside the secretory vesicles. Chromogranins...
Fusion of Secretory Vesicles with the Plasma Membrane
Proteins and neurotransmitters in secretory vesicles can be released from a cell upon vesicle docking, priming, and fusion with the plasma membrane. Vesicles are docked and primed in preparation for the quick exocytosis of their contents in response to a stimulus. The fusion process is mainly carried out by a SNAP Receptor or SNARE complex, consisting of synaptobrevin, syntaxin-1, and SNAP-25.
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
Membrane-enclosed structures called vesicles transport proteins and lipids across the cell. The vesicles derive their cargo from the plasma membrane, Golgi, ER, or endosome. Coated vesicles are spherical, protein-coated carriers with a 50–100 nm diameter that mediate bidirectional transport between the ER and the Golgi. The distribution of proteins between the ER and Golgi complex is dynamic and is maintained by different coated vesicles. Their formation is driven by the assembly of different...
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.
Coat assembly depends on the local availability of phosphatidylinositol phosphates or PIPs and GTP-binding proteins. Adaptor proteins, which link the coat proteins to the membrane, bind to these PIPs and play a crucial role in controlling...
Coat assembly depends on the local availability of phosphatidylinositol phosphates or PIPs and GTP-binding proteins. Adaptor proteins, which link the coat proteins to the membrane, bind to these PIPs and play a crucial role in controlling...
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...
With the help of motor proteins such...
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...


