纳米级分析表明,脂质流不会驱动膜糖蛋白的运动
1Department of Cell Biology, Washington University School of Medicine, St Louis, Missouri 63110.
Nature
|July 27, 1989
概括
膜糖蛋白不跟随脂质流,但一些与细胞骨相连的蛋白质向后移动. 这些发现揭示了不同的膜蛋白动态及其与细胞结构的关系.
科学领域:
- 细胞生物学 细胞生物学
- 生物物理学的生物物理.
背景情况:
- 膜糖蛋白在细胞过程中起着至关重要的作用.
- 了解它们的运动是解读细胞功能的关键.
研究的目的:
- 在纳米尺度上分析膜糖蛋白的运动.
- 为了确定糖蛋白扩散是否受到脂质流或细胞骨相互作用的影响.
主要方法:
- 采用黄金颗粒标记,用于高分辨率追踪膜糖蛋白.
- 进行了粒子运动的纳米级分析.
主要成果:
- 自由扩散的膜糖蛋白不受大量脂质流动的影响.
- 糖蛋白的一个亚群,看似与细胞骨相关,表现出向后运动.
结论:
- 膜糖蛋白的移动性不仅仅是由脂质双层动态决定的.
- 细胞骨附着显著影响特定膜蛋白的方向运动.
相关概念视频
Membrane Fluidity
Membrane fluidity is explained by the fluid mosaic model of the cell membrane, which describes the plasma membrane structure as a mosaic of components—including phospholipids, cholesterol, proteins, and carbohydrates—that gives the membrane a fluid character.
Mosaic nature of the membrane
The mosaic characteristic of the membrane helps the plasma membrane remain fluid. The integral proteins and lipids exist as separate but loosely-attached molecules in the membrane. The membrane is a relatively...
Mosaic nature of the membrane
The mosaic characteristic of the membrane helps the plasma membrane remain fluid. The integral proteins and lipids exist as separate but loosely-attached molecules in the membrane. The membrane is a relatively...
Fluid Mosaic Model
Scientists identified the plasma membrane in the 1890s and its principal chemical components (lipids and proteins) by 1915. The model for plasma membrane structure, proposed in 1935 by Hugh Davson and James Danielli, was the first model to be widely accepted in the scientific community. The model was based on the plasma membrane's "railroad track" appearance in early electron micrographs. Davson and Danielli theorized that the plasma membrane's structure resembled a sandwich with the analogy of...
Asymmetric Lipid Bilayer
Biological membranes show uneven distribution of different types of lipids in the inner and outer layers, resulting in transverse asymmetric membranes. The treatment of the erythrocyte membrane with the enzyme phospholipase confirmed the asymmetric nature of the lipid bilayer. The enzyme hydrolyzes lipids into fatty acids and hydrophilic groups. The phospholipase acts only on the outer layer of the membrane, while the inner layer remains intact. The phospholipase treatment resulted in 80%...
Protein Diffusion in the Membrane
Proteins show rotational as well as lateral diffusion across the membrane. The lateral diffusion of proteins was confirmed through the cell fusion experiment where mouse and human cells were fused, resulting in hybrid cells. When the human and mouse cells fused, the specific membrane proteins on human and mouse cells were marked with the red and green-fluorescent markers, respectively. Initially, the red and green fluorescence was located on the respective hemisphere of the cell. As time...


