在生物合成膜运输过程中,β-COP是必不可少的,它从内质网膜到Golgi复合体在生物体内是必不可少的
R Pepperkok1, J Scheel, H Horstmann
1European Molecular Biology Laboratory, Heidelberg, Federal Republic of Germany.
Cell
|July 16, 1993
概括
阻断β-COP,一种外套蛋白质,抑制了哺乳动物细胞中病毒葡萄糖蛋白和内源蛋白的运输. 这证明了β-COP.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 贩卖蛋白质 贩卖蛋白质 是一个问题.
背景情况:
- 非克拉特林涂层的囊泡对于细胞内运输至关重要.
- β-COP (外套蛋白β) 是这些囊泡的一个组成部分.
- 了解β-COP的功能是解读膜交通通道的关键.
研究的目的:
- 为了研究β-COP在生物合成膜流通中的体内作用.
- 为了确定受β-COP抑制影响的蛋白质运输的特定阶段.
主要方法:
- 在哺乳动物细胞中微注射针对β-COP的抗体.
- 使用温度敏感囊泡性口腔炎病毒糖蛋白 (ts-O45-G) 作为模型货物.
- 通过温度变化和细胞表面运输试验,分析蛋白质的运输和修饰 (例如,内葡萄糖酶H抗性).
主要成果:
- 对β-COP的抗体阻断了TS-O45-G的传输到细胞表面.
- 抑制发生在内分泌网膜 (ER) 和中间区间阶段,但没有发生在跨戈尔吉网络.
- 在ER-Golgi中间管状结构中积累的Ts-O45-G.
- 内源蛋白质的分泌和 cathepsin D 成熟也受到影响.
结论:
- β-COP在哺乳动物细胞生物合成膜流通中发挥着关键作用.
- 抑制β-COP会在早期到中间阶段破坏蛋白质的运输.
- 这些发现提供了体内证据,证明β-COP在囊泡介导的运输中起着重要的作用.
相关概念视频
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ER Retrieval Pathway
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Cotranslational Protein Translocation
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Sec61 channel partners for cotranslational translocation
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Sec61 channel partners for cotranslational translocation
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Post-translational Translocation of Proteins to the RER
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Targeting proteins to the ER
Hsp40 and Hsp70 chaperone molecules bind the translated proteins in the cytosol to prevent their folding. The chaperone binding helps to keep the signal...
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While it is unclear how molecules move between adjacent Golgi cisternae, it is apparent that the molecules move from cis- cisterna, the entry face, to the trans- cisterna, the exit face. Experiments initially suggested vesicles that bud from one cisterna and fuse with the next cisterna to transport proteins between the cisternae. This vesicular transport model describes the Golgi apparatus as a relatively static structure with a unique enzyme composition in each cisterna. Molecules are...


