用于非膀式贩运陶胺的分子机器
Kentaro Hanada1, Keigo Kumagai, Satoshi Yasuda
1Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, 1-23-1, Toyama, Shinjuku-ku, Tokyo 162-8640, Japan. hanak@nih.go.jp
Nature
|December 20, 2003
概括
CERT蛋白对于将胺脂从内质网膜运送到戈尔吉器官至关重要. 在CERT中存在的缺陷会损害这种必不可少的膜生物发生路径.
科学领域:
- 细胞生物学 细胞生物学
- 生物化学 生化学
- 分子生物学分子生物学
背景情况:
- 脂质合成和分类对于创建新的细胞膜至关重要.
- 膜脂质,特别是胺的运输机制尚不清楚.
- 在内质网膜中合成的胺必须到达戈尔吉,以产生基肌蛋白.
研究的目的:
- 为了确定负责陶胺运输到戈尔吉的蛋白质.
- 为了研究这种陶胺运输蛋白的功能和机制.
- 了解特定的哺乳动物突变细胞系 (LY-A) 具有受损胺转运的分子基础.
主要方法:
- 对LY-A突变细胞系的基因分析.
- 蛋白质识别和CERT (陶运输蛋白) 的表征.
- 通过使用纯化的CERT进行体外脂质转移试验.
- 对CERT突变及其对戈尔吉向定位的影响的功能分析.
主要成果:
- 鉴定出CERT蛋白是LY-A细胞中缺陷的因素.
- CERT 具有一种酸-4-单酸结合 (PtdIns4P) 域和一种脂质转移域.
- 脂质转移域在体外从膜中提取胺.
- LY-A细胞中的突变破坏了CERT的PtdIns4P结合和Golgi向能力.
结论:
- 在CERT中介于胺的非囊膜细胞内贩运.
- CERT的功能对于将陶胺运送到戈尔吉装置至关重要.
- CERT的PtdIns4P结合活动对其Golgi定位和功能至关重要.
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