常见的信号控制了内分体中的低密度脂蛋白受体分类和MDCK细胞的戈尔吉综合体
K Matter1, J A Whitney, E M Yamamoto
1Department of Cell Biology, New Haven, Connecticut 06510.
Cell
|September 24, 1993
概括
在LDL受体细胞质域中的两个关键信号指导其在戈尔吉和内分泌体中的两极分化分类. 这确保了适当的受体循环,并防止错误分离到顶端膜.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 膜贩卖 膜贩卖 膜贩卖 膜贩卖
背景情况:
- 低密度脂蛋白受体 (LDL受体) 调解胆固醇的吸收.
- 极化分类将蛋白质引导到上皮细胞中的特定膜域.
- 了解受体贩运对于细胞功能至关重要.
研究的目的:
- 为了研究含铁素的决定因素在LDL受体的细胞质域中的作用.
- 确定这些决定因素如何影响戈尔吉和内分泌体的偏振分类.
- 阐明受体循环和细胞转移的机制.
主要方法:
- 利用麦丁 - 达比犬细胞 (MDCK),这是极化上皮细胞的模型.
- 通过对细胞质决定因素的基因操纵,研究了LDL受体的分类和贩运.
- 观察受体局部化和运动在内细胞结合后和通过戈尔吉和内基因组的运输过程中.
- 评估了brefeldin A对受体分类和运输的影响.
主要成果:
- 在LDL受体细胞质域中,两个含氨酸的决定因素独立地准了来自Golgi的基底侧膜的受体.
- 这些决定因素也控制了内体内的偏振分类.
- 远程决定因子的无活化导致基底侧循环减少,并增加了转细胞体到顶膜的转细胞体.
- 从顶端表面内化的受体通过近位决定体被运送到底侧表面.
- 布雷菲尔丁A破坏了内分体和戈尔吉的分类,但不是运输.
结论:
- 同样的信号,直接极化分类在戈尔吉也控制受体循环在内分泌体.
- 在内细胞和生物合成途径上的分类机制是相似的.
- 这些发现提供了对极化细胞中蛋白质贩运的调节的见解.
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