在MDCK细胞中LDL受体的基侧分类:细胞质域含有两种依赖于氨酸的向决定因素
K Matter1, W Hunziker, I Mellman
1Department of Cell Biology, Yale University School of Medicine, New Haven, Connecticut 06510.
Cell
|November 27, 1992
概括
研究人员发现了两种不同的信号,这些信号将膜蛋白引导到MDCK细胞的底侧血膜. 这些依赖于氨酸的信号在功能上是多余的,这表明细胞内事件有一个共同的分类机制.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 膜蛋白贩运 人口贩运 膜蛋白贩运
背景情况:
- 在MDCK细胞中膜蛋白的基底侧等离子膜向需要特定的细胞质域决定因素.
- 这些决定因素通常与克拉斯林涂层坑位定位的信号有关,但这并不总是如此,如人类的LDL受体所见.
研究的目的:
- 识别和描述负责人类LDL受体的底侧向的特定信号.
- 调查这些基底侧排序决定因素的功能冗余性和特征.
主要方法:
- 在MDCK细胞中突变和仿真人类LDL受体的表达.
- 分析蛋白质局部化和贩运途径.
主要成果:
- 确定了两个独立的信号,足以进行底侧准.
- 这两种信号都含有关键的氨酸残留物,但效率不同.
- 一个信号与克拉涂层坑域不同,但与其直线;第二个信号位于C端区域,不介导内细胞分裂.
结论:
- 膜蛋白可以拥有功能冗余的信号,用于底侧传输.
- 含氨酸的图案可以作为多个细胞内分类事件的共同特征,包括基底侧向和内细胞分裂.
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