整体血通道蛋白的多子单元组合,间隙结连xin43,发生在退出ER后
1Department of Cell Biology, Harvard Medical School, Boston, Massachusetts 02115.
Cell
|September 24, 1993
概括
连接素43 (Cx43) 单体在细胞内形成通道,特别是在跨高尔基网络中. 这种组装过程需要从内分泌网膜到戈尔吉的运输,与其他膜蛋白不同.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 连xin43 (Cx43) 是一个关键的整体血蛋白,负责形成脊椎动物细胞的间隙结.
- 间隙结通过允许小分子和离子通过,促进了细胞间直接的细胞间通信.
研究的目的:
- 研究间隙连接组装的初始步骤:Cx43单体的寡合化成连接道.
- 确定Cx43连接子组件的细胞内位置和运输要求.
主要方法:
- 糖梯度分化以分离蛋白质复合体.
- 化学交叉链接用于识别相互作用的Cx43单体.
- 通过使用特定的试剂和温度转移,抑制内质网膜 (ER) 到戈尔吉的传输.
- 对具有分泌缺陷的CHO细胞突变的分析.
主要成果:
- 通过抑制ER-to-Golgi运输,Cx43连接组件被特别阻止.
- 像碳酸m-chloro-phenylhydrazone和brefeldin A这样的抑制剂,以及低温,阻止了Cx43的寡合化.
- 连接组件是局部化的细胞内,主要是在跨戈尔吉网络.
- 这种组装途径不同于其他整体血蛋白的组装途径.
结论:
- Cx43间隙连接组件遵循一个后ER路径,发生在跨戈尔吉网络.
- 细胞内运输和Cx43的寡合化密切相关.
- 这项研究揭示了整体膜蛋白组装的独特机制及其与细胞内贩运的关系.
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