微管子加终跟踪蛋白直接从细胞内部准隙连接处,以粘附连接处
Robin M Shaw1, Alex J Fay, Manojkumar A Puthenveedu
1Cardiovascular Research Institute, Department of Medicine, University of California, San Francisco, CA 94143, USA.
Cell
|February 10, 2007
概括
连接素半通道通过一种由微管体依赖的途径直接准细胞-细胞结合点,涉及附着结合蛋白. 这为细胞与细胞接触时的蛋白质递送机制提供了新的见解.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 生物物理学的生物物理.
背景情况:
- 间隙连接对于细胞间通信和组织功能至关重要.
- 连接素半通道形成间隙结,但它们到细胞边界的精确传递尚未完全理解.
- 现有的模型表明,在膜输送后会发生横向扩散.
研究的目的:
- 为了研究连接素半导体通道到细胞-细胞结合的直接准机制.
- 阐明微管和相关蛋白质在这个过程中的作用.
- 挑战目前普遍存在的空隙结形成模型.
主要方法:
- 活细胞显微镜技术包括光漂白后光恢复 (FRAP) 和全内部反射光 (TIRF).
- 解卷显微镜用于高分辨率成像.
- siRNA敲下来评估蛋白质的功能.
主要成果:
- 证明了对细胞边界的半通道的直接向,独立于横向扩散.
- 确定了一条依赖于微管,N-cadherin,β-catenin,EB1和p150的途径.
- 显示了微管的优先连接,加上在粘附结处的末端,有助于半通道输送.
结论:
- 提出了一种直接将蛋白质输送到细胞结点的新机制.
- 突出了微管-附着结相互作用在组织间隙结形成中的作用.
- 提供了关于细胞间通信调节的新视角.
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