定向性actin聚合是表皮细胞-细胞粘附的驱动力
1Department of Molecular Genetics and Cell Biology, Howard Hughes Medical Institute, The University of Chicago, Illinois 60637, USA.
Cell
|February 5, 2000
概括
皮质细胞使用激活的filopodia嵌入到邻居,形成粘附拉链. 这个过程需要α-catenin和VASP/Mena来进行actin重组以密封细胞边界.
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:
- 表皮细胞通过细胞间粘附形成组织.
- 卡德林介导的粘附对于组织完整性至关重要.
- 细胞-细胞粘附动态的精确机制仍在被阐明.
研究的目的:
- 为了研究和乙烯酸聚合在素介导细胞间粘附中的新型作用.
- 阐明涉及密封表皮细胞边界的分子参与者和机制.
主要方法:
- 活细胞成像,观察类动物的动态和细胞边界密封.
- 在皮细胞中对α-catenin和VASP/Mena功能进行基因操纵.
- 免疫光显微镜可视化蛋白质定位和actin组织.
主要成果:
- 刺激了穿透邻近细胞的filopodia,在尖端聚集了E-cadherin.
- 形成一个两行拉链的puncta,通过desmosomes紧.
- 阿尔法-素,素,齐辛,VASP和Mena被招募到粘附拉链上.
- 动蛋白重组和聚合对于融合点和密封细胞边界至关重要.
- 破坏α-catenin或VASP/Mena功能会阻止膜密封.
结论:
- 揭示了细胞间粘附的动态机制,包括激活的filopodia透和VASP/Mena依赖的actin重组.
- α-catenin和VASP/Mena对于表皮细胞边界的基于actin的密封是至关重要的.
- 这项研究揭示了建立和维护上皮组织完整性的新途径.
相关概念视频
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