在细胞粘附部位激活素的结构基础
Constantina Bakolitsa1, Daniel M Cohen, Laurie A Bankston
1Program on Cell Adhesion, The Burnham Institute, 10901 North Torrey Pines Road, La Jolla, California 92037, USA.
Nature
|June 15, 2004
概括
素蛋白结构显示出细胞粘附调节所必需的一种自身抑制的构造. 它的激活途径确保了细胞结点的精确功能,将细胞骨动力学与粘附分子联系起来.
科学领域:
- 分子和细胞生物学分子和细胞生物学
- 结构生物学 结构生物学
- 生物物理学的生物物理.
背景情况:
- 文库林是一种关键的细胞内蛋白质,调节细胞粘附和迁移.
- 它在将actin细胞骨架连接到细胞粘附复合体方面发挥着至关重要的作用.
- 文库林在细胞质中存在于自抑制状态.
研究的目的:
- 为了确定全长素分子的晶体结构.
- 为了阐明文库林自身抑制和激活的机制.
- 了解素是如何调节细胞结点上的蛋白质与蛋白质相互作用的.
主要方法:
- 全长素 (1,066个氨基酸) 的X射线晶体学.
- 蛋白质域相互作用和形状变化的分析.
- 温林域的热力学和结构链接研究.
主要成果:
- 晶体结构显示出一个五域自抑制的形状.
- 文库林头部域类似于子,持有碳氧终端尾部域.
- 连接因子的结合受到固体和体的调节;域形状变化是相关的.
结论:
- 组合激活途径确保素仅在粘附部位激活.
- 素激活需要在细胞结点同时结合多个合作伙伴.
- 结构洞察力解释了素在将F-actin连接到cadherin和integrin分子中的作用.
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