Bertocchi Cristina, Wang Yilin, Ravasio Andrea, Hara Yusuke, Wu Yao, Sailov Talgat, Baird Michelle A, Davidson Michael W, Zaidel-Bar Ronen, Toyama Yusuke, Ladoux Benoit, Mege Rene-Marc, Kanchanawong Pakorn
Mechanobiology Institute, Singapore 117411, Republic of Singapore.
National High Magnetic Field Laboratory, The Florida State University, Tallahassee, Florida 32310, USA.
Nat Cell Biol. 2017 Jan;19(1):28-37. doi: 10.1038/ncb3456. Epub 2016 Dec 19.
Multicellularity in animals requires dynamic maintenance of cell-cell contacts. Intercellularly ligated cadherins recruit numerous proteins to form supramolecular complexes that connect with the actin cytoskeleton and support force transmission. However, the molecular organization within such structures remains unknown. Here we mapped protein organization in cadherin-based adhesions by super-resolution microscopy, revealing a multi-compartment nanoscale architecture, with the plasma-membrane-proximal cadherin-catenin compartment segregated from the actin cytoskeletal compartment, bridged by an interface zone containing vinculin. Vinculin position is determined by α-catenin, and following activation, vinculin can extend ∼30 nm to bridge the cadherin-catenin and actin compartments, while modulating the nanoscale positions of the actin regulators zyxin and VASP. Vinculin conformational activation requires tension and tyrosine phosphorylation, regulated by Abl kinase and PTP1B phosphatase. Such modular architecture provides a structural framework for mechanical and biochemical signal integration by vinculin, which may differentially engage cadherin-catenin complexes with the actomyosin machinery to regulate cell adhesions.
动物中的多细胞性需要动态维持细胞间接触。细胞间连接的钙黏着蛋白招募众多蛋白质形成超分子复合物,这些复合物与肌动蛋白细胞骨架相连并支持力的传递。然而,此类结构中的分子组织仍然未知。在这里,我们通过超分辨率显微镜绘制了基于钙黏着蛋白的黏附中的蛋白质组织图,揭示了一种多隔室纳米级结构,其中靠近质膜的钙黏着蛋白 - 连环蛋白隔室与肌动蛋白细胞骨架隔室分离,由包含纽蛋白的界面区桥接。纽蛋白的位置由α - 连环蛋白决定,激活后,纽蛋白可延伸约30纳米以桥接钙黏着蛋白 - 连环蛋白和肌动蛋白隔室,同时调节肌动蛋白调节因子斑联蛋白和血管舒张刺激蛋白的纳米级位置。纽蛋白的构象激活需要张力和酪氨酸磷酸化,由Abl激酶和PTP1B磷酸酶调节。这种模块化结构为纽蛋白进行机械和生化信号整合提供了一个结构框架,纽蛋白可能以不同方式使钙黏着蛋白 - 连环蛋白复合物与肌动球蛋白机制结合,从而调节细胞黏附。