Wierzbicka-Patynowski Iwona, Schwarzbauer Jean E
Department of Molecular Biology, Princeton University, Princeton, NJ 08544-1014 USA.
J Cell Sci. 2003 Aug 15;116(Pt 16):3269-76. doi: 10.1242/jcs.00670.
Cell phenotype is specified by environmental cues embedded in the architecture and composition of the extracellular matrix (ECM). Much has been learned about matrix organization and assembly through analyses of the ECM protein fibronectin (FN). FN matrix assembly is a cell-mediated process in which soluble dimeric FN is converted into a fibrillar network. Binding of cell surface integrin receptors to FN converts it to an active form, which promotes fibril formation through interactions with other cell-associated FN dimers. As FN fibrils form on the outside of the cell, cytoplasmic domains of integrin receptors organize cytoplasmic proteins into functional complexes inside. Intracellular connections to the actin cytoskeletal network and stimulation of certain key intracellular signaling pathways are essential for FN-integrin interactions and propagation of FN fibril formation. Thus, assembly of native functional ECM depends on exquisite coordination between extracellular events and intracellular pathways.
细胞表型由细胞外基质（ECM）的结构和组成中所包含的环境线索决定。通过对细胞外基质蛋白纤连蛋白（FN）的分析，人们对基质的组织和组装有了很多了解。FN基质组装是一个细胞介导的过程，其中可溶性二聚体FN被转化为纤维状网络。细胞表面整合素受体与FN结合将其转化为活性形式，通过与其他细胞相关的FN二聚体相互作用促进纤维形成。随着FN纤维在细胞外形成，整合素受体的细胞质结构域将细胞质蛋白组织成细胞内的功能复合物。与肌动蛋白细胞骨架网络的细胞内连接以及某些关键细胞内信号通路的激活对于FN-整合素相互作用和FN纤维形成的传播至关重要。因此，天然功能性ECM的组装依赖于细胞外事件和细胞内途径之间的精确协调。
