The distribution of distinct integrins in focal contacts is determined by the substratum composition.
The distribution of distinct integrins in focal contacts is determined by the substratum composition.
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DOI：
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发表时间：
1989
影响因子：
4
通讯作者：
Karl R. Fath;C.-J. S. Edgell;Keith Burridge
中科院分区：
文献类型：
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作者：
Karl R. Fath;C.-J. S. Edgell;Keith Burridge
两个整合素，纤连蛋白受体和玻连蛋白受体的分布，已被探讨在内皮细胞衍生的细胞系接种到各种基质。在纤连蛋白基质上，在血清的存在下，这些细胞产生含有纤连蛋白受体的焦点接触，而玻连蛋白受体弥散分布在细胞表面上。相反，接种在玻连蛋白包被的盖玻片上的细胞仅集中在焦点接触内的玻连蛋白受体。玻连蛋白受体在病灶接触内的积累也发生在细胞接种在未涂布的盖玻片上但存在血清时。因此，我们得出结论，在正常培养条件下（即在含血清的培养基中），玻连蛋白受体是参与基质粘附的整合素的主要形式。这一结论得到了实验的支持，在该实验中，细胞在血清存在下在纤连蛋白包被的盖玻片上培养。最初，这些细胞产生仅含有纤连蛋白受体的局灶性接触。然而，在几个小时内，含有纤连蛋白受体的焦点接触逐渐被表达玻连蛋白受体的焦点接触取代。培养约12小时后，大多数细胞含有仅表达玻连蛋白受体的病灶接触。含有纤连蛋白或玻连蛋白受体的局灶性接触都与应力纤维的末端相关，并含有蛋白质塔林蛋白和黏着斑蛋白。这些观察结果使我们提出，细胞不区分这些不同的整合素组装时，在细胞质面的焦点接触的细胞骨架成分。
The distribution of two integrins, the fibronectin receptor and the vitronectin receptor, has been explored in an endothelium-derived cell line plated onto various substrata. On a fibronectin substratum, in the presence of serum, these cells develop focal contacts that contain the fibronectin receptor, whereas the vitronectin receptor is diffusely distributed over the cell surface. Conversely, cells plated onto vitronectin-coated coverslips concentrate only the vitronectin receptor within focal contacts. The accumulation of the vitronectin receptor within focal contacts also occurs when the cells are plated on uncoated coverslips but in the presence of serum. Therefore, we conclude that under normal culture conditions (i.e. in serum-containing media), the vitronectin receptor is the predominant form of integrin involved in substratum adhesion. This conclusion is supported by experiments in which cells were cultured on fibronectin-coated coverslips in the presence of serum. Initially these cells developed focal contacts containing only the fibronectin receptor. Within several hours, however, there was a progressive replacement of focal contacts containing the fibronectin receptor by focal contacts expressing the vitronectin receptor. After approximately 12 h in culture, most cells contained focal contacts expressing only the vitronectin receptor. Focal contacts containing either the fibronectin or vitronectin receptor were both associated with the termini of stress fibres and contained the proteins talin and vinculin. These observations lead us to propose that the cell does not discriminate between these different integrins when assembling the cytoskeletal components at the cytoplasmic face of focal contacts.