INTEGRIN RECEPTORS ON AORTIC SMOOTH-MUSCLE CELLS MEDIATE ADHESION TO FIBRONECTIN, LAMININ, AND COLLAGEN
INTEGRIN RECEPTORS ON AORTIC SMOOTH-MUSCLE CELLS MEDIATE ADHESION TO FIBRONECTIN, LAMININ, AND COLLAGEN
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DOI：
10.1161/01.res.67.1.175
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发表时间：
1990-07-01
影响因子：
20.1
通讯作者：
KRAMER, RH
中科院分区：
文献类型：
--
作者：
CLYMAN, RI;MCDONALD, KA;KRAMER, RH
血管平滑肌细胞上的细胞外基质受体有助于在收缩期间锚定细胞并促进血管损伤后的细胞迁移。我们发现，大鼠主动脉平滑肌细胞附着在纤维连接蛋白，层粘连蛋白和胶原蛋白I型和IV型的表面。细胞与这些底物的附着似乎由细胞外基质受体的β 1整联蛋白家族的成员介导。针对β 1亚基的抗体不仅证实了粘着斑中整联蛋白复合物的存在，而且还阻断了细胞对不同底物的粘着。配体亲和层析和十二烷基硫酸钠-聚丙烯酰胺凝胶电泳分离出一系列受体复合物，其被β 1整联蛋白受体的抗血清识别。每种受体似乎是异二聚体，其中几种α-受体之一是异二聚体。亚基共享共同的120-kDa（非还原的）β 1亚基蛋白。大鼠主动脉平滑肌细胞具有一个α。亚基（150 kDa非还原，140 kDa还原），仅与纤连蛋白结合。有第二个。阿尔法。亚基（150 kDa非还原，160 kDa还原），仅与I型胶原蛋白结合。此外，还有第三个α。亚基（185 kDa非还原的，200 kDa还原的），其是混杂的并且结合至I型和IV型胶原以及层粘连蛋白;亚基与胶原蛋白的结合比与层粘连蛋白的结合更有效。因此，平滑肌细胞表达多种具有不同配体特异性的整合素受体，其似乎介导细胞与细胞外基质的相互作用。
Extracellular matrix receptors on vascular smooth muscle cells help in anchoring the cells during contraction and in promoting cellular migration after vessel injury. We found that rat aortic smooth muscle cells attach to surfaces coated with fibronectin, laminin, and collagen types I and IV. Cell attachment to these substrates appears to be mediated by members of the .beta.1 integrin family of extracellular matrix receptors. Antibodies to the .beta.1 subunit not only demonstrated the presence of integrin complexes in focal adhesion plaques but also blocked cell adhesion to the different substrates. Ligand-affinity chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis isolated a series of receptor complexes that were recognized by antiseria to .beta.1 integrin receptors. Each of the receptors appeared to be a heterodimer in which one of several .alpha. subunits shared a common 120-kDa (nonreduced) .beta.1 subunit protein. The rat aortic smooth muscle cells had one .alpha. subunit (150 kDa nonreduced, 140 kDa reduced) that bound exclusively to fibronectin. There was a second .alpha. subunit (150 kDa nonreduced, 160 kDa reduced) that bound exclusively to collagen type I. In addition, there was a third .alpha. subunit (185 kDa nonreduced, 200 kDa reduced) that was promiscuous and bound to collagen types I and IV as well as to laminin; the 185-kDa .alpha. subunit appeared to bind to collagen more efficiently than it did to laminin. Thus, smooth muscle cells express multiple integrin receptors with different ligand specificities that appear to mediate cell interactions with the extracellular matrix.