Gálvez Beatriz G, Matías-Román Salomón, Yáñez-Mó María, Sánchez-Madrid Francisco, Arroyo Alicia G
Departamento de Inmunología, Hospital de la Princesa, C/Diego de León 62, 28006 Madrid, Spain.
J Cell Biol. 2002 Nov 11;159(3):509-21. doi: 10.1083/jcb.200205026.
Regulation of membrane-type 1 matrix metalloproteinase (MT1-MMP) by different extracellular matrices (ECMs) on human endothelial cells (ECs) has been investigated. First, MT1-MMP is found at the intercellular contacts of confluent ECs grown on beta1 integrin-dependent matrix such as type 1 collagen (COL I), fibronectin (FN), or fibrinogen (FG), but not on gelatin (GEL) or vitronectin (VN). The novel localization of MT1-MMP at cell-cell contacts is assessed by confocal videomicroscopy of MT1-MMP-GFP-transfected ECs. Moreover, MT1-MMP colocalizes with beta1 integrins at the intercellular contacts, whereas it is preferentially found with alphavbeta3 integrin at motility-associated structures on migrating ECs. In addition, clustered integrins recruit MT1-MMP and neutralizing anti-beta1 or anti-alphav integrin mAb displace MT1-MMP from its specific sites, pointing to a biochemical association that is finally demonstrated by coimmunoprecipitation assays. On the other hand, COL I, FN, or FG up-regulate cell surface MT1-MMP on confluent ECs by an impairment of its internalization, whereas expression and internalization are not modified on GEL or VN. In addition, MT1-MMP activity is diminished in confluent ECs on COL I, FN, or FG. Finally, MT1-MMP participates and cooperates with beta1 and alphavbeta3 integrins in the migration of ECs on different ECM. These data show a novel mechanism by which ECM regulates MT1-MMP association with beta1 or alphavbeta3 integrins at distinct cellular compartments, thus modulating its internalization, activity, and function on human ECs.
研究了不同细胞外基质（ECM）对人内皮细胞（EC）上膜型1基质金属蛋白酶（MT1-MMP）的调节作用。首先，在依赖β1整合素的基质（如I型胶原（COL I）、纤连蛋白（FN）或纤维蛋白原（FG））上生长的汇合EC的细胞间接触处发现了MT1-MMP，而在明胶（GEL）或玻连蛋白（VN）上则未发现。通过对MT1-MMP-GFP转染的EC进行共聚焦视频显微镜观察，评估了MT1-MMP在细胞-细胞接触处的新定位。此外，MT1-MMP在细胞间接触处与β1整合素共定位，而在迁移EC的运动相关结构上则优先与αvβ3整合素一起被发现。另外，聚集的整合素募集MT1-MMP，中和性抗β1或抗αv整合素单克隆抗体将MT1-MMP从其特定位点置换，这表明了一种生化关联，最终通过共免疫沉淀试验得以证实。另一方面，COL I、FN或FG通过损害其内化作用上调汇合EC上的细胞表面MT1-MMP，而在GEL或VN上其表达和内化未被改变。此外，在COL I、FN或FG上的汇合EC中，MT1-MMP活性降低。最后，MT1-MMP在不同ECM上EC的迁移过程中与β1和αvβ3整合素参与并协同作用。这些数据显示了一种新机制，通过该机制ECM在不同细胞区室调节MT1-MMP与β1或αvβ3整合素的关联，从而调节其在内皮细胞上的内化、活性和功能。
