title: Caveolin-1 regulates matrix metalloproteinases-1 induction and CD147/EMMPRIN cell surface clustering.
abstract: CD147, a regulator of matrix metalloproteinase (MMP) production, showed highly specific association with caveolin-1 on the surface of multiple cell types. CD147-caveolin-1 complex formation was temperature and cholesterol dependent, reminiscent of associations seen within caveolae/lipid rafts. However, the subset of caveolin-1 associated with CD147 appeared exclusively within intermediate density sucrose gradient fractions, rather than in the low density fractions containing the bulk of caveolin-1. Mutagenesis experiments revealed that CD147 Ig domain 2 was required for caveolin-1 association. In contrast to CD147-caveolin-1 complexes, CD147-alpha(3) integrin association was not disrupted upon cholesterol depletion, occurred in high density sucrose fractions, and did not involve CD147 Ig domain 2. Overexpression of caveolin-1 caused a specific decrease in clustering of cell surface CD147, as detected by "cluster specific" mAb M6/13. Conversely, a mutant CD147 deficient in caveolin-1 association showed enhanced spontaneous cell surface clustering (detected by mAb M6/13), and did not show decreased clustering in response to caveolin-1 overexpression. Furthermore, the same CD147 mutant yielded an elevated induction of MMP-1. In conclusion, caveolin-1 associates with CD147, in a complex distinct from CD147-alpha(3) integrin complexes, thereby diminishing both CD147 clustering and CD147-dependent MMP-1-inducing activity.
authors.affiliation: Dana-Farber Cancer Institute and Department of Pathology, Harvard Medical School, Boston, Massachusetts 02115, USA.
authors.forename: Wei
authors.initials: W
authors.lastname: Tang
authors.forename: Martin E
authors.initials: ME
authors.lastname: Hemler
mesh_terms: D015703:Antigens, CD; D000951:Antigens, Neoplasm; D000954:Antigens, Surface; D030161:Avian Proteins; D051926:Basigin; D001798:Blood Proteins; D051242:Caveolin 1; D022461:Caveolins / Q000502:physiology*; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism; D004790:Enzyme Induction; D006801:Humans; D020781:Matrix Metalloproteinase 1 / Q000096:biosynthesis*; D008562:Membrane Glycoproteins / Q000378:metabolism*
chemical_list: D015703:Antigens, CD; D000951:Antigens, Neoplasm; D000954:Antigens, Surface; D030161:Avian Proteins; C497886:BSG protein, human; D001798:Blood Proteins; C102624:Bsg protein, Gallus gallus; C079432:Bsg protein, rat; C495540:CAV1 protein, human; D051242:Caveolin 1; D022461:Caveolins; D008562:Membrane Glycoproteins; D051926:Basigin; D020781:Matrix Metalloproteinase 1