Binding and processing of multimeric vitronectin by vascular endothelial cellsW Volker, S Hess, P Vischer and KT Preissner Institute of Arteriosclerosis Research, University of Munster, Germany. The multifunctional adhesive glycoprotein vitronectin (VN) undergoes a unique conformational transition from the plasma form into a multimeric form that represents the reactive heparin-binding form. In this study we investigated the interaction of multimeric vitronectin (VNmult) or VN-gold conjugates (which are equivalent in biochemical properties) with confluent and subconfluent monolayers of porcine endothelial cells. Time-dependent direct binding of radiolabeled VNmult to the luminal face of endothelial cells at 37 degrees C was observed which was competed by heparin, whereas plasma VN showed hardly any binding. At 4 degrees C binding of VNmult remained cell-associated, whereas after 6 hr at 37 degrees C a major portion of the ligand was translocated through cells and was associated with the subcellular matrix. Cytochemical studies with VN-gold conjugates were performed to demonstrate uptake of VNmult. At 4 degrees C only surface decoration of cells with gold label was seen, which was totally reversible in the presence of heparin. Subsequent incubation for various time intervals at 37 degrees C revealed disappearance of gold label from the surface and accumulation of conjugates in a perinuclear distribution inside the cells as judged both by electron microscopy and after silver enhancement by light microscopy. Cross-sections of endothelial cells demonstrated the inclusion of VN-gold conjugates in coated pits, endosomes, and in lysosomal compartments close to the nucleus. Within 2- 6 hr a portion of VN-gold conjugates had accumulated with proteoglycans at the matrix face. These data provide strong evidence for specific routing of a portion of VNmult from the circulation into extravascular spaces, where the protein is believed to fulfill major adhesive and regulatory functions particularly as co-factor in plasminogen activation and immune defense.
Volume 41,
Issue 12,
pp. 1823-1832,
12/01/1993
|
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
![]() |
D. H. Anderson, G. S. Hageman, R. F. Mullins, M. Neitz, J. Neitz, S. Ozaki, K. T. Preissner, and L. V. Johnson Vitronectin Gene Expression in the Adult Human Retina Invest. Ophthalmol. Vis. Sci., December 1, 1999; 40(13): 3305 - 3315. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. C. Hocking, J. Sottile, T. Reho, R. Fassler, and P. J. McKeown-Longo Inhibition of Fibronectin Matrix Assembly by the Heparin-binding Domain of Vitronectin J. Biol. Chem., September 17, 1999; 274(38): 27257 - 27264. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. S. HAGEMAN, R. F. MULLINS, S. R. RUSSELL, L. V. JOHNSON, and D. H. ANDERSON Vitronectin is a constituent of ocular drusen and the vitronectin gene is expressed in human retinal pigmented epithelial cells FASEB J, March 1, 1999; 13(3): 477 - 484. [Abstract] [Full Text] |
||||
![]() |
D. Seiffert and D. J. Loskutoff Type 1Plasminogen Activator Inhibitor Induces Multimerization of Plasma Vitronectin. A SUGGESTED MECHANISM FOR THE GENERATION OF THE TISSUE FORM OF VITRONECTIN IN VIVO J. Biol. Chem., November 22, 1996; 271(47): 29644 - 29651. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. S. Panetti, S. A. Wilcox, C. Horzempa, and P. J. McKeown-Longo alpha(v)beta(5)Integrin Receptor-mediated Endocytosis of Vitronectin Is Protein Kinase C-dependent J. Biol. Chem., August 4, 1995; 270(31): 18593 - 18597. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Bhattacharya, C. Fu, J. Bhattacharya, and S. Greenberg Soluble Ligands of the [IMAGE][IMAGE][IMAGE][IMAGE] Integrin Mediate Enhanced Tyrosine Phosphorylation of Multiple Proteins in Adherent Bovine Pulmonary Artery Endothelial Cells J. Biol. Chem., July 14, 1995; 270(28): 16781 - 16787. [Abstract] [Full Text] [PDF] |
||||
| Guidelines | Subscriptions | About | exPRESS - Current - Archive | Business Information | Contact |