title: Formation of high molecular weight dermatan sulfate proteoglycan in bovine aortic endothelial cell cultures. Evidence for transglutaminase-catalyzed cross-linking to fibronectin.
abstract: Three glucuronate-rich dermatan sulfate proteoglycan (DS-PG) subclasses were isolated and previously characterized from bovine aortic endothelial cell cultures (Kinsella, M. G., and Wight, T. N. (1988) J. Biol. Chem. 263, 19222-19231). In the present study, pulse-chase experiments indicate that the DS-PG of highest apparent Mr (approximately 1 x 10(6)), denoted previously as HMW-DS, is a relatively stable component of the endothelial extracellular matrix and is formed at the expense of lower Mr DS-PG species. The formation of HMW-DS is reduced in a dose-dependent manner in the presence of dansylcadaverine, an inhibitor of transglutaminase-catalyzed protein cross-linking, but not when the activity of other cross-linking enzymes such as lysyl oxidase is inhibited. The putative DS-PG precursor to HMW-DS accumulates during inhibition of cross-linking only when lysosomal degradation is also inhibited by ammonium chloride, suggesting that the precursor is degraded rapidly in the absence of cross-linking. HMW-DS is precipitable from endothelial cell monolayer extracts with antibodies against fibronectin, a known transglutaminase substrate. Thus, we conclude that the stability of HMW-DS in the subendothelial matrix in culture depends upon the cross-linking of a low Mr DS-PG precursor to matrical protein(s), including fibronectin, resulting in the formation of a DS-PG subclass of high apparent molecular mass.
authors.affiliation: Department of Pathology, University of Washington, Seattle 98195.
authors.forename: M G
authors.initials: MG
authors.lastname: Kinsella
authors.forename: T N
authors.initials: TN
authors.lastname: Wight
mesh_terms: D000818:Animals; D001013:Aorta, Thoracic; D002103:Cadaverine / Q000031:analogs & derivatives* / Q000494:pharmacology; D002417:Cattle; D002478:Cells, Cultured; D011508:Chondroitin Sulfate Proteoglycans / Q000096:biosynthesis* / Q000302:isolation & purification; D002850:Chromatography, Gel; D003432:Cross-Linking Reagents; D003871:Dermatan Sulfate / Q000096:biosynthesis* / Q000302:isolation & purification; D004730:Endothelium, Vascular / Q000378:metabolism*; D005353:Fibronectins / Q000302:isolation & purification / Q000378:metabolism*; D007700:Kinetics; D008970:Molecular Weight; D011700:Putrescine / Q000378:metabolism; D011503:Transglutaminases / Q000378:metabolism*
chemical_list: D011508:Chondroitin Sulfate Proteoglycans; D003432:Cross-Linking Reagents; D005353:Fibronectins; C032649:dermatan sulfate proteoglycan; D003871:Dermatan Sulfate; D011503:Transglutaminases; C008542:monodansylcadaverine; D002103:Cadaverine; D011700:Putrescine