Influence of collagen lattice on the metabolism of small proteoglycan II by cultured fibroblasts.
Small dermatan sulphate proteoglycan II from cultured human skin fibroblasts interacts with type I collagen in vitro and in vivo. When fibroblasts are maintained in a type I collagen lattice the proteoglycan remains exclusively within the lattice, and its association with fibrils can be demonstrated immunocytochemically. On the basis of [35S]sulphate incorporation, small proteoglycan II comprises about 80% of total proteoglycans secreted by cells in monolayer culture. In a collagen lattice, fibroblasts down-regulate its synthesis to the level of large chondroitin sulphate/dermatan sulphate and of heparan sulphate proteoglycans, the synthesis of which remains unaffected. Compared with the product from monolayer cultures, small proteoglycan II from collagen gels contained a longer polysaccharide chain which is characterized by a larger proportion of disulphated and a smaller proportion of monosulphated glucuronic acid-containing disaccharides. The half-life varied between 60 and 110 h. It is suggested that the compositional differences between the proteoglycan from monolayer cultures and from cells in a collagen lattice are related to the slower intracellular trafficking of the proteoglycan under the latter culture conditions.
Greve
H
H
Institute of Physiological Chemistry and Pathobiochemistry, University of Münster, Federal Republic of Germany.
Blumberg
P
P
Schmidt
G
G
Schlumberger
W
W
Rauterberg
J
J
Kresse
H
H
D000328:Adult; D002478:Cells, Cultured; D002807:Chondroitin / Q000031:analogs & derivatives*; D011508:Chondroitin Sulfate Proteoglycans / Q000378:metabolism*; D003094:Collagen / Q000378:metabolism*; D003871:Dermatan Sulfate / Q000378:metabolism*; D015536:Down-Regulation; D004591:Electrophoresis, Polyacrylamide Gel; D005089:Exocytosis; D005347:Fibroblasts / Q000378:metabolism*; D006207:Half-Life; D006801:Humans; D007150:Immunohistochemistry; D007700:Kinetics; D008854:Microscopy, Electron; D008970:Molecular Weight; D011509:Proteoglycans / Q000378:metabolism*; D013431:Sulfates / Q000378:metabolism
D011508:Chondroitin Sulfate Proteoglycans; D011509:Proteoglycans; D013431:Sulfates; C032649:dermatan sulfate proteoglycan; D003871:Dermatan Sulfate; D002807:Chondroitin; D003094:Collagen