Synthesis of the major oligosaccharide components of murine haemangioendothelioma cells.
Murine haemangioendothelioma cells in culture synthesize lactosaminoglycan-type glycoproteins which are found both associated with cells and secreted into the culture medium. Pronase-derived glycopeptides, prepared from the [3H]glucosamine-labeled glycoproteins that were secreted into the culture medium were found to contain about 10% of the labeled products as large size (Mr greater than 5000) 3H-labeled glycopeptides. In contrast, 40% of the cellular 3H-glycopeptides were found to be of this large size class of glycopeptides. These large size glycopeptides did not bind to Con A-Sepharose but did bind to Datura stramonium-agarose, from which they were eluted with chitobiose. The glycopeptides which did not bind to Datura-lectin were sulfated complex-type oligosaccharides which were not degraded by endo-beta-galactosidase. The glycopeptides which bound to Datura-lectin were degraded by endo-beta-galactosidase (or keratanase) to yield Gal----GlcNAc----Gal and glycopeptides, which were resistant to further endo-beta-galactosidase digestion and which no longer bound to Datura lectin-agarose. A major [3H]glucosamine-labelled glycoprotein (Mr approx. 75000) was found to be susceptible to endo-beta-galactosidase degradation and is probably the major cellular constituent having lactosaminoglycan-type side chains in these cells. An in vitro assay to measure leucocyte-haemangioendothelioma interactions indicated that treatment of haemangioendothelioma cells with endo-beta-galactosidase reduced leucocyte binding to these cells by 80%.
D000606:Amino Sugars / Q000032:analysis; D000818:Animals; D001665:Binding Sites; D002448:Cell Adhesion; D002478:Cells, Cultured; D055598:Chemical Phenomena; D002621:Chemistry; D002845:Chromatography / Q000379:methods; D004727:Endothelium / Q000166:cytology / Q000378:metabolism; D006020:Glycopeptides / Q000032:analysis; D006026:Glycoside Hydrolases; D006390:Hemangioendothelioma / Q000378:metabolism*; D006801:Humans; D007962:Leukocytes / Q000502:physiology; D051379:Mice; D009844:Oligosaccharides / Q000096:biosynthesis*; D011134:Polysaccharides / Q000032:analysis; D001616:beta-Galactosidase
D000606:Amino Sugars; D006020:Glycopeptides; D009844:Oligosaccharides; D011134:Polysaccharides; C039448:lactosaminoglycan; D006026:Glycoside Hydrolases; C026093:keratan-sulfate endo-1,4-beta-galactosidase; D001616:beta-Galactosidase