Effects of tunicamycin, N-methyl-1-deoxynojirimycin, and manno-1-deoxynojirimycin on the biosynthesis of lactosaminoglycans in F9 teratocarcinoma cells.
F9 teratocarcinoma cells were incubated with D-[2-3H]mannose or D-[6-3H]galactose, and the labeled glycopeptides obtained after exhaustive digestion by pronase were fractionated on Bio-Gel P-6 before and after treatment by endo-beta-N-acetylglucosaminidase H. Tunicamycin almost completely inhibited the synthesis of lactosaminoglycans found in excluded glycopeptides of large molecular weight. Manno-1-deoxynojirimycin greatly inhibited the incorporation of labeled mannose into both lactosaminoglycan and complex oligosaccharides, while it greatly increased that into Man8GlcNAc and Man9GlcNAc oligosaccharides. In contrast, N-methyl-1-deoxynojirimycin only partially inhibited the incorporation into lactosaminoglycan and complex oligosaccharides, and caused the accumulation of Glc3Man7-9GlcNAc oligosaccharides. These results demonstrate that, in these cells, lactosaminoglycans are N-linked, and suggest that there is transfer of both glucosylated and nonglucosylated oligosaccharides from lipid to protein.
D017485:1-Deoxynojirimycin / Q000031:analogs & derivatives; D000606:Amino Sugars / Q000096:biosynthesis*; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002460:Cell Line; D005690:Galactose / Q000096:biosynthesis; D005944:Glucosamine / Q000031:analogs & derivatives* / Q000494:pharmacology; D006020:Glycopeptides / Q000302:isolation & purification; D008358:Mannose / Q000378:metabolism; D009844:Oligosaccharides / Q000302:isolation & purification; D011134:Polysaccharides / Q000096:biosynthesis*; D013724:Teratoma / Q000378:metabolism*; D014316:Tritium; D014415:Tunicamycin / Q000494:pharmacology*
D000606:Amino Sugars; D000900:Anti-Bacterial Agents; D006020:Glycopeptides; D009844:Oligosaccharides; D011134:Polysaccharides; C039448:lactosaminoglycan; D014316:Tritium; D014415:Tunicamycin; D017485:1-Deoxynojirimycin; D005944:Glucosamine; D008358:Mannose; D005690:Galactose; C033424:N-methyldeoxynojirimycin