title: Post-translational processing of the glycoproteins of lymphocytic choriomeningitis virus.
abstract: Intracellular events in the synthesis, glycosylation, and transport of the lymphocytic choriomeningitis virus (LCMV) glycoproteins have been examined. We have shown by N-glycanase digestion that LCMV strain Arm-4 bears five oligosaccharides on GP-1 and two on GP-2. By pulse-chase labeling experiments in the presence of drugs which inhibit N-linked oligosaccharide addition and processing we demonstrate that addition of high mannose precursor oligosaccharides is necessary for transport and cleavage of the viral GP-C glycoprotein. Moreover, in the presence of tunicamycin which inhibits en bloc addition of these mannose-rich side chains, virus budding was substantially decreased and infectious virions were reduced by more than 1000-fold in the supernatant medium. Incubation in the presence of castantospermine, which permits addition of oligomannosyl-rich chains but blocks further processing, restored transport and cleavage of GP-C and maturation of virions. Finally, by temperature block experiments we have determined that maturation of GP-C oligosaccharides to an endoglycosidase H resistant form precedes cleavage to GP-1 and GP-2. The latter process is most likely to occur in the Golgi or post-Golgi compartment.
authors: Department of Neuropharmacology, Research Institute of Scripps Clinic, La Jolla, California 92037.
authors: K E
authors: KE
authors: Wright
authors: R C
authors: RC
authors: Spiro
authors: J W
authors: JW
authors: Burns
authors: M J
authors: MJ
authors: Buchmeier
mesh_terms: D017485:1-Deoxynojirimycin; D000470:Alkaloids / Q000494:pharmacology; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002460:Cell Line; D005944:Glucosamine / Q000031:analogs & derivatives / Q000494:pharmacology; D006023:Glycoproteins / Q000096:biosynthesis / Q000235:genetics*; D006026:Glycoside Hydrolases / Q000037:antagonists & inhibitors; D006031:Glycosylation; D006056:Golgi Apparatus / Q000378:metabolism; D007212:Indolizines; D007700:Kinetics; D008217:Lymphocytic choriomeningitis virus / Q000187:drug effects / Q000235:genetics* / Q000648:ultrastructure; D011499:Protein Processing, Post-Translational; D013696:Temperature; D014415:Tunicamycin / Q000494:pharmacology; D054836:Indolizidines
chemical_list: D017485:1-Deoxynojirimycin; D000470:Alkaloids; D000900:Anti-Bacterial Agents; D005944:Glucosamine; D006023:Glycoproteins; D006026:Glycoside Hydrolases; D007212:Indolizines; D014415:Tunicamycin; C037806:castanospermine; D054836:Indolizidines