title: Inhibition of protein synthesis also inhibits synthesis of lipid-linked oligosaccharides.
abstract: Studies were initiated to determine whether the formation of lipid-linked oligosaccharides was coupled to the synthesis of protein. Canine kidney cells were grown with [2-3H]mannose or [3H]leucine in the presence of cycloheximide or puromycin and the effect of these inhibitors on the synthesis of proteins and lipid-linked oligosaccharides was measured. In all cases, the inhibition of protein synthesis resulted in a substantial inhibition in the incorporation of mannose into the lipid-linked oligosaccharides, although the synthesis of mannosyl-phosphoryl-dolichol was only slightly inhibited. Cycloheximide had no effect on the in vitro incorporation of mannose into lipid-linked oligosaccharides when GDP-[14C]mannose was incubated with aorta microsomal preparations. The inhibition of lipid-linked oligosaccharides was apparently not due to a decrease in the amount of glycosyltransferases as a result of protein degradation in the absence of protein synthesis, nor was it the result of a more rapid degradation of lipid-linked oligosaccharides. The inhibition also did not appear to be due to limitations in the available dolichyl-phosphate. The results suggest that the formation of lipid-linked oligosaccharides may be regulated by end product inhibition.
mesh_terms: D000818:Animals; D002460:Cell Line; D003513:Cycloheximide / Q000494:pharmacology*; D004285:Dogs; D004287:Dolichol Monophosphate Mannose / Q000096:biosynthesis*; D006017:Glycolipids / Q000096:biosynthesis*; D006023:Glycoproteins / Q000096:biosynthesis*; D007668:Kidney; D007700:Kinetics; D007930:Leucine / Q000378:metabolism; D008358:Mannose / Q000378:metabolism; D009844:Oligosaccharides / Q000378:metabolism*; D011105:Polyisoprenyl Phosphate Sugars / Q000096:biosynthesis*; D014176:Protein Biosynthesis / Q000187:drug effects*; D011691:Puromycin / Q000494:pharmacology*
chemical_list: D006017:Glycolipids; D006023:Glycoproteins; D009844:Oligosaccharides; D011105:Polyisoprenyl Phosphate Sugars; D011691:Puromycin; D004287:Dolichol Monophosphate Mannose; D003513:Cycloheximide; D007930:Leucine; D008358:Mannose