Effect of tunicamycin on the metabolism of low-density lipoproteins by control and low-density-lipoprotein-receptor-deficient human skin fibroblasts.
Preincubation of normal human skin fibroblasts with tunicamycin, which inhibits N-glycosylation of glycoproteins, resulted in a dose-dependent and reversible inhibition of binding and internalization of homologous low-density lipoproteins by the cells. The degradation of the internalized lipoproteins was not affected by the drug. Comparative studies with fibroblasts deficient in low-density-lipoprotein receptors indicated that tunicamycin exerts its inhibitory effect only via the receptor-mediated high-affinity binding and uptake of lipoproteins. These results suggest that expression of low-density-lipoprotein receptors on the cell surface of human skin fibroblasts depends on intact N-glycosylation.
D002460:Cell Line; D003513:Cycloheximide / Q000494:pharmacology; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism; D005944:Glucosamine / Q000031:analogs & derivatives*; D006801:Humans; D008077:Lipoproteins, LDL / Q000378:metabolism*; D008565:Membrane Proteins / Q000378:metabolism*; D011485:Protein Binding / Q000187:drug effects; D012867:Skin / Q000187:drug effects / Q000378:metabolism*; D014415:Tunicamycin / Q000494:pharmacology*
D008077:Lipoproteins, LDL; D008565:Membrane Proteins; D014415:Tunicamycin; D003513:Cycloheximide; D005944:Glucosamine