title: Plasma membrane proteins and glycoproteins from Chinese hamster cells sensitive and resistant to actinomycin D.
abstract: Plasma membrane proteins and glycoproteins have been isolated from Chinese hamster cells of the spontaneously transformed DC-3F parental cell line and the DC-3F/AD X line with a high level of acquired resistance to actinomycin D. Plasma membrane preparations from both cell lines band at 1.16 g/ml after isopycnic centrifugation. We present evidence to indicate differences in the leucylpeptide backbones of the antibiotic-sensitive cells and the drug-resistant DC-3F/AD X cells. In addition, there are differences in the plasma membrane glycopeptides of the two cell lines as revealed by sodium dodecyl gel electrophoresis. Drug-resistant cells synthesize a surface glycopeptide which is much larger than the major one present on the drug-sensitive cells. Both of these cell lines are devoid of 5'-nucleotidase and alkaline phosphatase activities. The role of plasma membrane protein differences in drug-resistant cells is discussed.
mesh_terms: D000818:Animals; D002460:Cell Line; D002462:Cell Membrane / Q000201:enzymology; D002471:Cell Transformation, Neoplastic; D006224:Cricetinae; D003609:Dactinomycin / Q000494:pharmacology; D004351:Drug Resistance; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D006020:Glycopeptides / Q000032:analysis; D006023:Glycoproteins / Q000032:analysis* / Q000096:biosynthesis; D008565:Membrane Proteins / Q000032:analysis* / Q000096:biosynthesis
chemical_list: D006020:Glycopeptides; D006023:Glycoproteins; D008565:Membrane Proteins; D003609:Dactinomycin