Cycloheximide, an inhibitor of protein synthesis, prevents gamma-interferon-induced expression of class II mRNA in a macrophage cell line.
To characterize the mechanisms by which interferon gamma (IFN-gamma) upregulates major histocompatibility complex class II mRNA levels in mouse macrophages, we studied the effect of IFN-gamma on the transcription rate of class II genes and investigated the requirement for ongoing protein synthesis for the induction of class II mRNA expression. Nuclear run-off assays demonstrate that IFN-gamma induces class II mRNA at the transcriptional level. Treatment with cycloheximide, an inhibitor of protein synthesis, prevented the IFN-gamma-mediated accumulation of E alpha mRNA in the mouse macrophage cell line P388 D.1, indicating that induction of E alpha mRNA in P388 D.1 cells requires de novo synthesis of a protein intermediate. Our studies suggest that this putative protein factor is labile and required throughout the induction period.
D000818:Animals; D002460:Cell Line; D003513:Cycloheximide / Q000494:pharmacology*; D005786:Gene Expression Regulation / Q000187:drug effects; D005802:Genes, MHC Class II / Q000187:drug effects*; D000949:Histocompatibility Antigens Class II / Q000235:genetics; D007371:Interferon-gamma / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D007700:Kinetics; D008264:Macrophages / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism; D051379:Mice; D009693:Nucleic Acid Hybridization; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000096:biosynthesis* / Q000235:genetics; D011994:Recombinant Proteins / Q000037:antagonists & inhibitors / Q000276:immunology; D014158:Transcription, Genetic / Q000187:drug effects
D000949:Histocompatibility Antigens Class II; D012333:RNA, Messenger; D011994:Recombinant Proteins; D007371:Interferon-gamma; D003513:Cycloheximide