Post-transcriptional control of IL-1 gene expression in the acute monocytic leukemia line THP-1.
The acute monocytic leukemia cell line THP-1 secretes predominantly IL-1 beta after treatment with bacterial lipopolysaccharide and tumour promoting phorbol ester (PMA). IL-1 alpha is also secreted, but represents less than 10% of the total IL-1 activity. This differential is reflected at the level of mRNA as IL-1 beta mRNA is more abundant than IL-1 alpha mRNA. Studies of transcription in isolated nuclei however indicate that each gene is transcribed at a similar rate, suggesting that post-transcriptional mechanisms regulate the relative abundance of IL-1 alpha and IL-1 beta mRNA. Measurement of RNA half life after addition of alpha-amanitin (an inhibitor of RNA polymerase II) indicate that IL-1 alpha mRNA is not as stable as IL-1 beta mRNA suggesting one mechanism for the different relative levels of RNA.
Turner
M
M
Charing Cross Sunley Research Centre, London, United Kingdom.
Chantry
D
D
Feldmann
M
M
D000546:Amanitins / Q000494:pharmacology; D003513:Cycloheximide / Q000494:pharmacology; D005260:Female; D005786:Gene Expression Regulation; D006207:Half-Life; D006801:Humans; D007375:Interleukin-1 / Q000235:genetics*; D007700:Kinetics; D007948:Leukemia, Monocytic, Acute / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000494:pharmacology; D012319:RNA Polymerase II / Q000037:antagonists & inhibitors; D012333:RNA, Messenger / Q000096:biosynthesis; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014158:Transcription, Genetic; D014407:Tumor Cells, Cultured
D000546:Amanitins; D007375:Interleukin-1; D008070:Lipopolysaccharides; D012333:RNA, Messenger; D003513:Cycloheximide; D012319:RNA Polymerase II; D013755:Tetradecanoylphorbol Acetate