Lipopolysaccharide induces phosphorylation of MAD3 and activation of c-Rel and related NF-kappa B proteins in human monocytic THP-1 cells.
Many effects of lipopolysaccharide (LPS) on gene expression, including that of human immunodeficiency virus (HIV), in monocytic cells are mediated by activation of kappa B DNA-binding proteins. However, the specific members of the NF-kappa B/Rel transcription factor family involved in the LPS response, and the mechanisms through which LPS-generated signals are transduced remain unclear. Here we show that LPS induces nuclear expression of c-Rel/p50 heterodimers as well as p50/p65 (NF-kappa B) kappa B DNA-binding complexes in human monocytic THP-1 cells. Nuclear localization of these proteins occurred concomitantly with a rapid decrease in their cytosolic levels and was independent of phorbol ester-sensitive protein kinase C. Within 24 h following LPS stimulation there was a striking increase in the levels of c-Rel, p105, and p50 in the cytosol. The increased levels of these proteins correlated with increases in the amounts of their mRNAs during LPS activation of THP-1 cells. LPS activation of THP-1 cells resulted in phosphorylation of MAD3 (an I kappa B-like protein), a rapid increase in MAD3 mRNA, and an increase in MAD3 protein by 2 h. Thus, LPS activation of human monocytic cells results in nuclear expression of c-Rel/p50 and p50/p65 (NF-kappa B) and induces phosphorylation of MAD3.
Department of Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232.
S R
SR
Cordle
R
R
Donald
M A
MA
Read
J
J
Hawiger
D000595:Amino Acid Sequence; D000906:Antibodies; D001483:Base Sequence; D015153:Blotting, Western; D002460:Cell Line; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D004742:Enhancer Elements, Genetic; D016325:HIV Long Terminal Repeat; D006801:Humans; D020672:I-kappa B Proteins; D007145:Immunoglobulin kappa-Chains / Q000235:genetics; D007948:Leukemia, Monocytic, Acute; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008969:Molecular Sequence Data; D009000:Monocytes; D000072000:NF-KappaB Inhibitor alpha; D016328:NF-kappa B / Q000235:genetics / Q000378:metabolism*; D009838:Oligodeoxyribonucleotides; D010455:Peptides / Q000276:immunology; D010766:Phosphorylation; D011505:Protein-Tyrosine Kinases / Q000378:metabolism*; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000378:metabolism*; D020569:Proto-Oncogene Proteins c-rel; D011519:Proto-Oncogenes; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014158:Transcription, Genetic / Q000187:drug effects
D000906:Antibodies; D004268:DNA-Binding Proteins; D020672:I-kappa B Proteins; D007145:Immunoglobulin kappa-Chains; D008070:Lipopolysaccharides; D016328:NF-kappa B; C000606204:NFKBIA protein, human; D009838:Oligodeoxyribonucleotides; D010455:Peptides; D011518:Proto-Oncogene Proteins; D020569:Proto-Oncogene Proteins c-rel; D012333:RNA, Messenger; D000072000:NF-KappaB Inhibitor alpha; D011505:Protein-Tyrosine Kinases; D013755:Tetradecanoylphorbol Acetate