Bacterial lipopolysaccharide induces mRNA expression of an IkappaB MAIL through toll-like receptor 4.
Molecule possessing ankyrin-repeats induced by lipopolysaccharide (MAIL) is a nuclear IkappaB protein recently identified as a molecule appearing in immunocompetent organs after administration of bacterial lipopolysaccharide (LPS). Participation of Toll-like receptor (TLR) 4, which is a major form of LPS receptors, in the LPS-induced MAIL expression was investigated. When a human myelomonocytic cell line U937 was treated with phorbol 12-myristate 13-acetate for 3 days, the LPS-induced MAIL expression was much potentiated in parallel with an increase in TLR4 expression. The MAIL induction was attenuated when the cells were treated with a neutralizing antibody against TLR4. The in vivo induction of MAIL in the spleen was smaller in mice having a missense mutation of the Tlr4 gene than in normal control mice. These results collectively indicate that TLR4 contributes, at least in part, MAIL induction after LPS stimulation.
Kitamura
Hiroshi
H
Department of Biomedical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan.
Kanehira
Katsushi
K
Shiina
Takahiko
T
Morimatsu
Masami
M
Jung
Bae Dong
BD
Akashi
Sachiko
S
Saito
Masayuki
M
D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D029721:Drosophila Proteins; D005786:Gene Expression Regulation / Q000187:drug effects*; D006801:Humans; D020672:I-kappa B Proteins; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008297:Male; D008562:Membrane Glycoproteins / Q000378:metabolism*; D051379:Mice; D008809:Mice, Inbred C3H; D009687:Nuclear Proteins / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000378:metabolism*; D051197:Toll-Like Receptor 4; D051193:Toll-Like Receptors; D014407:Tumor Cells, Cultured; D020298:U937 Cells
D048868:Adaptor Proteins, Signal Transducing; D029721:Drosophila Proteins; D020672:I-kappa B Proteins; D008070:Lipopolysaccharides; D008562:Membrane Glycoproteins; C417234:NFKBIZ protein, human; C485947:Nfkbiz protein, mouse; D009687:Nuclear Proteins; D012333:RNA, Messenger; D011956:Receptors, Cell Surface; C495345:TLR4 protein, human; D051197:Toll-Like Receptor 4; D051193:Toll-Like Receptors