Ets-1 is involved in transcriptional regulation of the chick inducible nitric oxide synthase gene in embryonic ventricular myocytes.
In order to elucidate roles of Ets family of transcription factors in transcriptional activation of inducible nitric oxide synthase (iNOS) genes, we analyzed the chick iNOS gene expression in cultured chick embryonic ventricular myocytes (CEVM). Deletional analysis and site-directed mutagenesis demonstrated that both the Ets/PEA3 site (-221 to -216 bp) and the kappaB site (-101 to -93 bp) of the 5'-flanking region of the chick iNOS gene were involved in the maximal activation of the lipopolysaccharide (LPS)-induced expression of the reporter (luciferase) gene, although the proximal kappaB site played the more essential role. Electrophoretic mobility shift assay revealed that LPS augmented the nuclear protein bindings to the Ets/PEA3 as well as kappaB motifs. Ets-1, one of the Ets proteins, was suggested to be bound to the Ets/PEA3 oligonucleotide. By Northern blot analysis, LPS was shown to induce iNOS mRNA in CEVM, along with a preceding increase in the levels of c-ets-1 mRNA. Ets-1 may be involved in the iNOS gene transcription in CEVM, presumably through interacting with the NF-kappaB.
Takahashi
T
T
Department of Cardiovascular Medicine, Graduate School of Medicine, University of Tokyo, Japan. takahashit-2im@h.u-tokyo.ac.jp
Sugishita
Y
Y
Kinugawa
K
K
Shimizu
T
T
Yao
A
A
Harada
K
K
Matsui
H
H
Nagai
R
R
D020816:Amino Acid Motifs; D000818:Animals; D001665:Binding Sites; D015152:Blotting, Northern; D002467:Cell Nucleus / Q000378:metabolism; D002642:Chick Embryo; D004305:Dose-Response Relationship, Drug; D017353:Gene Deletion; D006352:Heart Ventricles / Q000196:embryology*; D006801:Humans; D008070:Lipopolysaccharides / Q000378:metabolism / Q000494:pharmacology; D009132:Muscles / Q000166:cytology* / Q000196:embryology; D016297:Mutagenesis, Site-Directed; D016328:NF-kappa B / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000378:metabolism*; D052247:Nitric Oxide Synthase Type II; D009844:Oligosaccharides / Q000494:pharmacology; D050784:Proto-Oncogene Protein c-ets-1; D011518:Proto-Oncogene Proteins / Q000378:metabolism*; D050783:Proto-Oncogene Proteins c-ets; D012333:RNA, Messenger / Q000378:metabolism; D013997:Time Factors; D014157:Transcription Factors / Q000378:metabolism*; D014158:Transcription, Genetic; D015533:Transcriptional Activation
C494041:ETS1 protein, human; D008070:Lipopolysaccharides; D016328:NF-kappa B; D009844:Oligosaccharides; D050784:Proto-Oncogene Protein c-ets-1; D011518:Proto-Oncogene Proteins; D050783:Proto-Oncogene Proteins c-ets; D012333:RNA, Messenger; D014157:Transcription Factors; C496319:NOS2 protein, human; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II