Analysis of the epidermal growth factor receptor promoter: the effect of nuclear factor-kappaB.
The epidermal growth factor receptor gene is highly regulated and responsive to extracellular stimuli that control cell growth. We have identified five putative nuclear factor-kappaB (NF-kappaB) binding sites within the epidermal growth factor receptor (EGFR) promoter region by sequence analysis. We have analyzed the potential role of NF-kappaB family members in the regulation of the EGFR transcription. Electrophoretic mobility shift analysis demonstrated that the p50 and p49, subunit proteins of the NF-kappaB, bound to the EGFR promoter at four out of five of these sites. However, it was found that NF-kappaB could not transactivate the EGFR by cotransfection experiments with each NF-kappaB subunit, using p50, p65 and c-Rel and an EGFR promoter luciferase reporter. Treatment of cells with tumor necrosis factor (TNF)-alpha, which could degrade the I-kappaB and then result in translocation of NF-kappaB to nucleus, did not enhance EGFR promoter reporter gene transcription. Also, TNF-alpha did not induce EGFR expression at the protein level. These results indicate that even though purified NF-kappaB can bind to the putative sites, there is no evidence that NF-kappaB transactivates the EGFR promoter region.
Nishi
Hirotaka
H
Laboratory of Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892-4264, USA.
Neta
Gila
G
Nishi
Katsura H
KH
Akers
Latania M
LM
Rikiyama
Toshiki
T
Proctor
Kimberle N
KN
Murphy
Barbara A
BA
Johnson
Alfred C
AC
D016475:3T3 Cells; D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D001943:Breast Neoplasms; D016384:Consensus Sequence; D066246:ErbB Receptors / Q000235:genetics*; D005260:Female; D005786:Gene Expression Regulation; D017930:Genes, Reporter; D006801:Humans; D008156:Luciferases / Q000235:genetics; D051379:Mice; D008969:Molecular Sequence Data; D016328:NF-kappa B / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D021122:Protein Subunits / Q000378:metabolism; D014158:Transcription, Genetic; D015533:Transcriptional Activation; D014162:Transfection; D014407:Tumor Cells, Cultured
D016328:NF-kappa B; D021122:Protein Subunits; D008156:Luciferases; D066246:ErbB Receptors