Transcription stimulation of the Fas-encoding gene by nuclear factor for interleukin-6 expression upon influenza virus infection.
We previously found that the level of Fas, a cell surface receptor for an apoptosis signal, increases at the mRNA level in influenza virus-infected HeLa cells prior to their death by apoptosis. Here we investigated the mechanism of activation of the Fas-encoding gene expression upon influenza virus infection. Nucleotide sequences for the binding of nuclear factor for interleukin-6 expression (NF-IL6), also known as CCAAT/enhancer-binding protein beta, were repeated 8 times in the 5'-end region of the human FAS gene, spanning from -1360 to +320. This region directed the expression of a downstream marker gene when introduced into HeLa cells and the activity of the FAS gene promoter was stimulated about 2-fold upon influenza virus infection. Gene expression driven by the FAS promoter was activated when human NF-IL6 was overproduced in a DNA when human NF-IL6 was overproduced in a DNA co-transfection study. Moreover, the DNA-binding activity of NF-IL6 increased after infection with the virus, whereas the amount of NF-IL6 seemed unchanged. The results suggest that NF-IL6 is activated upon influenza virus infection through post-translational modification and that the modified factor stimulates the transcription of the human FAS gene.
Wada
N
N
Graduate School of Natural Science and Technology, Kanazawa University, Ishikawa, Japan.
Matsumura
M
M
Ohba
Y
Y
Kobayashi
N
N
Takizawa
T
T
Nakanishi
Y
Y
D000954:Antigens, Surface / Q000235:genetics*; D001483:Base Sequence; D022762:CCAAT-Enhancer-Binding Proteins; D003001:Cloning, Molecular; D004247:DNA; D004268:DNA-Binding Proteins / Q000502:physiology*; D006367:HeLa Cells; D006801:Humans; D015850:Interleukin-6 / Q000235:genetics*; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000502:physiology*; D009975:Orthomyxoviridae / Q000502:physiology*; D011401:Promoter Regions, Genetic; D014158:Transcription, Genetic; D019014:fas Receptor
D000954:Antigens, Surface; D022762:CCAAT-Enhancer-Binding Proteins; D004268:DNA-Binding Proteins; D015850:Interleukin-6; D009687:Nuclear Proteins; D019014:fas Receptor; D004247:DNA