cis-acting sequences required for class II gene regulation by interferon gamma and tumor necrosis factor alpha in a murine macrophage cell line.
In this report, we have demonstrated that IFN-gamma and TNF-alpha increase expression of both the I-A and I-E region gene products on the surface of the myelomonocytic cell line WEHI-3, and that they mediate this increase via an increase in A alpha transcription. Constructs containing 5' deletion mutations of the A alpha promoter attached to the bacterial chloramphenicol acetyl transferase gene were used to delineate the minimum 5' flanking sequences required for promoter activity, and for inducibility by IFN-gamma and TNF-alpha. Approximately 115 bp of 5' sequences are required for minimum induction by IFN-gamma or TNF-alpha when the cytokines are present separately. This includes the three conserved promoter elements, the X, Y, and H boxes. Nested linker-scanner mutations demonstrated that additional regions were also critical for optimal induction by IFN-gamma or TNF-alpha. These include the kappa B-like enhancer and a TNF-alpha-specific sequence that we have tentatively called the T box. The T box sequence was also found in the promoter regions of the human HLA-DQ alpha and rat RT1.B alpha genes. Although the entire T box sequence element was not found in the other mouse class II genes, all class II alpha genes contained the SV40 core enhancer element in the regions included by the T box. Mouse class II beta genes appear to contain neither the T box nor the core enhancer element in this region, suggesting differential regulation of class II alpha and beta genes by TNF-alpha.
Freund
Y R
YR
Department of Immunology and Infectious Diseases, Palo Alto Medical Foundation, California 94301.
Dedrick
R L
RL
Jones
P P
PP
D000818:Animals; D000911:Antibodies, Monoclonal; D001483:Base Sequence; D002460:Cell Line; D002462:Cell Membrane / Q000276:immunology; D015500:Chloramphenicol O-Acetyltransferase / Q000235:genetics; D004247:DNA / Q000235:genetics; D004742:Enhancer Elements, Genetic; D005786:Gene Expression Regulation; D005802:Genes, MHC Class II; D000949:Histocompatibility Antigens Class II / Q000032:analysis / Q000235:genetics; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology*; D008156:Luciferases / Q000235:genetics; D008264:Macrophages / Q000187:drug effects / Q000276:immunology*; D051379:Mice; D008969:Molecular Sequence Data; D010957:Plasmids; D011401:Promoter Regions, Genetic; D011994:Recombinant Proteins / Q000494:pharmacology; D012689:Sequence Homology, Nucleic Acid; D012984:Software; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*
D000911:Antibodies, Monoclonal; D000949:Histocompatibility Antigens Class II; D011994:Recombinant Proteins; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma; D004247:DNA; D008156:Luciferases; D015500:Chloramphenicol O-Acetyltransferase