Binding of nuclear factors to the IFN-gamma consensus sequence of the human HLA-DR alpha gene: effects of IFN-gamma on tumor cell lines.
The binding of nuclear proteins from human tumor cells to synthetic double stranded oligonucleotides mimicking upstream regions of the HLA-DR alpha gene was studied. As the HLA-DR alpha gene is inducible by interferon(IFN)-gamma, nuclear extracts were also purified from IFN-gamma treated cells. Our data indicate that a) nuclear binding proteins (named IFN-gamma-B3 and Z-B1/B2) are detectable, specific for the IFN-gamma and Z boxes of the human HLA-DR alpha gene; b) both IFN-gamma-B3 and Z-B1/B2 are present in HLA-D negative cell lines and c) the content of IFN-gamma-B3 and Z-B1/B2 is not modulated by IFN-gamma treatment. These data suggest that the presence in the nuclear compartment of these factors, presumably necessary for the correct regulation of the HLA-DR alpha gene, is not sufficient to explain its differential constitutive and induced expression in a variety of in vitro cultured cell lines of different lineage.
Gambari
R
R
Institute of Chemical Biology, University of Ferrara, Italy.
Barbieri
R
R
Nastruzzi
C
C
Feriotto
G
G
Piva
R
R
Natali
P G
PG
Giacomini
P
P
D001483:Base Sequence; D015870:Gene Expression / Q000187:drug effects; D006684:HLA-DR Antigens / Q000235:genetics*; D006801:Humans; D007371:Interferon-gamma / Q000378:metabolism / Q000494:pharmacology*; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000378:metabolism*; D009841:Oligonucleotides / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis; D014407:Tumor Cells, Cultured / Q000187:drug effects
D006684:HLA-DR Antigens; D009687:Nuclear Proteins; D009841:Oligonucleotides; D012333:RNA, Messenger; D007371:Interferon-gamma