Binding of nuclear factors to the 5'-interferon consensus sequence of the HLA-A2 class I gene.
To investigate the regulatory role of the conserved interferon consensus sequence (ICS) found in the 5' flanking region of HLA class I genes, we studied the binding of nuclear proteins to the ICS of HLA-A2 gene (ICS-A2) by the gel shift assay. Nuclear extracts from several human cell lines expressing different levels of surface class I molecules reveal an ICS-A2-protein complex of similar mobility, the amount of which varies in a cell type-dependent manner. In some cell lines, interferon-gamma treatment decreased the level of this complex. The overlapping enhancer A element also competes for the formation of this ICS-A2-protein complex. Footprinting and methylation interference analyses demonstrate that nuclear protein(s) protect specific sequences within the ICS-A2 element, suggesting that these protein(s) may represent interferon-sensitive transcription factors.
Le Bouteiller
P
P
Department of Biology, Yale University, New Haven, Connecticut 06511.
Bogarad
L D
LD
Roberts
M R
MR
Barbosa
J A
JA
Ruddle
F H
FH
D001483:Base Sequence; D001665:Binding Sites; D004247:DNA / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000378:metabolism; D003850:Deoxyribonuclease I; D015789:HLA-A2 Antigen / Q000235:genetics*; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology*; D008745:Methylation; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000378:metabolism*; D014157:Transcription Factors / Q000378:metabolism; D014407:Tumor Cells, Cultured
D004268:DNA-Binding Proteins; D015789:HLA-A2 Antigen; D009687:Nuclear Proteins; D014157:Transcription Factors; D007371:Interferon-gamma; D004247:DNA; D003850:Deoxyribonuclease I