An upstream NF-Y-binding site is required for transcriptional activation from the hst promoter in F9 embryonal carcinoma cells.
Expression of hst (k-FGF, FGF-4), a member of the fibroblast growth factor gene family, is restricted to early stages of developing embryos and to embryonal carcinoma cells. In F9, which is a prototype of embryonal carcinoma cells expressing hst, the expression of hst gene is positively regulated by a downstream octamer motif that functions as an enhancer. We have investigated, by chloramphenicol acetyltransferase (CAT) reporter fusion gene analysis in F9, the cis-acting regulatory element within the hst promoter region that interacts with this enhancer. Electrophoretic mobility shift assay and methylation interference analysis showed that the hst promoter contains, in a segment termed Y, the sequence 5'-CTGATTGGCA-3', which closely resembles the consensus binding motif for the CCAAT-binding factor NF-Y. Deletions or mutations in this element substantially reduced expression of hst-CAT constructs. The nuclear factor binding to the Y segment of the hst promoter was indistinguishable from NF-Y, as inferred from interactions with specific anti-NF-Y monoclonal and polyclonal antibodies. We conclude that the expression of the hst gene in F9 is positively regulated by the coordinated interaction between an NF-Y-binding site and an octamer motif.
Hasan
S
S
Section of Bacterial Infection, Graduate School of Environmental Science, Hokkaido University, Sapporo, Japan.
Koda
T
T
Kakinuma
M
M
D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D022762:CCAAT-Enhancer-Binding Proteins; D002478:Cells, Cultured; D004247:DNA / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism*; D054278:Embryonal Carcinoma Stem Cells; D051519:Fibroblast Growth Factor 4; D005346:Fibroblast Growth Factors / Q000235:genetics*; D005786:Gene Expression Regulation; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D014411:Neoplastic Stem Cells / Q000378:metabolism; D011401:Promoter Regions, Genetic; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D014158:Transcription, Genetic
D022762:CCAAT-Enhancer-Binding Proteins; D004268:DNA-Binding Proteins; C496445:FGF4 protein, human; C496446:Fgf4 protein, mouse; D051519:Fibroblast Growth Factor 4; D011518:Proto-Oncogene Proteins; D005346:Fibroblast Growth Factors; D004247:DNA