Interaction between the two ubiquitously expressed transcription factors NF-Y and Sp1.
The regulation of the rat fatty acid synthase gene by mediators such as diet, hormones, cAMP, sterols or retinoic acid is controlled by three NF-Y binding sites. All three sites have a neighbouring Sp1-binding GC-box. This NF-Y/Sp1 motif is conserved in the FAS promoters of rat, human, goose and chicken. We have previously shown cooperative binding of NF-Y and Sp1 to the promoter region at -500 coincident with a diet-induced DNAse I-hypersensitive site. Here, we show an in-vivo interaction of NF-YA with Sp1 using the yeast two-hybrid system. The interacting domains are located between amino acids 55 and 139 of the NF-Y subunit NF-YA and between amino acids 139 and 344 of Sp1. In addition, we show by co-immunoprecipitation direct interaction of NF-Y subunit NF-YA with Sp1 in extracts of rat hepatoma cells H4IIE. Furthermore, we demonstrate by the GST pull-down assay that NF-YA interacts physically with Sp1 in-vitro in the absence of DNA. Therefore, NF-Y can be added to the list of transcription factors interacting with Sp1.
Genetics and Microbiology Department, Institute of Food Research, Norwich Research Park, Colney, Norwich NR4 7UA, UK.
K
K
Roder
S S
SS
Wolf
K J
KJ
Larkin
M
M
Schweizer
D000818:Animals; D022762:CCAAT-Enhancer-Binding Proteins; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D064429:Fatty Acid Synthases / Q000235:genetics; D015971:Gene Expression Regulation, Enzymologic; D006801:Humans; D008114:Liver Neoplasms, Experimental / Q000378:metabolism / Q000473:pathology; D011233:Precipitin Tests; D011485:Protein Binding; D016329:Sp1 Transcription Factor / Q000235:genetics / Q000378:metabolism*; D014407:Tumor Cells, Cultured
D022762:CCAAT-Enhancer-Binding Proteins; D004268:DNA-Binding Proteins; D016329:Sp1 Transcription Factor; D064429:Fatty Acid Synthases