Protein-DNA interactions at recognition sites for the dioxin-Ah receptor complex.
Gel retardation analyses reveal a cluster of six binding sites for the liganded Ah receptor within a 700-base pair DNA domain upstream of the mouse CYP1A1 gene. The nucleotide sequences of the binding sites define a consensus recognition motif for the liganded receptor. The consensus motif is not symmetric. Alteration of the consensus motif produces a decrease in the receptor-DNA interaction. The ligand receptor binds as a monomer to its recognition motif and preferentially binds to double-stranded DNA. These observations reveal apparent differences between 2,3,7,8-tetrachlorodibenzo-p-dioxin and steroid hormones in their respective mechanisms of action.
Denison
M S
MS
Department of Pharmacology, Stanford University School of Medicine, California 94305.
Fisher
J M
JM
Whitlock
J P
JP
D000818:Animals; D001483:Base Sequence; D001667:Binding, Competitive; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics; D004247:DNA / Q000378:metabolism*; D004147:Dioxins / Q000378:metabolism*; D005796:Genes; D051379:Mice; D008969:Molecular Sequence Data; D000072317:Polychlorinated Dibenzodioxins / Q000378:metabolism* / Q000494:pharmacology; D018336:Receptors, Aryl Hydrocarbon; D011955:Receptors, Drug / Q000378:metabolism*; D014158:Transcription, Genetic
D004147:Dioxins; D000072317:Polychlorinated Dibenzodioxins; D018336:Receptors, Aryl Hydrocarbon; D011955:Receptors, Drug; D004247:DNA; D003577:Cytochrome P-450 Enzyme System