Protein-DNA interactions at a dioxin-responsive enhancer. Evidence that the transformed Ah receptor is heteromeric.

摘要: The Ah receptor in rat hepatic cytosol was transformed to a DNA-binding form by incubation vitro with the ligand 2,3,7,8-tetrachlorodibenzo-p-dioxin. covalently cross-linked bromodeoxyuridine-substituted DNA recognition motif exposure ultraviolet irradiation. Analyses of protein-DNA complexes gel electrophoresis and autoradiography imply that liganded is composed two protein components, whose molecular masses are about 110 100 kDa. Protease digestion studies suggest components have different primary structures. Photoaffinity labeling smaller ligand-binding component receptor. These findings constitute biochemical evidence heterodimer.