Characterization of the DNA-binding properties of the receptor for 2,3,7,8-tetrachlorodibenzo-p-dioxin.
The DNA-binding properties of the receptor for 2,3,7, 8-tetrachlorodibenzo-p-dioxin (TCDD) were investigated using chromatography on DNA-cellulose columns. A maximal binding of about 40% of the total receptor complex to DNA-cellulose was observed. In order to interact with DNA, the receptor must first bind TCDD. A heat-activation step followed by gel permeation chromatography using Sephadex G-25 increased the binding of the cytosolic receptor to DNA. The DNA-binding ability of the receptor was almost lost following mild proteolysis using trypsin or alpha-chymotrypsin, although these treatments did not reduce its ligand binding capacity and had no apparent effect on its size. Furthermore, pre-treatment of the DNA-cellulose column with an intercalating drug, ethidium bromide, resulted in inhibition of the binding of the TCDD-receptor complex to DNA, indicating that not only electrostatic interactions but also the configuration of DNA are of importance in receptor-DNA interactions.
D000818:Animals; D002499:Centrifugation, Density Gradient; D002846:Chromatography, Affinity; D002850:Chromatography, Gel; D002918:Chymotrypsin; D003600:Cytosol / Q000378:metabolism; D004268:DNA-Binding Proteins; D006358:Hot Temperature; D066298:In Vitro Techniques; D007364:Intercalating Agents; D008099:Liver / Q000378:metabolism; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D018336:Receptors, Aryl Hydrocarbon; D011955:Receptors, Drug / Q000378:metabolism*; D014357:Trypsin
D004268:DNA-Binding Proteins; D007364:Intercalating Agents; D018336:Receptors, Aryl Hydrocarbon; D011955:Receptors, Drug; D002918:Chymotrypsin; D014357:Trypsin