[3H]-TCDD has been used to photoaffinity label the Ah receptor from Wistar rat hepatic cytosol. Preliminary experiments with crude hepatic cytosol showed that photocovalent attachment of TCDD had occurred, but that most of the adducts were bound non-specifically. Hydroxylapatite chromatography, ion exchange chromatography and preparative sucrose density centrifugation each gave ca. 3-5 fold purification of the Ah receptor compared with crude cytosol. Photolysis of the partially purified preparations with [3H]-TCDD gave a 3-fold increase in the amounts of specifically bound covalent adducts, with an overall yield of ca. 30%. SDS-polyacrylamide gel electrophoresis of the photolysate showed the specific photo-incorporation of the radiolabel into the 106, 90, 72, and 60 kDa regions of the gel.
ASJC Scopus subject areas
- Environmental Engineering
- Environmental Chemistry
- Health, Toxicology and Mutagenesis