The rat liver receptor protein for 2,3,7,8-Tetrachlorodibenzo-p-dioxin: A comparison with steroid hormone receptors

The hydrodynamic properties of the salt-dissociated TCD receptor in rat liver cytosol (sedimentation coefficients, Strokes radius and molecular weight) all fall into the range described for monomeric steroid hormone receptors. In analogy to steroid hormone receptors, the TCDD receptor aggregates/oligomerizes under hypotonic buffer conditions. The chromatographic properties of the TCDD receptor on DEAE-Sepharose and hydroxylapatite are also very similar to those reported for steroid hormone receptors. Furthermore, preliminary data seem to indicate that the TCDD receptor, under certain conditions, might be a DNA-binding protein. However, the TCDD receptor seems to exhibit more pronounced hydrophobic properties than those reported for steroid hormone receptors. The TCDD receptor is firmly absorbed to pentyl Sepharose, whereas, under similar conditions, steroid receptors adsorb to alkyl-agaroses at chain lengths of 8-10 carbons.