Conservation of the DNA binding domain and other properties between porcine and rat glucocorticoid receptors.

Abstract Activated glucocorticoid receptor protein (GCR) was partially purified from porcine liver cytosol by sequential chromatography on phosphocellulose and DNA-cellulose using a modification of a protocol developed for purification of rat GCR [1–2]. This partially purified preparation, when separated by SDS-polyacrylamide gel electrophoresis and immunoblotted, indicated that a Mr = 94,000 protein band cross-reacts with a monoclonal antibody against rat GCR [3]. A nitrocellulose filter binding assay showed that both the partially purified porcine and rat GCRs interact specifically with a cloned synthetic 24 base pair deoxyoligonucleotide containing the GCR binding sequence in the first intron of the human growth hormone (hGH) gene [4]. This specific protein-DNA interaction is blocked by a single base pair change in the binding site. All three putative domains of the GCR molecule: the steroid binding, immunoreactive, and DNA binding have been conserved between two divergent species.