Activated steroid-receptor complex. Comparison of assays using DNA-cellulose or homologous nuclei.
When soluble steroid-receptor complexes are exposed to DNA-cellulose only activated complexes bind. The specificity of the binding was shown by its dependence on the presence of hormone during activation. However, prolonged incubation of non-activated steroid-receptor complexes with DNA-cellulose led to a progressive activation of these complexes. When the same hepatic cytosol containing heat-activated [3H]triamcinolone acetonide-receptor complexes was titrated by high concentrations of nuclei or DNA-cellulose the former bound 75% of the complexes, the later only 40%. This decreased binding was due on the one hand to a lower initial interaction between DNA-cellulose and activated complexes than between nuclei and these complexes and on the other hand to increased losses during washes when DNA-cellulose was used. For these reasons nuclei and not DNA-cellulose should be used when accurate measurements of the concentration of activated complexes are required. When only comparative data are needed DNA-cellulose may, however, be employed.
D000315:Adrenalectomy; D000818:Animals; D002467:Cell Nucleus / Q000378:metabolism; D002482:Cellulose; D003600:Cytosol / Q000378:metabolism; D004247:DNA; D007700:Kinetics; D008099:Liver / Q000378:metabolism; D008722:Methods; D051381:Rats; D011987:Receptors, Steroid / Q000032:analysis* / Q000378:metabolism; D014222:Triamcinolone Acetonide / Q000378:metabolism
D011987:Receptors, Steroid; D002482:Cellulose; D004247:DNA; D014222:Triamcinolone Acetonide