title: The binding of [3H]oestradiol-receptor complexes to calf uterine chromatin.
abstract: Various aspects of the interaction of oestrogen-receptor complexes with calf uterine chromatin covalently coupled to cellulose were analysed. Partially purified [3H]oestradiol-receptor complexes were bound to intact, or partially deproteinized, chromatin resins. Proteins were removed from the chromatin-cellulose resins by extraction with high molarities of salt, including NaCl/urea, guanidine hydrochloride and guanidine thiocyanate. After extensive washing to remove the salt, [3H]oestradiol-receptor-complex solutions were added to the resins and the degree of binding was determined. The extent of [3H]oestradiol-receptor-complex binding to chromatin was enhanced by extraction of chromosomal proteins. By varying the molarity of the salt, and consequently the extent of protein removal, it was possible to resolve [3H]oestradiol-receptor-complex binding to guanidine thiocyanate-extracted chromatin into two components. Similarly, [3H]oestradiol-receptor-complex binding to guanidine hydrochloride-treated chromatin included three regions of enhanced binding capacity. The [3H]oestradiol-receptor-chromatin interaction was saturable with respect to both intact and salt-extracted resins. Thus uterine chromatin may contain three or more specific classes of acceptors for the oestrogen-receptor complex.
mesh_terms: D000818:Animals; D001665:Binding Sites; D002417:Cattle; D002482:Cellulose; D002843:Chromatin / Q000378:metabolism*; D004958:Estradiol / Q000378:metabolism*; D005260:Female; D019791:Guanidine; D006146:Guanidines; D066298:In Vitro Techniques; D011485:Protein Binding; D011959:Receptors, Estradiol; D011960:Receptors, Estrogen / Q000378:metabolism*; D012965:Sodium Chloride; D014508:Urea; D014599:Uterus / Q000378:metabolism*
chemical_list: D002843:Chromatin; D006146:Guanidines; D011959:Receptors, Estradiol; D011960:Receptors, Estrogen; D012965:Sodium Chloride; D004958:Estradiol; D014508:Urea; D002482:Cellulose; D019791:Guanidine