Characterization of uterine estrogen receptors by size-exclusion and ion-exchange high-performance liquid chromatography.
This report presents the first application of ion-exchange high-performance liquid chromatography in the study of ER from the rabbit uterus. In the presence of sodium molybdate (20 mM), native ER was eluted as a sharp peak at 0.29 M NaCl by a linear salt gradient, but without molybdate, it resolved into 4 major peaks. Molybdate-stabilized ER from the DEAE column, similar to ER from crude cytosol, sedimented at the 6-8S region in low salt and 4S region in high salt linear sucrose gradients, and was excluded from size-exclusion HPLC. In contrast, dissociated ER subunits from DEAE eluates ranged from 3.5 to 4.5S, and showed differences in molecular weights in a size-exclusion column. These results show that the native ER is a large molecule which dissociates into smaller subunits in the absence of molybdate; each of the steroid-bound moieties differs in molecular weight and surface charge from the native molecule.
D000818:Animals; D002850:Chromatography, Gel / Q000379:methods; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D004958:Estradiol / Q000378:metabolism; D005260:Female; D008970:Molecular Weight; D011817:Rabbits; D011960:Receptors, Estrogen / Q000302:isolation & purification* / Q000378:metabolism; D014599:Uterus / Q000378:metabolism*
D011960:Receptors, Estrogen; D004958:Estradiol