Chromatographic resolution of the type II estrogen binding site and a tyrosinase-like enzymatic activity from rat uterine nuclei.
Nuclear extracts from estradiol-treated rat uteri which contain type II estrogen binding sites have recently been found to also contain a tyrosinase-like estradiol metabolizing activity. A recent study suggested that both the binding and enzymatic activities are significantly increased in the presence of micromolar concentrations of copper and ascorbate, display a number of common biochemical sensitivities, and share similar ligand/substrate binding affinities. Levels of both activities are significantly increased in uterus in response to hormone (estrogen) stimulation. These and other similarities indicate a possible relationship between the enzymatic and binding activities. A detailed chromatographic examination of these two activities in the present study revealed that while the type II sites and estradiol metabolizing activity exhibited virtually identical chromatographic properties on DEAE-high-performance liquid chromatography they are readily resolved on other chromatographic matrices, including phosphocellulose, DNA-cellulose, and S-Sepharose. These results demonstrate that type II binding sites are distinct from the tyrosinase-like enzyme activity previously described in rat uterine nuclear extracts.
Densmore
C L
CL
Center for Biotechnology, Baylor College of Medicine, The Woodlands, Texas 77381.
Schauweker
T H
TH
Gregory
R R
RR
Webb
B
B
Garcia
E
E
Markaverich
B M
BM
D000818:Animals; D001205:Ascorbic Acid / Q000032:analysis; D002467:Cell Nucleus / Q000737:chemistry* / Q000187:drug effects / Q000201:enzymology; D002851:Chromatography, High Pressure Liquid; D003300:Copper / Q000032:analysis; D004958:Estradiol / Q000494:pharmacology; D005260:Female; D014442:Monophenol Monooxygenase / Q000032:analysis*; D051381:Rats; D017207:Rats, Sprague-Dawley; D011960:Receptors, Estrogen / Q000032:analysis*; D014599:Uterus / Q000737:chemistry* / Q000187:drug effects / Q000201:enzymology / Q000648:ultrastructure
D011960:Receptors, Estrogen; D004958:Estradiol; D003300:Copper; D014442:Monophenol Monooxygenase; D001205:Ascorbic Acid