title: A DNA-binding fraction of mouse kidney 3-ketosteroid reductase: comparison with androgen receptors.
abstract: Since approximately 1% of 3-ketosteroid reductase (which metabolizes dihydrotestosterone (17 beta-hydroxyl-5 alpha-androstan-3-one] to 5 alpha-androstane-3 alpha, 17 beta-diol or 5 alpha-androstane-3 beta, 17 beta-diol) from mouse kidney cytosol adheres to DNA under conditions that allow virtually complete androgen receptor binding, these two DNA-binding activities were compared in cytosol extracts of mouse kidney and hypothalamus-preoptic area. This DNA-binding fractions of 3-ketosteroid reductase was distinguished from androgen receptor in several ways: (1) its pattern of elution from DNA-cellulose with steps of increasing NaCl concentration differed from that for receptors from wild-type kidney; (2) it was influenced differently by the mutation Tfm, both in level and in DNA-cellulose elution pattern; (3) in mouse kidney cytosol it was relatively stable at moderate (25 degrees C) temperatures which rapidly inactivated ligand-free androgen receptors in the same cytosols; (4) the DNA-binding was not proportional to androgen receptor levels between two wild-type tissues, the hypothalamus-preoptic area and kidney. By these criteria, a simple relationship of androgen receptors and a DNA-binding fraction of 3-ketosteroid reductase activity is unlikely.
mesh_terms: D015096:3-Hydroxysteroid Dehydrogenases / Q000235:genetics / Q000378:metabolism*; D045002:3-alpha-Hydroxysteroid Dehydrogenase (B-Specific); D015113:Androstane-3,17-diol / Q000378:metabolism; D000818:Animals; D002846:Chromatography, Affinity; D003600:Cytosol / Q000378:metabolism; D004247:DNA / Q000378:metabolism*; D013196:Dihydrotestosterone / Q000378:metabolism; D007031:Hypothalamus / Q000378:metabolism; D007668:Kidney / Q000201:enzymology*; D008297:Male; D051379:Mice; D011944:Receptors, Androgen / Q000235:genetics / Q000378:metabolism*; D011987:Receptors, Steroid / Q000378:metabolism*
chemical_list: D011944:Receptors, Androgen; D011987:Receptors, Steroid; D013196:Dihydrotestosterone; D015113:Androstane-3,17-diol; D004247:DNA; D015096:3-Hydroxysteroid Dehydrogenases; D045002:3-alpha-Hydroxysteroid Dehydrogenase (B-Specific)