Estrogen-Binding Proteins in the Oviduct of the Turtle,Chrysemys picta: Evidence for a Receptor Species

摘要: Estradiol-binding proteins in the reproductive tract of turtle, Chrysemys picta, were characterized. Cytosol was prepared from oviducts mature female turtles, and estradiol binding measured using charcoal adsorption glycerol density gradient centrifugation. A sex steroid-binding protein (SBP) similar to that found turtle plasma demonstrated oviduct cytosol. The characteristics this SBP-like as follows: Ka = 108 M"1; capacity, 10"l2 mol/mg protein; sedimentation coefficient, 6-7S low salt gradients. binds testosterone progesterone well 17Β-estradiol but does not bind diethylstilbestrol. No receptor-like activity could be these techniques. Explant culture DNA cellulose affinity chromatography used remove material before assay [3H]estradiol binding. Using techniques, a high (Ka 109 M"1), capacity (n 10 14 cytosol protein) receptor wa...