JBC, Vol. 252, Issue 10, 3324-3327, May, 1977
Estrogen-binding protein from rat preputial gland: purification and characterization
M. Feldman, W. Voigt and S. L. Hsia
Cytosol from the rat preputial gland has been shown to contain a protein
which binds both estrone and estradiol. The protein, after a 26-fold
purification from the cytosol of female Sprague-Dawley rats, migrated as
one band during electrophoresis in sodium dodecyl sulfate on acrylamide
gel. The electrophoretic mobility indicated a molecular weight of 15,000.
The association constant for estrone as determined by equilibrium dialysis
was 1.2 X 10(7) M-1, while that for 17beta-estradiol was 3.3 X 10(6) M-1.
Progesterone, cortisol, testosterone, or diethylstilbestrol did not bind to
the purified protein, whereas 17alpha-estradiol or estriol bound only
slightly. In the presence of retinoic acid, but not retinol, the binding of
estrone was reduced. Optimum binding for estrone was at pH 6.5 to 8.5.