Studies on sex-organ development. Isolation and characterization of an oestrogen receptor from chick Müllerian duct.
An oestradiol-binding macromolecule was observed in the left Müllerian duct of the 15-day female chick embryo. The embryonic receptor binds oestradiol with a high affinity and low capacity, having a Kd of 3.2 X 10(-9)M and a maximal number of sites of 5.45 fmol/10(6) cells in the left Müllerian duct. The receptor is protein in nature, as suggested by its susceptibility to proteolysis; in addition, it is organ- and steroid-specific. Judging by glycerol-gradient analysis, the hormone receptors in the cytosol are present in 8S and 4.5S forms, and the 8S form could be dissociated into a 4.5S form in the presence of 0.5M-KCl. A 4.5-6S receptor could be extracted from the nuclei. Under physiological salt conditions, the embryonic receptors bind to DNA-cellulose and can be eluted when the salt concentration is increased to 0.5M-KCl. Determination by isoelectric focusing indicates that the isoelectric point is 5.8 for the 8S and 6.9 for the 4.5S receptor.
D000818:Animals; D001665:Binding Sites; D001667:Binding, Competitive; D002467:Cell Nucleus / Q000378:metabolism; D002499:Centrifugation, Density Gradient; D002642:Chick Embryo; D002846:Chromatography, Affinity; D004958:Estradiol / Q000378:metabolism*; D005260:Female; D007700:Kinetics; D009095:Mullerian Ducts / Q000378:metabolism*; D011485:Protein Binding; D011506:Proteins / Q000302:isolation & purification / Q000378:metabolism*; D011956:Receptors, Cell Surface
D011506:Proteins; D011956:Receptors, Cell Surface; D004958:Estradiol