title: Identification of a putative progesterone receptor in the oviduct of a viviparous watersnake (Nerodia).
abstract: The steroid hormone progesterone is of particular interest in reproductive tract adaptations associated with the processing of embryonic materials in the evolution of viviparity. To further understand the mechanisms of action of this steroid, a progesterone receptor-like moiety was partially characterized in the oviduct of the viviparous snake Nerodia. Using DNA-cellulose and LH-20 column chromatography, a binding component was identified which exhibits high affinity (KA = 1.5 X 10(9) M-1) and low capacity (approximately 10(-11) M) binding of the synthetic progestin, R5020. In addition, the binding exhibited physiological steroid specificity, and was only identified in reproductive structures considered targets of progesterone action. These characteristics are consistent with the primary characteristics associated with steroid-receptor binding and are similar in both cytosolic and nuclear extract preparations.
mesh_terms: D000728:Androgens / Q000378:metabolism; D000818:Animals; D001667:Binding, Competitive; D002467:Cell Nucleus / Q000378:metabolism; D002846:Chromatography, Affinity; D003600:Cytosol / Q000378:metabolism; D005260:Female; D066298:In Vitro Techniques; D009928:Organ Specificity; D010057:Oviducts / Q000378:metabolism*; D010920:Placenta / Q000378:metabolism; D011247:Pregnancy; D011374:Progesterone / Q000378:metabolism; D011397:Promegestone / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism*; D012098:Reproduction; D012911:Snakes / Q000502:physiology*; D014599:Uterus / Q000378:metabolism; D014621:Vagina / Q000378:metabolism
chemical_list: D000728:Androgens; D011980:Receptors, Progesterone; D011374:Progesterone; D011397:Promegestone