These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Estriol and estrone interaction with the estrogen receptor. I. Temperature-induced modulation of the cooperative binding of [3H]estriol and [3H]estrone to the estrogen receptor.
    Author: Sasson S, Notides AC.
    Journal: J Biol Chem; 1983 Jul 10; 258(13):8113-7. PubMed ID: 6863279.
    Abstract:
    We investigated the calf uterine estrogen receptor's interaction with [3H]estriol and [3H]estrone and found that the receptor's cooperative binding is markedly dependent upon temperature and receptor concentration. With increasing temperature, the intensity of the estrogen receptor's cooperativity decreases: at 0 degrees C the Scatchard plot was convex and the Hill coefficient was 1.58 +/- 0.04 (n = 5), while at 30 degrees C the Scatchard plot approached linearity and the Hill coefficient was 1.03 +/- 0.02 (n = 3) for the binding of [3H]estriol with a receptor concentration of 10 to 12 nM. With increasing receptor concentration, the receptor's cooperativity gradually increased. At a receptor concentration of 1 nM, at 25 degrees C, with [3H]estriol the Hill coefficient was low, 1.03 +/- 0.02 (n = 3), while at approximately intracellular receptor concentration (20 nM) the Hill coefficient increased to 1.20 +/- 0.04 (n = 4). Similar results were observed with [3H]estrone. The cooperative interaction of the estrogen receptor with [3H]estriol or [3H]estrone is reversible and dependent upon temperature. The van't Hoff analysis of the apparent dissociation constant of the [3H]estrone- and [3H]estriol-receptor complexes indicates that a transition in the receptor's binding mechanism occurs at 15 degrees C. Therefore, measurements of ligand interactions with the estrogen receptor at 0 to 15 degrees C, may not reflect the binding mechanism of the receptor at more biologically relevant temperatures. The reduced, positively cooperative interactions of [3H]estriol and [3H]estrone with the estrogen receptor at 30 degrees C, in comparison with estradiol, decrease the presence of the activated receptor, which correlates with the partial agonist-antagonist activities of estriol and estrone observed in vivo.
    [Abstract] [Full Text] [Related] [New Search]