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Wasielewski R, Mengel M, Nolte M, Werner M. Influence of Fixation, Antibody Clones, and Signal Amplification on Steroid Receptor Analysis. Breast J 1998. [DOI: 10.1046/j.1524-4741.1998.410033.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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2
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Otto AM. A one minute pulse of estradiol to MCF-7 breast cancer cells changes estrogen receptor binding properties and commits cells to induce estrogenic responses. J Steroid Biochem Mol Biol 1995; 54:39-46. [PMID: 7632613 DOI: 10.1016/0960-0760(95)00076-c] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Changes in estradiol (E2)-binding parameters can be detected within minutes, while the estrogenic responses are manifested after several hours or days of continuous exposure to the steroid. The goal of this study was to determine the time of commitment for the induction of transcription-dependent responses in the human breast cancer cell line MCF-7. In cultures grown in steroid-deprived serum, a pulse of 1 nM E2 as short as 1 min was sufficient to maximally increase the level of the progesterone receptor, as determined by binding of the progestin [3H]ORG.2058 after 2 days, and to partially stimulate cell proliferation for 5 days. From uptake experiments it was calculated that after 1 min about 7000 E2 molecules were bound per cell, enough to occupy 5% of the approx. 150,000 estrogen receptors per cell. Preincubating cells with unlabelled E2 for 1 min lead to a loss of [3H]E2-binding capacity. As analysed by Scatchard plot, this loss was due to a decrease in the number of exchangeable binding sites and, to a lesser extent, to an increase in the dissociation constant. For up to 30 min of E2-incubation the level of receptor protein remained constant as determined by immunoassay with the anti-ER monoclonal antibodies D547 and H222. The dissociation kinetics of [3H]E2 bound by MCF-7 cells after a 5 min pulse were biphasic, with the slower phase having a rate of 2.3 x 10(-3) min. This rate is characteristic of the activated ER. The estrogenic response is thus committed by E2 within less than 1 min and evoked by the activation of a small fraction of estrogen receptors.
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Affiliation(s)
- A M Otto
- Lehrstuhl Pharmazeutische Chemie II, Institut für Pharmazie, Universität Regensburg, Germany
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Husen B, Adamski J, Szendro PI, Jungblut PW. Alterations in the subcellular distribution of 17 beta-estradiol dehydrogenase in porcine endometrial cells over the course of the estrous cycle. Cell Tissue Res 1994; 278:227-33. [PMID: 8001078 DOI: 10.1007/bf00414164] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The uteri of German landrace gilts slaughtered at different days of the cycle were processed for immunocytochemistry and biochemical analyses. Plasma was collected for hormone assays. The monoclonal antibody F1 against the structure-bound 17 beta-estradiol dehydrogenase of porcine endometrial epithelium was applied to rehydrated paraffin sections either as a direct, peroxidase-linked probe or in combination with a fluorescing secondary antibody. The oxidation of estradiol was measured in homogenates of tissue powdered in liquid nitrogen. Immunoreactivity was restricted to endometrial epithelium. In the glandular epithelium, faint dots of fluorescence became visible at day 4, which apparently coalesced to spherical structures of 2-4 microns diameter at the cell basis between days 11 through 17 before disappearing by day 18. A similar distribution was observed for the oxidation products of diaminobenzidine beginning with a faint uniform staining and followed by the appearance of intensely stained basal bodies persisting until day 17. Essentially the same time course was seen in the luminal epithelium but with a different distribution. Immunoreactive material amassed in the apical region of the cells, but the conspicuous aggregations were absent. Time course and intensities of the immunological responses are matched by the enzymatic activity measured in parallel. Both correlate with the plasma progesterone levels, suggesting an induction of the enzyme by the hormone. An involvement of the cytoskeleton in the sequence of subcellular distribution patterns is discussed.
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Affiliation(s)
- B Husen
- Max-Planck-Institut für Experimentelle Endokrinologie, Hannover, Germany
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Adamski J, Husen B, Thole HH, Groeschel-Stewart U, Jungblut PW. Linkage of 17 beta-oestradiol dehydrogenase to actin by epsilon-(gamma-glutamyl)-lysine in porcine endometrial cells. Biochem J 1993; 296 ( Pt 3):797-802. [PMID: 8280079 PMCID: PMC1137765 DOI: 10.1042/bj2960797] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
We report on the discovery of interactions of porcine endometrial 17 beta-oestradiol dehydrogenase with actin. The 17 beta-oestradiol dehydrogenase of porcine uteri is an essentially unidirectional enzyme compounded in specialized organelles. The enzyme activity in Brij 35 extracts of the particulate fraction of epithelial cells sedimenting between 1800 and 11,000 g(av). was collected by immunoadsorption and eluted at low pH. The eluate contained three proteins of 32, 45 and 80 kDa as shown by SDS/PAGE and silver staining. They were identified by amino acid sequencing and immunotyping as oestradiol dehydrogenase (32 kDa), actin (45 kDa) and a covalent dehydrogenase-actin complex (80 kDa). Disulphides, aldimines, periodate-degradable bonds and hydrophobic interactions were excluded as linkages in the 80 kDa protein. The epsilon-(gamma-glutamyl)-lysine nature of the covalent cross-link was recognized by narrow-bore h.p.l.c. analysis of enzymic digests of electro-eluted 80 kDa material. An involvement of the actin anchor in positioning of the oestradiol dehydrogenase-containing organelles according to metabolic requirements is discussed.
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Affiliation(s)
- J Adamski
- Max-Planck-Institut für experimentelle Endokrinologie, Hannover, Germany
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Adamski J, Husen B, Marks F, Jungblut PW. The 17 beta-oestradiol dehydrogenase of pig endometrial cells is localized in specialized vesicles. Biochem J 1993; 290 ( Pt 3):777-82. [PMID: 8457206 PMCID: PMC1132348 DOI: 10.1042/bj2900777] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Two monoclonal antibodies against the 17 beta-oestradiol dehydrogenase of pig endometrial cells have been used in localization studies with immunogold electron microscopy. The antibodies attach both to a fraction of dehydrogenase-rich cytoplasmic vesicles isolated from homogenates and to vesicles of similar appearance in cells. The vesicles are filled with electron-dense material. Their tagging intensity indicates a high degree of specialization. Endometrial cells from mature animals contain a host of dehydrogenase vesicles, and cells from prepubertal animals only a few. Functional aspects of the novel organelle are discussed.
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Affiliation(s)
- J Adamski
- Max-Planck-Institut für experimentelle Endokrinologie, Hannover, Germany
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Lopes MC, Tavares MC, Vale MG, Carvalho AP. Characterization of estrogen and antiestrogen binding to the cytosol and microsomes of breast tumors. J Steroid Biochem Mol Biol 1991; 39:343-52. [PMID: 1911424 DOI: 10.1016/0960-0760(91)90045-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The binding of [3H]estradiol and [3H]hydroxytamoxifen to the cytosol and microsomal fractions of several human breast tumors was investigated. By washing microsomal membranes with a KCl-free or a KCl-containing medium we could distinguish between intrinsic, extrinsic and contaminant estradiol binding sites in these membranes. We observed that treatment of the microsomes with low salt medium removes about 80% of the total estradiol binding sites, whereas 20% are not extractable. The concentration of unextractable [3H]estradiol binding sites in the microsomes varies in proportion to the level of cytosolic estrogen receptors (ER). About 10% of the total extranuclear specific estrogen binding sites was consistently found tightly associated to the microsomal fraction, which displays an affinity for estradiol (Kd = 0.1-0.6 nM) similar to that of the cytosolic ER. The displacement of [3H]estradiol with unlabeled hormone or with the antiestrogens, nafoxidine, enclomiphene and tamoxifen (TAM) exhibits identical IC50 values either in the cytosol or in the microsomal membranes. On the other hand, the microsomal fraction of breast tumors also binds [3H]hydroxyTAM, but with higher capacity and lower affinity than those of the cytosolic fraction. Furthermore, we did not observe correlation between the concentrations of ER and of antiestrogen binding sites (AEBS) in the tumors. These results indicate that microsomal membranes of human breast tumors contain estrogen binding sites which may be related to the cytosol ER recycling and that specific AEBS are predominantly localized in this membrane system. Furthermore, it is shown that the magnitude of estradiol binding to microsomes depends on the ER positive degree of the tumors, whereas the magnitude of the antiestrogen binding to the microsomes is independent of the ER status of the tumors.
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Affiliation(s)
- M C Lopes
- Center for Cell Biology and Hormonology, Faculty of Medicine, University of Coimbra, Portugal
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Moeller H, Goecke B, Herter F. Seasonal and diurnal changes of prostatic androgen receptor and circulating testosterone in young mature rats. RESEARCH IN EXPERIMENTAL MEDICINE. ZEITSCHRIFT FUR DIE GESAMTE EXPERIMENTELLE MEDIZIN EINSCHLIESSLICH EXPERIMENTELLER CHIRURGIE 1988; 188:451-62. [PMID: 2853435 DOI: 10.1007/bf01852003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Low- and high-salt (600 mM KCl) extractable androgen receptors were measured in the ventral prostate lobes of 70-day-old rats which were housed in constant environmental conditions (22 +/- 2 degrees C, 65 +/- 5% air humidity, light 6.00h-18.00h). Seasonal variations were observed during 2 years, exhibiting elevations in late summer and autumn and depressions in late winter and spring time. These fluctuations were superposed by steep changes from month to month. The maximum and minimum values of the low- and high-salt extractable receptors differed within 1 year by a factor 8.5 and 2.4, respectively. Both receptor fractions showed a diurnal rhythm as measured during 1 day in January with maximal concentrations at 9.00 h (low-salt: median = 1308 fmol/mg DNA) and minimal values at 18.00 (424) and 24.00 (230). The electrophoretic mobility in agar gel of pH 8.2 also showed a diurnal variation with maximal values at 18.00 h in either receptor fraction. Neither the seasonal nor the diurnal variations were correlated to the corresponding rhythms of serum testosterone concentrations. As steroid receptors may be regulated by neural transmission, in a final experiment the parasympathic innervation of the prostate was blocked by infiltrating the plexus pelvicus with a local anesthetic drug. One hour later, the total receptor concentration was not changed, while the ratio of low- to high-salt extractable receptors and the electrophoretic mobility of both fractions were elevated as compared to the control animals. This finding indicates that peripheral neural transmission rather than circulating testosterone may be involved in the regulation of androgen receptors in rat ventral prostate.
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Affiliation(s)
- H Moeller
- Dept. of Diagnostic Endocrinology, Children's Hospital, University of Tübingen, Federal Republic of Germany
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Mayer TK, Mooney RA. Laboratory analyses for steroid hormone receptors, and their applications to clinical medicine. Clin Chim Acta 1988; 172:1-33. [PMID: 2834119 DOI: 10.1016/0009-8981(88)90117-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- T K Mayer
- Department of Pathology and Laboratory Medicine, University of Rochester Medical Center, NY
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Sierralta WD, Szendro PI, Kallweit E, Jungblut PW. Biosynthesis and posttranslational finishing of the estradiol receptor. JOURNAL OF STEROID BIOCHEMISTRY 1987; 27:109-13. [PMID: 3695473 DOI: 10.1016/0022-4731(87)90301-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The time course of subcellular receptor distribution in porcine endometrial epithelium was studied after intrauterine administration of estradiol alone or in combination with puromycin. In untreated cells, the major proportion of receptor is associated with cytoplasmic membranes. The solubilization of receptor from isolated nuclei is independent of their estradiol content. Smooth cytoplasmic membranes are the site of origin of receptor which is swiftly translocated into the nucleus in a 1:1 ratio with the hormone after exposure of the cells to estradiol. Simultaneously administered puromycin delays receptor synthesis and reveals that the nuclear passage of receptor is terminated by receptor degradation. The synthesis of receptor proceeds in rough endoplasmic membranes. A subsequent finishing and deposition in smooth membranes depends on intact protein synthesis.
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Affiliation(s)
- W D Sierralta
- Max-Planck-Institut für experimentelle Endokrinologie, Hannover, Federal Republic of Germany
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Gómez-Benítez J, Díaz-Chico BN. Time course of anterior pituitary estrogen receptor after low 17 beta-estradiol doses in ovariectomized rats. JOURNAL OF STEROID BIOCHEMISTRY 1985; 23:77-80. [PMID: 4021493 DOI: 10.1016/0022-4731(85)90263-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The present paper describes the effect of three 17-beta-estradiol (E2) doses (1, 10 and 500 ng E2/kg) on the cytosolic and nuclear estrogen receptor content of anterior pituitary (Ap) of ovariectomized rats. The estrogen receptors were measured by [3H]E2 exchange in cytosol and crude nuclear fractions. Two hours after the administration of 10 or 500 ng E2/kg the Rc showed a depletion to 20-30% of preinjection level. The 1 ng E2/kg dose did not provoke any Rc depletion. The Rc replenishment was completed 5 h after injection of 10 ng E2/kg, but it was delayed to 10 h after injection of 500 ng E2/kg. An increased amount of Rc over the control levels was produced by 1 and 10 ng E2/kg doses, but not by the 500 ng E2/kg. The Rn level in Ap increased significantly after all E2 doses, and their highest levels were similar for 1, 10 and 500 ng E2/kg. These results suggest that some estrogenic responses like synthesis of the estrogen receptor proteins, can be elicited without previous significant Rc depletion. The relationships between Rc and Rn in Ap suggest an autoregulatory mechanism for the control of the cellular level of unbound estrogen receptors, that can be altered by the exogenous E2.
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Rossini GP. Steroid receptor recycling and its possible role in the modulation of steroid hormone action. J Theor Biol 1984; 108:39-53. [PMID: 6748680 DOI: 10.1016/s0022-5193(84)80167-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The fate of steroid-receptor complexes after their nuclear retention in target cells is not firmly established. Nuclear glucocorticoid- and androgen-receptor complexes could be recycled back to the cytosol in their responsive tissues, whereas this has not been clearly established for the case of progesterone and estrogen receptors. The models of steroid receptor recycling proposed so far involve release of chromatin-bound complexes into the cytosol, loss of steroid, and receptor inactivation. These receptors, however, can eventually be reactivated to a steroid binding form to reinitiate a cycle of steroid binding and further nuclear translocation. We propose that this model can represent a general aspect of steroid hormone action, provided that inactivation/reactivation processes occur in every steroid responsive system. A process involving a reversible receptor inactivation could play a major role in the control of steroid receptor recycling. It is proposed that a control on the extent of receptor available to steroid binding could result in a modulation of cellular responses to steroid hormones.
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Díaz Chico BN, Sosa González A, Gómez Benítez J. Relations between cytosolic and nuclear estrogen receptors in castrated rat uterus following low 17 beta-estradiol doses. JOURNAL OF STEROID BIOCHEMISTRY 1984; 20:1135-9. [PMID: 6727364 DOI: 10.1016/0022-4731(84)90356-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The effects of low 17 beta-estradiol (E2) doses (500, 10 or 1 ng/kg b X wt) on the uterine cytosolic (Rc) and nuclear (Rn) estrogen receptor content have been studied in adult-ovariectomized rats. The uterine Rc content after 500 ng E2/kg showed a depletion-replenishment-overshoot cycle. No significant Rc depletion could be observed with 1 or 10 ng E2/kg, but their corresponding overshoots were more intense than those observed for 500 ng E2/kg. The uterine Rn levels after 500 ng E2/kg increased during the Rc depletion and also during the replenishment and overshoot of Rc. With the lower doses Rn increased during the overshoot of Rc. In each dose Rn and Rc attained maximal values simultaneously. The return from Rc and Rn maxima to control levels was simultaneous in all cases. The high Rc overshoots obtained with 1 or 10 ng E2/kg could be the expression of a process of receptor synthesis induced by E2, more intense than the Rc breakdown produced by the complex formation with E2. The similar Rc and Rn time courses obtained with the lower doses suggest that the unbound receptor could enter into the nucleus. The simultaneous Rc and Rn decrease suggests the induction of a receptor degradation process affecting both cytosolic and nuclear compartments.
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Svec F. Comparison of glucocorticoid receptor depletion and the suppression of ACTH secretion in the AtT-20 cell. JOURNAL OF STEROID BIOCHEMISTRY 1984; 20:821-7. [PMID: 6323880 DOI: 10.1016/0022-4731(84)90390-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Glucocorticoids exert two effects on the cloned AtT-20 mouse pituitary tumor cell: they inhibit its production of ACTH and decrease its content of glucocorticoid receptors. In this paper the time courses of these two processes are compared to ascertain whether there is a link between them. The initial part of the time course of glucocorticoid receptor depletion was measured during an incubating of intact cells with 10 nM tritiated glucocorticoid. This showed that receptor depletion commenced at 4-6 h, but the half time of depletion was 30 h. Cell fractionation studies demonstrated that the decrease in receptor number occurred proportionately in both the nuclear and cytosolic fractions. The time course of dexamethasone suppression of ACTH secretion was measured under similar conditions. These studies showed that suppression was complete within 24 h. Comparison of these results led to the conclusion that although dexamethasone's effect on both receptor depletion and ACTH secretion is rapid, its effect on ACTH secretion is complete clearly before its effect on receptor depletion. Long term (3 week) dexamethasone incubations showed that even after dexamethasone had depleted the cell's receptor content to only a fraction of its initial value, its inhibitory effect on ACTH was undiminished. These results suggest that agonist action is not dampened with time. Taken together, these studies suggest that depletion is not a step in the mechanism of steroid-hormone action in the AtT-20 cell nor is it involved in diminishing the magnitude of agonist action. Instead, more likely, depletion is the process which removes redundant, spare glucocorticoid hormone receptor complexes.
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Ahdieh HB, Hamilton JM, Wade GN. Copulatory behavior and hypothalamic estrogen and progestin receptors in chronically insulin-deficient female rats. Physiol Behav 1983; 31:219-23. [PMID: 6356184 DOI: 10.1016/0031-9384(83)90122-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The effects of relatively short- or long-term diabetes on sexual receptivity and and proceptivity and on hypothalamic estrogen and progestin receptors were examined in rats fed regular chow or high fat diet. Ovariectomized, streptozotocin-induced chronically insulin deficient and normal rats received sequential treatments with 2 micrograms estradiol benzoate (EB) and 1 mg progesterone (P) 10 days following the induction of diabetes and were tested for lordosis and soliciting behaviors. Nondiabetic rats fed either diet displayed significantly higher lordosis and solicitation behaviors than chow-fed diabetics, and fat-fed diabetic animals displayed behavior levels intermediate to those of nondiabetic and chow-fed rats. Ten days after the induction of diabetes, the levels of hypothalamic estrogen receptors of chow-fed diabetics were significantly lower than nondiabetics with the fat-fed diabetic group showing intermediate levels. However, 70 days after streptozotocin treatment diabetic rats had significantly lower estrogen receptors than nondiabetics regardless of the diet. Treatment of long-term (70 days) diabetic rats with 1-2 U of U-100 Lente insulin for 24 hr or 7 days was ineffective in restoring the hypothalamic estrogen receptor concentrations to those of nondiabetics. Three weeks following induction of diabetes, induction of cytoplasmic progestin receptors by EB treatment was significantly impaired in diabetic animals fed either chow or high fat diet. Although the reproductive dysfunctions present in short-term diabetic female rats may be due in part to chronic fuel deprivation, it appears that the long-term maintenance of cytosol estrogen receptor level is dependent on other actions of insulin.(ABSTRACT TRUNCATED AT 250 WORDS)
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Jungblut P, Hekim N, Meyer H, Szendro P. Immunoreactivity of the core of estrogen receptors found in different subcellular compartments of target cells from a variety of mammalian species. ACTA ACUST UNITED AC 1983. [DOI: 10.1016/s0022-4731(83)80010-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Meyer HH, Jungblut PW. Purification of the steroid-binding core of porcine estrogen receptor. HOPPE-SEYLER'S ZEITSCHRIFT FUR PHYSIOLOGISCHE CHEMIE 1983; 364:757-68. [PMID: 6884995 DOI: 10.1515/bchm2.1983.364.1.757] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The steroid-binding core of estradiol receptor was purified from pig uterus cytosol by a protocol consisting of (1) adsorption to heparin-sepharose, (2) enzymatic release of the receptor core, (3) DEAE-chromatography, (4) Sephadex G-150 filtration and (5) chromatography on heparin-sepharose. The final product was approximately 18000-fold enriched over the starting material. It consisted of at least 18% core protein resembling dimeric microsomal receptor with a molecular mass of 75 kDa and an isoelectric point of 5.8 (microheterogeneity). A goat antiserum raised against the preparation contains immunoglobulins G precipitating estradiol-receptor complexes, and antibodies releasing the steroid from its binding site.
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Hekim N, Jungblut PW. Unspecific interactions of estrogen receptors with immunoglobulins and their absence in the tryptic receptor fragment. HOPPE-SEYLER'S ZEITSCHRIFT FUR PHYSIOLOGISCHE CHEMIE 1983; 364:607-11. [PMID: 6873884 DOI: 10.1515/bchm2.1983.364.1.607] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Immunoglobulin G preparations align unspecifically with all naturally occurring forms of the estradiol receptor, giving rise to soluble complexes of moderately increased sedimentation velocities. This interaction is not shown by the tryptic receptor fragment, which still contains the high affinity steroid binding site and the dimerization links of the native receptor.
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Kuppert PG, Spindler KD. Characterization of nuclear ecdysteroid receptor from crayfish integument. JOURNAL OF STEROID BIOCHEMISTRY 1982; 17:205-10. [PMID: 7109605 DOI: 10.1016/0022-4731(82)90123-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The existence of nuclear ecdysteroid receptors in isolated nuclei from crayfish integument was demonstrated. Nuclei were prepared from crayfish hypodermis by use of a modified Chauveau-method and exposed to [3H]-ecdysteroids. The nuclear hormone receptor complex sedimented at about 5 S and the available binding sites had a high affinity to [3H]-ecdysteroids. Treatment of the nuclei with pronase and DNase completed or partially reduced nuclear bound ecdysone, whereas RNase was without any effect. Competition of nuclear bound ecdysone by various steroids confirmed ponasterone A and kaladasterone as the best competitors followed by 20-OH-ecdysone and ecdysone, whereas compounds like poststerone, "triol" or hydrocortisone did not compete. If [3H]-20-OH-ecdysone was used as the radio-ligand, 20-OH-ecdysone was a better competitor than ecdysone indicating that there may be two different binding sites for ecdysone and 20-OH-ecdysone; this was further substantiated by the finding of two different number of binding sites for these steroids.
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Punnonen R, Lukola A. High-affinity binding of estrone, estradiol and estriol in human cervical myometrium and cervical and vaginal epithelium. J Endocrinol Invest 1982; 5:203-7. [PMID: 7175103 DOI: 10.1007/bf03348324] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The estrogen receptor concentrations in the cervical myometrium and ectocervical and vaginal epithelium were very low soon after the menstrual bleeding. The receptor concentrations were considerably higher in the middle of the proliferative phase and in postmenopausal patients treated with vaginal estrogens. In these two groups the estrogen receptor concentrations were lowest in the vaginal epithelium and highest in the cervical myometrium. In all three tissues studied, estradiol had the highest affinity to the receptor protein, followed by estriol and estrone. The binding was specific for all three estrogens whereas a 1000-fold excess of progesterone, dihydrotestosterone and testosterone was required in order to obtain competition for the estrogen receptor. Sedimentation analysis showed that estriol and estradiol were bound to macromolecules sedimentation analysis showed that estriol and estradiol were bound to macromolecules sedimenting at 9.0 S and 3.5-4.6 S whereas estrone was bound only to the 4.6 S binding protein.
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Jungblut PW, Gaues J, Görlich L, Hughes A, Kallweit E, Kielhorn J, Little M, Maschler I, McCann S, Parl F, Rosenfeld GC, Sierralta W, Stone G, Szendro PI, Teran C, Truitt AJ, Wagner RK. Intracellular actions of gonadal steroids. Exp Brain Res 1981; Suppl 3:37-60. [PMID: 7250250 DOI: 10.1007/978-3-642-45525-4_4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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