Androgen regulation of the androgen receptor of the quail uropygial gland: application of a [3H]mibolerone exchange assay

1986 ◽  
Vol 109 (3) ◽  
pp. 299-306 ◽  
Author(s):  
Y. Amet ◽  
J.-H. Abalain ◽  
S. di Stefano ◽  
J.-Y. Daniel ◽  
K. Tea ◽  
...  
Keyword(s):  
Androgen Receptor ◽  
Binding Sites ◽  
Androgen Receptors ◽  
Sodium Molybdate ◽  
Uropygial Gland ◽  
Sebaceous Glands ◽  
Androgen Action ◽  
Androgen Regulation ◽  
Exchange Technique

ABSTRACT An exchange assay for androgen receptors in the quail uropygial gland using [3H]mibolerone was established. The most efficient exchange conditions were 3 days of incubation at 15 °C. Under these conditions, androgen receptors were stable in the presence of sodium molybdate, and the exchange of [3H]mibolerone with endogenous testosterone bound to cytosolic or nuclear androgen receptors was maximal. Less than 5% of [3H]mibolerone-binding sites occurred in the extracted nuclear pellets. Using this exchange technique, it was shown that androgen receptors in the uropygial gland of photostimulated male quail or castrated quail treated with testosterone were activated and that their concentrations in both cytosolic and nuclear fractions were increased. These results confirm the androgen dependency of the quail uropygial gland, and show that it is an organ which can be used as a model for the study of androgen action in sebaceous glands. J. Endocr. (1986) 109, 299–306

Sex difference in the cytosolic and nuclear distribution of androgen receptor in mouse submandibular gland

1986 ◽  
Vol 108 (2) ◽  
pp. 267-273 ◽  
Author(s):  
S. Kyakumoto ◽  
R. Kurokawa ◽  
Y. Ohara-Nemoto ◽  
M. Ota
Keyword(s):  
Androgen Receptor ◽  
Nuclear Receptors ◽  
Binding Sites ◽  
Androgen Receptors ◽  
Dissociation Constants ◽  
Scatchard Analysis ◽  
Male And Female ◽  
Short Period ◽  
Almost All ◽  
Androgen Binding

ABSTRACT Cytosol and nuclear androgen receptors in submandibular glands of male and female mice were measured by an exchange assay at 0 °C. The binding of [3H]methyltrienolone to cytosol receptors in females was mostly saturated within a short period of incubation (3 h), whereas the saturation was much slower in males; suggesting that almost all of the cytosol receptors were unoccupied in females and the receptors were partially occupied in males. Nuclear receptors were extracted with pyridoxal 5′-phosphate (5 mmol/l) from nuclear fractions with 93–95% efficiency. The exchange of the bound steroids occurred by 24–48 h at 0 °C, suggesting that most of the nuclear androgen receptor was occupied. The binding was low at higher temperatures, probably due to inactivation of the receptor. Scatchard analysis showed that the apparent dissociation constants of cytosol and nuclear receptors were similar (0·8 and 0·9 nmol/l respectively) in both sexes. On the other hand, the number of androgen-binding sites in the nucleus was much higher in males than in females (1052 fmol/mg DNA and 32 fmol/mg DNA respectively), while the number in the cytosol was higher in females than in males (512 fmol/mg DNA and 368 fmol/mg DNA respectively). These observations show that androgen receptors exist mainly (74%) in the nuclei of males, while they exist mostly (94%) in the cytosol of females. J. Endocr. (1986) 108, 267–273

Increased recovery of androgen receptors from human prostate through the use of mersalyl: Evidence for androgen regulation of the binding sites in carcinomatous prostate

The Prostate ◽  
1986 ◽  
Vol 9 (1) ◽  
pp. 97-108 ◽  
Author(s):  
Marie Anne De Larminat ◽  
Leonardo Pasik ◽  
Oscar Bellora ◽  
Jorge Arturi ◽  
Carlos Scorticati
Keyword(s):  
Binding Sites ◽  
Androgen Receptors ◽  
Human Prostate ◽  
Androgen Regulation

ANDROGEN RECEPTORS IN PROLACTIN PRODUCING PITUITARY TUMOURS IN RATS

1977 ◽  
Vol 86 (2) ◽  
pp. 288-298 ◽  
Author(s):  
Arne Attramadal ◽  
Oddvar Naess ◽  
Egil Haug ◽  
Vidar Hansson ◽  
Ken Purvis
Keyword(s):  
Androgen Receptor ◽  
Binding Sites ◽  
Androgen Receptors ◽  
Sedimentation Coefficient ◽  
Ventral Prostate ◽  
Scatchard Analysis ◽  
Receptor Complex ◽  
Pituitary Tumours ◽  
High Affinity ◽  
Androgen Binding

ABSTRACT The androgen receptor system in prolactin secreting oestrogen induced pituitary tumours has been studied. The tumour cytosol was found to contain specific androgen receptors binding [3H]5α-dihydrotestosterone (DHT) and [3H] testosterone (T) with high affinity and low capacity. Scatchard analysis of the saturation data for T revealed one class of high affinity binding sites. The equilibrium constant of dissociation (Kd) was ∼ 4 × 10−10 m and the number of binding sites was calculated to be 12.8 femtomoles/mg protein. The sedimentation coefficient of the androgen receptor complex in low salt sucrose gradients was ∼ 7 S, the electrophoretic mobility (RF) in 3.25 % polyacrylamide gels ∼ 0.5 and the isoelectric point 5.8. The protein nature of the receptor was indicated by the finding that protease, but not DNase and RNase, eliminated androgen binding. Furthermore, the receptor was thermolabile and functionally dependent on free SH-groups since androgen binding was eliminated by heating 45°C for 30 min) and treatment with p-chloromercuriphenyl sulphonate (1 mm). Steroid specificity was tested in vitro by examining the competing efficiency of different unlabelled steroids for the binding of [3H]T. The affinity of DHT for the receptor was approximately twice that of testosterone while the binding affinity of oestradiol-17β and progesterone was very low. Cortisol had no affinity for the androgen receptor. The dissociation of the androgen receptor complex was very slow at 0°C (t ½ > 48 h). Thus, the characteristics of the cytoplasmic androgen receptors of the prolactin producing pituitary tumours are very similar to those of the androgen receptors earlier demonstrated in the anterior pituitary, hypothalamus, ventral prostate, epididymis and testis. The presence of specific androgen receptors in prolactin producing pituitary tumours indicates that androgen is involved in the regulation of synthesis and release of prolactin.

scholarly journals Anti-proliferative effects of progesterone antagonists in the primate endometrium: a potential role for the androgen receptor

Reproduction ◽  
2002 ◽  
pp. 167-172 ◽  
Author(s):  
RM Brenner ◽  
OD Slayden ◽  
HO Critchley
Keyword(s):  
Androgen Receptor ◽  
Mitotic Activity ◽  
Oestrogen Receptor ◽  
Potential Role ◽  
Reproductive Tract ◽  
Androgen Receptors ◽  
Proliferative Effect ◽  
Androgen Action ◽  
Progestin Treatment ◽  
Endometrial Proliferation

In women and non-human primates, treatment with anti-progestins suppresses oestrogen-dependent mitotic activity in the endometrial glands. This anti-proliferative effect is paradoxical, because anti-progestins do not bind to the oestrogen receptor. Although this phenomenon has been termed a 'non-competitive anti-oestrogenic effect', it does not occur in all species or in other regions of the primate reproductive tract, so is best referred to as an 'endometrial anti-proliferative effect'. The abundance of androgen receptors is greatly increased by anti-progestin treatment, especially in the glandular epithelium in non-human primates and women. Such an increase could lead to an enhancement of androgen action in the endometrium. As androgens suppress oestrogen-dependent endometrial proliferation, the increased abundance of androgen receptors could mediate the anti-proliferative effects of anti-progestin treatment. This brief review evaluates the implications of these findings.

Evidence for an androgen receptor in porcine Leydig cells

1987 ◽  
Vol 115 (1) ◽  
pp. 119-124 ◽  
Author(s):  
Veli Isomaa ◽  
Mauri Orava ◽  
Reijo Vihko
Keyword(s):  
Androgen Receptor ◽  
Binding Sites ◽  
Leydig Cells ◽  
Androgen Receptors ◽  
Cultured Cells ◽  
Binding Specificity ◽  
Culture Conditions ◽  
High Affinity ◽  
The Mean ◽  
Steroid Binding

Abstract. Cytosol and nuclear androgen receptor concentrations were measured in freshly prepared and cultured Leydig cells of immature pig testis with exchange assays using [3H]methyltrienolone as labelled ligand. Androgen receptors in Leydig cells had high affinity for [3H]methyltrienolone and steroid binding specificity typical of an androgen receptor. The mean receptor concentrations were 76 fmol/mg protein and 210 fmol/mg DNA for cytosol and nuclei, respectively. In sucrose gradients, cytosol androgen receptors sedimented in the 4 S region. The cells maintained androgen receptors under culture conditions. Exposure of cultured cells to [3H]methyltrienolone (10 nmol/l) resulted in accumulation of androgen receptors in the nuclei with maximal uptake by 1 h. We conclude that methyltrienolone binding sites with characteristics of androgen receptors were identified in both cytosol and nuclei of porcine Leydig cells.

Uropygial gland of quails, a new and convenient probe for the study of androgen action in sebaceous glands

1984 ◽  
Vol 111 (s27) ◽  
pp. 180-182 ◽  
Author(s):  
J. Y. DANIEL ◽  
J. H. ABALAIN ◽  
Y. AMET ◽  
H. H. FLOCH
Keyword(s):  
Uropygial Gland ◽  
Sebaceous Glands ◽  
Androgen Action

scholarly journals Functional mapping of androgen receptor enhancer activity

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Chia-Chi Flora Huang ◽  
Shreyas Lingadahalli ◽  
Tunc Morova ◽  
Dogancan Ozturan ◽  
Eugene Hu ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Androgen Receptor ◽  
Binding Sites ◽  
Gene Promoters ◽  
Strongly Correlated ◽  
Enhancer Activity ◽  
Drive Gene Expression ◽  
In Vitro Cell Lines ◽  
Drive Gene

Abstract Background Androgen receptor (AR) is critical to the initiation, growth, and progression of prostate cancer. Once activated, the AR binds to cis-regulatory enhancer elements on DNA that drive gene expression. Yet, there are 10–100× more binding sites than differentially expressed genes. It is unclear how or if these excess binding sites impact gene transcription. Results To characterize the regulatory logic of AR-mediated transcription, we generated a locus-specific map of enhancer activity by functionally testing all common clinical AR binding sites with Self-Transcribing Active Regulatory Regions sequencing (STARRseq). Only 7% of AR binding sites displayed androgen-dependent enhancer activity. Instead, the vast majority of AR binding sites were either inactive or constitutively active enhancers. These annotations strongly correlated with enhancer-associated features of both in vitro cell lines and clinical prostate cancer samples. Evaluating the effect of each enhancer class on transcription, we found that AR-regulated enhancers frequently interact with promoters and form central chromosomal loops that are required for transcription. Somatic mutations of these critical AR-regulated enhancers often impact enhancer activity. Conclusions Using a functional map of AR enhancer activity, we demonstrated that AR-regulated enhancers act as a regulatory hub that increases interactions with other AR binding sites and gene promoters.

Androgen receptor: acting in the three-dimensional chromatin landscape of prostate cancer cells

2011 ◽  
Vol 5 (1) ◽  
Author(s):  
Harri Makkonen ◽  
Jorma J. Palvimo
Keyword(s):  
Prostate Cancer ◽  
Androgen Receptor ◽  
Cancer Cells ◽  
Binding Sites ◽  
Target Genes ◽  
Three Dimensional ◽  
Regulatory Elements ◽  
Gene Promoters ◽  
Loop Formation ◽  
Prostate Cancer Cells

AbstractAndrogen receptor (AR) acts as a hormone-controlled transcription factor that conveys the messages of both natural and synthetic androgens to the level of genes and gene programs. Defective AR signaling leads to a wide array of androgen insensitivity disorders, and deregulated AR function, in particular overexpression of AR, is involved in the growth and progression of prostate cancer. Classic models of AR action view AR-binding sites as upstream regulatory elements in gene promoters or their proximity. However, recent wider genomic screens indicate that AR target genes are commonly activated through very distal chromatin-binding sites. This highlights the importance of long-range chromatin regulation of transcription by the AR, shifting the focus from the linear gene models to three-dimensional models of AR target genes and gene programs. The capability of AR to regulate promoters from long distances in the chromatin is particularly important when evaluating the role of AR in the regulation of genes in malignant prostate cells that frequently show striking genomic aberrations, especially gene fusions. Therefore, in addition to the mechanisms of DNA loop formation between the enhancer bound ARs and the transcription apparatus at the target core promoter, the mechanisms insulating distally bound ARs from promiscuously making contacts and activating other than their normal target gene promoters are critical for proper physiological regulation and thus currently under intense investigation. This review discusses the current knowledge about the AR action in the context of gene aberrations and the three-dimensional chromatin landscape of prostate cancer cells.

Study of androgen action in bone by analysis of androgen-receptor deficient mice

2002 ◽  
Vol 20 (6) ◽  
pp. 326-330 ◽  
Author(s):  
Takashi Sato ◽  
Hirotaka Kawano ◽  
Shigeaki Kato
Keyword(s):  
Androgen Receptor ◽  
Androgen Action ◽  
Deficient Mice
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