| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas 77030
Address all correspondence and requests for reprints to: Bert W. O’Malley, Department of Molecular and Cellular Biology, Baylor College of Medicine, One Baylor Plaza, Houston, Texas 77030. E-mail: berto{at}bcm.tmc.edu.
 |
ABSTRACT |
|---|
 TOP ABSTRACT INTRODUCTIONRESULTSDISCUSSIONMATERIALS AND METHODSREFERENCES |
|---|
|
INTRODUCTION |
|---|
|
TOPABSTRACTINTRODUCTIONRESULTSDISCUSSIONMATERIALS AND METHODSREFERENCES |
|---|
Understanding the role of the SRC family members in regulating PR-dependent gene transcription and function in vivo has been aided by the ablation of these genes in mice (17, 18, 19). The initial analyses of phenotypes of SRC-1(–/–) mice revealed that SRC-1 plays a role in modulating PR function in the uterus because a significantly reduced uterine decidual response was detected in SRC-1(–/–) mice even though these mice were viable and fertile (17). During development, mammary ducts grew extensively and occupied almost the entire mammary fat pad by 8 wk of age. However, the extent number of mammary ductal branches was substantially reduced in age-matched SRC-1(–/–) mice. These phenotypes resemble in part the phenotypes of PR(–/–) mice (20, 21). PR(–/–) mice exhibited less dichotomous and lateral side branching and defective alveolar development (21). Interestingly, the rudimentary ductal network emanating from the nipple in estrogen receptor (ER)-
(–/–) females clearly demonstrated that estrogen (E2) /ER- signaling is essential for mammary ductal morphogenesis and lobuloalveolar development (22, 23). The similarity of these defects implicates the possible involvement of SRC-1 in PR and/or ER- function during mammary gland development during an extended hormonal exposure, as seen in pregnancy.
The analysis of SRC-3(–/–) mice also revealed that SRC-3 plays an important role in female reproduction. The mammary gland, a target organ of ovarian steroids, expresses SRC-3 (24). Deletion of SRC-3 in mice results in defects of mammary gland development, including retardation of ductal growth and penetration of ductal branches (24), an observation similar to what is observed in both PR(–/–) and ER-(–/–) mice. These similarities imply that SRC-3 likely plays some role in PR- and/or ER--mediated mammary gland development.
Although ablation of coactivator genes in mice suggested that both SRC-1 and SRC-3 could regulate reproductive developmental processes in the uterus and mammary glands through PR or ER-, it was unclear as to whether PR uses specific SRCs for physiologic functions in adult animals during hormone exposure to E2 and progesterone (P4), as seen in pregnancy. To address this question, we employed our PR activity indicator (PRAI) mice crossed to either SRC-1 or SRC-3 null background mice as our experimental models. The PRAI mouse system contains a transgenic modified PR bacterial artificial chromosome in which the DNA binding domain of the PR was replaced with the yeast Gal 4 DNA binding domain. A humanized green fluorescent protein (hrGFP) reporter controlled by the upstream activating sequences for the Gal 4 gene (UASG) was inserted in tandem with the modified PR gene (25). Tissue-specific and cellular compartment-specific expression of Gal4-PR and hrGFP expression faithfully replicated endogenous PR and its target gene expression in the mouse under various endocrine states (25). Using this PRAI mouse model crossed into either an SRC-1 or SRC-3 null background, we demonstrated that for its physiologic functions, PR selectively requires the SRC-3 coactivator in breast, but in contrast, it requires the SRC-1 coactivator in uterus.
|
RESULTS |
|---|
|
TOPABSTRACTINTRODUCTIONRESULTSDISCUSSIONMATERIALS AND METHODSREFERENCES |
|---|
). To investigate whether Gal4-PR expression was correlated with endogenous PR in the LECs, dual immunofluorescence was conducted with anti-PR and anti-Gal4-DBD antibodies. This analysis revealed that Gal4-PR was only expressed in the PR-positive LECs (Fig. 1, B–D), thereby recapitulating the expression pattern of endogenous PR in the appropriate LEC compartment of the mammary gland.
|
, A and B). This observation substantiated that PR expression occurs in most LECs of the mammary gland after hormone treatment (Fig. 1A
). Consequently, it was not possible to determine whether hrGFP expression occurs in only PR-positive cells under this hormonal regimen. To clearly investigate whether hrGFP expression coincides with PR expression in the mammary LECs, we acutely treated PRAI mice with P4. A previous study revealed that acute treatment with P4 does not increase PR-positive LECs and, thus, not all LECs will be PR positive under this condition (27). Ovariectomized mice were injected with P4 and their mammary glands were collected for analysis 6 h after P4 injection. Dual immunofluorescence staining clearly demonstrated that hrGFP (Fig. 1E) was expressed only in the PR-positive LECs (Fig. 1, F–H). Therefore, Gal4-PR tightly regulates hrGFP expression in the LE of the mammary gland in PRAI mice in a manner similar to that of endogenous PR.
|
, A and B) and SRC-1(–/–) mice (Fig. 2C). Unexpectedly, hrGFP expression (PR activity) in the mammary glands of SRC-1(–/–) mice was not different from that of wild-type mice (Fig. 2E). Our data suggest that PR activity induced by chronic E2 + P4 treatment in the mammary LE is not dependent on the presence of SRC-1.
To investigate whether SRC-3 is required for PR transcriptional activity in LE of the mammary gland, PRAI transgenic mice were crossed with SRC-3(+/–) mice to generate bigenic PRAI-SRC-3(–/–) mice. The bigenic mice were chronically treated with E2 + P4 and PR activity in the LE compartment of the mammary gland was determined by comparing hrGFP expression in wild-type (Fig. 2B) and SRC-3(–/–) mice (Fig. 2D). After hormonal treatment, wild-type mice showed increased expression of hrGFP in the LECs; hrGFP expression did not increase in the LECs of SRC-3(–/–) mice (Fig. 2E). In contrast to results with SRC-1, SRC-3 is essential for the PR activity observed in the LECs of mammary gland.
To substantiate the validity of this differential hrGFP expression pattern, we examined the expression levels of the endogenous PR target genes, Wnt-4 and Amphiregulin (Arg) together with hrGFP, by in situ hybridization. Consistent with hrGFP protein expression, hrGFP mRNA increased in the LECs of both of PRAI (Fig. 2, F and G) and PRAI-SRC-1(–/–) mice (Fig. 2H) but not in PRAI-SRC-3(–/–) mice (Fig. 2I) in response to chronic E2 + P4 treatment (Fig. 2J). Similarly, Wnt-4 and Arg mRNA levels were induced in the LE compartment of PRAI (Wnt4, Fig. 2, K, L, and O; Arg, Fig. 2, P, Q, and T) and PRAI-SRC-1(–/–) mice (Wnt4, Fig. 2, M and O; Arg, Fig. 2, R and T) but not in PRAI-SRC-3(–/–) mice (Wnt4, Fig. 2, N and O; Arg, Fig. 2, S and T). Similarly, induction of another PR target gene, KLF4, also was affected when SRC-3 is deleted (Fig. 2U). There was a reduction, although to a lesser extent than for SRC-3(–/–) mice, of KLF4 expression in SRC-1 mutant mice (Fig. 2U). Our data indicate that SRC-3, but not SRC-1, is the primary coactivator for PR in the LECs of the mammary gland.
PR Colocalizes with Both SRC-1 and SRC-3 in the LE Compartment of the Mammary Gland
The above observation raises the question as to whether SRC-1 and SRC-3 are expressed in the same PR-positive cells of mammary LE to modulate PR activity in response to E2 + P4. To address this question, we investigated the spatial expression of PR, SRC-1 and SRC-3 by dual immunofluorescence in the mammary glands of mice treated with E2 + P4. All PR-positive cells in the LE expressed SRC-1 (Fig. 3, A–C), but some PR-negative LECs also expressed SRC-1 (yellow arrow in Fig. 3D). Similarly, all PR-positive cells in the LE compartment also expressed SRC-3 (Fig. 3, E–G). In contrast to SRC-1, SRC-3 was not expressed in PR-negative cells (yellow arrow in Fig. 3H). Collectively, these data support our prior results showing that although PR colocalizes with both SRC-1 and SRC-3 in the LE, only SRC-3 functions to regulate PR-mediated transcription in response to E2 + P4. The presence of SRC-1+PR– cells in the LE compartment suggests the possibility that SRC-1 could modulate mammary gland development through a PR-independent pathway.
|
). In wild-type mice, E2 + P4 treatment increased the level of PR expression (Fig. 4, A and B). Similarly, PR levels also were increased in LECs of either SRC-1(–/–) (Fig. 4C) or SRC-3(–/–) mice (Fig. 4D). Therefore, we interpret that neither SRC-1 nor SRC-3 is required for the regulation of PR expression in the LE compartment of the mammary gland. Furthermore, the decrease in PR activity in the LE of SRC-3(–/–) mice was not associated with decreased PR levels.
|
). Similarly, the mRNA levels of both coactivators did not change in either SRC mutant mice upon E2 + P4 treatment (Fig. 4E). For example, SRC-2 and SRC-3 mRNA expression in the mammary gland of SRC-1(–/–) mice did not differ from that of wild-type mice; SRC-1 and SRC-2 mRNA levels in mammary gland of SRC-3(–/–) mice also were not different than that of wild-type mice (Fig. 4E). Thus, individual SRCs do not regulate genetic expression of the other SRCs in the mammary gland.
Although mRNA levels of SRCs did not change, we considered that the protein levels could be affected by hormone treatment and by SRC gene deletion. We examined the protein levels of PR coactivators in the LE compartment of the mammary gland. In contrast to the lack of effect of SRC mRNA levels in wild-type mice, the protein levels of all SRC coactivators were significantly induced in the LE compartment of the mammary gland after chronic E2 + P4 treatment (SRC-1—Fig. 4, F and G; SRC-2—Fig. 4, K and L; SRC-3—Fig. 4, P and Q). Therefore, chronic E2 + P4 treatment could influence PR activity by increasing the stability of SRC proteins in the LE compartment of the mammary gland. The protein levels of all SRCs in LE were assayed in wild-type and SRC null mice in response to chronic E2 + P4 treatment. In all oil control conditions, PR and SRC expression levels in the mammary gland of each of the SRC KO mice were not significantly different from wild-type mice (data not shown). Interestingly, the SRC-2 protein level was higher in SRC-1(–/–) mice than in the wild-type littermates (Fig. 4, M and O); SRC-3 protein level was not changed in both wild-type (Fig. 4Q) and SRC-1(–/–) mice (Fig. 4, R and T). Thus, a compensatory increase in the SRC-2 protein level could explain in part why PR activity in the LE compartment was not blocked by the deletion of SRC-1.
In contrast with SRC-1(–/–) mice (Fig. 4, H, M, and R), both SRC-1 (Fig. 4, I and J) and SRC-2 (Fig. 4, N and O) protein levels were not changed in mammary LE of SRC-3(–/–) mice when compared with wild-type mice treated with chronic E2 + P4. Thus, both the loss of SRC-3 and the attendant lack of compensation by other SRC coactivators are the main reasons contributing to the reduced PR activity observed in the mammary gland of SRC-3(–/–) mice.
SRC-1, But Not SRC-3, Is Required for PR Activity in the Uterine Stroma
Previously, we reported that SRC-1 modulated PR activity in the stromal compartment of the uterus in response to chronic E2 + P4 treatment (25). To compare the role of SRC-3 in the regulation of PR activity in the uterine stroma, ovariectomized bigenic PARI-SRC-3(–/–) mice were treated with E2 + P4 for 3 d. In contrast to SRC-1(–/–) mice (Fig. 5C), there was no difference in the induction of hrGFP expression between wild type (Fig. 5, A and B) and SRC-3(–/–) mice (Fig. 5D). These data suggest that, unlike SRC-1, SRC-3 is not involved in PR-mediated transcriptional activity observed after E2 + P4 treatment in the uterine stroma (Fig. 5E).
|
). In contrast to the pattern of PR mRNA expression, mRNA levels of SRC-1, SRC-2, and SRC-3 were not changed in the uterus after E2 + P4 treatment (Fig. 6A). Although E2 + P4 treatment did not affect the expression of SRC-1, -2, or -3 mRNA, their protein levels were altered as determined by immunofluorescence staining. For example, SRC-1 protein (Fig. 6, C and E) was increased in the stroma but reduced in the LE and GE in concert with PR expression (Fig. 6, B and E). PR (Fig. 6F) colocalizes with SRC-1 (Fig. 6G) in the stroma as determined by dual immunofluorescence (Fig. 6H). Because PR and SRC-1 colocalized to the uterine stroma and shared a similar pattern of induction after E2 + P4 treatment, it supports our interpretation that PR transcriptional activity in uterine stoma is mediated through SRC-1.
|
, D and E). Therefore, a lack of SRC-3 expression in the stroma compartment of the uterus can explain our observation that deletion of SRC-3 had little effect on uterine PR activity.
Coactivator Expression Levels in the Uterus Were Changed in SRC-1(–/–) Mice, But Not in SRC- 3(–/–) Mice
Next we asked whether there was a compensatory increase or decrease of other SRCs in uterine tissue when one of them was deleted. As shown in Fig. 7A, SRC-2 expression in the uterine stroma was greatly reduced in SRC-1(–/–) mice compared with wild-type mice. The combined ablation of the SRC-1 gene and a reduced SRC-2 expression are the likely reasons for the reduced PR activity in uterine stroma in response to E2 + P4 treatment. As expected, expression levels of PR, SRC-1, and SRC-2 were not changed in the uterine stroma of SRC-3(–/–) mice as compared with the wild type (Fig. 7B). Consequently, the increased PR activity observed in the uterine stroma of SRC-3(–/–) mice was not associated with increases in PR, SRC-1, or SRC-2 expression to compensate for the loss of SRC-3. Instead, SRC-3 appears not to participate in the PR activity in the uterine stroma because it is not expressed there.
|
|
DISCUSSION |
|---|
|
TOPABSTRACTINTRODUCTIONRESULTSDISCUSSIONMATERIALS AND METHODSREFERENCES |
|---|
Both PR and SRC-1 in uterine stroma are important for the implantation response because ablation of these genes impairs the decidual response. However, until now no experiment had been performed to determine whether the PR and SRC-1 functionally interact to mediate the uterine decidual response. Our bigenic mouse model revealed that SRC-1 modulates PR activity in the uterine stroma during E2 + P4 treatment. Therefore, we conclude that SRC-1 is critical for the PR-dependent decidual response in the uterine stroma. Because the response of uterine stroma in the bigenic PRAI-SRC-3(–/–) mice to E2 + P4 treatment was unaltered, we suggest that SRC-3 does not contribute to the PR-mediated decidual response; our data are consistent with our result showing that SRC-3 is not present in the stroma compartment.
Both SRC-1(–/–) and PR(–/–) mice have defective mammary gland development. Similar defects in mammary gland development imply that SRC-1 may be involved in PR-regulated mammary gland development. However, PRAI-SRC-1(–/–) mice showed increased levels of both hrGFP (PR activity) and other endogenous PR target genes, such as Wnt-4 and Arg in the LECs of mammary tissue in response to E2 + P4. However, one of the PR-dependent gene expressions, KLF4, was partially impaired in mammary glands of SRC-1(–/–) mice. This suggests that, in addition to PR, certain other transcription factors modulated by SRC-1 could be involved in a subset of endogenous promoter activities in the mammary gland. Despite the fact that SRC-1 colocalizes with PR in LECs in response to hormonal treatment, the PR-dependent cellular response in mammary tissue is not impaired in SRC-1(–/–) mice. This observation raises a question as to why PR-dependent gene expression is not impaired in SRC-1(–/–) mice.
Our observation that SRC-1 is not required for PR activity in the mammary gland raises the question as to why SRC-1 knockout mice have defects in mammary gland development (20). One likely possibility is that SRC-1 modulates a number of other steroid receptor signaling pathways to regulate mammary gland development and that up-regulation of SRC-2 is not sufficient to compensate completely for the loss of SRC-1. In addition, ER- is known to be involved in mammary gland development, as ER-(–/–) mice had defects in both ductal and alveolar development (23). Thus, it is possible that defects in mammary gland development of SRC-1(–/–) mice are due to a requirement for SRC-1 in the function of other transcription factors such as ER-.
In contrast to SRC-1(–/–) mice, SRC-3(–/–) mice showed markedly decreased levels of both hrGFP (PR activity) and endogenous PR target gene (Wnt-4 and Arg) expression in LECs of the mammary gland in response to E2 + P4 treatment. In these mice, there were no major changes observed in the protein levels of PR or SRC-1 and SRC-2 coactivators. Therefore, the defect in mammary gland development of SRC-3(–/–) mice is likely due to direct SRC-3 coactivation of PR-dependent cellular function. Collectively, the data revealed SRC-3 to be a key coactivator modulating PR-dependent gene expression in the mammary gland.
The mouse GeneAtlas database (Mouse GeneAtlas GNF1M, MAS5 http://symatlas.gnf.org/SymAtlas/) contains the tissue-specific mRNA expression pattern of each SRC family member in mice. For example, SRC-1 mRNA was highly expressed in oocytes, and a high level of SRC-3 mRNA was detected in mammary gland and placenta. This differential tissue-specific expression of coactivators is thought to contribute to the tissue specificity of in vivo coactivator function for nuclear receptor. Our bigenic mouse system provides evidence to support this hypothesis. In the uterus, SRC-1 levels in stroma were highly induced by E2 + P4 treatment in concert with PR expression. However, the SRC-3 level was too low to be detected in this uterine compartment under the same hormonal milieu. E2 + P4 increased the ratio of SRC-1 to SRC-3 in the stroma compartment of uterus; as expected, SRC-1, but not SRC-3, modulates the PR-dependent decidual response. In addition to what we observed here for the uterus, tissue-specific differential coactivator expression patterns were shown to be important for modulating other cellular functions in vivo. Selective ER modulators modulate E2 function in certain tissues while opposing it in others. It is likely that differential expression of coactivators and corepressors is responsible for the tissue-specific agonistic or antiagonistic activity of selective ER modulators. For example, in endometrial cells (Ishkawa), tamoxifen acts as an E2 by stimulating recruitment of coactivators to a subset of genes; this does not occur in MCF-7 breast cancer cells (28). Tamoxifen appears to require the higher level of SRC-1 provided by Ishkawa cells to display agonist activity in vivo (28).
In contrast to the uterus, PR colocalized with both SRC-1 and SRC-3 in the LE of mammary gland in response to E2 + P4 treatment. Nevertheless, only SRC-3 was involved in this PR activation. Thus, it appears that in different cellular contexts, PR uses different coregulators. For example, PR preferentially interacts with SRC-1, but glucocorticoid receptor preferentially associates with SRC-2 (TIF-2/GRIP-1) on the MMTV-promoter in T-47D cells in the presence of their respective ligands (15). Studies in our laboratory as well as others indicated that external signals, such as hormones, trigger posttranslational modifications (such as phosphorylation and sumoylation) of both PR and its coactivators (29, 30, 31, 32). These external signals can be cell specific. For examples, P4 induced phosphorylation of S81 and S162 of PR through casein kinase II (29) but induced phosphorylation of S294 of PR through the MAPK signaling pathway (30, 33). SRC-3 also was phosphorylated differently in response to TNF- relative to E2 treatment (31). Differential modifications of PR and SRC-3 are likely to cause nuclear receptor and coactivator to interact differently. The final consequence of these differential modifications is differential activation of target genes and differential biological function. It is likely that such cell-specific signal transduction is a factor in determining the SRC-3 coactivator to function better than SRC-1 during mammary gland development.
|
MATERIALS AND METHODS |
|---|
|
TOPABSTRACTINTRODUCTIONRESULTSDISCUSSIONMATERIALS AND METHODSREFERENCES |
|---|
Immunofluorescence Analysis
Mice were anesthetized with Avertin and perfused through the heart with 4% paraformaldehyde in PBS. The uterus and mammary gland were removed and kept in the same fixative for 16 h at 4 C. Samples were dehydrated in ethanol, cleared in xylene, and embedded in paraffin. Sections were cut at 7 µm. For immunostaining, sections were dewaxed, rehydrated, and boiled for 10 min in 10 mM citrate buffer, pH 6.0. To reduce nonspecific binding of antibodies, sections were washed in PBS again and preincubated with 5% BSA in PBS for 1 h at room temperature. Antibodies against hrGFP (1:300; Stratagene, La Jolla, CA), PR (1:150; Santa Cruz Biotechnology, Inc., Santa Cruz, CA), SRC-1 (1:300; Santa Cruz), SRC-2 (1:500; gift from Jun Qin, Department Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX) and SRC-3 (1:300; Santa Cruz) were used to detect protein expression in tissue. After probing with primary antibodies, sections were then incubated sequentially with biotinylated horse antirabbit IgG (1:500), and Cy2- or Cy3-conjugated Avidin (1:1000; Rockland Inc., Gilbertsville, PA). To determine signal intensity in each compartment, a box was drawn through each compartment in a random orientation. The pixel intensity value of each box (in arbitrary units) was measured and a mean value was obtained. Values shown in all figures are a mean value of intensity (n = 3) ± SD. We used the fluorescence intensity after incubation with normal rabbit serum to normalize the fluorescence intensity of each compartment. The relative fluorescence intensity (RFI) is the ratio of specific antibody fluorescence intensity to normal serum fluorescence intensity for each compartment.
For double immunofluorescence, we used a double immunofluorescent procedure using two biotinylated secondary antibodies provided by Vector Laboratories (Burlingame, CA).
In Situ Hybridization
The protocol for in situ hybridization was described previously (34). hrGFP primers were 5'-GCT TGG CAT TCC GGT ACT GT-3' and 5'-GGA TCC TAA TAC GAC TCA CTA TAG GGG GTT GCC GAA CAG GAT GTT G-3'. Wnt-4 primers were 5'-CTG GAA CTG TTC CAC ACT GGA-3' and 5'-TAA TAC GAC TCA CTA TAG GGT GCT CAC AGA AGT CCG GGC TA-3'. Arg primers were 5'-TCT CCA CAG GGG ACT ACG ACT-3' and 5'-TAA TAC GAC TCA CTA TAG GGA TCT GGA ACC ATC CGA AAG CT-3'. Digoxigenin-labeled riboprobes were generated by in vitro transcription from amplified DNA products containing the T7 polymerase promoter sequence flanking the desired nucleotide primer sequence. After hybridization, sections were incubated with alkaline phosphatase-conjugated antidigoxigenin Fab fragments (Roche Molecular Biochemicals, Indianapolis, IN) diluted 1:600 in TBT (TBS, 3% BSA, 0.5% Triton X-100) for 1 h. After incubation, the slides were washed twice in TBS [50 mM Tris-HCl, 100 mM NaCl (pH 7.2)] for 5 min. The slides were then incubated in the dark for 5 h in 200 µl of a buffer containing 45 µl nitroblue tetrazolium (Roche Molecular Biochemicals) and 35 µl bromo-chloro-indolyl-phosphate (Roche Molecular Biochemicals) in 10 ml of 100 mM Tris-HCl, 100 mM NaCl, 50 mM MgCl2 (Sigma, St. Louis, MO) (pH 9.5). Color development was terminated by washing in distilled water for 5 min. The slides were counterstained with 10% methyl green, air dried, and mounted with Permount (Fisher Scientific, Pittsburgh, PA).
RT-PCR
First-strand cDNA was synthesized from total RNA using a SuperScript II RT kit (Invitrogen, Carlsbad, CA) and 250 ng of random primers according to the manufacturer’s protocol. The PCR primer pairs were as follows: 5'-GTC CCG CCA CTC ATC AAC CT-3' and 5'-GGG CAA CTG GGC AGC AAT AAC T-3' (amplified a 705-bp fragment from PR); 5'-TAA AGA TGC CGT CAC AGA TAG ATT-3' and 5'-ACC CCA GGC CAA ACA CCA T-3' (amplified a 530-bp fragment from Gal4-PR); 5'-GCT TGG CAT TCC GGT ACT GT-3' and 5'-GGT TGC CGA ACA GGA TGT TG-3' (amplified a 120-bp fragment from hrGFP); 5'-TAT TAC GAG TCC AAG GCC CA-3' and 5'-TAA GCA CAT CAC TGA AGG TGG-3' (amplified a 199-bp fragment from Indian Hedgehog); 5'-TGA ACC AGT TTG CAG CAA ATG-3' and 5'-TGT TTC CCA TTG TTC CTT GC-3' (amplified 648-bp fragment from SRC-1); 5'-AGC TCC CCT GAT GAC CTG CT-3' and 5'-AAT AGG AGC CTG AGT GGG CA-3' (amplified 520-bp fragment form SRC-2); 5'-ATG GGT CAG ATT AGC CAG CAA-3' and 5'-TCC CCT GGG GAG CAA ACT-3' (amplified 644-bp fragment from SRC-3); 5'-GTG CCC CAA GAT CAA GCA-3' and 5'-TCT TCA TGT GTA AGG CGA GGT-3' (amplified 611-bp fragment from KLF4); 5'-GCA TGG GTC GGG ACA AGA AGA-3' and 5'-CTC CAG CAG GGG GCA CCA CT-3' (amplified a 599-bp fragment from ß-Actin). The PCR products were analyzed on a 1.5% agarose gel in Tris-acetate-EDTA buffer.
|
FOOTNOTES |
|---|
First Published Online September 1, 2005
Abbreviations: Arg, Amphiregulin; E2, estrogen or 17ß-estradiol; ER, estrogen receptor; GE, glandular epithelium; hrGFP, humanized green fluorescent protein; LE, luminal epithelium; LECs, luminal epithelial cells; M, myometrium; PRAI, PR activity indicator; P4, progesterone; PR, progesterone receptor; RFI, relative fluorescence intensity; S, stroma; SRC, steroid receptor coactivator.
Received for publication July 29, 2005. Accepted for publication August 25, 2005.
|
REFERENCES |
|---|
|
TOPABSTRACTINTRODUCTIONRESULTSDISCUSSIONMATERIALS AND METHODSREFERENCES |
|---|
, 17-dioxolanes: development of high-affinity ligands for the progesterone receptor with high in vivo target site selectivity. J Med Chem 38:328–337[CrossRef][Medline]. Cancer Res 59:1869–1876NURSA Molecule Pages Link:
This article has been cited by other articles:
 |
|
 |
|
  L. Liao, X. Chen, S. Wang, A. F. Parlow, and J. Xu Steroid Receptor Coactivator 3 Maintains Circulating Insulin-Like Growth Factor I (IGF-I) by Controlling IGF-Binding Protein 3 Expression Mol. Cell. Biol., April 1, 2008; 28(7): 2460 - 2469. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. N. Miner, B. Ardecky, K. Benbatoul, K. Griffiths, C. J. Larson, D. E. Mais, K. Marschke, J. Rosen, E. Vajda, L. Zhi, et al. Antiinflammatory glucocorticoid receptor ligand with reduced side effects exhibits an altered protein protein interaction profile PNAS, December 4, 2007; 104(49): 19244 - 19249. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J.-W. Jeong, K. Y. Lee, S. J. Han, B. J. Aronow, J. P. Lydon, B. W. O'Malley, and F. J. DeMayo The p160 Steroid Receptor Coactivator 2, SRC-2, Regulates Murine Endometrial Function and Regulates Progesterone-Independent and -Dependent Gene Expression Endocrinology, September 1, 2007; 148(9): 4238 - 4250. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Schumacher, R. Guennoun, A. Ghoumari, C. Massaad, F. Robert, M. El-Etr, Y. Akwa, K. Rajkowski, and E.-E. Baulieu Novel Perspectives for Progesterone in Hormone Replacement Therapy, with Special Reference to the Nervous System Endocr. Rev., June 1, 2007; 28(4): 387 - 439. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 K. P. Madauss, E. T. Grygielko, S.-J. Deng, A. C. Sulpizio, T. B. Stanley, C. Wu, S. A. Short, S. K. Thompson, E. L. Stewart, N. J. Laping, et al. A Structural and in Vitro Characterization of Asoprisnil: A Selective Progesterone Receptor Modulator Mol. Endocrinol., May 1, 2007; 21(5): 1066 - 1081. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. J. Han, S. Y. Tsai, M.-J. Tsai, and B. W. O'Malley Distinct Temporal and Spatial Activities of RU486 on Progesterone Receptor Function in Reproductive Organs of Ovariectomized Mice Endocrinology, May 1, 2007; 148(5): 2471 - 2486. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. McMaster and D. W. Ray Modelling the glucocorticoid receptor and producing therapeutic agents with anti-inflammatory effects but reduced side-effects Exp Physiol, March 1, 2007; 92(2): 299 - 309. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. Yan, C.-T. Yu, M. Ozen, M. Ittmann, S. Y. Tsai, and M.-J. Tsai Steroid Receptor Coactivator-3 and Activator Protein-1 Coordinately Regulate the Transcription of Components of the Insulin-Like Growth Factor/AKT Signaling Pathway. Cancer Res., November 15, 2006; 66(22): 11039 - 11046. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Mukherjee, S. M. Soyal, R. Fernandez-Valdivia, M. Gehin, P. Chambon, F. J. DeMayo, J. P. Lydon, and B. W. O'Malley Steroid Receptor Coactivator 2 Is Critical for Progesterone-Dependent Uterine Function and Mammary Morphogenesis in the Mouse. Mol. Cell. Biol., September 1, 2006; 26(17): 6571 - 6583. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Georgiakaki, N. Chabbert-Buffet, B. Dasen, G. Meduri, S. Wenk, L. Rajhi, L. Amazit, A. Chauchereau, C. W. Burger, L. J. Blok, et al. Ligand-Controlled Interaction of Histone Acetyltransferase Binding to ORC-1 (HBO1) with the N-Terminal Transactivating Domain of Progesterone Receptor Induces Steroid Receptor Coactivator 1-Dependent Coactivation of Transcription Mol. Endocrinol., September 1, 2006; 20(9): 2122 - 2140. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. C. Velarde, M. Iruthayanathan, R. R. Eason, D. Zhang, F. A. Simmen, and R. C. M. Simmen Progesterone Receptor Transactivation of the Secretory Leukocyte Protease Inhibitor Gene in Ishikawa Endometrial Epithelial Cells Involves Recruitment of Kruppel-Like Factor 9/Basic Transcription Element Binding Protein-1 Endocrinology, April 1, 2006; 147(4): 1969 - 1978. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
F. A. Simmen and R. C. M. Simmen Orchestrating the Menstrual Cycle: Discerning the Music from the Noise. Endocrinology, March 1, 2006; 147(3): 1094 - 1096. [Full Text] [PDF]
|
|
| ||||||||||||||||||||
