| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
5-4 Isomerase Type 2 Promoter Is a Novel Target for the Immediate Early Orphan Nuclear Receptor Nur77 in Steroidogenic Cells
Ontogeny-Reproduction Research Unit, Centre Hospitalier de l’Université Laval (CHUL) Research Center (L.J.M., J.J.T.), Ste-Foy, Québec, Canada; and Department of Obstetrics and Gynecology, Faculty of Medicine, Université Laval (J.J.T.), Ste-Foy, Québec, Canada
Address all correspondence and requests for reprints to: Dr. Jacques J. Tremblay, Ontogeny-Reproduction, Room T1-49, CHUL Research Center, 2705 Laurier Boulevard, Ste-Foy, Québec, Canada G1V 4G2. E-mail: jacques-j.tremblay{at}crchul.ulaval.ca.
 |
Abstract |
|---|
 Top Abstract IntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
5-4 isomerase type 2 (3ß-HSD2) enzyme, encoded by the hHSD3B2 gene, is mainly found in gonads and adrenals. This enzyme catalyzes an essential early step in the biosynthesis of all classes of steroid hormones. The critical nature of the enzyme is supported by the occurrence of human syndromes that are associated with insufficient 3ß-HSD2 expression and/or activity. Although the need for a functional 3ß-HSD2 enzyme is indisputable, the molecular mechanisms that regulate HSD3B2 expression (both basal and hormone-induced) in steroidogenic cells remain poorly understood. A role for the Nur77 family of immediate-early orphan nuclear receptors in steroidogenesis has received recent interest. For example, Nur77 is present in gonads and adrenals, where its expression is robustly and rapidly induced by hormones that stimulate steroidogenic gene expression. Moreover, the expression patterns of Nur77 and at least one key steroidogenic gene (hHSD3B2) closely parallel one another. We now report that the hHSD3B2 promoter is indeed a novel target for Nur77 in both testicular Leydig cells and adrenal cells. We have mapped a novel response element located at –130 bp specific for Nur77 and not other orphan nuclear receptors (steroidogenic factor-1 and liver receptor homolog-1) previously shown to regulate hHSD3B2 promoter activity. This Nur77 element is essential and sufficient to confer Nur77 responsiveness to the hHSD3B2 promoter, and its mutation blunts basal and hormone-induced hHSD3B2 promoter activity in steroidogenic cells. We also show that Nur77 synergizes with all members of the steroid receptor coactivator family of coactivators on the hHSD3B2 promoter. Taken together, our identification of Nur77 as an important regulator of HSD3B2 promoter activity helps us to better define the tissue-specific and hormonal regulation of the HSD3B2 gene in steroidogenic cells. |
Introduction |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
5-4 isomerase type 2 (3ß-HSD2) gene, HSD3B2, is expressed in both the gonads and the adrenals and encodes the 3ß-HSD2 enzyme that is required for the initial steps of all classes of steroid hormone biosynthesis (reviewed in Ref.1). Its crucial role in steroidogenesis is underscored by the existence of human (h) HSD3B2 gene mutations that are responsible for 3ß-HSD2 deficiency. Affected individuals have congenital adrenal hyperplasia accompanied by various degrees of salt-wasting in both sexes. In addition, because 3ß-HSD2 is also required for testosterone synthesis in testicular Leydig cells, genetic males are pseudohermaphrodites with female external genitalia (1). Despite its importance for normal steroidogenesis and proper male sex differentiation, very little is known about the mechanisms that regulate expression of the hHSD3B2 gene in steroidogenic cells. HSD3B2 gene expression, however, is known to be hormonally regulated by angiotensin II (AII) and ACTH, which acts on adrenal cells, and LH/hCG, which regulates steroidogenesis in testicular Leydig cells and ovarian thecal and luteinized granulosa cells (reviewed in Ref.1). AII acts through the diacylglycerol and inositol triphosphate pathways (2), whereas ACTH and LH/hCG mediate their effects through activation of the cAMP/protein kinase A (PKA) signaling pathway. This pathway triggers at least two distinct mechanisms that are both essential for an optimal response. One does not require de novo protein synthesis; rather, it relies on phosphorylation of transcription factors already present in the cell. The other mechanism requires protein synthesis, involving rapid induction of genes encoding transcription factors (3, 4, 5, 6, 7, 8). To date, only a few transcription factors have been shown to bind and activate the hHSD3B2 promoter. These include two members of the NR5A family of orphan nuclear receptors, steroidogenic factor-1 (SF-1) (9) and liver receptor homolog-1 (LRH-1) (10), as well as the signal transducer and activator of transcription proteins 5 and 6 (11, 12, 13, 14). These transcription factors are all found in steroidogenic tissues expressing hHSD3B2 (10, 11, 15, 16, 17, 18, 19, 20, 21). However, because they are also present in other tissues that do not express HSD3B2, such as pituitary gonadotrope cells, liver, pancreas, the zona reticularis of the adrenals, and testicular Sertoli cells (22, 23, 24), other transcription factors are probably involved in tissue-specific HSD3B2 expression. Moreover, the expression of SF-1 and LRH-1 is unchanged, decreased, or only slightly increased in steroidogenic cells in response to ACTH, LH/hCG, or cAMP analogs, which indicates that they are not likely to be the rapidly induced transcription factor required for maximal hormonal stimulation (22, 25). Thus, the newly synthesized transcription factor involved in the hormone-induced up-regulation of HSD3B2 expression has yet to be identified.
Nur77, also known as NGFI-B, TR3, or NR4A1, is a member of the NR4A family of orphan nuclear receptors, which also includes Nurr1 (NR4A2) and Nor1 (NR4A3). Members of this family are immediate-early response genes, and their expression, particularly that of Nur77, is strongly and rapidly induced after various stimuli in numerous tissues (26, 27), including hormonally stimulated steroidogenic cells (28, 29, 30, 31). Nur77 can bind to DNA in three different ways: as a monomer to a Nur77-binding response element (NBRE), which is very similar to SF-1-binding sites (32); as a homo- or heterodimer to an inverted repeat response element (NurRE) (33, 34); or to a DR5 element by heterodimerization with retinoid X receptor (35). Members of the Nur77 family have been identified as important regulators of hormonally regulated gene expression in several endocrine tissues, including the pituitary (proopiomelanocortin gene) (33), the ovary (20
-HSD gene) (36), and, more recently, the adrenals (Cyp11B2 gene) (37) and testis (Cyp17 gene) (38).
We now report that the hHSD3B2 promoter is a novel target for Nur77 in both testicular Leydig cells and adrenal cells. Using detailed promoter analyses, we have identified a novel NBRE element located at –130 bp that is specifically recognized by Nur77, but not SF-1 or LRH-1. This novel NBRE element is also essential and sufficient to confer Nur77 responsiveness to the hHSD3B2 promoter. Moreover, mutation of the NBRE element blunts cAMP-mediated activation of the hHSD3B2 promoter in both Leydig and adrenal cells. Finally, we show that Nur77 synergizes with SRC coactivators (SRC-1/2/3) to further enhance hHSD3B2 promoter activity. Thus, our results provide critical new insights into the tissue-specific expression and hormonal regulation of hHSD3B2 gene transcription in steroidogenic cells.
|
Materials and Methods |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
was obtained by transferring the PKA cDNA from the MT-PKAc (42) obtained from Dr. Mark Montminy (The Salk Institute for Biological Studies, La Jolla, CA). The mouse SRC-1, SRC-2, and SRC-3 expression plasmids (43) were gifts from Dr. Joseph Torshia (University of Western Ontario, London, Canada).
Cell culture and transfections
Mouse Leydig MA-10 cells (44), provided by Dr. Mario Ascoli (University of Iowa, Iowa City, IA), were grown in Waymouth’s MB752/1 medium supplemented with 20 mM HEPES, 15% horse serum, and 50 mg/liter gentamicin, and streptomycin sulfates at 37 C in 5% CO2. Human adrenal H295R cells were obtained from American Type Culture Collection (Manassas, VA) and grown in DMEM/Ham’s F-12 (1:1) medium supplemented with 15 mM HEPES, 1.2 g/liter NaHCO3, 2.5% NuSerum, and 10 ml/liter of ITS+ Premix (BD Biosciences, San Jose, CA) at 37 C in 5% CO2. All transfections were performed in 12-well plates using the Lipofectamine 2000 method (Invitrogen Canada, Burlington, Canada) according to the manufacturer’s recommendations. Briefly, the day before transfection, MA-10 and H295R cells were plated at 200,000 and 300,000 cells/well, respectively. The next day, cells were transfected with 1.5 µg hHSD3B2 promoter construct fused to Firefly luciferase, 250 ng cytomegalovirus-driven expression vector, 10 ng phRL-TK Renilla luciferase as an internal control, and pSP64 as carrier DNA up to 2 µg/ well using 5 µl Lipofectamine 2000 and antibiotic- and serum-free medium. Five hours later, cells were provided with complete medium. The following day, the Dual Luciferase Assay System (Promega Corp., Madison, WI) was used to harvest the cells and measure luciferase activities using an EG&G Berthold LB 9507 luminometer. In experiments with cAMP stimulation, cells were treated with 0.5 mM dibutyryl cAMP [(Bu)2cAMP] for 6 h before harvesting. Several DNA preparations of the plasmids were used to ensure reproducibility of the results. The data reported represent the average of at least three experiments, each performed in duplicate.
EMSAs
Nuclear extracts were obtained from MA-10 cells treated with either vehicle or 0.5 mM (Bu)2cAMP for 4 h. Recombinant Nur77, SF-1, and LRH-1 proteins were in vitro translated using the T7 QuickCoupled TnT system (Promega Corp.). DNA binding assays were performed using either 10 µg nuclear extracts or 1–2 µl in vitro translated protein as described previously (45), with the exception of dI:dC, where 100 ng were used for EMSAs performed with in vitro translated proteins. The 32P-labeled double-stranded oligonucleotides used as probes were as follows: hHSD3B2 NBRE element (underlined) at –130 bp (sense, 5'-GATCCTAACCTAAAGGTCACTATTA-3'; antisense, 5'-GATCTAATAGTGACCTTTAGGTTAG-3'), and hHSD3B2 SF-1/LRH-1 element (underlined) at –60 bp (sense, 5'-GATCCGGAGTTCAAGGTAATAAGGA-3'; antisense, 5'-GATCTCCTTATTACCTTGAACTCCG-3'). For the competition experiments, double-stranded oligonucleotides corresponding to mutated versions of the NBRE and SF-1/LRH-1 elements were used. The sequences of the oligonucleotides are the same as those described above, except that the NBRE element (TAAAGGTCA) was mutated into TAAATTTCA, and the SF-1/LRH-1 element was changed from TCAAGGTAA to TCAATTTAA. For supershift experiments, 1.6 µg of a commercially available anti-Nur77 antiserum (M-210, Santa Cruz Biotechnology, Inc., Santa Cruz, CA) were also added to the binding reaction.
|
Results |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
, Nur77 protein levels were strongly induced in a time-dependent manner in response to (Bu)2cAMP in both MA-10 Leydig and H295R adrenal cells. These results thus raise the intriguing possibility that Nur77 could represent the hormonally induced transcription factor required for maximal stimulation of hHSD3B2 promoter in these cells. In support of this hypothesis, the hHSD3B2 promoter contains two regulatory elements (at –320 and –60 bp) for the binding of orphan nuclear receptors known to bind DNA as monomers, including SF-1 and LRH-1 (9, 10), and potentially Nur77, which we now propose (32, 41).
|
, Nur77 as well as the other Nur77 family members, Nurr1 and Nor1, found in steroidogenic tissues (29, 31) could activate a –1073 bp hHSD3B2 reporter construct (3-fold in MA-10 cells and 1.7-fold in H295R cells), whereas SF-1 and LRH-1 had no statistically significant effect (P > 0.05, by t test). This is probably due to the fact that these cells already contain significant levels of SF-1 and LRH-1 (9, 15, 46).
Localization of the Nur77-responsive element
To locate the Nur77-responsive element, 5'-progressive deletions of the hHSD3B2 promoter were generated and tested for Nur77 responsiveness in MA-10 and H295R cells (Fig. 2A). A deletion construct to –340 bp that retained the two previously characterized SF-1/LRH-1 elements (–320 and –60 bp) was still activated by Nur77. Deletion to –224 bp that removed the distal (–320 bp) SF-1/LRH-1 element had no effect on Nur77-dependent activation of the hHSD3B2 promoter. Additional deletion to –95 bp while retaining the proximal (–60 bp) SF-1/LRH-1 element, however, completely abrogated transactivation of the hHSD3B2 promoter by Nur77. Taken together, these results indicate that the two SF-1/LRH-1 elements are not required for Nur77-dependent activation of the hHSD3B2 promoter and that a novel, as yet unidentified, element located between –224 and –95 bp is responsible for Nur77 responsiveness. Indeed, sequence analysis of this promoter region revealed the presence of a consensus NBRE located at position –130 bp (Fig. 2B). The importance of this novel NBRE element in Nur77-mediated hHSD3B2 promoter activation was further analyzed by mutagenesis in the context of the –1073 bp hHSD3B2 reporter. As shown in Fig. 3A, mutation of the –130 bp NBRE element (TAAAGGTCA
TAAATTTCA) completely abolished hHSD3B2 promoter activation by Nur77 in both MA-10 and H295R cells. Mutation of the –60 bp SF-1/LRH-1 element (TCAAGGTAATCAATTTAA), however, had no effect on Nur77-dependent hHSD3B2 promoter activation. Thus, the novel NBRE element (–130 bp) is both necessary and sufficient to confer Nur77 responsiveness to the hHSD3B2 promoter.
|
|
). In unstimulated MA-10 cells, a weak band (Fig. 3B, lane 3) that comigrated with in vitro produced Nur77 (Fig. 3B, lane 2) was observed. This binding was strongly enhanced in nuclear extracts from (Bu)2cAMP-treated MA-10 cells (Fig. 3B, lane 4). Furthermore, this band was supershifted by the addition of an anti-Nur77 antiserum (Fig. 3B, lane 6). Thus, endogenous Nur77 DNA-binding activity on the novel NBRE element is strongly induced by cAMP analogs.
Specific binding of Nur77 to the NBRE element (–130 bp)
The DNA binding specificity of Nur77 to the novel NBRE element (–130 bp) was next assessed by EMSA. Consistent with the specific requirement for the NBRE element in Nur77-mediated activation of the hHSD3B2 promoter (Fig. 3A), in vitro translated Nur77 bound with high affinity to the NBRE element (Fig. 4A), but not to the proximal (–60 bp) SF-1/LRH-1 element (Fig. 4B). Nur77 binding was specifically competed by increasing doses of unlabeled oligonucleotides (Fig. 4A, lanes 7 and 8), but not by oligonucleotides harboring a mutation in the NBRE element (Fig 4A, lanes 9 and 10) or oligonucleotides corresponding to the proximal SF-1/LRH-1 element (Fig. 4A, lanes 3 and 4).
|
, C and D). This binding was completely competed by self oligonucleotides (lanes 3 and 4 in Fig. 4, C and D), but only slightly by an oligonucleotide corresponding to the NBRE (–130 bp) element even at the highest dose (lanes 7 and 8 in Fig. 4, C and D). Thus, these results indicate that the Nur77 and SF-1/LRH-1 orphan nuclear receptors each have their specific binding sites within the hHSD3B2 promoter, raising the possibility that they might cooperate to regulate hHSD3B2 promoter activity. However, as shown in Fig. 5, no transcriptional cooperation was observed among the three orphan nuclear receptors. Rather, coexpression of Nur77 and SF-1 (but not LRH-1) resulted in a loss of Nur77-dependent hHSD3B2 promoter activation, specifically in MA-10 cells. Although the underlying reasons behind this effect remain unknown, this might be due to limiting amounts of an additional coactivator common to both SF-1 and Nur77 in MA-10, but not H295R, cells.
|
, activation of the hHSD3B2 promoter mediated by Nur77 overexpression was similar to the activation induced by (Bu)2cAMP. The combination of Nur77 and (Bu)2cAMP produced an additive effect (Fig. 6A). These results suggest that Nur77 and other cAMP-regulated transcription factors might function in a linear or parallel pathway to regulate hHSD3B2 promoter activity in steroidogenic cells.
|
, mutation of the –130 bp NBRE led to a 40% decrease in cAMP responsiveness compared with the wild-type promoter (from 3- to 1.8-fold stimulation), whereas a 24% decrease (from 3- to 2.3-fold stimulation) was observed when the –60 bp SF-1/LRH-1 element was mutated. Mutation of both elements led to no further decrease compared with the NBRE mutation alone. The results of the mutation experiments, summarized in Table 1, indicate that the Nur77/NBRE complex is a more important contributor to the cAMP responsiveness of the hHSD3B2 promoter than is the proximal SF-1/LRH-1 element. They also indicate that although an intact NBRE element is necessary for maximal stimulation, additional regulatory elements/transcription factors contribute to the cAMP regulation of the hHSD3B2 promoter.
|
), combination of these coactivators with Nur77 resulted in a synergistic activation (average of 6-fold compared with 3.1 for Nur77 alone) of the –1073 bp hHSD3B2 reporter. In addition, PKA-mediated protein phosphorylation enhanced this synergy to nearly 9-fold (Fig. 7), which is consistent with previous findings that coactivator recruitment and interaction with Nur77 can be enhanced by cAMP/PKA (48). Thus, our results indicate that Nur77-dependent activation of hHSD3B2 promoter probably involves coactivator recruitment that is enhanced by the cAMP/PKA pathway.
|
|
Discussion |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
-HSD, Cyp17, Cyp11B2, and Cyp21) (36, 37, 38, 51). In this study we have identified the promoter of the 3ß-HSD gene, encoding a key enzyme essential for the synthesis of all classes of steroids, as a novel target for Nur77.
The hHSD3B2 promoter is a novel target for Nur77 in steroidogenic tissues
The HSD3B2 gene is expressed in the testis, ovary, and adrenals, and its expression within these tissues is cell and zone specific. Indeed, HSD3B2 is expressed in testicular Leydig cells, in ovarian thecal and luteinized granulosa cells, and in cells of the zona glomerulosa and fasciculata (but not reticularis) of the adrenals (reviewed in Ref.1). Therefore, transcription factors regulating the tissue-, cell-, and zone-specific expression of HSD3B2 are also likely to have a similar expression pattern. The transcription factors currently known to regulate hHSD3B2 promoter activity, however, cannot by themselves explain its highly specific expression pattern. In contrast, the Nur77 expression pattern does fulfill this criterion. Within the adrenals, Nur77 expression is zone specific like HSD3B2; it is predominantly expressed in the zona glomerulosa and fasciculata, but not in the zona reticularis (52). Nur77 is also coexpressed with hHSD3B2 in testicular Leydig cells (28) and in ovarian thecal and luteinized granulosa cells (30, 31). Taken together, these data point to a role for Nur77 in hHSD3B2 transcription. In agreement with this, we have now identified the hHSD3B2 promoter as a target for Nur77 in both Leydig and adrenal cells. Similar findings were recently reported by Bassett et al. (53). Furthermore, recent studies by Hong et al. revealed that Nur77 could activate the promoter of the mouse HSD3B1 gene, the mouse ortholog of the human HSD3B2 gene (47). The lack of a steroidogenic phenotype in Nur77–/– mice, however, would suggest otherwise (54). This can be explained by the fact that another Nur77 family member, Nurr1, was up-regulated in Nur77–/– mice, suggesting that the various Nur77 family members may compensate for one another in vivo (54). Consistent with this, Nurr1 is expressed in steroidogenic tissues (29, 31), and we have shown that it can activate the hHSD3B2 promoter as well as Nur77 (Fig. 1B).
Nur77 is known to bind as a monomer to DNA elements highly related to those recognized by the orphan nuclear receptors SF-1 and LRH-1 (32). Although the hHSD3B2 promoter contains two binding sites for SF-1 and LRH-1 located at –320 and –60 bp (9, 10), we found that Nur77-dependent activation of the hHSD3B2 promoter did not require any of these elements. Rather, Nur77 activates hHSD3B2 transcription through a novel element, located at –130 bp, that can be specifically bound by Nur77 and not SF-1 or LRH-1. This element is indeed necessary and sufficient to confer Nur77 responsivenes to the hHSD3B2 promoter in steroidogenic cells. Furthermore, mutation of this element led to a decrease of about 35% in basal hHSD3B2 promoter activity in Nur77-expressing MA-10 Leydig and H295R adrenal cells. Mutation of the –60 bp SF-1/LRH-1 element, however, resulted in a drop of more than 80% in basal hHSD3B2 promoter activity in these same cells, clearly indicating that SF-1 and/or LRH-1 are truly important regulators of basal HSD3B2 transcription. The fact that Nur77 and SF-1/LRH-1 mediate their effects through specific regulatory elements, such as on the hHSD3B2 promoter described in the present study, would be consistent with the nonredundant, yet complementary, roles played by these orphan nuclear receptors in endocrine development and function (22, 24, 26).
Roles of orphan nuclear receptors in basal and hormone-induced HSD3B2 expression
Of the three orphan nuclear receptors now known to be implicated in basal hHSD3B2 transcription (Nur77, SF-1, and LRH-1), Nur77 appears to be the most sensitive to hormonal regulation. Thus, although SF-1 and LRH-1 expression is either unaffected, decreased, or only slightly increased in response to hormones (LH/hCG, ACTH, and AII) that regulate steroidogenesis (18, 25, 50, 52, 55, 56), Nur77 expression, in contrast, is known to be strongly and rapidly induced (reviewed in Ref.26). This is not surprising given that Nur77 is an immediate-early response factor. Like 3ß-HSD, Nur77 expression is robustly induced after hormonal stimulation in the three major steroidogenic tissues; it is strongly induced by LH/hCG in granulosa cells (30, 31), by LH/cAMP in testicular Leydig cells (28), and by both ACTH/cAMP and AII in adrenal cells (29, 50, 51, 52). Therefore, the Nur77 expression pattern and its hormonal regulation in steroidogenic tissues are consistent with a role for this transcription factor in hormone-induced 3ß-HSD expression. Indeed, our cAMP regulation data and transcriptional cooperation with the SRC coactivators support such a role. By consolidating our results with those taken from the literature, we present a model (Fig. 8) in which the orphan nuclear receptors Nur77, SF-1, and LRH-1 can be integrated as nonredundant, yet complementary, regulators for the tissue-, zone-, and cell-specific and hormone-dependent expression of the hHSD3B2 gene.
|
|
Acknowledgments |
|---|
|
Footnotes |
|---|
First Published Online October 21, 2004
Abbreviations: AII, Angiotensin II; (Bu)2cAMP, dibutyryl cAMP; h, human; 3ß-HSD2, 3ß-hydroxysteroid dehydrogenase/5-4 isomerase type 2; LRH-1, liver receptor homolog-1; NBRE, Nur77-binding response element; PKA, protein kinase A; SF-1, steroidogenic factor-1; SRC, steroid receptor coactivator.
Received July 7, 2004.
Accepted for publication October 15, 2004.
|
References |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
5-4 isomerase gene family. Endocr Rev, in press
5–3ß-hydroxysteroid dehydrogenase-isomerase activity in rat adrenocortical cells by corticotropin. Endocrinology 111:427–4335–4-isomerase expression by adrenocorticotropin in bovine adrenocortical cells. Endocrinology 128:139–1455–4-isomerase: regulation by luteinizing hormone and forskolin in Leydig cells of adult rats. Endocrinology 130:2007–20155-4-isomerase, 17-hydroxylase/C17–20 lyase cytochrome P450, and cholesterol side-chain cleavage cytochrome P450 messenger ribonucleic acid levels in primary cultures of mouse Leydig cells. Endocrinology 129:1429–14355-4 isomerase promoter by the transcription factor steroidogenic factor-1/adrenal 4-binding protein and phorbol ester. J Biol Chem 272:7960–79675-4 isomerase gene: activation by prolactin. Mol Endocrinol 13:1084–10935-4 isomerase gene. J Steroid Biochem Mol Biol 82:55–63[CrossRef][Medline]
5-4-isomerase expression in human adrenocortical carcinoma cells: evidence for a Stat5-dependent mechanism. Endocrinology 144:1847–1853-induced expression of 20-hydroxysteroid dehydrogenase involves the transcription factor NUR77. J Biol Chem 275:37202–372111-fetoprotein locus is activated by a nuclear receptor of the Drosophila FTZ-F1 family. Mol Cell Biol 16:3853–3865[Abstract]
. Mol Cell Biol 24:2593–2604This article has been cited by other articles:
 |
|
 |
|
  P. R. Manna, I. T. Huhtaniemi, and D. M. Stocco Mechanisms of Protein Kinase C Signaling in the Modulation of 3',5'-Cyclic Adenosine Monophosphate-Mediated Steroidogenesis in Mouse Gonadal Cells Endocrinology, July 1, 2009; 150(7): 3308 - 3317. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 L. J Martin and J. J Tremblay The nuclear receptors NUR77 and SF1 play additive roles with c-JUN through distinct elements on the mouse Star promoter J. Mol. Endocrinol., February 1, 2009; 42(2): 119 - 129. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
B. El-Asmar, X. C Giner, and J. J Tremblay Transcriptional cooperation between NF-{kappa}B p50 and CCAAT/enhancer binding protein {beta} regulates Nur77 transcription in Leydig cells J. Mol. Endocrinol., February 1, 2009; 42(2): 131 - 138. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. R. Manna, M. T. Dyson, Y. Jo, and D. M. Stocco Role of Dosage-Sensitive Sex Reversal, Adrenal Hypoplasia Congenita, Critical Region on the X Chromosome, Gene 1 in Protein Kinase A- and Protein Kinase C-Mediated Regulation of the Steroidogenic Acute Regulatory Protein Expression in Mouse Leydig Tumor Cells: Mechanism of Action Endocrinology, January 1, 2009; 150(1): 187 - 199. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. A. L. Bayne, T. Forster, S. T. G. Burgess, M. Craigon, M. J. Walton, D. T. Baird, P. Ghazal, and R. A. Anderson Molecular Profiling of the Human Testis Reveals Stringent Pathway-Specific Regulation of RNA Expression Following Gonadotropin Suppression and Progestogen Treatment J Androl, July 1, 2008; 29(4): 389 - 403. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 D. G. Romero, M. W. Plonczynski, B. L. Welsh, C. E. Gomez-Sanchez, M. Y. Zhou, and E. P. Gomez-Sanchez Gene expression profile in rat adrenal zona glomerulosa cells stimulated with aldosterone secretagogues Physiol Genomics, December 19, 2007; 32(1): 117 - 127. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. G. Romero, S. Rilli, M. W. Plonczynski, L. L. Yanes, M. Y. Zhou, E. P. Gomez-Sanchez, and C. E. Gomez-Sanchez Adrenal transcription regulatory genes modulated by angiotensin II and their role in steroidogenesis Physiol Genomics, June 19, 2007; 30(1): 26 - 34. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. A. Allen, T. Shankara, P. Janus, S. Buck, T. Diemer, K. Held Hales, and D. B. Hales Energized, Polarized, and Actively Respiring Mitochondria Are Required for Acute Leydig Cell Steroidogenesis Endocrinology, August 1, 2006; 147(8): 3924 - 3935. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 N. M. Robert, L. J. Martin, and J. J. Tremblay The Orphan Nuclear Receptor NR4A1 Regulates Insulin-Like 3 Gene Transcription in Leydig Cells Biol Reprod, February 1, 2006; 74(2): 322 - 330. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. F. Bouchard, H. Taniguchi, and R. S. Viger Protein Kinase A-Dependent Synergism between GATA Factors and the Nuclear Receptor, Liver Receptor Homolog-1, Regulates Human Aromatase (CYP19) PII Promoter Activity in Breast Cancer Cells Endocrinology, November 1, 2005; 146(11): 4905 - 4916. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 L. J. Martin, H. Taniguchi, N. M. Robert, J. Simard, J. J. Tremblay, and R. S. Viger GATA Factors and the Nuclear Receptors, Steroidogenic Factor 1/Liver Receptor Homolog 1, Are Key Mutual Partners in the Regulation of the Human 3{beta}-Hydroxysteroid Dehydrogenase Type 2 Promoter Mol. Endocrinol., September 1, 2005; 19(9): 2358 - 2370. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. Simard, M.-L. Ricketts, S. Gingras, P. Soucy, F. A. Feltus, and M. H. Melner Molecular Biology of the 3{beta}-Hydroxysteroid Dehydrogenase/{Delta}5-{Delta}4 Isomerase Gene Family Endocr. Rev., June 1, 2005; 26(4): 525 - 582. [Abstract] [Full Text] [PDF]
|
|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Endocrinology | Endocrine Reviews | J. Clin. End. & Metab. |
| Molecular Endocrinology | Recent Prog. Horm. Res. | All Endocrine Journals |
) or expression vectors (250 ng) for Nur77 family members (
), SF-1 (
), and LRH-1 (
) as indicated. The positions of the two previously characterized binding sites for orphan nuclear receptors within the –1073 to +53 bp hHSD3B2 promoter fragment (–320 and –60 bp) are represented by triangles. Results are shown as fold activation over the control value (±SEM).
; molar excesses of 2- and 5-fold) of unlabeled oligonucleotides corresponding to the wild-type –60 bp element (–60 wt), the –60 bp element mutated (underlined) from TCAAGGTAA to TCAATTTAA (–60 mut), the wild-type –130 bp element (–130 wt), and the –130 bp element containing a mutation (underlined) in the NBRE element (TAAAGGTCA
) a), in the absence or presence of an expression vector encoding the PKA catalytic subunit 