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Wang J, Huang Y, Zhang C, Ruan Y, Tian Y, Wang F, Xu Y, Yu M, Wang J, Cheng Y, Liu L, Yang R, Wang J, Yang Y, Xiong J, Hu Y, Jian R, Ni B, Wu W, Zhang J. Identification and Functional Evaluation of Alternative Splice Variants of Dax1 in Mouse Embryonic Stem Cells. Stem Cells Dev 2023; 32:554-564. [PMID: 37261981 DOI: 10.1089/scd.2023.0037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023] Open
Abstract
Dax1 (Nr0b1; Dosage-sensitive sex reversal-adrenal hypoplasia congenital on the X-chromosome gene-1) is an important component of the transcription factor network that governs pluripotency in mouse embryonic stem cells (ESCs). Functional evaluation of alternative splice variants of pluripotent transcription factors has shed additional insight on the maintenance of ESC pluripotency and self-renewal. Dax1 splice variants have not been identified and characterized in mouse ESCs. We identified 18 new transcripts of Dax1 with putative protein-coding properties and compared their protein structures with known Dax1 protein (Dax1-472). The expression pattern analysis showed that the novel isoforms were cotranscribed with Dax1-472 in mouse ESCs, but they had transcriptional heterogeneity among single cells and the subcellular localization of the encoded proteins differed. Cell function experiments indicated that Dax1-404 repressed Gata6 transcription and functionally replaced Dax1-472, while Dax1-38 and Dax1-225 partially antagonized Dax1-472 transcriptional repression. This study provided a comprehensive characterization of the Dax1 splice variants in mouse ESCs and suggested complex effects of Dax1 variants in a self-renewal regulatory network.
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Affiliation(s)
- Jiaqi Wang
- Laboratory of Stem Cell and Developmental Biology, Department of Histology and Embryology, College of Basic Medical Science, Army Medical University, Chongqing, China
- Department of Pathophysiology, College of High-Altitude Military Medicine, Army Medical University, Chongqing, China
| | - Yi Huang
- Biomedical Analysis Center, Army Medical University, Chongqing, China
| | - Chen Zhang
- Laboratory of Stem Cell and Developmental Biology, Department of Histology and Embryology, College of Basic Medical Science, Army Medical University, Chongqing, China
| | - Yan Ruan
- Laboratory of Stem Cell and Developmental Biology, Department of Histology and Embryology, College of Basic Medical Science, Army Medical University, Chongqing, China
| | - Yanping Tian
- Laboratory of Stem Cell and Developmental Biology, Department of Histology and Embryology, College of Basic Medical Science, Army Medical University, Chongqing, China
| | - Fengsheng Wang
- Laboratory of Stem Cell and Developmental Biology, Department of Histology and Embryology, College of Basic Medical Science, Army Medical University, Chongqing, China
- State Key Laboratory of NBC Protection for Civilian, Beijing, China
| | - Yixiao Xu
- Laboratory of Stem Cell and Developmental Biology, Department of Histology and Embryology, College of Basic Medical Science, Army Medical University, Chongqing, China
| | - Meng Yu
- Laboratory of Stem Cell and Developmental Biology, Department of Histology and Embryology, College of Basic Medical Science, Army Medical University, Chongqing, China
- Department of Joint Surgery, Southwest Hospital, The First Hospital Affiliated to Army Medical University, Chongqing, China
| | - Jiangjun Wang
- Laboratory of Stem Cell and Developmental Biology, Department of Histology and Embryology, College of Basic Medical Science, Army Medical University, Chongqing, China
- Department of Cell Biology, College of Basic Medical Science, Army Medical University, Chongqing, China
| | - Yuda Cheng
- Laboratory of Stem Cell and Developmental Biology, Department of Histology and Embryology, College of Basic Medical Science, Army Medical University, Chongqing, China
| | - Lianlian Liu
- Laboratory of Stem Cell and Developmental Biology, Department of Histology and Embryology, College of Basic Medical Science, Army Medical University, Chongqing, China
| | - Ran Yang
- Laboratory of Stem Cell and Developmental Biology, Department of Histology and Embryology, College of Basic Medical Science, Army Medical University, Chongqing, China
- Department of Pathophysiology, College of High-Altitude Military Medicine, Army Medical University, Chongqing, China
| | - Jiali Wang
- Laboratory of Stem Cell and Developmental Biology, Department of Histology and Embryology, College of Basic Medical Science, Army Medical University, Chongqing, China
| | - Yi Yang
- Experimental Center of Basic Medicine, College of Basic Medical Science, Army Medical University, Chongqing, China
| | - Jiaxiang Xiong
- Experimental Center of Basic Medicine, College of Basic Medical Science, Army Medical University, Chongqing, China
| | - Yan Hu
- Department of Military Basic Training and Army Management, Army Health Service Training Base, Army Medical University, Chongqing, China
| | - Rui Jian
- Laboratory of Stem Cell and Developmental Biology, Department of Histology and Embryology, College of Basic Medical Science, Army Medical University, Chongqing, China
| | - Bing Ni
- Department of Pathophysiology, College of High-Altitude Military Medicine, Army Medical University, Chongqing, China
| | - Wei Wu
- Department of Department of Thoracic Surgery, Southwest Hospital, The First Hospital Affiliated to Army Medical University, Chongqing, China
| | - Junlei Zhang
- Laboratory of Stem Cell and Developmental Biology, Department of Histology and Embryology, College of Basic Medical Science, Army Medical University, Chongqing, China
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de Mattos K, Viger RS, Tremblay JJ. Transcription Factors in the Regulation of Leydig Cell Gene Expression and Function. Front Endocrinol (Lausanne) 2022; 13:881309. [PMID: 35464056 PMCID: PMC9022205 DOI: 10.3389/fendo.2022.881309] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Accepted: 03/15/2022] [Indexed: 12/28/2022] Open
Abstract
Cell differentiation and acquisition of specialized functions are inherent steps in events that lead to normal tissue development and function. These processes require accurate temporal, tissue, and cell-specific activation or repression of gene transcription. This is achieved by complex interactions between transcription factors that form a unique combinatorial code in each specialized cell type and in response to different physiological signals. Transcription factors typically act by binding to short, nucleotide-specific DNA sequences located in the promoter region of target genes. In males, Leydig cells play a crucial role in sex differentiation, health, and reproductive function from embryonic life to adulthood. To better understand the molecular mechanisms regulating Leydig cell differentiation and function, several transcription factors important to Leydig cells have been identified, including some previously unknown to this specialized cell type. This mini review summarizes the current knowledge on transcription factors in fetal and adult Leydig cells, describing their roles and mechanisms of action.
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Affiliation(s)
- Karine de Mattos
- Reproduction, Mother and Child Health, Centre de recherche du centre hospitalier universitaire de Québec, Université Laval, Québec City, QC, Canada
| | - Robert S. Viger
- Reproduction, Mother and Child Health, Centre de recherche du centre hospitalier universitaire de Québec, Université Laval, Québec City, QC, Canada
- Centre de recherche en Reproduction, Développement et Santé Intergénérationnelle, Department of Obstetrics, Gynecology, and Reproduction, Faculty of Medicine, Université Laval, Québec City, QC, Canada
| | - Jacques J. Tremblay
- Reproduction, Mother and Child Health, Centre de recherche du centre hospitalier universitaire de Québec, Université Laval, Québec City, QC, Canada
- Centre de recherche en Reproduction, Développement et Santé Intergénérationnelle, Department of Obstetrics, Gynecology, and Reproduction, Faculty of Medicine, Université Laval, Québec City, QC, Canada
- *Correspondence: Jacques J. Tremblay,
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Ramos L, Mares L. Hamster DAX1: Molecular insights, specific expression, and its role in the Harderian gland. Comp Biochem Physiol A Mol Integr Physiol 2021; 263:111096. [PMID: 34653610 DOI: 10.1016/j.cbpa.2021.111096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 10/08/2021] [Accepted: 10/08/2021] [Indexed: 10/20/2022]
Abstract
DAX1 plays an essential role in the differentiation and physiology of the Hypothalamic-Pituitary-Adrenal-Gonadal (HPAG) axis during embryogenesis. However, in adult tissues, in addition to the HPAG axis, evidence has not been found for its differential expression and function. We isolated the DAX1 cDNA to analyze its tissue localization and gene expression profiles in male and female hamsters' Harderian glands (HGs), Mesocricetus auratus. The isolated cDNA clone contains 1848 base pairs (bp), and a 1428-bp open reading frame (ORF) encodes a 476 amino acid protein. Sequence alignments and the phylogenetic tree display a relevant percentage of similarity with human (66%), rat (81%), and mouse (84%) sequences. In adult tissues, the mRNA distribution demonstrated that DAX1 is present in testis, ovaries, and male and female HGs. The highest expression profiles were identified in the adrenal glands, where females exhibit higher mRNA levels than males. The sexually dimorphic expression of DAX1 in adrenals suggests that its presence could be associated with regulating, functioning, and maintaining this endocrine tissue. These findings indicate that the DAX1 gene is limitedly expressed in adult tissues. In the HGs, we demonstrate the absence of sexually dimorphic gene expression. Our results suggest that DAX1 might have an additional physiological function outside of the HPAG axis, specifically in the HG, which may be required for the regulation of intracrine steroidogenesis, secretion, and maintenance of exocrine tissue.
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Affiliation(s)
- L Ramos
- Department of Reproductive Biology, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, México City, Mexico.
| | - L Mares
- Department of Reproductive Biology, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, México City, Mexico
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Yan YL, Batzel P, Titus T, Sydes J, Desvignes T, BreMiller R, Draper B, Postlethwait JH. A Hormone That Lost Its Receptor: Anti-Müllerian Hormone (AMH) in Zebrafish Gonad Development and Sex Determination. Genetics 2019; 213:529-553. [PMID: 31399485 PMCID: PMC6781894 DOI: 10.1534/genetics.119.302365] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Accepted: 08/04/2019] [Indexed: 12/26/2022] Open
Abstract
Fetal mammalian testes secrete Anti-Müllerian hormone (Amh), which inhibits female reproductive tract (Müllerian duct) development. Amh also derives from mature mammalian ovarian follicles, which marks oocyte reserve and characterizes polycystic ovarian syndrome. Zebrafish (Danio rerio) lacks Müllerian ducts and the Amh receptor gene amhr2 but, curiously, retains amh To discover the roles of Amh in the absence of Müllerian ducts and the ancestral receptor gene, we made amh null alleles in zebrafish. Results showed that normal amh prevents female-biased sex ratios. Adult male amh mutants had enormous testes, half of which contained immature oocytes, demonstrating that Amh regulates male germ cell accumulation and inhibits oocyte development or survival. Mutant males formed sperm ducts and some produced a few offspring. Young female mutants laid a few fertile eggs, so they also had functional sex ducts. Older amh mutants accumulated nonvitellogenic follicles in exceedingly large but sterile ovaries, showing that Amh helps control ovarian follicle maturation and proliferation. RNA-sequencing data partitioned juveniles at 21 days postfertilization (dpf) into two groups that each contained mutant and wild-type fish. Group21-1 upregulated ovary genes compared to Group21-2, which were likely developing as males. By 35 dpf, transcriptomes distinguished males from females and, within each sex, mutants from wild types. In adult mutants, ovaries greatly underexpressed granulosa and theca genes, and testes underexpressed Leydig cell genes. These results show that ancestral Amh functions included development of the gonadal soma in ovaries and testes and regulation of gamete proliferation and maturation. A major gap in our understanding is the identity of the gene encoding a zebrafish Amh receptor; we show here that the loss of amhr2 is associated with the breakpoint of a chromosome rearrangement shared among cyprinid fishes.
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Affiliation(s)
- Yi-Lin Yan
- Institute of Neuroscience, University of Oregon, Eugene, Oregon 97403
| | - Peter Batzel
- Institute of Neuroscience, University of Oregon, Eugene, Oregon 97403
| | - Tom Titus
- Institute of Neuroscience, University of Oregon, Eugene, Oregon 97403
| | - Jason Sydes
- Institute of Neuroscience, University of Oregon, Eugene, Oregon 97403
| | - Thomas Desvignes
- Institute of Neuroscience, University of Oregon, Eugene, Oregon 97403
| | - Ruth BreMiller
- Institute of Neuroscience, University of Oregon, Eugene, Oregon 97403
| | - Bruce Draper
- Department of Molecular and Cellular Biology, University of California, Davis, California 95616
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Qian H, He P, Lv F, Wu W. Genome-wide analysis of LXXLL-mediated DAX1/SHP–nuclear receptor interaction network and rational design of stapled LXXLL-based peptides to target the specific network profile. Int J Biol Macromol 2019; 129:13-22. [DOI: 10.1016/j.ijbiomac.2019.02.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2018] [Revised: 02/02/2019] [Accepted: 02/02/2019] [Indexed: 01/22/2023]
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Mathew SP, Thakur K, Kumar S, Yende AS, Singh SK, Dash AK, Tyagi RK. A Comprehensive Analysis and Prediction of Sub-Cellular Localization of Human Nuclear Receptors. NUCLEAR RECEPTOR RESEARCH 2018. [DOI: 10.11131/2018/101324] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Orekhova AS, Rubtsov PM. DAX1, an unusual member of the nuclear receptor superfamily with diverse functions. Mol Biol 2015. [DOI: 10.1134/s0026893315010124] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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The signaling phospholipid PIP3 creates a new interaction surface on the nuclear receptor SF-1. Proc Natl Acad Sci U S A 2014; 111:15054-9. [PMID: 25288771 DOI: 10.1073/pnas.1416740111] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The signaling phosphatidylinositol lipids PI(4,5)P2 (PIP2) and PI(3,4,5)P3 (PIP3) bind nuclear receptor 5A family (NR5As), but their regulatory mechanisms remain unknown. Here, the crystal structures of human NR5A1 (steroidogenic factor-1, SF-1) ligand binding domain (LBD) bound to PIP2 and PIP3 show the lipid hydrophobic tails sequestered in the hormone pocket, as predicted. However, unlike classic nuclear receptor hormones, the phosphoinositide head groups are fully solvent-exposed and complete the LBD fold by organizing the receptor architecture at the hormone pocket entrance. The highest affinity phosphoinositide ligand PIP3 stabilizes the coactivator binding groove and increases coactivator peptide recruitment. This receptor-ligand topology defines a previously unidentified regulatory protein-lipid surface on SF-1 with the phosphoinositide head group at its nexus and poised to interact with other proteins. This surface on SF-1 coincides with the predicted binding site of the corepressor DAX-1 (dosage-sensitive sex reversal, adrenal hypoplasia critical region on chromosome X), and importantly harbors missense mutations associated with human endocrine disorders. Our data provide the structural basis for this poorly understood cluster of human SF-1 mutations and demonstrates how signaling phosphoinositides function as regulatory ligands for NR5As.
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Role of Orphan Nuclear Receptor DAX-1/NR0B1 in Development, Physiology, and Disease. ACTA ACUST UNITED AC 2014. [DOI: 10.1155/2014/582749] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
DAX-1/NR0B1 is an unusual orphan receptor that has a pivotal role in the development and function of steroidogenic tissues and of the reproductive axis. Recent studies have also indicated that this transcription factor has an important function in stem cell biology and in several types of cancer. Here I critically review the most important findings on the role of DAX-1 in development, physiology, and disease of endocrine tissues since the cloning of its gene twenty years ago.
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DAX1 regulatory networks unveil conserved and potentially new functions. Gene 2013; 530:66-74. [PMID: 23954228 DOI: 10.1016/j.gene.2013.07.052] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2013] [Accepted: 07/09/2013] [Indexed: 11/22/2022]
Abstract
DAX1 is an orphan nuclear receptor with actions in mammalian sex determination, regulation of steroidogenesis, embryonic development and neural differentiation. Conserved patterns of DAX1 gene expression from mammals to fish have been taken to suggest conserved function. In the present study, the European sea bass, Dicentrarchus labrax, DAX1 promoter was isolated and its conserved features compared to other fish and mammalian DAX1 promoters in order to derive common regulators and functional gene networks. Fish and mammalian DAX1 promoters share common sets of transcription factor frameworks which were also present in the promoter region of another 127 genes. Pathway analysis clustered these into candidate gene networks associated with the fish and mammalian DAX1. The networks identified are concordant with described functions for DAX1 in embryogenesis, regulation of transcription, endocrine development and steroid production. Novel candidate gene network partners were also identified, which implicate DAX1 in ion homeostasis and transport, lipid transport and skeletal development. Experimental evidence is provided supporting roles for DAX1 in steroid signalling and osmoregulation in fish. These results highlight the usefulness of the in silico comparative approach to analyse gene regulation for hypothesis generation. Conserved promoter architecture can be used also to predict potentially new gene functions. The approach reported can be applied to genes from model and non-model species.
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A pleiotropic role for the orphan nuclear receptor small heterodimer partner in lipid homeostasis and metabolic pathways. J Lipids 2012; 2012:304292. [PMID: 22577560 PMCID: PMC3346990 DOI: 10.1155/2012/304292] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2011] [Accepted: 12/05/2011] [Indexed: 12/29/2022] Open
Abstract
Nuclear receptors (NRs) comprise one of the most abundant classes of transcriptional regulators of metabolic diseases and have emerged as promising pharmaceutical targets. Small heterodimer partner (SHP; NR0B2) is a unique orphan NR lacking a DNA-binding domain but contains a putative ligand-binding domain. SHP is a transcriptional regulator affecting multiple key biological functions and metabolic processes including cholesterol, bile acid, and fatty acid metabolism, as well as reproductive biology and glucose-energy homeostasis. About half of all mammalian NRs and several transcriptional coregulators can interact with SHP. The SHP-mediated repression of target transcription factors includes at least three mechanisms including direct interference with the C-terminal activation function 2 (AF2) coactivator domains of NRs, recruitment of corepressors, or direct interaction with the surface of NR/transcription factors. Future research must focus on synthetic ligands acting on SHP as a potential therapeutic target in a series of metabolic abnormalities. Current understanding about the pleiotropic role of SHP is examined in this paper, and principal metabolic aspects connected with SHP function will be also discussed.
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Lardone MC, Parada-Bustamante A, Ebensperger M, Valdevenito R, Kakarieka E, Martinez D, Pommer R, Piottante A, Castro A. DAX-1 and DAX-1A expression in human testicular tissues with primary spermatogenic failure. Mol Hum Reprod 2011; 17:739-46. [DOI: 10.1093/molehr/gar051] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Zhang Y, Hagedorn CH, Wang L. Role of nuclear receptor SHP in metabolism and cancer. Biochim Biophys Acta Mol Basis Dis 2010; 1812:893-908. [PMID: 20970497 DOI: 10.1016/j.bbadis.2010.10.006] [Citation(s) in RCA: 178] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2010] [Revised: 10/12/2010] [Accepted: 10/14/2010] [Indexed: 02/07/2023]
Abstract
Small heterodimer partner (SHP, NR0B2) is a unique member of the nuclear receptor (NR) superfamily that contains the dimerization and ligand-binding domain found in other family members, but lacks the conserved DNA-binding domain. The ability of SHP to bind directly to multiple NRs is crucial for its physiological function as a transcriptional inhibitor of gene expression. A wide variety of interacting partners for SHP have been identified, indicating the potential for SHP to regulate an array of genes in different biological pathways. In this review, we summarize studies concerning the structure and target genes of SHP and discuss recent progress in understanding the function of SHP in bile acid, cholesterol, triglyceride, glucose, and drug metabolism. In addition, we review the regulatory role of SHP in microRNA (miRNA) regulation, liver fibrosis and cancer progression. The fact that SHP controls a complex set of genes in multiple metabolic pathways suggests the intriguing possibility of developing new therapeutics for metabolic diseases, including fatty liver, dyslipidemia and obesity, by regulating SHP with small molecules. To achieve this goal, more progress regarding SHP ligands and protein structure will be required. Besides its metabolic regulatory function, studies by us and other groups provide strong evidence that SHP plays a critical role in the development of cancer, particularly liver and breast cancer. An increased understanding of the fundamental mechanisms by which SHP regulates the development of cancers will be critical in applying knowledge of SHP in diagnostic, therapeutic or preventive strategies for specific cancers. This article is part of a Special Issue entitled: Translating nuclear receptors from health to disease.
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Affiliation(s)
- Yuxia Zhang
- Department of Medicine, Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, UT 84132, USA
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Pan ZQ, Fang ZQ, Lu WL, Liu XM, Guan DY, Liang C. [Differential gene expressions of steroid- and catecholamine-synthesizing enzymes in adrenal gland of rats with different diseases but the same syndromes]. ACTA ACUST UNITED AC 2010; 8:352-7. [PMID: 20388476 DOI: 10.3736/jcim20100409] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE To study the gene expression characteristics of steroid- and catecholamine-synthesizing enzymes in adrenal gland of spontaneously hypertensive rats (SHRs), Goto-Kakizaki (GK) rats and normal Wistar rats with the same traditional Chinese medicine syndromes. METHODS Sixteen-week-old Wistar rats, SHRs and GK rats were used. By the quantitative four diagnosis and syndrome differentiation methods and GeneChip Mouse Exon 1.0 ST Array, we observed adrenal gland gene expressions in normal Wistar rats, qi deficiency Wistar rats, SHRs with qi deficiency and qi excess, GK rats with qi deficiency and qi excess. Differentially expressed genes of steroid- and catecholamine-synthesizing enzymes and their regulatory factors were analyzed. RESULTS Thirty-one genes were differentially expressed among all syndromes. Hsd3b6 was down-regulated significantly 6.0-fold in GK rats with qi deficiency syndrome and qi excess syndrome, and Cyp11b2 was up-regulated 1.5 times in GK rats with qi deficiency syndrome. Por, Hsd11b2, and Nr2f6 were up-regulated in all syndromes, and Cyp2c23, Cyp4a3, Cyp4a8 and Cyp2e1 were down-regulated. However, Srd5a1 and Nr4a1 were up-regulated only in GK rats, and Lss was down-regulated only in SHRs. Th was up-regulated 1.5 times in SHRs with qi deficiency syndrome, GK rats with qi deficiency syndrome and GK rats with qi excess syndrome. Ddc was up-regulated 1.5 times in GK rats with qi excess syndrome. Dbh was up-regulated 3.0 times in GK rats with qi deficiency syndrome and qi excess syndrome. However, Comt was down-regulated 1.5 times in GK rats with qi deficiency syndrome and qi excess syndrome, and Mao was up-regulated 1.5 times in SHRs with qi deficiency syndrome and qi excess syndrome. CONCLUSION Some genes associated with steroid- and catecholamine-synthesizing pathways were differentially expressed in SHRs and GK rats, and the differentially expressed genes may be related to the development of traditional Chinese medicine syndromes.
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Affiliation(s)
- Zhi-qiang Pan
- School of Basic Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
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Abstract
Several signals, such as hormones and signaling molecules, have been identified as important regulators of Leydig cell differentiation and function. Conveying these signals and translating them into a genomic response to ensure an accurate physiological output requires the action of a network of transcription factors, including those belonging to the nuclear receptor superfamily. Nuclear receptors regulate expression of genes important for growth, differentiation, development, and homeostasis. Several nuclear receptors, such as steroid hormone receptors (NR3A and NR3C families), are activated upon ligand binding, whereas others, including members of the NR2C, NR2F, and NR4A families, either do not require a ligand or ligands have yet to be identified. Several nuclear receptors (e.g., NR2F2 and NR5A1) have been shown to play essential roles in Leydig cells, whereas for others (e.g., NR2B1 and NR4A1), the assessment of their function has been precluded by the early embryonic lethality associated with null mice or by redundancy mechanisms by other family members. This is now being overcome with the generation of novel approaches, including Leydig cell-specific knockout models. This review provides an overview of the nuclear receptor family of transcription factors as they relate to Leydig cell gene expression and function.
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Affiliation(s)
- Luc J Martin
- Reproduction, Perinatal, and Child Health, Research Centre du Centre Universitaire de Québec, Québec City, Québec, Canada.
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Abstract
IMPORTANCE OF THE FIELD DAX-1 (NR0B1) is an unusual orphan nuclear receptor whose function is essential for the development of the human adrenal cortex and onset of puberty. Recent data have implicated this transcription factor also in embryonic stem cell and cancer biology. AREAS COVERED IN THIS REVIEW The role of DAX-1 in the regulation of development and function of the adrenal cortex, reproductive axis, embryonic stem cells and a few types of cancer. WHAT THE READER WILL GAIN Here we review the past and present milestones in DAX-1 research and try to provide hints about the development and fields of application of DAX-1-targeted drugs in the future. TAKE HOME MESSAGE The unusual structure and restricted expression pattern of DAX-1 may offer unique opportunities for drug discovery.
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Affiliation(s)
- Enzo Lalli
- Institut de Pharmacologie Moléculaire et Cellulaire CNRS UMR 6097, Valbonne, France.
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Nedumaran B, Kim GS, Hong S, Yoon YS, Kim YH, Lee CH, Lee YC, Koo SH, Choi HS. Orphan nuclear receptor DAX-1 acts as a novel corepressor of liver X receptor alpha and inhibits hepatic lipogenesis. J Biol Chem 2010; 285:9221-32. [PMID: 20080977 DOI: 10.1074/jbc.m109.073650] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
DAX-1 (dosage-sensitive sex reversal adrenal hypoplasia congenital critical region on X chromosome, gene 1) is a member of the nuclear receptor superfamily that can repress diverse nuclear receptors and has a key role in adreno-gonadal development. Our previous report has demonstrated that DAX-1 can inhibit hepatocyte nuclear factor 4alpha transactivity and negatively regulate gluconeogenic gene expression (Nedumaran, B., Hong, S., Xie, Y. B., Kim, Y. H., Seo, W. Y., Lee, M. W., Lee, C. H., Koo, S. H., and Choi, H. S. (2009) J. Biol. Chem. 284, 27511-27523). Here, we further expand the role of DAX-1 in hepatic energy metabolism. Transfection assays have demonstrated that DAX-1 can inhibit the transcriptional activity of nuclear receptor liver X receptor alpha (LXRalpha). Physical interaction between DAX-1 and LXRalpha was confirmed Immunofluorescent staining in mouse liver shows that LXRalpha and DAX-1 are colocalized in the nucleus. Domain mapping analysis shows that the entire region of DAX-1 is involved in the interaction with the ligand binding domain region of LXRalpha. Competition analyses demonstrate that DAX-1 competes with the coactivator SRC-1 for repressing LXRalpha transactivity. Chromatin immunoprecipitation assay showed that endogenous DAX-1 recruitment on the SREBP-1c gene promoter was decreased in the presence of LXRalpha agonist. Overexpression of DAX-1 inhibits T7-induced LXRalpha target gene expression, whereas knockdown of endogenous DAX-1 significantly increases T7-induced LXRalpha target gene expression in HepG2 cells. Finally, overexpression of DAX-1 in mouse liver decreases T7-induced LXRalpha target gene expression, liver triglyceride level, and lipid accumulation. Overall, this study suggests that DAX-1, a novel corepressor of LXRalpha, functions as a negative regulator of lipogenic enzyme gene expression in liver.
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Affiliation(s)
- Balachandar Nedumaran
- Hormone Research Center, School of Biological Science and Technology, Chonnam National University, Gwangju 500-757, Korea
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Kinsey M, Smith R, Iyer AK, McCabe ERB, Lessnick SL. EWS/FLI and its downstream target NR0B1 interact directly to modulate transcription and oncogenesis in Ewing's sarcoma. Cancer Res 2009; 69:9047-55. [PMID: 19920188 DOI: 10.1158/0008-5472.can-09-1540] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Most Ewing's sarcomas harbor chromosomal translocations that encode fusions between EWS and ETS family members. The most common fusion, EWS/FLI, consists of an EWSR1-derived strong transcriptional activation domain fused, in-frame, to the DNA-binding domain-containing portion of FLI1. EWS/FLI functions as an aberrant transcription factor to regulate genes that mediate the oncogenic phenotype of Ewing's sarcoma. One of these regulated genes, NR0B1, encodes a corepressor protein, and likely plays a transcriptional role in tumorigenesis. However, the genes that NR0B1 regulates and the transcription factors it interacts with in Ewing's sarcoma are largely unknown. We used transcriptional profiling and chromatin immunoprecipitation to identify genes that are regulated by NR0B1, and compared these data to similar data for EWS/FLI. Although the transcriptional profile overlapped as expected, we also found that the genome-wide localization of NR0B1 and EWS/FLI overlapped as well, suggesting that they regulate some genes coordinately. Further analysis revealed that NR0B1 and EWS/FLI physically interact. This protein-protein interaction is likely to be relevant for the development of Ewing's sarcoma because mutations in NR0B1 that disrupt the interaction have transcriptional consequences and also abrogate oncogenic transformation. Taken together, these data suggest that EWS/FLI and NR0B1 physically interact, coordinately modulate gene expression, and mediate the transformed phenotype of Ewing's sarcoma.
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Affiliation(s)
- Michelle Kinsey
- Department of Oncological Sciences, University of Utah School of Medicine, Salt Lake City, Utah, USA
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Trevisan M, Matkovic U, Cusinato R, Toppo S, Palù G, Barzon L. Human cytomegalovirus productively infects adrenocortical cells and induces an early cortisol response. J Cell Physiol 2009; 221:629-41. [DOI: 10.1002/jcp.21896] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Nedumaran B, Hong S, Xie YB, Kim YH, Seo WY, Lee MW, Lee CH, Koo SH, Choi HS. DAX-1 acts as a novel corepressor of orphan nuclear receptor HNF4alpha and negatively regulates gluconeogenic enzyme gene expression. J Biol Chem 2009; 284:27511-23. [PMID: 19651776 DOI: 10.1074/jbc.m109.034660] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
DAX-1 (dosage-sensitive sex reversal adrenal hypoplasia congenital critical region on X chromosome, gene 1) is an atypical member of the nuclear receptor family and acts as a corepressor of a number of nuclear receptors. HNF4alpha (hepatocyte nuclear factor 4alpha) is a liver-enriched transcription factor that controls the expression of a variety of genes involved in cholesterol, fatty acid, and glucose metabolism. Here we show that DAX-1 inhibits transcriptional activity of HNF4alpha and modulates hepatic gluconeogenic gene expression. Hepatic DAX-1 expression is increased by insulin and SIK1 (salt-inducible kinase 1), whereas it is decreased in high fat diet-fed and diabetic mice. Coimmunoprecipitation assay from mouse liver samples depicts that endogenous DAX-1 interacts with HNF4alpha in vivo. In vivo chromatin immunoprecipitation assay affirms that the recruitment of DAX-1 on the phosphoenolpyruvate carboxykinase (PEPCK) gene promoter is inversely correlated with the recruitment of PGC-1alpha and HNF4alpha under fasting and refeeding, showing that DAX-1 could compete with the coactivator PGC-1alpha for binding to HNF4alpha. Adenovirus-mediated expression of DAX-1 decreased both HNF4alpha- and forskolin-mediated gluconeogenic gene expressions. In addition, knockdown of DAX-1 partially reverses the insulin-mediated inhibition of gluconeogenic gene expression in primary hepatocytes. Finally, DAX-1 inhibits PEPCK and glucose-6-phosphatase gene expression and significantly lowers fasting blood glucose level in high fat diet-fed mice, suggesting that DAX-1 can modulate hepatic gluconeogenesis in vivo. Overall, this study demonstrates that DAX-1 acts as a corepressor of HNF4alpha to negatively regulate hepatic gluconeogenic gene expression in liver.
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Affiliation(s)
- Balachandar Nedumaran
- Hormone Research Center, School of Biological Science and Technology, Chonnam National University, Gwangju 500-757, South Korea
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Mantovani RM, Pezzuti IL, Dias VMA, Silva IN. Identification of a novel mutation in DAX1/NR0B1A gene in two siblings with severe clinical presentation of adrenal hypoplasia congenita. ACTA ACUST UNITED AC 2009; 53:771-6. [DOI: 10.1590/s0004-27302009000600013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2008] [Accepted: 07/11/2009] [Indexed: 11/21/2022]
Abstract
OBJECTIVE: To search for mutations in DAX1/NR0B1A gene in siblings to establish the molecular etiology of the adrenal hypoplasia congenita (AHC), a rare potentially life-threatening disorder. CASE REPORT: We describe two siblings who presented with salt-wasting syndrome in the newborn period and received hormonal replacement for primary adrenal insufficiency. A diagnostic hypothesis of AHC was suspected because the children maintained, during hormonal treatment, low plasma 17-OH progesterone (17-OHP) and androgens, despite high ACTH levels. RESULTS: DAX1 gene was studied by molecular analysis, which showed a mutation, confirming the diagnosis in the siblings and a heterozygous state in the mother. Direct sequencing of DAX1 revealed an insertion of an adenine base (c1382-1383 A ins), which lead to a pMet461Asp substitution. CONCLUSION: A novel frameshift mutation of DAX1 gene, which established the molecular etiology of the AHC in the siblings, was identified. Obtaining a precise genetic diagnosis of this adrenal disorder, which, sometimes, cannot be confirmed only by clinical aspects, may have important implications for the long-term management of the disease.
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Sablin EP, Woods A, Krylova IN, Hwang P, Ingraham HA, Fletterick RJ. The structure of corepressor Dax-1 bound to its target nuclear receptor LRH-1. Proc Natl Acad Sci U S A 2008; 105:18390-5. [PMID: 19015525 PMCID: PMC2587556 DOI: 10.1073/pnas.0808936105] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2008] [Indexed: 11/18/2022] Open
Abstract
The Dax-1 protein is an enigmatic nuclear receptor that lacks an expected DNA binding domain, yet functions as a potent corepressor of nuclear receptors. Here we report the structure of Dax-1 bound to one of its targets, liver receptor homolog 1 (LRH-1). Unexpectedly, Dax-1 binds to LRH-1 using a new module, a repressor helix built from a family conserved sequence motif, PCFXXLP. Mutations in this repressor helix that are linked with human endocrine disorders dissociate the complex and attenuate Dax-1 function. The structure of the Dax-1:LRH-1 complex provides the molecular mechanism for the function of Dax-1 as a potent transcriptional repressor.
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Affiliation(s)
| | - April Woods
- Departments of Biochemistry and Biophysics and
| | - Irina N. Krylova
- Molecular and Cellular Pharmacology, University of California, San Francisco, CA 94143
| | - Peter Hwang
- Departments of Biochemistry and Biophysics and
| | - Holly A. Ingraham
- Molecular and Cellular Pharmacology, University of California, San Francisco, CA 94143
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Dawson MI, Xia Z, Jiang T, Ye M, Fontana JA, Farhana L, Patel B, Xue LP, Bhuiyan M, Pellicciari R, Macchiarulo A, Nuti R, Zhang XK, Han YH, Tautz L, Hobbs PD, Jong L, Waleh N, Chao WR, Feng GS, Pang Y, Su Y. Adamantyl-substituted retinoid-derived molecules that interact with the orphan nuclear receptor small heterodimer partner: effects of replacing the 1-adamantyl or hydroxyl group on inhibition of cancer cell growth, induction of cancer cell apoptosis, and inhibition of SRC homology 2 domain-containing protein tyrosine phosphatase-2 activity. J Med Chem 2008; 51:5650-62. [PMID: 18759424 DOI: 10.1021/jm800456k] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
(E)-4-[3-(1-Adamantyl)-4'-hydroxyphenyl]-3-chlorocinnamic acid (3-Cl-AHPC) induces the cell-cycle arrest and apoptosis of leukemia and cancer cells. Studies demonstrated that 3-Cl-AHPC bound to the atypical orphan nuclear receptor small heterodimer partner (SHP). Although missing a DNA-binding domain, SHP heterodimerizes with the ligand-binding domains of other nuclear receptors to repress their abilities to induce or inhibit gene expression. 3-Cl-AHPC analogues having the 1-adamantyl and phenolic hydroxyl pharmacophoric elements replaced with isosteric groups were designed, synthesized, and evaluated for their inhibition of proliferation and induction of human cancer cell apoptosis. Structure-anticancer activity relationship studies indicated the importance of both groups to apoptotic activity. Docking of 3-Cl-AHPC and its analogues to an SHP computational model that was based on the crystal structure of ultraspiracle complexed with 1-stearoyl-2-palmitoylglycero-3-phosphoethanolamine suggested why these 3-Cl-AHPC groups could influence SHP activity. Inhibitory activity against Src homology 2 domain-containing protein tyrosine phosphatase 2 (Shp-2) was also assessed. The most active Shp-2 inhibitor was found to be the 3'-(3,3-dimethylbutynyl) analogue of 3-Cl-AHPC.
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Affiliation(s)
- Marcia I Dawson
- Cancer Center and Inflammatory and Infectious Disease Center, Burnham Institute for Medical Research, La Jolla, California 92037, USA.
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Chanda D, Park JH, Choi HS. Molecular basis of endocrine regulation by orphan nuclear receptor Small Heterodimer Partner. Endocr J 2008; 55:253-68. [PMID: 17984569 DOI: 10.1507/endocrj.k07e-103] [Citation(s) in RCA: 91] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Nuclear receptors (NRs) are a unique superfamily of transcription factors (TFs) which are involved in and play a crucial role in almost all aspects of mammalian physiology. Small Heterodimer Partner (SHP; NR0B2), an exceptional member of this superfamily of NRs, have been identified as a key regulatory factor of the transcription of a variety of genes involved in diverse metabolic pathways, and are thereby an important factor in a variety of physiological functions. Since its discovery a decade ago, considerable progress has been made in the elucidation of the underlying mechanism by which SHP regulates various metabolic processes, and the results of previous studies support its importance in the maintenance of metabolic homeostasis. In this review, we have evaluated the current state of understanding of the molecular mechanisms and the resultant physiological interpretations governed by SHP.
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Affiliation(s)
- Dipanjan Chanda
- Hormone Research Center, School of Biological Sciences and Technology, Chonnam National University, Gwangju, Republic of Korea
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Barzon L, Masi G, Pacenti M, Trevisan M, Fallo F, Remo A, Martignoni G, Montanaro D, Pezzi V, Palù G. Expression of aromatase and estrogen receptors in human adrenocortical tumors. Virchows Arch 2007; 452:181-91. [PMID: 18157729 DOI: 10.1007/s00428-007-0542-0] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2007] [Revised: 10/08/2007] [Accepted: 10/30/2007] [Indexed: 11/28/2022]
Abstract
We recently demonstrated that adrenocortical carcinoma cells express aromatase and estrogen receptors (ERs) and that 17beta-estradiol enhances adrenocortical cell proliferation. To provide a clue to the role of estrogens in adrenal tumorigenesis, we investigated the expression profile of genes involved in sex steroid hormone production and activity in a large series of normal and neoplastic human adrenocortical tissues. Quantitative reverse transcriptase-polymerase chain reaction, Western blotting, and immunohistochemistry showed that ERalpha and ERbeta, androgen receptor (AR), and aromatase were expressed in the adrenal cortex and in adrenocortical tumors. ERbeta was the predominant ER subtype and was mainly expressed in the zona glomerulosa and fasciculata. Western blot analysis revealed the presence of a truncated form of AR in adrenocortical tissues. With respect to the normal adrenal cortex and adrenocortical adenomas, carcinomas were characterized by significantly lower ERbeta levels, ERalpha upregulation, and aromatase overexpression. ER expression correlated with expression of nuclear hormone receptors, suggesting they could be involved in ER modulation. In agreement with our in vitro findings, the results of this study suggest that estrogens, locally produced by aromatase, could enhance adrenocortical cell proliferation though autocrine/paracrine mechanisms. This study opens new perspectives on the potential use of antiestrogens and aromatase inhibitors as therapeutic agents against ACC.
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Affiliation(s)
- Luisa Barzon
- Department of Histology, Microbiology and Medical Biotechnologies, University of Padova, Via A. Gabelli 63, 35121, Padova, Italy.
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Iyer AK, Zhang YH, McCabe ER. LXXLL motifs and AF-2 domain mediate SHP (NR0B2) homodimerization and DAX1 (NR0B1)-DAX1A heterodimerization. Mol Genet Metab 2007; 92:151-9. [PMID: 17686645 PMCID: PMC2065763 DOI: 10.1016/j.ymgme.2007.06.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2007] [Accepted: 06/20/2007] [Indexed: 11/30/2022]
Abstract
Small heterodimer partner (SHP; NR0B2) is an unusual orphan member of the nuclear receptor superfamily that functions as a corepressor of other nuclear receptors through heterodimeric interactions. Mutations in SHP are associated with mild obesity and insulin resistance. The protein domain structure of SHP is similar to Dosage-sensitive sex reversal adrenal hypoplasia congenita (AHC) critical region on the X chromosome, gene 1 (DAX1; NR0B1). Mutations in DAX1 cause AHC with associated hypogonadotropic hypogonadism. DAX1A is an alternatively spliced isoform of DAX1 that lacks the last 80 amino acids of the DAX1 C-terminal repressor domain and is replaced by a novel 10-amino acid motif. We have previously shown homodimerization of SHP and DAX1 individually, heterodimerization of DAX1 with SHP, and heterodimerization of DAX1 with DAX1A. In these studies, we investigated the domains and residues of SHP involved in SHP homodimerization and DAX1-SHP heterodimerization and also further characterized DAX1-DAX1 homodimerization and DAX1-DAX1A heterodimerization. We showed involvement of the SHP LXXLL motifs and AF-2 domain in SHP homodimerization and DAX1-SHP heterodimerization. We demonstrated redundancy of the LXXLL motifs in DAX1 homodimerization. While DAX1A subcellular localization is mostly cytoplasmic, DAX1-DAX1A heterodimers existed in the nucleus, suggesting differential functions for DAX1A in each compartment. We showed that the AF-2 domain of DAX1 is involved in DAX1-DAX1A heterodimerization. These results indicate that NR0B family members use similar mechanisms for homodimerization as well as heterodimerization. These resemble coactivator-receptor interactions that may have potential functional consequences for molecular mechanisms of the NR0B family.
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Affiliation(s)
- Anita K. Iyer
- Department of Human Genetics, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
- Corresponding author: E.R.B. McCabe, M.D., Ph.D., Department of Pediatrics, 22-412 MDCC, David Geffen School of Medicine at UCLA, 10833 Le Conte Avenue, Los Angeles, CA, 90095-1752, USA. Phone 310-825-5095, Fax 310-206-4584, Email
| | - Yao-Hua Zhang
- Department of Pediatrics, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Edward R.B. McCabe
- Department of Human Genetics, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
- Department of Pediatrics, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
- Mattel Children's Hospital at UCLA
- UCLA Molecular Biology Institute, Los Angeles, CA, USA
- Department of Bioengineering, Henry Samueli School of Engineering and Applied Science, UCLA, Los Angeles, CA, USA
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Abstract
DAX1 (NR0B1) is a nuclear receptor with a characteristic C-terminal ligand binding domain, but an atypical DNA binding domain. Mutations in the DAX1 gene cause adrenal hypoplasia congenita (AHC) establishing its biological importance. Recent studies highlight the complexities of DAX1 regulation and function. There is considerable phenotypic variability in AHC suggesting the existence of DAX1 modifier genes and environmental influences on DAX1 function. The findings of an alternatively spliced DAX1A, more common than DAX1 in all tissues except testis, of DAX1 homodimers, and of DAX1 heterodimers with a number of transcription factor partners including DAX1A and SHP point to an expanded transcription regulatory network under DAX1 control. Model organisms (mice and zebrafish) are being used to identify other DAX1 functions and modifier genes to understand the pathogenesis of AHC and the lack of genotype-phenotype correlation.
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Affiliation(s)
- Edward R B McCabe
- Mattel Children's Hospital at UCLA, Los Angeles, CA 90095-1752, United States.
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Lee YS, Chanda D, Sim J, Park YY, Choi HS. Structure and function of the atypical orphan nuclear receptor small heterodimer partner. INTERNATIONAL REVIEW OF CYTOLOGY 2007; 261:117-58. [PMID: 17560281 DOI: 10.1016/s0074-7696(07)61003-1] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The small heterodimer partner (SHP; NROB2) is a member of the nuclear receptor superfamily and is classified as an "orphan" subgroup, as its ligand has not yet been identified. SHP lacks the classical DNA-binding domain found in most nuclear receptors and functions as a transcriptional coregulator by directly interacting with nuclear receptors and other transcription factors. SHP regulates the transcription of a variety of target genes and controls a variety of physiological functions. For the past 10 years, great progress has been made in our understanding of the mechanism of action of SHP and the regulation of SHP gene expression. Many of the results imply that SHP has a variety of roles in the regulation of metabolic homeostasis. In this review, we discuss the current state of understanding of the structure, expression, and function of the orphan nuclear receptor, SHP.
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Affiliation(s)
- Yong-Soo Lee
- Hormone Research Center, School of Biological Sciences and Technology, Chonnam National University, Gwangju 500-757, Korea
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