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Neggazi S, Hamlat N, Canaple L, Gauthier K, Samarut J, Bricca G, Aouichat-Bouguerra S, Beylot M. TRα inhibits arterial renin-angiotensin system expression and prevents cholesterol accumulation in vascular smooth muscle cells. Ann Endocrinol (Paris) 2018; 80:89-95. [PMID: 30292450 DOI: 10.1016/j.ando.2018.09.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 07/07/2018] [Accepted: 09/04/2018] [Indexed: 12/14/2022]
Abstract
OBJECTIVES The tissue renin-angiotensin system (tRAS) plays a key role in the maintenance of cellular homeostasis but is also implicated in atherosclerosis. Thyroid hormone (TH) contributes, via genomic effects, to control of tRAS gene expression in the arterial wall and vascular smooth muscle cells (VSMCs). We investigated the specific functions of TH receptors-α and -β (TRα and TRβ) on tRAS gene expression in the aorta and VSMCs, and the potential protective effect of TRα against atherosclerosis. MATERIAL AND METHODS Using aorta and cultured aortic VSMCs from TRα and TRβ deficient mice, tRAS gene expression was analyzed by determining mRNA levels on real-time PCR. Gene regulation under cholesterol loading mimicking atherosclerosis conditions was also examined in VSMCs in vitro. RESULTS TRα deletion significantly increased expression of angiotensinogen (AGT) and angiotensin II receptor type 1 subtype a (AT1Ra) at transcriptional level in aorta, a tissue with high TRα expression level. TRα activity thus seems to be required for maintenance of physiological levels of AGTand AT1Raexpression in the arterial wall. In addition, during cholesterol loading, TRα deletion significantly increased cholesterol content in VSMCs, with a weaker decrease in AGTexpression. CONCLUSION TRα seems to have an inhibitory impact on AGTand AT1Raexpression, and loss of TRα function in TRα0/0 mice increases tRAS expression in the aortic wall. More importantly, TRα deletion significantly increases VSMC cholesterol content. Our results are consistent with a protective role of TRα against atherosclerosis.
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Affiliation(s)
- Samia Neggazi
- University of Sciences and Technology Houari Boumediene (USTHB), Faculty of Biological Sciences, Laboratory of Biology and Physiology of Organisms (Cellular and Molecular Physiopathology team), BP 32 El Alia, 16111 Bab Ezzouar, Algeria.
| | - Nadjiba Hamlat
- University of Sciences and Technology Houari Boumediene (USTHB), Faculty of Biological Sciences, Laboratory of Biology and Physiology of Organisms (Cellular and Molecular Physiopathology team), BP 32 El Alia, 16111 Bab Ezzouar, Algeria.
| | - Laurence Canaple
- CNRS, Inra, University of Lyon, Functional Genomics Institute of Lyon, École normale supérieure de Lyon, 46, avenue d'Italie, 69364 Lyon, France.
| | - Karine Gauthier
- CNRS, Inra, University of Lyon, Functional Genomics Institute of Lyon, École normale supérieure de Lyon, 46, avenue d'Italie, 69364 Lyon, France.
| | - Jacques Samarut
- CNRS, Inra, University of Lyon, Functional Genomics Institute of Lyon, École normale supérieure de Lyon, 46, avenue d'Italie, 69364 Lyon, France.
| | - Giampiero Bricca
- EA 4173, Functional Genomics of Arterial Hypertension, University Claude Bernard Lyon 1, 69008 Lyon, France
| | - Souhila Aouichat-Bouguerra
- University of Sciences and Technology Houari Boumediene (USTHB), Faculty of Biological Sciences, Laboratory of Biology and Physiology of Organisms (Cellular and Molecular Physiopathology team), BP 32 El Alia, 16111 Bab Ezzouar, Algeria.
| | - Michel Beylot
- Platform ANIPHY, University Claude Bernard Lyon 1, 69008 Lyon, France.
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Neggazi S, Canaple L, Hamlat N, Gauthier K, Samarut J, Bricca G, Aouichat-Bouguerra S, Beylot M. Thyroid Hormone Receptor Alpha Deletion in ApoE-/- Mice Alters the Arterial Renin-Angiotensin System and Vascular Smooth Muscular Cell Cholesterol Metabolism. J Vasc Res 2018; 55:224-234. [PMID: 30092589 DOI: 10.1159/000491430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Accepted: 06/21/2018] [Indexed: 11/19/2022] Open
Abstract
Thyroid hormone (TH) regulates gene transcription by binding to TH receptors (TRs). TRs regulate the genes of lipid metabolism and the renin-angiotensin system (RAS). We examined the effect of TRα deletion in ApoE-/- mice (DKO mice) on the following: (i) the expression of genes controlling cholesterol metabolism and tissue (t)RAS in the liver and aorta and (ii) the expression of these genes and the regulation of cholesterol content in cultured vascular smooth muscle cells (VSMCs). TRα deletion in ApoE-/- mice led to the repression of genes involved in the synthesis and influx of cholesterol in the liver. However, TRα deletion in the arterial wall suppressed the expression of genes involved in the esterification and excretion of cholesterol and enhanced the expression of angiotensinogen (AGT). The VSMCs of the ApoE-/- and DKO mice increased their cholesterol content during cholesterol loading, but failed to increase the expression of ATP-binding cassette transporter A1 (ABCA1). T3 addition partially corrected these abnormalities in the cells of the ApoE-/- mice but not those of the DKO mice. In conclusion, TRα deletion in ApoE-/- mice slightly increases the expression of tRAS in the aorta and aggravates the dysregulation of cholesterol content in the VSMCs.
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Affiliation(s)
- Samia Neggazi
- USTHB, Faculty of Biological Sciences, Laboratory of Biology and Physiology of Organisms (Cellular and Molecular Physiopathology team), BP 32 El Alia, Algiers, Algeria
| | - Laurence Canaple
- Functional Genomics Institute of Lyon, University of Lyon, CNRS, INRA, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Nadjiba Hamlat
- USTHB, Faculty of Biological Sciences, Laboratory of Biology and Physiology of Organisms (Cellular and Molecular Physiopathology team), BP 32 El Alia, Algiers, Algeria
| | - Karine Gauthier
- Functional Genomics Institute of Lyon, University of Lyon, CNRS, INRA, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Jacques Samarut
- Functional Genomics Institute of Lyon, University of Lyon, CNRS, INRA, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Giampiero Bricca
- Functional Genomics of Arterial Hypertension, EA 4173, University Lyon 1, Lyon, France
| | - Souhila Aouichat-Bouguerra
- USTHB, Faculty of Biological Sciences, Laboratory of Biology and Physiology of Organisms (Cellular and Molecular Physiopathology team), BP 32 El Alia, Algiers, Algeria
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Uchuya-Castillo J, Aznar N, Frau C, Martinez P, Le Nevé C, Marisa L, Penalva LOF, Laurent-Puig P, Puisieux A, Scoazec JY, Samarut J, Ansieau S, Plateroti M. Increased expression of the thyroid hormone nuclear receptor TRα1 characterizes intestinal tumors with high Wnt activity. Oncotarget 2018; 9:30979-30996. [PMID: 30123421 PMCID: PMC6089551 DOI: 10.18632/oncotarget.25741] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2018] [Accepted: 06/12/2018] [Indexed: 01/10/2023] Open
Abstract
Our previous work demonstrated a key function of the thyroid hormone nuclear receptor TRα1, a T3-modulated transcription factor, in controlling intestinal development and homeostasis via the Wnt and Notch pathways. Importantly, increased expression of TRα1 in the intestinal epithelium in a mutated Apc genetic background (vil-TRα1/Apc+/1638N mice) accelerated tumorigenesis and contributed to a more aggressive tumor phenotype compared to that of the Apc mutants alone. Therefore, the aim of this study was to determine the relevance of this synergistic effect in human colorectal cancers and to gain insights into the mechanisms involved. We analyzed cohorts of patients by in silico and experimental approaches and observed increased TRα1 expression and a significant correlation between TRα1 levels and Wnt activity. TRα1 loss-of-function and gain-of-function in Caco2 cell lines not only confirmed that TRα1 levels control Wnt activity but also demonstrated the role of TRα1 in regulating cell proliferation and migration. Finally, upon investigation of the molecular mechanisms responsible for the Wnt-TRα1 association, we described the repression by TRα1 of several Wnt inhibitors, including Frzb, Sox17 and Wif1. In conclusion, our results underline an important functional interplay between the thyroid hormone nuclear receptor TRα1 and the canonical Wnt pathway in intestinal cancer initiation and progression. More importantly, we show for the first time that the expression of TRα1 is induced in human colorectal cancers.
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Affiliation(s)
- Joel Uchuya-Castillo
- Centre de Recherche en Cancérologie de Lyon, INSERM U1052, CNRS UMR5286, Université de Lyon, Université Lyon 1, Centre Léon Bérard, Département de la recherche, Lyon 69000, France
| | - Nicolas Aznar
- Centre de Recherche en Cancérologie de Lyon, INSERM U1052, CNRS UMR5286, Université de Lyon, Université Lyon 1, Centre Léon Bérard, Département de la recherche, Lyon 69000, France
| | - Carla Frau
- Centre de Recherche en Cancérologie de Lyon, INSERM U1052, CNRS UMR5286, Université de Lyon, Université Lyon 1, Centre Léon Bérard, Département de la recherche, Lyon 69000, France
| | - Pierre Martinez
- Centre de Recherche en Cancérologie de Lyon, INSERM U1052, CNRS UMR5286, Université de Lyon, Université Lyon 1, Centre Léon Bérard, Département de la recherche, Lyon 69000, France
| | - Clementine Le Nevé
- Centre de Recherche en Cancérologie de Lyon, INSERM U1052, CNRS UMR5286, Université de Lyon, Université Lyon 1, Centre Léon Bérard, Département de la recherche, Lyon 69000, France
| | - Laetitia Marisa
- Programme Cartes d'Identité des Tumeurs (CIT), Ligue Nationale Contre le Cancer, Paris 75000, France
| | - Luiz O F Penalva
- Children's Cancer Research Institute, University of Texas Health Science Center at San Antonio, TX 78229, USA
| | | | - Alain Puisieux
- Centre de Recherche en Cancérologie de Lyon, INSERM U1052, CNRS UMR5286, Université de Lyon, Université Lyon 1, Centre Léon Bérard, Département de la recherche, Lyon 69000, France
| | | | - Jacques Samarut
- Institute de Génomique Fonctionnelle de Lyon, ENS de Lyon, Lyon 69342, France
| | - Stephane Ansieau
- Centre de Recherche en Cancérologie de Lyon, INSERM U1052, CNRS UMR5286, Université de Lyon, Université Lyon 1, Centre Léon Bérard, Département de la recherche, Lyon 69000, France
| | - Michelina Plateroti
- Centre de Recherche en Cancérologie de Lyon, INSERM U1052, CNRS UMR5286, Université de Lyon, Université Lyon 1, Centre Léon Bérard, Département de la recherche, Lyon 69000, France
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4
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Flamant F, Cheng SY, Hollenberg AN, Moeller LC, Samarut J, Wondisford FE, Yen PM, Refetoff S. Thyroid Hormone Signaling Pathways: Time for a More Precise Nomenclature. Endocrinology 2017; 158:2052-2057. [PMID: 28472304 PMCID: PMC6283428 DOI: 10.1210/en.2017-00250] [Citation(s) in RCA: 108] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Accepted: 04/24/2017] [Indexed: 12/31/2022]
Abstract
Current literature makes a distinction between two pathways for thyroid hormone signaling: genomic and nongenomic. However, this classification is a source of confusion. We propose a clarification in the nomenclature that may help to avoid unproductive controversies and favor progress in this field of research. Four types of thyroid hormone signaling are defined, and the experimental criteria for classification are discussed.
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Affiliation(s)
- Frédéric Flamant
- Institut de Génomique Fonctionnelle de Lyon, INRA USC 1370, Université de Lyon, Université Lyon 1, CNRS UMR 5242, Ecole Normale Supérieure de Lyon, 69364 Lyon cedex 07, France
| | - Sheue-Yann Cheng
- Gene Regulation Section, Laboratory of Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892-6264
| | - Anthony N Hollenberg
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts 02215
| | - Lars C Moeller
- Division of Laboratory Research, Department of Endocrinology and Metabolic Diseases, University of Duisburg-Essen, 45127 Essen, Germany
| | - Jacques Samarut
- Institut de Génomique Fonctionnelle de Lyon, INRA USC 1370, Université de Lyon, Université Lyon 1, CNRS UMR 5242, Ecole Normale Supérieure de Lyon, 69364 Lyon cedex 07, France
| | - Fredric E Wondisford
- Department of Medicine, Rutgers-Robert Wood Johnson Medical School, New Brunswick, New Jersey 08903
| | - Paul M Yen
- Laboratory of Hormonal Regulation, Cardiovascular and Metabolic Disorders Program, Duke-NUS Medical School, 169857, Singapore
| | - Samuel Refetoff
- Department of Medicine, University of Chicago, Chicago, Illinois 60637
- Department of Pediatrics, University of Chicago, Chicago, Illinois 60637
- Department of Genetics, University of Chicago, Chicago, Illinois 60637
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5
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Hameed S, Patterson M, Dhillo WS, Rahman SA, Ma Y, Holton C, Gogakos A, Yeo GS, Lam BY, Polex-Wolf J, Fenske W, Bell J, Anastasovska J, Samarut J, Bloom SR, Bassett JD, Williams GR, Gardiner JV. Thyroid Hormone Receptor Beta in the Ventromedial Hypothalamus Is Essential for the Physiological Regulation of Food Intake and Body Weight. Cell Rep 2017; 19:2202-2209. [PMID: 28614708 PMCID: PMC5478879 DOI: 10.1016/j.celrep.2017.05.066] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Revised: 04/06/2017] [Accepted: 05/19/2017] [Indexed: 02/02/2023] Open
Abstract
The obesity epidemic is a significant global health issue. Improved understanding of the mechanisms that regulate appetite and body weight will provide the rationale for the design of anti-obesity therapies. Thyroid hormones play a key role in metabolic homeostasis through their interaction with thyroid hormone receptors (TRs), which function as ligand-inducible transcription factors. The TR-beta isoform (TRβ) is expressed in the ventromedial hypothalamus (VMH), a brain area important for control of energy homeostasis. Here, we report that selective knockdown of TRβ in the VMH of adult mice results in severe obesity due to hyperphagia and reduced energy expenditure. The observed increase in body weight is of a similar magnitude to murine models of the most extreme forms of monogenic obesity. These data identify TRβ in the VMH as a major physiological regulator of food intake and energy homeostasis.
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Affiliation(s)
- Saira Hameed
- Section of Investigative Medicine, Division of Diabetes, Endocrinology and Metabolism, Imperial College London, London W12 0NN, UK
| | - Michael Patterson
- Section of Investigative Medicine, Division of Diabetes, Endocrinology and Metabolism, Imperial College London, London W12 0NN, UK,Department of Life Sciences, University of Roehampton, London SW15 4JD, UK
| | - Waljit S. Dhillo
- Section of Investigative Medicine, Division of Diabetes, Endocrinology and Metabolism, Imperial College London, London W12 0NN, UK
| | - Sofia A. Rahman
- Molecular Endocrinology Laboratory, Hammersmith Campus, Imperial College London, London W12 0NN, UK
| | - Yue Ma
- Section of Investigative Medicine, Division of Diabetes, Endocrinology and Metabolism, Imperial College London, London W12 0NN, UK
| | - Christopher Holton
- Section of Investigative Medicine, Division of Diabetes, Endocrinology and Metabolism, Imperial College London, London W12 0NN, UK
| | - Apostolos Gogakos
- Molecular Endocrinology Laboratory, Hammersmith Campus, Imperial College London, London W12 0NN, UK
| | - Giles S.H. Yeo
- University of Cambridge Metabolic Research Laboratories, Wellcome Trust-MRC Institute of Metabolic Science, Addenbrooke’s Hospital, Cambridge CB2 0QQ, UK
| | - Brian Y.H. Lam
- University of Cambridge Metabolic Research Laboratories, Wellcome Trust-MRC Institute of Metabolic Science, Addenbrooke’s Hospital, Cambridge CB2 0QQ, UK
| | - Joseph Polex-Wolf
- University of Cambridge Metabolic Research Laboratories, Wellcome Trust-MRC Institute of Metabolic Science, Addenbrooke’s Hospital, Cambridge CB2 0QQ, UK
| | - Wiebke Fenske
- Section of Investigative Medicine, Division of Diabetes, Endocrinology and Metabolism, Imperial College London, London W12 0NN, UK
| | - Jimmy Bell
- Metabolic and Molecular Imaging Group, Imperial College London, London W12 0NN, UK
| | - Jelena Anastasovska
- Metabolic and Molecular Imaging Group, Imperial College London, London W12 0NN, UK
| | - Jacques Samarut
- Institut de Génomique Fonctionnelle de Lyon, Ecole Normale Supérieure de Lyon, 69364 Lyon, France
| | - Stephen R. Bloom
- Section of Investigative Medicine, Division of Diabetes, Endocrinology and Metabolism, Imperial College London, London W12 0NN, UK
| | - J.H. Duncan Bassett
- Molecular Endocrinology Laboratory, Hammersmith Campus, Imperial College London, London W12 0NN, UK
| | - Graham R. Williams
- Molecular Endocrinology Laboratory, Hammersmith Campus, Imperial College London, London W12 0NN, UK,Corresponding author
| | - James V. Gardiner
- Section of Investigative Medicine, Division of Diabetes, Endocrinology and Metabolism, Imperial College London, London W12 0NN, UK,Corresponding author
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6
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Chen R, Zhang Q, Duan X, York P, Chen GD, Yin P, Zhu H, Xu M, Chen P, Wu Q, Li D, Samarut J, Xu G, Zhang P, Cao X, Li J, Wong J. The 5-Hydroxymethylcytosine (5hmC) Reader UHRF2 Is Required for Normal Levels of 5hmC in Mouse Adult Brain and Spatial Learning and Memory. J Biol Chem 2017; 292:4533-4543. [PMID: 28115522 DOI: 10.1074/jbc.m116.754580] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2016] [Revised: 12/27/2016] [Indexed: 12/21/2022] Open
Abstract
UHRF2 has been implicated as a novel regulator for both DNA methylation (5mC) and hydroxymethylation (5hmC), but its physiological function and role in DNA methylation/hydroxymethylation are unknown. Here we show that in mice, UHRF2 is more abundantly expressed in the brain and a few other tissues. Uhrf2 knock-out mice are viable and fertile and exhibit no gross defect. Although there is no significant change of DNA methylation, the Uhrf2 null mice exhibit a reduction of 5hmC in the brain, including the cortex and hippocampus. Furthermore, the Uhrf2 null mice exhibit a partial impairment in spatial memory acquisition and retention. Consistent with the phenotype, gene expression profiling uncovers a role for UHRF2 in regulating neuron-related gene expression. Finally, we provide evidence that UHRF2 binds 5hmC in cells but does not appear to affect the TET1 enzymatic activity. Together, our study supports UHRF2 as a bona fide 5hmC reader and further demonstrates a role for 5hmC in neuronal function.
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Affiliation(s)
- Ruoyu Chen
- From the Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Qiao Zhang
- From the Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Xiaoya Duan
- From the Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Philippe York
- the Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, Texas 77030
| | - Guo-Dong Chen
- the Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, Shanghai 200031, China
| | - Pengcheng Yin
- the Key Laboratory of Brain Functional Genomics, Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, East China Normal University, Shanghai 200062, China
| | - Haijun Zhu
- From the Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Meichen Xu
- the Key Laboratory of Brain Functional Genomics, Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, East China Normal University, Shanghai 200062, China
| | - Peilin Chen
- From the Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Qihan Wu
- From the Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Dali Li
- From the Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Jacques Samarut
- the Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS UMR5242, Ecole Normale Supérieure de Lyon, Lyon 69007, France, and
| | - Guoliang Xu
- the Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, Shanghai 200031, China
| | - Pumin Zhang
- the Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, Texas 77030
| | - Xiaohua Cao
- the Key Laboratory of Brain Functional Genomics, Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, East China Normal University, Shanghai 200062, China
| | - Jiwen Li
- From the Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai 200241, China,
| | - Jiemin Wong
- From the Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai 200241, China, .,the Collaborative Innovation Center for Cancer Medicine, Sun Yat-Sen University Cancer Center, Guangzhou 510060, China
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Tribollet V, Barenton B, Kroiss A, Vincent S, Zhang L, Forcet C, Cerutti C, Périan S, Allioli N, Samarut J, Vanacker JM. miR-135a Inhibits the Invasion of Cancer Cells via Suppression of ERRα. PLoS One 2016; 11:e0156445. [PMID: 27227989 PMCID: PMC4881992 DOI: 10.1371/journal.pone.0156445] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 05/13/2016] [Indexed: 01/04/2023] Open
Abstract
MicroRNA-135a (miR-135a) down-modulates parameters of cancer progression and its expression is decreased in metastatic breast cancers (as compared to non-metastatic tumors) as well as in prostate tumors relative to normal tissue. These expression and activity patterns are opposite to those of the Estrogen-Related Receptor α (ERRα), an orphan member of the nuclear receptor family. Indeed high expression of ERRα correlates with poor prognosis in breast and prostate cancers, and the receptor promotes various traits of cancer aggressiveness including cell invasion. Here we show that miR-135a down-regulates the expression of ERRα through specific sequences of its 3'UTR. As a consequence miR-135a also reduces the expression of downstream targets of ERRα. miR-135a also decreases cell invasive potential in an ERRα-dependent manner. Our results suggest that the decreased expression of miR-135a in metastatic tumors leads to elevated ERRα expression, resulting in increased cell invasion capacities.
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Affiliation(s)
- Violaine Tribollet
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS UMR5242, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Bruno Barenton
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS UMR5242, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Auriane Kroiss
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS UMR5242, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Séverine Vincent
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS UMR5242, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Ling Zhang
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS UMR5242, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Christelle Forcet
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS UMR5242, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Catherine Cerutti
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS UMR5242, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Séverine Périan
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS UMR5242, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Nathalie Allioli
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS UMR5242, Ecole Normale Supérieure de Lyon, Lyon, France
- Institut des Sciences Pharmaceutiques et Biologiques, Faculté de Pharmacie, Université de Lyon, Lyon, France
| | - Jacques Samarut
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS UMR5242, Ecole Normale Supérieure de Lyon, Lyon, France
- Faculté de Médecine Lyon-Sud, Université de Lyon, Lyon, France
- UMOMT, Centre Hospitalier Lyon-Sud, Hospices Civils de Lyon, Lyon, France
| | - Jean-Marc Vanacker
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS UMR5242, Ecole Normale Supérieure de Lyon, Lyon, France
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8
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Han R, Ye L, Jiang X, Zhou X, Billon C, Guan W, Gauthier K, Fang W, Wang W, Samarut J, Ning G. Characteristics of patients with late manifestation of resistance thyroid hormone syndrome: a single-center experience. Endocrine 2015; 50:689-97. [PMID: 26041374 DOI: 10.1007/s12020-015-0622-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Accepted: 04/27/2015] [Indexed: 11/30/2022]
Abstract
Resistance to thyroid hormone (RTH) is a rare genetic disease caused by reduced tissue sensitivity to thyroid hormone. The hallmark of RTH is elevated serum levels of thyroid hormone with unsuppressed thyrotropin (TSH). However, the most common form of RTH results from minor defects in the ligand-binding domain or hinge domain of the TRβ gene, resulting in impaired T3-induced transcriptional activity, often showing mild presentation. Early diagnosis can be challenging. The objective of the current study was to characterize this specific group of RTH patients. This was a retrospective study. Patients diagnosed as RTH with TRβ mutations were enrolled in a single institute between 2004 and 2014. A total of 14 patients were diagnosed as RTH with mutation in THβ gene. The median age at diagnosis was 22.5 (IQR: 13.25-32.75). Goiter was the most common clinical finding. TSH was significantly elevated after TRH injection (median peak was 21.83 μIU/l, IQR: 13.59-31.48), 9.2-fold compared to the basal level. We found 10 mutations in TRβ gene, all located in the last four exons, and including one novel mutation, H271D. In vitro study found that H271D mutation reduced TR affinity to T3. Four patients with intact thyroid were diagnosed after 16 years old, defined as late manifestation. Compared to those diagnosed before 10 years old, patients with late manifestation presented with normal growth and mental development. Interestingly, three of them carried R438H mutation. We identified a novel p.H271D mutation in TRβ associated with RTH. Endocrinologists should be alert that RTH is frequently found in euthyroid patients with mild symptoms and often leads to misleading diagnosis as well as inappropriate treatment.
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Affiliation(s)
- Rulai Han
- Shanghai Clinical Center for Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Department of Endocrine and Metabolic Diseases, Rui-Jin Hospital, Shanghai Jiao-Tong University School of Medicine, Shanghai, 200025, People's Republic of China
| | - Lei Ye
- Shanghai Clinical Center for Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Department of Endocrine and Metabolic Diseases, Rui-Jin Hospital, Shanghai Jiao-Tong University School of Medicine, Shanghai, 200025, People's Republic of China.
- Shanghai Key Laboratory for Endocrine Tumors and Shanghai Clinical Center for Endocrine and Metabolic Diseases, Ruijin Hospital, 197 Ruijin 2nd Road, Shanghai, 200025, People's Republic of China.
| | - Xiaohua Jiang
- Shanghai Clinical Center for Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Department of Endocrine and Metabolic Diseases, Rui-Jin Hospital, Shanghai Jiao-Tong University School of Medicine, Shanghai, 200025, People's Republic of China
| | - Xiaoyi Zhou
- Shanghai Clinical Center for Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Department of Endocrine and Metabolic Diseases, Rui-Jin Hospital, Shanghai Jiao-Tong University School of Medicine, Shanghai, 200025, People's Republic of China
| | - Cyrielle Billon
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS, INRA, Ecole Normale Supérieure de Lyon, 46 allée d'Italie, 69364, Lyon Cedex 07, France
| | - Wenyue Guan
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS, INRA, Ecole Normale Supérieure de Lyon, 46 allée d'Italie, 69364, Lyon Cedex 07, France
| | - Karine Gauthier
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS, INRA, Ecole Normale Supérieure de Lyon, 46 allée d'Italie, 69364, Lyon Cedex 07, France
| | - Weiyuan Fang
- Shanghai Clinical Center for Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Department of Endocrine and Metabolic Diseases, Rui-Jin Hospital, Shanghai Jiao-Tong University School of Medicine, Shanghai, 200025, People's Republic of China
| | - Weiqing Wang
- Shanghai Clinical Center for Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Department of Endocrine and Metabolic Diseases, Rui-Jin Hospital, Shanghai Jiao-Tong University School of Medicine, Shanghai, 200025, People's Republic of China
| | - Jacques Samarut
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS, INRA, Ecole Normale Supérieure de Lyon, 46 allée d'Italie, 69364, Lyon Cedex 07, France
| | - Guang Ning
- Shanghai Clinical Center for Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Department of Endocrine and Metabolic Diseases, Rui-Jin Hospital, Shanghai Jiao-Tong University School of Medicine, Shanghai, 200025, People's Republic of China
- Laboratory for Endocrine & Metabolic Diseases of Institute of Health Science, Shanghai Jiaotong University School of Medicine and Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 227 South Chong Qing Road, Shanghai, 200025, People's Republic of China
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9
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Kroiss A, Vincent S, Decaussin-Petrucci M, Meugnier E, Viallet J, Ruffion A, Chalmel F, Samarut J, Allioli N. Androgen-regulated microRNA-135a decreases prostate cancer cell migration and invasion through downregulating ROCK1 and ROCK2. Oncogene 2014; 34:2846-55. [PMID: 25065599 DOI: 10.1038/onc.2014.222] [Citation(s) in RCA: 93] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Revised: 06/12/2014] [Accepted: 06/15/2014] [Indexed: 12/20/2022]
Abstract
Androgen signaling, via the androgen receptor (AR), is crucial in mediating prostate cancer (PCa) initiation and progression. Identifying new downstream effectors of the androgens/AR pathway will allow a better understanding of these mechanisms and could reveal novel biomarkers and/or therapeutic agents to improve the rate of patient survival. We compared the microRNA expression profiles in androgen-sensitive LNCaP cells stimulated or not with 1 nM R1881 by performing a high-throughput reverse transcriptase-quantitative PCR and found that miR-135a was upregulated. After androgen stimulation, we showed that AR directly activates the transcription of miR-135a2 gene by binding to an androgen response element in the promoter region. Our findings identify miR-135a as a novel effector in androgens/AR signaling. Using xenograft experiments in chick embryos and adult male mice, we showed that miR-135a overexpression decreases in vivo invasion abilities of prostate PC-3 cells. Through in vitro wound-healing migration and invasion assays, we demonstrated that this effect is mediated through downregulating ROCK1 and ROCK2 expression, two genes that we characterized as miR-135a direct target genes. In human surgical samples from prostatectomy, we observed that miR-135a expression was lower in tumoral compared with paired adjacent normal tissues, mainly in tumors classified with a high Gleason score (⩾8). Moreover, miR-135a expression is lower in invasive tumors, showing extraprostatic extension, as compared with intraprostatic localized tumors. In tumor relative to normal glands, we also showed a more frequently higher ROCK1 protein expression determined using a semi-quantitative immunohistochemistry analysis. Therefore, in tumor cells, the lower miR-135a expression could lead to a higher ROCK1 protein expression, which could explain their invasion abilities. The highlighted relationship between miR-135a expression level and the degree of disease aggressiveness suggests that miR-135a may be considered as a prognostic marker in human PCa.
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Affiliation(s)
- A Kroiss
- Université de Lyon, Ecole Normale Supérieure de Lyon, Université Claude Bernard Lyon 1, Institut de Génomique Fonctionnelle de Lyon (IGFL), Lyon, France
| | - S Vincent
- Université de Lyon, Ecole Normale Supérieure de Lyon, Université Claude Bernard Lyon 1, Institut de Génomique Fonctionnelle de Lyon (IGFL), Lyon, France
| | - M Decaussin-Petrucci
- 1] Université de Lyon, Ecole Normale Supérieure de Lyon, Université Claude Bernard Lyon 1, Institut de Génomique Fonctionnelle de Lyon (IGFL), Lyon, France [2] Faculté de Médecine et de Maïeutique Lyon-Sud-Charles Mérieux, Université Claude Bernard Lyon 1, Pierre-Bénite, France [3] Service d'Anatomie et de Cytologie Pathologiques, Centre Hospitalier Lyon-Sud, Hospices Civils de Lyon, Pierre-Bénite, France
| | - E Meugnier
- Laboratoire CarMen, INSERM U1060, INRA1362, Université Claude Bernard Lyon 1, Faculté de Médecine et de Maïeutique Lyon-Sud-Charles Mérieux, Oullins, France
| | - J Viallet
- In Ovo, Institut Albert Bonniot, CRI INSERM/UJF U823, Université de Grenoble, La Tronche Cedex, France
| | - A Ruffion
- 1] Université de Lyon, Ecole Normale Supérieure de Lyon, Université Claude Bernard Lyon 1, Institut de Génomique Fonctionnelle de Lyon (IGFL), Lyon, France [2] Faculté de Médecine et de Maïeutique Lyon-Sud-Charles Mérieux, Université Claude Bernard Lyon 1, Pierre-Bénite, France [3] Service d'Urologie, Centre Hospitalier Lyon-Sud, Hospices Civils de Lyon, Pierre-Bénite, France
| | - F Chalmel
- GERHM, INSERM U1085-Irset, Université Rennes 1, Rennes, France
| | - J Samarut
- 1] Université de Lyon, Ecole Normale Supérieure de Lyon, Université Claude Bernard Lyon 1, Institut de Génomique Fonctionnelle de Lyon (IGFL), Lyon, France [2] Faculté de Médecine et de Maïeutique Lyon-Sud-Charles Mérieux, Université Claude Bernard Lyon 1, Pierre-Bénite, France [3] Service de Biochimie Biologie Moleculaire Sud, Centre Hospitalier Lyon-Sud, Hospices Civils de Lyon, Pierre-Bénite, France
| | - N Allioli
- 1] Université de Lyon, Ecole Normale Supérieure de Lyon, Université Claude Bernard Lyon 1, Institut de Génomique Fonctionnelle de Lyon (IGFL), Lyon, France [2] Institut des Sciences Pharmaceutiques et Biologiques (ISPB)-Faculté de Pharmacie de Lyon, Université Claude Bernard Lyon 1, Lyon, France
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10
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Billon C, Canaple L, Fleury S, Deloire A, Beylot M, Dombrowicz D, Del Carmine P, Samarut J, Gauthier K. TRα protects against atherosclerosis in male mice: identification of a novel anti-inflammatory property for TRα in mice. Endocrinology 2014; 155:2735-45. [PMID: 24797634 DOI: 10.1210/en.2014-1098] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Hypothyroidism is associated with an increased occurrence of atherosclerosis, suggesting some protective role for thyroid hormones (THs). Hypercholesterolemia is one of the major risk factor to develop this disease. Here, we show that the well-known TH cholesterol lowering effect was dependent on TH nuclear receptor (TR)β liver activity. But most importantly, TRα was also shown to contribute of slowing down atherosclerosis progression via an independent mechanism. Introduction of TRα(0/0) deletion in the ApoE(-/-) background accelerated the appearance of plaques. Earlier cholesterol accumulation was detected in aorta macrophages, likely due to impaired cholesterol efflux. The IL-1β inflammatory cytokine was elevated in serum and macrophages in correlation with an activation of the AKT/nuclear factor κB pathway in these cells. Inhibition of AKT prevented inflammation and restored normal cholesterol efflux. Similar low-grade inflammation was identified in TRα(0/0) male mice. Thus, the mere absence of TRα is associated with elevated levels of cytokines likely responsible for cholesterol accumulation and atherosclerosis. This TRα protective activity should be relevant for other inflammatory pathologies.
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Affiliation(s)
- Cyrielle Billon
- Institut de Génomique Fonctionnelle de Lyon (C.B., L.C., A.D., J.S., K.G.), Université de Lyon, Université Lyon 1, Centre National de la Recherche Scientifique. Institut National de la Recherche Agronomique, Ecole Normale Supérieure de Lyon, 69364 Lyon, France; Inserm Unité 1011 (S.F., D.D.), University of Lille Nord de France and Institut Pasteur de Lille, 59000 Lille, France; and Inserm Equipe Région-Inserm 22/Equipe Associée 4173 (M.B.) and Anira-ANIPHY (P.d.C.), Faculté Rockefeller, Université Lyon 1, 69008 Lyon, France
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11
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Prost M, Canaple L, Samarut J, Hasserodt J. Tagging Live Cells that Express Specific Peptidase Activity with Solid-State Fluorescence. Chembiochem 2014; 15:1413-7. [DOI: 10.1002/cbic.201402091] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Indexed: 11/11/2022]
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12
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Ipuy M, Billon C, Micouin G, Samarut J, Andraud C, Bretonnière Y. Fluorescent push-pull pH-responsive probes for ratiometric detection of intracellular pH. Org Biomol Chem 2014; 12:3641-8. [PMID: 24756609 DOI: 10.1039/c4ob00147h] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A family of fluorescent push-pull pH-responsive probes based on 2-dicyanomethylidene-3-cyano-4,5,5-trimethyl-2,5-dihydrofuran as a strong electron acceptor group is described. Small structural variations allow obtaining pK(a) ranging from 4.8 to 8.6, underlining the role of the substituent in modulating the acidic properties. Remarkable changes in the optical properties (in particular the fluorescence intensity ratios) were observed as a function of pH. The most interesting probes with pK(a) close to neutrality were used for ratiometric imaging of intracellular pH.
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Affiliation(s)
- Martin Ipuy
- Laboratoire de Chimie de l'ENS de Lyon, CNRS UMR 5182, Ecole Normale Supérieure de Lyon, Université Lyon I, 46 allée d'Italie, 69364 Lyon cedex 07, France.
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13
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Blanc S, Ruggiero F, Birot AM, Acloque H, Décimo D, Lerat E, Ohlmann T, Samarut J, Mey A. Subcellular localization of ENS-1/ERNI in chick embryonic stem cells. PLoS One 2014; 9:e92039. [PMID: 24643087 PMCID: PMC3958431 DOI: 10.1371/journal.pone.0092039] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2013] [Accepted: 02/19/2014] [Indexed: 11/18/2022] Open
Abstract
The protein of retroviral origin ENS-1/ERNI plays a major role during neural plate development in chick embryos by controlling the activity of the epigenetic regulator HP1γ, but its function in the earlier developmental stages is still unknown. ENS-1/ERNI promoter activity is down-regulated upon differentiation but the resulting protein expression has never been examined. In this study, we present the results obtained with custom-made antibodies to gain further insights into ENS-1 protein expression in Chicken embryonic stem cells (CES) and during their differentiation. First, we show that ENS-1 controls the activity of HP1γ in CES and we examined the context of its interaction with HP1γ. By combining immunofluorescence and western blot analysis we show that ENS-1 is localized in the cytoplasm and in the nucleus, in agreement with its role on gene's promoter activity. During differentiation, ENS-1 decreases in the cytoplasm but not in the nucleus. More precisely, three distinct forms of the ENS-1 protein co-exist in the nucleus and are differently regulated during differentiation, revealing a new level of control of the protein ENS-1. In silico analysis of the Ens-1 gene copies and the sequence of their corresponding proteins indicate that this pattern is compatible with at least three potential regulation mechanisms, each accounting only partially. The results obtained with the anti-ENS-1 antibodies presented here reveal that the regulation of ENS-1 expression in CES is more complex than expected, providing new tracks to explore the integration of ENS-1 in CES cells regulatory networks.
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Affiliation(s)
- Sophie Blanc
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS UMR 5242, INRA USC 1370, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Florence Ruggiero
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS UMR 5242, INRA USC 1370, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Anne-Marie Birot
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS UMR 5242, INRA USC 1370, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Hervé Acloque
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS UMR 5242, INRA USC 1370, Ecole Normale Supérieure de Lyon, Lyon, France
- Laboratoire de Génétique Cellulaire-INRA, ENVT, Castanet Tolosan, France
| | - Didier Décimo
- CIRI, International Center for Infectiology Research, Université de Lyon, INSERM U1111, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Emmanuelle Lerat
- Université de Lyon, Lyon, France; Université Lyon 1, Villeurbanne, France; CNRS, UMR5558, Laboratoire de Biométrie et Biologie Evolutive, Villeurbanne, France
| | - Théophile Ohlmann
- CIRI, International Center for Infectiology Research, Université de Lyon, INSERM U1111, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Jacques Samarut
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS UMR 5242, INRA USC 1370, Ecole Normale Supérieure de Lyon, Lyon, France
- * E-mail: (JS); (AM)
| | - Anne Mey
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS UMR 5242, INRA USC 1370, Ecole Normale Supérieure de Lyon, Lyon, France
- * E-mail: (JS); (AM)
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14
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Refetoff S, Bassett JD, Beck-Peccoz P, Bernal J, Brent G, Chatterjee K, De Groot LJ, Dumitrescu AM, Jameson JL, Kopp PA, Murata Y, Persani L, Samarut J, Weiss RE, Williams GR, Yen PM. Classification and proposed nomenclature for inherited defects of thyroid hormone action, cell transport, and metabolism. Thyroid 2014; 24:407-9. [PMID: 24588711 PMCID: PMC3950730 DOI: 10.1089/thy.2013.3393.nomen] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Samuel Refetoff
- Department of Medicine, The University of Chicago, Chicago, Illinois
- Department of Pediatrics, The University of Chicago, Chicago, Illinois
- Department of Genetics, The University of Chicago, Chicago, Illinois
| | | | - Paolo Beck-Peccoz
- Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
- Fondazione Ca’ Granda Policlinico, Milan, Italy
| | - Juan Bernal
- Institute for Biomedical Research, Higher Council for Scientific Research, Autonomous University of Madrid, Madrid, Spain
- Center for Biomedical Network Research on Rare Diseases (CIBERER), Madrid, Spain
| | - Gregory Brent
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, California
| | - Krishna Chatterjee
- Wellcome-Medical Research Council Institute of Metabolic Science, University of Cambridge, Cambridge, United Kingdom
| | | | | | - J. Larry Jameson
- Raymond and Ruth Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Peter A. Kopp
- Division of Endocrinology, Metabolism, and Molecular Medicine and Center for Genetic Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Yoshiharu Murata
- Research Institute of Environmental Medicine, Nagoya University, Nagoya, Japan
| | - Luca Persani
- Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
- Italian Institute for Auxology, Milan, Italy
| | | | - Roy E. Weiss
- Department of Medicine, The University of Chicago, Chicago, Illinois
- Department of Pediatrics, The University of Chicago, Chicago, Illinois
| | | | - Paul M. Yen
- Laboratory of Hormone Action, Singapore Institute of Clinical Sciences, Singapore
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15
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Refetoff S, Bassett JHD, Beck-Peccoz P, Bernal J, Brent G, Chatterjee K, De Groot LJ, Dumitrescu AM, Jameson JL, Kopp PA, Murata Y, Persani L, Samarut J, Weiss RE, Williams GR, Yen PM. Classification and proposed nomenclature for inherited defects of thyroid hormone action, cell transport, and metabolism. J Clin Endocrinol Metab 2014; 99:768-70. [PMID: 24823702 PMCID: PMC3942236 DOI: 10.1210/jc.2013-3393] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
- Samuel Refetoff
- Departments of Medicine (S.R., A.M.D., R.E.W.), Pediatrics (S.R., R.E.W.), and Genetics (S.R.), The University of Chicago, Chicago, Illinois 60637; Department of Medicine (J.H.D.B., G.R.W.), Imperial College London, Hammersmith Campus, London W12 0NN, United Kingdom; Department of Clinical Sciences and Community Health (P.B.-P., L.P.), University of Milan, Fondazione Ca' Granda Policlinico (P.B.-P.), and Istituto Auxologico Italiano (L.P.), 20133 Milan, Italy; Instituto de Investigaciones Biomédicas (J.B.), Consejo Superior de Investigaciones Científicas-Universidad Autonoma de Madrid and Centro de Investigación Biomédica en Red de Enfermedades Raras, 28029 Madrid, Spain; Department of Medicine (G.B.), David Geffen School of Medicine, University of California at Los Angeles, California 90095; Wellcome-Medical Research Council Institute of Metabolic Science (K.C.), University of Cambridge, Cambridge CB2 0QQ, United Kingdom; Thyroidmanager and Endotext (L.J.D.G.), South Dartmouth, Massachusetts 02748; Raymond and Ruth Perelman School of Medicine (J.L.J.), University of Pennsylvania, Philadelphia, Pennsylvania 19104; Division of Endocrinology, Metabolism, and Molecular Medicine and Center for Genetic Medicine (P.A.K.), Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611; Research Institute of Environmental Medicine (Y.M.), Nagoya University, Nagoya 466-8550, Japan; Ecole Normale Supérieure de Lyon (J.S.), 69342 Lyon, France; and Laboratory of Hormone Action, Singapore Institute of Clinical Sciences (P.M.Y.), Singapore 138669
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16
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Refetoff S, Bassett JD, Beck-Peccoz P, Bernal J, Brent G, Chatterjee K, De Groot LJ, Dumitrescu AM, Jameson JL, Kopp PA, Murata Y, Persani L, Samarut J, Weiss RE, Williams GR, Yen PM. Classification and proposed nomenclature for inherited defects of thyroid hormone action, cell transport, and metabolism. Eur Thyroid J 2014; 3:7-9. [PMID: 24847459 PMCID: PMC4005262 DOI: 10.1159/000358180] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Accepted: 11/22/2013] [Indexed: 11/19/2022] Open
Affiliation(s)
- Samuel Refetoff
- Department of Medicine, The University of Chicago, Chicago, Ill., USA
- Department of Pediatrics, The University of Chicago, Chicago, Ill., USA
- Department of Genetics, The University of Chicago, Chicago, Ill., USA
| | | | - Paolo Beck-Peccoz
- Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
- Fondazione Ca' Granda Policlinico, Milan, Italy
| | - Juan Bernal
- Instituto de Investigaciones Biomédicas, Consejo Superior de Investigaciones Científicas-Universidad Autonoma de Madrid and Centro de Investigación Biomédica en Red de Enfermedades Raras, Madrid, Spain
| | - Gregory Brent
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, Calif., USA
| | - Krishna Chatterjee
- Wellcome-Medical Research Council Institute of Metabolic Science, University of Cambridge, Cambridge, UK
| | | | | | - J. Larry Jameson
- Raymond and Ruth Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pa
| | - Peter A. Kopp
- Division of Endocrinology, Metabolism, and Molecular Medicine and Center for Genetic Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Ill., USA
| | - Yoshiharu Murata
- Research Institute of Environmental Medicine, Nagoya University, Nagoya, Japan
| | - Luca Persani
- Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
- Istituto Auxologico Italiano, Milan, Italy
| | | | - Roy E. Weiss
- Department of Medicine, The University of Chicago, Chicago, Ill., USA
- Department of Pediatrics, The University of Chicago, Chicago, Ill., USA
| | | | - Paul M. Yen
- Laboratory of Hormone Action, Singapore Institute of Clinical Sciences, Singapore, Singapore
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17
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Selmi-Ruby S, Bouazza L, Obregon MJ, Conscience A, Flamant F, Samarut J, Borson-Chazot F, Rousset B. The targeted inactivation of TRβ gene in thyroid follicular cells suggests a new mechanism of regulation of thyroid hormone production. Endocrinology 2014; 155:635-46. [PMID: 24265449 DOI: 10.1210/en.2013-1435] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Thyroid epithelial cells, or thyrocytes, express functional thyroid hormone receptors but no precise role has yet been assigned to either TRα or TRβ in the thyroid gland. In this study, we analyzed the impact of inactivating the TRβ gene in the thyroid of mice. First, we generated a mouse line named Thyr-Cre, expressing the Cre recombinase under the control of the thyroglobulin gene promoter, which led to a complete recombination of floxed genes in thyrocytes. Thyr-Cre mice were then crossed with TRβ floxed mice (TRβ(flox/flox)) to obtain a thyrocyte-selective deletion of TRβ. Thyr-TRβ(-/-) mice were characterized by a decrease in the size and functional activity of the thyroid gland. These alterations were associated with a decrease in plasma TSH concentration. Surprisingly, Thyr-TRβ(-/-) displayed elevated serum T(4) and rT(3) concentrations with no significant change in serum T(3) levels. Their intrathyroidal free T(4) and rT(3) contents were also elevated, whereas the ratio of serum T(4) to thyroid free T(4) was decreased by comparison with wild-type littermates. Also, within the thyroid, deiodinases D1 and D2 were reduced as well as the expression levels of genes encoding monocarboxylate transporters (Mct8 and Mct10). Such a decrease in intrathyroidal deiodination of T(4) and in the expression of genes encoding thyroid hormone transporters may contribute to the primary overproduction of T(4) observed in Thyr-TRβ(-/-) mice. In conclusion, these data show that the control of thyroid hormone production involves not only TRβ-dependent mechanisms acting at the level of hypothalamus and pituitary but also TRβ-dependent mechanisms acting at the thyroid level.
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Affiliation(s)
- Samia Selmi-Ruby
- Inserm Unité 1052 (S.S.-R., F.B.-C., B.R.), Lyon, France; Centre National de la Recherche Scientifique Unité Mixte de Recherche 5286 (S.S.-R., F.B.-C., B.R.), Lyon, France; Université Claude Bernard Lyon 1 (S.S.-R., L.B., F.B.-C., B.R.), Faculté de Médecine Lyon-Est-Site Laennec, Lyon Cedex 08, F-69372 France; Instituto de Investigaciones Biomedicas (Consejo Superior de Investigaciones Científicas-Universidad Autonoma Madrid) (M.-J.O.), Madrid, M-28029 Spain; and Institut de Génomique Fonctionnelle de Lyon (A.C., F.F., J.S.), Lyon, F-69007 France
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18
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Altintas DM, Allioli N, Decaussin M, de Bernard S, Ruffion A, Samarut J, Vlaeminck-Guillem V. Differentially expressed androgen-regulated genes in androgen-sensitive tissues reveal potential biomarkers of early prostate cancer. PLoS One 2013; 8:e66278. [PMID: 23840433 PMCID: PMC3696068 DOI: 10.1371/journal.pone.0066278] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2013] [Accepted: 05/03/2013] [Indexed: 11/24/2022] Open
Abstract
Background Several data favor androgen receptor implication in prostate cancer initiation through the induction of several gene activation programs. The aim of the study is to identify potential biomarkers for early diagnosis of prostate cancer (PCa) among androgen-regulated genes (ARG) and to evaluate comparative expression of these genes in normal prostate and normal prostate-related androgen-sensitive tissues that do not (or rarely) give rise to cancer. Methods ARG were selected in non-neoplastic adult human prostatic epithelial RWPE-1 cells stably expressing an exogenous human androgen receptor, using RNA-microarrays and validation by qRT-PCR. Expression of 48 preselected genes was quantified in tissue samples (seminal vesicles, prostate transitional zones and prostate cancers, benign prostatic hypertrophy obtained from surgical specimens) using TaqMan® low-density arrays. The diagnostic performances of these potential biomarkers were compared to that of genes known to be associated with PCa (i.e. PCA3 and DLX1). Results and Discussion By crossing expression studies in 26 matched PCa and normal prostate transitional zone samples, and 35 matched seminal vesicle and PCa samples, 14 genes were identified. Similarly, 9 genes were overexpressed in 15 benign prostatic hypertrophy samples, as compared to PCa samples. Overall, we selected 8 genes of interest to evaluate their diagnostic performances in comparison with that of PCA3 and DLX1. Among them, 3 genes: CRYAB, KCNMA1 and SDPR, were overexpressed in all 3 reference non-cancerous tissues. The areas under ROC curves of these genes reached those of PCA3 (0.91) and DLX1 (0.94). Conclusions We identified ARG with reduced expression in PCa and with significant diagnostic values for discriminating between cancerous and non-cancerous prostatic tissues, similar that of PCA3. Given their expression pattern, they could be considered as potentially protective against prostate cancer. Moreover, they could be complementary to known genes overexpressed in PCa and included along with them in multiplex diagnostic tools.
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Affiliation(s)
- Dogus Murat Altintas
- Institut de Génomique Fonctionnelle de Lyon (IGFL), Université de Lyon, CNRS UMR5242, INRA1288, Ecole Normale Supérieure de Lyon, Lyon, France
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Gandrillon O, Rascle A, Samarut J. The v-erba oncogene - a superb tool for dissecting the involvement of nuclear hormone receptors in differentiation and neoplasia (review). Int J Oncol 2012; 6:215-31. [PMID: 21556527 DOI: 10.3892/ijo.6.1.215] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The v-erbA oncogene has been discovered as one of the two viral oncogenes carried by the avian leukemia retrovirus AEV. It is derived from the c-erbA protooncogene which encodes the alpha form of the nuclear receptor for the thyroid hormone triiodothyronine (T3R). This receptor belongs to a large family of nuclear hormone receptors that function as ligand-regulated transcription factors and the v-erbA oncoprotein has been shown to function as an antagonist of normal T3R and related receptors in the control of transcription. It is thus the first dominant negative transcription factor acting as an oncogene described to date. Functional and biochemical dissections of this oncogene have brought many informations on the mechanisms of action of normal receptors and on the ways through which altered receptors can contribute to oncogenic transformation. The v-erbA model is widely used as a reference to investigate the involvement of nuclear hormone receptors in the development of human cancers.
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Altintas DM, Shukla MS, Goutte-Gattat D, Angelov D, Rouault JP, Dimitrov S, Samarut J. Direct cooperation between androgen receptor and E2F1 reveals a common regulation mechanism for androgen-responsive genes in prostate cells. Mol Endocrinol 2012; 26:1531-41. [PMID: 22771493 DOI: 10.1210/me.2012-1016] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
We have studied the regulation of ATAD2 gene expression by androgens in prostate cells. ATAD2 is a coactivator of the androgen receptor (AR) and the MYC protein. We showed that ATAD2 expression is directly regulated by AR via an AR binding sequence (ARBS) located in the distal enhancer of its regulatory region. The gene is also regulated by the E2F1 transcription factor. Using knockdown and chromatin immunoprecipitation technique approaches, we could demonstrate that AR and E2F1 functionally collaborate and physically interact between each other. From the analysis of chromatin conformation, we conclude that this cooperation results from a chromatin looping over the ATAD2 promoter region between the ARBS and E2F1 binding site in an androgen-dependent manner. Furthermore, we could show that several genes overexpressed in prostate cancer and potentially involved in several aspects of tumor development have an ARBS and an E2F1 binding site in their regulatory regions and exhibit the same mechanism of regulation by both transcription factors as ATAD2.
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Affiliation(s)
- D M Altintas
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Claude Bernard Lyon 1, F-69346 Lyon Cedex 07, France
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22
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Mey A, Acloque H, Lerat E, Gounel S, Tribollet V, Blanc S, Curton D, Birot AM, Nieto MA, Samarut J. The endogenous retrovirus ENS-1 provides active binding sites for transcription factors in embryonic stem cells that specify extra embryonic tissue. Retrovirology 2012; 9:21. [PMID: 22420414 PMCID: PMC3362752 DOI: 10.1186/1742-4690-9-21] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2011] [Accepted: 03/15/2012] [Indexed: 01/01/2023] Open
Abstract
Background Long terminal repeats (LTR) from endogenous retroviruses (ERV) are source of binding sites for transcription factors which affect the host regulatory networks in different cell types, including pluripotent cells. The embryonic epiblast is made of pluripotent cells that are subjected to opposite transcriptional regulatory networks to give rise to distinct embryonic and extraembryonic lineages. To assess the transcriptional contribution of ERV to early developmental processes, we have characterized in vitro and in vivo the regulation of ENS-1, a host adopted and developmentally regulated ERV that is expressed in chick embryonic stem cells. Results We show that Ens-1 LTR activity is controlled by two transcriptional pathways that drive pluripotent cells to alternative developmental fates. Indeed, both Nanog that maintains pluripotency and Gata4 that induces differentiation toward extraembryonic endoderm independently activate the LTR. Ets coactivators are required to support Gata factors' activity thus preventing inappropriate activation before epigenetic silencing occurs during differentiation. Consistent with their expression patterns during chick embryonic development, Gata4, Nanog and Ets1 are recruited on the LTR in embryonic stem cells; in the epiblast the complementary expression of Nanog and Gata/Ets correlates with the Ens-1 gene expression pattern; and Ens-1 transcripts are also detected in the hypoblast, an extraembryonic tissue expressing Gata4 and Ets2, but not Nanog. Accordingly, over expression of Gata4 in embryos induces an ectopic expression of Ens-1. Conclusion Our results show that Ens-1 LTR have co-opted conditions required for the emergence of extraembryonic tissues from pluripotent epiblasts cells. By providing pluripotent cells with intact binding sites for Gata, Nanog, or both, Ens-1 LTR may promote distinct transcriptional networks in embryonic stem cells subpopulations and prime the separation between embryonic and extraembryonic fates.
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Affiliation(s)
- Anne Mey
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, CNRS, INRA, Ecole Normale Supérieure de Lyon, France.
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23
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Allioli N, Vincent S, Vlaeminck-Guillem V, Decaussin-Petrucci M, Ragage F, Ruffion A, Samarut J. TM4SF1, a novel primary androgen receptor target gene over-expressed in human prostate cancer and involved in cell migration. Prostate 2011; 71:1239-50. [PMID: 21656834 DOI: 10.1002/pros.21340] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2010] [Accepted: 12/13/2010] [Indexed: 11/09/2022]
Abstract
BACKGROUND The Androgen Receptor (AR) plays a key role in controlling prostate gland homeostasis and contributes to prostate carcinogenesis. The identification of its target genes should provide new candidates that may be implicated in cancer initiation and progression. METHODS Transcriptomic experiments and chromatin immunoprecipitation were combined to identify direct androgen regulated genes. Real-time quantitative PCR (RT-qPCR) analyses were performed to measure TM4SF1 mRNA levels in prostate cancer and benign prostatic hyperplasia (BPH) specimens. Immunohistochemical methods were used to compare TM4SF1 protein expression profiles in the same cohort. A targeted siRNAs knockdown strategy was used, prior to wound healing assays, to analyze the role of TM4SF1 in cell migration in vitro. RESULTS We demonstrate for the first time that TM4SF1 is a direct target gene of the AR, a transcription factor of the steroid nuclear receptor family. A functional androgen response element was identified in the promoter region of the gene. In addition, TM4SF1 mRNA expression was higher in cancer samples compared to BPH tissues. The TM4SF1 protein mediates cell motility of prostate cancer cells where it is predominantly localized in the cytoplasm, in contrast to its apical membrane localization in normal prostate epithelial cells. CONCLUSIONS Our results reveal a novel function for TM4SF1 in AR signaling. The TM4SF1 mRNA expression is higher in prostate cancer tissues as compared to BPH samples. Inhibition of cell migration after targeted knockdown of TM4SF1 protein expression suggests its contribution to prostate cancer cell metastasis.
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MESH Headings
- Antigens, Surface/biosynthesis
- Antigens, Surface/genetics
- Antigens, Surface/physiology
- Biomarkers, Tumor/biosynthesis
- Biomarkers, Tumor/genetics
- Biomarkers, Tumor/physiology
- Cell Line, Tumor
- Cell Migration Inhibition/genetics
- Gene Expression Regulation, Neoplastic
- HeLa Cells
- Humans
- Male
- Neoplasm Proteins/biosynthesis
- Neoplasm Proteins/genetics
- Neoplasm Proteins/physiology
- Prostatic Hyperplasia/genetics
- Prostatic Hyperplasia/metabolism
- Prostatic Neoplasms/genetics
- Prostatic Neoplasms/metabolism
- Receptors, Androgen/biosynthesis
- Receptors, Androgen/genetics
- Receptors, Androgen/physiology
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Affiliation(s)
- Nathalie Allioli
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Lyon, France.
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Touti F, Singh AK, Maurin P, Canaple L, Beuf O, Samarut J, Hasserodt J. An Electroneutral Macrocyclic Iron(II) Complex That Enhances MRI Contrast in Vivo. J Med Chem 2011; 54:4274-8. [DOI: 10.1021/jm2002298] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Fayçal Touti
- Laboratoire de Chimie, UMR 5182 CNRS, Ecole Normale Superieure de Lyon, Lyon, France
| | - Akhilesh Kumar Singh
- Laboratoire de Chimie, UMR 5182 CNRS, Ecole Normale Superieure de Lyon, Lyon, France
| | - Philippe Maurin
- Laboratoire de Chimie, UMR 5182 CNRS, Ecole Normale Superieure de Lyon, Lyon, France
| | - Laurence Canaple
- Institut de Génomique Fonctionnelle de Lyon, IGFL UMR 5242 CNRS, ENS Lyon, INRA 1288, UCBL, Lyon, France
| | - Olivier Beuf
- CREATIS, Université de Lyon, UMR 5220 CNRS, Inserm U1044, INSA-Lyon, Université Lyon 1, Lyon, France
| | - Jacques Samarut
- Institut de Génomique Fonctionnelle de Lyon, IGFL UMR 5242 CNRS, ENS Lyon, INRA 1288, UCBL, Lyon, France
| | - Jens Hasserodt
- Laboratoire de Chimie, UMR 5182 CNRS, Ecole Normale Superieure de Lyon, Lyon, France
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Altintas DM, Vlaeminck V, Angelov D, Dimitrov S, Samarut J. Cell cycle regulated expression of NCoR might control cyclic expression of androgen responsive genes in an immortalized prostate cell line. Mol Cell Endocrinol 2011; 332:149-62. [PMID: 20974212 DOI: 10.1016/j.mce.2010.10.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2010] [Revised: 09/27/2010] [Accepted: 10/11/2010] [Indexed: 01/03/2023]
Abstract
In this work we have studied the mechanisms of regulation of expression of androgen receptor (AR) target genes. We have used an immortalized non-tumorigenic prostate cell line RWPE-1-AR(tag) constitutively expressing an exogenous AR as a model. We observed that all studied AR target genes exhibited a specific expression during the G1 phase of the cell cycle despite the constitutive expression of AR. Importantly, we found that the expression of NCoR, an AR co-repressor, was downregulated during the G1 phase and expressed as mRNA and protein specifically during the S phase. The role of NCoR in repressing androgen-induced expression of AR target genes in S phase was further demonstrated by altering expression of NCoR during the cell cycle through knockdown or induced overexpression. Using two alternative techniques we show that AR binds directly to target DNA in the chromatin only during the G1 phase. These data support the hypothesis that NCoR might control a cell cycle dependent regulation of expression AR target genes in prostate cells.
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Affiliation(s)
- D M Altintas
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS, INRA, Ecole Normale Supérieure de Lyon, Lyon, France
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Caillier M, Thénot S, Tribollet V, Birot AM, Samarut J, Mey A. Role of the epigenetic regulator HP1γ in the control of embryonic stem cell properties. PLoS One 2010; 5:e15507. [PMID: 21085495 PMCID: PMC2981578 DOI: 10.1371/journal.pone.0015507] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2010] [Accepted: 10/06/2010] [Indexed: 12/30/2022] Open
Abstract
The unique properties of embryonic stem cells (ESC) rely on long-lasting self-renewal and their ability to switch in all adult cell type programs. Recent advances have shown that regulations at the chromatin level sustain both ESC properties along with transcription factors. We have focused our interest on the epigenetic modulator HP1γ (Heterochromatin Protein 1, isoform γ) that binds histones H3 methylated at lysine 9 (meH3K9) and is highly plastic in its distribution and association with the transcriptional regulation of specific genes during cell fate transitions. These characteristics of HP1γ make it a good candidate to sustain the ESC flexibility required for rapid program changes during differentiation. Using RNA interference, we describe the functional role of HP1γ in mouse ESC. The analysis of HP1γ deprived cells in proliferative and in various differentiating conditions was performed combining functional assays with molecular approaches (RT-qPCR, microarray). We show that HP1γ deprivation slows down the cell cycle of ESC and decreases their resistance to differentiating conditions, rendering the cells poised to differentiate. In addition, HP1γ depletion hampers the differentiation to the endoderm as compared with the differentiation to the neurectoderm or the mesoderm. Altogether, our results reveal the role of HP1γ in ESC self-renewal and in the balance between the pluripotent and the differentiation programs.
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Affiliation(s)
- Maïa Caillier
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS, INRA, Ecole Normale Supérieure de Lyon, France
| | - Sandrine Thénot
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS, INRA, Ecole Normale Supérieure de Lyon, France
| | - Violaine Tribollet
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS, INRA, Ecole Normale Supérieure de Lyon, France
| | - Anne-Marie Birot
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS, INRA, Ecole Normale Supérieure de Lyon, France
| | - Jacques Samarut
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS, INRA, Ecole Normale Supérieure de Lyon, France
- * E-mail: (AM); (JS)
| | - Anne Mey
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS, INRA, Ecole Normale Supérieure de Lyon, France
- * E-mail: (AM); (JS)
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Kowalik MA, Perra A, Pibiri M, Cocco MT, Samarut J, Plateroti M, Ledda-Columbano GM, Columbano A. TRbeta is the critical thyroid hormone receptor isoform in T3-induced proliferation of hepatocytes and pancreatic acinar cells. J Hepatol 2010; 53:686-92. [PMID: 20638743 DOI: 10.1016/j.jhep.2010.04.028] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/24/2009] [Revised: 03/29/2010] [Accepted: 04/19/2010] [Indexed: 12/04/2022]
Abstract
BACKGROUND & AIMS Thyroid hormones elicit many cellular and metabolic effects in various organs. Most of these actions, including mitogenesis, are mediated by the thyroid hormone 3,5,3'-triiodo-l-thyronine (T3) nuclear receptors (TRs). They are transcription factors, expressed as different isoforms encoded by the TRalpha and TRbeta genes. Here, experiments were performed to determine whether (i) T3-induces hepatocyte proliferation in mouse liver and pancreas, and, (ii) which TR isoform, is responsible for its mitogenic effect. METHODS Cell proliferation was measured by bromodeoxyuridine (BrdU) incorporation after T3 or the TRbeta agonist GC-1 in liver and pancreas of CD-1, C57BL, or TRalpha(0/0) mice. Cell cycle-associated proteins were measured by Western blot. RESULTS T3 added to the diet at a concentration of 4 mg/kg caused a striking increase in BrdU incorporation in mouse hepatocytes. Increased BrdU incorporation was associated with enhanced protein levels of cyclin D1 and PCNA and decreased levels of p27. Treatment with GC-1, a selective agonist of the TRbeta isoform, also induced a strong mitogenic response of mouse hepatocytes and pancreatic acinar cells which was similar to that elicited by T3. Finally, treatment with T3 of mice TRalpha(0/0) induced a proliferative response in the liver and pancreas, similar to that of their wild type counterpart. CONCLUSIONS These results demonstrate that T3 is a powerful inducer of cell proliferation in mouse liver and suggest that the beta-isoform is responsible for the hepatomitogenic activity of T3. The same isoform seems to also mediate the proliferation of mouse pancreatic acinar cells.
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Affiliation(s)
- Marta A Kowalik
- Department of Toxicology, Oncology and Molecular Pathology Unit, University of Cagliari, Italy
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Rezza A, Skah S, Roche C, Nadjar J, Samarut J, Plateroti M. The overexpression of the putative gut stem cell marker Musashi-1 induces tumorigenesis through Wnt and Notch activation. J Cell Sci 2010; 123:3256-65. [PMID: 20826465 DOI: 10.1242/jcs.065284] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
The RNA-binding protein Musashi-1 (Msi1) has been proposed as a marker of intestinal epithelial stem cells. These cells are responsible for the continuous renewal of the intestinal epithelium. Although the function of Msi1 has been studied in several organs from different species and in mammalian cell lines, its function and molecular regulation in mouse intestinal epithelium progenitor cells are still undefined. We describe here that, in these cells, the expression of Msi1 is regulated by the canonical Wnt pathway, through a mechanism involving a functional Tcf/Lef binding site on its promoter. An in vitro study in intestinal epithelium primary cultures showed that Msi1 overexpression promotes progenitor proliferation and activates Wnt and Notch pathways. Moreover, Msi1-overexpressing cells exhibit tumorigenic properties in xenograft experiments. These data point to a positive feedback loop between Msi1 and Wnt in intestinal epithelial progenitors. They also suggest that Msi1 has oncogenic properties in these cells, probably through induction of both the Wnt and Notch pathways.
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Affiliation(s)
- Amelie Rezza
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS, INRA, Ecole Normale Supérieure de Lyon, 46 Allée d'Italie, 69364 Lyon Cedex 07, France
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Gauthier K, Billon C, Bissler M, Beylot M, Lobaccaro JM, Vanacker JM, Samarut J. Thyroid hormone receptor beta (TRbeta) and liver X receptor (LXR) regulate carbohydrate-response element-binding protein (ChREBP) expression in a tissue-selective manner. J Biol Chem 2010; 285:28156-63. [PMID: 20615868 DOI: 10.1074/jbc.m110.146241] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Thyroid hormone (TR) and liver X (LXR) receptors are transcription factors involved in lipogenesis. Both receptors recognize the same consensus DNA-response element in vitro. It was previously shown that their signaling pathways interact in the control of cholesterol elimination in the liver. In the present study, carbohydrate-response element-binding protein (ChREBP), a major transcription factor controlling the activation of glucose-induced lipogenesis in liver, is characterized as a direct target of thyroid hormones (TH) in liver and white adipose tissue (WAT), the two main lipogenic tissues in mice. Using genetic and molecular approaches, ChREBP is shown to be specifically regulated by TRbeta but not by TRalpha in vivo, even in WAT where both TR isoforms are expressed. However, this isotype specificity is not found in vitro. This TRbeta specific regulation correlates with the loss of TH-induced lipogenesis in TRbeta(-/-) mice. Fasting/refeeding experiments show that TRbeta is not required for the activation of ChREBP expression particularly marked in WAT following refeeding. However, TH can stimulate ChREBP expression in WAT even under fasting conditions, suggesting completely independent pathways. Because ChREBP has been described as an LXR target, the interaction of LXR and TRbeta in ChREBP regulation was assayed both in vitro and in vivo. Each receptor recognizes a different response element on the ChREBP promoter, located only 8 bp apart. There is a cross-talk between LXR and TRbeta signaling on the ChREBP promoter in liver but not in WAT where LXR does not regulate ChREBP expression. The molecular basis for this cross-talk has been determined in in vitro systems.
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Affiliation(s)
- Karine Gauthier
- Institut de Génomique Fonctionnelle de Lyon, Université Lyon 1, CNRS, INRA, Ecole Normale Supérieure de Lyon, 46 allée d'Italie, 69364 Lyon, France.
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Kress E, Skah S, Sirakov M, Nadjar J, Gadot N, Scoazec JY, Samarut J, Plateroti M. Cooperation between the thyroid hormone receptor TRalpha1 and the WNT pathway in the induction of intestinal tumorigenesis. Gastroenterology 2010; 138:1863-74. [PMID: 20114049 DOI: 10.1053/j.gastro.2010.01.041] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2009] [Revised: 12/30/2009] [Accepted: 01/21/2010] [Indexed: 02/08/2023]
Abstract
BACKGROUND & AIMS Colorectal tumorigenesis is a multistep process involving the alteration of oncogenes and tumor suppressor genes, leading to the deregulation of molecular pathways that govern intestinal homeostasis. We have previously shown that the thyroid hormone receptor alpha1 (TRalpha1) controls intestinal development and homeostasis through the WNT pathway. More precisely, TRalpha1 directly enhances the transcription of several components of this pathway, allowing increased expression of beta-catenin/Tcf4 target genes and stimulation of cell proliferation. Because the WNT pathway is a major player in controlling intestinal homeostasis, we addressed whether the TRalpha1 receptor has tumor-inducing potential. METHODS We generated mice overexpressing TRalpha1 specifically in the intestinal epithelium in a wild-type (vil-TRalpha1) or a WNT-activated (vil-TRalpha1/Apc(+/1638N)) genetic background. RESULTS The intestine of vil-TRalpha1 mice presents aberrant intestinal mucosal architecture and increased cell proliferation and develops adenoma at a low rate. However, TRalpha1 overexpression is unable to induce cancer development. On the contrary, we observed accelerated tumorigenesis in vil-TRalpha1/Apc(+/1638N) mice compared with the Apc(+/1638N) mutants. CONCLUSION Our results suggest that this phenotype is due to cooperation between the activated TRalpha1 and WNT pathways. This is the first report describing the tumor-inducing function of TRalpha1 in the intestine.
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Affiliation(s)
- Elsa Kress
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS, INRA, Ecole Normale Supérieure de Lyon, Lyon, France
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Bouhallier F, Allioli N, Lavial F, Chalmel F, Perrard MH, Durand P, Samarut J, Pain B, Rouault JP. Role of miR-34c microRNA in the late steps of spermatogenesis. RNA 2010; 16:720-731. [PMID: 20150330 PMCID: PMC2844620 DOI: 10.1261/rna.1963810] [Citation(s) in RCA: 208] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2009] [Accepted: 12/23/2009] [Indexed: 05/27/2023]
Abstract
Spermatogenesis is a cyclic process in which diploid spermatogonia differentiate into haploid spermatozoa. This process is highly regulated, notably at the post-transcriptional level. MicroRNAs (miRNAs), single-stranded noncoding RNA molecules of about 20-25 nucleotides, are implicated in the regulation of many important biological pathways such as proliferation, apoptosis, and differentiation. We wondered whether miRNAs could play a role during spermatogenesis. The miRNA expression repertoire was tested in germ cells, and we present data showing that miR-34c was highly expressed only in these cells. Furthermore, our findings indicate that in male gonads, miR-34c expression is largely p53 independent in contrast to previous results showing a direct link in somatic cells between the miR-34 family and this tumor suppressor protein. In order to identify target genes involved in germinal lineage differentiation, we overexpressed miR-34c in HeLa cells, analyzed the transcriptome of these modified cells, and noticed a shift of the expression profile toward the germinal lineage. Recently, it has been shown that exogenous expression of Ddx4/Vasa in embryonic chicken stem cells (cESC) induces cESC reprogramming toward a germ cell fate. When we simultaneously expressed miR-34c in such cells, we could detect an up-regulation of germ cell-specific genes whereas the expression of other lineage specific markers remained unchanged. These data suggest that miR-34c could play a role by enhancing the germinal phenotype of cells already committed to this lineage.
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Affiliation(s)
- Frantz Bouhallier
- Ecole Normale Supérieure de Lyon, Institut de Génomique Fonctionnelle de Lyon (IGFL), Université Lyon1, CNRS UMR 5242, INRA UMR1288, F-69364 Lyon, Cedex 07, France
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Guyot R, Vincent S, Bertin J, Samarut J, Ravel-Chapuis P. The transforming acidic coiled coil (TACC1) protein modulates the transcriptional activity of the nuclear receptors TR and RAR. BMC Mol Biol 2010; 11:3. [PMID: 20078863 PMCID: PMC2822774 DOI: 10.1186/1471-2199-11-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2009] [Accepted: 01/15/2010] [Indexed: 11/23/2022] Open
Abstract
Background The transcriptional activity of Nuclear hormone Receptors (NRs) is regulated by interaction with coactivator or corepressor proteins. Many of these cofactors have been shown to have a misregulated expression or to show a subcellular mislocalization in cancer cell lines or primary tumors. Therefore they can be factors involved in the process of oncogenesis. Results We describe a novel NR coregulator, TACC1, which belongs to the Transforming Acidic Coiled Coil (TACC) family. The interaction of TACC1 with Thyroid Hormone Receptors (TR) and several other NRs has been shown in a yeast two-hybrid screen and confirmed by GST pulldown, colocalization and co-immunoprecipitation experiments. TACC1 interacts preferentially with unliganded NRs. In F9 cells, endogenous TACC1 localized in the chromatin-enriched fraction of the nucleus and interacted with Retinoid Acid Receptors (RARα) in the nucleus. TACC1 depletion in the cell led to decreased RARα and TRα ligand-dependent transcriptional activity and to delocalization of TR from the nucleus to the cytoplasm. Conclusions From these experimental studies we propose that TACC1 might be a scaffold protein building up a transcriptional complex around the NRs we studied. This function of TACC1 might account for its involvement in several forms of tumour development.
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Affiliation(s)
- Romain Guyot
- Institut de Génomique Fonctionnelle de Lyon, Universitéde Lyon, Université Lyon 1, CNRS, INRA, Ecole Normale Supérieure de Lyon, 46 allée d'Italie, 69364 Lyon Cedex 07, France
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Kress E, Samarut J, Plateroti M. Thyroid hormones and the control of cell proliferation or cell differentiation: paradox or duality? Mol Cell Endocrinol 2009; 313:36-49. [PMID: 19737599 DOI: 10.1016/j.mce.2009.08.028] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2009] [Revised: 08/07/2009] [Accepted: 08/31/2009] [Indexed: 11/22/2022]
Abstract
Amphibian metamorphosis perfectly illustrates a key paradox: thyroid hormones control diverse cellular processes depending on the tissue context. This point is also reinforced by a recent accumulation of evidence. For example, thyroid hormones and their nuclear receptor TRs have been described to function in different systems in synergy and/or in antagonism with other signaling pathways. This interaction helps explain their pleiotropic roles. This review summarizes the most important advances in this field, focusing in particular on the key action of thyroid hormones in controlling the balance between the processes of cell proliferation and cell differentiation in a few organs, with special attention paid to the intestine. We highlight similarities between the cellular and molecular events occurring during postnatal intestinal maturation at metamorphosis in amphibians, and comparable events observed at weaning in mice.
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Affiliation(s)
- Elsa Kress
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS, INRA, Ecole Normale Supérieure de Lyon, 46 allée d'Italie, 69364 Lyon Cedex 07, France
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Lavial F, Acloque H, Bachelard E, Nieto MA, Samarut J, Pain B. Ectopic expression of Cvh (Chicken Vasa homologue) mediates the reprogramming of chicken embryonic stem cells to a germ cell fate. Dev Biol 2009; 330:73-82. [PMID: 19324033 DOI: 10.1016/j.ydbio.2009.03.012] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2008] [Revised: 02/19/2009] [Accepted: 03/13/2009] [Indexed: 10/21/2022]
Abstract
When they are derived from blastodermal cells of the pre-primitive streak in vitro, the pluripotency of Chicken Embryonic Stem Cells (cESC) can be controlled by the cPouV and Nanog genes. These cESC can differentiate into derivatives of the three germ layers both in vitro and in vivo, but they only weakly colonize the gonads of host embryos. By contrast, non-cultured blastodermal cells and long-term cultured chicken primordial germ cells maintain full germline competence. This restriction in the germline potential of the cESC may result from either early germline determination in the donor embryos or it may occur as a result of in vitro culture. We are interested in understanding the genetic determinants of germline programming. The RNA binding protein Cvh (Chicken Vasa Homologue) is considered as one such determinant, although its role in germ cell physiology is still unclear. Here we show that the exogenous expression of Cvh, combined with appropriate culture conditions, induces cESC reprogramming towards a germ cell fate. Indeed, these cells express the Dazl, Tudor and Sycp3 germline markers, and they display improved germline colonization and adopt a germ cell fate when injected into recipient embryos. Thus, our results demonstrate that Vasa can drive ES cell differentiation towards the germ cell lineage, both in vitro and in vivo.
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Affiliation(s)
- Fabrice Lavial
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS, UMR 5242, INRA, Ecole Normale Supérieure de Lyon, France
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Pelletier P, Gauthier K, Sideleva O, Samarut J, Silva JE. Mice lacking the thyroid hormone receptor-alpha gene spend more energy in thermogenesis, burn more fat, and are less sensitive to high-fat diet-induced obesity. Endocrinology 2008; 149:6471-86. [PMID: 18719022 DOI: 10.1210/en.2008-0718] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Unable to activate brown adipose tissue (BAT) thermogenesis, alphaT3-receptor-deficient mice (Thra-0/0) are cold intolerant. Our objective was to investigate the impact on energy economy and mechanisms of the alternate facultative thermogenesis developed. Energy expenditure (oxygen and food consumption) is elevated in Thra-0/0 mice reared at room temperature. Such difference disappears at thermoneutrality (30 C) and expands as ambient temperature becomes colder (P < 0.001). Despite eating more, Thra-0/0 are leaner than wild-type (WT) mice (P < 0.01), whereas these, whether on chow or high-fat diet, gained more weight (g/d: 0.12 +/- 0.002 vs. 0.08 +/- 0.002 and 0.25 +/- 0.005 vs. 0.17 +/- 0.005, respectively) and adiposity than Thra-0/0 mice (P < 0.001). The respiratory quotient was lower in Thra-0/0 than WT mice (P < 0.001), after feeding or fasted, on chow or high-fat diet, indicating a preference for fat as fuel, which was associated with increased lipoprotein lipase (LPL) expression in skeletal muscle of Thra-0/0 mice but with no differences in gene expression in white adipose tissue. Type-2 deiodinase (D2) was increased in BAT and aerobic muscle of Thra-0/0 mice. This and liver D1 were increased by a high-fat diet in both genotypes, as also were serum T3 and T3/T4 ratio, but more in Thra-0/0 than WT mice (P < 0.001). Remarkably, when studied at thermoneutrality, genotype differences in weight and adiposity gain, respiratory quotient, D2, and LPL disappeared. Thus, disruption of BAT thermogenesis in Thra-0/0 mice activates an alternate facultative thermogenesis that is more energy demanding and associated with reduced fuel efficiency, leanness, increased capacity to oxidize fat, and relative resistance to diet-induced obesity, in all of which muscle LPL and deiodinases play a key role.
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Affiliation(s)
- Paula Pelletier
- Baystate Medical Center, Division of Endocrinology, Room S2620, 759 Chestnut Street, Springfield, Massachusetts 01199, USA
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Weinhofer I, Kunze M, Rampler H, Forss-Petter S, Samarut J, Plateroti M, Berger J. Distinct modulatory roles for thyroid hormone receptors TRα and TRβ in SREBP1-activated ABCD2 expression. Eur J Cell Biol 2008; 87:933-45. [DOI: 10.1016/j.ejcb.2008.08.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2008] [Revised: 08/18/2008] [Accepted: 08/20/2008] [Indexed: 01/23/2023] Open
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Kress E, Rezza A, Nadjar J, Samarut J, Plateroti M. The frizzled-related sFRP2 gene is a target of thyroid hormone receptor alpha1 and activates beta-catenin signaling in mouse intestine. J Biol Chem 2008; 284:1234-41. [PMID: 19001373 DOI: 10.1074/jbc.m806548200] [Citation(s) in RCA: 94] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The thyroid hormone receptor TRalpha1 regulates intestinal development and homeostasis by controlling epithelial proliferation in the crypts. This involves positive control of the Wnt/beta-catenin pathway. To further investigate the effect of thyroid hormone-TRalpha1 signaling on the intestinal epithelium proliferating compartment, we performed a comparative transcription profile analysis on laser microdissected crypt cells recovered from wild type animals with normal or perturbed hormonal status, as well as from TR knock-out mice. Statistical analysis and an in silico approach allowed us to identify 179 differentially regulated genes and to group them into organized functional networks. We focused on the "cell cycle/cell proliferation" network and, in particular, on the Frizzled-related protein sFRP2, whose expression was greatly increased in response to thyroid hormones. In vitro and in vivo analyses showed that the expression of sFRP2 is directly regulated by TRalpha1 and that it activates beta-catenin signaling via Frizzled receptors. Indeed, sFRP2 stabilizes beta-catenin, activates its target genes, and enhances cell proliferation. In conclusion, these new data, in conjunction with our previous results, indicate a complex interplay between TRalpha1 and components of the Wnt/beta-catenin pathway. Moreover, we describe in this study a novel mechanism of action of sFRP2, responsible for the activation of beta-catenin signaling.
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Affiliation(s)
- Elsa Kress
- Université de Lyon, Université Claude Bernard Lyon 1, Ecole Normale Supérieure de Lyon, INRA, CNRS, Institut de Génomique Fonctionnelle de Lyon, 69364 Lyon, France
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Lavial F, Acloque H, Bachelard E, Montillet G, Nieto A, Samarut J, Pain B. Molecular control of pluripotency and germ line competency in chicken embryonic stem cells. Cell Res 2008. [DOI: 10.1038/cr.2008.196] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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Canaple L, Beuf O, Armenean M, Hasserodt J, Samarut J, Janier M. Fast screening of paramagnetic molecules in zebrafish embryos by MRI. NMR Biomed 2008; 21:129-37. [PMID: 17516491 DOI: 10.1002/nbm.1169] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Zebrafish embryo is a well-established model used in many fields of modern experimental biology. We demonstrate that it provides a promising model platform for exploring fundamental MR aspects that can be used to screen and study active MR molecules before progressing to more complex living systems. Setting up a dedicated MRI methodology, we arrayed a large number of living embryos, which were microinjected at very early stages of development with different contrast agents. We also showed that MRI signal intensity correlates with the gadolinium content of zebrafish embryos. This allowed us to validate a new approach for MR compound screening. Using a specific surface coil of 5 mm inner diameter, we obtained for the first time high-spatial-resolution images at 7 T of living zebrafish embryos with a 47 microm isotropic voxel size with an acquisition time of 39 min. Finally, we discuss potential applications of this development: a viable in vivo assay for screening small pharmacological compounds; assessment of and tracking the action of molecules over time. Exploring in vivo biological activity, gene function analysis, and detailed characterization of disease processes in fish are natural extensions of these preliminary studies.
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Stavila V, Allali M, Canaple L, Stortz Y, Franc C, Maurin P, Beuf O, Dufay O, Samarut J, Janier M, Hasserodt J. Significant relaxivity gap between a low-spin and a high-spin iron(ii) complex of structural similarity: an attractive off–on system for the potential design of responsive MRI probes. NEW J CHEM 2008. [DOI: 10.1039/b715254j] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Kress E, Rezza A, Nadjar J, Samarut J, Plateroti M. The thyroid hormone receptor-alpha (TRalpha) gene encoding TRalpha1 controls deoxyribonucleic acid damage-induced tissue repair. Mol Endocrinol 2008; 22:47-55. [PMID: 17872380 PMCID: PMC5419624 DOI: 10.1210/me.2007-0278] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2007] [Accepted: 09/05/2007] [Indexed: 02/06/2023] Open
Abstract
The thyroid hormone (TH) controls, via its nuclear receptor, TH receptor-alpha1 (TRalpha1), intestinal crypt cell proliferation in the mouse. In order to understand whether this receptor also plays a role in intestinal regeneration after DNA damage, we applied a protocol of gamma-ray irradiation and monitored cell proliferation and apoptosis at several time points. In wild-type mice, the dose of 8 Gy induced cell cycle arrest and apoptosis in intestinal crypts a few hours after irradiation. This phenomenon reverted 48 h after irradiation. TRalpha(0/0) mutant mice displayed a constant low level of proliferating cells and a high apoptosis rate during the period of study. At the molecular level, in TRalpha(0/0) animals we observed a delay in the p53 phosphorylation induced by DNA damage. In our search for the expression of the protein kinases responsible for p53 phosphorylation upon irradiation, we have focused on DNA-dependent protein kinase catalytic subunit (DNA-PKcs). The number of cells expressing DNA-PKcs in crypts remained high 48 h after irradiation, specifically in TRalpha mutants. Altogether, in TRalpha(0/0) animals the rate of apoptosis in crypt cells remained high, apparently due to an elevated number of cells still presenting DNA damage. In conclusion, the TRalpha gene plays a role in crypt cell homeostasis by regulating the rate of cell renewal and apoptosis induced by DNA damage.
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Affiliation(s)
- Elsa Kress
- Université de Lyon, Université Claude Bernard Lyon 1, Ecole Normale Supérieure de Lyon, 69364 Lyon Cedex 07, France
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Lavial F, Acloque H, Bertocchini F, Macleod DJ, Boast S, Bachelard E, Montillet G, Thenot S, Sang HM, Stern CD, Samarut J, Pain B. The Oct4 homologue PouV and Nanog regulate pluripotency in chicken embryonic stem cells. Development 2007; 134:3549-63. [PMID: 17827181 DOI: 10.1242/dev.006569] [Citation(s) in RCA: 158] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Embryonic stem cells (ESC) have been isolated from pregastrulation mammalian embryos. The maintenance of their pluripotency and ability to self-renew has been shown to be governed by the transcription factors Oct4 (Pou5f1) and Nanog. Oct4 appears to control cell-fate decisions of ESC in vitro and the choice between embryonic and trophectoderm cell fates in vivo. In non-mammalian vertebrates, the existence and functions of these factors are still under debate, although the identification of the zebrafish pou2 (spg; pou5f1) and Xenopus Pou91 (XlPou91) genes, which have important roles in maintaining uncommitted putative stem cell populations during early development, has suggested that these factors have common functions in all vertebrates. Using chicken ESC (cESC), which display similar properties of pluripotency and long-term self-renewal to mammalian ESC, we demonstrated the existence of an avian homologue of Oct4 that we call chicken PouV (cPouV). We established that cPouV and the chicken Nanog gene are required for the maintenance of pluripotency and self-renewal of cESC. These findings show that the mechanisms by which Oct4 and Nanog regulate pluripotency and self-renewal are not exclusive to mammals.
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Affiliation(s)
- Fabrice Lavial
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS, INRA, Ecole Normale Supérieure de Lyon, France
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Bassett JHD, Williams AJ, Murphy E, Boyde A, Howell PGT, Swinhoe R, Archanco M, Flamant F, Samarut J, Costagliola S, Vassart G, Weiss RE, Refetoff S, Williams GR. A lack of thyroid hormones rather than excess thyrotropin causes abnormal skeletal development in hypothyroidism. Mol Endocrinol 2007; 22:501-12. [PMID: 17932107 DOI: 10.1210/me.2007-0221] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
By proposing TSH as a key negative regulator of bone turnover, recent studies in TSH receptor (TSHR) null mice challenged the established view that skeletal responses to disruption of the hypothalamic-pituitary-thyroid axis result from altered thyroid hormone (T(3)) action in bone. Importantly, this hypothesis does not explain the increased risk of osteoporosis in Graves' disease patients, in which circulating TSHR-stimulating antibodies are pathognomonic. To determine the relative importance of T(3) and TSH in bone, we compared the skeletal phenotypes of two mouse models of congenital hypothyroidism in which the normal reciprocal relationship between thyroid hormones and TSH was intact or disrupted. Pax8 null (Pax8(-/-)) mice have a 1900-fold increase in TSH and a normal TSHR, whereas hyt/hyt mice have a 2300-fold elevation of TSH but a nonfunctional TSHR. We reasoned these mice must display opposing skeletal phenotypes if TSH has a major role in bone, whereas they would be similar if thyroid hormone actions predominate. Pax8(-/-) and hyt/hyt mice both displayed delayed ossification, reduced cortical bone, a trabecular bone remodeling defect, and reduced bone mineralization, thus indicating that the skeletal abnormalities of congenital hypothyroidism are independent of TSH. Treatment of primary osteoblasts and osteoclasts with TSH or a TSHR-stimulating antibody failed to induce a cAMP response. Furthermore, TSH did not affect the differentiation or function of osteoblasts or osteoclasts in vitro. These data indicate the hypothalamic-pituitary-thyroid axis regulates skeletal development via the actions of T(3).
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Affiliation(s)
- J H Duncan Bassett
- Molecular Endocrinology Group, Medical Research Council Clinical Sciences Centre, Hammersmith Hospital, Du Cane Road, London, United Kingdom
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Quignodon L, Vincent S, Winter H, Samarut J, Flamant F. A Point Mutation in the Activation Function 2 Domain of Thyroid Hormone Receptor α1 Expressed after CRE-Mediated Recombination Partially Recapitulates Hypothyroidism. Mol Endocrinol 2007; 21:2350-60. [PMID: 17622582 DOI: 10.1210/me.2007-0176] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Thyroid hormones act directly on transcription by binding to TRalpha1, TRbeta1, and TRbeta2 nuclear receptors, regulating many aspects of postnatal development and homeostasis. To analyze precisely the implication of the widely expressed TRalpha1 isoform in this pleiotropic action, we have generated transgenic mice with a point mutation in the TRalpha1 coding sequence, which is expressed only after CRE/loxP-mediated DNA recombination. The amino acid change prevents interaction between TRalpha1 and histone acetyltransferase coactivators and the release of corepressors. Early expression of this dominant-negative receptor deeply affects postnatal development and adult homeostasis, recapitulating many aspects of congenital and adult hypothyroidism, except in tissues and cells where TRbeta1 and TRbeta2 are predominantly expressed. Both respective abundance and intrinsic properties of TRalpha1 and TRbeta1/2 seem to govern specificity of action.
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Affiliation(s)
- Laure Quignodon
- Institut de Génomique Fonctionnelle de Lyon, Université Lyon 1, Ecole Normale Supérieure de Lyon, Unité Mixte de Recherche, Centre National de la Recherche Scientifique 5242-Institut National de la Recherche Agronomique 1288, F-69364 Lyon, France
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Lerat E, Birot AM, Samarut J, Mey A. Maintenance in the Chicken Genome of the Retroviral-like cENS Gene Family Specifically Expressed in Early Embryos. J Mol Evol 2007; 65:215-27. [PMID: 17671751 DOI: 10.1007/s00239-007-9001-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2006] [Accepted: 05/18/2007] [Indexed: 02/05/2023]
Abstract
Embryonic stem (ES) cells are important developmental cells that appear very early during development and subsequently give rise to all the cell lineages of the future adult organism. In these cells a limited subset of transcription factors is expressed that are well conserved among species and essential for the fate of the stem cell. The transcriptome analysis of ES cells from chicken has revealed a gene family, cENS, that is specifically expressed in ES cells and in early embryos and is repressed during the differentiation process. This family is characterized by displaying retroviral structures and shares no homology with other species' genes. These characteristics are probably not restricted to the chicken genome and raise the question of whether similar genes are present and have been maintained in other species. We have examined the different copies of this gene in the sequenced chicken genome to investigate its dynamics and its evolution. We have distinguished two groups of cENS-related copies. The first group, resulting from recent transposition events, contains the transcribed ENS-1 and ENS-3 plus copies subjected to negative selection pressures. The second group contains degenerate copies that were integrated into the genome earlier. Comparison with copies previously isolated from three Galliformes showed that they are also subjected to selection pressures. We also detected numerous solo-LTRs containing the ENS-1 promoter that may control the expression of host genes. Taken together, these findings suggest a function sustained by a neogene of retroviral origin during the early stages of chicken development.
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Affiliation(s)
- Emmanuelle Lerat
- Laboratoire de Biométrie et Biologie Evolutive, Université de Lyon, Université Lyon 1, CNRS, UMR 5558, Villeurbanne, France.
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Quignodon L, Grijota-Martinez C, Compe E, Guyot R, Allioli N, Laperrière D, Walker R, Meltzer P, Mader S, Samarut J, Flamant F. A combined approach identifies a limited number of new thyroid hormone target genes in post-natal mouse cerebellum. J Mol Endocrinol 2007; 39:17-28. [PMID: 17601882 DOI: 10.1677/jme-06-0054] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Thyroid hormones act directly on gene transcription in the post-natal developing cerebellum, controlling neuronal, and glial cell differentiation. We have combined three experimental approaches to identify the target genes that are underlying this phenomenon: 1) a microarray analysis of gene expression to identify hormone responsive genes in the cerebellum of Pax8-/- mice, a transgenic mouse model of congenital hypothyroidism; 2) a similar microarray analysis on primary culture of cerebellum neurons; and 3) a bioinformatics screen of conserved putative-binding sites in the mouse genome. This identifies surprisingly a small set of target genes, which, for some of them, might be key regulators of cerebellum development and neuronal differentiation.
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Affiliation(s)
- Laure Quignodon
- Institut de Génomique Fonctionnelle de Lyon, Ecole Normale Supérieure de Lyon, Université de Lyon, UMR INRA CNRS 5242, IFR128 46 allée d'Italie, 69364 Lyon Cedex 07, France
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Bassett JHD, O'Shea PJ, Sriskantharajah S, Rabier B, Boyde A, Howell PGT, Weiss RE, Roux JP, Malaval L, Clement-Lacroix P, Samarut J, Chassande O, Williams GR. Thyroid Hormone Excess Rather Than Thyrotropin Deficiency Induces Osteoporosis in Hyperthyroidism. Mol Endocrinol 2007; 21:1095-107. [PMID: 17327419 DOI: 10.1210/me.2007-0033] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Thyrotoxicosis is an important but under recognized cause of osteoporosis. Recently, TSH deficiency, rather than thyroid hormone excess, has been suggested as the underlying cause. To investigate the molecular mechanism of osteoporosis in thyroid disease, we characterized the skeleton in mice lacking either thyroid hormone receptor alpha or beta (TRalpha(0/0), TRbeta-/-). Remarkably, in the presence of normal circulating thyroid hormone and TSH concentrations, adult TRalpha(0/0) mice had osteosclerosis accompanied by reduced osteoclastic bone resorption, whereas juveniles had delayed endochondral ossification with reduced bone mineral deposition. By contrast, adult TRbeta-/- mice with elevated TSH and thyroid hormone levels were osteoporotic with evidence of increased bone resorption, whereas juveniles had advanced ossification with increased bone mineral deposition. Analysis of T3 target gene expression revealed skeletal hypothyroidism in TRalpha(0/0) mice, but skeletal thyrotoxicosis in TRbeta-/- mice. These studies demonstrate that bone loss in thyrotoxicosis is independent of circulating TSH levels and mediated predominantly by TRalpha, thus identifying TRalpha as a novel drug target in the prevention and treatment of osteoporosis.
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Affiliation(s)
- J H Duncan Bassett
- Molecular Endocrinology Group, Division of Medicine and Medical Research Council (MRC) Clinical Sciences Centre, Imperial College London, Hammersmith Hospital, London W12 0NN, United Kingdom
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Flamant F, Baxter JD, Forrest D, Refetoff S, Samuels H, Scanlan TS, Vennström B, Samarut J. International Union of Pharmacology. LIX. The pharmacology and classification of the nuclear receptor superfamily: thyroid hormone receptors. Pharmacol Rev 2007; 58:705-11. [PMID: 17132849 DOI: 10.1124/pr.58.4.3] [Citation(s) in RCA: 121] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Affiliation(s)
- Frédéric Flamant
- Unité Mixte de Recherche, Centre National de la Recherche Scientifique 5665, Laboratoire Associé Institut National de la Recherche Agronomique 913, l'Institut Fédératif de Recherches 128, Lyon, France.
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Crozet C, Lezmi S, Flamant F, Samarut J, Baron T, Bencsik A. Peripheral circulation of the prion infectious agent in transgenic mice expressing the ovine prion protein gene in neurons only. J Infect Dis 2007; 195:997-1006. [PMID: 17330790 DOI: 10.1086/512085] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2006] [Accepted: 11/02/2006] [Indexed: 11/03/2022] Open
Abstract
BACKGROUND For prion diseases, even if a large body of evidence indicates that both the lymphoreticular system (LRS) and peripheral nerves are involved in scrapie neuroinvasion, the processes by which prions invade the central nervous system are only partially understood. METHODS Transgenic Tg(OvPrP4) mice, which express the ovine prion protein (PrP) gene under the rat neuron-specific enolase promoter on a knockout background, were used to study prion extracerebral circulation after scrapie prions were inoculated via the intracerebral (ic) and the intraperitoneal (ip) route. RESULTS Surprisingly, PrP(Sc) was detected in the spleens of mice inoculated ic with prions. Moreover, the absence of the ovine PrP(C) in nonneural tissue at the periphery did not stop neuroinvasion after ip challenge. Additionally, pilot studies performed in Tg(OvPrP4) mice that had undergone splenectomy before ic prion inoculation showed that the time course of the disease is delayed. CONCLUSIONS Given that these mice express the ovine PrP gene in neuronal cells but not in nonnervous tissue, our results suggest that PrP(C) expressed by cells of the LRS are not necessary for neuroinvasion or for their ability to accumulate PrP(Sc) and emphasize the importance of extracerebral circulation of PrP(C) or PrP(Sc) for the development of the disease.
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Affiliation(s)
- Carole Crozet
- Agence Francaise de Sécurité Sanitaire des Aliments, Unité Agents Transmissibles Non Conventionnels, Lyon, France
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Abstract
T3 regulates many physiological and developmental processes by binding to thyroid hormone receptors (TRs). This induces a conformational change of DNA-bound TRs that releases corepressors in favor of coactivators. The associated chromatin modifications induce polymerase II recruitment. Mouse genetic studies clarified the respective contribution of each receptor isoform and revealed the important activity of unliganded TRs. They also confirm the paradoxical negative regulation of some promoters by liganded TRs. Recent advances place these molecular events in a broader context of extra- and intracellular regulation: control of ligand availability, changes in the cell sensitivity to T3, nongenomic effects, and cross talks with other signaling pathways contribute to increase the diversity and complexity of thyroid hormones signaling. A promising novel class of TRs synthetic ligands, called STORMs (selective TR modulators), might allow for tissue- and promoter-specific interventions.
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Affiliation(s)
- Frederic Flamant
- Laboratory of Molecular Cell Biology, Unité Mixte de Recherche, Centre National de la Recherche Scientifique 5161, Institut National de la Recherche Agronomique 1237, France.
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