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Shi YB, Fu L, Tanizaki Y. Intestinal remodeling during Xenopus metamorphosis as a model for studying thyroid hormone signaling and adult organogenesis. Mol Cell Endocrinol 2024; 586:112193. [PMID: 38401883 PMCID: PMC10999354 DOI: 10.1016/j.mce.2024.112193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Revised: 02/15/2024] [Accepted: 02/20/2024] [Indexed: 02/26/2024]
Abstract
Intestinal development takes places in two phases, the initial formation of neonatal (mammals)/larval (anurans) intestine and its subsequent maturation into the adult form. This maturation occurs during postembryonic development when plasma thyroid hormone (T3) level peaks. In anurans such as the highly related Xenopus laevis and Xenopus tropicalis, the larval/tadpole intestine is drastically remodeled from a simple tubular structure to a complex, multi-folded adult organ during T3-dependent metamorphosis. This involved complete degeneration of larval epithelium via programmed cell death and de novo formation of adult epithelium, with concurrent maturation of the muscles and connective tissue. Here, we will summarize our current understanding of the underlying molecular mechanisms, with a focus on more recent genetic and genome-wide studies.
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Affiliation(s)
- Yun-Bo Shi
- Section on Molecular Morphogenesis, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, MD, 20892, USA.
| | - Liezhen Fu
- Section on Molecular Morphogenesis, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, MD, 20892, USA
| | - Yuta Tanizaki
- Section on Molecular Morphogenesis, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, MD, 20892, USA
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Tanizaki Y, Bao L, Shi YB. Steroid-receptor coactivator complexes in thyroid hormone-regulation of Xenopus metamorphosis. VITAMINS AND HORMONES 2023; 123:483-502. [PMID: 37717995 PMCID: PMC11274430 DOI: 10.1016/bs.vh.2023.02.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/11/2023]
Abstract
Anuran metamorphosis is perhaps the most drastic developmental change regulated by thyroid hormone (T3) in vertebrate. It mimics the postembryonic development in mammals when many organs/tissues mature into adult forms and plasma T3 level peaks. T3 functions by regulating target gene transcription through T3 receptors (TRs), which can recruit corepressor or coactivator complexes to target genes in the absence or presence of T3, respectively. By using molecular and genetic approaches, we and others have investigated the role of corepressor or coactivator complexes in TR function during the development of two highly related anuran species, the pseudo-tetraploid Xenopus laevis and diploid Xenopus tropicalis. Here we will review some of these studies that demonstrate a critical role of coactivator complexes, particularly those containing steroid receptor coactivator (SRC) 3, in regulating metamorphic rate and ensuring the completion of metamorphosis.
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Affiliation(s)
- Yuta Tanizaki
- Section on Molecular Morphogenesis, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, MD, United States
| | - Lingyu Bao
- Section on Molecular Morphogenesis, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, MD, United States
| | - Yun-Bo Shi
- Section on Molecular Morphogenesis, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, MD, United States.
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Shi YB, Shibata Y, Tanizaki Y, Fu L. The development of adult intestinal stem cells: Insights from studies on thyroid hormone-dependent anuran metamorphosis. VITAMINS AND HORMONES 2021; 116:269-293. [PMID: 33752821 DOI: 10.1016/bs.vh.2021.02.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Vertebrates organ development often takes place in two phases: initial formation and subsequent maturation into the adult form. This is exemplified by the intestine. In mouse, the intestine at birth has villus, where most differentiated epithelial cells are located, but lacks any crypts, where adult intestinal stem cells reside. The crypt is formed during the first 3 weeks after birth when plasma thyroid hormone (T3) levels are high. Similarly, in anurans, the intestine undergoes drastic remodeling into the adult form during metamorphosis in a process completely dependent on T3. Studies on Xenopus metamorphosis have revealed important clues on the formation of the adult intestine during metamorphosis. Here we will review our current understanding on how T3 induces the degeneration of larval epithelium and de novo formation of adult intestinal stem cells. We will also discuss the mechanistic conservations in intestinal development between anurans and mammals.
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Affiliation(s)
- Yun-Bo Shi
- Section on Molecular Morphogenesis, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, MD, United States.
| | - Yuki Shibata
- Section on Molecular Morphogenesis, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, MD, United States
| | - Yuta Tanizaki
- Section on Molecular Morphogenesis, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, MD, United States
| | - Liezhen Fu
- Section on Molecular Morphogenesis, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, MD, United States
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Kirfel P, Skaljac M, Grotmann J, Kessel T, Seip M, Michaelis K, Vilcinskas A. Inhibition of histone acetylation and deacetylation enzymes affects longevity, development, and fecundity in the pea aphid (Acyrthosiphon pisum). ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2020; 103:e21614. [PMID: 31498475 DOI: 10.1002/arch.21614] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2018] [Revised: 07/30/2018] [Accepted: 08/19/2019] [Indexed: 06/10/2023]
Abstract
Histone acetylation is an evolutionarily conserved epigenetic mechanism of eukaryotic gene regulation which is tightly controlled by the opposing activities of histone acetyltransferases (HATs) and histone deacetylases (HDACs). In insects, life-history traits such as longevity and fecundity are severely affected by the suppression of HAT/HDAC activity, which can be achieved by RNA-mediated gene silencing or the application of chemical inhibitors. We used both experimental approaches to investigate the effect of HAT/HDAC inhibition in the pea aphid (Acyrthosiphon pisum) a model insect often used to study complex life-history traits. The silencing of HAT genes (kat6b, kat7, and kat14) promoted survival or increased the number of offspring, whereas targeting rpd3 (HDAC) reduced the number of viviparous offspring but increased the number of premature nymphs, suggesting a role in embryogenesis and eclosion. Specific chemical inhibitors of HATs/HDACs showed a remarkably severe impact on life-history traits, reducing survival, delaying development, and limiting the number of offspring. The selective inhibition of HATs and HDACs also had opposing effects on aphid body weight. The suppression of HAT/HDAC activity in aphids by RNA interference or chemical inhibition revealed similarities and differences compared to the reported role of these enzymes in other insects. Our data suggest that gene expression in A. pisum is regulated by multiple HATs/HDACs, as indicated by the fitness costs triggered by inhibitors that suppress several of these enzymes simultaneously. Targeting multiple HATs or HDACs with combined effects on gene regulation could, therefore, be a promising approach to discover novel targets for the management of aphid pests.
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Affiliation(s)
- Phillipp Kirfel
- Fraunhofer Institute for Molecular Biology and Applied Ecology (IME), Branch for Bioresources, Giessen, Germany
| | - Marisa Skaljac
- Fraunhofer Institute for Molecular Biology and Applied Ecology (IME), Branch for Bioresources, Giessen, Germany
| | - Jens Grotmann
- Fraunhofer Institute for Molecular Biology and Applied Ecology (IME), Branch for Bioresources, Giessen, Germany
| | - Tobias Kessel
- Fraunhofer Institute for Molecular Biology and Applied Ecology (IME), Branch for Bioresources, Giessen, Germany
| | - Maximilian Seip
- Fraunhofer Institute for Molecular Biology and Applied Ecology (IME), Branch for Bioresources, Giessen, Germany
| | - Katja Michaelis
- Fraunhofer Institute for Molecular Biology and Applied Ecology (IME), Branch for Bioresources, Giessen, Germany
| | - Andreas Vilcinskas
- Fraunhofer Institute for Molecular Biology and Applied Ecology (IME), Branch for Bioresources, Giessen, Germany
- Department of Insect Biotechnology, Justus-Liebig University of Giessen, Giessen, Germany
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Functional Studies of Transcriptional Cofactors via Microinjection-Mediated Gene Editing in Xenopus. Methods Mol Biol 2019; 1874:507-524. [PMID: 30353533 DOI: 10.1007/978-1-4939-8831-0_29] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The anuran Xenopus laevis has been studied for decades as a model for vertebrate cell and developmental biology. More recently, the highly related species Xenopus tropicalis has offered the opportunity to carry out genetic studies due to its diploid genome as compared to the pseudo-tetraploid Xenopus laevis. Amphibians undergo a biphasic development: embryogenesis to produce a free-living tadpoles and subsequent metamorphosis to transform the tadpole to a frog. This second phase mimics the so-called postembryonic development in mammals when many organs/tissues mature into their adult form in the presence of high levels of plasma thyroid hormone (T3). The total dependence of amphibian metamorphosis on T3 offers a unique opportunity to study postembryonic development in vertebrates, especially with the recent development gene editing technologies that function in amphibians. Here, we first review the basic molecular understanding of the regulation of Xenopus metamorphosis by T3 and T3 receptors (TRs), and then describe a detailed method to use CRISPR to knock out the TR-coactivator SRC3 (steroid receptor coactivator 3), a histone acetyltransferase, in order to study its involvement in gene regulation by T3 in vivo and Xenopus development.
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Sachs LM, Buchholz DR. Frogs model man: In vivo thyroid hormone signaling during development. Genesis 2017; 55. [PMID: 28109053 DOI: 10.1002/dvg.23000] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Revised: 11/14/2016] [Accepted: 11/16/2016] [Indexed: 12/25/2022]
Abstract
Thyroid hormone (TH) signaling comprises TH transport across cell membranes, metabolism by deiodinases, and molecular mechanisms of gene regulation. Proper TH signaling is essential for normal perinatal development, most notably for neurogenesis and fetal growth. Knowledge of perinatal TH endocrinology needs improvement to provide better treatments for premature infants and endocrine diseases during gestation and to counteract effects of endocrine disrupting chemicals. Studies in amphibians have provided major insights to understand in vivo mechanisms of TH signaling. The frog model boasts dramatic TH-dependent changes directly observable in free-living tadpoles with precise and easy experimental control of the TH response at developmental stages comparable to fetal stages in mammals. The hormones, their receptors, molecular mechanisms, and developmental roles of TH signaling are conserved to a high degree in humans and amphibians, such that with respect to developmental TH signaling "frogs are just little people that hop." The frog model is exceptionally illustrative of fundamental molecular mechanisms of in vivo TH action involving TH receptors, transcriptional cofactors, and chromatin remodeling. This review highlights the current need, recent successes, and future prospects using amphibians as a model to elucidate molecular mechanisms and functional roles of TH signaling during post-embryonic development.
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Affiliation(s)
- Laurent M Sachs
- UMR 7221 CNRS, Muséum National d'histoire Naturelle, Dépt. Régulation, Développement et Diversité Moléculaire, Sorbonne Universités, Paris, 75005, France
| | - Daniel R Buchholz
- Department of Biological Sciences, University of Cincinnati, Cincinnati, Ohio, 45221
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Sun G, Roediger J, Shi YB. Thyroid hormone regulation of adult intestinal stem cells: Implications on intestinal development and homeostasis. Rev Endocr Metab Disord 2016; 17:559-569. [PMID: 27554108 DOI: 10.1007/s11154-016-9380-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Organ-specific adult stem cells are essential for organ homeostasis, tissue repair and regeneration. The formation of such stem cells often takes place during postembryonic development, a period around birth in mammals when plasma thyroid hormone concentration is high. The life-long self-renewal of the intestinal epithelium has made mammalian intestine a valuable model to study the function and regulation and adult stem cells. On the other hand, much less is known about how the adult intestinal stem cells are formed during vertebrate development. Here, we will review some recent progresses on this subject, focusing mainly on the formation of the adult intestine during Xenopus metamorphosis. We will discuss the role of thyroid hormone signaling pathway in the process and potential molecular conservations between amphibians and mammals as well as the implications in organ homeostasis and human diseases.
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Affiliation(s)
- Guihong Sun
- School of Basic Medical Sciences, Wuhan University, Wuhan, 430072, People's Republic of China
| | - Julia Roediger
- Section on Molecular Morphogenesis, Program in Cellular Regulation and Metabolism (PCRM), Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), 18 Library Dr., Bethesda, MD, 20892, USA
| | - Yun-Bo Shi
- Section on Molecular Morphogenesis, Program in Cellular Regulation and Metabolism (PCRM), Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), 18 Library Dr., Bethesda, MD, 20892, USA.
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Sun G, Fu L, Shi YB. Epigenetic regulation of thyroid hormone-induced adult intestinal stem cell development during anuran metamorphosis. Cell Biosci 2014; 4:73. [PMID: 25937894 PMCID: PMC4417507 DOI: 10.1186/2045-3701-4-73] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Accepted: 11/18/2014] [Indexed: 11/18/2022] Open
Abstract
Epigenetic modifications of histones are emerging as key factors in gene regulation by diverse transcription factors. Their roles during vertebrate development and pathogenesis are less clear. The causative effect of thyroid hormone (T3) on amphibian metamorphosis and the ability to manipulate this process for molecular and genetic studies have led to the demonstration that T3 receptor (TR) is necessary and sufficient for Xenopus metamorphosis, a process that resembles the postembryonic development (around birth) in mammals. Importantly, analyses during metamorphosis have provided some of the first in vivo evidence for the involvement of histone modifications in gene regulation by TR during vertebrate development. Furthermore, expression and functional studies suggest that various histone modifying epigenetic enzymes likely participate in multiple steps during the formation of adult intestinal stem cells during metamorphosis. The similarity between intestinal remodeling and the maturation of the mammalian intestine around birth when T3 levels are high suggests conserved roles for the epigenetic enzymes in mammalian adult intestinal stem cell development and/or proliferation.
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Affiliation(s)
- Guihong Sun
- School of Basic Medical Sciences, Wuhan University, Wuhan, 430072 P.R. China
| | - Liezhen Fu
- Section on Molecular Morphogenesis, Program in Cellular Regulation and Metabolism (PCRM), Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), 18 Library Dr, Bethesda, Maryland 20892 USA
| | - Yun-Bo Shi
- Section on Molecular Morphogenesis, Program in Cellular Regulation and Metabolism (PCRM), Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), 18 Library Dr, Bethesda, Maryland 20892 USA
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Otsuka S, Ishihara A, Yamauchi K. Ioxynil and Tetrabromobisphenol A Suppress Thyroid-Hormone-Induced Activation of Transcriptional Elongation Mediated by Histone Modifications and RNA Polymerase II Phosphorylation. Toxicol Sci 2014; 138:290-9. [DOI: 10.1093/toxsci/kfu012] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Shi YB, Matsuura K, Fujimoto K, Wen L, Fu L. Thyroid hormone receptor actions on transcription in amphibia: The roles of histone modification and chromatin disruption. Cell Biosci 2012; 2:42. [PMID: 23256597 PMCID: PMC3562205 DOI: 10.1186/2045-3701-2-42] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2012] [Accepted: 11/21/2012] [Indexed: 01/14/2023] Open
Abstract
Thyroid hormone (T3) plays diverse roles in adult organ function and during vertebrate development. The most important stage of mammalian development affected by T3 is the perinatal period when plasma T3 level peaks. Amphibian metamorphosis resembles this mammalian postembryonic period and is absolutely dependent on T3. The ability to easily manipulate this process makes it an ideal model to study the molecular mechanisms governing T3 action during vertebrate development. T3 functions mostly by regulating gene expression through T3 receptors (TRs). Studies in vitro, in cell cultures and reconstituted frog oocyte transcription system have revealed that TRs can both activate and repress gene transcription in a T3-dependent manner and involve chromatin disruption and histone modifications. These changes are accompanied by the recruitment of diverse cofactor complexes. More recently, genetic studies in mouse and frog have provided strong evidence for a role of cofactor complexes in T3 signaling in vivo. Molecular studies on amphibian metamorphosis have also revealed that developmental gene regulation by T3 involves histone modifications and the disruption of chromatin structure at the target genes as evidenced by the loss of core histones, arguing that chromatin remodeling is an important mechanism for gene activation by liganded TR during vertebrate development.
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Affiliation(s)
- Yun-Bo Shi
- Section on Molecular Morphogenesis, Program in Cellular Regulation and Metabolism (PCRM), Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, Maryland, 20892, USA.
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Grimaldi A, Buisine N, Miller T, Shi YB, Sachs LM. Mechanisms of thyroid hormone receptor action during development: lessons from amphibian studies. Biochim Biophys Acta Gen Subj 2012; 1830:3882-92. [PMID: 22565053 DOI: 10.1016/j.bbagen.2012.04.020] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2012] [Revised: 03/28/2012] [Accepted: 04/21/2012] [Indexed: 12/17/2022]
Abstract
BACKGROUND Thyroid hormone (TH) receptor (TR) plays critical roles in vertebrate development. However, the in vivo mechanism of TR action remains poorly explored. SCOPE OF REVIEW Frog metamorphosis is controlled by TH and mimics the postembryonic period in mammals when high levels of TH are also required. We review here some of the findings on the developmental functions of TH and TR and the associated mechanisms obtained from this model system. MAJOR CONCLUSION A dual function model for TR in Anuran development was proposed over a decade ago. That is, unliganded TR recruits corepressors to TH response genes in premetamorphic tadpoles to repress these genes and prevent premature metamorphic changes. Subsequently, when TH becomes available, liganded TR recruits coactivators to activate these same genes, leading to metamorphic changes. Over the years, molecular and genetic approaches have provided strong support for this model. Specifically, it has been shown that unliganded TR recruits histone deacetylase containing corepressor complexes during larval stages to control metamorphic timing, while liganded TR recruits multiple histone modifying and chromatin remodeling coactivator complexes during metamorphosis. These complexes can alter chromatin structure via nucleosome position alterations or eviction and histone modifications to contribute to the recruitment of transcriptional machinery and gene activation. GENERAL SIGNIFICANCE The molecular mechanisms of TR action in vivo as revealed from studies on amphibian metamorphosis are very likely applicable to mammalian development as well. These findings provide a new perspective for understanding the diverse effects of TH in normal physiology and diseases caused by TH dysfunction. This article is part of a Special Issue entitled Thyroid hormone signalling.
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Affiliation(s)
- Alexis Grimaldi
- Muséum National d'Histoire Naturelle, Dépt. Régulation Développement et Diversité Moléculaire, UMR7221 CNRS, Evolution des Régulations Endocriniennes, Section on thyroid hormone receptor function and mechanism of action, 57 rue Cuvier, 75231 Paris cedex 05, France
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Morvan-Dubois G, Demeneix BA, Sachs LM. Xenopus laevis as a model for studying thyroid hormone signalling: from development to metamorphosis. Mol Cell Endocrinol 2008; 293:71-9. [PMID: 18657589 DOI: 10.1016/j.mce.2008.06.012] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2008] [Revised: 06/03/2008] [Accepted: 06/12/2008] [Indexed: 11/18/2022]
Abstract
Amphibian metamorphosis is a well-established model for dissecting the mechanisms underlying thyroid hormone (TH) action. How the pro-hormone, T(4), the active form, T(3), the deiodinases and the nuclear receptors (TRs) contribute to metamorphosis in Xenopus has been extensively investigated. Our recent work has concentrated on two key ideas in TH signalling in Xenopus: first, that there could be active roles for both liganded and unliganded receptors, and second, that ligand availability is a determining factor orchestrating these actions and is tightly controlled in target tissues. Recently, we addressed these questions at stages preceding metamorphosis, i.e. during embryogenesis, before differentiation of a functional thyroid gland. We show that repression by unliganded TR is essential to craniofacial and eye development during early development and that at these stages all three deiodinases are active. These results open new perspectives on the potential roles of TH signalling during embryogenesis.
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Chen W, Obara M, Ishida Y, Suzuki KI, Yoshizato K. Characterization of histone lysine-specific demethylase in relation to thyroid hormone-regulated anuran metamorphosis. Dev Growth Differ 2007; 49:325-34. [PMID: 17501908 DOI: 10.1111/j.1440-169x.2007.00927.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The thyroid hormone receptor (THR) is a member of the nuclear transcription factor and plays a central role in regulating anuran metamorphosis. Previous studies with mammalian cells have suggested that THR is involved in chromatin remodeling through histone methylation. In the present study, we cloned cDNA of lysine-specific demethylase gene, xLSD1, from Xenopus laevis and examined its expression in relation to metamorphosis. Overexpression of xLSD1 in A6 cells, a Xenopus laevis cell line, resulted in the decrease of methylation status of lysine residues of histone H3, indicating that the protein of cloned xLSD1 was functionally active. The expression of LSD1 at mRNA levels was up-regulated in the body skin and the intestine during natural and thyroid hormone-induced metamorphosis. Larval epidermal basal cells and intestinal epithelial cells at the premetamorphic stage were identified as the xLSD1-expressing cells. At the metamorphic climax stage the progenitor cells of adult epidermal basal cells also expressed xLSD1, whereas those of the adult intestinal epithelial cells did not. We propose that LSD1 participates in the regulation of metamorphosis through THR- or another transcriptional factor-induced chromatin remodeling.
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Affiliation(s)
- Wen Chen
- Department of Biological Science, Graduate School of Science, Hiroshima University, Kagamiyama 1-3-1, Higashihiroshima, Hiroshima 739-8526, Japan
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Menegola E, Di Renzo F, Broccia ML, Giavini E. Inhibition of histone deacetylase as a new mechanism of teratogenesis. ACTA ACUST UNITED AC 2007; 78:345-53. [PMID: 17315247 DOI: 10.1002/bdrc.20082] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Histone deacetylases (HDACs) are nuclear and cytoplasmic enzymes that deacetylate a number of substrates, of which histones are the best known and described in the literature. HDACs are present in eukaryotic and bacteria cells, and are fundamental for a number of cellular functions, including correct gene expression. Surprisingly, only up to 20% of the whole genome is controlled by HDACs, but key processes for survival, proliferation, and differentiation have been strictly linked to HDAC enzyme functioning. The use of HDAC inhibitors (HDACi) has been proposed for the treatment of neoplastic diseases. Their effectiveness has been suggested for a number of liquid and solid tumors, particularly acute promyelocytic leukemia (APL). The role of HDACs in embryo development is currently under investigation. Published data indicate knockout phenotype analysis to be of particular interest, in which a number of HDACs play a key role during development. Little data have been published on the effects of HDACi on embryonic development, although for valproic acid (VPA), literature from the 1980s described its teratogenic effects in experimental animals and humans. To date, all tested HDACi have shown teratogenic effects similar to those described for VPA when tested in zebrafish, Xenopus laevis, and mice. HDACs were also able to alter embryo development in invertebrates and plants. A model, similar to that proposed in APL, involving retinoic acid receptors (RAR) and tissue specific Hox gene expression, is suggested to explain the HDAC effects on embryo development.
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Affiliation(s)
- Elena Menegola
- Department of Biology, University of Milan, Milan, Italy.
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Havis E, Le Mevel S, Morvan Dubois G, Shi DL, Scanlan TS, Demeneix BA, Sachs LM. Unliganded thyroid hormone receptor is essential for Xenopus laevis eye development. EMBO J 2006; 25:4943-51. [PMID: 17006540 PMCID: PMC1618110 DOI: 10.1038/sj.emboj.7601356] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2006] [Accepted: 08/23/2006] [Indexed: 01/05/2023] Open
Abstract
Thyroid hormone receptors generally activate transcription of target genes in the presence of thyroid hormone (T(3)) and repress their transcription in its absence. Here, we investigated the role of unliganded thyroid hormone receptor (TR) during vertebrate development using an amphibian model. Previous studies led to the hypothesis that before production of endogenous T(3), the presence of unliganded receptor is essential for premetamorphic tadpole growth. To test this hypothesis, we generated a Xenopus laevis TR beta mutant construct ineffective for gene repression owing to impaired corepressor NCoR recruitment. Overexpression by germinal transgenesis of the mutant receptor leads to lethality during early development with numerous defects in cranio-facial and eye development. These effects correlate with TR expression profiles at these early stages. Molecular analysis of transgenic mutants reveals perturbed expression of genes involved in eye development. Finally, treatment with iopanoic acid or NH-3, modulators of thyroid hormone action, leads to abnormal eye development. In conclusion, the data reveal a role of unliganded TR in eye development.
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Affiliation(s)
- Emmanuelle Havis
- UMR5166 CNRS, USM-501 Muséum National d'Histoire Naturelle, Dépt. Régulation, Développement et Diversité Moléculaire, Paris, France
| | - Sébastien Le Mevel
- UMR5166 CNRS, USM-501 Muséum National d'Histoire Naturelle, Dépt. Régulation, Développement et Diversité Moléculaire, Paris, France
| | - Ghislaine Morvan Dubois
- UMR5166 CNRS, USM-501 Muséum National d'Histoire Naturelle, Dépt. Régulation, Développement et Diversité Moléculaire, Paris, France
| | - De-Li Shi
- UMR7622 CNRS, Laboratoire de Biologie du Développement, Université Pierre et Marie Curie, Paris VI, Paris, France
| | - Thomas S Scanlan
- Department of Pharmaceutical Chemistry, University of California-San Francisco, San Francisco, CA, USA
| | - Barbara A Demeneix
- UMR5166 CNRS, USM-501 Muséum National d'Histoire Naturelle, Dépt. Régulation, Développement et Diversité Moléculaire, Paris, France
| | - Laurent M Sachs
- UMR5166 CNRS, USM-501 Muséum National d'Histoire Naturelle, Dépt. Régulation, Développement et Diversité Moléculaire, Paris, France
- UMR5166 CNRS, USM-501 Muséum National d'Histoire Naturelle, Dépt. Régulation, Développement et Diversité Moléculaire, CP 33, 7 rue Cuvier, 75231 Paris cedex 05, France. Tel.: +33 1 40 79 36 04; Fax: +33 1 40 79 36 18; E-mail:
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16
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Puppin C, D'Aurizio F, D'Elia AV, Cesaratto L, Tell G, Russo D, Filetti S, Ferretti E, Tosi E, Mattei T, Pianta A, Pellizzari L, Damante G. Effects of histone acetylation on sodium iodide symporter promoter and expression of thyroid-specific transcription factors. Endocrinology 2005; 146:3967-74. [PMID: 15919754 DOI: 10.1210/en.2005-0128] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Inhibitors of histone deacetylases (HDACs) activate the sodium iodide symporter (NIS) expression in thyroid tumor cells. In this study, mechanisms accounting for these effects were investigated. Various human thyroid tumor cell lines (ARO, BCPAP, FRO, TPC-1) were treated with the HDAC inhibitors Na butyrate (NaB) and tricostatin A (TSA), and the effects on the expression of NIS and several thyroid-specific transcription factors together with the activity of NIS promoter were evaluated. TSA and NaB increased NIS mRNA levels in all cell lines. Among thyroid-specific transcription factors, only expression of PAX8 in ARO cells was increased. Down-regulation of thyroid-specific transcription factor-1 expression was observed in BCPAP and TPC-1 cell lines. Thyroid-specific transcription factor-2 mRNA was reduced in FRO, BCPAP, and TPC-1 cells. Histone acetylation had no significant effects on HEX expression. Altogether, these data indicate that the increase of NIS expression is not mediated by modification of expression of thyroid-specific transcription factors. Accordingly, in transfection experiments performed in the HeLa cell line (which does not express thyroid-specific transcription factors), treatment with TSA and NaB increased NIS promoter activity. Stimulation of NIS promoter activity was also obtained by overexpressing histone acetylating proteins pCAF and p300 in HeLa cells. Conversely, overexpression of the HDAC 1 enzyme inhibited basal activity of the NIS promoter. Effects of TSA and NaB on NIS expression were also evaluated in nonthyroid cell lines MCF-7, Hep-G2, and SAOS-2. In all cell lines TSA and NaB greatly increased NIS mRNA levels. We concluded that control of NIS expression by inhibition of HDAC appears not to be mediated by cell-specific mechanisms, suggesting it as a potential strategy to induce radioiodine sensitivity in different human tumors.
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Affiliation(s)
- Cinzia Puppin
- Dipartimento di Scienze e Tecnologie Biomediche, Policlinico Universitario di Udine, Piazzale Kolbe 1, 33100 Udine, Italy
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17
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Whetstine JR, Ceron J, Ladd B, Dufourcq P, Reinke V, Shi Y. Regulation of tissue-specific and extracellular matrix-related genes by a class I histone deacetylase. Mol Cell 2005; 18:483-90. [PMID: 15893731 DOI: 10.1016/j.molcel.2005.04.006] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2005] [Revised: 02/17/2005] [Accepted: 04/08/2005] [Indexed: 10/25/2022]
Abstract
Class I histone deacetylases (HDACs) repress transcription by deacetylating histones and have been shown to play crucial roles in mouse, Xenopus, zebrafish, and C. elegans development. To identify the molecular networks regulated by a class I HDAC in a multicellular organism, we carried out a global gene expression profiling study using C. elegans embryos, and identified tissue-specific and extracellular matrix (ECM)-related genes as major HDA-1 targets. Ectopic expression of HDA-1 or C. elegans cystatin, an HDA-1 target identified from the microarray, significantly perturbed mammalian cell invasion. Similarly, RNAi depletion or overexpression of human HDAC-1 also affected cell migration. These findings suggest that HDA-1/HDAC-1 may play a critical, evolutionarily conserved role in regulating the extracellular microenvironment. Because human HDACs are targets for cancer therapy, these findings have significant implications in cancer treatment.
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Paul BD, Fu L, Buchholz DR, Shi YB. Coactivator recruitment is essential for liganded thyroid hormone receptor to initiate amphibian metamorphosis. Mol Cell Biol 2005; 25:5712-24. [PMID: 15964825 PMCID: PMC1156993 DOI: 10.1128/mcb.25.13.5712-5724.2005] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2004] [Revised: 10/19/2004] [Accepted: 03/25/2005] [Indexed: 11/20/2022] Open
Abstract
Thyroid hormone receptors (TRs) can repress or activate target genes depending on the absence or presence of thyroid hormone (T3), respectively. This hormone-dependent gene regulation is mediated by recruitment of co-repressors in the absence of T3 and coactivators in its presence. Many TR-interacting coactivators have been characterized in vitro. In comparison, few studies have addressed the developmental roles of these cofactors in vivo. We have investigated the role of coactivators in transcriptional activation by TR during postembryonic tissue remodeling by using amphibian metamorphosis as a model system. We have previously shown that steroid receptor coactivator 3 (SRC3) is expressed and upregulated during metamorphosis, suggesting a role in gene regulation by liganded TR. Here, we have generated transgenic tadpoles expressing a dominant negative form of SRC3 (F-dnSRC3). The transgenic tadpoles exhibited normal growth and development throughout embryogenesis and premetamorphic stages. However, transgenic expression of F-dnSRC3 inhibits essentially all aspects of T3-induced metamorphosis, as well as natural metamorphosis, leading to delayed or arrested metamorphosis or the formation of tailed frogs. Molecular analysis revealed that F-dnSRC3 functioned by blocking the recruitment of endogenous coactivators to T3 target genes without affecting corepressor release, thereby preventing the T3-dependent gene regulation program responsible for tissue transformations during metamorphosis. Our studies thus demonstrate that coactivator recruitment, aside from corepressor release, is required for T3 function in development and further provide the first example where a specific coactivator-dependent gene regulation pathway by a nuclear receptor has been shown to underlie specific developmental events.
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Affiliation(s)
- Bindu Diana Paul
- Laboratory of Gene Regulation and Development, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892, USA
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Pillai R, Coverdale LE, Dubey G, Martin CC. Histone deacetylase 1 (HDAC-1) required for the normal formation of craniofacial cartilage and pectoral fins of the zebrafish. Dev Dyn 2005; 231:647-54. [PMID: 15376317 DOI: 10.1002/dvdy.20168] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Histone deacetylases interact with nucleosomes to facilitate the formation of transcriptionally repressed chromatin. In the present study, we show that histone deacetylase 1 (hdac-1) is expressed throughout embryonic development of the zebrafish. The expression of hdac-1 is ubiquitous in early embryos (2-16 hr postfertilization), but at later stages (36 and 48 hr postfertilization), it is primarily restricted to the branchial arches, fin bud mesenchyme, and hindbrain. We report the phenotypes of hdac-1 homozygous mutant embryos and embryos injected with an hdac-1 antisense morpholino. These embryos possess a complex phenotype affecting several embryonic structures. We observed developmental abnormalities in the heart and neural epithelial structures, including the retina and the loss of craniofacial cartilage and pectoral fins.
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Affiliation(s)
- Renjitha Pillai
- Department of Biology, University of Ottawa, Ottawa, Ontario, Canada K1N 6N5
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Sachs LM. Corepressor requirement and thyroid hormone receptor function during Xenopus development. VITAMINS AND HORMONES 2004; 68:209-30. [PMID: 15193456 DOI: 10.1016/s0083-6729(04)68007-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The biologic role of hormonal activation of nuclear receptors is well established. Only recently, however, has the biologic significance of repression begun to be appreciated. Amphibian metamorphosis is marked by dramatic thyroid hormone induced changes, including de novo morphogenesis, tissue remodeling, and organ resorption through programmed cell death. These changes involve cascades of gene regulation initiated by 3,5,3'-triiodothyronine (T(3)). T(3) functions by regulating gene expression through thyroid hormone receptor (TR). TRs are DNA-binding transcription factors that belong to the steroid hormone receptor superfamily. In the absence of a ligand, TRs can repress gene expression by recruiting corepressor complexes, whereas liganded TRs recruit coactivator complexes for gene activation. Corepressor and coactivator complexes induce chromatin remodeling to mediate TR regulation of transcription. The mechanisms of TR action permit a dual function for TRs during development. In premetamorphic tadpoles, when TRs are expressed and T(3) levels are barely detectable, unliganded TRs repress transcription through corepressor recruitment. This TR-mediated repression of target genes is critical for proper larval development, allowing tadpole growth and acquisition of metamorphic competence. In contrast, during metamorphosis, endogenous T(3) causes TRs to activate gene expression, leading to tadpole transformation. Several results also support a role for corepressors during metamorphosis. Corepressor targeted functions, however, are still speculative but may again involve TRs. The requirement of active gene repression at different stages during amphibian development establishes an important biologic role for corepressors.
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Affiliation(s)
- Laurent M Sachs
- Département Régulations, Développement et Diversité Moléculaire, USM 501 Muséum National d'Histoire Naturelle, UMR-5166 CNRS, 75231 Paris cedex 05, France
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Buchholz DR, Hsia SCV, Fu L, Shi YB. A dominant-negative thyroid hormone receptor blocks amphibian metamorphosis by retaining corepressors at target genes. Mol Cell Biol 2003; 23:6750-8. [PMID: 12972595 PMCID: PMC193935 DOI: 10.1128/mcb.23.19.6750-6758.2003] [Citation(s) in RCA: 109] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The total dependence of amphibian metamorphosis on thyroid hormone (T(3)) provides a unique vertebrate model for studying the molecular mechanism of T(3) receptor (TR) function in vivo. In vitro transcription and developmental expression studies have led to a dual function model for TR in amphibian development, i.e., TRs act as transcriptional repressors in premetamorphic tadpoles and as activators during metamorphosis. We examined molecular mechanisms of TR action in T3-induced metamorphosis by using dominant-negative receptors (dnTR) ubiquitously expressed in transgenic Xenopus laevis. We showed that T(3)-induced activation of T(3) target genes and morphological changes are blocked in dnTR transgenic animals. By using chromatin immunoprecipitation, we show that dnTR bound to target promoters, which led to retention of corepressors and continued histone deacetylation in the presence of T(3). These results thus provide direct in vivo evidence for the first time for a molecular mechanism of altering gene expression by a dnTR. The correlation between dnTR-mediated gene repression and inhibition of metamorphosis also supports a key aspect of the dual function model for TR in development: during T(3)-induced metamorphosis, TR functions as an activator via release of corepressors and promotion of histone acetylation and gene activation.
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Affiliation(s)
- Daniel R Buchholz
- Unit on Molecular Morphogenesis, Laboratory of Gene Regulation and Development, National Institute for Child Health and Human Development, Bethesda, Maryland 20892-5431, USA
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Utoh R, Shigenaga S, Watanabe Y, Yoshizato K. Platelet-derived growth factor signaling as a cue of the epithelial-mesenchymal interaction required for anuran skin metamorphosis. Dev Dyn 2003; 227:157-69. [PMID: 12761844 DOI: 10.1002/dvdy.10302] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
The anuran remodels the larval skin into the adult counterpart during metamorphosis. The construction of the precursor of adult epidermis (preadult epidermis) in Xenopus laevis larvae was coordinated with the development of the secondary connective tissue (s-ct) underneath the basement membrane, suggesting that the epithelial-mesenchymal interaction plays a critical role in the metamorphic conversion of the larval skin. mRNAs of platelet-derived growth factor A (PDGF-A) and PDGF receptor (PDGFR) -alpha were markedly up-regulated in the skin during spontaneous and thyroid hormone (TH) -induced metamorphosis. In situ hybridization experiments identified preadult epidermal basal cells and fibroblasts in developing subepidermal connective tissues at the late prometamorphic stage as PDGF-A and PDGFR-alpha mRNA-expressing cells, respectively. We developed an in vitro model of larval skin that was remodeled to the adult skin under the influence of TH. The presence of either of AG1296, a specific inhibitor of PDGFR tyrosine kinase autophosphorylation, or an excess of recombinant proteins of the soluble extracellular domain of PDGFR-alpha inhibited the following TH-induced processes, the proliferation of adult basal cells, the terminal differentiation of adult basal cells, and the activation of subepidermal fibroblasts. However, the inhibitors did not inhibit the TH-induced proliferation of preadult basal cells. We concluded that PDGF/PDGFR signaling is one of the prime cues in the epithelial-mesenchymal interaction required for the metamorphic skin remodeling.
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Affiliation(s)
- Rie Utoh
- Laboratory of Developmental Biology, Department of Biological Science, Graduate School of Science, Hiroshima University, Kagamiyama, Higashihiroshima, Japan
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Weston AD, Blumberg B, Underhill TM. Active repression by unliganded retinoid receptors in development: less is sometimes more. J Cell Biol 2003; 161:223-8. [PMID: 12719467 PMCID: PMC2172895 DOI: 10.1083/jcb.200211117] [Citation(s) in RCA: 100] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The retinoid receptors have major roles throughout development, even in the absence of ligand. Here, we summarize an emerging theme whereby gene repression, mediated by unliganded retinoid receptors, can dictate cell fate. In addition to activating transcription, retinoid receptors actively repress gene transcription by recruiting cofactors that promote chromatin compaction. Two developmental processes for which gene silencing by the retinoid receptors is essential are head formation in Xenopus and skeletal development in the mouse. Inappropriate repression, by oncogenic retinoic acid (RA)**Abbreviations used in this paper: APL, acute promyelocytic leukemia; dnRARalpha, dominant-negative version of the RARalpha; E, embryonic age; HDAC, histone deacetylase; LCoR, ligand-dependent corepressor; NCoR, nuclear receptor corepressor; RA, retinoic acid; RAR, RA receptor; RARE, RXR homodimer bound to bipartite response element; RXR, retinoid X receptor; TSA, trichostatin A; CYP26, cytochrome p450, 26; TR, thyroid hormone receptor. receptor (RAR) fusion proteins, blocks myeloid differentiation leading to a rare form of leukemia. Our current understanding of the developmental role of retinoid repression and future perspectives in this field are discussed.
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Affiliation(s)
- Andrea D Weston
- Institute for Systems Biology, 1441 N. 34th St., Seattle, WA 98103, USA.
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Sachs LM, Jones PL, Havis E, Rouse N, Demeneix BA, Shi YB. Nuclear receptor corepressor recruitment by unliganded thyroid hormone receptor in gene repression during Xenopus laevis development. Mol Cell Biol 2002; 22:8527-38. [PMID: 12446772 PMCID: PMC139868 DOI: 10.1128/mcb.22.24.8527-8538.2002] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Thyroid hormone receptors (TR) act as activators of transcription in the presence of the thyroid hormone (T(3)) and as repressors in its absence. While many in vitro approaches have been used to study the molecular mechanisms of TR action, their physiological relevance has not been addressed. Here we investigate how TR regulates gene expression during vertebrate postembryonic development by using T(3)-dependent amphibian metamorphosis as a model. Earlier studies suggest that TR acts as a repressor during premetamorphosis when T(3) is absent. We hypothesize that corepressor complexes containing the nuclear receptor corepressor (N-CoR) are key factors in this TR-dependent gene repression, which is important for premetamorphic tadpole growth. To test this hypothesis, we isolated Xenopus laevis N-CoR (xN-CoR) and showed that it was present in pre- and metamorphic tadpoles. Using a chromatin immunoprecipitation assay, we demonstrated that xN-CoR was recruited to the promoters of T(3) response genes during premetamorphosis and released upon T(3) treatment, accompanied by a local increase in histone acetylation. Furthermore, overexpression of a dominant-negative N-CoR in tadpole tail muscle led to increased transcription from a T(3)-dependent promoter. Our data indicate that N-CoR is recruited by unliganded TR to repress target gene expression during premetamorphic animal growth, an important process that prepares the tadpole for metamorphosis.
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Affiliation(s)
- Laurent M Sachs
- Unit on Molecular Morphogenesis, Laboratory of Gene Regulation and Development, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892-5431, USA.
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