1
|
Yuan N, Su Y, Gao Y, Yang B, Zhang T, Wang Q, Zhang D, Shi L, Jiao A, Lei L, Sun L, Zhang B. Med1 controls thymic T-cell migration into lymph node through enhancer-based Foxo1-Klf2 transcription program. Eur J Immunol 2024:e2350887. [PMID: 39072704 DOI: 10.1002/eji.202350887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 07/02/2024] [Accepted: 07/09/2024] [Indexed: 07/30/2024]
Abstract
The migration is the key step for thymic T cells to enter circulation and then lymph nodes (LNs), essential for future immune surveillance. Although promoter-based transcriptional regulation through Foxo1, Klf2, Ccr7, and Sell regulates T-cell migration, it remains largely unexplored whether and how enhancers are involved in this process. Here we found that the conditional deletion of Med1, a component of the mediator complex and a mediator between enhancers and RNA polymerase II, caused a reduction of both CD4+ and CD8+ T cells in LNs, as well as a decrease of CD8+ T cells in the spleen. Importantly, Med1 deletion hindered the migration of thymic αβT cells into the circulation and then into LNs, accompanied by the downregulation of KLF2, CCR7, and CD62L. Mechanistically, Med1 promotes Klf2 transcription by facilitating Foxo1 binding to the Klf2 enhancer. Furthermore, forced expression of Klf2 rescued Ccr7 and Sell expression, as well as αβT-cell migration into LNs. Collectively, our study unveils a crucial role for Med1 in regulating the enhancer-based Foxo1-Klf2 transcriptional program and the migration of αβT cells into LNs, providing valuable insights into the molecular mechanisms underlying T-cell migration.
Collapse
Affiliation(s)
- Ning Yuan
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi'an Jiaotong University, Xi'an, Shaanxi Province, China
- Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi Province, China
| | - Yanhong Su
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi'an Jiaotong University, Xi'an, Shaanxi Province, China
- Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi Province, China
| | - Yang Gao
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi'an Jiaotong University, Xi'an, Shaanxi Province, China
- Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi Province, China
- Department of Kidney Transplantation, Hospital of Nephropathy, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi Province, China
- Institute of Organ Transplantation, Xi'an Jiaotong University, Xi'an, Shaanxi Province, China
| | - Biao Yang
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi'an Jiaotong University, Xi'an, Shaanxi Province, China
- Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi Province, China
| | - Tianzhe Zhang
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi'an Jiaotong University, Xi'an, Shaanxi Province, China
- Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi Province, China
- Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Xi'an, Shaanxi Province, China
- Basic and Translational Research Laboratory of Immune Related Diseases, Xi'an, Shaanxi Province, China
| | - Qianhao Wang
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi'an Jiaotong University, Xi'an, Shaanxi Province, China
- Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi Province, China
- Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Xi'an, Shaanxi Province, China
- Basic and Translational Research Laboratory of Immune Related Diseases, Xi'an, Shaanxi Province, China
| | - Dan Zhang
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi'an Jiaotong University, Xi'an, Shaanxi Province, China
- Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi Province, China
- Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Xi'an, Shaanxi Province, China
- Basic and Translational Research Laboratory of Immune Related Diseases, Xi'an, Shaanxi Province, China
| | - Lin Shi
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi'an Jiaotong University, Xi'an, Shaanxi Province, China
- Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi Province, China
- Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Xi'an, Shaanxi Province, China
- Basic and Translational Research Laboratory of Immune Related Diseases, Xi'an, Shaanxi Province, China
| | - Anjun Jiao
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi'an Jiaotong University, Xi'an, Shaanxi Province, China
- Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi Province, China
- Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Xi'an, Shaanxi Province, China
- Basic and Translational Research Laboratory of Immune Related Diseases, Xi'an, Shaanxi Province, China
| | - Lei Lei
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi'an Jiaotong University, Xi'an, Shaanxi Province, China
- Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi Province, China
- Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Xi'an, Shaanxi Province, China
- Basic and Translational Research Laboratory of Immune Related Diseases, Xi'an, Shaanxi Province, China
| | - Lina Sun
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi'an Jiaotong University, Xi'an, Shaanxi Province, China
- Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi Province, China
- Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Xi'an, Shaanxi Province, China
- Basic and Translational Research Laboratory of Immune Related Diseases, Xi'an, Shaanxi Province, China
| | - Baojun Zhang
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi'an Jiaotong University, Xi'an, Shaanxi Province, China
- Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi Province, China
- Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Xi'an, Shaanxi Province, China
- Basic and Translational Research Laboratory of Immune Related Diseases, Xi'an, Shaanxi Province, China
| |
Collapse
|
2
|
Nuclear receptor: Structure and function. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2023; 196:209-227. [PMID: 36813359 DOI: 10.1016/bs.pmbts.2022.07.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Ligand-dependent transcription factors are nuclear receptors (NRs) that regulate various critical cellular processes such as reproduction, metabolism, development, etc. NRs are classified into (subgroup 0 to subgroup 6) seven superfamilies based on ligand-binding characteristics. All NRs share a general domain structure (A/B, C, D, and E) with distinct essential functions. NRs as monomers, homodimers, or heterodimers bind to consensus DNA sequences known as Hormone Response Elements (HREs). Furthermore, nuclear receptor-binding efficiency depends on minor differences in the sequences of HREs, spacing between the two half-sites, and the flanking sequence of the response elements. NRs can trans-activate and repress their target genes. In positively regulated genes, ligand-bound NRs recruit coactivators to activate the target gene expression, and unliganded NRs cause transcriptional repression. On the other hand, NRs repress gene expression by different mechanisms: (i) ligand-dependent transcriptional repression, (ii) ligand-independent transcriptional repression. This chapter will briefly explain NR superfamilies, their structures, molecular mechanism of action and their role in pathophysiological conditions, etc. That could enable the discovery of new receptors and their ligands and may elucidate their roles in various physiological processes. In addition, therapeutic agonists and antagonists would be developed to control the dysregulation of nuclear receptor signaling.
Collapse
|
3
|
Jiao A, Liu H, Ding R, Zheng H, Zhang C, Feng Z, Lei L, Wang X, Su Y, Yang X, Sun C, Zhang L, Bai L, Sun L, Zhang B. Med1 Controls Effector CD8+ T Cell Differentiation and Survival through C/EBPβ-Mediated Transcriptional Control of T-bet. THE JOURNAL OF IMMUNOLOGY 2022; 209:855-863. [DOI: 10.4049/jimmunol.2200037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Accepted: 06/25/2022] [Indexed: 01/04/2023]
Abstract
Abstract
Effector CD8+ T cells are crucial players in adaptive immunity for effective protection against invading pathogens. The regulatory mechanisms underlying CD8+ T cell effector differentiation are incompletely understood. In this study, we defined a critical role of mediator complex subunit 1 (Med1) in controlling effector CD8+ T cell differentiation and survival during acute bacterial infection. Mice with Med1-deficient CD8+ T cells exhibited significantly impaired expansion with evidently reduced killer cell lectin-like receptor G1+ terminally differentiated and Ly6c+ effector cell populations. Moreover, Med1 deficiency led to enhanced cell apoptosis and expression of multiple inhibitory receptors (programmed cell death 1, T cell Ig and mucin domain–containing-3, and T cell immunoreceptor with Ig and ITIM domains). RNA-sequencing analysis revealed that T-bet– and Zeb2-mediated transcriptional programs were impaired in Med1-deficient CD8+ T cells. Overexpression of T-bet could rescue the differentiation and survival of Med1-deficient CD8+ effector T cells. Mechanistically, the transcription factor C/EBPβ promoted T-bet expression through interacting with Med1 in effector T cells. Collectively, our findings revealed a novel role of Med1 in regulating effector CD8+ T cell differentiation and survival in response to bacterial infection.
Collapse
Affiliation(s)
- Anjun Jiao
- *Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi’an Jiaotong University, Xi’an, Shaanxi, China
- †Institute of Infection and Immunity, Translational Medicine Institute, Xi’an Jiaotong University, Xi’an, Shaanxi, China
- ‡Key Laboratory of Environment and Genes Related to Diseases, Xi’an Jiaotong University, Ministry of Education, Xi’an, Shaanxi, China
- §Xi’an Key Laboratory of Immune Related Diseases, Xi’an Jiaotong University, Xi’an, Shaanxi, China
| | - Haiyan Liu
- *Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi’an Jiaotong University, Xi’an, Shaanxi, China
- †Institute of Infection and Immunity, Translational Medicine Institute, Xi’an Jiaotong University, Xi’an, Shaanxi, China
| | - Renyi Ding
- *Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi’an Jiaotong University, Xi’an, Shaanxi, China
- †Institute of Infection and Immunity, Translational Medicine Institute, Xi’an Jiaotong University, Xi’an, Shaanxi, China
| | - Huiqiang Zheng
- *Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi’an Jiaotong University, Xi’an, Shaanxi, China
- †Institute of Infection and Immunity, Translational Medicine Institute, Xi’an Jiaotong University, Xi’an, Shaanxi, China
| | - Cangang Zhang
- *Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi’an Jiaotong University, Xi’an, Shaanxi, China
- †Institute of Infection and Immunity, Translational Medicine Institute, Xi’an Jiaotong University, Xi’an, Shaanxi, China
| | - Zhao Feng
- *Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi’an Jiaotong University, Xi’an, Shaanxi, China
- †Institute of Infection and Immunity, Translational Medicine Institute, Xi’an Jiaotong University, Xi’an, Shaanxi, China
| | - Lei Lei
- *Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi’an Jiaotong University, Xi’an, Shaanxi, China
- †Institute of Infection and Immunity, Translational Medicine Institute, Xi’an Jiaotong University, Xi’an, Shaanxi, China
- ‡Key Laboratory of Environment and Genes Related to Diseases, Xi’an Jiaotong University, Ministry of Education, Xi’an, Shaanxi, China
- §Xi’an Key Laboratory of Immune Related Diseases, Xi’an Jiaotong University, Xi’an, Shaanxi, China
| | - Xin Wang
- *Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi’an Jiaotong University, Xi’an, Shaanxi, China
- †Institute of Infection and Immunity, Translational Medicine Institute, Xi’an Jiaotong University, Xi’an, Shaanxi, China
- ‡Key Laboratory of Environment and Genes Related to Diseases, Xi’an Jiaotong University, Ministry of Education, Xi’an, Shaanxi, China
- §Xi’an Key Laboratory of Immune Related Diseases, Xi’an Jiaotong University, Xi’an, Shaanxi, China
| | - Yanhong Su
- *Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi’an Jiaotong University, Xi’an, Shaanxi, China
- †Institute of Infection and Immunity, Translational Medicine Institute, Xi’an Jiaotong University, Xi’an, Shaanxi, China
| | - Xiaofeng Yang
- *Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi’an Jiaotong University, Xi’an, Shaanxi, China
- †Institute of Infection and Immunity, Translational Medicine Institute, Xi’an Jiaotong University, Xi’an, Shaanxi, China
- ‡Key Laboratory of Environment and Genes Related to Diseases, Xi’an Jiaotong University, Ministry of Education, Xi’an, Shaanxi, China
- §Xi’an Key Laboratory of Immune Related Diseases, Xi’an Jiaotong University, Xi’an, Shaanxi, China
| | - Chenming Sun
- *Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi’an Jiaotong University, Xi’an, Shaanxi, China
- †Institute of Infection and Immunity, Translational Medicine Institute, Xi’an Jiaotong University, Xi’an, Shaanxi, China
- ‡Key Laboratory of Environment and Genes Related to Diseases, Xi’an Jiaotong University, Ministry of Education, Xi’an, Shaanxi, China
- §Xi’an Key Laboratory of Immune Related Diseases, Xi’an Jiaotong University, Xi’an, Shaanxi, China
| | - Lianjun Zhang
- ¶Institute of Systems Medicine, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
- ‖Suzhou Institute of Systems Medicine, Suzhou, Jiangsu, China; and
| | - Liang Bai
- #Institute of Cardiovascular Science, Xi’an Jiaotong University Health Science Center, Xi’an, Shaanxi, China
| | - Lina Sun
- *Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi’an Jiaotong University, Xi’an, Shaanxi, China
- †Institute of Infection and Immunity, Translational Medicine Institute, Xi’an Jiaotong University, Xi’an, Shaanxi, China
- ‡Key Laboratory of Environment and Genes Related to Diseases, Xi’an Jiaotong University, Ministry of Education, Xi’an, Shaanxi, China
- §Xi’an Key Laboratory of Immune Related Diseases, Xi’an Jiaotong University, Xi’an, Shaanxi, China
| | - Baojun Zhang
- *Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi’an Jiaotong University, Xi’an, Shaanxi, China
- †Institute of Infection and Immunity, Translational Medicine Institute, Xi’an Jiaotong University, Xi’an, Shaanxi, China
- ‡Key Laboratory of Environment and Genes Related to Diseases, Xi’an Jiaotong University, Ministry of Education, Xi’an, Shaanxi, China
- §Xi’an Key Laboratory of Immune Related Diseases, Xi’an Jiaotong University, Xi’an, Shaanxi, China
| |
Collapse
|
4
|
Espina JEC, Bagamasbad PD. Synergistic gene regulation by thyroid hormone and glucocorticoid in the hippocampus. VITAMINS AND HORMONES 2021; 118:35-81. [PMID: 35180933 DOI: 10.1016/bs.vh.2021.11.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The hippocampus is considered the center for learning and memory in the brain, and its development and function is greatly affected by the thyroid and stress axes. Thyroid hormone (TH) and glucocorticoids (GC) are known to have a synergistic effect on developmental programs across several vertebrate species, and their effects on hippocampal structure and function are well-documented. However, there are few studies that focus on the processes and genes that are cooperatively regulated by the two hormone axes. Cross-regulation of the thyroid and stress axes in the hippocampus occurs on multiple levels such that TH can regulate the expression of the GC receptor (GR) while GC can modulate tissue sensitivity to TH by controlling the expression of TH receptor (TR) and enzymes involved in TH biosynthesis. Thyroid hormone and GC are also known to synergistically regulate the transcription of genes associated with neuronal function and development. Synergistic gene regulation by TH and GC may occur through the direct, cooperative action of TR and GR on common target genes, or by indirect mechanisms involving gene regulatory cascades activated by TR and GR. In this chapter, we describe the known physiological effects and underlying molecular mechanisms of TH and GC synergistic gene regulation in the hippocampus.
Collapse
Affiliation(s)
- Jose Ezekiel C Espina
- National Institute of Molecular Biology and Biotechnology, University of the Philippines Diliman, Quezon City, Philippines
| | - Pia D Bagamasbad
- National Institute of Molecular Biology and Biotechnology, University of the Philippines Diliman, Quezon City, Philippines.
| |
Collapse
|
5
|
Sakai Y, Ohba K, Sasaki S, Matsushita A, Nakamura HM, Kuroda G, Tsuriya D, Yamashita M, Suda T. Impairment of the Hypothalamus-Pituitary-Thyroid Axis Caused by Naturally Occurring GATA2 Mutations In Vitro. Int J Mol Sci 2021; 22:ijms221810015. [PMID: 34576178 PMCID: PMC8467656 DOI: 10.3390/ijms221810015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 09/11/2021] [Accepted: 09/13/2021] [Indexed: 12/31/2022] Open
Abstract
The transcription factor GATA2 regulates gene expression in several cells and tissues, including hematopoietic tissues and the central nervous system. Recent studies revealed that loss-of-function mutations in GATA2 are associated with hematological disorders. Our earlier in vitro studies showed that GATA2 plays an essential role in the hypothalamus–pituitary–thyroid axis (HPT axis) by regulating the genes encoding prepro-thyrotropin-releasing hormone (preproTRH) and thyroid-stimulating hormone β (TSHβ). However, the effect of GATA2 mutants on the transcriptional activity of their promoters remains unelucidated. In this study, we created five human GATA2 mutations (R308P, T354M, R396Q, R398W, and S447R) that were reported to be associated with hematological disorders and analyzed their functional properties, including transactivation potential and DNA-binding capacity toward the preproTRH and the TSHβ promoters. Three mutations (T354M, R396Q, and R398W) within the C-terminal zinc-finger domain reduced the basal GATA2 transcriptional activity on both the preproTRH and the TSHβ promoters with a significant loss of DNA binding affinity. Interestingly, only the R398W mutation reduced the GATA2 protein expression. Subsequent analysis demonstrated that the R398W mutation possibly facilitated the GATA2 degradation process. R308P and S447R mutants exhibited decreased transcriptional activity under protein kinase C compared to the wild-type protein. In conclusion, we demonstrated that naturally occurring GATA2 mutations impair the HPT axis through differential functional mechanisms in vitro.
Collapse
Affiliation(s)
- Yuki Sakai
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Shizuoka 431-3192, Japan; (Y.S.); (A.M.); (H.M.N.); (G.K.); (D.T.); (M.Y.); (T.S.)
| | - Kenji Ohba
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Shizuoka 431-3192, Japan; (Y.S.); (A.M.); (H.M.N.); (G.K.); (D.T.); (M.Y.); (T.S.)
- Medical Education Center, Hamamatsu University School of Medicine, Shizuoka 431-3192, Japan
- Correspondence: (K.O.); (S.S.); Tel.: +81-53-435-2263 (K.O. & S.S.); Fax: +81-53-435-2354 (K.O. & S.S.)
| | - Shigekazu Sasaki
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Shizuoka 431-3192, Japan; (Y.S.); (A.M.); (H.M.N.); (G.K.); (D.T.); (M.Y.); (T.S.)
- Correspondence: (K.O.); (S.S.); Tel.: +81-53-435-2263 (K.O. & S.S.); Fax: +81-53-435-2354 (K.O. & S.S.)
| | - Akio Matsushita
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Shizuoka 431-3192, Japan; (Y.S.); (A.M.); (H.M.N.); (G.K.); (D.T.); (M.Y.); (T.S.)
| | - Hiroko Misawa Nakamura
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Shizuoka 431-3192, Japan; (Y.S.); (A.M.); (H.M.N.); (G.K.); (D.T.); (M.Y.); (T.S.)
| | - Go Kuroda
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Shizuoka 431-3192, Japan; (Y.S.); (A.M.); (H.M.N.); (G.K.); (D.T.); (M.Y.); (T.S.)
| | - Daisuke Tsuriya
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Shizuoka 431-3192, Japan; (Y.S.); (A.M.); (H.M.N.); (G.K.); (D.T.); (M.Y.); (T.S.)
| | - Miho Yamashita
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Shizuoka 431-3192, Japan; (Y.S.); (A.M.); (H.M.N.); (G.K.); (D.T.); (M.Y.); (T.S.)
- International Center, Hamamatsu University School of Medicine, Shizuoka 431-3192, Japan
| | - Takafumi Suda
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Shizuoka 431-3192, Japan; (Y.S.); (A.M.); (H.M.N.); (G.K.); (D.T.); (M.Y.); (T.S.)
| |
Collapse
|
6
|
Ke S, Liu YY, Karthikraj R, Kannan K, Jiang J, Abe K, Milanesi A, Brent GA. Thyroid hormone receptor β sumoylation is required for thyrotropin regulation and thyroid hormone production. JCI Insight 2021; 6:e149425. [PMID: 34237030 PMCID: PMC8410017 DOI: 10.1172/jci.insight.149425] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 07/07/2021] [Indexed: 12/11/2022] Open
Abstract
Thyroid hormone receptor β (THRB) is posttranslationally modified by small ubiquitin-like modifier (SUMO). We generated a mouse model with a mutation that disrupted sumoylation at lysine 146 (K146Q) and resulted in desumoylated THRB as the predominant form in tissues. The THRB K146Q mutant mice had normal serum thyroxine (T4), markedly elevated serum thyrotropin-stimulating hormone (TSH; 81-fold above control), and enlargement of both the pituitary and the thyroid gland. The marked elevation in TSH, despite a normal serum T4, indicated blunted feedback regulation of TSH. The THRB K146Q mutation altered the recruitment of transcription factors to the TSHβ gene promoter, compared with WT, in hyperthyroidism and hypothyroidism. Thyroid hormone content (T4, T3, and rT3) in the thyroid gland of the THRB K146Q mice was 10-fold lower (per gram tissue) than control, despite normal TSH bioactivity. The expression of thyroglobulin and dual oxidase 2 genes in the thyroid was reduced and associated with modifications of cAMP response element-binding protein DNA binding and cofactor interactions in the presence of the desumoylated THRB. Therefore, thyroid hormone production had both TSH-dependent and TSH-independent components. We conclude that THRB sumoylation at K146 was required for normal TSH feedback regulation and TH synthesis in the thyroid gland, by a TSH-independent pathway.
Collapse
Affiliation(s)
- Sujie Ke
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, and Department of Physiology, David Geffen School of Medicine, UCLA and VA Greater Los Angeles Healthcare System, Los Angeles, California, USA.,Department of Endocrinology, Union Hospital, Fujian Medical University, Fuzhou, Fujian, China
| | - Yan-Yun Liu
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, and Department of Physiology, David Geffen School of Medicine, UCLA and VA Greater Los Angeles Healthcare System, Los Angeles, California, USA
| | | | - Kurunthachalam Kannan
- Department of Pediatrics and Department of Environmental Medicine, New York University School of Medicine, New York, New York, USA
| | - Jingjing Jiang
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, and Department of Physiology, David Geffen School of Medicine, UCLA and VA Greater Los Angeles Healthcare System, Los Angeles, California, USA.,Department of Endocrinology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Kiyomi Abe
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, and Department of Physiology, David Geffen School of Medicine, UCLA and VA Greater Los Angeles Healthcare System, Los Angeles, California, USA.,Department of Pediatrics, Keio University School of Medicine, Shinjuku-ku, Tokyo, Japan.,Tokyo Saiseikai Central Hospital, Minato-ku, Tokyo, Japan
| | - Anna Milanesi
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, and Department of Physiology, David Geffen School of Medicine, UCLA and VA Greater Los Angeles Healthcare System, Los Angeles, California, USA
| | - Gregory A Brent
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, and Department of Physiology, David Geffen School of Medicine, UCLA and VA Greater Los Angeles Healthcare System, Los Angeles, California, USA
| |
Collapse
|
7
|
Lei L, Yang X, Su Y, Zheng H, Liu J, Liu H, Zou Y, Jiao A, Wang X, Zhang C, Zhang X, Zhang J, Zhang D, Zhou X, Shi L, Liu E, Bai L, Sun C, Zhang B. Med1 controls CD8 T cell maintenance through IL-7R-mediated cell survival signalling. J Cell Mol Med 2021; 25:4870-4876. [PMID: 33733611 PMCID: PMC8107092 DOI: 10.1111/jcmm.16465] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 03/01/2021] [Accepted: 03/03/2021] [Indexed: 12/15/2022] Open
Abstract
Under steady‐state conditions, the pool size of peripheral CD8+ T cells is maintained through turnover and survival. Beyond TCR and IL‐7R signals, the underlying mechanisms are less well understood. In the present study, we found a significant reduction of CD8+ T cell proportion in spleens but not in thymi of mice with T cell‐specific deletion of Mediator Subunit 1 (Med1). A competitive transfer of wild‐type (WT) and Med1‐deficient CD8+ T cells reproduced the phenotype in the same recipients and confirmed intrinsic role of Med1. Furthermore, we observed a comparable degree of migration and proliferation but a significant increase of cell death in Med1‐deficient CD8+ T cells compared with WT counterparts. Finally, Med1‐deficient CD8+ T cells exhibited a decreased expression of interleukin‐7 receptor α (IL‐7Rα), down‐regulation of phosphorylated‐STAT5 (pSTAT5) and Bim up‐regulation. Collectively, our study reveals a novel role of Med1 in the maintenance of CD8+ T cells through IL‐7Rα/STAT5 pathway‐mediated cell survival.
Collapse
Affiliation(s)
- Lei Lei
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi'an Jiaotong University, Xi'an, China.,Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, China.,Key Laboratory of Environment and Genes Related to Diseases (Xi'an Jiaotong University), Ministry of Education, Xi'an, China.,Xi'an Key Laboratory of Immune Related Diseases, Xi'an, China
| | - Xiaofeng Yang
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi'an Jiaotong University, Xi'an, China.,Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, China.,Key Laboratory of Environment and Genes Related to Diseases (Xi'an Jiaotong University), Ministry of Education, Xi'an, China.,Xi'an Key Laboratory of Immune Related Diseases, Xi'an, China
| | - Yanhong Su
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi'an Jiaotong University, Xi'an, China.,Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Huiqiang Zheng
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi'an Jiaotong University, Xi'an, China.,Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Jun Liu
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi'an Jiaotong University, Xi'an, China.,Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Haiyan Liu
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi'an Jiaotong University, Xi'an, China.,Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Yujing Zou
- Duke University Medical Center, Durham, NC, USA
| | - Anjun Jiao
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi'an Jiaotong University, Xi'an, China.,Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Xin Wang
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi'an Jiaotong University, Xi'an, China.,Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Cangang Zhang
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi'an Jiaotong University, Xi'an, China.,Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Xingzhe Zhang
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi'an Jiaotong University, Xi'an, China.,Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Jiahui Zhang
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi'an Jiaotong University, Xi'an, China.,Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Dan Zhang
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi'an Jiaotong University, Xi'an, China.,Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Xiaobo Zhou
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi'an Jiaotong University, Xi'an, China.,Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Lin Shi
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi'an Jiaotong University, Xi'an, China.,Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Enqi Liu
- Institute of Cardiovascular Science, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Liang Bai
- Institute of Cardiovascular Science, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Chenming Sun
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi'an Jiaotong University, Xi'an, China.,Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, China.,Key Laboratory of Environment and Genes Related to Diseases (Xi'an Jiaotong University), Ministry of Education, Xi'an, China.,Xi'an Key Laboratory of Immune Related Diseases, Xi'an, China
| | - Baojun Zhang
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi'an Jiaotong University, Xi'an, China.,Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, China.,Key Laboratory of Environment and Genes Related to Diseases (Xi'an Jiaotong University), Ministry of Education, Xi'an, China.,Xi'an Key Laboratory of Immune Related Diseases, Xi'an, China
| |
Collapse
|
8
|
Kuroda G, Sasaki S, Matsushita A, Ohba K, Sakai Y, Shinkai S, Nakamura HM, Yamagishi S, Sato K, Hirahara N, Oki Y, Ito M, Suzuki T, Suda T. G ATA2 mediates the negative regulation of the prepro-thyrotropin-releasing hormone gene by liganded T3 receptor β2 in the rat hypothalamic paraventricular nucleus. PLoS One 2020; 15:e0242380. [PMID: 33201916 PMCID: PMC7671546 DOI: 10.1371/journal.pone.0242380] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Accepted: 10/31/2020] [Indexed: 12/25/2022] Open
Abstract
Thyroid hormone (T3) inhibits thyrotropin-releasing hormone (TRH) synthesis in the hypothalamic paraventricular nucleus (PVN). Although the T3 receptor (TR) β2 is known to mediate the negative regulation of the prepro-TRH gene, its molecular mechanism remains unknown. Our previous studies on the T3-dependent negative regulation of the thyrotropin β subunit (TSHβ) gene suggest that there is a tethering mechanism, whereby liganded TRβ2 interferes with the function of the transcription factor, GATA2, a critical activator of the TSHβ gene. Interestingly, the transcription factors Sim1 and Arnt2, the determinants of PVN differentiation in the hypothalamus, are reported to induce expression of TRβ2 and GATA2 in cultured neuronal cells. Here, we confirmed the expression of the GATA2 protein in the TRH neuron of the rat PVN using immunohistochemistry with an anti-GATA2 antibody. According to an experimental study from transgenic mice, a region of the rat prepro-TRH promoter from nt. -547 to nt. +84 was able to mediate its expression in the PVN. We constructed a chloramphenicol acetyltransferase (CAT) reporter gene containing this promoter sequence (rTRH(547)-CAT) and showed that GATA2 activated the promoter in monkey kidney-derived CV1 cells. Deletion and mutation analyses identified a functional GATA-responsive element (GATA-RE) between nt. -357 and nt. -352. When TRβ2 was co-expressed, T3 reduced GATA2-dependent promoter activity to approximately 30%. Unexpectedly, T3-dependent negative regulation was maintained after mutation of the reported negative T3-responsive element, site 4. T3 also inhibited the GATA2-dependent transcription enhanced by cAMP agonist, 8-bromo-cAMP. A rat thyroid medullary carcinoma cell line, CA77, is known to express the preproTRH mRNA. Using a chromatin immunoprecipitation assay with this cell line where GATA2 expression plasmid was transfected, we observed the recognition of the GATA-RE by GATA2. We also confirmed GATA2 binding using gel shift assay with the probe for the GATA-RE. In CA77 cells, the activity of rTRH(547)-CAT was potentiated by overexpression of GATA2, and it was inhibited in a T3-dependent manner. These results suggest that GATA2 transactivates the rat prepro-TRH gene and that liganded TRβ2 interferes with this activation via a tethering mechanism as in the case of the TSHβ gene.
Collapse
Affiliation(s)
- Go Kuroda
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Shigekazu Sasaki
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
- * E-mail:
| | - Akio Matsushita
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Kenji Ohba
- Medical Education Center, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Yuki Sakai
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Shinsuke Shinkai
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Hiroko Misawa Nakamura
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Satoru Yamagishi
- Department of Organ and Tissue Anatomy, Hamamatsu University School of Medicine, Hamamatsu, Hamamatsu, Shizuoka, Japan
| | - Kohji Sato
- Department of Organ and Tissue Anatomy, Hamamatsu University School of Medicine, Hamamatsu, Hamamatsu, Shizuoka, Japan
| | - Naoko Hirahara
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Japanese Red Cross Shizuoka Hospital, Shizuoka, Shizuoka, Japan
| | - Yutaka Oki
- Department of Internal medicine, Hamamatsu Kita Hospital, Hamamatsu, Shizuoka, Japan
| | - Masahiko Ito
- Department of Virology and Parasitology, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Tetsuro Suzuki
- Department of Virology and Parasitology, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Takafumi Suda
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| |
Collapse
|
9
|
Hirahara N, Nakamura HM, Sasaki S, Matsushita A, Ohba K, Kuroda G, Sakai Y, Shinkai S, Haeno H, Nishio T, Yoshida S, Oki Y, Suda T. Liganded T3 receptor β2 inhibits the positive feedback autoregulation of the gene for GATA2, a transcription factor critical for thyrotropin production. PLoS One 2020; 15:e0227646. [PMID: 31940421 PMCID: PMC6961892 DOI: 10.1371/journal.pone.0227646] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Accepted: 12/23/2019] [Indexed: 12/26/2022] Open
Abstract
The serum concentration of thyrotropin (thyroid stimulating hormone, TSH) is drastically reduced by small increase in the levels of thyroid hormones (T3 and its prohormone, T4); however, the mechanism underlying this relationship is unknown. TSH consists of the chorionic gonadotropin α (CGA) and the β chain (TSHβ). The expression of both peptides is induced by the transcription factor GATA2, a determinant of the thyrotroph and gonadotroph differentiation in the pituitary. We previously reported that the liganded T3 receptor (TR) inhibits transactivation activity of GATA2 via a tethering mechanism and proposed that this mechanism, but not binding of TR with a negative T3-responsive element, is the basis for the T3-dependent inhibition of the TSHβ and CGA genes. Multiple GATA-responsive elements (GATA-REs) also exist within the GATA2 gene itself and mediate the positive feedback autoregulation of this gene. To elucidate the effect of T3 on this non-linear regulation, we fused the GATA-REs at -3.9 kb or +9.5 kb of the GATA2 gene with the chloramphenicol acetyltransferase reporter gene harbored in its 1S-promoter. These constructs were co-transfected with the expression plasmids for GATA2 and the pituitary specific TR, TRβ2, into kidney-derived CV1 cells. We found that liganded TRβ2 represses the GATA2-induced transactivation of these reporter genes. Multi-dimensional input function theory revealed that liganded TRβ2 functions as a classical transcriptional repressor. Then, we investigated the effect of T3 on the endogenous expression of GATA2 protein and mRNA in the gonadotroph-derived LβT2 cells. In this cell line, T3 reduced GATA2 protein independently of the ubiquitin proteasome system. GATA2 mRNA was drastically suppressed by T3, the concentration of which corresponds to moderate hypothyroidism and euthyroidism. These results suggest that liganded TRβ2 inhibits the positive feedback autoregulation of the GATA2 gene; moreover this mechanism plays an important role in the potent reduction of TSH production by T3.
Collapse
Affiliation(s)
- Naoko Hirahara
- Division of Endocrinology and Metabolism, Department of Internal medicine, Japanese Red Cross Shizuoka Hospital, Shizuoka, Shizuoka, Japan
| | - Hiroko Misawa Nakamura
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Shigekazu Sasaki
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
- * E-mail:
| | - Akio Matsushita
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Kenji Ohba
- Medical Education Center, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Go Kuroda
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Yuki Sakai
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Shinsuke Shinkai
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Hiroshi Haeno
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo Kashiwa, Kashiwa, Chiba, Japan
| | - Takuhiro Nishio
- Department of Integrated Human Sciences, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Shuichi Yoshida
- Department of Integrated Human Sciences, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Yutaka Oki
- Department of Family and Community Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Takafumi Suda
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| |
Collapse
|
10
|
Bargi-Souza P, Goulart-Silva F, Nunes MT. Novel aspects of T 3 actions on GH and TSH synthesis and secretion: physiological implications. J Mol Endocrinol 2017; 59:R167-R178. [PMID: 28951438 DOI: 10.1530/jme-17-0068] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Accepted: 09/26/2017] [Indexed: 12/27/2022]
Abstract
Thyroid hormones (THs) classically regulate the gene expression by transcriptional mechanisms. In pituitary, the encoding genes for growth hormone (GH) and thyroid-stimulating hormone (TSH) are examples of genes regulated by triiodothyronine (T3) in a positive and negative way, respectively. Recent studies have shown a rapid adjustment of GH and TSH synthesis/secretion induced by T3 posttranscriptional actions. In somatotrophs, T3 promotes an increase in Gh mRNA content, poly(A) tail length and binding to the ribosome, associated with a rearrangement of actin cytoskeleton. In thyrotrophs, T3 reduces Tshb mRNA content, poly(A) tail length and its association with the ribosome. In parallel, it promotes a redistribution of TSH secretory granules to more distal regions of the cell periphery, indicating a rapid effect of T3 inhibition of TSH secretion. T3 was shown to affect the content of tubulin and the polymerization of actin and tubulin cytoskeletons in the whole anterior pituitary gland, and to increase intracellular alpha (CGA) content. This review summarizes genomic and non-genomic/posttranscriptional actions of TH on the regulation of several steps of GH and TSH synthesis and secretion. These distinct mechanisms induced by T3 can occur simultaneously, even though non-genomic effects are promptly elicited and precede the genomic actions, coexisting in a functional network within the cells.
Collapse
Affiliation(s)
| | | | - M T Nunes
- Department of Physiology and Biophysics of the Institute of Biomedical SciencesUniversity of São Paulo, São Paulo, SP, Brazil
| |
Collapse
|
11
|
Figliozzi RW, Chen F, Hsia SV. Reversing thyroid-hormone-mediated repression of a HSV-1 promoter via computationally guided mutagenesis. J Cell Sci 2017; 130:3740-3748. [PMID: 28916515 DOI: 10.1242/jcs.204222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Accepted: 09/12/2017] [Indexed: 11/20/2022] Open
Abstract
Thyroid hormones (THs) and their DNA-binding nuclear receptors (TRs) direct transcriptional regulation in diverse ways depending on the host cell environment and specific promoter characteristics of TH-sensitive genes. This study sought to elucidate the impact on transcriptional repression of nucleotide sequence or orientation within TR binding sites - the TH response elements (TREs) of TH-sensitive promoters - to better understand ligand-dependent transcriptional repression of wild-type promoters. Computational analysis of the HSV-1 thymidine kinase (TK) gene TRE bound by TR and retinoid X receptor (RXR) revealed a single TRE point mutation sufficient to reverse the TRE orientation. In vitro experiments showed that the TRE point mutation had distinct impacts on promoter activity, sufficient to reverse the TH-dependent negative regulation in neuroendocrine differentiated cells. This point mutation altered the promoter's regulatory mechanism by discrete changes in transcription factor TR occupancy and altered enrichment of the repressive chromatin modification of histone-3-lysine-9-trimethyl (H3K9Me3). Insights relating to this negative TRE (nTRE) mechanism aids our understanding of other nTREs and TRE mutations associated with TH and herpes diseases.
Collapse
Affiliation(s)
- Robert W Figliozzi
- Department of Pharmaceutical Sciences, School of Pharmacy and Health Professions, University of Maryland Eastern Shore, Princess Anne, MD 21853, USA.,Department of Natural Sciences, School of Agriculture and Natural Sciences, University of Maryland Eastern Shore, Princess Anne, MD 21853, USA
| | - Feng Chen
- Department of Pharmaceutical Sciences, School of Pharmacy and Health Professions, University of Maryland Eastern Shore, Princess Anne, MD 21853, USA
| | - Shaochung V Hsia
- Department of Pharmaceutical Sciences, School of Pharmacy and Health Professions, University of Maryland Eastern Shore, Princess Anne, MD 21853, USA .,Department of Natural Sciences, School of Agriculture and Natural Sciences, University of Maryland Eastern Shore, Princess Anne, MD 21853, USA
| |
Collapse
|
12
|
Sasaki S, Matsushita A, Kuroda G, Nakamura HM, Oki Y, Suda T. The Mechanism of Negative Transcriptional Regulation by Thyroid Hormone: Lessons From the Thyrotropin β Subunit Gene. VITAMINS AND HORMONES 2017; 106:97-127. [PMID: 29407449 DOI: 10.1016/bs.vh.2017.06.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Thyroid hormone (T3) activates (positive regulation) or represses (negative regulation) target genes at the transcriptional level. The molecular mechanism of the former has been elucidated in detail; however, the mechanism for negative regulation has not been established. The best example of the gene that is negatively regulated by T3 is the thyrotropin (thyroid-stimulating hormone) β subunit (TSHβ) gene. Analogous to the T3-responsive element (TRE) in positive regulation, a negative TRE (nTRE) has been postulated in the TSHβ gene. However, TSHβ promoter analysis, performed in the presence of transcription factors Pit1 and GATA2, which are determinants of thyrotroph differentiation in the pituitary, revealed that the nTRE is dispensable for inhibition by T3. We propose a tethering model in which the T3 receptor is tethered to GATA2 via protein-protein interaction and inhibits GATA2-dependent transactivation of the TSHβ gene in a T3-dependent manner.
Collapse
Affiliation(s)
| | | | - Go Kuroda
- Hamamatsu University School of Medicine, Shizuoka, Japan
| | | | - Yutaka Oki
- Hamamatsu University School of Medicine, Shizuoka, Japan
| | - Takafumi Suda
- Hamamatsu University School of Medicine, Shizuoka, Japan
| |
Collapse
|
13
|
Schoenmakers N, Alatzoglou KS, Chatterjee VK, Dattani MT. Recent advances in central congenital hypothyroidism. J Endocrinol 2015; 227:R51-71. [PMID: 26416826 PMCID: PMC4629398 DOI: 10.1530/joe-15-0341] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Revised: 09/17/2015] [Accepted: 09/28/2015] [Indexed: 01/23/2023]
Abstract
Central congenital hypothyroidism (CCH) may occur in isolation, or more frequently in combination with additional pituitary hormone deficits with or without associated extrapituitary abnormalities. Although uncommon, it may be more prevalent than previously thought, affecting up to 1:16 000 neonates in the Netherlands. Since TSH is not elevated, CCH will evade diagnosis in primary, TSH-based, CH screening programs and delayed detection may result in neurodevelopmental delay due to untreated neonatal hypothyroidism. Alternatively, coexisting growth hormones or ACTH deficiency may pose additional risks, such as life threatening hypoglycaemia. Genetic ascertainment is possible in a minority of cases and reveals mutations in genes controlling the TSH biosynthetic pathway (TSHB, TRHR, IGSF1) in isolated TSH deficiency, or early (HESX1, LHX3, LHX4, SOX3, OTX2) or late (PROP1, POU1F1) pituitary transcription factors in combined hormone deficits. Since TSH cannot be used as an indicator of euthyroidism, adequacy of treatment can be difficult to monitor due to a paucity of alternative biomarkers. This review will summarize the normal physiology of pituitary development and the hypothalamic-pituitary-thyroid axis, then describe known genetic causes of isolated central hypothyroidism and combined pituitary hormone deficits associated with TSH deficiency. Difficulties in diagnosis and management of these conditions will then be discussed.
Collapse
Affiliation(s)
- Nadia Schoenmakers
- University of Cambridge Metabolic Research LaboratoriesWellcome Trust-Medical Research Council Institute of Metabolic Science, Addenbrooke's Hospital, Level 4, PO Box 289, Hills Road, Cambridge CB2 0QQ, UKDevelopmental Endocrinology Research GroupSection of Genetics and Epigenetics in Health and Disease, Genetics and Genomic Medicine Programme, UCL Institute of Child Health, London, UK
| | - Kyriaki S Alatzoglou
- University of Cambridge Metabolic Research LaboratoriesWellcome Trust-Medical Research Council Institute of Metabolic Science, Addenbrooke's Hospital, Level 4, PO Box 289, Hills Road, Cambridge CB2 0QQ, UKDevelopmental Endocrinology Research GroupSection of Genetics and Epigenetics in Health and Disease, Genetics and Genomic Medicine Programme, UCL Institute of Child Health, London, UK
| | - V Krishna Chatterjee
- University of Cambridge Metabolic Research LaboratoriesWellcome Trust-Medical Research Council Institute of Metabolic Science, Addenbrooke's Hospital, Level 4, PO Box 289, Hills Road, Cambridge CB2 0QQ, UKDevelopmental Endocrinology Research GroupSection of Genetics and Epigenetics in Health and Disease, Genetics and Genomic Medicine Programme, UCL Institute of Child Health, London, UK
| | - Mehul T Dattani
- University of Cambridge Metabolic Research LaboratoriesWellcome Trust-Medical Research Council Institute of Metabolic Science, Addenbrooke's Hospital, Level 4, PO Box 289, Hills Road, Cambridge CB2 0QQ, UKDevelopmental Endocrinology Research GroupSection of Genetics and Epigenetics in Health and Disease, Genetics and Genomic Medicine Programme, UCL Institute of Child Health, London, UK
| |
Collapse
|
14
|
Matsunaga H, Sasaki S, Suzuki S, Matsushita A, Nakamura H, Nakamura HM, Hirahara N, Kuroda G, Iwaki H, Ohba K, Morita H, Oki Y, Suda T. Essential Role of GATA2 in the Negative Regulation of Type 2 Deiodinase Gene by Liganded Thyroid Hormone Receptor β2 in Thyrotroph. PLoS One 2015; 10:e0142400. [PMID: 26571013 PMCID: PMC4646574 DOI: 10.1371/journal.pone.0142400] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Accepted: 10/21/2015] [Indexed: 12/30/2022] Open
Abstract
The inhibition of thyrotropin (thyroid stimulating hormone; TSH) by thyroid hormone (T3) and its receptor (TR) is the central mechanism of the hypothalamus-pituitary-thyroid axis. Two transcription factors, GATA2 and Pit-1, determine thyrotroph differentiation and maintain the expression of the β subunit of TSH (TSHβ). We previously reported that T3-dependent repression of the TSHβ gene is mediated by GATA2 but not by the reported negative T3-responsive element (nTRE). In thyrotrophs, T3 also represses mRNA of the type-2 deiodinase (D2) gene, where no nTRE has been identified. Here, the human D2 promoter fused to the CAT or modified Renilla luciferase gene was co-transfected with Pit-1 and/or GATA2 expression plasmids into cell lines including CV1 and thyrotroph-derived TαT1. GATA2 but not Pit-1 activated the D2 promoter. Two GATA responsive elements (GATA-REs) were identified close to cAMP responsive element. The protein kinase A activator, forskolin, synergistically enhanced GATA2-dependent activity. Gel-shift and chromatin immunoprecipitation assays with TαT1 cells indicated that GATA2 binds to these GATA-REs. T3 repressed the GATA2-induced activity of the D2 promoter in the presence of the pituitary-specific TR, TRβ2. The inhibition by T3-bound TRβ2 was dominant over the synergism between GATA2 and forskolin. The D2 promoter is also stimulated by GATA4, the major GATA in cardiomyocytes, and this activity was repressed by T3 in the presence of TRα1. These data indicate that the GATA-induced activity of the D2 promoter is suppressed by T3-bound TRs via a tethering mechanism, as in the case of the TSHβ gene.
Collapse
Affiliation(s)
- Hideyuki Matsunaga
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, Shizuoka, 431–3192, Japan
| | - Shigekazu Sasaki
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, Shizuoka, 431–3192, Japan
| | - Shingo Suzuki
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, Shizuoka, 431–3192, Japan
| | - Akio Matsushita
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, Shizuoka, 431–3192, Japan
| | - Hirotoshi Nakamura
- Kuma Hospital, 8-2-35 Shimoyamate-dori, Chuo-ku, Kobe, Hyogo, 650–0011, Japan
| | - Hiroko Misawa Nakamura
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, Shizuoka, 431–3192, Japan
| | - Naoko Hirahara
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, Shizuoka, 431–3192, Japan
| | - Go Kuroda
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, Shizuoka, 431–3192, Japan
| | - Hiroyuki Iwaki
- Division of Endocrinology, Seirei Hamamatsu General Hospital, 2-12-12 Sumiyoshi, Naka-ku, Hamamatsu, Shizuoka, 430–0906, Japan
| | - Kenji Ohba
- Duke-NUS Graduate Medical School Singapore, No 8 College Road, Level 8th, 169857, Singapore
| | - Hiroshi Morita
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, Shizuoka, 431–3192, Japan
| | - Yutaka Oki
- Department of Family and Community Medicine, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, Shizuoka, 431–3192, Japan
| | - Takafumi Suda
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, Shizuoka, 431–3192, Japan
| |
Collapse
|
15
|
Iwaki H, Sasaki S, Matsushita A, Ohba K, Matsunaga H, Misawa H, Oki Y, Ishizuka K, Nakamura H, Suda T. Essential role of TEA domain transcription factors in the negative regulation of the MYH 7 gene by thyroid hormone and its receptors. PLoS One 2014; 9:e88610. [PMID: 24781449 PMCID: PMC4004540 DOI: 10.1371/journal.pone.0088610] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Accepted: 01/14/2014] [Indexed: 12/20/2022] Open
Abstract
MYH7 (also referred to as cardiac myosin heavy chain β) gene expression is known to be repressed by thyroid hormone (T3). However, the molecular mechanism by which T3 inhibits the transcription of its target genes (negative regulation) remains to be clarified, whereas those of transcriptional activation by T3 (positive regulation) have been elucidated in detail. Two MCAT (muscle C, A, and T) sites and an A/T-rich region in the MYH7 gene have been shown to play a critical role in the expression of this gene and are known to be recognized by the TEAD/TEF family of transcription factors (TEADs). Using a reconstitution system with CV-1 cells, which has been utilized in the analysis of positive as well as negative regulation, we demonstrate that both T3 receptor (TR) β1 and α1 inhibit TEAD-dependent activation of the MYH7 promoter in a T3 dose-dependent manner. TRβ1 bound with GC-1, a TRβ-selective T3 analog, also repressed TEAD-induced activity. Although T3-dependent inhibition required the DNA-binding domain (DBD) of TRβ1, it remained after the putative negative T3-responsive elements were mutated. A co-immunoprecipitation study demonstrated the in vivo association of TRβ1 with TEAD-1, and the interaction surfaces were mapped to the DBD of the TRβ1 and TEA domains of TEAD-1, both of which are highly conserved among TRs and TEADs, respectively. The importance of TEADs in MYH7 expression was also validated with RNA interference using rat embryonic cardiomyocyte H9c2 cells. These results indicate that T3-bound TRs interfere with transactivation by TEADs via protein-protein interactions, resulting in the negative regulation of MYH7 promoter activity.
Collapse
Affiliation(s)
- Hiroyuki Iwaki
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Shigekazu Sasaki
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
- * E-mail:
| | - Akio Matsushita
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Kenji Ohba
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Hideyuki Matsunaga
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Hiroko Misawa
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Yutaka Oki
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Keiko Ishizuka
- Department of Laboratory Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | | | - Takafumi Suda
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| |
Collapse
|
16
|
Yamamoto Y, Shiraishi M, Fujita M, Kojima I, Tanaka Y, Tachibana S. Triiodothyronine suppresses activin-induced differentiation of erythroleukemia K562 cells under hypoxic conditions. Mol Cell Biochem 2014; 391:217-24. [PMID: 24604674 DOI: 10.1007/s11010-014-2005-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2013] [Accepted: 02/21/2014] [Indexed: 12/13/2022]
Abstract
Thyroid hormone stimulates erythropoietic differentiation. However, severe anemia is sometimes seen in patients with hyperthyroidism, and the mechanisms have not been fully elucidated. Bone marrow is comprised about 2-8% oxygen, and the characteristics of hematopoietic stem cells have been shown to be influenced under hypoxia. Hypoxia-inducible factor-1 is a critical mediator of cellular responses to hypoxia and an important mediator in signal transduction of thyroid hormone [triiodothyronine (T3)]. The aim of this study was to investigate the effect of T3 on erythropoiesis under hypoxia mimicking physiological conditions in the bone marrow. We maintained human erythroleukemia K562 cells under hypoxic atmosphere (2% O₂) and examined their cellular characteristics. Compared to that under normal atmospheric conditions, cells under hypoxia showed a reduction in the proliferation rate and increase in the hemoglobin content or benzidine-positive rate, indicating promotion of erythroid differentiation. T3 had no effect on hypoxia-induced erythroid differentiation, but significantly inhibited activin A/erythroid differentiation factor-induced erythroid differentiation. Moreover, GATA2 mRNA expression was suppressed in association with erythroid differentiation, while T3 significantly diminished that suppression. These results suggest that T3 has a direct suppressive effect on erythroid differentiation under hypoxic conditions.
Collapse
Affiliation(s)
- Yoritsuna Yamamoto
- Division of Environmental Medicine, National Defense Medical College Research Institute, National Defense Medical College, 3-2 Namiki, Tokorozawa, Saitama, 359-8513, Japan,
| | | | | | | | | | | |
Collapse
|
17
|
Matsui K, Oda K, Mizuta S, Ishino R, Urahama N, Hasegawa N, Roeder RG, Ito M. Mediator subunit MED1 is a T3-dependent and T3-independent coactivator on the thyrotropin β gene promoter. Biochem Biophys Res Commun 2013; 440:184-9. [PMID: 24055033 DOI: 10.1016/j.bbrc.2013.09.061] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2013] [Accepted: 09/11/2013] [Indexed: 11/28/2022]
Abstract
The MED1 subunit of the Mediator transcriptional coregulator complex is a nuclear receptor-specific coactivator. A negative feedback mechanism of thyroid-stimulating hormone (TSH, or thyrotropin) expression in the thyrotroph in the presence of triiodothyronine (T3) is employed by liganded thyroid hormone receptor β (TRβ) on the TSHβ gene promoter, where conventional histone-modifying coactivators act as corepressors. We now provide evidence that MED1 is a ligand-dependent positive cofactor on this promoter. TSHβ gene transcription was attenuated in MED1 mutant mice in which the nuclear receptor-binding ability of MED1 was specifically disrupted. MED1 stimulated GATA2- and Pit1-mediated TSHβ gene promoter activity in a ligand-independent manner in cultured cells. MED1 also stimulated transcription from the TSHβ gene promoter in a T3-dependent manner. The transcription was further enhanced when the T3-dependent corepressors SRC1, SRC2, and HDAC2 were downregulated. Hence, MED1 is a T3-dependent and -independent coactivator on the TSHβ gene promoter.
Collapse
Affiliation(s)
- Keiji Matsui
- Laboratory of Hematology, Division of Medical Biophysics, Kobe University Graduate School of Health Sciences, 7-10-2 Tomogaoka, Suma-ku, Kobe 654-0142, Japan
| | | | | | | | | | | | | | | |
Collapse
|
18
|
Suter MA, Sangi-Haghpeykar H, Showalter L, Shope C, Hu M, Brown K, Williams S, Harris RA, Grove KL, Lane RH, Aagaard KM. Maternal high-fat diet modulates the fetal thyroid axis and thyroid gene expression in a nonhuman primate model. Mol Endocrinol 2012; 26:2071-80. [PMID: 23015752 DOI: 10.1210/me.2012-1214] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Thyroid hormone (TH) is an essential regulator of both fetal development and energy homeostasis. Although the association between subclinical hypothyroidism and obesity has been well studied, a causal relationship has yet to be established. Using our well-characterized nonhuman primate model of excess nutrition, we sought to investigate whether maternal high-fat diet (HFD)-induced changes in TH homeostasis may underlie later in life development of metabolic disorders and obesity. Here, we show that in utero exposure to a maternal HFD is associated with alterations of the fetal thyroid axis. At the beginning of the third trimester, fetal free T(4) levels are significantly decreased with HFD exposure compared with those of control diet-exposed offspring. Furthermore, transcription of the deiodinase, iodothyronine (DIO) genes, which help maintain thyroid homeostasis, are significantly (P < 0.05) disrupted in the fetal liver, thyroid, and hypothalamus. Genes involved in TH production are decreased (TRH, TSHR, TG, TPO, and SLC5A5) in hypothalamus and thyroid gland. In experiments designed to investigate the molecular underpinnings of these observations, we observe that the TH nuclear receptors and their downstream regulators are disrupted with maternal HFD exposure. In fetal liver, the expression of TH receptor β (THRB) is increased 1.9-fold (P = 0.012). Thorough analysis of the THRB promoter reveals a maternal diet-induced alteration in the fetal THRB histone code, alongside differential promoter occupancy of corepressors and coactivators. We speculate that maternal HFD exposure in utero may set the stage for later in life obesity through epigenomic modifications to the histone code, which modulates the fetal thyroid axis.
Collapse
Affiliation(s)
- Melissa A Suter
- Division of Maternal-Fetal Medicine, Baylor College of Medicine, Houston, TX 77030, USA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
19
|
Chiamolera MI, Sidhaye AR, Matsumoto S, He Q, Hashimoto K, Ortiga-Carvalho TM, Wondisford FE. Fundamentally distinct roles of thyroid hormone receptor isoforms in a thyrotroph cell line are due to differential DNA binding. Mol Endocrinol 2012; 26:926-39. [PMID: 22570333 DOI: 10.1210/me.2011-1290] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Thyroid hormones have a profound influence on human development and disease. The hypothalamic-pituitary-thyroid axis involves finely tuned feedback mechanisms to maintain thyroid hormone (TH) levels. Despite the important role of TH-negative feedback in regulating this axis, the mechanism by which this occurs is not clearly defined. Previous in vivo studies suggest separate roles for the two thyroid hormone receptor isoforms, THRA and THRB, in this axis. We performed studies using a unique pituitary thyrotroph cell line (TαT1.1) to determine the relative roles of THRA and THRB in the regulation of Tshb. Using chromatin immunoprecipitation assays, we found that THRB, not THRA, bound to the Tshb promoter. By selectively depleting THRB, THRA, or both THRA and THRB in TαT1.1 cells, we found that simultaneous knockdown of both THRB and THRA abolished T(3)-mediated down-regulation of Tshb at concentrations as high as 100 nm T(3). In contrast, THRA knockdown alone had no effect on T(3)-negative regulation, whereas THRB knockdown alone abolished T(3)-mediated down-regulation of Tshb mRNA levels at 10 nm but not 100 nm T(3) concentrations. Interestingly, chromatin immunoprecipitation assays showed that THRA becomes enriched on the Tshb promoter after knockdown of THRB. Thus, a likely mechanism for the differential effects of THR isoforms on Tshb may be based on their differential DNA-binding affinity to the promoter.
Collapse
|
20
|
The Mediator complex in thyroid hormone receptor action. Biochim Biophys Acta Gen Subj 2012; 1830:3867-75. [PMID: 22402254 DOI: 10.1016/j.bbagen.2012.02.012] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2011] [Revised: 02/16/2012] [Accepted: 02/21/2012] [Indexed: 10/28/2022]
Abstract
BACKGROUND Mediator is an evolutionarily conserved multisubunit complex that plays an essential regulatory role in eukaryotic transcription of protein-encoding genes. The human complex was first isolated as a transcriptional coactivator bound to the thyroid hormone receptor (TR) and has since been shown to play a key coregulatory role for a broad range of nuclear hormone receptors (NRs) as well as other signal-activated transcription factors. SCOPE OF REVIEW We provide a general overview of Mediator structure and function, summarize the mechanisms by which Mediator is targeted to NRs, and outline recent evidence revealing Mediator as a regulatory axis for other distinct coregulatory factors, chromatin modifying enzymes and cellular signal transduction pathways. MAJOR CONCLUSIONS Besides serving as a functional interface with the RNA polymerase II basal transcription machinery, Mediator plays a more versatile role in regulating transcription including the ability to: a) facilitate gene-specific chromatin looping events; b) coordinate chromatin modification events with preinitiation complex assembly; and c) regulate critical steps that occur during transcriptional elongation. The variably associated MED1 subunit continues to emerge as a pivotal player in Mediator function, not only as the primary interaction site for NRs, but also as a crucial interaction hub for other coregulatory factors, and as an important regulatory target for signal-activated kinases. GENERAL SIGNIFICANCE Mediator plays an integral coregulatory role at NR target genes by functionally interacting with the basal transcription apparatus and by coordinating the action of chromatin modifying enzymes and transcription elongation factors. This article is part of a Special Issue entitled Thyroid hormone signalling.
Collapse
|
21
|
Misawa H, Sasaki S, Matsushita A, Ohba K, Iwaki H, Matsunaga H, Suzuki S, Ishizuka K, Oki Y, Nakamura H. Liganded thyroid hormone receptor inhibits phorbol 12-O-tetradecanoate-13-acetate-induced enhancer activity via firefly luciferase cDNA. PLoS One 2012; 7:e28916. [PMID: 22253701 PMCID: PMC3258237 DOI: 10.1371/journal.pone.0028916] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2011] [Accepted: 11/17/2011] [Indexed: 11/27/2022] Open
Abstract
Thyroid hormone receptor (TR) belongs to the nuclear hormone receptor (NHR) superfamily and regulates the transcription of its target genes in a thyroid hormone (T3)-dependent manner. While the detail of transcriptional activation by T3 (positive regulation) has been clarified, the mechanism of T3-dependent repression (negative regulation) remains to be determined. In addition to naturally occurring negative regulations typically found for the thyrotropin β gene, T3-bound TR (T3/TR) is known to cause artificial negative regulation in reporter assays with cultured cells. For example, T3/TR inhibits the transcriptional activity of the reporter plasmids harboring AP-1 site derived from pUC/pBR322-related plasmid (pUC/AP-1). Artificial negative regulation has also been suggested in the reporter assay with firefly luciferase (FFL) gene. However, identification of the DNA sequence of the FFL gene using deletion analysis was not performed because negative regulation was evaluated by measuring the enzymatic activity of FFL protein. Thus, there remains the possibility that the inhibition by T3 is mediated via a DNA sequence other than FFL cDNA, for instance, pUC/AP-1 site in plasmid backbone. To investigate the function of FFL cDNA as a transcriptional regulatory sequence, we generated pBL-FFL-CAT5 by ligating FFL cDNA in the 5' upstream region to heterologous thymidine kinase promoter in pBL-CAT5, a chloramphenicol acetyl transferase (CAT)-based reporter gene, which lacks pUC/AP-1 site. In kidney-derived CV1 and choriocarcinoma-derived JEG3 cells, pBL-FFL-CAT5, but not pBL-CAT5, was strongly activated by a protein kinase C activator, phorbol 12-O-tetradecanoate-13-acetate (TPA). TPA-induced activity of pBL-FFL-CAT5 was negatively regulated by T3/TR. Mutation of nt. 626/640 in FFL cDNA attenuated the TPA-induced activation and concomitantly abolished the T3-dependent repression. Our data demonstrate that FFL cDNA sequence mediates the TPA-induced transcriptional activity, which is inhibited by T3/TR.
Collapse
Affiliation(s)
- Hiroko Misawa
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Shigekazu Sasaki
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
- * E-mail:
| | - Akio Matsushita
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Kenji Ohba
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Hiroyuki Iwaki
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Hideyuki Matsunaga
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Shingo Suzuki
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Keiko Ishizuka
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Yutaka Oki
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Hirotoshi Nakamura
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| |
Collapse
|
22
|
Chen W, Roeder RG. Mediator-dependent nuclear receptor function. Semin Cell Dev Biol 2011; 22:749-58. [PMID: 21854863 DOI: 10.1016/j.semcdb.2011.07.026] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2011] [Accepted: 07/20/2011] [Indexed: 12/24/2022]
Abstract
As gene-specific transcription factors, nuclear receptors are broadly involved in many important biological processes. Their function on target genes requires the stepwise assembly of different coactivator complexes that facilitate chromatin remodeling and subsequent preinitiation complex (PIC) formation and function. Mediator has proved to be a crucial, and general, nuclear receptor-interacting coactivator, with demonstrated functions in transcription steps ranging from chromatin remodeling to subsequent PIC formation and function. Here we discuss our current understanding of (i) pathways involved in Mediator recruitment and function through nuclear receptor target gene enhancers and promoters, (ii) conditional requirements for the strong nuclear receptor-Mediator interactions mediated by NR AF2 domains and the MED1 LXXLL motifs, (iii) Mediator functions, through different nuclear receptor-interacting subunits, in different metabolic pathways, (iv) emerging functions of Mediator as a corepressor in addition to its major role as a coactivator and (v) mechanisms by which Mediator acts to transmit signals from enhancer-bound nuclear receptors to the general transcription machinery at core promoters to effect PIC formation and function. As a nuclear receptor coregulator with increasingly diverse functions, Mediator may thus modulate nuclear receptor signaling through several different mechanisms.
Collapse
Affiliation(s)
- Wei Chen
- Laboratory of Biochemistry and Molecular Biology, The Rockefeller University, 1230 York Ave., New York, NY 10065, USA.
| | | |
Collapse
|
23
|
Ohba K, Sasaki S, Matsushita A, Iwaki H, Matsunaga H, Suzuki S, Ishizuka K, Misawa H, Oki Y, Nakamura H. GATA2 mediates thyrotropin-releasing hormone-induced transcriptional activation of the thyrotropin β gene. PLoS One 2011; 6:e18667. [PMID: 21533184 PMCID: PMC3077393 DOI: 10.1371/journal.pone.0018667] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2010] [Accepted: 03/08/2011] [Indexed: 11/19/2022] Open
Abstract
Thyrotropin-releasing hormone (TRH) activates not only the secretion of thyrotropin (TSH) but also the transcription of TSHβ and α-glycoprotein (αGSU) subunit genes. TSHβ expression is maintained by two transcription factors, Pit1 and GATA2, and is negatively regulated by thyroid hormone (T3). Our prior studies suggest that the main activator of the TSHβ gene is GATA2, not Pit1 or unliganded T3 receptor (TR). In previous studies on the mechanism of TRH-induced activation of the TSHβ gene, the involvements of Pit1 and TR have been investigated, but the role of GATA2 has not been clarified. Using kidney-derived CV1 cells and pituitary-derived GH3 and TαT1 cells, we demonstrate here that TRH signaling enhances GATA2-dependent activation of the TSHβ promoter and that TRH-induced activity is abolished by amino acid substitution in the GATA2-Zn finger domain or mutation of GATA-responsive element in the TSHβ gene. In CV1 cells transfected with TRH receptor expression plasmid, GATA2-dependent transactivation of αGSU and endothelin-1 promoters was enhanced by TRH. In the gel shift assay, TRH signal potentiated the DNA-binding capacity of GATA2. While inhibition by T3 is dominant over TRH-induced activation, unliganded TR or the putative negative T3-responsive element are not required for TRH-induced stimulation. Studies using GH3 cells showed that TRH-induced activity of the TSHβ promoter depends on protein kinase C but not the mitogen-activated protein kinase, suggesting that the signaling pathway is different from that in the prolactin gene. These results indicate that GATA2 is the principal mediator of the TRH signaling pathway in TSHβ expression.
Collapse
Affiliation(s)
- Kenji Ohba
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Shigekazu Sasaki
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
- * E-mail:
| | - Akio Matsushita
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Hiroyuki Iwaki
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Hideyuki Matsunaga
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Shingo Suzuki
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Keiko Ishizuka
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Hiroko Misawa
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Yutaka Oki
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Hirotoshi Nakamura
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| |
Collapse
|
24
|
Santos GM, Fairall L, Schwabe JW. Negative regulation by nuclear receptors: a plethora of mechanisms. Trends Endocrinol Metab 2011; 22:87-93. [PMID: 21196123 PMCID: PMC3053446 DOI: 10.1016/j.tem.2010.11.004] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2010] [Revised: 11/29/2010] [Accepted: 11/30/2010] [Indexed: 10/30/2022]
Abstract
Nuclear receptors are arguably the best understood transcriptional regulators. We know a great deal about the mechanisms through which they activate transcription in response to ligand binding and about the mechanisms through which they repress transcription in the absence of ligand. However, endocrine regulation often requires that ligand-bound receptors repress transcription of a subset of genes. An understanding of the mechanism for ligand-induced repression and how this differs from activation has proven elusive. A number of recent studies have directly or indirectly addressed this problem. Yet it seems the more evidence that accumulates, the more complex the mystery becomes.
Collapse
Affiliation(s)
| | - Louise Fairall
- Henry Wellcome Laboratories of Structural Biology, Department of Biochemistry, University of Leicester, Lancaster Road, Leicester, LE1 9HN, UK
| | - John W.R. Schwabe
- Henry Wellcome Laboratories of Structural Biology, Department of Biochemistry, University of Leicester, Lancaster Road, Leicester, LE1 9HN, UK
| |
Collapse
|
25
|
Figueira ACM, Polikarpov I, Veprintsev D, Santos GM. Dissecting the Relation between a nuclear receptor and GATA: binding affinity studies of thyroid hormone receptor and GATA2 on TSHβ promoter. PLoS One 2010; 5:e12628. [PMID: 20838640 PMCID: PMC2935386 DOI: 10.1371/journal.pone.0012628] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2010] [Accepted: 08/16/2010] [Indexed: 01/08/2023] Open
Abstract
Background Much is known about how genes regulated by nuclear receptors (NRs) are switched on in the presence of a ligand. However, the molecular mechanism for gene down-regulation by liganded NRs remains a conundrum. The interaction between two zinc-finger transcription factors, Nuclear Receptor and GATA, was described almost a decade ago as a strategy adopted by the cell to up- or down-regulate gene expression. More recently, cell-based assays have shown that the Zn-finger region of GATA2 (GATA2-Zf) has an important role in down-regulation of the thyrotropin gene (TSHβ) by liganded thyroid hormone receptor (TR). Methodology/Principal Findings In an effort to better understand the mechanism that drives TSHβ down-regulation by a liganded TR and GATA2, we have carried out equilibrium binding assays using fluorescence anisotropy to study the interaction of recombinant TR and GATA2-Zf with regulatory elements present in the TSHβ promoter. Surprisingly, we observed that ligand (T3) weakens TR binding to a negative regulatory element (NRE) present in the TSHβ promoter. We also show that TR may interact with GATA2-Zf in the absence of ligand, but T3 is crucial for increasing the affinity of this complex for different GATA response elements (GATA-REs). Importantly, these results indicate that TR complex formation enhances DNA binding of the TR-GATA2 in a ligand-dependent manner. Conclusions Our findings extend previous results obtained in vivo, further improving our understanding of how liganded nuclear receptors down-regulate gene transcription, with the cooperative binding of transcription factors to DNA forming the core of this process.
Collapse
Affiliation(s)
| | - Igor Polikarpov
- Instituto de Física de São Carlos, Universidade de São Paulo, São Carlos, São Paulo, Brazil
| | - Dmitry Veprintsev
- Biomolecular Research Laboratory, Paul Scherrer Institut, Villigen PSI, Switzerland
| | | |
Collapse
|
26
|
Kim KK, Park KS, Song SB, Kim KE. Insulin represses transcription of the thyroid stimulating hormone beta-subunit gene through increased recruitment of nuclear factor I. J Biol Chem 2010; 285:32003-11. [PMID: 20685655 DOI: 10.1074/jbc.m110.107573] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Although the regulation of thyroid stimulating hormone β-subunit gene (TSHβ) has been intensively studied, the functions of transcription factors involved are not fully understood. The authors found that the -615/-516 promoter region of the TSHβ interacts specifically with nuclear proteins derived from pituitary tissue or from cultured thyrotroph cells. The actual binding site at the nucleotide level, as revealed by DNase I protection assay, includes the consensus sequence for nuclear factor I (NFI). RT-PCR analysis indicated that NFI-B expression is restricted to thyrotroph cells in the anterior pituitary. EMSA and ChIP analysis showed that NFI-B binds most efficiently to the -588/-560 region of TSHβ promoter. The forced expressions of NFI-B markedly reduced TSHβ promoter activity and its mRNA expression. Furthermore, it was also shown that the -588/-560 region is involved in the insulin-mediated repression of the TSHβ. It was of particular interest to observe that NFI-B was recruited to the -588/-560 region of the TSHβ promoter in an insulin-dependent manner. Taken together, this study provides new insights of the delicate regulations of energy metabolism and hormonal homeostasis.
Collapse
Affiliation(s)
- Kee Kwang Kim
- Department of Biochemistry, College of Natural Sciences, Chungnam National University, Daejeon 305-764, Republic of Korea
| | | | | | | |
Collapse
|
27
|
Belakavadi M, Saunders J, Weisleder N, Raghava PS, Fondell JD. Repression of cardiac phospholamban gene expression is mediated by thyroid hormone receptor-{alpha}1 and involves targeted covalent histone modifications. Endocrinology 2010; 151:2946-56. [PMID: 20392835 PMCID: PMC2875831 DOI: 10.1210/en.2009-1241] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Phospholamban (PLB) is a critical regulator of Ca(2+) cycling in heart muscle cells, and its gene expression is markedly down-regulated by T(3). Nonetheless, little is known about the molecular mechanisms of T(3)-dependent gene silencing in cardiac muscle, and it remains unclear whether thyroid hormone receptors (TRs) directly bind at the PLB gene in vivo and facilitate transcriptional repression. To investigate the regulatory role of TRs in PLB transcription, we used a physiological murine heart muscle cell line (HL-1) that retains cardiac electrophysiological properties, expresses both TRalpha1 and TRbeta1 subtypes, and exhibits T(3)-dependent silencing of PLB expression. By performing RNA interference assays with HL-1 cells, we found that TRalpha1, but not TRbeta1, is essential for T(3)-dependent PLB gene repression. Interestingly, a PLB reporter gene containing only the core promoter sequences -156 to +64 displayed robust T(3)-dependent silencing in HL-1 cells, thus suggesting that transcriptional repression is facilitated by TRalpha1 via the PLB core promoter, a regulatory region highly conserved in mammals. Consistent with this notion, chromatin immunoprecipitation and in vitro binding assays show that TRalpha1 directly binds at the PLB core promoter region. Furthermore, addition of T(3) triggered alterations in covalent histone modifications at the PLB promoter that are associated with gene silencing, namely a pronounced decrease in both histone H3 acetylation and histone H3 lysine 4 methylation. Taken together, our data reveal that T(3)-dependent repression of PLB in cardiac myocytes is directly facilitated by TRalpha1 and involves the hormone-dependent recruitment of histone-modifying enzymes associated with transcriptional silencing.
Collapse
Affiliation(s)
- Madesh Belakavadi
- Department of Physiology and Biophysics, Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey, Piscataway, New Jersey 08854, USA
| | | | | | | | | |
Collapse
|
28
|
Ragnarsdóttir B, Jönsson K, Urbano A, Grönberg-Hernandez J, Lutay N, Tammi M, Gustafsson M, Lundstedt AC, Leijonhufvud I, Karpman D, Wullt B, Truedsson L, Jodal U, Andersson B, Svanborg C. Toll-like receptor 4 promoter polymorphisms: common TLR4 variants may protect against severe urinary tract infection. PLoS One 2010; 5:e10734. [PMID: 20505764 PMCID: PMC2873976 DOI: 10.1371/journal.pone.0010734] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2010] [Accepted: 04/12/2010] [Indexed: 01/07/2023] Open
Abstract
Background Polymorphisms affecting Toll-like receptor (TLR) structure appear to be rare, as would be expected due to their essential coordinator role in innate immunity. Here, we assess variation in TLR4 expression, rather than structure, as a mechanism to diversify innate immune responses. Methodology/Principal Findings We sequenced the TLR4 promoter (4,3 kb) in Swedish blood donors. Since TLR4 plays a vital role in susceptibility to urinary tract infection (UTI), promoter sequences were obtained from children with mild or severe disease. We performed a case-control study of pediatric patients with asymptomatic bacteriuria (ABU) or those prone to recurrent acute pyelonephritis (APN). Promoter activity of the single SNPs or multiple allelic changes corresponding to the genotype patterns (GPs) was tested. We then conducted a replication study in an independent cohort of adult patients with a history of childhood APN. Last, in vivo effects of the different GPs were examined after therapeutic intravesical inoculation of 19 patients with Escherichia coli 83972. We identified in total eight TLR4 promoter sequence variants in the Swedish control population, forming 19 haplotypes and 29 genotype patterns, some with effects on promoter activity. Compared to symptomatic patients and healthy controls, ABU patients had fewer genotype patterns, and their promoter sequence variants reduced TLR4 expression in response to infection. The ABU associated GPs also reduced innate immune responses in patients who were subjected to therapeutic urinary E. coli tract inoculation. Conclusions The results suggest that genetic variation in the TLR4 promoter may be an essential, largely overlooked mechanism to influence TLR4 expression and UTI susceptibility.
Collapse
Affiliation(s)
- Bryndís Ragnarsdóttir
- Department of Microbiology, Immunology and Glycobiology, Institute of Laboratory Medicine Lund, Lund University, Lund, Sweden
| | - Klas Jönsson
- Singapore Immunology Network (SIgN), Biomedical Sciences Institutes, Agency for Science, Technology, and Research (A*STAR), Singapore, Singapore
| | - Alexander Urbano
- Singapore Immunology Network (SIgN), Biomedical Sciences Institutes, Agency for Science, Technology, and Research (A*STAR), Singapore, Singapore
| | - Jenny Grönberg-Hernandez
- Department of Urology, Institute for Clinical Sciences Lund, Lund University Hospital, Lund, Sweden
| | - Nataliya Lutay
- Department of Microbiology, Immunology and Glycobiology, Institute of Laboratory Medicine Lund, Lund University, Lund, Sweden
| | - Martti Tammi
- Department of Biological Sciences, National University of Singapore (NUS), Singapore, Singapore
| | - Mattias Gustafsson
- Department of Microbiology, Immunology and Glycobiology, Institute of Laboratory Medicine Lund, Lund University, Lund, Sweden
| | - Ann-Charlotte Lundstedt
- Department of Microbiology, Immunology and Glycobiology, Institute of Laboratory Medicine Lund, Lund University, Lund, Sweden
| | - Irene Leijonhufvud
- Department of Microbiology, Immunology and Glycobiology, Institute of Laboratory Medicine Lund, Lund University, Lund, Sweden
| | - Diana Karpman
- Department of Pediatrics, Institute of Clinical Sciences Lund, Lund University, Lund, Sweden
| | - Björn Wullt
- Department of Urology, Institute for Clinical Sciences Lund, Lund University Hospital, Lund, Sweden
| | - Lennart Truedsson
- Department of Microbiology, Immunology and Glycobiology, Institute of Laboratory Medicine Lund, Lund University, Lund, Sweden
| | - Ulf Jodal
- Department of Pediatrics, The Queen Silvia Children's Hospital, Gothenburg University, Gothenburg, Sweden
| | - Björn Andersson
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
| | - Catharina Svanborg
- Department of Microbiology, Immunology and Glycobiology, Institute of Laboratory Medicine Lund, Lund University, Lund, Sweden
- Singapore Immunology Network (SIgN), Biomedical Sciences Institutes, Agency for Science, Technology, and Research (A*STAR), Singapore, Singapore
- * E-mail:
| |
Collapse
|
29
|
Sugrue ML, Vella KR, Morales C, Lopez ME, Hollenberg AN. The thyrotropin-releasing hormone gene is regulated by thyroid hormone at the level of transcription in vivo. Endocrinology 2010; 151:793-801. [PMID: 20032051 PMCID: PMC2817611 DOI: 10.1210/en.2009-0976] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The expression of the TRH gene in the paraventricular nucleus (PVH) of the hypothalamus is required for the normal production of thyroid hormone (TH) in rodents and humans. In addition, the regulation of TRH mRNA expression by TH, specifically in the PVH, ensures tight control of the set point of the hypothalamic-pituitary-thyroid axis. Although many studies have assumed that the regulation of TRH expression by TH is at the level of transcription, there is little data available to demonstrate this. We used two in vivo model systems to show this. In the first model system, we developed an in situ hybridization (ISH) assay directed against TRH heteronuclear RNA to measure TRH transcription directly in vivo. We show that in the euthyroid state, TRH transcription is present both in the PVH and anterior/lateral hypothalamus. In the hypothyroid state, transcription is activated in the PVH only and can be shut off within 5 h by TH. In the second model system, we employed transgenic mice that express the Cre recombinase under the control of the genomic region containing the TRH gene. Remarkably, TH regulates Cre expression in these mice in the PVH only. Taken together, these data affirm that TH regulates TRH at the level of transcription in the PVH only and that genomic elements surrounding the TRH gene mediate its regulation by T(3). Thus, it should be possible to identify the elements within the TRH locus that mediate its regulation by T(3) using in vivo approaches.
Collapse
Affiliation(s)
- Michelle L Sugrue
- Division of Endocrinology, Metabolism, and Diabetes, Beth Israel Deaconess Medical Center, 330 Brookline Avenue, E/CLS-0738, Boston, Massachusetts 02215, USA
| | | | | | | | | |
Collapse
|
30
|
Chan IH, Privalsky ML. Thyroid hormone receptor mutants implicated in human hepatocellular carcinoma display an altered target gene repertoire. Oncogene 2009; 28:4162-74. [PMID: 19749797 PMCID: PMC2787677 DOI: 10.1038/onc.2009.265] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Thyroid hormone receptors (TRs) are hormone-regulated transcription factors that control multiple aspects of normal physiology and development. Mutations in TRs have been identified at high frequency in certain cancers, including human hepatocellular carcinomas (HCCs). The majority of HCC-TR mutants bear lesions within their DNA recognition domains, and we have hypothesized that these lesions change the mutant receptors' target gene repertoire in a way crucial to their function as oncoproteins. Using stable cell transformants and expression array analysis, we determined that mutant TRs isolated from two different HCCs do, as hypothesized, display a target gene repertoire distinct from that of their normal TR progenitors. Only a subset of genes regulated by wild-type TRs was regulated by the corresponding HCC-TR mutants. More surprisingly, the HCC-TR mutants also gained the ability to regulate additional target genes not recognized by the wild-type receptors, and were not simply restricted to repression, but could also activate a subset of their target genes. We conclude that the TR mutants isolated from HCC have sustained multiple alterations from their normal progenitors that include not only changes in their transcriptional outputs, but also changes in the genes they target; both are likely to contribute to neoplasia.
Collapse
Affiliation(s)
- I H Chan
- Department of Microbiology, College of Biological Sciences, University of California at Davis, Davis, CA 95616, USA
| | | |
Collapse
|
31
|
Mukherjee K, Brocchieri L, Bürglin TR. A comprehensive classification and evolutionary analysis of plant homeobox genes. Mol Biol Evol 2009; 26:2775-94. [PMID: 19734295 PMCID: PMC2775110 DOI: 10.1093/molbev/msp201] [Citation(s) in RCA: 272] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The full complement of homeobox transcription factor sequences, including genes and pseudogenes, was determined from the analysis of 10 complete genomes from flowering plants, moss, Selaginella, unicellular green algae, and red algae. Our exhaustive genome-wide searches resulted in the discovery in each class of a greater number of homeobox genes than previously reported. All homeobox genes can be unambiguously classified by sequence evolutionary analysis into 14 distinct classes also characterized by conserved intron–exon structure and by unique codomain architectures. We identified many new genes belonging to previously defined classes (HD-ZIP I to IV, BEL, KNOX, PLINC, WOX). Other newly identified genes allowed us to characterize PHD, DDT, NDX, and LD genes as members of four new evolutionary classes and to define two additional classes, which we named SAWADEE and PINTOX. Our comprehensive analysis allowed us to identify several newly characterized conserved motifs, including novel zinc finger motifs in SAWADEE and DDT. Members of the BEL and KNOX classes were found in Chlorobionta (green plants) and in Rhodophyta. We found representatives of the DDT, WOX, and PINTOX classes only in green plants, including unicellular green algae, moss, and vascular plants. All 14 homeobox gene classes were represented in flowering plants, Selaginella, and moss, suggesting that they had already differentiated in the last common ancestor of moss and vascular plants.
Collapse
Affiliation(s)
- Krishanu Mukherjee
- Genetics Institute, Department of Molecular Genetics and Microbiology, College of Medicine, University of Florida, USA.
| | | | | |
Collapse
|
32
|
Ndong JDLC, Jean D, Rousselet N, Frade R. Down-regulation of the expression of RB18A/MED1, a cofactor of transcription, triggers strong tumorigenic phenotype of human melanoma cells. Int J Cancer 2009; 124:2597-606. [PMID: 19243021 DOI: 10.1002/ijc.24253] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The RB18A/MED1 human gene, also named TRAP220, DRIP205 and PBP, encodes for a single 205 kDa component, which interacts with nuclear receptors and transcription factors. RB18A/MED1 chromosome localization on locus 17q12-q21.1 suggests its involvement in human cancers. We herein analyzed RB18A/MED1 expression in human melanoma cell lines. We found that RB18A/MED1 is either highly or weakly expressed in melanoma cells, depending on their respectively non or highly-tumorigenic phenotype. We therefore investigated the possible existence of a relationship between the RB18A/MED1 expression level and melanoma cell phenotype. For this purpose, we down-regulated RB18A/MED1 expression by transfecting melanoma cells with a RB18A/MED1 small interfering RNA (siRNA), specific to the 3'-untranslated region of native RB18A/MED1 RNA, already demonstrated to inhibit specifically RB18A/MED1 protein expression. A nonspecific (scrambled) siRNA was used as control. This RB18A/MED1 siRNA did not modify the expression of cathepsin L forms or lamin A/C, nor the secretion of procathepsin L and MMP2 in transfected cells. Analysis using a microarray membrane with 113 cancer-related genes, western blot and specific tests, demonstrated that RB18A/MED1 knockdown significantly inhibits tissue inhibitor of metalloproteinase-3 expression, and increases uPAR expression, two genes well known to be involved in melanoma cell invasion, through modifications of the tumor microenvironment. Indeed, RB18A/MED1 knockdown in melanoma cells in vitro increased their invasive properties, without modification of cell proliferation. Furthermore, RB18A/MED1 knockdown in vivo switched melanoma phenotype from non to strongly-tumorigenic in nude mice. Our data thus demonstrated for the first time that a decrease of RB18A/MED1 expression in human melanoma cells increases their tumorigenic phenotype.
Collapse
Affiliation(s)
- Jean de La Croix Ndong
- INSERM U.672, Immunochemistry of Cell Regulations and Viral Interactions, EVRY Cedex, France
| | | | | | | |
Collapse
|
33
|
Ray S, Dutta D, Rumi MAK, Kent LN, Soares MJ, Paul S. Context-dependent function of regulatory elements and a switch in chromatin occupancy between GATA3 and GATA2 regulate Gata2 transcription during trophoblast differentiation. J Biol Chem 2008; 284:4978-88. [PMID: 19106099 DOI: 10.1074/jbc.m807329200] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
GATA transcription factors are important regulators of tissue-specific gene expression during development. GATA2 and GATA3 have been implicated in the regulation of trophoblast-specific genes. However, the regulatory mechanisms of GATA2 expression in trophoblast cells are poorly understood. In this study, we demonstrate that Gata2 is transcriptionally induced during trophoblast giant cell-specific differentiation. Transcriptional induction is associated with displacement of GATA3-dependent nucleoprotein complexes by GATA2-dependent nucleoprotein complexes at two regulatory regions, the -3.9- and +9.5-kb regions, of the mouse Gata2 locus. Analyses with reporter genes showed that, in trophoblast cells, -3.9- and +9.5-kb regions function as transcriptional enhancers in GATA motif independent and dependent fashions, respectively. We also found that knockdown of GATA3 by RNA interference induces GATA2 in undifferentiated trophoblast cells. Interestingly, three other known GATA motif-dependent Gata2 regulatory elements, the -1.8-, -2.8-, and -77-kb regions, which are important to regulate Gata2 in hematopoietic cells are not occupied by GATA factors in trophoblast cells. These elements do not show any enhancer activity and also possess inaccessible chromatin structure in trophoblast cells indicating a context-dependent function. Our results indicate that GATA3 directly represses Gata2 in undifferentiated trophoblast cells, and a switch in chromatin occupancy between GATA3 and GATA2 (GATA3/GATA2 switch) induces transcription during trophoblast differentiation. We predict that this GATA3/GATA2 switch is an important mechanism for the transcriptional regulation of other trophoblast-specific genes.
Collapse
Affiliation(s)
- Soma Ray
- Institute of Maternal-Fetal Biology and the Division of Cancer & Developmental Biology, Department of Pathology and Laboratory Medicine, University of Kansas Medical Center, Kansas City, Kansas 66160, USA
| | | | | | | | | | | |
Collapse
|
34
|
Trimarchi JM, Harpavat S, Billings NA, Cepko CL. Thyroid hormone components are expressed in three sequential waves during development of the chick retina. BMC DEVELOPMENTAL BIOLOGY 2008; 8:101. [PMID: 18854032 PMCID: PMC2579430 DOI: 10.1186/1471-213x-8-101] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/30/2008] [Accepted: 10/14/2008] [Indexed: 11/21/2022]
Abstract
BACKGROUND Thyroid hormone (TH) is an important developmental regulator in many tissues, including the retina. TH is activated locally via deiodinase 2 (Dio2), and it is destroyed by deiodinase 3 (Dio3). The TH receptors, TRa and TRb, mediate TH activity through hormone and DNA binding, and interactions with transcription regulators. RESULTS In the current work, the expression of these TH components was examined in the chick retina over time. Three waves of expression were characterized and found to be correlated with critical developmental events. The first wave occurred as progenitor cells began to make photoreceptors, the second as some cell types adopted a more mature location and differentiation state, and the third as Müller glia were generated. The cell types expressing the components, as well as the kinetics of expression within the cell cycle, were defined. TRb expression initiated during G2 in progenitor cells, concomitant with NeuroD and Otx2, which are expressed in early photoreceptor cells. TRb was expressed in photoreceptor cells for several days and then was reduced in expression level, as the expression of Crx, a later photoreceptor gene, became more evident. Dio3 was expressed throughout the cell cycle in progenitor cells. TRa was in most, if not all, retinal cells. Dio2 appeared transiently in a ventral (high) to dorsal gradient, likely in a subset of photoreceptor cells. CONCLUSION Multiple TH components were expressed in dynamic patterns in cycling progenitor cells and photoreceptors cells across the developing chick retina. These dynamic patterns suggest that TH is playing several roles in retinal development, both within the cycling progenitor cells and possibly with respect to the timing of differentiation of photoreceptor cells.
Collapse
Affiliation(s)
- Jeffrey M Trimarchi
- Department of Genetics, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA 02115, USA
| | | | - Nathan A Billings
- Department of Genetics, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA 02115, USA
| | - Constance L Cepko
- Department of Genetics and Howard Hughes Medical Institute, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA 02115, USA
| |
Collapse
|
35
|
Weitzel JM. To bind or not to bind - how to down-regulate target genes by liganded thyroid hormone receptor? Thyroid Res 2008; 1:4. [PMID: 19014660 PMCID: PMC2583983 DOI: 10.1186/1756-6614-1-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2008] [Accepted: 10/11/2008] [Indexed: 01/16/2023] Open
Abstract
The terrain is well explored regarding genes whose gene expression is up-regulated upon binding of thyroid hormone (TH) to its nuclear receptor. This regulation mechanism has been intensively studied and is well understood. In contrast, a lot of white spots remain on the map when it comes to target genes whose expression is down-regulated upon binding of TH to the thyroid hormone receptor (TR). Since no consistent mechanism has been proposed to explain ligand-dependent down-regulation of target gene transcription several working hypotheses favour different molecular mechanisms. Some working theories suggest a direct binding of TR to regulatory elements of target genes. Others favour models that are independent of a direct DNA binding event. However recent data suggested that a direct binding of TR to DNA is dispensable for TH-dependent negative gene transcription.
Collapse
Affiliation(s)
- Joachim M Weitzel
- Institute of Experimental Endocrinology, Charité University Medicine Berlin, 13353 Berlin, Germany.
| |
Collapse
|
36
|
Kerr J, Wood W, Ridgway EC. Basic science and clinical research advances in the pituitary transcription factors: Pit-1 and Prop-1. Curr Opin Endocrinol Diabetes Obes 2008; 15:359-63. [PMID: 18594277 DOI: 10.1097/med.0b013e3283060a56] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE OF REVIEW The pituitary-specific transcription factors, Pit-1 (also called Pou1f1) and prophet of Pit-1 (Prop-1), are critical for normal pituitary development and function. The aim of the present review is to highlight the recent basic science and clinical research advances in these transcription factors, as they relate to signaling pathway interactions, gene regulation, and mutations in human diseases. RECENT FINDINGS A number of important basic research discoveries have been made in the area of the pituitary-specific transcription factors, Pit-1 and Prop-1. Among these findings include: the effects of the Pit-1 coactivators, GATA-2 and TRAP-220, on the transcriptional regulation of the TSHbeta gene and thyrotropin expression, characterization of a novel pituitary regulator of Pit-1 expression, Atbf1, elucidation of the roles of Wnt and Notch signaling on Prop-1-mediated specification of the Pit-1 cell lineage and gonadotropes, and the identification of regulatory regions of the Prop-1 gene. Advances in clinical research include: the identification of novel mutations in the human POU1F1 and PROP-1 genes, and screening guidelines for patients with combined pituitary hormone deficiencies and possible mutations in these transcription factors. SUMMARY Research into the complex interplay of signaling pathways and transcription factors that regulate the pituitary gland are important areas of developmental biology and normal physiology. Clinically, such research has important implications for human diseases by identifying inheritable transcription factor mutations that may cause pituitary hormonal deficiencies.
Collapse
Affiliation(s)
- Janice Kerr
- Department of Medicine, Division of Endocrinology, Metabolism and Diabetes, University of Colorado, Denver, Aurora, Colorado 80045, USA.
| | | | | |
Collapse
|
37
|
Hepatocyte nuclear factor 4alpha contributes to thyroid hormone homeostasis by cooperatively regulating the type 1 iodothyronine deiodinase gene with GATA4 and Kruppel-like transcription factor 9. Mol Cell Biol 2008; 28:3917-31. [PMID: 18426912 DOI: 10.1128/mcb.02154-07] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Type 1 iodothyronine deiodinase (Dio1), a selenoenzyme catalyzing the bioactivation of thyroid hormone, is highly expressed in the liver. Dio1 mRNA and enzyme activity levels are markedly reduced in the livers of hepatocyte nuclear factor 4alpha (HNF4alpha)-null mice, thus accounting for its liver-specific expression. Consistent with this deficiency, serum T4 and rT3 concentrations are elevated in these mice compared with those in HNF4alpha-floxed control littermates; however, serum T3 levels are unchanged. Promoter analysis of the mouse Dio1 gene demonstrated that HNF4alpha plays a key role in the transactivation of the mouse Dio1 gene. Deletion and substitution mutation analyses demonstrated that a proximal HNF4alpha site (direct repeat 1 [TGGACAAAGGTGC]; HNF4alpha-RE) is crucial for transactivation of the mouse Dio1 gene by HNF4alpha. Mouse Dio1 is also stimulated by thyroid hormone signaling, but a direct role for thyroid hormone receptor action has not been reported. We also showed that thyroid hormone-inducible Krüppel-like factor 9 (KLF9) stimulates the mouse Dio1 promoter very efficiently through two CACCC sequences that are located on either side of HNF4alpha-RE. Furthermore, KLF9 functions together with HNF4alpha and GATA4 to synergistically activate the mouse Dio1 promoter, suggesting that Dio1 is regulated by thyroid hormone in the mouse through an indirect mechanism requiring prior KLF9 induction. In addition, we showed that physical interactions between the C-terminal zinc finger domain (Cf) of GATA4 and activation function 2 of HNF4alpha and between the basic domain adjacent to Cf of GATA4 and a C-terminal domain of KLF9 are both required for this synergistic response. Taken together, these results suggest that HNF4alpha regulates thyroid hormone homeostasis through transcriptional regulation of the mouse Dio1 gene with GATA4 and KLF9.
Collapse
|
38
|
Kawahara M, Iwasaki Y, Sakaguchi K, Taguchi T, Nishiyama M, Nigawara T, Tsugita M, Kambayashi M, Suda T, Hashimoto K. Predominant role of 25OHD in the negative regulation of PTH expression: Clinical relevance for hypovitaminosis D. Life Sci 2008; 82:677-83. [DOI: 10.1016/j.lfs.2007.12.027] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2007] [Revised: 11/21/2007] [Accepted: 12/21/2007] [Indexed: 01/22/2023]
|