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Liu SS, Fang X, Wen X, Liu JS, Alip M, Sun T, Wang YY, Chen HW. How mesenchymal stem cells transform into adipocytes: Overview of the current understanding of adipogenic differentiation. World J Stem Cells 2024; 16:245-256. [PMID: 38577237 PMCID: PMC10989283 DOI: 10.4252/wjsc.v16.i3.245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 01/15/2024] [Accepted: 02/18/2024] [Indexed: 03/25/2024] Open
Abstract
Mesenchymal stem cells (MSCs) are stem/progenitor cells capable of self-renewal and differentiation into osteoblasts, chondrocytes and adipocytes. The transformation of multipotent MSCs to adipocytes mainly involves two subsequent steps from MSCs to preadipocytes and further preadipocytes into adipocytes, in which the process MSCs are precisely controlled to commit to the adipogenic lineage and then mature into adipocytes. Previous studies have shown that the master transcription factors C/enhancer-binding protein alpha and peroxisome proliferation activator receptor gamma play vital roles in adipogenesis. However, the mechanism underlying the adipogenic differentiation of MSCs is not fully understood. Here, the current knowledge of adipogenic differentiation in MSCs is reviewed, focusing on signaling pathways, noncoding RNAs and epigenetic effects on DNA methylation and acetylation during MSC differentiation. Finally, the relationship between maladipogenic differentiation and diseases is briefly discussed. We hope that this review can broaden and deepen our understanding of how MSCs turn into adipocytes.
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Affiliation(s)
- Shan-Shan Liu
- Department of Reumatology and Immunology, Nanjing Drum Tower Hospital, The Affiliated Hospital of Medical School, Nanjing University, Nanjing 210008, Jiangsu Province, China
| | - Xiang Fang
- Department of Emergency, Nanjing Drum Tower Hospital, The Affiliated Hospital of Medical School, Nanjing University, Nanjing 210008, Jiangsu Province, China
| | - Xin Wen
- Department of Reumatology and Immunology, Nanjing Drum Tower Hospital, The Affiliated Hospital of Medical School, Nanjing University, Nanjing 210008, Jiangsu Province, China
| | - Ji-Shan Liu
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, China
| | - Miribangvl Alip
- Department of Reumatology and Immunology, Nanjing Drum Tower Hospital, The Affiliated Hospital of Medical School, Nanjing University, Nanjing 210008, Jiangsu Province, China
| | - Tian Sun
- Department of Reumatology and Immunology, Nanjing Drum Tower Hospital, The Affiliated Hospital of Medical School, Nanjing University, Nanjing 210008, Jiangsu Province, China
| | - Yuan-Yuan Wang
- Anhui Key Laboratory of Infection and Immunity, Bengbu Medical College, Bengbu 233000, Anhui Province, China
| | - Hong-Wei Chen
- Department of Reumatology and Immunology, Nanjing Drum Tower Hospital, The Affiliated Hospital of Medical School, Nanjing University, Nanjing 210008, Jiangsu Province, China.
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2
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Wang X, Li N, Zheng M, Yu Y, Zhang S. Acetylation and deacetylation of histone in adipocyte differentiation and the potential significance in cancer. Transl Oncol 2024; 39:101815. [PMID: 37935080 PMCID: PMC10654249 DOI: 10.1016/j.tranon.2023.101815] [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: 07/28/2023] [Revised: 10/17/2023] [Accepted: 10/22/2023] [Indexed: 11/09/2023] Open
Abstract
Adipocytes are derived from pluripotent mesenchymal stem cells and can develop into several cell types including adipocytes, myocytes, chondrocytes, and osteocytes. Adipocyte differentiation is regulated by a variety of transcription factors and signaling pathways. Various epigenetic factors, particularly histone modifications, play key roles in adipocyte differentiation and have indispensable functions in altering chromatin conformation. Histone acetylases and deacetylases participate in the regulation of protein acetylation, mediate transcriptional and post-translational modifications, and directly acetylate or deacetylate various transcription factors and regulatory proteins. The adipocyte differentiation of stem cells plays a key role in various metabolic diseases. Cancer stem cells(CSCs) play an important function in cancer metastasis, recurrence, and drug resistance, and have the characteristics of stem cells. They are expressed in various cell lineages, including adipocytes. Recent studies have shown that cancer stem cells that undergo epithelial-mesenchymal transformation can undergo adipocytic differentiation, thereby reducing the degree of malignancy. This opens up new possibilities for cancer treatment. This review summarizes the regulation of acetylation during adipocyte differentiation, involving the functions of histone acetylating and deacetylating enzymes as well as non-histone acetylation modifications. Mechanistic studies on adipogenesis and acetylation during the differentiation of cancer cells into a benign cell phenotype may help identify new targets for cancer treatment.
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Affiliation(s)
- Xiaorui Wang
- Department of Pathology, Tianjin Union Medical Center, Nankai University, Tianjin 300121, China; Graduate School, Tianjin Medical University, Tianjin 300070, China
| | - Na Li
- Department of Pathology, Tianjin Union Medical Center, Nankai University, Tianjin 300121, China; Graduate School, Tianjin Medical University, Tianjin 300070, China
| | - Minying Zheng
- Department of Pathology, Tianjin Union Medical Center, Nankai University, Tianjin 300121, China
| | - Yongjun Yu
- Department of Pathology, Tianjin Union Medical Center, Nankai University, Tianjin 300121, China
| | - Shiwu Zhang
- Department of Pathology, Tianjin Union Medical Center, Nankai University, Tianjin 300121, China.
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Mameri A, Côté J. JAZF1: A metabolic actor subunit of the NuA4/TIP60 chromatin modifying complex. Front Cell Dev Biol 2023; 11:1134268. [PMID: 37091973 PMCID: PMC10119425 DOI: 10.3389/fcell.2023.1134268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Accepted: 03/29/2023] [Indexed: 04/25/2023] Open
Abstract
The multisubunit NuA4/TIP60 complex is a lysine acetyltransferase, chromatin modifying factor and gene co-activator involved in diverse biological processes. The past decade has seen a growing appreciation for its role as a metabolic effector and modulator. However, molecular insights are scarce and often contradictory, underscoring the need for further mechanistic investigation. A particularly exciting route emerged with the recent identification of a novel subunit, JAZF1, which has been extensively linked to metabolic homeostasis. This review summarizes the major findings implicating NuA4/TIP60 in metabolism, especially in light of JAZF1 as part of the complex.
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4
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Basak M, Das K, Mahata T, Sengar AS, Verma SK, Biswas S, Bhadra K, Stewart A, Maity B. RGS7-ATF3-Tip60 Complex Promotes Hepatic Steatosis and Fibrosis by Directly Inducing TNFα. Antioxid Redox Signal 2023; 38:137-159. [PMID: 35521658 DOI: 10.1089/ars.2021.0174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Aims: The pathophysiological mechanism(s) underlying non-alcoholic fatty liver disease (NAFLD) have yet to be fully delineated and only a single drug, peroxisome proliferator-activated receptor (PPAR) α/γ agonist saroglitazar, has been approved. Here, we sought to investigate the role of Regulator of G Protein Signaling 7 (RGS7) in hyperlipidemia-dependent hepatic dysfunction. Results: RGS7 is elevated in the livers of NAFLD patients, particularly those with severe hepatic damage, pronounced insulin resistance, and high inflammation. In the liver, RGS7 forms a unique complex with transcription factor ATF3 and histone acetyltransferase Tip60, which is implicated in NAFLD. The removal of domains is necessary for ATF3/Tip60 binding compromises RGS7-dependent reactive oxygen species generation and cell death. Hepatic RGS7 knockdown (KD) prevented ATF3/Tip60 induction, and it provided protection against fibrotic remodeling and inflammation in high-fat diet-fed mice translating to improvements in liver function. Hyperlipidemia-dependent oxidative stress and metabolic dysfunction were largely reversed in RGS7 KD mice. Interestingly, saroglitazar failed to prevent RGS7/ATF3 upregulation but it did partially restore Tip60 levels. RGS7 drives the release of particularly tumor necrosis factor α (TNFα) from isolated hepatocytes, stellate cells and its depletion reverses steatosis, oxidative stress by direct TNFα exposure. Conversely, RGS7 overexpression in the liver is sufficient to trigger oxidative stress in hepatocytes that can be mitigated via TNFα inhibition. Innovation: We discovered a novel non-canonical function for an R7RGS protein, which usually functions to regulate G protein coupled receptor (GPCR) signaling. This is the first demonstration for a functional role of RGS7 outside the retina and central nervous system. Conclusion: RGS7 represents a potential novel target for the amelioration of NAFLD. Antioxid. Redox Signal. 38, 137-159.
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Affiliation(s)
| | - Kiran Das
- Centre of Biomedical Research, Lucknow, India
| | | | | | | | - Sayan Biswas
- Department of Forensic Medicine, College of Medicine and Sagore Dutta Hospital, Kolkata, India
| | - Kakali Bhadra
- Department of Zoology, University of Kalyani, Kalyani, India
| | - Adele Stewart
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University, Jupiter, Florida, USA
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Janas JA, Zhang L, Luu JH, Demeter J, Meng L, Marro SG, Mall M, Mooney NA, Schaukowitch K, Ng YH, Yang N, Huang Y, Neumayer G, Gozani O, Elias JE, Jackson PK, Wernig M. Tip60-mediated H2A.Z acetylation promotes neuronal fate specification and bivalent gene activation. Mol Cell 2022; 82:4627-4646.e14. [PMID: 36417913 PMCID: PMC9779922 DOI: 10.1016/j.molcel.2022.11.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 08/28/2022] [Accepted: 10/31/2022] [Indexed: 11/23/2022]
Abstract
Cell lineage specification is accomplished by a concerted action of chromatin remodeling and tissue-specific transcription factors. However, the mechanisms that induce and maintain appropriate lineage-specific gene expression remain elusive. Here, we used an unbiased proteomics approach to characterize chromatin regulators that mediate the induction of neuronal cell fate. We found that Tip60 acetyltransferase is essential to establish neuronal cell identity partly via acetylation of the histone variant H2A.Z. Despite its tight correlation with gene expression and active chromatin, loss of H2A.Z acetylation had little effect on chromatin accessibility or transcription. Instead, loss of Tip60 and acetyl-H2A.Z interfered with H3K4me3 deposition and activation of a unique subset of silent, lineage-restricted genes characterized by a bivalent chromatin configuration at their promoters. Altogether, our results illuminate the mechanisms underlying bivalent chromatin activation and reveal that H2A.Z acetylation regulates neuronal fate specification by establishing epigenetic competence for bivalent gene activation and cell lineage transition.
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Affiliation(s)
- Justyna A Janas
- Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305, USA; Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Lichao Zhang
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Jacklyn H Luu
- Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305, USA; Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Janos Demeter
- Baxter Laboratory, Department of Microbiology & Immunology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Lingjun Meng
- Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305, USA; Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Samuele G Marro
- Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305, USA; Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Moritz Mall
- Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305, USA; Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Nancie A Mooney
- Baxter Laboratory, Department of Microbiology & Immunology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Katie Schaukowitch
- Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305, USA; Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Yi Han Ng
- Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305, USA; Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Nan Yang
- Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305, USA; Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Yuhao Huang
- Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305, USA; Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Gernot Neumayer
- Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305, USA; Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Or Gozani
- Department of Biology, Stanford University, Stanford, CA 94305, USA
| | - Joshua E Elias
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Peter K Jackson
- Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305, USA; Baxter Laboratory, Department of Microbiology & Immunology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Marius Wernig
- Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305, USA; Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA.
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Wang B, Chen D, Jiang R, Ntim M, Lu J, Xia M, Yang X, Wang Y, Kundu S, Guan R, Li S. TIP60 buffers acute stress response and depressive behaviour by controlling PPARγ-mediated transcription. Brain Behav Immun 2022; 101:410-422. [PMID: 35114329 DOI: 10.1016/j.bbi.2022.01.022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Revised: 12/29/2021] [Accepted: 01/25/2022] [Indexed: 12/23/2022] Open
Abstract
Tat-interacting protein 60 (TIP60) as nuclear receptors (NRs) coregulator, acts as a tumor suppressor and also has promising therapeutic potential to target Alzheimer's disease. Stress has been implicated in many psychiatric disorders, and these disorders are characterized by impairments in cognitive function. Until now, there are no experimental data available on the regulatory effect of TIP60 in acute stress and depression. There is also no definitive explanation on which specific modulation of target gene expression is achieved by TIP60. Here, we identify TIP60 as a novel positive regulator in response to acute restraint stress (ARS) and a potentially effective target of antidepressants. Firstly, we discovered increased hippocampal TIP60 expressions in the ARS model. Furthermore, using the TIP60 inhibitor, MG149, we proved that TIP60 function correlates with behavioral and synaptic activation in the two-hour ARS. Secondly, the lentivirus vector (LV)-TIP60overexpression (OE) was injected into the hippocampus prior to the chronic restraint stress (CRS) experiments and it was found that over-expressed TIP60 compensates for TIP60 decrease and improves depression index in CRS. Thirdly, through the intervention of TIP60 expression in vitro, we established the genetic regulation of TIP60 on synaptic proteins, confirmed the TIP60 function as a specific coactivator for PPARγ and found that the PPARγ-mediated TIP60 function modulates transcriptional activation of synaptic proteins. Finally, the LV-TIP60OE and PPARγ antagonist, GW9662, were both administered in the CRS model and the data indicated that blocking PPARγ significantly weakened the protective effect of TIP60 against the CRS-induced depression. Conclusively, these findings together support TIP60 as a novel positive factor in response to acute stress and interacts with PPARγ to modulate the pathological mechanism of CRS-induced depression.
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Affiliation(s)
- Bin Wang
- Department of Physiology, College of Basic Medical Sciences, Liaoning Provincial Key Laboratory of Cerebral Diseases, National-Local Joint Engineering Research Center for Drug-Research and Development (R&D) of Neurodegenerative Diseases, Dalian Medical University, Dalian, Liaoning, China
| | - Defang Chen
- Department of Physiology, College of Basic Medical Sciences, Liaoning Provincial Key Laboratory of Cerebral Diseases, National-Local Joint Engineering Research Center for Drug-Research and Development (R&D) of Neurodegenerative Diseases, Dalian Medical University, Dalian, Liaoning, China
| | - Rong Jiang
- Department of Physiology, Binzhou Medical University, Yantai Campus, 346 Guanhai Road, Laishan District, Yantai, Shandong, China
| | - Michael Ntim
- Department of Physiology, School of Medicine and Dentistry, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Jincheng Lu
- Department of Physiology, College of Basic Medical Sciences, Liaoning Provincial Key Laboratory of Cerebral Diseases, National-Local Joint Engineering Research Center for Drug-Research and Development (R&D) of Neurodegenerative Diseases, Dalian Medical University, Dalian, Liaoning, China
| | - Min Xia
- Department of Physiology, College of Basic Medical Sciences, Liaoning Provincial Key Laboratory of Cerebral Diseases, National-Local Joint Engineering Research Center for Drug-Research and Development (R&D) of Neurodegenerative Diseases, Dalian Medical University, Dalian, Liaoning, China
| | - XueWei Yang
- Department of Physiology, College of Basic Medical Sciences, Liaoning Provincial Key Laboratory of Cerebral Diseases, National-Local Joint Engineering Research Center for Drug-Research and Development (R&D) of Neurodegenerative Diseases, Dalian Medical University, Dalian, Liaoning, China
| | - Ying Wang
- Department of Cardiology, Institute of Heart and Vessel Diseases of Dalian Medical University, the Second Affiliated Hospital of Dalian Medical University, Dalian, Liaoning, China
| | - Supratik Kundu
- Department of Physiology, College of Basic Medical Sciences, Liaoning Provincial Key Laboratory of Cerebral Diseases, National-Local Joint Engineering Research Center for Drug-Research and Development (R&D) of Neurodegenerative Diseases, Dalian Medical University, Dalian, Liaoning, China
| | - Rongxiao Guan
- Department of Cardiology, Institute of Heart and Vessel Diseases of Dalian Medical University, the Second Affiliated Hospital of Dalian Medical University, Dalian, Liaoning, China
| | - Shao Li
- Department of Physiology, College of Basic Medical Sciences, Liaoning Provincial Key Laboratory of Cerebral Diseases, National-Local Joint Engineering Research Center for Drug-Research and Development (R&D) of Neurodegenerative Diseases, Dalian Medical University, Dalian, Liaoning, China.
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7
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Dacic M, Shibu G, Rogatsky I. Physiological Convergence and Antagonism Between GR and PPARγ in Inflammation and Metabolism. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1390:123-141. [PMID: 36107316 DOI: 10.1007/978-3-031-11836-4_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Nuclear receptors (NRs) are transcription factors that modulate gene expression in a ligand-dependent manner. The ubiquitously expressed glucocorticoid receptor (GR) and peroxisome proliferator-activated receptor gamma (PPARγ) represent steroid (type I) and non-steroid (type II) classes of NRs, respectively. The diverse transcriptional and physiological outcomes of their activation are highly tissue-specific. For example, in subsets of immune cells, such as macrophages, the signaling of GR and PPARγ converges to elicit an anti-inflammatory phenotype; in contrast, in the adipose tissue, their signaling can lead to reciprocal metabolic outcomes. This review explores the cooperative and divergent outcomes of GR and PPARγ functions in different cell types and tissues, including immune cells, adipose tissue and the liver. Understanding the coordinated control of these NR pathways should advance studies in the field and potentially pave the way for developing new therapeutic approaches to exploit the GR:PPARγ crosstalk.
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Affiliation(s)
- Marija Dacic
- Hospital for Special Surgery Research Institute, The David Rosenzweig Genomics Center, New York, NY, USA
- Graduate Program in Physiology, Biophysics and Systems Biology, Weill Cornell Graduate School of Medical Sciences, New York, NY, USA
| | - Gayathri Shibu
- Hospital for Special Surgery Research Institute, The David Rosenzweig Genomics Center, New York, NY, USA
- Graduate Program in Immunology and Microbial Pathogenesis, Weill Cornell Graduate School of Medical Sciences, New York, NY, USA
| | - Inez Rogatsky
- Hospital for Special Surgery Research Institute, The David Rosenzweig Genomics Center, New York, NY, USA.
- Graduate Program in Immunology and Microbial Pathogenesis, Weill Cornell Graduate School of Medical Sciences, New York, NY, USA.
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Qian K, Yu D, Wang W, Jiang M, Yang R, Brown R, Gong DW. STK38 is a PPARγ-interacting protein promoting adipogenesis. Adipocyte 2021; 10:524-531. [PMID: 34670478 PMCID: PMC8726646 DOI: 10.1080/21623945.2021.1980257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Peroxisome proliferator-activated receptor-γ (PPARγ) is the master regulator of adipogenesis, but knowledge about how PPARγ is regulated at the protein level is very limited. We aimed to identify PPARγ-interacting proteins which modulate PPARγ’s protein levels and transactivating activities in human adipocytes. We expressed Flag-tagged PPARγ in human preadipocytes as bait to capture PPARγ-associated proteins, followed by mass spectroscopy and proteomics analysis, which identified serine/threonine kinase 38 (STK38) as a major PPARγ-associated protein. Protein pulldown studies confirmed this protein–protein interaction in transfected cells, and reporter assays demonstrated that STK38 enhanced PPARγ’s transactivating activities without requiring STK38’s kinase activity. In cell-based assays, STK38 increased PPARγ protein stability, extending PPARγ’s half-life from ~1.08 to 1.95 h. Notably, in human preadipocytes, the overexpression of STK38 enhanced adipogenesis, whereas knockdown impaired the process in a PPARγ-dependent manner. Thus, we discovered that STK38 is a novel PPARγ-cofactor promoting adipogenesis, likely through stabilization of PPARγ
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Affiliation(s)
- Kun Qian
- Department of Gastrointestinal Surgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- Division of Endocrinology, Diabetes and Nutrition, Department of Medicine, University of Maryland School of Medicine, Baltimore, USA
| | - Daozhan Yu
- Division of Endocrinology, Diabetes and Nutrition, Department of Medicine, University of Maryland School of Medicine, Baltimore, USA
| | - Weiming Wang
- Division of Endocrinology, Diabetes and Nutrition, Department of Medicine, University of Maryland School of Medicine, Baltimore, USA
| | - Mengqi Jiang
- Division of Endocrinology, Diabetes and Nutrition, Department of Medicine, University of Maryland School of Medicine, Baltimore, USA
- Department of Nutrition and Food Hygiene, School of Public Health, China Medical University, Shenyang, China
| | - Rongze Yang
- Division of Endocrinology, Diabetes and Nutrition, Department of Medicine, University of Maryland School of Medicine, Baltimore, USA
| | - Robert Brown
- Division of Endocrinology, Diabetes and Nutrition, Department of Medicine, University of Maryland School of Medicine, Baltimore, USA
| | - Da-Wei Gong
- Division of Endocrinology, Diabetes and Nutrition, Department of Medicine, University of Maryland School of Medicine, Baltimore, USA
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Simeon J, Thrush J, Bailey TA. Angiopoietin-like protein 4 is a chromatin-bound protein that enhances mammosphere formation in vitro and experimental triple-negative breast cancer brain and liver metastases in vivo. J Carcinog 2021; 20:8. [PMID: 34447288 PMCID: PMC8356708 DOI: 10.4103/jcar.jcar_20_20] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 09/30/2020] [Accepted: 01/06/2021] [Indexed: 11/18/2022] Open
Abstract
INTRODUCTION: Metastatic progression in triple-negative breast cancer (TNBC) patients occurs primarily because of nuclear reprogramming that includes chromatin remodeling and epigenetic modifications. The existing and most successful chemotherapies available for metastatic TNBC target nuclear proteins or damage DNA. The objectives here are to investigate an undescribed role for the molecular biology of nuclear angiopoietin-like protein 4 (ANGPTL4) and to characterize the effect of ectopic overexpression of ANGPTL4 in the metastatic biology of TNBC. MATERIALS AND METHODS: Lentiviral-mediated transduction was used to overexpress ANGPTL4 in the TNBC cell line MD Anderson–metastatic breast cancer 231. The overexpression of ANGPTL4 was confirmed by western blot and ELISA. Subcellular fractionation, western blot, and immunofluorescence microscopy were used to characterize the intracellular localization of ANGPTL4. Mammosphere culture and the anchorage-independent growth assay analyzed the metastatic potential of the cell line. Xenograft assays assessed the effect of ANGPTL4 overexpression on TNBC metastases in vivo. RESULTS: The ANGPTL4 overexpressing cell line formed larger mammospheres and anchorage-independent colonies in vitro and developed larger primary tumors, more liver metastases, and brain metastatic outgrowth in vivo in comparison to a cell line that expressed endogenous levels of ANGPTL4. ANGPTL4, aurora kinase A (AURKA), a mitotic kinase, and Tat-interacting protein p60 kDa (Tip60), a lysine acetyltransferase, associated with chromatin in the ANGPTL4 overexpressing cells but not in cells that expressed endogenous levels of ANGPTL4. CONCLUSIONS: The ANGPTL4 overexpressing cell line showed in vitro and in vivo activities that suggest that nuclear ANGPTL4, AURKA, and Tip60 may cooperatively modulate TNBC metastases within chromatin-remodeling complexes or DNA-associated machinery.
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Affiliation(s)
- Jodi Simeon
- Department of Biological Sciences, University of Arkansas, Fayetteville, Arkansas, USA.,Department of Cell and Molecular Biology Program, University of Arkansas, Fayetteville, Arkansas, USA
| | - Jessica Thrush
- Department of Biological Sciences, University of Arkansas, Fayetteville, Arkansas, USA.,Department of Honors College, University of Arkansas, Fayetteville, Arkansas, USA
| | - Tameka A Bailey
- Department of Biological Sciences, University of Arkansas, Fayetteville, Arkansas, USA.,Department of Cell and Molecular Biology Program, University of Arkansas, Fayetteville, Arkansas, USA
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Jugder BE, Kamareddine L, Watnick PI. Microbiota-derived acetate activates intestinal innate immunity via the Tip60 histone acetyltransferase complex. Immunity 2021; 54:1683-1697.e3. [PMID: 34107298 DOI: 10.1016/j.immuni.2021.05.017] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 04/05/2021] [Accepted: 05/24/2021] [Indexed: 02/06/2023]
Abstract
Microbe-derived acetate activates the Drosophila immunodeficiency (IMD) pathway in a subset of enteroendocrine cells (EECs) of the anterior midgut. In these cells, the IMD pathway co-regulates expression of antimicrobial and enteroendocrine peptides including tachykinin, a repressor of intestinal lipid synthesis. To determine whether acetate acts on a cell surface pattern recognition receptor or an intracellular target, we asked whether acetate import was essential for IMD signaling. Mutagenesis and RNA interference revealed that the putative monocarboxylic acid transporter Tarag was essential for enhancement of IMD signaling by dietary acetate. Interference with histone deacetylation in EECs augmented transcription of genes regulated by the steroid hormone ecdysone including IMD targets. Reduced expression of the histone acetyltransferase Tip60 decreased IMD signaling and blocked rescue by dietary acetate and other sources of intracellular acetyl-CoA. Thus, microbe-derived acetate induces chromatin remodeling within enteroendocrine cells, co-regulating host metabolism and intestinal innate immunity via a Tip60-steroid hormone axis that is conserved in mammals.
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Affiliation(s)
- Bat-Erdene Jugder
- Division of Infectious Diseases, Boston Children's Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA
| | - Layla Kamareddine
- Department of Biomedical Sciences, College of Health Sciences, QU Health, Qatar University, Doha, Qatar; Biomedical Research Center, Qatar University, Doha, Qatar; Biomedical and Pharmaceutical Research Unit, QU Health, Qatar University, Doha, Qatar
| | - Paula I Watnick
- Division of Infectious Diseases, Boston Children's Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA.
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Macchia PE, Nettore IC, Franchini F, Santana-Viera L, Ungaro P. Epigenetic regulation of adipogenesis by histone-modifying enzymes. Epigenomics 2021; 13:235-251. [PMID: 33502245 DOI: 10.2217/epi-2020-0304] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Many studies investigating the transcriptional control of adipogenesis have been published so far; recently the research is focusing on the role of epigenetic mechanisms in regulating the process of adipocyte development. Histone-modifying enzymes and the histone tails post-transcriptional modifications catalyzed by them, are fundamentally involved in the epigenetic regulation of adipogenesis. In our review, we will discuss recent advances in epigenomic regulation of adipogenesis with a focus on histone-modifying enzymes implicated in the various phases of adipocytes differentiation process from mesenchymal stem cells to mature adipocytes. Understanding adipogenesis, may provide new ways to treat obesity and related metabolic diseases.
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Affiliation(s)
- Paolo E Macchia
- Department of Clinical Medicine and Surgery, University of Naples Federico II, 80131 Napoli, Italy
| | - Immacolata C Nettore
- Department of Clinical Medicine and Surgery, University of Naples Federico II, 80131 Napoli, Italy
| | - Fabiana Franchini
- Department of Clinical Medicine and Surgery, University of Naples Federico II, 80131 Napoli, Italy
| | - Laura Santana-Viera
- National Research Council - Institute for Experimental Endocrinology & Oncology 'Gaetano Salvatore', 80145 Napoli, Italy
| | - Paola Ungaro
- National Research Council - Institute for Experimental Endocrinology & Oncology 'Gaetano Salvatore', 80145 Napoli, Italy
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12
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Nanduri R. Epigenetic Regulators of White Adipocyte Browning. EPIGENOMES 2021; 5:3. [PMID: 34968255 PMCID: PMC8594687 DOI: 10.3390/epigenomes5010003] [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: 11/01/2020] [Revised: 12/16/2020] [Accepted: 01/06/2021] [Indexed: 12/15/2022] Open
Abstract
Adipocytes play an essential role in maintaining energy homeostasis in mammals. The primary function of white adipose tissue (WAT) is to store energy; for brown adipose tissue (BAT), primary function is to release fats in the form of heat. Dysfunctional or excess WAT can induce metabolic disorders such as dyslipidemia, obesity, and diabetes. Preadipocytes or adipocytes from WAT possess sufficient plasticity as they can transdifferentiate into brown-like beige adipocytes. Studies in both humans and rodents showed that brown and beige adipocytes could improve metabolic health and protect from metabolic disorders. Brown fat requires activation via exposure to cold or β-adrenergic receptor (β-AR) agonists to protect from hypothermia. Considering the fact that the usage of β-AR agonists is still in question with their associated side effects, selective induction of WAT browning is therapeutically important instead of activating of BAT. Hence, a better understanding of the molecular mechanisms governing white adipocyte browning is vital. At the same time, it is also essential to understand the factors that define white adipocyte identity and inhibit white adipocyte browning. This literature review is a comprehensive and focused update on the epigenetic regulators crucial for differentiation and browning of white adipocytes.
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Affiliation(s)
- Ravikanth Nanduri
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
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13
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Gong S, Han X, Li M, Cai X, Liu W, Luo Y, Zhang SM, Zhou L, Ma Y, Huang X, Li Y, Zhou X, Zhu Y, Wang Q, Chen L, Ren Q, Zhang P, Ji L. Genetics and Clinical Characteristics of PPARγ Variant-Induced Diabetes in a Chinese Han Population. Front Endocrinol (Lausanne) 2021; 12:677130. [PMID: 34764936 PMCID: PMC8576343 DOI: 10.3389/fendo.2021.677130] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Accepted: 10/06/2021] [Indexed: 12/28/2022] Open
Abstract
OBJECTIVES PPARγ variants cause lipodystrophy, insulin resistance, and diabetes. This study aimed to determine the relationship between PPARγ genotypes and phenotypes and to explore the pathogenesis of diabetes beyond this relationship. METHODS PPARγ2 exons in 1,002 Chinese patients with early-onset type 2 diabetes (diagnosed before 40 years of age) were sequenced. The functions of variants were evaluated by in vitro assays. Additionally, a review of the literature was performed to obtain all reported cases with rare PPARγ2 variants to evaluate the characteristics of variants in different functional domains. RESULTS Six (0.6%) patients had PPARγ2 variant-induced diabetes (PPARG-DM) in the early-onset type 2 diabetes group, including three with the p.Tyr95Cys variant in activation function 1 domain (AF1), of which five patients (83%) had diabetic kidney disease (DKD). Functional experiments showed that p.Tyr95Cys suppresses 3T3-L1 preadipocyte differentiation. A total of 64 cases with damaging rare variants were reported previously. Patients with rare PPARγ2 variants in AF1 of PPARγ2 had a lower risk of lipodystrophy and a higher rate of obesity than those with variants in other domains, as confirmed in patients identified in this study. CONCLUSION The prevalence of PPARG-DM is similar in Caucasian and Chinese populations, and DKD was often observed in these patients. Patients with variants in the AF1 of PPARγ2 had milder clinical phenotypes and lack typical lipodystrophy features than those with variants in other domains. Our findings emphasize the importance of screening such patients via genetic testing and suggest that thiazolidinediones might be a good choice for these patients.
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Affiliation(s)
- Siqian Gong
- Department of Endocrinology and Metabolism, Peking University People’s Hospital, Peking University Diabetes Center, Beijing, China
| | - Xueyao Han
- Department of Endocrinology and Metabolism, Peking University People’s Hospital, Peking University Diabetes Center, Beijing, China
- *Correspondence: Linong Ji, ; Xueyao Han,
| | - Meng Li
- Department of Endocrinology and Metabolism, Peking University People’s Hospital, Peking University Diabetes Center, Beijing, China
| | - Xiaoling Cai
- Department of Endocrinology and Metabolism, Peking University People’s Hospital, Peking University Diabetes Center, Beijing, China
| | - Wei Liu
- Department of Endocrinology and Metabolism, Peking University People’s Hospital, Peking University Diabetes Center, Beijing, China
| | - Yingying Luo
- Department of Endocrinology and Metabolism, Peking University People’s Hospital, Peking University Diabetes Center, Beijing, China
| | - Si-min Zhang
- Department of Endocrinology and Metabolism, Peking University People’s Hospital, Peking University Diabetes Center, Beijing, China
| | - Lingli Zhou
- Department of Endocrinology and Metabolism, Peking University People’s Hospital, Peking University Diabetes Center, Beijing, China
| | - Yumin Ma
- Department of Endocrinology and Metabolism, Peking University People’s Hospital, Peking University Diabetes Center, Beijing, China
| | - Xiuting Huang
- Department of Endocrinology and Metabolism, Peking University People’s Hospital, Peking University Diabetes Center, Beijing, China
| | - Yufeng Li
- Department of Endocrinology, Beijing Pinggu District Hospital, Beijing, China
| | - Xianghai Zhou
- Department of Endocrinology and Metabolism, Peking University People’s Hospital, Peking University Diabetes Center, Beijing, China
| | - Yu Zhu
- Department of Endocrinology and Metabolism, Peking University People’s Hospital, Peking University Diabetes Center, Beijing, China
| | - Qiuping Wang
- Department of Endocrinology, Beijing Liangxiang Hospital, Beijing, China
| | - Ling Chen
- Department of Endocrinology and Metabolism, Peking University People’s Hospital, Peking University Diabetes Center, Beijing, China
| | - Qian Ren
- Department of Endocrinology and Metabolism, Peking University People’s Hospital, Peking University Diabetes Center, Beijing, China
| | - Ping Zhang
- Department of Endocrinology and Metabolism, Peking University People’s Hospital, Peking University Diabetes Center, Beijing, China
| | - Linong Ji
- Department of Endocrinology and Metabolism, Peking University People’s Hospital, Peking University Diabetes Center, Beijing, China
- *Correspondence: Linong Ji, ; Xueyao Han,
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14
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Chakraborty S, Sinha S, Sengupta A. Emerging trends in chromatin remodeler plasticity in mesenchymal stromal cell function. FASEB J 2020; 35:e21234. [PMID: 33337557 DOI: 10.1096/fj.202002232r] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 11/10/2020] [Accepted: 11/13/2020] [Indexed: 12/13/2022]
Abstract
Emerging evidences highlight importance of epigenetic regulation and their integration with transcriptional and cell signaling machinery in determining tissue resident adult pluripotent mesenchymal stem/stromal cell (MSC) activity, lineage commitment, and multicellular development. Histone modifying enzymes and large multi-subunit chromatin remodeling complexes and their cell type-specific plasticity remain the central defining features of gene regulation and establishment of tissue identity. Modulation of transcription factor expression gradient ex vivo and concomitant flexibility of higher order chromatin architecture in response to signaling cues are exciting approaches to regulate MSC activity and tissue rejuvenation. Being an important constituent of the adult bone marrow microenvironment/niche, pathophysiological perturbation in MSC homeostasis also causes impaired hematopoietic stem/progenitor cell function in a non-cell autonomous mechanism. In addition, pluripotent MSCs can function as immune regulatory cells, and they reside at the crossroad of innate and adaptive immune response pathways. Research in the past few years suggest that MSCs/stromal fibroblasts significantly contribute to the establishment of immunosuppressive microenvironment in shaping antitumor immunity. Therefore, it is important to understand mesenchymal stromal epigenome and transcriptional regulation to leverage its applications in regenerative medicine, epigenetic memory-guided trained immunity, immune-metabolic rewiring, and precision immune reprogramming. In this review, we highlight the latest developments and prospects in chromatin biology in determining MSC function in the context of lineage commitment and immunomodulation.
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Affiliation(s)
- Sayan Chakraborty
- Stem Cell & Leukemia Laboratory, Cancer Biology & Inflammatory Disorder Division, CSIR-Indian Institute of Chemical Biology, Kolkata, India.,Translational Research Unit of Excellence (TRUE), Kolkata, India
| | - Sayantani Sinha
- Stem Cell & Leukemia Laboratory, Cancer Biology & Inflammatory Disorder Division, CSIR-Indian Institute of Chemical Biology, Kolkata, India.,Translational Research Unit of Excellence (TRUE), Kolkata, India
| | - Amitava Sengupta
- Stem Cell & Leukemia Laboratory, Cancer Biology & Inflammatory Disorder Division, CSIR-Indian Institute of Chemical Biology, Kolkata, India.,Translational Research Unit of Excellence (TRUE), Kolkata, India
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15
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Peroxisome proliferator-activated receptor γ isoforms differentially regulate preadipocyte proliferation, apoptosis, and differentiation in chickens. Poult Sci 2020; 99:6410-6421. [PMID: 33248556 PMCID: PMC7705046 DOI: 10.1016/j.psj.2020.09.086] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 08/24/2020] [Accepted: 09/11/2020] [Indexed: 12/19/2022] Open
Abstract
Peroxisome proliferator-activated receptor γ (PPARγ) has 2 protein isoforms (PPARγ1 and PPARγ2) generated by alternative promoter usage and alternative splicing. However, their functional uniqueness and similarity remain unclear. In the study, we investigated the effects of lentivirus-mediated overexpression of PPARγ1 and PPARγ2 on proliferation, apoptosis, and differentiation of the immortalized chicken preadipocytes. Cell Counting Kit–8 assay showed PPARγ1 and PPARγ2 overexpression markedly suppressed cell proliferation, and fluorescence activated cell sorting analysis showed that PPARγ1 and PPARγ2 overexpression caused cell cycle arrest at G0/G1 phase. Cell death detection ELISA analysis showed both PPARγ1 and PPARγ2 overexpression induced cell apoptosis. Oil red O staining and gene expression analysis showed both PPARγ1 and PPARγ2 overexpression promoted preadipocyte differentiation. In the presence of PPARγ ligand, rosiglitazone, PPARγ2 overexpression was more potent in inducing apoptosis, promoting adipogenesis, and suppressing cell proliferation than PPARγ1 overexpression. We further explored the molecular basis for their functional differences. Reporter gene assay showed that under ligand conditions, PPARγ2 overexpression resulted in 1.68-fold increase in transcription activity compared with PPARγ1. Electrophoretic mobility shift assay showed both PPARγ1 and PPARγ2 could bind to PPAR response element (PPRE) as heterodimer with retinoid X receptor alpha, and by comparison, PPARγ2 had a higher affinity for PPRE than PPARγ1. Reporter gene assay showed expression PPARγ1 and PPARγ2 similarly induced fatty acid synthase and adipocyte fatty acid–binding protein promoter activity but differentially induced lipoprotein lipase and perilipin 1 promoter activities. Coimmunoprecipitation analysis showed that PPARγ1 and PPARγ2 interacted similarly with the coactivators, Tat-interacting protein 60. Taken together, our results demonstrate that PPARγ1 and PPARγ2 differentially regulate preadipocyte proliferation, apoptosis, and differentiation as a result of their distinct and overlapping molecular functions.
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16
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Concise Review: The Regulatory Mechanism of Lysine Acetylation in Mesenchymal Stem Cell Differentiation. Stem Cells Int 2020; 2020:7618506. [PMID: 32399051 PMCID: PMC7204305 DOI: 10.1155/2020/7618506] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2019] [Accepted: 01/02/2020] [Indexed: 12/30/2022] Open
Abstract
Nowadays, the use of MSCs has attracted considerable attention in the global science and technology field, with the self-renewal and multidirectional differentiation potential for diabetes, obesity treatment, bone repair, nerve repair, myocardial repair, and so on. Epigenetics plays an important role in the regulation of mesenchymal stem cell differentiation, which has become a research hotspot in the medical field. This review focuses on the role of lysine acetylation modification on the determination of MSC differentiation direction. During this progress, the recruitment of lysine acetyltransferases (KATs) and lysine deacetylases (KDACs) is the crux of transcriptional mechanisms in the dynamic regulation of key genes controlling MSC multidirectional differentiation.
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17
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Broekema MF, Hollman DAA, Koppen A, van den Ham HJ, Melchers D, Pijnenburg D, Ruijtenbeek R, van Mil SWC, Houtman R, Kalkhoven E. Profiling of 3696 Nuclear Receptor-Coregulator Interactions: A Resource for Biological and Clinical Discovery. Endocrinology 2018; 159:2397-2407. [PMID: 29718163 DOI: 10.1210/en.2018-00149] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Accepted: 04/24/2018] [Indexed: 12/13/2022]
Abstract
Nuclear receptors (NRs) are ligand-inducible transcription factors that play critical roles in metazoan development, reproduction, and physiology and therefore are implicated in a broad range of pathologies. The transcriptional activity of NRs critically depends on their interaction(s) with transcriptional coregulator proteins, including coactivators and corepressors. Short leucine-rich peptide motifs in these proteins (LxxLL in coactivators and LxxxIxxxL in corepressors) are essential and sufficient for NR binding. With 350 different coregulator proteins identified to date and with many coregulators containing multiple interaction motifs, an enormous combinatorial potential is present for selective NR-mediated gene regulation. However, NR-coregulator interactions have often been determined experimentally on a one-to-one basis across diverse experimental conditions. In addition, NR-coregulator interactions are difficult to predict because the molecular determinants that govern specificity are not well established. Therefore, many biologically and clinically relevant NR-coregulator interactions may remain to be discovered. Here, we present a comprehensive overview of 3696 NR-coregulator interactions by systematically characterizing the binding of 24 nuclear receptors with 154 coregulator peptides. We identified unique ligand-dependent NR-coregulator interaction profiles for each NR, confirming many well-established NR-coregulator interactions. Hierarchical clustering based on the NR-coregulator interaction profiles largely recapitulates the classification of NR subfamilies based on the primary amino acid sequences of the ligand-binding domains, indicating that amino acid sequence is an important, although not the only, molecular determinant in directing and fine-tuning NR-coregulator interactions. This NR-coregulator peptide interactome provides an open data resource for future biological and clinical discovery as well as NR-based drug design.
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Affiliation(s)
- Marjoleine F Broekema
- Molecular Cancer Research and Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, CG Utrecht, Netherlands
| | - Danielle A A Hollman
- Molecular Cancer Research and Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, CG Utrecht, Netherlands
| | - Arjen Koppen
- Molecular Cancer Research and Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, CG Utrecht, Netherlands
| | | | - Diana Melchers
- PamGene International B. V., BJ 's-Hertogenbosch, Netherlands
| | - Dirk Pijnenburg
- PamGene International B. V., BJ 's-Hertogenbosch, Netherlands
| | - Rob Ruijtenbeek
- PamGene International B. V., BJ 's-Hertogenbosch, Netherlands
| | - Saskia W C van Mil
- Molecular Cancer Research and Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, CG Utrecht, Netherlands
| | - René Houtman
- PamGene International B. V., BJ 's-Hertogenbosch, Netherlands
| | - Eric Kalkhoven
- Molecular Cancer Research and Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, CG Utrecht, Netherlands
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18
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Tip60-mediated lipin 1 acetylation and ER translocation determine triacylglycerol synthesis rate. Nat Commun 2018; 9:1916. [PMID: 29765047 PMCID: PMC5953937 DOI: 10.1038/s41467-018-04363-w] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2017] [Accepted: 04/25/2018] [Indexed: 12/15/2022] Open
Abstract
Obesity is characterized by excessive fatty acid conversion to triacylglycerols (TAGs) in adipose tissues. However, how signaling networks sense fatty acids and connect to the stimulation of lipid synthesis remains elusive. Here, we show that homozygous knock-in mice carrying a point mutation at the Ser86 phosphorylation site of acetyltransferase Tip60 (Tip60SA/SA) display remarkably reduced body fat mass, and Tip60SA/SA females fail to nurture pups to adulthood due to severely reduced milk TAGs. Mechanistically, fatty acids stimulate Tip60-dependent acetylation and endoplasmic reticulum translocation of phosphatidic acid phosphatase lipin 1 to generate diacylglycerol for TAG synthesis, which is repressed by deacetylase Sirt1. Inhibition of Tip60 activity strongly blocks fatty acid-induced TAG synthesis while Sirt1 suppression leads to increased adiposity. Genetic analysis of loss-of-function mutants in Saccharomyces cerevisiae reveals a requirement of ESA1, yeast ortholog of Tip60, in TAG accumulation. These findings uncover a conserved mechanism linking fatty acid sensing to fat synthesis. The acetyltransferase Tip60 mediates signaling pathways by acetylating non-histone proteins. Here the authors show that fatty acids induce Tip60–dependent acetylation of phosphatidic acid phosphatase lipin1 which, then, translocates to the ER and generates diacylglycerols for triglyceride synthesis.
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19
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Jaiswal B, Gupta A. Modulation of Nuclear Receptor Function by Chromatin Modifying Factor TIP60. Endocrinology 2018; 159:2199-2215. [PMID: 29420715 DOI: 10.1210/en.2017-03190] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 01/31/2018] [Indexed: 02/07/2023]
Abstract
Nuclear receptors (NRs) are transcription factors that bind to specific DNA sequences known as hormone response elements located upstream of their target genes. Transcriptional activity of NRs can be modulated by binding of the compatible ligand and transient interaction with cellular coregulators, functioning either as coactivators or as corepressors. Many coactivator proteins possess intrinsic histone acetyltransferase (HAT) activity that catalyzes the acetylation of specific lysine residues in histone tails and loosens the histone-DNA interaction, thereby facilitating access of transcriptional factors to the regulatory sequences of the DNA. Tat interactive protein 60 (TIP60), a member of the Mof-Ybf2-Sas2-TIP60 family of HAT protein, is a multifunctional coregulator that controls a number of physiological processes including apoptosis, DNA damage repair, and transcriptional regulation. Over the last two decades or so, TIP60 has been extensively studied for its role as NR coregulator, controlling various aspect of steroid receptor functions. The aim of this review is to summarize the findings on the role of TIP60 as a coregulator for different classes of NRs and its overall functional implications. We also discuss the latest studies linking TIP60 to NR-associated metabolic disorders and cancers for its potential use as a therapeutic drug target in future.
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Affiliation(s)
- Bharti Jaiswal
- Department of Life Sciences, Shiv Nadar University, Greater Noida, Uttar Pradesh, India
| | - Ashish Gupta
- Department of Life Sciences, Shiv Nadar University, Greater Noida, Uttar Pradesh, India
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Abstract
HIV infection and antiretroviral therapy (ART) treatment exert diverse effects on adipocytes and stromal-vascular fraction cells, leading to changes in adipose tissue quantity, distribution, and energy storage. A HIV-associated lipodystrophic condition was recognized early in the epidemic, characterized by clinically apparent changes in subcutaneous, visceral, and dorsocervical adipose depots. Underlying these changes is altered adipose tissue morphology and expression of genes central to adipocyte maturation, regulation, metabolism, and cytokine signaling. HIV viral proteins persist in circulation and locally within adipose tissue despite suppression of plasma viremia on ART, and exposure to these proteins impairs preadipocyte maturation and reduces adipocyte expression of peroxisome proliferator-activated receptor gamma (PPAR-γ) and other genes involved in cell regulation. Several early nucleoside reverse transcriptase inhibitor and protease inhibitor antiretroviral drugs demonstrated substantial adipocyte toxicity, including reduced mitochondrial DNA content and respiratory chain enzymes, reduced PPAR-γ and other regulatory gene expression, and increased proinflammatory cytokine production. Newer-generation agents, such as integrase inhibitors, appear to have fewer adverse effects. HIV infection also alters the balance of CD4+ and CD8+ T cells in adipose tissue, with effects on macrophage activation and local inflammation, while the presence of latently infected CD4+ T cells in adipose tissue may constitute a protected viral reservoir. This review provides a synthesis of the literature on how HIV virus, ART treatment, and host characteristics interact to affect adipose tissue distribution, immunology, and contribution to metabolic health, and adipocyte maturation, cellular regulation, and energy storage. © 2017 American Physiological Society. Compr Physiol 7:1339-1357, 2017.
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Affiliation(s)
- John R Koethe
- Division of Infectious Diseases, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
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21
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Judes G, Dubois L, Rifaï K, Daures M, Idrissou M, Bignon YJ, Penault-Llorca F, Bernard-Gallon D. TIP60 Histone Acetyltransferase in Adipose Tissue: Possible Linkages with Breast Cancer Development? OMICS-A JOURNAL OF INTEGRATIVE BIOLOGY 2017; 21:684-686. [PMID: 28873018 DOI: 10.1089/omi.2017.0117] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- Gaëlle Judes
- 1 Department of Oncogenetics, Centre Jean Perrin , CBRV, Clermont-Ferrand, France .,2 INSERM U 1240, IMOST, Clermont-Ferrand, France
| | - Lucas Dubois
- 1 Department of Oncogenetics, Centre Jean Perrin , CBRV, Clermont-Ferrand, France .,2 INSERM U 1240, IMOST, Clermont-Ferrand, France
| | - Khaldoun Rifaï
- 1 Department of Oncogenetics, Centre Jean Perrin , CBRV, Clermont-Ferrand, France .,2 INSERM U 1240, IMOST, Clermont-Ferrand, France
| | - Marine Daures
- 1 Department of Oncogenetics, Centre Jean Perrin , CBRV, Clermont-Ferrand, France .,2 INSERM U 1240, IMOST, Clermont-Ferrand, France
| | - Mouhamed Idrissou
- 1 Department of Oncogenetics, Centre Jean Perrin , CBRV, Clermont-Ferrand, France .,2 INSERM U 1240, IMOST, Clermont-Ferrand, France
| | - Yves-Jean Bignon
- 1 Department of Oncogenetics, Centre Jean Perrin , CBRV, Clermont-Ferrand, France .,2 INSERM U 1240, IMOST, Clermont-Ferrand, France
| | - Frédérique Penault-Llorca
- 2 INSERM U 1240, IMOST, Clermont-Ferrand, France .,3 Laboratory of Biopathology, Centre Jean Perrin , Clermont-Ferrand, France
| | - Dominique Bernard-Gallon
- 1 Department of Oncogenetics, Centre Jean Perrin , CBRV, Clermont-Ferrand, France .,2 INSERM U 1240, IMOST, Clermont-Ferrand, France
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22
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Bakshi K, Ranjitha B, Dubey S, Jagannadham J, Jaiswal B, Gupta A. Novel complex of HAT protein TIP60 and nuclear receptor PXR promotes cell migration and adhesion. Sci Rep 2017. [PMID: 28623334 PMCID: PMC5473911 DOI: 10.1038/s41598-017-03783-w] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
PXR is a member of nuclear receptor superfamily and a well-characterized mediator of xenobiotic metabolism. The classical mode of PXR activation involves its binding to appropriate ligand and subsequent heterodimerization with its partner RXR. However, various factors such as post-translational modifications and crosstalk with different cellular factors may also regulate the functional dynamics and behavior of PXR. In the present study, we have identified that TIP60, an essential lysine acetyltransferase protein interacts with unliganded PXR and together this complex promotes cell migration & adhesion. TIP60 utilizes its NR Box to interact with LBD region of PXR and acetylates PXR at lysine 170 to induce its intranuclear reorganization. Also, RXR is not required for TIP60-PXR complex formation and this complex does not induce ligand-dependent PXR target gene transactivation. Interestingly, we observed that PXR augments the catalytic activity of TIP60 for histones. This is the first report demonstrating the exclusive interaction of TIP60 with PXR and uncovers a potential role for the TIP60-PXR complex in cell migration and adhesion.
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Affiliation(s)
- Karishma Bakshi
- Department of Life Sciences, Shiv Nadar University, Greater Noida, India
| | - B Ranjitha
- Department of Life Sciences, Shiv Nadar University, Greater Noida, India
| | - Shraddha Dubey
- Department of Life Sciences, Shiv Nadar University, Greater Noida, India
| | - Jaisri Jagannadham
- Department of Life Sciences, Shiv Nadar University, Greater Noida, India
| | - Bharti Jaiswal
- Department of Life Sciences, Shiv Nadar University, Greater Noida, India
| | - Ashish Gupta
- Department of Life Sciences, Shiv Nadar University, Greater Noida, India.
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23
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Dijk W, Mattijssen F, de la Rosa Rodriguez M, Loza Valdes A, Loft A, Mandrup S, Kalkhoven E, Qi L, Borst JW, Kersten S. Hypoxia-Inducible Lipid Droplet-Associated Is Not a Direct Physiological Regulator of Lipolysis in Adipose Tissue. Endocrinology 2017; 158:1231-1251. [PMID: 28323980 PMCID: PMC5460841 DOI: 10.1210/en.2016-1809] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Accepted: 03/13/2017] [Indexed: 12/20/2022]
Abstract
Triglycerides are stored in specialized organelles called lipid droplets. Numerous proteins have been shown to be physically associated with lipid droplets and govern their function. Previously, the protein hypoxia-inducible lipid droplet-associated (HILPDA) was localized to lipid droplets and was suggested to inhibit triglyceride lipolysis in hepatocytes. We confirm the partial localization of HILPDA to lipid droplets and show that HILPDA is highly abundant in adipose tissue, where its expression is controlled by the peroxisome proliferator-activated receptor γ and by β-adrenergic stimulation. Levels of HILPDA markedly increased during 3T3-L1 adipocyte differentiation. Nevertheless, silencing of Hilpda using small interfering RNA or overexpression of Hilpda using adenovirus did not show a clear impact on 3T3-L1 adipogenesis. Following β-adrenergic stimulation, the silencing of Hilpda in adipocytes did not significantly alter the release of nonesterified fatty acids (NEFA) and glycerol. By contrast, adenoviral-mediated overexpression of Hilpda modestly attenuated the release of NEFA from adipocytes following β-adrenergic stimulation. In mice, adipocyte-specific inactivation of Hilpda had no effect on plasma levels of NEFA and glycerol after fasting, cold exposure, or pharmacological β-adrenergic stimulation. In addition, other relevant metabolic parameters were unchanged by adipocyte-specific inactivation of Hilpda. Taken together, we find that HILPDA is highly abundant in adipose tissue, where its levels are induced by peroxisome proliferator-activated receptor γ and β-adrenergic stimulation. In contrast to the reported inhibition of lipolysis by HILPDA in hepatocytes, our data do not support an important direct role of HILPDA in the regulation of lipolysis in adipocytes in vivo and in vitro.
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Affiliation(s)
- Wieneke Dijk
- Nutrition, Metabolism, and Genomics Group, Division of Human Nutrition, Wageningen University, 6708 WE Wageningen, The Netherlands
| | - Frits Mattijssen
- Nutrition, Metabolism, and Genomics Group, Division of Human Nutrition, Wageningen University, 6708 WE Wageningen, The Netherlands
| | - Montserrat de la Rosa Rodriguez
- Nutrition, Metabolism, and Genomics Group, Division of Human Nutrition, Wageningen University, 6708 WE Wageningen, The Netherlands
| | - Angel Loza Valdes
- Nutrition, Metabolism, and Genomics Group, Division of Human Nutrition, Wageningen University, 6708 WE Wageningen, The Netherlands
| | - Anne Loft
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, DK-5230 Odense, Denmark
| | - Susanne Mandrup
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, DK-5230 Odense, Denmark
| | - Eric Kalkhoven
- Molecular Cancer Research and Center for Molecular Medicine, University Medical Centre Utrecht, 3584 CG Utrecht, The Netherlands
| | - Ling Qi
- University of Michigan Medical School, Ann Arbor, Michigan 48105
| | - Jan Willem Borst
- Laboratory of Biochemistry, Microspectroscopy Centre, Wageningen University, 6708 WE Wageningen, The Netherlands
| | - Sander Kersten
- Nutrition, Metabolism, and Genomics Group, Division of Human Nutrition, Wageningen University, 6708 WE Wageningen, The Netherlands
- University of Michigan Medical School, Ann Arbor, Michigan 48105
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Sim CK, Kim SY, Brunmeir R, Zhang Q, Li H, Dharmasegaran D, Leong C, Lim YY, Han W, Xu F. Regulation of white and brown adipocyte differentiation by RhoGAP DLC1. PLoS One 2017; 12:e0174761. [PMID: 28358928 PMCID: PMC5373604 DOI: 10.1371/journal.pone.0174761] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Accepted: 03/15/2017] [Indexed: 12/22/2022] Open
Abstract
Adipose tissues constitute an important component of metabolism, the dysfunction of which can cause obesity and type II diabetes. Here we show that differentiation of white and brown adipocytes requires Deleted in Liver Cancer 1 (DLC1), a Rho GTPase Activating Protein (RhoGAP) previously studied for its function in liver cancer. We identified Dlc1 as a super-enhancer associated gene in both white and brown adipocytes through analyzing the genome-wide binding profiles of PPARγ, the master regulator of adipogenesis. We further observed that Dlc1 expression increases during differentiation, and knockdown of Dlc1 by siRNA in white adipocytes reduces the formation of lipid droplets and the expression of fat marker genes. Moreover, knockdown of Dlc1 in brown adipocytes reduces expression of brown fat-specific genes and diminishes mitochondrial respiration. Dlc1-/- knockout mouse embryonic fibroblasts show a complete inability to differentiate into adipocytes, but this phenotype can be rescued by inhibitors of Rho-associated kinase (ROCK) and filamentous actin (F-actin), suggesting the involvement of Rho pathway in DLC1-regulated adipocyte differentiation. Furthermore, PPARγ binds to the promoter of Dlc1 gene to regulate its expression during both white and brown adipocyte differentiation. These results identify DLC1 as an activator of white and brown adipocyte differentiation, and provide a molecular link between PPARγ and Rho pathways.
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Affiliation(s)
- Choon Kiat Sim
- Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A*STAR), Singapore
| | - Sun-Yee Kim
- Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A*STAR), Singapore
- Laboratory of Metabolic Medicine, Singapore Bioimaging Consortium, A*STAR, Singapore
| | - Reinhard Brunmeir
- Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A*STAR), Singapore
| | - Qiongyi Zhang
- Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A*STAR), Singapore
| | - Hongyu Li
- Laboratory of Metabolic Medicine, Singapore Bioimaging Consortium, A*STAR, Singapore
| | - Dharmini Dharmasegaran
- Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A*STAR), Singapore
| | - Carol Leong
- Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A*STAR), Singapore
| | - Ying Yan Lim
- Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A*STAR), Singapore
| | - Weiping Han
- Laboratory of Metabolic Medicine, Singapore Bioimaging Consortium, A*STAR, Singapore
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Feng Xu
- Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A*STAR), Singapore
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- * E-mail:
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25
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Wang S, Dougherty EJ, Danner RL. PPARγ signaling and emerging opportunities for improved therapeutics. Pharmacol Res 2016; 111:76-85. [PMID: 27268145 DOI: 10.1016/j.phrs.2016.02.028] [Citation(s) in RCA: 139] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 02/29/2016] [Indexed: 01/23/2023]
Abstract
Peroxisome proliferator-activated receptor gamma (PPARγ) is a ligand-activated nuclear receptor that regulates glucose and lipid metabolism, endothelial function and inflammation. Rosiglitazone (RGZ) and other thiazolidinedione (TZD) synthetic ligands of PPARγ are insulin sensitizers that have been used for the treatment of type 2 diabetes. However, undesirable side effects including weight gain, fluid retention, bone loss, congestive heart failure, and a possible increased risk of myocardial infarction and bladder cancer, have limited the use of TZDs. Therefore, there is a need to better understand PPARγ signaling and to develop safer and more effective PPARγ-directed therapeutics. In addition to PPARγ itself, many PPARγ ligands including TZDs bind to and activate G protein-coupled receptor 40 (GPR40), also known as free fatty acid receptor 1. GPR40 signaling activates stress kinase pathways that ultimately regulate downstream PPARγ responses. Recent studies in human endothelial cells have demonstrated that RGZ activation of GPR40 is essential to the optimal propagation of PPARγ genomic signaling. RGZ/GPR40/p38 MAPK signaling induces and activates PPARγ co-activator-1α, and recruits E1A binding protein p300 to the promoters of target genes, markedly enhancing PPARγ-dependent transcription. Therefore in endothelium, GPR40 and PPARγ function as an integrated signaling pathway. However, GPR40 can also activate ERK1/2, a proinflammatory kinase that directly phosphorylates and inactivates PPARγ. Thus the role of GPR40 in PPARγ signaling may have important implications for drug development. Ligands that strongly activate PPARγ, but do not bind to or activate GPR40 may be safer than currently approved PPARγ agonists. Alternatively, biased GPR40 agonists might be sought that activate both p38 MAPK and PPARγ, but not ERK1/2, avoiding its harmful effects on PPARγ signaling, insulin resistance and inflammation. Such next generation drugs might be useful in treating not only type 2 diabetes, but also diverse chronic and acute forms of vascular inflammation such as atherosclerosis and septic shock.
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Affiliation(s)
- Shuibang Wang
- Critical Care Medicine Department, Clinical Center, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Edward J Dougherty
- Critical Care Medicine Department, Clinical Center, National Institutes of Health, Bethesda, MD 20892, USA
| | - Robert L Danner
- Critical Care Medicine Department, Clinical Center, National Institutes of Health, Bethesda, MD 20892, USA.
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26
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Khan MZ, He L, Zhuang X. The emerging role of GPR50 receptor in brain. Biomed Pharmacother 2016; 78:121-128. [PMID: 26898433 DOI: 10.1016/j.biopha.2016.01.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2015] [Accepted: 01/06/2016] [Indexed: 01/08/2023] Open
Abstract
GPR50 receptor one of the member of G protein-coupled receptors (GPCRs) is extensively expressed in the pituitary, hypothalamus,cortex, midbrain, pons, amygdala, and in several brainstem nuclei. The exact function of this receptor in brain is remains unclear. This review presents current knowledge regarding the function of GPR50 receptor in brain, with a focus on role of this receptor in the hypothalamus-pituitary-adrenal (HPA) axis and the glucocorticoid receptor (GR) signaling, leptin signaling, adaptive thermogenesis, torpor, neurite outgrowth, and self-renewal and neuronal differentiation of neural progenitor cells NPCs. Although the results are encouraging, further research is needed to clarify GPR50 role in neurobiology of mood disorders, adaptive thermogenesis, torpor, and in the pathophysiology of neurological disorders.
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Affiliation(s)
- Muhammad Zahid Khan
- Department of Pharmacology, China Pharmaceutical University, Nanjing 210009, China.
| | - Ling He
- China Pharmaceutical University, Department of Pharmacology, No. 24 Tong Jia Xiang, Nanjing,Jiang Su Province 210009, China
| | - Xuxu Zhuang
- China Pharmaceutical University, Department of Pharmacology, No. 24 Tong Jia Xiang, Nanjing,Jiang Su Province 210009, China
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27
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Epigenetic landscape in PPARγ2 in the enhancement of adipogenesis of mouse osteoporotic bone marrow stromal cell. Biochim Biophys Acta Mol Basis Dis 2015; 1852:2504-16. [DOI: 10.1016/j.bbadis.2015.08.020] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2015] [Revised: 08/21/2015] [Accepted: 08/24/2015] [Indexed: 11/21/2022]
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28
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Renga B, Francisci D, Carino A, Marchianò S, Cipriani S, Chiara Monti M, Del Sordo R, Schiaroli E, Distrutti E, Baldelli F, Fiorucci S. The HIV matrix protein p17 induces hepatic lipid accumulation via modulation of nuclear receptor transcriptoma. Sci Rep 2015; 5:15403. [PMID: 26469385 PMCID: PMC4606811 DOI: 10.1038/srep15403] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Accepted: 09/18/2015] [Indexed: 02/06/2023] Open
Abstract
Liver disease is the second most common cause of mortality in HIV-infected persons. Exactly how HIV infection per se affects liver disease progression is unknown. Here we have investigated mRNA expression of 49 nuclear hormone receptors (NRs) and 35 transcriptional coregulators in HepG2 cells upon stimulation with the HIV matrix protein p17. This viral protein regulated mRNA expression of some NRs among which LXRα and its transcriptional co-activator MED1 were highly induced at mRNA level. Dissection of p17 downstream intracellular pathway demonstrated that p17 mediated activation of Jak/STAT signaling is responsible for the promoter dependent activation of LXR. The treatment of both HepG2 as well as primary hepatocytes with HIV p17 results in the transcriptional activation of LXR target genes (SREBP1c and FAS) and lipid accumulation. These effects are lost in HepG2 cells pre-incubated with a serum from HIV positive person who underwent a vaccination with a p17 peptide as well as in HepG2 cells pre-incubated with the natural LXR antagonist gymnestrogenin. These results suggest that HIV p17 affects NRs and their related signal transduction thus contributing to the progression of liver disease in HIV infected patients.
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Affiliation(s)
- Barbara Renga
- Department of Surgical and Biomedical Sciences, Section of gastroenterology, University of Perugia, Perugia, Italy
| | - Daniela Francisci
- Department of Medicine, Section of Infectious diseases, University of Perugia, Perugia, Italy
| | - Adriana Carino
- Department of Surgical and Biomedical Sciences, Section of gastroenterology, University of Perugia, Perugia, Italy
| | - Silvia Marchianò
- Department of Surgical and Biomedical Sciences, Section of gastroenterology, University of Perugia, Perugia, Italy
| | - Sabrina Cipriani
- Department of Medicine, Section of Infectious diseases, University of Perugia, Perugia, Italy
| | - Maria Chiara Monti
- Department of Biomedical and Pharmaceutical Sciences, University of Salerno, Fisciano, Italy
| | - Rachele Del Sordo
- Department of Experimental Medicine and Biochemical Sciences, Section of Anatomic Pathology and Histology, University of Perugia, Perugia, Italy
| | - Elisabetta Schiaroli
- Department of Medicine, Section of Infectious diseases, University of Perugia, Perugia, Italy
| | | | - Franco Baldelli
- Department of Medicine, Section of Infectious diseases, University of Perugia, Perugia, Italy
| | - Stefano Fiorucci
- Department of Surgical and Biomedical Sciences, Section of gastroenterology, University of Perugia, Perugia, Italy
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29
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Huang B, Li G, Jiang XH. Fate determination in mesenchymal stem cells: a perspective from histone-modifying enzymes. Stem Cell Res Ther 2015; 6:35. [PMID: 25890062 PMCID: PMC4365520 DOI: 10.1186/s13287-015-0018-0] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Mesenchymal stem cells (MSCs) hold great promise for therapeutic use in regenerative medicine and tissue engineering. A detailed understanding of the molecular processes governing MSC fate determination will be instrumental in the application of MSCs. Much progress has been made in recent years in defining the epigenetic events that control the differentiation of MSCs into different lineages. A complex network of transcription factors and histone modifiers, in concert with specific transcriptional co-activators and co-repressors, activates or represses MSC differentiation. In this review, we summarize recent progress in determining the effects of histone-modifying enzymes on the multilineage differentiation of MSCs. In addition, we propose that the manipulation of histone signatures associated with lineage-specific differentiation by small molecules has immense potential for the advancement of MSC-based regenerative medicine.
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Affiliation(s)
- Biao Huang
- Key Laboratory for Regenerative Medicine, Ministry of Education, Epithelial Cell Biology Research Centre, School of Biomedical Sciences, Lo Kwee-Seong Integrated Biomedical Sciences Building, Shatin, New Territories, Hong Kong, PR China.
| | - Gang Li
- Department of Orthopaedics & Traumatology, Li Ka Shing Institute of Health Science, Prince of Wales Hospital, 30-32 Ngan Shing Street, Shatin, New Territories, Hong Kong, PR China. .,Lui Che Woo Institute of Innovative Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, SAR, China. .,School of Biomedical Sciences Core Laboratory, The Chinese University of Hong Kong Shenzhen Research Institute, Shenzhen, 518057, China.
| | - Xiao Hua Jiang
- Key Laboratory for Regenerative Medicine, Ministry of Education, Epithelial Cell Biology Research Centre, School of Biomedical Sciences, Lo Kwee-Seong Integrated Biomedical Sciences Building, Shatin, New Territories, Hong Kong, PR China. .,Lui Che Woo Institute of Innovative Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, SAR, China. .,School of Biomedical Sciences Core Laboratory, The Chinese University of Hong Kong Shenzhen Research Institute, Shenzhen, 518057, China.
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30
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Rakhshandehroo M, Gijzel SMW, Siersbæk R, Broekema MF, de Haar C, Schipper HS, Boes M, Mandrup S, Kalkhoven E. CD1d-mediated presentation of endogenous lipid antigens by adipocytes requires microsomal triglyceride transfer protein. J Biol Chem 2014; 289:22128-39. [PMID: 24966328 DOI: 10.1074/jbc.m114.551242] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Obesity-induced adipose tissue (AT) dysfunction results in a chronic low-grade inflammation that predisposes to the development of insulin resistance and type 2 diabetes. During the development of obesity, the AT-resident immune cell profile alters to create a pro-inflammatory state. Very recently, CD1d-restricted invariant (i) natural killer T (NKT) cells, a unique subset of lymphocytes that are reactive to so called lipid antigens, were implicated in AT homeostasis. Interestingly, recent data also suggest that human and mouse adipocytes can present such lipid antigens to iNKT cells in a CD1d-dependent fashion, but little is known about the lipid antigen presentation machinery in adipocytes. Here we show that CD1d, as well as the lipid antigen loading machinery genes pro-saposin (Psap), Niemann Pick type C2 (Npc2), α-galactosidase (Gla), are up-regulated in early adipogenesis, and are transcriptionally controlled by CCAAT/enhancer-binding protein (C/EBP)-β and -δ. Moreover, adipocyte-induced Th1 and Th2 cytokine release by iNKT cells also occurred in the absence of exogenous ligands, suggesting the display of endogenous lipid antigen-D1d complexes by 3T3-L1 adipocytes. Furthermore, we identified microsomal triglyceride transfer protein, which we show is also under the transcriptional regulation of C/EBPβ and -δ, as a novel player in the presentation of endogenous lipid antigens by adipocytes. Overall, our findings indicate that adipocytes can function as non-professional lipid antigen presenting cells, which may present an important aspect of adipocyte-immune cell communication in the regulation of whole body energy metabolism and immune homeostasis.
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Affiliation(s)
| | - Sanne M W Gijzel
- From the Molecular Cancer Research, Center for Molecular Medicine and
| | - Rasmus Siersbæk
- the Department of Biochemistry and Molecular Biology, University of Southern Denmark, DK-5230 Odense, Denmark
| | | | - Colin de Haar
- the Department of Pediatric Immunology, University Medical Center Utrecht, 3584 CG Utrecht, the Netherlands and
| | - Henk S Schipper
- From the Molecular Cancer Research, Center for Molecular Medicine and the Department of Pediatric Immunology, University Medical Center Utrecht, 3584 CG Utrecht, the Netherlands and
| | - Marianne Boes
- the Department of Pediatric Immunology, University Medical Center Utrecht, 3584 CG Utrecht, the Netherlands and
| | - Susanne Mandrup
- the Department of Biochemistry and Molecular Biology, University of Southern Denmark, DK-5230 Odense, Denmark
| | - Eric Kalkhoven
- From the Molecular Cancer Research, Center for Molecular Medicine and
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31
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Gao Y, Hamers N, Rakhshandehroo M, Berger R, Lough J, Kalkhoven E. Allele compensation in tip60+/- mice rescues white adipose tissue function in vivo. PLoS One 2014; 9:e98343. [PMID: 24870614 PMCID: PMC4037199 DOI: 10.1371/journal.pone.0098343] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Accepted: 05/01/2014] [Indexed: 01/14/2023] Open
Abstract
Adipose tissue is a key regulator of energy homestasis. The amount of adipose tissue is largely determined by adipocyte differentiation (adipogenesis), a process that is regulated by the concerted actions of multiple transcription factors and cofactors. Based on in vitro studies in murine 3T3-L1 preadipocytes and human primary preadipocytes, the transcriptional cofactor and acetyltransferase Tip60 was recently identified as an essential adipogenic factor. We therefore investigated the role of Tip60 on adipocyte differentiation and function, and possible consequences on energy homeostasis, in vivo. Because homozygous inactivation results in early embryonic lethality, Tip60+/− mice were used. Heterozygous inactivation of Tip60 had no effect on body weight, despite slightly higher food intake by Tip60+/− mice. No major effects of heterozygous inactivation of Tip60 were observed on adipose tissue and liver, and Tip60+/− displayed normal glucose tolerance, both on a low fat and a high fat diet. While Tip60 mRNA was reduced to 50% in adipose tissue, the protein levels were unaltered, suggesting compensation by the intact allele. These findings indicate that the in vivo role of Tip60 in adipocyte differentiation and function cannot be properly addressed in Tip60+/− mice, but requires the generation of adipose tissue-specific knock out animals or specific knock-in mice.
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Affiliation(s)
- Yuan Gao
- Molecular Cancer Research, Center for Molecular Medicine, University Medical Centre Utrecht, Utrecht, The Netherlands
- Netherlands Metabolomics Center, Leiden, The Netherlands
| | - Nicole Hamers
- Molecular Cancer Research, Center for Molecular Medicine, University Medical Centre Utrecht, Utrecht, The Netherlands
- Netherlands Metabolomics Center, Leiden, The Netherlands
| | - Maryam Rakhshandehroo
- Molecular Cancer Research, Center for Molecular Medicine, University Medical Centre Utrecht, Utrecht, The Netherlands
| | - Ruud Berger
- Molecular Cancer Research, Center for Molecular Medicine, University Medical Centre Utrecht, Utrecht, The Netherlands
- Netherlands Metabolomics Center, Leiden, The Netherlands
| | - John Lough
- Department of Cell Biology, Neurobiology and Anatomy and the Cardiovascular Center, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
| | - Eric Kalkhoven
- Molecular Cancer Research, Center for Molecular Medicine, University Medical Centre Utrecht, Utrecht, The Netherlands
- Netherlands Metabolomics Center, Leiden, The Netherlands
- * E-mail:
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32
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Early adipogenesis is regulated through USP7-mediated deubiquitination of the histone acetyltransferase TIP60. Nat Commun 2014; 4:2656. [PMID: 24141283 DOI: 10.1038/ncomms3656] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Accepted: 09/23/2013] [Indexed: 01/27/2023] Open
Abstract
Transcriptional coregulators, including the acetyltransferase Tip60, have a key role in complex cellular processes such as differentiation. Whereas post-translational modifications have emerged as an important mechanism to regulate transcriptional coregulator activity, the identification of the corresponding demodifying enzymes has remained elusive. Here we show that the expression of the Tip60 protein, which is essential for adipocyte differentiation, is regulated through polyubiquitination on multiple residues. USP7, a dominant deubiquitinating enzyme in 3T3-L1 adipocytes and mouse adipose tissue, deubiquitinates Tip60 both in intact cells and in vitro and increases Tip60 protein levels. Furthermore, inhibition of USP7 expression and activity decreases adipogenesis. Transcriptome analysis reveals several cell cycle genes to be co-regulated by both Tip60 and USP7. Knockdown of either factor results in impaired mitotic clonal expansion, an early step in adipogenesis. These results reveal deubiquitination of a transcriptional coregulator to be a key mechanism in the regulation of early adipogenesis.
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33
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Gao Y, Kalkhoven E. TIPping the balance in adipogenesis: USP7-mediated stabilization of Tip60. Adipocyte 2014; 3:160-5. [PMID: 24719792 DOI: 10.4161/adip.28307] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/29/2013] [Revised: 02/20/2014] [Accepted: 02/20/2014] [Indexed: 01/19/2023] Open
Abstract
Adipogenesis is regulated by a complex interplay between transcription factors, in concert with-among others-transcriptional cofactors, signaling cascades and miRNAs. Several studies have implicated the transcriptional cofactor and acetyltransferase Tip60 in PPARγ signaling and adipocyte differentiation. Since Tip60 protein levels, but not mRNA levels, are upregulated during adipogenesis, and since Tip60 can be degraded by the proteasome, we hypothesized that Tip60 protein may be stabilized through deubiquitination during adipogenesis. Indeed, Tip60 is protected from proteasomal degeradation by the deubiquitinase USP7, which is particularly important for mitotic clonal expansion (MCE), an early step in adipogenesis. Besides this novel role in early differentiation, earlier studies indicated that Tip60 is also important during the later stages of differentiation, indicating a dual role for this protein in adipogenesis. Our recent study sheds new light on the role of Tip60 in cellular differentiation and provide new insights into the importance of a regulatory process that has not been studied intensively in adipogenesis: protein (de)ubiquitination.
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Role of histone acetyltransferases and histone deacetylases in adipocyte differentiation and adipogenesis. Eur J Cell Biol 2014; 93:170-7. [PMID: 24810880 DOI: 10.1016/j.ejcb.2014.03.001] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Revised: 03/07/2014] [Accepted: 03/13/2014] [Indexed: 01/14/2023] Open
Abstract
Adipogenesis is a complex process strictly regulated by a well-established cascade that has been thoroughly studied in the last two decades. This process is governed by complex regulatory networks that involve the activation/inhibition of multiple functional genes, and is controlled by histone-modifying enzymes. Among such modification enzymes, histone acetyltransferases (HATs) and histone deacetylases (HDACs) play important roles in the transcriptional regulation and post-translational modification of protein acetylation. HATs and HDACs have been shown to respond to signals that regulate cell differentiation, participate in the regulation of protein acetylation, mediate transcription and post-translation modifications, and directly acetylate/deacetylate various transcription factors and regulatory proteins. In this paper, we review the role of HATs and HDACs in white and brown adipocyte differentiation and adipogenesis, to expand our knowledge on fat formation and adipose tissue biology.
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35
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Zhang SM, Zhu LH, Li ZZ, Wang PX, Chen HZ, Guan HJ, Jiang DS, Chen K, Zhang XF, Tian S, Yang D, Zhang XD, Li H. Interferon regulatory factor 3 protects against adverse neo-intima formation. Cardiovasc Res 2014; 102:469-79. [DOI: 10.1093/cvr/cvu052] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
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36
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Tasdelen I, Berger R, Kalkhoven E. PPARγ regulates expression of carbohydrate sulfotransferase 11 (CHST11/C4ST1), a regulator of LPL cell surface binding. PLoS One 2013; 8:e64284. [PMID: 23696875 PMCID: PMC3655946 DOI: 10.1371/journal.pone.0064284] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2012] [Accepted: 04/12/2013] [Indexed: 01/09/2023] Open
Abstract
The transcription factor PPARγ is the key regulator of adipocyte differentiation, function and maintenance, and the cellular target of the insulin-sensitizing thiazolidinediones. Identification and functional characterization of genes regulated by PPARγ will therefore lead to a better understanding of adipocyte biology and may also contribute to the development of new anti-diabetic drugs. Here, we report carbohydrate sulfotransferase 11 (Chst11/C4st1) as a novel PPARγ target gene. Chst11 can sulphate chondroitin, a major glycosaminoglycan involved in development and disease. The Chst11 gene contains two functional intronic PPARγ binding sites, and is up-regulated at the mRNA and protein level during 3T3-L1 adipogenesis. Chst11 knockdown reduced intracellular lipid accumulation in mature adipocytes, which is due to a lowered activity of lipoprotein lipase, which may associate with the adipocyte cell surface through Chst11-mediated sulfation of chondroitin, rather than impaired adipogenesis. Besides directly inducing Lpl expression, PPARγ may therefore control lipid accumulation by elevating the levels of Chst11-mediated proteoglycan sulfation and thereby increasing the binding capacity for Lpl on the adipocyte cell surface.
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Affiliation(s)
- Ismayil Tasdelen
- Department of Metabolic Diseases and The Netherlands Metabolomics Center, University Medical Centre Utrecht, Utrecht, The Netherlands
| | - Ruud Berger
- Department of Metabolic Diseases and The Netherlands Metabolomics Center, University Medical Centre Utrecht, Utrecht, The Netherlands
| | - Eric Kalkhoven
- Department of Metabolic Diseases and The Netherlands Metabolomics Center, University Medical Centre Utrecht, Utrecht, The Netherlands
- * E-mail:
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37
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The serine/threonine phosphatase PPM1B (PP2Cβ) selectively modulates PPARγ activity. Biochem J 2013; 451:45-53. [PMID: 23320500 DOI: 10.1042/bj20121113] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Reversible phosphorylation is a widespread molecular mechanism to regulate the function of cellular proteins, including transcription factors. Phosphorylation of the nuclear receptor PPARγ (peroxisome-proliferator-activated receptor γ) at two conserved serine residue (Ser(112) and Ser(273)) results in an altered transcriptional activity of this transcription factor. So far, only a very limited number of cellular enzymatic activities has been described which can dephosphorylate nuclear receptors. In the present study we used immunoprecipitation assays coupled to tandem MS analysis to identify novel PPARγ-regulating proteins. We identified the serine/threonine phosphatase PPM1B [PP (protein phosphatase), Mg(2+)/Mn(2+) dependent, 1B; also known as PP2Cβ] as a novel PPARγ-interacting protein. Endogenous PPM1B protein is localized in the nucleus of mature 3T3-L1 adipocytes where it can bind to PPARγ. Furthermore we show that PPM1B can directly dephosphorylate PPARγ, both in intact cells and in vitro. In addition PPM1B increases PPARγ-mediated transcription via dephosphorylation of Ser(112). Finally, we show that knockdown of PPM1B in 3T3-L1 adipocytes blunts the expression of some PPARγ target genes while leaving others unaltered. These findings qualify the phosphatase PPM1B as a novel selective modulator of PPARγ activity.
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Mul JD, O’Duibhir E, Shrestha YB, Koppen A, Vargoviç P, Toonen PW, Zarebidaki E, Kvetnansky R, Kalkhoven E, Cuppen E, Bartness TJ. Pmch-deficiency in rats is associated with normal adipocyte differentiation and lower sympathetic adipose drive. PLoS One 2013; 8:e60214. [PMID: 23555928 PMCID: PMC3608591 DOI: 10.1371/journal.pone.0060214] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2013] [Accepted: 02/22/2013] [Indexed: 02/01/2023] Open
Abstract
The orexigenic neuropeptide melanin-concentrating hormone (MCH), a product of Pmch, is an important mediator of energy homeostasis. Pmch-deficient rodents are lean and smaller, characterized by lower food intake, body-, and fat mass. Pmch is expressed in hypothalamic neurons that ultimately are components in the sympathetic nervous system (SNS) drive to white and interscapular brown adipose tissue (WAT, iBAT, respectively). MCH binds to MCH receptor 1 (MCH1R), which is present on adipocytes. Currently it is unknown if Pmch-ablation changes adipocyte differentiation or sympathetic adipose drive. Using Pmch-deficient and wild-type rats on a standard low-fat diet, we analyzed dorsal subcutaneous and perirenal WAT mass and adipocyte morphology (size and number) throughout development, and indices of sympathetic activation in WAT and iBAT during adulthood. Moreover, using an in vitro approach we investigated the ability of MCH to modulate 3T3-L1 adipocyte differentiation. Pmch-deficiency decreased dorsal subcutaneous and perirenal WAT mass by reducing adipocyte size, but not number. In line with this, in vitro 3T3-L1 adipocyte differentiation was unaffected by MCH. Finally, adult Pmch-deficient rats had lower norepinephrine turnover (an index of sympathetic adipose drive) in WAT and iBAT than wild-type rats. Collectively, our data indicate that MCH/MCH1R-pathway does not modify adipocyte differentiation, whereas Pmch-deficiency in laboratory rats lowers adiposity throughout development and sympathetic adipose drive during adulthood.
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Affiliation(s)
- Joram D. Mul
- Hubrecht Institute-KNAW and University Medical Center Utrecht, Utrecht, The Netherlands
| | - Eoghan O’Duibhir
- Hubrecht Institute-KNAW and University Medical Center Utrecht, Utrecht, The Netherlands
| | - Yogendra B. Shrestha
- Department of Biology, Neurobiology and Behavior Program, and Exploring and Testing Strategies for Obesity Reversal Center, Georgia State University, Atlanta, Georgia, United States of America
| | - Arjen Koppen
- Department of Metabolic and Endocrine Diseases, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Peter Vargoviç
- Laboratory for Stress Research, Institute of Experimental Endocrinology, Bratislava, Slovakia
| | - Pim W. Toonen
- Hubrecht Institute-KNAW and University Medical Center Utrecht, Utrecht, The Netherlands
| | - Eleen Zarebidaki
- Department of Biology, Neurobiology and Behavior Program, and Exploring and Testing Strategies for Obesity Reversal Center, Georgia State University, Atlanta, Georgia, United States of America
| | - Richard Kvetnansky
- Laboratory for Stress Research, Institute of Experimental Endocrinology, Bratislava, Slovakia
| | - Eric Kalkhoven
- Department of Metabolic and Endocrine Diseases, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Edwin Cuppen
- Hubrecht Institute-KNAW and University Medical Center Utrecht, Utrecht, The Netherlands
- Department of Medical Genetics, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Timothy J. Bartness
- Department of Biology, Neurobiology and Behavior Program, and Exploring and Testing Strategies for Obesity Reversal Center, Georgia State University, Atlanta, Georgia, United States of America
- * E-mail:
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Adipogenic/lipid, inflammatory, and mitochondrial parameters in subcutaneous adipose tissue of untreated HIV-1-infected long-term nonprogressors: significant alterations despite low viral burden. J Acquir Immune Defic Syndr 2012; 61:131-7. [PMID: 22580565 DOI: 10.1097/qai.0b013e31825c3a68] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND HIV-1 can induce disturbances in adipose tissue in infected subjects through the effects of some of its proteins or inflammation. It is not known whether this also takes place in HIV-1-infected long-term nonprogressors (LTNPs). Our objectives were to determine whether adipocyte differentiation/lipid, inflammatory, and mitochondrial parameters are perturbed in abdominal wall subcutaneous adipose tissue of untreated HIV-1-infected patients LTNPs. METHODS Cross-sectional study involving 10 LTNPs, 10 typical progressors (TPs), and 10 uninfected controls (UCs). The parameters assessed were peroxisome proliferator-activated receptor-gamma (PPARγ), lipoprotein lipase, and fatty acid-binding protein 4 mRNA (adipogenic/lipid); tumor necrosis factor-alpha, interleukin 18 (IL-18), β2-MCG, monocyte chemoattractant protein 1, CD1A, and C3 mRNA (inflammation); and cytochrome c oxidase subunit II (COII), COIV, CYCA, nuclear respiratory factor 1, PPARγ coactivator 1α mRNA, and mtDNA content (mitochondrial). RESULTS Regarding adipogenic/lipid parameters, LTNPs had PPARγ, lipoprotein lipase, and fatty acid-binding protein 4 mRNA significantly decreased compared with UCs (P ≤ 0.001 for all comparisons). PPARγ mRNA was significantly greater in LTNP than in TP (P = 0.006). With respect to inflammatory parameters, tumor necrosis factor-alpha, IL-18, and β2-MCG mRNA were significantly higher in LTNPs compared with UCs (P < 0.005 for all comparisons), whereas IL-18 mRNA was greater in TPs compared with LTNPs (P = 0.01). As mitochondrial parameters are concerned, mtDNA was significantly reduced in LTNPs compared with TPs (P = 0.04) and UCs (P = 0.03). COII and COIV were also significantly reduced in LTNPs compared with UCs and TPs. CONCLUSIONS Adipose tissue from untreated LTNPs may have limited but significant derangements in some adipogenic/lipid and may have inflammatory processes at a lower degree than that observed in untreated TPs. LTNPs may have mitochondrial-related alterations in adipose tissue which are greater than that observed in TPs.
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Couture JP, Nolet G, Beaulieu E, Blouin R, Gévry N. The p400/Brd8 chromatin remodeling complex promotes adipogenesis by incorporating histone variant H2A.Z at PPARγ target genes. Endocrinology 2012; 153:5796-808. [PMID: 23064015 DOI: 10.1210/en.2012-1380] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Adipogenesis, the biological process by which preadipocytes differentiate into mature fat cells, is coordinated by a tightly regulated gene expression program. Indeed, it has been reported that a large number of genetic events, from fat cell-specific transcription factors expression, such as the master regulator of fat cell differentiation peroxisome proliferator-activated receptor (PPAR)γ2 to epigenetic modifications, govern the acquisition of a mature adipocyte phenotype. Here, we provide evidence that the E1A-binding protein p400 (p400) complex subunit bromo-containing protein 8 (Brd8) plays an important role in the regulation of PPARγ target genes during adipogenesis by targeting and incorporating the histone variant H2A.Z in transcriptional regulatory regions. The results reported here indicate that expression of both Brd8 and p400 increases during fat cell differentiation. In addition, small hairpin RNA-mediated knockdown of Brd8 or H2A.Z completely abrogated the ability of 3T3-L1 preadipocyte to differentiate into mature adipocyte, as evidenced by a lack of lipid accumulation. Chromatin immunoprecipitation experiments also revealed that the knockdown of Brd8 blocked the accumulation of PPARγ, p400, and RNA polymerase II and prevented the incorporation of H2A.Z at two PPARγ target genes. Taken together, these results indicate that the incorporation of the histone variant H2A.Z at the promoter regions of PPARγ target genes by p400/Brd8 is essential to allow fat cell differentiation.
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Affiliation(s)
- Jean-Philippe Couture
- Département de Biologie, Faculté des Sciences, Université de Sherbrooke, Sherbrooke, Québec, Canada J1K 2R1
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41
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Zhang Q, Ramlee MK, Brunmeir R, Villanueva CJ, Halperin D, Xu F. Dynamic and distinct histone modifications modulate the expression of key adipogenesis regulatory genes. Cell Cycle 2012; 11:4310-22. [PMID: 23085542 DOI: 10.4161/cc.22224] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Histone modifications and their modifying enzymes are fundamentally involved in the epigenetic regulation of adipogenesis. This study aimed to define the roles of various histone modifications and their "division of labor" in fat cell differentiation. To achieve these goals, we examined the distribution patterns of eight core histone modifications at five key adipogenic regulatory genes, Pref-1, C/EBPβ, C/EBPα, PPARγ2 and aP2, during the adipogenesis of C3H 10T1/2 mouse mesenchymal stem cells (MSCs) and 3T3-L1 preadipocytes. We found that the examined histone modifications are globally stable throughout adipogenesis but show distinct and highly dynamic distribution patterns at specific genes. For example, the Pref-1 gene has lower levels of active chromatin markers and significantly higher H3 K27 tri-methylation in MSCs compared with committed preadipocytes; the C/EBPβ gene is enriched in active chromatin markers at its 3'-UTR; the C/EBPα gene is predominantly marked by H3 K27 tri-methylation in adipogenic precursor cells, and this repressive marker decreases dramatically upon induction; the PPARγ2 and aP2 genes show increased histone acetylation on both H3 and H4 tails during adipogenesis. Further functional studies revealed that the decreased level of H3 K27 tri-methylation leads to de-repression of Pref-1 gene, while the increased level of histone acetylation activates the transcription of PPARγ2 and aP2 genes. Moreover, the active histone modification-marked 3'-UTR of C/EBPβ gene was demonstrated as a strong enhancer element by luciferase assay. Our results indicate that histone modifications are gene-specific at adipogenic regulator genes, and they play distinct roles in regulating the transcriptional network during adipogenesis.
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Affiliation(s)
- Qiongyi Zhang
- Growth, Development and Metabolism Programme; Singapore Institute for Clinical Sciences; A*STAR; Singapore
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42
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van Beekum O, Gao Y, Berger R, Koppen A, Kalkhoven E. A novel RNAi lethality rescue screen to identify regulators of adipogenesis. PLoS One 2012; 7:e37680. [PMID: 22679485 PMCID: PMC3367974 DOI: 10.1371/journal.pone.0037680] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2011] [Accepted: 04/25/2012] [Indexed: 01/14/2023] Open
Abstract
Adipogenesis, the differentiation of fibroblast-like mesenchymal stem cells into mature adipocytes, is tightly regulated by a complex cascade of transcription factors, including the nuclear receptor Peroxisome proliferator activator receptor γ (PPARγ). RNAi-mediated knock down libraries may present an atractive method for the identification of additional adipogenic factors. However, using in vitro adipogenesis model systems for high-throughput screening with siRNA libraries is limited since (i) differentiation is not homogeneous, but results in mixed cell populations, and (ii) the expression levels (and activity) of adipogenic regulators is highly dynamic during differentiation, indicating that the timing of RNAi-mediated knock down during differentiation may be extremely critical. Here we report a proof-of-principle for a novel RNAi screening method to identify regulators of adipogenesis that is based on lethality rescue rather than differentiation, using microRNA expression driven by a PPARγ responsive RNA polymerase II promoter. We validated this novel method through screening of a dedicated deubiquitinase knock down library, resulting in the identification of UCHL3 as an essential deubiquitinase in adipogenesis. This system therefore enables the identification of novel genes regulating PPARγ-mediated adipogenesis in a high-throughput setting.
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Affiliation(s)
- Olivier van Beekum
- Department of Metabolic Diseases, Netherlands Metabolomics Centre, University Medical Centre Utrecht, Utrecht, The Netherlands
| | - Yuan Gao
- Department of Metabolic Diseases, Netherlands Metabolomics Centre, University Medical Centre Utrecht, Utrecht, The Netherlands
| | - Ruud Berger
- Department of Metabolic Diseases, Netherlands Metabolomics Centre, University Medical Centre Utrecht, Utrecht, The Netherlands
| | - Arjen Koppen
- Department of Metabolic Diseases, Netherlands Metabolomics Centre, University Medical Centre Utrecht, Utrecht, The Netherlands
| | - Eric Kalkhoven
- Department of Metabolic Diseases, Netherlands Metabolomics Centre, University Medical Centre Utrecht, Utrecht, The Netherlands
- Centre for Molecular and Cellular Intervention, Wilhelmina Children’s Hospital, University Medical Centre Utrecht, Utrecht, The Netherlands
- * E-mail:
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43
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Zhang SM, Song M, Yang TY, Fan R, Liu XD, Zhou PK. HIV-1 Tat impairs cell cycle control by targeting the Tip60, Plk1 and cyclin B1 ternary complex. Cell Cycle 2012; 11:1217-34. [PMID: 22391203 DOI: 10.4161/cc.11.6.19664] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
HIV-1 Tat triggers intrinsic and extrinsic apoptosis pathways in both infected and uninfected cells and plays an important role in the pathogenesis of AIDS. Knocking down Tip60, an interactive protein of Tat, leads to the impairment of cell cycle progression, indicating a key role of Tip60 in cell cycle control. We found that Tip60 interacts with Plk1 through its ZnFMYST domain, and that this interaction is enhanced in the G 2/M phase. In addition, cyclin B1 was confirmed to interact with the ZnF domain of Tip60. Immunofluorescence imaging showed that Tip60 co-localizes with both Plk1 and cyclin B1 at the centrosome during the mitotic phase and to the mid-body during cytokinesis. Further experiments revealed that Tip60 forms a ternary complex with Plk1 and cyclin B1 and acetylates Plk1 but not cyclin B1. HIV-1 Tat likely forms a quaternary complex with Tip60, cyclin B1 and Plk1. Fluorescent microscopy showed that Tat causes an unscheduled nuclear translocation of both cyclin B1 and Plk1, causing their co-localization with Tip60 in the nucleus. Tat, Tip60, cyclin B1 and Plk1 interactions provide new a mechanistic explanation for Tat-mediated cell cycle dysregulation and apoptosis.
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Affiliation(s)
- Shi-Meng Zhang
- Department of Radiation Toxicology and Oncology, Beijing Institute of Radiation Medicine, Beijing, China
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Siersbæk R, Nielsen R, Mandrup S. Transcriptional networks and chromatin remodeling controlling adipogenesis. Trends Endocrinol Metab 2012; 23:56-64. [PMID: 22079269 DOI: 10.1016/j.tem.2011.10.001] [Citation(s) in RCA: 214] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2011] [Revised: 10/07/2011] [Accepted: 10/12/2011] [Indexed: 12/12/2022]
Abstract
Adipocyte differentiation is tightly controlled by a transcriptional cascade, which directs the extensive reprogramming of gene expression required to convert fibroblast-like precursor cells into mature lipid-laden adipocytes. Recent global analyses of transcription factor binding and chromatin remodeling have revealed 'snapshots' of this cascade and the chromatin landscape at specific time-points of differentiation. These studies demonstrate that multiple adipogenic transcription factors co-occupy hotspots characterized by an open chromatin structure and specific epigenetic modifications. Such transcription factor hotspots are likely to represent key signaling nodes which integrate multiple adipogenic signals at specific chromatin sites, thereby facilitating coordinated action on gene expression.
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Affiliation(s)
- Rasmus Siersbæk
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
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45
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Harmon GS, Lam MT, Glass CK. PPARs and lipid ligands in inflammation and metabolism. Chem Rev 2012; 111:6321-40. [PMID: 21988241 DOI: 10.1021/cr2001355] [Citation(s) in RCA: 113] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Gregory S Harmon
- Department of Medicine, Division of Digestive Diseases, University of California-Los Angeles, Los Angeles, California 90095, USA
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46
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Li J, Hand LE, Meng QJ, Loudon ASI, Bechtold DA. GPR50 interacts with TIP60 to modulate glucocorticoid receptor signalling. PLoS One 2011; 6:e23725. [PMID: 21858214 PMCID: PMC3157439 DOI: 10.1371/journal.pone.0023725] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2011] [Accepted: 07/26/2011] [Indexed: 11/25/2022] Open
Abstract
GPR50 is an orphan G-protein coupled receptor most closely related to the melatonin receptors. The physiological function of GPR50 remains unclear, although our previous studies implicate the receptor in energy homeostasis. Here, we reveal a role for GPR50 as a signalling partner and modulator of the transcriptional co-activator TIP60. This interaction was identified in a yeast-two-hybrid screen, and confirmed by co-immunoprecipitation and co-localisation of TIP60 and GPR50 in HEK293 cells. Co-expression with TIP60 increased perinuclear localisation of full length GPR50, and resulted in nuclear translocation of the cytoplasmic tail of the receptor, suggesting a functional interaction of the two proteins. We further demonstrate that GPR50 can enhance TIP60-coactiavtion of glucocorticoid receptor (GR) signalling. In line with in vitro results, repression of pituitary Pomc expression, and induction of gluconeogenic genes in liver in response to the GR agonist, dexamethasone was attenuated in Gpr50−/− mice. These results identify a novel role for GPR50 in glucocorticoid receptor signalling through interaction with TIP60.
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Affiliation(s)
- Jian Li
- Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom
| | - Laura E. Hand
- Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom
| | - Qing-Jun Meng
- Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom
| | - Andrew S. I. Loudon
- Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom
- * E-mail: (ASIL) (AL); (DAB) (DB)
| | - David A. Bechtold
- Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom
- * E-mail: (ASIL) (AL); (DAB) (DB)
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Chatterjee TK, Idelman G, Blanco V, Blomkalns AL, Piegore MG, Weintraub DS, Kumar S, Rajsheker S, Manka D, Rudich SM, Tang Y, Hui DY, Bassel-Duby R, Olson EN, Lingrel JB, Ho SM, Weintraub NL. Histone deacetylase 9 is a negative regulator of adipogenic differentiation. J Biol Chem 2011; 286:27836-47. [PMID: 21680747 DOI: 10.1074/jbc.m111.262964] [Citation(s) in RCA: 112] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Differentiation of preadipocytes into mature adipocytes capable of efficiently storing lipids is an important regulatory mechanism in obesity. Here, we examined the involvement of histone deacetylases (HDACs) and histone acetyltransferases (HATs) in the regulation of adipogenesis. We find that among the various members of the HDAC and HAT families, only HDAC9 exhibited dramatic down-regulation preceding adipogenic differentiation. Preadipocytes from HDAC9 gene knock-out mice exhibited accelerated adipogenic differentiation, whereas HDAC9 overexpression in 3T3-L1 preadipocytes suppressed adipogenic differentiation, demonstrating its direct role as a negative regulator of adipogenesis. HDAC9 expression was higher in visceral as compared with subcutaneous preadipocytes, negatively correlating with their potential to undergo adipogenic differentiation in vitro. HDAC9 localized in the nucleus, and its negative regulation of adipogenesis segregates with the N-terminal nuclear targeting domain, whereas the C-terminal deacetylase domain is dispensable for this function. HDAC9 co-precipitates with USF1 and is recruited with USF1 at the E-box region of the C/EBPα gene promoter in preadipocytes. Upon induction of adipogenic differentiation, HDAC9 is down-regulated, leading to its dissociation from the USF1 complex, whereas p300 HAT is up-regulated to allow its association with USF1 and accumulation at the E-box site of the C/EBPα promoter in differentiated adipocytes. This reciprocal regulation of HDAC9 and p300 HAT in the USF1 complex is associated with increased C/EBPα expression, a master regulator of adipogenic differentiation. These findings provide new insights into mechanisms of adipogenic differentiation and document a critical regulatory role for HDAC9 in adipogenic differentiation through a deacetylase-independent mechanism.
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Affiliation(s)
- Tapan K Chatterjee
- Department of Internal Medicine, Division of Cardiovascular Diseases, University of Cincinnati, Cincinnati, Ohio 45267, USA.
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Lorbeck M, Pirooznia K, Sarthi J, Zhu X, Elefant F. Microarray analysis uncovers a role for Tip60 in nervous system function and general metabolism. PLoS One 2011; 6:e18412. [PMID: 21494552 PMCID: PMC3073973 DOI: 10.1371/journal.pone.0018412] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2010] [Accepted: 03/07/2011] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND Tip60 is a key histone acetyltransferase (HAT) enzyme that plays a central role in diverse biological processes critical for general cell function; however, the chromatin-mediated cell-type specific developmental pathways that are dependent exclusively upon the HAT activity of Tip60 remain to be explored. METHODS AND FINDINGS Here, we investigate the role of Tip60 HAT activity in transcriptional control during multicellular development in vivo by examining genome-wide changes in gene expression in a Drosophila model system specifically depleted for endogenous dTip60 HAT function. CONCLUSIONS We show that amino acid residue E431 in the catalytic HAT domain of dTip60 is critical for the acetylation of endogenous histone H4 in our fly model in vivo, and demonstrate that dTip60 HAT activity is essential for multicellular development. Moreover, our results uncover a novel role for Tip60 HAT activity in controlling neuronal specific gene expression profiles essential for nervous system function as well as a central regulatory role for Tip60 HAT function in general metabolism.
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Affiliation(s)
- Meridith Lorbeck
- Department of Biology, Drexel University, Philadelphia, Pennsylvania, United States of America
| | - Keerthy Pirooznia
- Department of Biology, Drexel University, Philadelphia, Pennsylvania, United States of America
| | - Jessica Sarthi
- Department of Biology, Drexel University, Philadelphia, Pennsylvania, United States of America
| | - Xianmin Zhu
- Department of Biology, Drexel University, Philadelphia, Pennsylvania, United States of America
| | - Felice Elefant
- Department of Biology, Drexel University, Philadelphia, Pennsylvania, United States of America
- * E-mail:
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49
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A new protocol for functional analysis of adipogenesis using reverse transfection technology and time-lapse video microscopy. Cell Biol Int 2010; 34:737-46. [PMID: 20359292 DOI: 10.1042/cbi20090299] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Since the worldwide increase in obesity represents a growing challenge for healthcare systems, research focusing on fat cell metabolism has become a focal point of interest. Here, we describe a small interfering RNA (siRNA)-technology-based screening method to study fat cell differentiation in human primary preadipocytes that could be further developed towards an automated middle-throughput screening procedure. First, we established optimal conditions for the reverse transfection of human primary preadipocytes demonstrating that an efficient reverse transfection of preadipocytes is technically feasible. Aligning the processes of reverse transfection and fat cell differentiation utilizing peroxisome proliferator-activated receptor gamma (PPAR gamma)-siRNA, we showed that preadipocyte differentiation was suppressed by knock-down of PPAR gamma, the key regulator of fat cell differentiation. The use of fluorescently labelled fatty acids in combination with fluorescence time-lapse microscopy over a longer period of time enabled us to quantify the PPAR gamma phenotype. Additionally, our data demonstrate that reverse transfection of human cultured preadipocytes with TIP60 (HIV-1 Tat-interacting protein 60)-siRNA lead to a TIP60 knock-down and subsequently inhibits fat cell differentiation, suggesting a role of this protein in human adipogenesis. In conclusion, we established a protocol that allows for an efficient functional and time-dependent analysis by quantitative time-lapse microscopy to identify novel adipogenesis-associated genes.
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50
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Molecular Mechanisms and Genome-Wide Aspects of PPAR Subtype Specific Transactivation. PPAR Res 2010; 2010. [PMID: 20862367 PMCID: PMC2938449 DOI: 10.1155/2010/169506] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2010] [Accepted: 06/27/2010] [Indexed: 12/13/2022] Open
Abstract
The peroxisome proliferator-activated receptors (PPARs) are central regulators of fat metabolism, energy homeostasis, proliferation, and inflammation. The three PPAR subtypes, PPARα, β/δ, and γ activate overlapping but also very different target gene programs. This review summarizes the insights into PPAR subtype-specific transactivation provided by genome-wide studies and discusses the recent advances in the understanding of the molecular mechanisms underlying PPAR subtype specificity with special focus on the regulatory role of AF-1.
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