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Pouliou M, Koutsi MA, Champezou L, Giannopoulou AI, Vatsellas G, Piperi C, Agelopoulos M. MYCN Amplifications and Metabolic Rewiring in Neuroblastoma. Cancers (Basel) 2023; 15:4803. [PMID: 37835497 PMCID: PMC10571721 DOI: 10.3390/cancers15194803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 09/20/2023] [Accepted: 09/27/2023] [Indexed: 10/15/2023] Open
Abstract
Cancer is a disease caused by (epi)genomic and gene expression abnormalities and characterized by metabolic phenotypes that are substantially different from the normal phenotypes of the tissues of origin. Metabolic reprogramming is one of the key features of tumors, including those established in the human nervous system. In this work, we emphasize a well-known cancerous genomic alteration: the amplification of MYCN and its downstream effects in neuroblastoma phenotype evolution. Herein, we extend our previous computational biology investigations by conducting an integrative workflow applied to published genomics datasets and comprehensively assess the impact of MYCN amplification in the upregulation of metabolism-related transcription factor (TF)-encoding genes in neuroblastoma cells. The results obtained first emphasized overexpressed TFs, and subsequently those committed in metabolic cellular processes, as validated by gene ontology analyses (GOs) and literature curation. Several genes encoding for those TFs were investigated at the mechanistic and regulatory levels by conducting further omics-based computational biology assessments applied on published ChIP-seq datasets retrieved from MYCN-amplified- and MYCN-enforced-overexpression within in vivo systems of study. Hence, we approached the mechanistic interrelationship between amplified MYCN and overexpression of metabolism-related TFs in neuroblastoma and showed that many are direct targets of MYCN in an amplification-inducible fashion. These results illuminate how MYCN executes its regulatory underpinnings on metabolic processes in neuroblastoma.
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Affiliation(s)
- Marialena Pouliou
- Center of Basic Research, Biomedical Research Foundation, Academy of Athens, 4 Soranou Ephessiou St., 11527 Athens, Greece; (M.P.); (M.A.K.); (L.C.); (G.V.)
| | - Marianna A. Koutsi
- Center of Basic Research, Biomedical Research Foundation, Academy of Athens, 4 Soranou Ephessiou St., 11527 Athens, Greece; (M.P.); (M.A.K.); (L.C.); (G.V.)
| | - Lydia Champezou
- Center of Basic Research, Biomedical Research Foundation, Academy of Athens, 4 Soranou Ephessiou St., 11527 Athens, Greece; (M.P.); (M.A.K.); (L.C.); (G.V.)
| | - Angeliki-Ioanna Giannopoulou
- Department of Biological Chemistry, Medical School, National and Kapodistrian University of Athens, 75 M. Asias Street Bldg 16, 11527 Athens, Greece;
| | - Giannis Vatsellas
- Center of Basic Research, Biomedical Research Foundation, Academy of Athens, 4 Soranou Ephessiou St., 11527 Athens, Greece; (M.P.); (M.A.K.); (L.C.); (G.V.)
| | - Christina Piperi
- Department of Biological Chemistry, Medical School, National and Kapodistrian University of Athens, 75 M. Asias Street Bldg 16, 11527 Athens, Greece;
| | - Marios Agelopoulos
- Center of Basic Research, Biomedical Research Foundation, Academy of Athens, 4 Soranou Ephessiou St., 11527 Athens, Greece; (M.P.); (M.A.K.); (L.C.); (G.V.)
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Patsouras M, Alexopoulou E, Foutadakis S, Tsiki E, Karagianni P, Agelopoulos M, Vlachoyiannopoulos PG. Antiphospholipid antibodies induce proinflammatory and procoagulant pathways in endothelial cells. J Transl Autoimmun 2023; 6:100202. [PMID: 37216142 PMCID: PMC10197110 DOI: 10.1016/j.jtauto.2023.100202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 03/01/2023] [Accepted: 04/30/2023] [Indexed: 05/24/2023] Open
Abstract
Antiphospholipid syndrome (APS) is an autoimmune thrombophilia characterized by recurrent thrombotic events and/or pregnancy morbidity in the presence of antiphospholipid antibodies detected either as anti-cardiolipin, anti-β2 Glycoprotein I (anti-β2GPI) or Lupus anticoagulant (LA). Endothelial deregulation characterizes the syndrome. To address gene expression changes accompanying the development of autoimmune phenotype in endothelial cells in the context of APS, we performed transcriptomics analysis in Human Umbilical Vein Endothelial Cells (HUVECs) stimulated with IgG from APS patients and β2GPI, followed by intersection of RNA-seq data with published microarray and ChIP-seq results (Chromatin Immunoprecipitation). Our strategy revealed that during HUVEC activation diverse signaling pathways such as TNF-α, TGF-β, MAPK38, and Hippo are triggered as indicated by Gene Ontology (GO) classification and pathway analysis. Finally, cell biology approaches performed side-by-side in naïve and stimulated cultured HUVECs, as well as, in placenta specimens derived from Healthy donors (HDs) and APS-patients verified the evolution of an APS-characteristic gene expression program in endothelial cells during the initial stages of the disease's development.
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Affiliation(s)
- Markos Patsouras
- Department of Pathophysiology, Medical School, National and Kapodistrian University of Athens, Greece
| | - Eirini Alexopoulou
- Department of Pathophysiology, Medical School, National and Kapodistrian University of Athens, Greece
| | - Spyros Foutadakis
- Center of Basic Research, Biomedical Research Foundation, Academy of Athens, 4 Soranou Ephessiou Street, Athens, 11527, Greece
| | - Eirini Tsiki
- Department of Pathophysiology, Medical School, National and Kapodistrian University of Athens, Greece
| | - Panagiota Karagianni
- Department of Pathophysiology, Medical School, National and Kapodistrian University of Athens, Greece
| | - Marios Agelopoulos
- Center of Basic Research, Biomedical Research Foundation, Academy of Athens, 4 Soranou Ephessiou Street, Athens, 11527, Greece
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Zogopoulos VL, Malatras A, Kyriakidis K, Charalampous C, Makrygianni EA, Duguez S, Koutsi MA, Pouliou M, Vasileiou C, Duddy WJ, Agelopoulos M, Chrousos GP, Iconomidou VA, Michalopoulos I. HGCA2.0: An RNA-Seq Based Webtool for Gene Coexpression Analysis in Homo sapiens. Cells 2023; 12:cells12030388. [PMID: 36766730 PMCID: PMC9913097 DOI: 10.3390/cells12030388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 01/09/2023] [Accepted: 01/19/2023] [Indexed: 01/24/2023] Open
Abstract
Genes with similar expression patterns in a set of diverse samples may be considered coexpressed. Human Gene Coexpression Analysis 2.0 (HGCA2.0) is a webtool which studies the global coexpression landscape of human genes. The website is based on the hierarchical clustering of 55,431 Homo sapiens genes based on a large-scale coexpression analysis of 3500 GTEx bulk RNA-Seq samples of healthy individuals, which were selected as the best representative samples of each tissue type. HGCA2.0 presents subclades of coexpressed genes to a gene of interest, and performs various built-in gene term enrichment analyses on the coexpressed genes, including gene ontologies, biological pathways, protein families, and diseases, while also being unique in revealing enriched transcription factors driving coexpression. HGCA2.0 has been successful in identifying not only genes with ubiquitous expression patterns, but also tissue-specific genes. Benchmarking showed that HGCA2.0 belongs to the top performing coexpression webtools, as shown by STRING analysis. HGCA2.0 creates working hypotheses for the discovery of gene partners or common biological processes that can be experimentally validated. It offers a simple and intuitive website design and user interface, as well as an API endpoint.
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Affiliation(s)
- Vasileios L. Zogopoulos
- Centre of Systems Biology, Biomedical Research Foundation, Academy of Athens, 11527 Athens, Greece
- Section of Cell Biology and Biophysics, Department of Biology, National and Kapodistrian University of Athens, 15701 Athens, Greece
| | - Apostolos Malatras
- Biobank.cy Center of Excellence in Biobanking and Biomedical Research, University of Cyprus, 2029 Nicosia, Cyprus
| | - Konstantinos Kyriakidis
- Centre of Systems Biology, Biomedical Research Foundation, Academy of Athens, 11527 Athens, Greece
- School of Pharmacy, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - Chrysanthi Charalampous
- Centre of Basic Research, Biomedical Research Foundation, Academy of Athens, 11527 Athens, Greece
| | - Evanthia A. Makrygianni
- University Research Institute of Maternal and Child Health and Precision Medicine, National and Kapodistrian University of Athens, 11527 Athens, Greece
| | - Stéphanie Duguez
- Personalised Medicine Centre, School of Medicine, Ulster University, Derry-Londonderry BT47 6SB, UK
| | - Marianna A. Koutsi
- Centre of Basic Research, Biomedical Research Foundation, Academy of Athens, 11527 Athens, Greece
| | - Marialena Pouliou
- Centre of Basic Research, Biomedical Research Foundation, Academy of Athens, 11527 Athens, Greece
| | - Christos Vasileiou
- Centre of Systems Biology, Biomedical Research Foundation, Academy of Athens, 11527 Athens, Greece
- Engineering Design and Computing Laboratory, ETH Zurich, 8092 Zurich, Switzerland
| | - William J. Duddy
- Personalised Medicine Centre, School of Medicine, Ulster University, Derry-Londonderry BT47 6SB, UK
| | - Marios Agelopoulos
- Centre of Basic Research, Biomedical Research Foundation, Academy of Athens, 11527 Athens, Greece
| | - George P. Chrousos
- University Research Institute of Maternal and Child Health and Precision Medicine, National and Kapodistrian University of Athens, 11527 Athens, Greece
| | - Vassiliki A. Iconomidou
- Section of Cell Biology and Biophysics, Department of Biology, National and Kapodistrian University of Athens, 15701 Athens, Greece
| | - Ioannis Michalopoulos
- Centre of Systems Biology, Biomedical Research Foundation, Academy of Athens, 11527 Athens, Greece
- Correspondence:
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Kalogirou EM, Foutadakis S, Koutsi MA, Vatsellas G, Vlachodimitropoulos D, Petsinis V, Sklavounou A, Agelopoulos M, Tosios KI. Decoding a gene expression program that accompanies the phenotype of sporadic and Basal Cell Nevus Syndrome-associated odontogenic keratocyst. J Oral Pathol Med 2022; 51:649-658. [PMID: 35665542 DOI: 10.1111/jop.13325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 02/28/2022] [Accepted: 03/15/2022] [Indexed: 11/27/2022]
Abstract
BACKGROUND Odontogenic keratocyst (OKC) is characterized by local aggressive behavior and a high recurrence rate, as well as the potential to develop in association with the Basal Cell Nevus Syndrome (BCNS). The aim of this study was to decode the gene expression program accompanying OKC phenotype. METHODS 150-bp paired-end RNA-sequencing was applied on 6 sporadic and 6 BSCN-associated whole-tissue OKC samples in comparison to 6 dental follicles, coupled to bioinformatics and complemented by immunohistochemistry. RESULTS 2,654 and 2,427 differentially expressed genes were captured to characterize the transcriptome of sporadic and BCNS-associated OKCs, respectively. Gene ontologies (GOs) related to "epidermis/skin development" and "keratinocyte/epidermal cell differentiation" were enriched among the upregulated genes (KRT10, NCCRP1, TP63, GRHL3, SOX21), while "extracellular matrix (ECM) organization" (ITGA5, LOXL2) and "odontogenesis" (MSX1, LHX8) GOs were overrepresented among the downregulated genes in OKC. Interestingly, upregulation of various embryonic stem cells (ESCs) markers (EPHA1, SCNN1A) and genes committed in cellular reprogramming (SOX2, KLF4, OVOL1, IRF6, TACSTD2, CDH1) was found in OKC. These findings were highly shared between sporadic and BCNS-associated OKCs. Immunohistochemistry verified SOX2, KLF4, OVOL1, IRF6, TACSTD2/TROP2, CDH1/E-cadherin, and p63 expression predominantly in the OKC suprabasal epithelial layers. CONCLUSION The OKC transcriptomic profile is characterized by a prominent epidermal and dental epithelial fate, a repressed dental mesenchyme fate combined with deregulated ECM organization, and enhanced stemness gene signatures. Thus, we propose a developed epidermis-like phenotype in the OKC suprabasal epithelial cells, established in parallel to a significant upregulation of marker genes related to ESCs and cellular reprogramming. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Eleni-Marina Kalogirou
- Department of Oral Medicine & Pathology and Hospital Dentistry, School of Dentistry, National and Kapodistrian University of Athens, Athens, Greece
| | - Spyros Foutadakis
- Center of Basic Research, Biomedical Research Foundation, Academy of Athens, Athens, Greece
| | - Marianna A Koutsi
- Center of Basic Research, Biomedical Research Foundation, Academy of Athens, Athens, Greece
| | - Giannis Vatsellas
- Center of Basic Research, Biomedical Research Foundation, Academy of Athens, Athens, Greece
| | | | - Vassilis Petsinis
- Department of Oral and Maxillofacial Surgery, School of Dentistry, National and Kapodistrian University of Athens, Athens, Greece
| | - Alexandra Sklavounou
- Department of Oral Medicine & Pathology and Hospital Dentistry, School of Dentistry, National and Kapodistrian University of Athens, Athens, Greece
| | - Marios Agelopoulos
- Center of Basic Research, Biomedical Research Foundation, Academy of Athens, Athens, Greece
| | - Konstantinos I Tosios
- Department of Oral Medicine & Pathology and Hospital Dentistry, School of Dentistry, National and Kapodistrian University of Athens, Athens, Greece
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Kalogirou EM, Foutadakis S, Sklavounou A, Petsinis V, Nikitakis NG, Agelopoulos M, Tosios KI. DECODING THE GENE EXPRESSION PROGRAM EVOLVED IN ODONTOGENIC KERATOCYST BY THE COMBINATION OF DEEP TRANSCRIPTOMICS ANALYSES AND COMPUTATIONAL BIOLOGY TOOLS. Oral Surg Oral Med Oral Pathol Oral Radiol 2021. [DOI: 10.1016/j.oooo.2021.03.094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Agelopoulos M, Foutadakis S, Thanos D. The Causes and Consequences of Spatial Organization of the Genome in Regulation of Gene Expression. Front Immunol 2021; 12:682397. [PMID: 34149720 PMCID: PMC8212036 DOI: 10.3389/fimmu.2021.682397] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Accepted: 05/18/2021] [Indexed: 01/05/2023] Open
Abstract
Regulation of gene expression in time, space and quantity is orchestrated by the functional interplay of cis-acting elements and trans-acting factors. Our current view postulates that transcription factors recognize enhancer DNA and read the transcriptional regulatory code by cooperative DNA binding to specific DNA motifs, thus instructing the recruitment of transcriptional regulatory complexes forming a plethora of higher-ordered multi-protein-DNA and protein-protein complexes. Here, we reviewed the formation of multi-dimensional chromatin assemblies implicated in gene expression with emphasis on the regulatory role of enhancer hubs as coordinators of stochastic gene expression. Enhancer hubs contain many interacting regulatory elements and represent a remarkably dynamic and heterogeneous network of multivalent interactions. A functional consequence of such complex interaction networks could be that individual enhancers function synergistically to ensure coordination, tight control and robustness in regulation of expression of spatially connected genes. In this review, we discuss fundamental paradigms of such inter- and intra- chromosomal associations both in the context of immune-related genes and beyond.
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Affiliation(s)
| | | | - Dimitris Thanos
- Biomedical Research Foundation, Academy of Athens, Athens, Greece
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Papathanasiou M, Tsiftsoglou SA, Polyzos AP, Papadopoulou D, Valakos D, Klagkou E, Karagianni P, Pliatska M, Talianidis I, Agelopoulos M, Thanos D. Identification of a dynamic gene regulatory network required for pluripotency factor-induced reprogramming of mouse fibroblasts and hepatocytes. EMBO J 2021; 40:e102236. [PMID: 33034061 PMCID: PMC7780151 DOI: 10.15252/embj.2019102236] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Revised: 08/27/2020] [Accepted: 09/07/2020] [Indexed: 01/04/2023] Open
Abstract
The generation of induced pluripotent stem cells (iPSCs) from somatic cells provides an excellent model to study mechanisms of transcription factor-induced global alterations of the epigenome and genome function. Here, we have investigated the early transcriptional events of cellular reprogramming triggered by the co-expression of Oct4, Sox2, Klf4, and c-Myc (OSKM) in mouse embryonic fibroblasts (MEFs) and mouse hepatocytes (mHeps). In this analysis, we identified a gene regulatory network composed of nine transcriptional regulators (9TR; Cbfa2t3, Gli2, Irf6, Nanog, Ovol1, Rcan1, Taf1c, Tead4, and Tfap4), which are directly targeted by OSKM, in vivo. Functional studies using single and double shRNA knockdowns of any of these factors caused disruption of the network and dramatic reductions in reprogramming efficiency, indicating that this network is essential for the induction and establishment of pluripotency. We demonstrate that the stochastic co-expression of 9TR network components occurs in a remarkably small number of cells, approximating the percentage of terminally reprogrammed cells as a result of dynamic molecular events. Thus, the early DNA-binding patterns of OSKM and the subsequent probabilistic co-expression of essential 9TR components in subpopulations of cells undergoing reprogramming steer the reconstruction of a gene regulatory network marking the transition to pluripotency.
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Affiliation(s)
| | | | | | | | | | | | | | - Maria Pliatska
- Biomedical Research Foundation Academy of AthensAthensGreece
| | | | | | - Dimitris Thanos
- Biomedical Research Foundation Academy of AthensAthensGreece
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Panagoulias I, Georgakopoulos T, Aggeletopoulou I, Agelopoulos M, Thanos D, Mouzaki A. Transcription Factor Ets-2 Acts as a Preinduction Repressor of Interleukin-2 (IL-2) Transcription in Naive T Helper Lymphocytes. J Biol Chem 2016; 291:26707-26721. [PMID: 27815505 DOI: 10.1074/jbc.m116.762179] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Revised: 11/01/2016] [Indexed: 11/06/2022] Open
Abstract
IL-2 is the first cytokine produced when naive T helper (Th) cells are activated and differentiate into dividing pre-Th0 proliferating precursors. IL-2 expression is blocked in naive, but not activated or memory, Th cells by the transcription factor Ets-2 that binds to the antigen receptor response element (ARRE)-2 of the proximal IL-2 promoter. Ets-2 acts as an independent preinduction repressor in naive Th cells and does not interact physically with the transcription factor NFAT (nuclear factor of activated T-cells) that binds to the ARRE-2 in activated Th cells. In naive Th cells, Ets-2 mRNA expression, Ets-2 protein levels, and Ets-2 binding to ARRE-2 decrease upon cell activation followed by the concomitant expression of IL-2. Cyclosporine A stabilizes Ets-2 mRNA and protein when the cells are activated. Ets-2 silences directly constitutive or induced IL-2 expression through the ARRE-2. Conversely, Ets-2 silencing allows for constitutive IL-2 expression in unstimulated cells. Ets-2 binding to ARRE-2 in chromatin is stronger in naive compared with activated or memory Th cells; in the latter, Ets-2 participates in a change of the IL-2 promoter architecture, possibly to facilitate a quick response when the cells re-encounter antigen. We propose that Ets-2 expression and protein binding to the ARRE-2 of the IL-2 promoter are part of a strictly regulated process that results in a physiological transition of naive Th cells to Th0 cells upon antigenic stimulation. Malfunction of such a repression mechanism at the molecular level could lead to a disturbance of later events in Th cell plasticity, leading to autoimmune diseases or other pathological conditions.
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Affiliation(s)
- Ioannis Panagoulias
- From the Division of Hematology, Department of Internal Medicine, Faculty of Medicine, University of Patras, Patras GR-26500, Greece and
| | - Tassos Georgakopoulos
- From the Division of Hematology, Department of Internal Medicine, Faculty of Medicine, University of Patras, Patras GR-26500, Greece and
| | - Ioanna Aggeletopoulou
- From the Division of Hematology, Department of Internal Medicine, Faculty of Medicine, University of Patras, Patras GR-26500, Greece and
| | - Marios Agelopoulos
- the Institute of Molecular Biology, Genetics and Biotechnology, Biomedical Research Foundation, Academy of Athens, Athens GR-11527, Greece
| | - Dimitris Thanos
- the Institute of Molecular Biology, Genetics and Biotechnology, Biomedical Research Foundation, Academy of Athens, Athens GR-11527, Greece
| | - Athanasia Mouzaki
- From the Division of Hematology, Department of Internal Medicine, Faculty of Medicine, University of Patras, Patras GR-26500, Greece and
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Abstract
Many coregulated genes assemble in multigene complexes via stochastic inter- and intrachromosomal interactions. In this issue, Fanucchi et al. report that chromatin loop formation governs hierarchical cotranscription within a multigene complex.
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Affiliation(s)
- Aggelos Banos
- Biomedical Research Foundation, Academy of Athens, 4 Soranou Efesiou Street, Athens 11527, Greece
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Agelopoulos M, Thanos D. Epigenetic determination of a cell-specific gene expression program by ATF-2 and the histone variant macroH2A. EMBO J 2006; 25:4843-53. [PMID: 17036053 PMCID: PMC1618095 DOI: 10.1038/sj.emboj.7601364] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2006] [Accepted: 08/31/2006] [Indexed: 02/03/2023] Open
Abstract
Transcriptional activation of the interleukin-8 (IL-8) gene is restricted to distinct cell types, although the transcriptional regulatory proteins controlling IL-8 gene expression are ubiquitous. We show that cell-specific transcription of IL-8 is due to the distinct chromatin architecture on the enhancer/promoter before the arrival of the inducing signal. In expressing epithelial cells the enhancer/promoter is nucleosome-free, whereas in non-expressing B cells a nucleosome masks the entire regulatory region. The B-cell-specific nucleosome contains the histone variant macroH2A, which is responsible for preventing transcription factor binding. Recruitment of the repressive macroH2A nucleosome requires direct interactions between ATF-2 bound to the nearby AP1 site and macroH2A and it is regulated by DNA-induced protein allostery. siRNA against ATF-2 or macroH2A rescues IL-8 transcription in B cells. Thus, a transcription factor can work as a transcriptional repressor by orchestrating and maintaining the assembly of specialized local chromatin architectures.
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Affiliation(s)
- Marios Agelopoulos
- Institute of Molecular Biology and Genetics, Biomedical Sciences Research Center ‘Al. Fleming', Vari, Athens, Greece
| | - Dimitris Thanos
- Institute of Molecular Biology and Genetics, Biomedical Sciences Research Center ‘Al. Fleming', Vari, Athens, Greece
- Present address: Institute of Molecular Biology, Genetics and Biotechnology, Foundation for Biomedical Research of the Academy of Athens, 4 Soranou Efesiou Street, Athens 11527, Greece. Tel.: +30 210 6597244; Fax: +30 210 6597545; E-mail: or
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