1
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Coatti GC, Vaghela N, Gillurkar P, Leir SH, Harris A. A promoter-dependent upstream activator augments CFTR expression in diverse epithelial cell types. BIOCHIMICA ET BIOPHYSICA ACTA. GENE REGULATORY MECHANISMS 2024; 1867:195031. [PMID: 38679287 DOI: 10.1016/j.bbagrm.2024.195031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2024] [Revised: 04/22/2024] [Accepted: 04/23/2024] [Indexed: 05/01/2024]
Abstract
The cystic fibrosis transmembrane conductance regulator (CFTR) gene encodes an anion-selective channel found in epithelial cell membranes. Mutations in CFTR cause cystic fibrosis (CF), an inherited disorder that impairs epithelial function in multiple organs. Most men with CF are infertile due to loss of intact genital ducts. Here we investigated a novel epididymis-selective cis-regulatory element (CRE), located within a peak of open chromatin at -9.5 kb 5' to the CFTR gene promoter. Activation of the -9.5 kb CRE alone by CRISPRa had no impact on CFTR gene expression. However, CRISPRa co-activation of the -9.5 kb CRE and the CFTR gene promoter in epididymis cells significantly augmented CFTR mRNA and protein expression when compared to promoter activation alone. This increase was accompanied by enhanced chromatin accessibility at both sites. Furthermore, the combined CRISPRa strategy activated CFTR expression in other epithelial cells that lack open chromatin at the -9.5 kb site and in which the locus is normally inactive. However, the -9.5 kb CRE does not function as a classical enhancer of the CFTR promoter in transient reporter gene assays. These data provide a novel mechanism for activating/augmenting CFTR expression, which may have therapeutic utility for mutations that perturb CFTR transcription.
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Affiliation(s)
- Giuliana C Coatti
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Nirbhayaditya Vaghela
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Pulak Gillurkar
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Shih-Hsing Leir
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Ann Harris
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA.
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2
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Lee KH, Kim J, Kim JH. 3D epigenomics and 3D epigenopathies. BMB Rep 2024; 57:216-231. [PMID: 38627948 PMCID: PMC11139681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 01/15/2024] [Accepted: 03/18/2024] [Indexed: 05/25/2024] Open
Abstract
Mammalian genomes are intricately compacted to form sophisticated 3-dimensional structures within the tiny nucleus, so called 3D genome folding. Despite their shapes reminiscent of an entangled yarn, the rapid development of molecular and next-generation sequencing technologies (NGS) has revealed that mammalian genomes are highly organized in a hierarchical order that delicately affects transcription activities. An increasing amount of evidence suggests that 3D genome folding is implicated in diseases, giving us a clue on how to identify novel therapeutic approaches. In this review, we will study what 3D genome folding means in epigenetics, what types of 3D genome structures there are, how they are formed, and how the technologies have developed to explore them. We will also discuss the pathological implications of 3D genome folding. Finally, we will discuss how to leverage 3D genome folding and engineering for future studies. [BMB Reports 2024; 57(5): 216-231].
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Affiliation(s)
- Kyung-Hwan Lee
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea
| | - Jungyu Kim
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea
| | - Ji Hun Kim
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea
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3
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Kocanova S, Raynal F, Goiffon I, Oksuz BA, Baú D, Kamgoué A, Cantaloube S, Zhan Y, Lajoie B, Marti-Renom MA, Dekker J, Bystricky K. Enhancer-driven 3D chromatin domain folding modulates transcription in human mammary tumor cells. Life Sci Alliance 2024; 7:e202302154. [PMID: 37989525 PMCID: PMC10663337 DOI: 10.26508/lsa.202302154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Revised: 11/03/2023] [Accepted: 11/06/2023] [Indexed: 11/23/2023] Open
Abstract
The genome is organized in functional compartments and structural domains at the sub-megabase scale. How within these domains interactions between numerous cis-acting enhancers and promoters regulate transcription remains an open question. Here, we determined chromatin folding and composition over several hundred kb around estrogen-responsive genes in human breast cancer cell lines after hormone stimulation. Modeling of 5C data at 1.8 kb resolution was combined with quantitative 3D analysis of multicolor FISH measurements at 100 nm resolution and integrated with ChIP-seq data on transcription factor binding and histone modifications. We found that rapid estradiol induction of the progesterone gene expression occurs in the context of preexisting, cell type-specific chromosomal architectures encompassing the 90 kb progesterone gene coding region and an enhancer-spiked 5' 300 kb upstream genomic region. In response to estradiol, interactions between estrogen receptor α (ERα) bound regulatory elements are reinforced. Whereas initial enhancer-gene contacts coincide with RNA Pol 2 binding and transcription initiation, sustained hormone stimulation promotes ERα accumulation creating a regulatory hub stimulating transcript synthesis. In addition to implications for estrogen receptor signaling, we uncover that preestablished chromatin architectures efficiently regulate gene expression upon stimulation without the need for de novo extensive rewiring of long-range chromatin interactions.
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Affiliation(s)
- Silvia Kocanova
- Molecular, Cellular and Developmental Biology Unit (MCD), Centre de Biologie Integrative (CBI), University of Toulouse, UPS, CNRS, Toulouse, France
| | - Flavien Raynal
- Molecular, Cellular and Developmental Biology Unit (MCD), Centre de Biologie Integrative (CBI), University of Toulouse, UPS, CNRS, Toulouse, France
| | - Isabelle Goiffon
- Molecular, Cellular and Developmental Biology Unit (MCD), Centre de Biologie Integrative (CBI), University of Toulouse, UPS, CNRS, Toulouse, France
| | - Betul Akgol Oksuz
- https://ror.org/0464eyp60 Department of Systems Biology, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Davide Baú
- Centre Nacional d'Anàlisi Genòmica (CNAG), Barcelona, Spain
| | - Alain Kamgoué
- Molecular, Cellular and Developmental Biology Unit (MCD), Centre de Biologie Integrative (CBI), University of Toulouse, UPS, CNRS, Toulouse, France
| | - Sylvain Cantaloube
- Molecular, Cellular and Developmental Biology Unit (MCD), Centre de Biologie Integrative (CBI), University of Toulouse, UPS, CNRS, Toulouse, France
| | - Ye Zhan
- https://ror.org/0464eyp60 Department of Systems Biology, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Bryan Lajoie
- https://ror.org/0464eyp60 Department of Systems Biology, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Marc A Marti-Renom
- Centre Nacional d'Anàlisi Genòmica (CNAG), Barcelona, Spain
- Genome Biology Program, Centre de Regulació Genòmica (CRG), Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
| | - Job Dekker
- https://ror.org/0464eyp60 Department of Systems Biology, University of Massachusetts Chan Medical School, Worcester, MA, USA
- Howard Hughes Medical Institute, Chevy Chase, MD, USA
| | - Kerstin Bystricky
- Molecular, Cellular and Developmental Biology Unit (MCD), Centre de Biologie Integrative (CBI), University of Toulouse, UPS, CNRS, Toulouse, France
- Institut Universitaire de France (IUF), Paris, France
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4
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Wang MY, Zhang CM, Zhou HH, Ge ZB, Su CC, Lou ZH, Zhang XY, Xu TT, Li SY, Zhu L, Zhou YL, Wu Y, Ji SR. Identification of a distal enhancer that determines the expression pattern of acute phase marker C-reactive protein. J Biol Chem 2022; 298:102160. [PMID: 35724961 PMCID: PMC9287136 DOI: 10.1016/j.jbc.2022.102160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Revised: 06/09/2022] [Accepted: 06/11/2022] [Indexed: 11/18/2022] Open
Abstract
C-reactive protein (CRP) is a major acute phase protein and inflammatory marker, the expression of which is largely liver specific and highly inducible. Enhancers are regulatory elements critical for the precise activation of gene expression, yet the contributions of enhancers to the expression pattern of CRP have not been well defined. Here, we identify a constitutively active enhancer (E1) located 37.7 kb upstream of the promoter of human CRP in hepatocytes. By using chromatin immunoprecipitation, luciferase reporter assay, in situ genetic manipulation, CRISPRi, and CRISPRa, we show that E1 is enriched in binding sites for transcription factors STAT3 and C/EBP-β and is essential for the full induction of human CRP during the acute phase. Moreover, we demonstrate that E1 orchestrates with the promoter of CRP to determine its varied expression across tissues and species through surveying activities of E1-promoter hybrids and the associated epigenetic modifications. These results thus suggest an intriguing mode of molecular evolution wherein expression-changing mutations in distal regulatory elements initiate subsequent functional selection involving coupling among distal/proximal regulatory mutations and activity-changing coding mutations.
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Affiliation(s)
- Ming-Yu Wang
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, P.R. China
| | - Chun-Miao Zhang
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, P.R. China
| | - Hai-Hong Zhou
- Gansu Provincial Cancer Hospital, Lanzhou 730050, P.R. China
| | - Zhong-Bo Ge
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, P.R. China
| | - Chen-Chen Su
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, P.R. China
| | - Zi-Hao Lou
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, P.R. China
| | - Xin-Yun Zhang
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, P.R. China
| | - Tao-Tao Xu
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, P.R. China
| | - Si-Yi Li
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, P.R. China
| | - Li Zhu
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, P.R. China; Electron Microscopy Centre of Lanzhou University, Lanzhou 730000, China
| | - Ya-Li Zhou
- Cuiying Biomedical Research Center, Lanzhou University Second Hospital, Lanzhou, 730030, China
| | - Yi Wu
- MOE Key Laboratory of Environment and Genes Related to Diseases, School of Basic Medical Sciences, Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China; Key Laboratory of Precision Medicine to Pediatric Diseases of Shaanxi Province, Xi'an Children's Hospital, Xi'an Jiaotong University, Xi'an, P.R. China.
| | - Shang-Rong Ji
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, P.R. China.
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5
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Boldyreva LV, Andreyeva EN, Pindyurin AV. Position Effect Variegation: Role of the Local Chromatin Context in Gene Expression Regulation. Mol Biol 2022. [DOI: 10.1134/s0026893322030049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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6
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Yin S, Mazumdar MN, Paranjapye A, Harris A. Cross-talk between enhancers, structural elements and activating transcription factors maintains the 3D architecture and expression of the CFTR gene. Genomics 2022; 114:110350. [PMID: 35346781 PMCID: PMC9509493 DOI: 10.1016/j.ygeno.2022.110350] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 03/13/2022] [Accepted: 03/23/2022] [Indexed: 01/14/2023]
Abstract
Robust protocols to examine 3D chromatin structure have greatly advanced knowledge of gene regulatory mechanisms. Here we focus on the cystic fibrosis transmembrane conductance regulator (CFTR) gene, which provides a paradigm for validating models of gene regulation built upon genome-wide analysis. We examine the mechanisms by which multiple cis-regulatory elements (CREs) at the CFTR gene coordinate its expression in intestinal epithelial cells. Using CRISPR/Cas9 to remove CREs, individually and in tandem, followed by assays of gene expression and higher-order chromatin structure (4C-seq), we reveal the cross-talk and dependency of two cell-specific intronic enhancers. The results suggest a mechanism whereby the locus responds when CREs are lost, which may involve activating transcription factors such as FOXA2. Also, by removing the 5' topologically-associating domain (TAD) boundary, we illustrate its impact on CFTR gene expression and architecture. These data suggest a multi-layered regulatory hierarchy that is highly sensitive to perturbations.
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7
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Paranjapye A, NandyMazumdar M, Harris A. Krüppel-Like Factor 5 Regulates CFTR Expression Through Repression by Maintaining Chromatin Architecture Coupled with Direct Enhancer Activation. J Mol Biol 2022; 434:167561. [PMID: 35341742 DOI: 10.1016/j.jmb.2022.167561] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Revised: 03/18/2022] [Accepted: 03/21/2022] [Indexed: 02/06/2023]
Abstract
Single cell RNA-sequencing has accurately identified cell types within the human airway that express the Cystic Fibrosis Transmembrane Conductance regulator (CFTR) gene. Low abundance CFTR transcripts are seen in many secretory cells, while high levels are restricted to rare pulmonary ionocytes. Here we focus on the mechanisms coordinating basal CFTR expression in the secretory compartment. Cell-selective regulation of CFTR is achieved within its invariant topologically associating domain by the recruitment of cis-regulatory elements (CREs). CRE activity is coordinated by cell-type-selective transcription factors. One such factor, Krüppel-Like Factor 5 (KLF5), profoundly represses CFTR transcript and protein in primary human airway epithelial cells and airway cell lines. Here we reveal the mechanism of action of KLF5 upon the CFTR gene. We find that depletion or ablation of KLF5 from airway epithelial cells changes higher order chromatin structure at the CFTR locus. Critical looping interactions that are required for normal gene expression are altered, the H3K27ac active chromatin mark is redistributed, and CTCF occupancy is modified. However, mutation of a single KLF5 binding site within a pivotal airway cell CRE abolishes CFTR expression. Hence, KLF5 has both direct activating and indirect repressive effects, which together coordinate CFTR expression in the airway.
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Affiliation(s)
- Alekh Paranjapye
- Department of Genetics and Genome Sciences, and Case Comprehensive Cancer Center, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Monali NandyMazumdar
- Department of Genetics and Genome Sciences, and Case Comprehensive Cancer Center, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Ann Harris
- Department of Genetics and Genome Sciences, and Case Comprehensive Cancer Center, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA.
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8
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Gokuladhas S, Zaied RE, Schierding W, Farrow S, Fadason T, O'Sullivan JM. Integrating Multimorbidity into a Whole-Body Understanding of Disease Using Spatial Genomics. Results Probl Cell Differ 2022; 70:157-187. [PMID: 36348107 DOI: 10.1007/978-3-031-06573-6_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Multimorbidity is characterized by multidimensional complexity emerging from interactions between multiple diseases across levels of biological (including genetic) and environmental determinants and the complex array of interactions between and within cells, tissues and organ systems. Advances in spatial genomic research have led to an unprecedented expansion in our ability to link alterations in genome folding with changes that are associated with human disease. Studying disease-associated genetic variants in the context of the spatial genome has enabled the discovery of transcriptional regulatory programmes that potentially link dysregulated genes to disease development. However, the approaches that have been used have typically been applied to uncover pathological molecular mechanisms occurring in a specific disease-relevant tissue. These forms of reductionist, targeted investigations are not appropriate for the molecular dissection of multimorbidity that typically involves contributions from multiple tissues. In this perspective, we emphasize the importance of a whole-body understanding of multimorbidity and discuss how spatial genomics, when integrated with additional omic datasets, could provide novel insights into the molecular underpinnings of multimorbidity.
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Affiliation(s)
| | - Roan E Zaied
- Liggins Institute, The University of Auckland, Auckland, New Zealand
| | - William Schierding
- Liggins Institute, The University of Auckland, Auckland, New Zealand
- The Maurice Wilkins Centre, The University of Auckland, Auckland, New Zealand
| | - Sophie Farrow
- Liggins Institute, The University of Auckland, Auckland, New Zealand
| | - Tayaza Fadason
- Liggins Institute, The University of Auckland, Auckland, New Zealand
- The Maurice Wilkins Centre, The University of Auckland, Auckland, New Zealand
| | - Justin M O'Sullivan
- Liggins Institute, The University of Auckland, Auckland, New Zealand.
- The Maurice Wilkins Centre, The University of Auckland, Auckland, New Zealand.
- Australian Parkinson's Mission, Garvan Institute of Medical Research, Sydney, NSW, Australia.
- MRC Lifecourse Epidemiology Unit, University of Southampton, Southampton, UK.
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9
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Fritz AJ, El Dika M, Toor RH, Rodriguez PD, Foley SJ, Ullah R, Nie D, Banerjee B, Lohese D, Glass KC, Frietze S, Ghule PN, Heath JL, Imbalzano AN, van Wijnen A, Gordon J, Lian JB, Stein JL, Stein GS, Stein GS. Epigenetic-Mediated Regulation of Gene Expression for Biological Control and Cancer: Cell and Tissue Structure, Function, and Phenotype. Results Probl Cell Differ 2022; 70:339-373. [PMID: 36348114 PMCID: PMC9753575 DOI: 10.1007/978-3-031-06573-6_12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Epigenetic gene regulatory mechanisms play a central role in the biological control of cell and tissue structure, function, and phenotype. Identification of epigenetic dysregulation in cancer provides mechanistic into tumor initiation and progression and may prove valuable for a variety of clinical applications. We present an overview of epigenetically driven mechanisms that are obligatory for physiological regulation and parameters of epigenetic control that are modified in tumor cells. The interrelationship between nuclear structure and function is not mutually exclusive but synergistic. We explore concepts influencing the maintenance of chromatin structures, including phase separation, recognition signals, factors that mediate enhancer-promoter looping, and insulation and how these are altered during the cell cycle and in cancer. Understanding how these processes are altered in cancer provides a potential for advancing capabilities for the diagnosis and identification of novel therapeutic targets.
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Affiliation(s)
- Andrew J. Fritz
- University of Vermont, UVM Cancer Center, Larner College of Medicine, Department of Biochemistry, Burlington, VT 05405
| | - Mohammed El Dika
- University of Vermont, UVM Cancer Center, Larner College of Medicine, Department of Biochemistry, Burlington, VT 05405
| | - Rabail H. Toor
- University of Vermont, UVM Cancer Center, Larner College of Medicine, Department of Biochemistry, Burlington, VT 05405
| | | | - Stephen J. Foley
- University of Vermont, UVM Cancer Center, Larner College of Medicine, Department of Biochemistry, Burlington, VT 05405
| | - Rahim Ullah
- University of Vermont, UVM Cancer Center, Larner College of Medicine, Department of Biochemistry, Burlington, VT 05405
| | - Daijing Nie
- University of Vermont, UVM Cancer Center, Larner College of Medicine, Department of Biochemistry, Burlington, VT 05405
| | - Bodhisattwa Banerjee
- University of Vermont, UVM Cancer Center, Larner College of Medicine, Department of Biochemistry, Burlington, VT 05405
| | - Dorcas Lohese
- University of Vermont, UVM Cancer Center, Larner College of Medicine, Department of Biochemistry, Burlington, VT 05405
| | - Karen C. Glass
- University of Vermont, UVM Cancer Center, Larner College of Medicine, Department of Pharmacology, Burlington, VT 05405
| | - Seth Frietze
- University of Vermont, College of Nursing and Health Sciences, Burlington, VT 05405
| | - Prachi N. Ghule
- University of Vermont, UVM Cancer Center, Larner College of Medicine, Department of Biochemistry, Burlington, VT 05405
| | - Jessica L. Heath
- University of Vermont, UVM Cancer Center, Larner College of Medicine, Department of Biochemistry, Burlington, VT 05405,University of Vermont, Larner College of Medicine, Department of Pediatrics, Burlington, VT 05405
| | - Anthony N. Imbalzano
- UMass Chan Medical School, Department of Biochemistry and Molecular Biotechnology, Worcester, MA 01605
| | - Andre van Wijnen
- University of Vermont, UVM Cancer Center, Larner College of Medicine, Department of Biochemistry, Burlington, VT 05405
| | - Jonathan Gordon
- University of Vermont, UVM Cancer Center, Larner College of Medicine, Department of Biochemistry, Burlington, VT 05405
| | - Jane B. Lian
- University of Vermont, UVM Cancer Center, Larner College of Medicine, Department of Biochemistry, Burlington, VT 05405
| | - Janet L. Stein
- University of Vermont, UVM Cancer Center, Larner College of Medicine, Department of Biochemistry, Burlington, VT 05405
| | - Gary S. Stein
- University of Vermont, UVM Cancer Center, Larner College of Medicine, Department of Biochemistry, Burlington, VT 05405
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10
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Park YJ, Han SM, Huh JY, Kim JB. Emerging roles of epigenetic regulation in obesity and metabolic disease. J Biol Chem 2021; 297:101296. [PMID: 34637788 PMCID: PMC8561000 DOI: 10.1016/j.jbc.2021.101296] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 10/07/2021] [Accepted: 10/07/2021] [Indexed: 01/10/2023] Open
Abstract
Adipose tissue dysfunction is a hallmark of obesity and contributes to obesity-related sequelae such as metabolic complications and insulin resistance. Compelling evidence indicates that adipose-tissue-specific gene expression is influenced by gene interactions with proximal and distal cis-regulatory elements; the latter exert regulatory effects via three-dimensional (3D) chromosome conformation. Recent advances in determining the regulatory mechanisms reveal that compromised epigenomes are molecularly interlinked to altered cis-regulatory element activity and chromosome architecture in the adipose tissue. This review summarizes the roles of epigenomic components, particularly DNA methylation, in transcriptional rewiring in adipose tissue. In addition, we discuss the emerging roles of DNA methylation in the maintenance of 3D chromosome conformation and its pathophysiological significance concerning adipose tissue function.
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Affiliation(s)
- Yoon Jeong Park
- Center for Adipose Tissue Remodeling, Institute of Molecular Biology and Genetics, School of Biological Sciences, Seoul National University, Seoul, South Korea
| | - Sang Mun Han
- Center for Adipose Tissue Remodeling, Institute of Molecular Biology and Genetics, School of Biological Sciences, Seoul National University, Seoul, South Korea
| | - Jin Young Huh
- Center for Adipose Tissue Remodeling, Institute of Molecular Biology and Genetics, School of Biological Sciences, Seoul National University, Seoul, South Korea
| | - Jae Bum Kim
- Center for Adipose Tissue Remodeling, Institute of Molecular Biology and Genetics, School of Biological Sciences, Seoul National University, Seoul, South Korea.
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11
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Collobert M, Bocher O, Le Nabec A, Génin E, Férec C, Moisan S. CFTR Cooperative Cis-Regulatory Elements in Intestinal Cells. Int J Mol Sci 2021; 22:ijms22052599. [PMID: 33807548 PMCID: PMC7961337 DOI: 10.3390/ijms22052599] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 02/25/2021] [Accepted: 02/27/2021] [Indexed: 11/16/2022] Open
Abstract
About 8% of the human genome is covered with candidate cis-regulatory elements (cCREs). Disruptions of CREs, described as "cis-ruptions" have been identified as being involved in various genetic diseases. Thanks to the development of chromatin conformation study techniques, several long-range cystic fibrosis transmembrane conductance regulator (CFTR) regulatory elements were identified, but the regulatory mechanisms of the CFTR gene have yet to be fully elucidated. The aim of this work is to improve our knowledge of the CFTR gene regulation, and to identity factors that could impact the CFTR gene expression, and potentially account for the variability of the clinical presentation of cystic fibrosis as well as CFTR-related disorders. Here, we apply the robust GWAS3D score to determine which of the CFTR introns could be involved in gene regulation. This approach highlights four particular CFTR introns of interest. Using reporter gene constructs in intestinal cells, we show that two new introns display strong cooperative effects in intestinal cells. Chromatin immunoprecipitation analyses further demonstrate fixation of transcription factors network. These results provide new insights into our understanding of the CFTR gene regulation and allow us to suggest a 3D CFTR locus structure in intestinal cells. A better understand of regulation mechanisms of the CFTR gene could elucidate cases of patients where the phenotype is not yet explained by the genotype. This would thus help in better diagnosis and therefore better management. These cis-acting regions may be a therapeutic challenge that could lead to the development of specific molecules capable of modulating gene expression in the future.
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Affiliation(s)
- Mégane Collobert
- Univ. Brest, Inserm, EFS, UMR 1078, GGB, F-29200 Brest, France; (O.B.); (A.L.N.); (E.G.); (C.F.)
- Correspondence: (M.C.); (S.M.); Tel.: +33-298-0165-67 (M.C.)
| | - Ozvan Bocher
- Univ. Brest, Inserm, EFS, UMR 1078, GGB, F-29200 Brest, France; (O.B.); (A.L.N.); (E.G.); (C.F.)
| | - Anaïs Le Nabec
- Univ. Brest, Inserm, EFS, UMR 1078, GGB, F-29200 Brest, France; (O.B.); (A.L.N.); (E.G.); (C.F.)
| | - Emmanuelle Génin
- Univ. Brest, Inserm, EFS, UMR 1078, GGB, F-29200 Brest, France; (O.B.); (A.L.N.); (E.G.); (C.F.)
| | - Claude Férec
- Univ. Brest, Inserm, EFS, UMR 1078, GGB, F-29200 Brest, France; (O.B.); (A.L.N.); (E.G.); (C.F.)
- Department of Molecular Genetics and Reproduction Biology, CHRU Brest, F-29200 Brest, France
| | - Stéphanie Moisan
- Univ. Brest, Inserm, EFS, UMR 1078, GGB, F-29200 Brest, France; (O.B.); (A.L.N.); (E.G.); (C.F.)
- Department of Molecular Genetics and Reproduction Biology, CHRU Brest, F-29200 Brest, France
- Correspondence: (M.C.); (S.M.); Tel.: +33-298-0165-67 (M.C.)
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12
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Baietti MF, Zhao P, Crowther J, Sewduth RN, De Troyer L, Debiec-Rychter M, Sablina AA. Loss of 9p21 Regulatory Hub Promotes Kidney Cancer Progression by Upregulating HOXB13. Mol Cancer Res 2021; 19:979-990. [PMID: 33619226 DOI: 10.1158/1541-7786.mcr-20-0705] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 12/24/2020] [Accepted: 02/16/2021] [Indexed: 11/16/2022]
Abstract
Loss of chromosome 9p21 is observed in one-thirds of clear-cell renal cell carcinoma (ccRCC) and is associated with poorer patient survival. Unexpectedly, 9p21 LOH does not lead to decreased expression of the 9p21 tumor suppressor genes, CDKN2A and CDKN2B, suggesting alternative mechanisms of 9p-mediated tumorigenesis. Concordantly, CRISPR-mediated 9p21 deletion promotes growth of immortalized human embryonic kidney epithelial cells independently of the CDKN2A/B pathway inactivation. The 9p21 locus has a highly accessible chromatin structure, suggesting that 9p21 loss might contribute to kidney cancer progression by dysregulating genes distal to the 9p21 locus. We identified several 9p21 regulatory hubs by assessing which of the 9p21-interacting genes are dysregulated in 9p21-deleted kidney cells and ccRCCs. By focusing on the analysis of the homeobox gene 13 (HOXB13) locus, we found that 9p21 loss relieves the HOXB13 locus, decreasing HOXB13 methylation and promoting its expression. Upregulation of HOXB13 facilitates cell growth and is associated with poorer survival of patients with ccRCC. IMPLICATIONS: The results of our study propose a novel tumor suppressive mechanism on the basis of coordinated expression of physically associated genes, providing a better understanding of the role of chromosomal deletions in cancer.
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Affiliation(s)
- Maria Francesca Baietti
- VIB-KU Leuven Center for Cancer Biology, Leuven, Belgium. .,Department of Oncology, KU Leuven, Leuven, Belgium
| | - Peihua Zhao
- VIB-KU Leuven Center for Cancer Biology, Leuven, Belgium.,Department of Oncology, KU Leuven, Leuven, Belgium
| | - Jonathan Crowther
- VIB-KU Leuven Center for Cancer Biology, Leuven, Belgium.,Department of Oncology, KU Leuven, Leuven, Belgium
| | - Raj Nayan Sewduth
- VIB-KU Leuven Center for Cancer Biology, Leuven, Belgium.,Department of Oncology, KU Leuven, Leuven, Belgium
| | - Linde De Troyer
- VIB-KU Leuven Center for Cancer Biology, Leuven, Belgium.,Department of Oncology, KU Leuven, Leuven, Belgium
| | - Maria Debiec-Rychter
- Department of Human Genetics, KU Leuven, Leuven, Belgium.,Department of Pathology, University Hospitals KU Leuven, Leuven, Belgium
| | - Anna A Sablina
- VIB-KU Leuven Center for Cancer Biology, Leuven, Belgium. .,Department of Oncology, KU Leuven, Leuven, Belgium
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13
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Farcas AM, Nagarajan S, Cosulich S, Carroll JS. Genome-Wide Estrogen Receptor Activity in Breast Cancer. Endocrinology 2021; 162:bqaa224. [PMID: 33284960 PMCID: PMC7787425 DOI: 10.1210/endocr/bqaa224] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Indexed: 12/13/2022]
Abstract
The largest subtype of breast cancer is characterized by the expression and activity of the estrogen receptor alpha (ERalpha/ER). Although several effective therapies have significantly improved survival, the adaptability of cancer cells means that patients frequently stop responding or develop resistance to endocrine treatment. ER does not function in isolation and multiple associating factors have been reported to play a role in regulating the estrogen-driven transcriptional program. This review focuses on the dynamic interplay between some of these factors which co-occupy ER-bound regulatory elements, their contribution to estrogen signaling, and their possible therapeutic applications. Furthermore, the review illustrates how some ER association partners can influence and reprogram the genomic distribution of the estrogen receptor. As this dynamic ER activity enables cancer cell adaptability and impacts the clinical outcome, defining how this plasticity is determined is fundamental to our understanding of the mechanisms of disease progression.
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Affiliation(s)
- Anca M Farcas
- Bioscience, Oncology R&D, AstraZeneca, Cambridge, UK
- CRUK Cambridge Institute, University of Cambridge, Cambridge, UK
| | - Sankari Nagarajan
- CRUK Cambridge Institute, University of Cambridge, Cambridge, UK
- Division of Molecular and Cellular Function, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK
| | | | - Jason S Carroll
- CRUK Cambridge Institute, University of Cambridge, Cambridge, UK
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14
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Tomikawa J, Takada S, Okamura K, Terao M, Ogata-Kawata H, Akutsu H, Tanaka S, Hata K, Nakabayashi K. Exploring trophoblast-specific Tead4 enhancers through chromatin conformation capture assays followed by functional screening. Nucleic Acids Res 2020; 48:278-289. [PMID: 31777916 PMCID: PMC6943130 DOI: 10.1093/nar/gkz1034] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 10/17/2019] [Accepted: 11/11/2019] [Indexed: 01/03/2023] Open
Abstract
Tead4 is critical for blastocyst development and trophoblast differentiation. We assayed long-range chromosomal interactions on the Tead4 promoter in mouse embryonic stem (ES) cells and trophoblast stem (TS) cells. Using luciferase reporter assays with ES and TS cells for 34 candidate enhancer regions, we identified five genomic fragments that increased Tead4 promoter activity in a TS-specific manner. The five loci consisted of three intra- and two inter-chromosomal loci relative to Tead4 on chromosome 6. We established five mouse lines with one of the five enhancer elements deleted and evaluated the effect of each deletion on Tead4 expression in blastocysts. By quantitative RT-PCR, we measured a 42% decrease in Tead4 expression in the blastocysts with a homozygous deletion with a 1.5 kb genomic interval on chromosome 19 (n = 14) than in wild-type blastocysts. By conducting RNA-seq analysis, we confirmed the trans effect of this enhancer deletion on Tead4 without significant cis effects on its neighbor genes at least within a 1.7 Mb distance. Our results demonstrated that the genomic interval on chromosome 19 is required for the appropriate level of Tead4 expression in blastocysts and suggested that an inter-chromosomal enhancer-promoter interaction may be the underlying mechanism.
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Affiliation(s)
- Junko Tomikawa
- Department of Maternal-Fetal Biology, National Research Institute for Child Health and Development, Tokyo, Japan
| | - Shuji Takada
- Department of Systems Biomedicine, National Research Institute for Child Health and Development, Tokyo, Japan
| | - Kohji Okamura
- Department of Systems Biomedicine, National Research Institute for Child Health and Development, Tokyo, Japan
| | - Miho Terao
- Department of Systems Biomedicine, National Research Institute for Child Health and Development, Tokyo, Japan
| | - Hiroko Ogata-Kawata
- Department of Maternal-Fetal Biology, National Research Institute for Child Health and Development, Tokyo, Japan
| | - Hidenori Akutsu
- Department of Reproductive Biology, National Research Institute for Child Health and Development, Tokyo, Japan
| | - Satoshi Tanaka
- Laboratory of Cellular Biochemistry, Department of Animal Resource Sciences/Veterinary Medical Sciences, The University of Tokyo, Tokyo, Japan
| | - Kenichiro Hata
- Department of Maternal-Fetal Biology, National Research Institute for Child Health and Development, Tokyo, Japan
| | - Kazuhiko Nakabayashi
- Department of Maternal-Fetal Biology, National Research Institute for Child Health and Development, Tokyo, Japan
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15
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Paranjapye A, Ruffin M, Harris A, Corvol H. Genetic variation in CFTR and modifier loci may modulate cystic fibrosis disease severity. J Cyst Fibros 2020; 19 Suppl 1:S10-S14. [PMID: 31734115 PMCID: PMC7036019 DOI: 10.1016/j.jcf.2019.11.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 11/04/2019] [Accepted: 11/07/2019] [Indexed: 12/11/2022]
Abstract
In patients with cystic fibrosis (CF), genetic variants within and outside the CFTR locus contribute to the variability of the disease severity. CFTR transcription is tightly regulated by cis-regulatory elements (CREs) that control the three-dimensional structure of the locus, chromatin accessibility and transcription factor recruitment. Variants within these CREs may contribute to the pathophysiology and to the phenotypic heterogeneity by altering CFTR transcript abundance. In addition to the CREs, variants outside the CFTR locus, namely "modifiers genes", may also be associated with the clinical variability. This review addresses variants at the CFTR locus itself and CFTR CREs, together with the outcomes of the latest modifier gene studies with respect to the different CF phenotypes.
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Affiliation(s)
- Alekh Paranjapye
- Department of Genetics and Genome Sciences, Case Western Reserve University Medical School, 10900 Euclid Avenue, Cleveland, OH, USA
| | - Manon Ruffin
- Sorbonne Université, INSERM, Centre de Recherche Saint-Antoine, CRSA, Paris, France
| | - Ann Harris
- Department of Genetics and Genome Sciences, Case Western Reserve University Medical School, 10900 Euclid Avenue, Cleveland, OH, USA.
| | - Harriet Corvol
- Sorbonne Université, INSERM, Centre de Recherche Saint-Antoine, CRSA, Paris, France; AP-HP, Hôpital Trousseau, Service de Pneumologie Pédiatrique, Paris, France.
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16
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Bera M, Kalyana Sundaram RV. Chromosome Territorial Organization Drives Efficient Protein Complex Formation: A Hypothesis. THE YALE JOURNAL OF BIOLOGY AND MEDICINE 2019; 92:541-548. [PMID: 31543715 PMCID: PMC6747946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
In eukaryotes, chromosomes often form a transcriptional kissing loop during interphase. We propose that these kissing loops facilitate the formation of protein complexes. mRNA transcripts from these loops could cluster together into phase-separated nuclear granules. Their export into the ER could be ensured by guided diffusion through the inter-chromatin space followed by association with nuclear baskets and export factors. Inside the ER, these mRNAs would form a translation hub. Juxtaposed translation of these mRNAs would increase the cis/trans protein complex assembly among the nascent protein chains. Eukaryotes might employ this pathway to increase complex formation efficiency.
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Affiliation(s)
- Manindra Bera
- To whom all correspondence should be addressed: Manindra Bera, Department of Cell Biology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT USA, 06520; Tel: 203-737-3269,
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17
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Swahn H, Harris A. Cell-Selective Regulation of CFTR Gene Expression: Relevance to Gene Editing Therapeutics. Genes (Basel) 2019; 10:E235. [PMID: 30893953 PMCID: PMC6471542 DOI: 10.3390/genes10030235] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2018] [Revised: 02/26/2019] [Accepted: 02/27/2019] [Indexed: 12/19/2022] Open
Abstract
The cystic fibrosis transmembrane conductance regulator (CFTR) gene is an attractive target for gene editing approaches, which may yield novel therapeutic approaches for genetic diseases such as cystic fibrosis (CF). However, for gene editing to be effective, aspects of the three-dimensional (3D) structure and cis-regulatory elements governing the dynamic expression of CFTR need to be considered. In this review, we focus on the higher order chromatin organization required for normal CFTR locus function, together with the complex mechanisms controlling expression of the gene in different cell types impaired by CF pathology. Across all cells, the CFTR locus is organized into an invariant topologically associated domain (TAD) established by the architectural proteins CCCTC-binding factor (CTCF) and cohesin complex. Additional insulator elements within the TAD also recruit these factors. Although the CFTR promoter is required for basal levels of expression, cis-regulatory elements (CREs) in intergenic and intronic regions are crucial for cell-specific and temporal coordination of CFTR transcription. These CREs are recruited to the promoter through chromatin looping mechanisms and enhance cell-type-specific expression. These features of the CFTR locus should be considered when designing gene-editing approaches, since failure to recognize their importance may disrupt gene expression and reduce the efficacy of therapies.
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Affiliation(s)
- Hannah Swahn
- Department of Genetics and Genome Sciences, Case Western Reserve University, Cleveland, OH 44067, USA.
| | - Ann Harris
- Department of Genetics and Genome Sciences, Case Western Reserve University, Cleveland, OH 44067, USA.
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18
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Fritz AJ, Sehgal N, Pliss A, Xu J, Berezney R. Chromosome territories and the global regulation of the genome. Genes Chromosomes Cancer 2019; 58:407-426. [PMID: 30664301 DOI: 10.1002/gcc.22732] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 01/11/2019] [Accepted: 01/12/2019] [Indexed: 12/29/2022] Open
Abstract
Spatial positioning is a fundamental principle governing nuclear processes. Chromatin is organized as a hierarchy from nucleosomes to Mbp chromatin domains (CD) or topologically associating domains (TADs) to higher level compartments culminating in chromosome territories (CT). Microscopic and sequencing techniques have substantiated chromatin organization as a critical factor regulating gene expression. For example, enhancers loop back to interact with their target genes almost exclusively within TADs, distally located coregulated genes reposition into common transcription factories upon activation, and Mbp CDs exhibit dynamic motion and configurational changes in vivo. A longstanding question in the nucleus field is whether an interactive nuclear matrix provides a direct link between structure and function. The findings of nonrandom radial positioning of CT within the nucleus suggest the possibility of preferential interaction patterns among populations of CT. Sequential labeling up to 10 CT followed by application of computer imaging and geometric graph mining algorithms revealed cell-type specific interchromosomal networks (ICN) of CT that are altered during the cell cycle, differentiation, and cancer progression. It is proposed that the ICN correlate with the global level of genome regulation. These approaches also demonstrated that the large scale 3-D topology of CT is specific for each CT. The cell-type specific proximity of certain chromosomal regions in normal cells may explain the propensity of distinct translocations in cancer subtypes. Understanding how genes are dysregulated upon disruption of the normal "wiring" of the nucleus by translocations, deletions, and amplifications that are hallmarks of cancer, should enable more targeted therapeutic strategies.
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Affiliation(s)
- Andrew J Fritz
- Department of Biochemistry and University of Vermont Cancer Center, The University of Vermont Larner College of Medicine, Burlington, Vermont
| | - Nitasha Sehgal
- Department of Biological Sciences, University at Buffalo, Buffalo, New York
| | - Artem Pliss
- Institute for Lasers, Photonics and Biophotonics and the Department of Chemistry, University at Buffalo, Buffalo, New York
| | - Jinhui Xu
- Department of Computer Science and Engineering, University at Buffalo, Buffalo, New York
| | - Ronald Berezney
- Department of Biological Sciences, University at Buffalo, Buffalo, New York
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19
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Chromosome Conformation Capture Reveals Two Elements That Interact with the PTBP3 ( ROD1) Transcription Start Site. Int J Mol Sci 2019; 20:ijms20020242. [PMID: 30634466 PMCID: PMC6359592 DOI: 10.3390/ijms20020242] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Revised: 12/31/2018] [Accepted: 01/03/2019] [Indexed: 12/21/2022] Open
Abstract
The long-range control of gene expression is facilitated by chromatin looping and can be detected using chromosome conformation capture—3C. Here we focus on the chromatin architecture of the PTBP3 (Polypyrimidine tract binding protein 3) locus to evaluate its potential role in regulating expression of the gene. PTBP3 expression in prostate cancer cell lines is found significantly higher compared to skin fibroblasts using real-time PCR (p < 0.05) and digital droplet PCR (p < 0.01). Exploration of the chromatin spatial architecture of a nearly 200-kb fragment of chromosome 9 encompassing the PTBP3 gene identified two elements located 63 kb upstream and 48 kb downstream of PTBP3, which looped specifically to the PTBP3 promoter. These elements contain histone acetylation patterns characteristic of open chromatin regions with active enhancers. Our results reveal for the first time that long-range chromatin interactions between the −63 kb and +48 kb loci and the PTBP3 promoter regulate the expression of this gene in prostate cancer cells. These interactions support an open chromatin form for the PTBP3 locus in cancer cells and the three-dimensional structural model proposed in this paper.
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20
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Szalaj P, Plewczynski D. Three-dimensional organization and dynamics of the genome. Cell Biol Toxicol 2018; 34:381-404. [PMID: 29568981 PMCID: PMC6133016 DOI: 10.1007/s10565-018-9428-y] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 03/11/2018] [Indexed: 12/30/2022]
Abstract
Genome is a complex hierarchical structure, and its spatial organization plays an important role in its function. Chromatin loops and topological domains form the basic structural units of this multiscale organization and are essential to orchestrate complex regulatory networks and transcription mechanisms. They also form higher-order structures such as chromosomal compartments and chromosome territories. Each level of this intrinsic architecture is governed by principles and mechanisms that we only start to understand. In this review, we summarize the current view of the genome architecture on the scales ranging from chromatin loops to the whole genome. We describe cell-to-cell variability, links between genome reorganization and various genomic processes, such as chromosome X inactivation and cell differentiation, and the interplay between different experimental techniques.
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Affiliation(s)
- Przemyslaw Szalaj
- Centre for Innovative Research, Medical University of Bialystok, Białystok, Poland.
- I-BioStat, Hasselt University, Hasselt, Belgium.
- Centre of New Technologies, University of Warsaw, Warsaw, Poland.
| | - Dariusz Plewczynski
- Centre for Innovative Research, Medical University of Bialystok, Białystok, Poland
- Centre of New Technologies, University of Warsaw, Warsaw, Poland
- Faculty of Mathematics and Information Science, Warsaw University of Technology, Warsaw, Poland
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21
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Strug LJ, Stephenson AL, Panjwani N, Harris A. Recent advances in developing therapeutics for cystic fibrosis. Hum Mol Genet 2018; 27:R173-R186. [PMID: 30060192 PMCID: PMC6061831 DOI: 10.1093/hmg/ddy188] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Revised: 05/07/2018] [Accepted: 05/10/2018] [Indexed: 12/23/2022] Open
Abstract
Despite hope that a cure was imminent when the causative gene was cloned nearly 30 years ago, cystic fibrosis (CF [MIM: 219700]) remains a life-shortening disease affecting more than 70 000 individuals worldwide. However, within the last 6 years the Food and Drug Administration's approval of Ivacaftor, the first drug that corrects the defective cystic fibrosis transmembrane conductance regulator protein [CFTR (MIM: 602421)] in patients with the G551D mutation, marks a watershed in the development of novel therapeutics for this devastating disease. Here we review recent progress in diverse research areas, which all focus on curing CF at the genetic, biochemical or physiological level. In the near future it seems probable that development of mutation-specific therapies will be the focus, since it is unlikely that any one approach will be efficient in correcting the more than 2000 disease-associated variants. We discuss the new drugs and combinations of drugs that either enhance delivery of misfolded CFTR protein to the cell membrane, where it functions as an ion channel, or that activate channel opening. Next we consider approaches to correct the causative genetic lesion at the DNA or RNA level, through repressing stop mutations and nonsense-mediated decay, modulating splice mutations, fixing errors by gene editing or using novel routes to gene replacement. Finally, we explore how modifier genes, loci elsewhere in the genome that modify CF disease severity, may be used to restore a normal phenotype. Progress in all of these areas has been dramatic, generating enthusiasm that CF may soon become a broadly treatable disease.
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Affiliation(s)
- Lisa J Strug
- Division of Biostatistics, Dalla Lana School of Public Health, University of Toronto, Toronto, ON, Canada
- The Centre for Applied Genomics, The Hospital for Sick Children, Toronto, ON, Canada
- Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON, Canada
| | - Anne L Stephenson
- Department of Respirology, Adult Cystic Fibrosis Program, St. Michael’s Hospital, Toronto, ON, Canada
- Institute of Health Policy, Management and Evaluation, University of Toronto, Toronto, ON, Canada
| | - Naim Panjwani
- Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON, Canada
| | - Ann Harris
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, OH, USA
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22
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Punzi G, Bharadwaj R, Ursini G. Neuroepigenetics of Schizophrenia. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2018; 158:195-226. [PMID: 30072054 DOI: 10.1016/bs.pmbts.2018.04.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Schizophrenia is a complex disorder of the brain, where genetic variants explain only a portion of risk. Neuroepigenetic mechanisms may explain the remaining share of risk, as well as the transition from susceptibility to the actual disease. Here, we discuss the most recent findings in the field of brain epigenetics applied to the study of schizophrenia. Methylome studies have found several candidates exhibiting methylation modifications in association with the disorder, but genes affected do not always overlap. Notably, these studies converge in that genes within the schizophrenia risk loci or genes differentially methylated in patients affected with the disorder are dynamically regulated during early life. They also imply that schizophrenia-associated genetic variation may affect DNA methylation in fetal and adult brains. Histone modifications may help mediating the effect of genetic risk variants associated with schizophrenia, and regulating chromatin higher-order structure. The 3D-organization of chromatin in the brain creates physical interactions within chromosomes, so that schizophrenia-associated genetic variants can be linked with genes distant from their loci; this suggests that chromatin conformation matters in the mechanism of risk for the disorder. Non-coding RNAs provide a novel and complex mechanism of gene regulation potentially significant for schizophrenia, as proposed by research on specific microRNAs and long non-coding RNAs (lncRNAs). Finally, a recent study in epitranscriptomics identifies RNA methylation as a further epigenetic mechanism active in human brain and specifically in a portion of the transcriptome associated with schizophrenia susceptibility. These findings indicate that, as expected from the complexity of the brain and its development, several epigenetic mechanisms may intervene in the etiopathogenesis of schizophrenia. An understanding of their roles calls for research approaches integrating the investigation of different epigenetic mechanisms and of environmental and genetic risk, in the context of development.
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Affiliation(s)
- Giovanna Punzi
- Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore, MD, United States
| | - Rahul Bharadwaj
- Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore, MD, United States
| | - Gianluca Ursini
- Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore, MD, United States; Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, United States.
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23
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Abstract
It is well known that the chromosomes are organized in the nucleus and this spatial arrangement of genome play a crucial role in gene regulation and genome stability. Different techniques have been developed and applied to uncover the intrinsic mechanism of genome architecture, especially the chromosome conformation capture (3C) and 3C-derived methods. 3C and 3C-derived techniques provide us approaches to perform high-throughput chromatin architecture assays at the genome scale. However, the advantage and disadvantage of current methodologies of C-technologies have not been discussed extensively. In this review, we described and compared the methodologies of C-technologies used in genome organization studies with an emphasis on Hi-C method. We also discussed the crucial challenges facing current genome architecture studies based on 3C and 3C-derived technologies and the direction of future technologies to address currently outstanding questions in the field. These latest news contribute to our current understanding of genome structure, and provide a comprehensive reference for researchers to choose the appropriate method in future application. We consider that these constantly improving technologies will offer a finer and more accurate contact profiles of entire genome and ultimately reveal specific molecular machines govern its shape and function.
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Abstract
The central role of hormonal 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] is to regulate calcium and phosphorus homeostasis via actions in intestine, kidney, and bone. These and other actions in many cell types not involved in mineral metabolism are mediated by the vitamin D receptor. Recent studies using genome-wide scale techniques have extended fundamental ideas regarding vitamin D-mediated control of gene expression while simultaneously revealing a series of new concepts. This article summarizes the current view of the biological actions of the vitamin D hormone and focuses on new concepts that drive the understanding of the mechanisms through which vitamin D operates.
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Affiliation(s)
- J Wesley Pike
- Department of Biochemistry, University of Wisconsin-Madison, Biochem Addition, Room 543D, 433 Babcock Drive, Madison, WI 53706, USA.
| | - Sylvia Christakos
- Department of Microbiology, Biochemistry and Molecular Genetics, Rutgers, The State University of New Jersey, New Jersey Medical School, 185 South Orange Avenue, Newark, NJ 07103, USA
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25
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Shen C, Liu Y, Shi S, Zhang R, Zhang T, Xu Q, Zhu P, Chen X, Lu F. Long-distance interaction of the integrated HPV fragment with MYC gene and 8q24.22 region upregulating the allele-specific MYC expression in HeLa cells. Int J Cancer 2017; 141:540-548. [PMID: 28470669 PMCID: PMC5518216 DOI: 10.1002/ijc.30763] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Revised: 03/15/2017] [Accepted: 04/24/2017] [Indexed: 12/17/2022]
Abstract
Human papillomavirus (HPV) infection is the most important risk factor for cervical cancer development. In HeLa cell line, the HPV viral genome is integrated at 8q24 in one allele of chromosome 8. It has been reported that the HPV fragment integrated in HeLa genome can cis‐activate the expression of proto‐oncogene MYC, which is located at 500 kb downstream of the integrated site. However, the underlying molecular mechanism of this regulation is unknown. A recent study reported that MYC was highly expressed exclusively from the HPV‐integrated haplotype, and a long‐range chromatin interaction between the integrated HPV fragment and MYC gene has been hypothesized. In this study, we provided the experimental evidences supporting this long‐range chromatin interaction in HeLa cells by using Chromosome Conformation Capture (3C) method. We found that the integrated HPV fragment, MYC and 8q24.22 was close to each other and might form a trimer in spatial location. When knocking out the integrated HPV fragment or 8q24.22 region from chromosome 8 by CRISPR/Cas9 system, the expression of MYC reduced dramatically in HeLa cells. Interestingly, decreased expression was only observed in three from eight cell clones, when only one 8q24.22 allele was knocked out. Functionally, HPV knockout caused senescence‐associated acidic β‐gal activity in HeLa cells. These data indicate a long‐distance interaction of the integrated HPV fragment with MYC gene and 8q24.22 region, providing an alternative mechanism relevant to the carcinogenicity of HPV integration. What's new? Infection with human papillomavirus (HPV) is a well‐established risk factor for cervical cancer. The mechanism by which HPV integration into the host genome influences cervical oncogenesis, however, is not fully understood. Using chromosome conformation capture, the authors of this study provide evidence for carcinogenic involvement of a long‐range chromatin interaction between integrated HPV fragments, the proto‐oncogene MYC, and the 8q24.22 chromosomal region in HeLa cells. Knock‐out of either the integrated HPV fragment or the 8q24.22 region in HeLa cells significantly reduced MYC expression. The findings offer an alternative explanation for the carcinogenic mechanism of HPV viral genome integration.
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Affiliation(s)
- Congle Shen
- Department of Microbiology and Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
| | - Yongzhen Liu
- Department of Microbiology and Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
| | - Shu Shi
- Department of Microbiology and Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
| | - Ruiyang Zhang
- Department of Microbiology and Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
| | - Ting Zhang
- Department of Microbiology and Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
| | - Qiang Xu
- Department of Microbiology and Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
| | - Pengfei Zhu
- Department of Clinical Laboratory, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Xiangmei Chen
- Department of Microbiology and Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
| | - Fengmin Lu
- Department of Microbiology and Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
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Linkages between changes in the 3D organization of the genome and transcription during myotube differentiation in vitro. Skelet Muscle 2017; 7:5. [PMID: 28381300 PMCID: PMC5382473 DOI: 10.1186/s13395-017-0122-1] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Accepted: 02/16/2017] [Indexed: 12/21/2022] Open
Abstract
Background The spatial organization of eukaryotic genomes facilitates and reflects the underlying nuclear processes that are occurring in the cell. As such, the spatial organization of a genome represents a window on the genome biology that enables analysis of the nuclear regulatory processes that contribute to mammalian development. Methods In this study, Hi-C and RNA-seq were used to capture the genome organization and transcriptome in mouse muscle progenitor cells (C2C12 myoblasts) before and after differentiation to myotubes, in the presence or absence of the cytidine analogue AraC. Results We observed significant local and global developmental changes despite high levels of correlation between the myotubes and myoblast genomes. Notably, the genes that exhibited the greatest variation in transcript levels between the different developmental stages were predominately within the euchromatic compartment. There was significant re-structuring and changes in the expression of replication-dependent histone variants within the HIST1 locus. Finally, treating terminally differentiated myotubes with AraC resulted in additional changes to the transcriptome and 3D genome organization of sets of genes that were all involved in pyroptosis. Conclusions Collectively, our results provide evidence for muscle cell-specific responses to developmental and environmental stimuli mediated through a chromatin structure mechanism. Electronic supplementary material The online version of this article (doi:10.1186/s13395-017-0122-1) contains supplementary material, which is available to authorized users.
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27
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Tam KT, Chan PK, Zhang W, Law PP, Tian Z, Fung Chan GC, Philipsen S, Festenstein R, Tan-Un KC. Identification of a novel distal regulatory element of the human Neuroglobin gene by the chromosome conformation capture approach. Nucleic Acids Res 2017; 45:115-126. [PMID: 27651453 PMCID: PMC5224503 DOI: 10.1093/nar/gkw820] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Revised: 08/29/2016] [Accepted: 08/31/2016] [Indexed: 12/24/2022] Open
Abstract
Neuroglobin (NGB) is predominantly expressed in the brain and retina. Studies suggest that NGB exerts protective effects to neuronal cells and is implicated in reducing the severity of stroke and Alzheimer's disease. However, little is known about the mechanisms which regulate the cell type-specific expression of the gene. In this study, we hypothesized that distal regulatory elements (DREs) are involved in optimal expression of the NGB gene. By chromosome conformation capture we identified two novel DREs located -70 kb upstream and +100 kb downstream from the NGB gene. ENCODE database showed the presence of DNaseI hypersensitive and transcription factors binding sites in these regions. Further analyses using luciferase reporters and chromatin immunoprecipitation suggested that the -70 kb region upstream of the NGB gene contained a neuronal-specific enhancer and GATA transcription factor binding sites. Knockdown of GATA-2 caused NGB expression to drop dramatically, indicating GATA-2 as an essential transcription factor for the activation of NGB expression. The crucial role of the DRE in NGB expression activation was further confirmed by the drop in NGB level after CRISPR-mediated deletion of the DRE. Taken together, we show that the NGB gene is regulated by a cell type-specific loop formed between its promoter and the novel DRE.
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MESH Headings
- Binding Sites
- CRISPR-Cas Systems
- Cell Line, Tumor
- Chromosomes, Human, Pair 14/chemistry
- Deoxyribonuclease I/genetics
- Deoxyribonuclease I/metabolism
- GATA2 Transcription Factor/genetics
- GATA2 Transcription Factor/metabolism
- Gene Editing
- Gene Expression Regulation
- Genes, Reporter
- Globins/antagonists & inhibitors
- Globins/genetics
- Globins/metabolism
- HeLa Cells
- Humans
- K562 Cells
- Luciferases/genetics
- Luciferases/metabolism
- Nerve Tissue Proteins/antagonists & inhibitors
- Nerve Tissue Proteins/genetics
- Nerve Tissue Proteins/metabolism
- Neuroglobin
- Neurons/cytology
- Neurons/metabolism
- Organ Specificity
- Protein Binding
- RNA, Guide, CRISPR-Cas Systems/genetics
- RNA, Guide, CRISPR-Cas Systems/metabolism
- RNA, Small Interfering/genetics
- RNA, Small Interfering/metabolism
- Regulatory Elements, Transcriptional
- Signal Transduction
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Affiliation(s)
- Kin Tung Tam
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong S.A.R., China
| | - Ping Kei Chan
- Gene Control Mechanisms and Disease Group, Department of Medicine, Division of Brain Sciences and MRC Clinical Sciences Centre, Imperial College School of Medicine, London W12 0NN, United Kingdom
| | - Wei Zhang
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong S.A.R., China
| | - Pui Pik Law
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong S.A.R., China
- Gene Control Mechanisms and Disease Group, Department of Medicine, Division of Brain Sciences and MRC Clinical Sciences Centre, Imperial College School of Medicine, London W12 0NN, United Kingdom
- Department of Paediatrics and Adolescent Medicine, The University of Hong Kong, Pokfulam Road, Hong Kong S.A.R., China
| | - Zhipeng Tian
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong S.A.R., China
- School of Professional and Continuing Education (HKU SPACE), The University of Hong Kong, Pokfulam Road, Hong Kong S.A.R., China
| | - Godfrey Chi Fung Chan
- Department of Paediatrics and Adolescent Medicine, The University of Hong Kong, Pokfulam Road, Hong Kong S.A.R., China
| | - Sjaak Philipsen
- Department of Cell Biology, Erasmus MC, PO Box 2040, 3000 CA Rotterdam, The Netherlands
| | - Richard Festenstein
- Gene Control Mechanisms and Disease Group, Department of Medicine, Division of Brain Sciences and MRC Clinical Sciences Centre, Imperial College School of Medicine, London W12 0NN, United Kingdom
| | - Kian Cheng Tan-Un
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong S.A.R., China
- School of Professional and Continuing Education (HKU SPACE), The University of Hong Kong, Pokfulam Road, Hong Kong S.A.R., China
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Abstract
Recent advances in chromosome conformation capture technologies are improving the current appreciation of how 3D genome architecture affects its function in different cell types and disease. Long-range chromatin interactions are organized into topologically associated domains, which are known to play a role in constraining gene expression patterns. However, in cancer cells there are alterations in the 3D genome structure, which impacts on gene regulation. Disruption of topologically associated domains architecture can result in alterations in chromatin interactions that bring new regulatory elements and genes together, leading to altered expression of oncogenes and tumor suppressor genes. Here, we discuss the impact of genetic and epigenetic changes in cancer and how this affects the spatial organization of chromatin. Understanding how disruptions to the 3D architecture contribute to the cancer genome will provide novel insights into the principles of epigenetic gene regulation in cancer and mechanisms responsible for cancer associated mutations and rearrangements.
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Affiliation(s)
- Joanna Achinger-Kawecka
- Epigenetics Research Laboratory, Genomics & Epigenetics Division, Garvan Institute of Medical Research, 384 Victoria Street, Darlinghurst, NSW 2010, Australia
- St. Vincent's Clinical School, Faculty of Medicine, University of New South Wales, Darlinghurst, NSW 2010, Australia
| | - Susan J Clark
- Epigenetics Research Laboratory, Genomics & Epigenetics Division, Garvan Institute of Medical Research, 384 Victoria Street, Darlinghurst, NSW 2010, Australia
- St. Vincent's Clinical School, Faculty of Medicine, University of New South Wales, Darlinghurst, NSW 2010, Australia
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29
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Deplancke B, Alpern D, Gardeux V. The Genetics of Transcription Factor DNA Binding Variation. Cell 2016; 166:538-554. [PMID: 27471964 DOI: 10.1016/j.cell.2016.07.012] [Citation(s) in RCA: 244] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Indexed: 12/23/2022]
Abstract
Most complex trait-associated variants are located in non-coding regulatory regions of the genome, where they have been shown to disrupt transcription factor (TF)-DNA binding motifs. Variable TF-DNA interactions are therefore increasingly considered as key drivers of phenotypic variation. However, recent genome-wide studies revealed that the majority of variable TF-DNA binding events are not driven by sequence alterations in the motif of the studied TF. This observation implies that the molecular mechanisms underlying TF-DNA binding variation and, by extrapolation, inter-individual phenotypic variation are more complex than originally anticipated. Here, we summarize the findings that led to this important paradigm shift and review proposed mechanisms for local, proximal, or distal genetic variation-driven variable TF-DNA binding. In addition, we discuss the biomedical implications of these findings for our ability to dissect the molecular role(s) of non-coding genetic variants in complex traits, including disease susceptibility.
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Affiliation(s)
- Bart Deplancke
- Laboratory of Systems Biology and Genetics, Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne and Swiss Institute of Bioinformatics, 1015 Lausanne, Switzerland.
| | - Daniel Alpern
- Laboratory of Systems Biology and Genetics, Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne and Swiss Institute of Bioinformatics, 1015 Lausanne, Switzerland
| | - Vincent Gardeux
- Laboratory of Systems Biology and Genetics, Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne and Swiss Institute of Bioinformatics, 1015 Lausanne, Switzerland
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30
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Vecchio-Pagán B, Blackman SM, Lee M, Atalar M, Pellicore MJ, Pace RG, Franca AL, Raraigh KS, Sharma N, Knowles MR, Cutting GR. Deep resequencing of CFTR in 762 F508del homozygotes reveals clusters of non-coding variants associated with cystic fibrosis disease traits. Hum Genome Var 2016; 3:16038. [PMID: 27917292 PMCID: PMC5121184 DOI: 10.1038/hgv.2016.38] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Revised: 09/13/2016] [Accepted: 09/14/2016] [Indexed: 01/09/2023] Open
Abstract
Extensive phenotypic variability is commonly observed in individuals with Mendelian disorders, even among those with identical genotypes in the disease-causing gene. To determine whether variants within and surrounding CFTR contribute to phenotypic variability in cystic fibrosis (CF), we performed deep sequencing of CFTR in 762 patients homozygous for the common CF-causing variant, F508del. In phase 1, ~200 kb encompassing CFTR and extending 10 kb 5' and 5 kb 3' of the gene was sequenced in 486 F508del homozygotes selected from the extremes of sweat chloride concentration. In phase 2, a 510 kb region, which included the entire topologically associated domain of CFTR, was sequenced in 276 F508del homozygotes drawn from extremes of lung function. An additional 163 individuals who carried F508del and a different CF-causing variant were sequenced to inform haplotype construction. Region-based burden testing of both common and rare variants revealed seven regions of significance (α=0.01), five of which overlapped known regulatory elements or chromatin interactions. Notably, the -80 kb locus known to interact with the CFTR promoter was associated with variation in both CF traits. Haplotype analysis revealed a single rare recombination event (1.9% frequency) in intron 15 of CFTR bearing the F508del variant. Otherwise, the majority of F508del chromosomes were markedly similar, consistent with a single origin of the F508del allele. Together, these high-resolution variant analyses of the CFTR locus suggest a role for non-coding regulatory motifs in trait variation among individuals carrying the common CF allele.
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Affiliation(s)
- Briana Vecchio-Pagán
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Scott M Blackman
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Division of Pediatric Endocrinology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Melissa Lee
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Melis Atalar
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Matthew J Pellicore
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Rhonda G Pace
- Cystic Fibrosis-Pulmonary Research and Treatment Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Arianna L Franca
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Karen S Raraigh
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Neeraj Sharma
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Michael R Knowles
- Cystic Fibrosis-Pulmonary Research and Treatment Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Garry R Cutting
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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31
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Weber B, Zicola J, Oka R, Stam M. Plant Enhancers: A Call for Discovery. TRENDS IN PLANT SCIENCE 2016; 21:974-987. [PMID: 27593567 DOI: 10.1016/j.tplants.2016.07.013] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Revised: 07/18/2016] [Accepted: 07/28/2016] [Indexed: 05/12/2023]
Abstract
Higher eukaryotes typically contain many different cell types, displaying different cellular functions that are influenced by biotic and abiotic cues. The different functions are characterized by specific gene expression patterns mediated by regulatory sequences such as transcriptional enhancers. Recent genome-wide approaches have identified thousands of enhancers in animals, reviving interest in enhancers in gene regulation. Although the regulatory roles of plant enhancers are as crucial as those in animals, genome-wide approaches have only very recently been applied to plants. Here we review characteristics of enhancers at the DNA and chromatin level in plants and other species, their similarities and differences, and techniques widely used for genome-wide discovery of enhancers in animal systems that can be implemented in plants.
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Affiliation(s)
- Blaise Weber
- Swammerdam Institute for Life Sciences, Universiteit van Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Johan Zicola
- Max Planck Institute for Plant Breeding Research, Department Plant Developmental Biology, Carl-von-Linné-Weg 10, 50829 Köln, Germany
| | - Rurika Oka
- Swammerdam Institute for Life Sciences, Universiteit van Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Maike Stam
- Swammerdam Institute for Life Sciences, Universiteit van Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands.
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32
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Sharmin M, Bravo HC, Hannenhalli S. Heterogeneity of transcription factor binding specificity models within and across cell lines. Genome Res 2016; 26:1110-23. [PMID: 27311443 PMCID: PMC4971765 DOI: 10.1101/gr.199166.115] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Accepted: 06/16/2016] [Indexed: 12/24/2022]
Abstract
Complex gene expression patterns are mediated by the binding of transcription factors (TFs) to specific genomic loci. The in vivo occupancy of a TF is, in large part, determined by the TF's DNA binding interaction partners, motivating genomic context-based models of TF occupancy. However, approaches thus far have assumed a uniform TF binding model to explain genome-wide cell-type–specific binding sites. Therefore, the cell type heterogeneity of TF occupancy models, as well as the extent to which binding rules underlying a TF's occupancy are shared across cell types, has not been investigated. Here, we develop an ensemble-based approach (TRISECT) to identify the heterogeneous binding rules for cell-type–specific TF occupancy and analyze the inter-cell-type sharing of such rules. Comprehensive analysis of 23 TFs, each with ChIP-seq data in four to 12 different cell types, shows that by explicitly capturing the heterogeneity of binding rules, TRISECT accurately identifies in vivo TF occupancy. Importantly, many of the binding rules derived from individual cell types are shared across cell types and reveal distinct yet functionally coherent putative target genes in different cell types. Closer inspection of the predicted cell-type–specific interaction partners provides insights into the context-specific functional landscape of a TF. Together, our novel ensemble-based approach reveals, for the first time, a widespread heterogeneity of binding rules, comprising the interaction partners within a cell type, many of which nevertheless transcend cell types. Notably, the putative targets of shared binding rules in different cell types, while distinct, exhibit significant functional coherence.
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Affiliation(s)
- Mahfuza Sharmin
- Department of Computer Science, University of Maryland, College Park, Maryland 20742, USA; Center for Bioinformatics and Computational Biology, University of Maryland, College Park, Maryland 20742, USA
| | - Héctor Corrada Bravo
- Department of Computer Science, University of Maryland, College Park, Maryland 20742, USA; Center for Bioinformatics and Computational Biology, University of Maryland, College Park, Maryland 20742, USA
| | - Sridhar Hannenhalli
- Center for Bioinformatics and Computational Biology, University of Maryland, College Park, Maryland 20742, USA; Department of Cell and Molecular Biology, University of Maryland, College Park, Maryland 20742, USA
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33
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Valton AL, Dekker J. TAD disruption as oncogenic driver. Curr Opin Genet Dev 2016; 36:34-40. [PMID: 27111891 DOI: 10.1016/j.gde.2016.03.008] [Citation(s) in RCA: 147] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Revised: 03/20/2016] [Accepted: 03/22/2016] [Indexed: 12/31/2022]
Abstract
Topologically Associating Domains (TADs) are conserved during evolution and play roles in guiding and constraining long-range regulation of gene expression. Disruption of TAD boundaries results in aberrant gene expression by exposing genes to inappropriate regulatory elements. Recent studies have shown that TAD disruption is often found in cancer cells and contributes to oncogenesis through two mechanisms. One mechanism locally disrupts domains by deleting or mutating a TAD boundary leading to fusion of the two adjacent TADs. The other mechanism involves genomic rearrangements that break up TADs and creates new ones without directly affecting TAD boundaries. Understanding the mechanisms by which TADs form and control long-range chromatin interactions will therefore not only provide insights into the mechanism of gene regulation in general, but will also reveal how genomic rearrangements and mutations in cancer genomes can lead to misregulation of oncogenes and tumor suppressors.
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Affiliation(s)
- Anne-Laure Valton
- Howard Hughes Medical Institute, Program in Systems Biology, Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA 01605-0103, USA
| | - Job Dekker
- Howard Hughes Medical Institute, Program in Systems Biology, Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA 01605-0103, USA.
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34
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Yang R, Kerschner JL, Gosalia N, Neems D, Gorsic LK, Safi A, Crawford GE, Kosak ST, Leir SH, Harris A. Differential contribution of cis-regulatory elements to higher order chromatin structure and expression of the CFTR locus. Nucleic Acids Res 2016; 44:3082-94. [PMID: 26673704 PMCID: PMC4838340 DOI: 10.1093/nar/gkv1358] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Revised: 11/21/2015] [Accepted: 11/24/2015] [Indexed: 12/18/2022] Open
Abstract
Higher order chromatin structure establishes domains that organize the genome and coordinate gene expression. However, the molecular mechanisms controlling transcription of individual loci within a topological domain (TAD) are not fully understood. The cystic fibrosis transmembrane conductance regulator (CFTR) gene provides a paradigm for investigating these mechanisms.CFTR occupies a TAD bordered by CTCF/cohesin binding sites within which are cell-type-selective cis-regulatory elements for the locus. We showed previously that intronic and extragenic enhancers, when occupied by specific transcription factors, are recruited to the CFTR promoter by a looping mechanism to drive gene expression. Here we use a combination of CRISPR/Cas9 editing of cis-regulatory elements and siRNA-mediated depletion of architectural proteins to determine the relative contribution of structural elements and enhancers to the higher order structure and expression of the CFTR locus. We found the boundaries of the CFTRTAD are conserved among diverse cell types and are dependent on CTCF and cohesin complex. Removal of an upstream CTCF-binding insulator alters the interaction profile, but has little effect on CFTR expression. Within the TAD, intronic enhancers recruit cell-type selective transcription factors and deletion of a pivotal enhancer element dramatically decreases CFTR expression, but has minor effect on its 3D structure.
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Affiliation(s)
- Rui Yang
- Human Molecular Genetics Program, Lurie Children's Research Center, Chicago, IL 60614, USA Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Jenny L Kerschner
- Human Molecular Genetics Program, Lurie Children's Research Center, Chicago, IL 60614, USA Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Nehal Gosalia
- Human Molecular Genetics Program, Lurie Children's Research Center, Chicago, IL 60614, USA Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Daniel Neems
- Department of Cell and Molecular Biology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Lidija K Gorsic
- Human Molecular Genetics Program, Lurie Children's Research Center, Chicago, IL 60614, USA Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Alexias Safi
- Division of Medical Genetics, Department of Pediatrics and Center for Genomic and Computational Biology, Duke University Medical School, Durham, NC 27708, USA
| | - Gregory E Crawford
- Division of Medical Genetics, Department of Pediatrics and Center for Genomic and Computational Biology, Duke University Medical School, Durham, NC 27708, USA
| | - Steven T Kosak
- Department of Cell and Molecular Biology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Shih-Hsing Leir
- Human Molecular Genetics Program, Lurie Children's Research Center, Chicago, IL 60614, USA Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Ann Harris
- Human Molecular Genetics Program, Lurie Children's Research Center, Chicago, IL 60614, USA Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
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35
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Hepatocyte nuclear factor 1 coordinates multiple processes in a model of intestinal epithelial cell function. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2016; 1859:591-8. [PMID: 26855178 DOI: 10.1016/j.bbagrm.2016.02.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Revised: 02/01/2016] [Accepted: 02/04/2016] [Indexed: 12/26/2022]
Abstract
Mutations in hepatocyte nuclear factor 1 transcription factors (HNF1α/β) are associated with diabetes. These factors are well studied in the liver, pancreas and kidney, where they direct tissue-specific gene regulation. However, they also have an important role in the biology of many other tissues, including the intestine. We investigated the transcriptional network governed by HNF1 in an intestinal epithelial cell line (Caco2). We used chromatin immunoprecipitation followed by direct sequencing (ChIP-seq) to identify HNF1 binding sites genome-wide. Direct targets of HNF1 were validated using conventional ChIP assays and confirmed by siRNA-mediated depletion of HNF1, followed by RT-qPCR. Gene ontology process enrichment analysis of the HNF1 targets identified multiple processes with a role in intestinal epithelial cell function, including properties of the cell membrane, cellular response to hormones, and regulation of biosynthetic processes. Approximately 50% of HNF1 binding sites were also occupied by other members of the intestinal transcriptional network, including hepatocyte nuclear factor 4A (HNF4A), caudal type homeobox 2 (CDX2), and forkhead box A2 (FOXA2). Depletion of HNF1 in Caco2 cells increases FOXA2 abundance and decreases levels of CDX2, illustrating the coordinated activities of the network. These data suggest that HNF1 plays an important role in regulating intestinal epithelial cell function, both directly and through interactions with other intestinal transcription factors.
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36
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Smith EM, Lajoie BR, Jain G, Dekker J. Invariant TAD Boundaries Constrain Cell-Type-Specific Looping Interactions between Promoters and Distal Elements around the CFTR Locus. Am J Hum Genet 2016; 98:185-201. [PMID: 26748519 PMCID: PMC4716690 DOI: 10.1016/j.ajhg.2015.12.002] [Citation(s) in RCA: 97] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Accepted: 12/03/2015] [Indexed: 11/29/2022] Open
Abstract
Three-dimensional genome structure plays an important role in gene regulation. Globally, chromosomes are organized into active and inactive compartments while, at the gene level, looping interactions connect promoters to regulatory elements. Topologically associating domains (TADs), typically several hundred kilobases in size, form an intermediate level of organization. Major questions include how TADs are formed and how they are related to looping interactions between genes and regulatory elements. Here we performed a focused 5C analysis of a 2.8 Mb chromosome 7 region surrounding CFTR in a panel of cell types. We find that the same TAD boundaries are present in all cell types, indicating that TADs represent a universal chromosome architecture. Furthermore, we find that these TAD boundaries are present irrespective of the expression and looping of genes located between them. In contrast, looping interactions between promoters and regulatory elements are cell-type specific and occur mostly within TADs. This is exemplified by the CFTR promoter that in different cell types interacts with distinct sets of distal cell-type-specific regulatory elements that are all located within the same TAD. Finally, we find that long-range associations between loci located in different TADs are also detected, but these display much lower interaction frequencies than looping interactions within TADs. Interestingly, interactions between TADs are also highly cell-type-specific and often involve loci clustered around TAD boundaries. These data point to key roles of invariant TAD boundaries in constraining as well as mediating cell-type-specific long-range interactions and gene regulation.
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Affiliation(s)
- Emily M Smith
- Program in Systems Biology, Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA, 01605-0103, USA
| | - Bryan R Lajoie
- Program in Systems Biology, Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA, 01605-0103, USA
| | - Gaurav Jain
- Program in Systems Biology, Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA, 01605-0103, USA
| | - Job Dekker
- Program in Systems Biology, Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA, 01605-0103, USA; Howard Hughes Medical Institute.
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37
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Fritz A, Barutcu AR, Martin-Buley L, vanWijnen AJ, Zaidi SK, Imbalzano AN, Lian JB, Stein JL, Stein GS. Chromosomes at Work: Organization of Chromosome Territories in the Interphase Nucleus. J Cell Biochem 2016; 117:9-19. [PMID: 26192137 PMCID: PMC4715719 DOI: 10.1002/jcb.25280] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Accepted: 07/17/2015] [Indexed: 12/26/2022]
Abstract
The organization of interphase chromosomes in chromosome territories (CTs) was first proposed more than one hundred years ago. The introduction of increasingly sophisticated microscopic and molecular techniques, now provide complementary strategies for studying CTs in greater depth than ever before. Here we provide an overview of these strategies and how they are being used to elucidate CT interactions and the role of these dynamically regulated, nuclear-structure building blocks in directly supporting nuclear function in a physiologically responsive manner.
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Affiliation(s)
- Andrew Fritz
- University of Vermont Cancer Center, Department of Biochemistry, University of Vermont College of Medicine, 89 Beaumont Avenue, Burlington, VT 05405, USA
| | - A. Rasim Barutcu
- Department of Cell and Developmental Biology, University of Massachusetts Medical School, 55 Lake Avenue North, Worcester, MA 01655, USA
| | - Lori Martin-Buley
- University of Vermont Cancer Center, Department of Biochemistry, University of Vermont College of Medicine, 89 Beaumont Avenue, Burlington, VT 05405, USA
| | - André J. vanWijnen
- Departments of Orthopedic Surgery and Biochemistry & Molecular Biology, Mayo Clinic, Rochester, MN, USA
| | - Sayyed K. Zaidi
- University of Vermont Cancer Center, Department of Biochemistry, University of Vermont College of Medicine, 89 Beaumont Avenue, Burlington, VT 05405, USA
| | - Anthony N. Imbalzano
- Department of Cell and Developmental Biology, University of Massachusetts Medical School, 55 Lake Avenue North, Worcester, MA 01655, USA
| | - Jane B. Lian
- University of Vermont Cancer Center, Department of Biochemistry, University of Vermont College of Medicine, 89 Beaumont Avenue, Burlington, VT 05405, USA
| | - Janet L. Stein
- University of Vermont Cancer Center, Department of Biochemistry, University of Vermont College of Medicine, 89 Beaumont Avenue, Burlington, VT 05405, USA
| | - Gary S. Stein
- University of Vermont Cancer Center, Department of Biochemistry, University of Vermont College of Medicine, 89 Beaumont Avenue, Burlington, VT 05405, USA
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38
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Moisan S, Berlivet S, Ka C, Le Gac G, Dostie J, Férec C. Analysis of long-range interactions in primary human cells identifies cooperative CFTR regulatory elements. Nucleic Acids Res 2015; 44:2564-76. [PMID: 26615198 PMCID: PMC4824072 DOI: 10.1093/nar/gkv1300] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Accepted: 11/07/2015] [Indexed: 12/19/2022] Open
Abstract
A mechanism by which control DNA elements regulate transcription over large linear genomic distances is by achieving close physical proximity with genes, and looping of the intervening chromatin paths. Alterations of such regulatory 'chromatin looping' systems are likely to play a critical role in human genetic disease at large. Here, we studied the spatial organization of a ≈790 kb locus encompassing the cystic fibrosis transmembrane conductance regulator (CFTR) gene. Dysregulation of CFTR is responsible for cystic fibrosis, which is the most common lethal genetic disorder in Caucasian populations. CFTR is a relatively large gene of 189 kb with a rather complex tissue-specific and temporal expression profile. We used chromatin conformation at the CFTR locus to identify new DNA sequences that regulate its transcription. By comparing 5C chromatin interaction maps of the CFTR locus in expressing and non-expressing human primary cells, we identified several new contact points between the CFTR promoter and its surroundings, in addition to regions featuring previously described regulatory elements. We demonstrate that two of these novel interacting regions cooperatively increase CFTR expression, and suggest that the new enhancer elements located on either side of the gene are brought together through chromatin looping via CTCF.
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Affiliation(s)
- Stéphanie Moisan
- Laboratoire de Génétique Moléculaire et d'Histocompatibilité, Inserm U1078, Université de Brest, SFR ScInBioS, CHRU de Brest, Établissement Français du Sang - Bretagne, Brest, France
| | - Soizik Berlivet
- Department of Biochemistry and Goodman Cancer Research Center, McGill University, Montréal, Québec, H3G 1Y6, Canada
| | - Chandran Ka
- Laboratoire de Génétique Moléculaire et d'Histocompatibilité, Inserm U1078, Université de Brest, SFR ScInBioS, CHRU de Brest, Établissement Français du Sang - Bretagne, Brest, France
| | - Gérald Le Gac
- Laboratoire de Génétique Moléculaire et d'Histocompatibilité, Inserm U1078, Université de Brest, SFR ScInBioS, CHRU de Brest, Établissement Français du Sang - Bretagne, Brest, France
| | - Josée Dostie
- Department of Biochemistry and Goodman Cancer Research Center, McGill University, Montréal, Québec, H3G 1Y6, Canada
| | - Claude Férec
- Laboratoire de Génétique Moléculaire et d'Histocompatibilité, Inserm U1078, Université de Brest, SFR ScInBioS, CHRU de Brest, Établissement Français du Sang - Bretagne, Brest, France
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39
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Abstract
To accommodate genomes in the limited space of the cell nucleus and ensure the correct execution of gene expression programs, genomes are packaged in complex fashion in the three-dimensional cell nucleus. As a consequence of the extensive higher-order organization of chromosomes, distantly located genomic regions on the same or distinct chromosomes undergo long-range interactions. This article discusses the nature of long interactions, mechanisms of their formation, and their emerging functional roles in gene regulation and genome maintenance.
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Affiliation(s)
- Job Dekker
- University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - Tom Misteli
- National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892
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40
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Chromatin Dynamics in the Regulation of CFTR Expression. Genes (Basel) 2015; 6:543-58. [PMID: 26184320 PMCID: PMC4584316 DOI: 10.3390/genes6030543] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Revised: 07/03/2015] [Accepted: 07/07/2015] [Indexed: 12/31/2022] Open
Abstract
The contribution of chromatin dynamics to the regulation of human disease-associated loci such as the cystic fibrosis transmembrane conductance regulator (CFTR) gene has been the focus of intensive experimentation for many years. Recent technological advances in the analysis of transcriptional mechanisms across the entire human genome have greatly facilitated these studies. In this review we describe the complex machinery of tissue-specific regulation of CFTR expression, and put earlier observations in context by incorporating them into datasets generated by the most recent genomics methods. Though the gene promoter is required for CFTR expression, cell-type specific regulatory elements are located elsewhere in the gene and in flanking intergenic regions. Probably within its own topological domain established by the architectural proteins CTCF and cohesin, the CFTR locus utilizes chromatin dynamics to remodel nucleosomes, recruit cell-selective transcription factors, and activate intronic enhancers. These cis-acting elements are then brought to the gene promoter by chromatin looping mechanisms, which establish long-range interactions across the locus. Despite its complexity, the CFTR locus provides a paradigm for elucidating the critical role of chromatin dynamics in the transcription of individual human genes.
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41
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Razin SV, Gavrilov AA, Ulyanov SV. Transcription-controlling regulatory elements of the eukaryotic genome. Mol Biol 2015. [DOI: 10.1134/s0026893315020119] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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42
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Liu L, Jin G, Zhou X. Modeling the relationship of epigenetic modifications to transcription factor binding. Nucleic Acids Res 2015; 43:3873-85. [PMID: 25820421 PMCID: PMC4417166 DOI: 10.1093/nar/gkv255] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Accepted: 03/12/2015] [Indexed: 12/19/2022] Open
Abstract
Transcription factors (TFs) and epigenetic modifications play crucial roles in the regulation of gene expression, and correlations between the two types of factors have been discovered. However, methods for quantitatively studying the correlations remain limited. Here, we present a computational approach to systematically investigating how epigenetic changes in chromatin architectures or DNA sequences relate to TF binding. We implemented statistical analyses to illustrate that epigenetic modifications are predictive of TF binding affinities, without the need of sequence information. Intriguingly, by considering genome locations relative to transcription start sites (TSSs) or enhancer midpoints, our analyses show that different locations display various relationship patterns. For instance, H3K4me3, H3k9ac and H3k27ac contribute more in the regions near TSSs, whereas H3K4me1 and H3k79me2 dominate in the regions far from TSSs. DNA methylation plays relatively important roles when close to TSSs than in other regions. In addition, the results show that epigenetic modification models for the predictions of TF binding affinities are cell line-specific. Taken together, our study elucidates highly coordinated, but location- and cell type-specific relationships between epigenetic modifications and binding affinities of TFs.
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Affiliation(s)
- Liang Liu
- Center for Bioinformatics and Systems Biology, Department of Radiology, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA
| | - Guangxu Jin
- Center for Bioinformatics and Systems Biology, Department of Radiology, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA
| | - Xiaobo Zhou
- Center for Bioinformatics and Systems Biology, Department of Radiology, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA
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43
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Sancho A, Li S, Paul T, Zhang F, Aguilo F, Vashisht A, Balasubramaniyan N, Leleiko NS, Suchy FJ, Wohlschlegel JA, Zhang W, Walsh MJ. CHD6 regulates the topological arrangement of the CFTR locus. Hum Mol Genet 2015; 24:2724-32. [PMID: 25631877 DOI: 10.1093/hmg/ddv032] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Accepted: 01/26/2015] [Indexed: 01/19/2023] Open
Abstract
The control of transcription is regulated through the well-coordinated spatial and temporal interactions between distal genomic regulatory elements required for specialized cell-type and developmental gene expression programs. With recent findings CFTR has served as a model to understand the principles that govern genome-wide and topological organization of distal intra-chromosomal contacts as it relates to transcriptional control. This is due to the extensive characterization of the DNase hypersensitivity sites, modification of chromatin, transcription factor binding sites and the arrangement of these sites in CFTR consistent with the restrictive expression in epithelial cell types. Here, we identified CHD6 from a screen among several chromatin-remodeling proteins as a putative epigenetic modulator of CFTR expression. Moreover, our findings of CTCF interactions with CHD6 are consistent with the role described previously for CTCF in CFTR regulation. Our results now reveal that the CHD6 protein lies within the infrastructure of multiple transcriptional complexes, such as the FACT, PBAF, PAF1C, Mediator, SMC/Cohesion and MLL complexes. This model underlies the fundamental role CHD6 facilitates by tethering cis-acting regulatory elements of CFTR in proximity to these multi-subunit transcriptional protein complexes. Finally, we indicate that CHD6 structurally coordinates a three-dimensional stricture between intragenic elements of CFTR bound by several cell-type specific transcription factors, such as CDX2, SOX18, HNF4α and HNF1α. Therefore, our results reveal new insights into the epigenetic regulation of CFTR expression, whereas the manipulation of CFTR gene topology could be considered for treating specific indications of cystic fibrosis and/or pancreatitis.
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Affiliation(s)
- Ana Sancho
- Departments of Pediatrics, Structural and Chemical Biology
| | | | - Thankam Paul
- Department of Paediatrics, St. George's Hospital, University of London, London SW17 0QT, UK
| | - Fan Zhang
- Laboratory of Bioinformatics, Division of Nephrology, Department of Medicine
| | | | - Ajay Vashisht
- Department of Biological Chemistry and the Institute of Genomics and Proteomics, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Natarajan Balasubramaniyan
- Children's Hospital Research Institute of Colorado, University of Colorado School of Medicine, Aurora, CO 80045, USA and
| | - Neal S Leleiko
- Department of Pediatrics, Division of Gastroenterology, Hasbro Children's Hospital, Brown University School of Medicine, Providence, NY, USA
| | - Frederick J Suchy
- Children's Hospital Research Institute of Colorado, University of Colorado School of Medicine, Aurora, CO 80045, USA and
| | - James A Wohlschlegel
- Department of Biological Chemistry and the Institute of Genomics and Proteomics, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Weijia Zhang
- Laboratory of Bioinformatics, Division of Nephrology, Department of Medicine
| | - Martin J Walsh
- Departments of Pediatrics, Structural and Chemical Biology, Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA,
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44
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Ulianov SV, Gavrilov AA, Razin SV. Nuclear Compartments, Genome Folding, and Enhancer-Promoter Communication. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2015; 315:183-244. [DOI: 10.1016/bs.ircmb.2014.11.004] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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45
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Banerjee AR, Kim YJ, Kim TH. A novel virus-inducible enhancer of the interferon-β gene with tightly linked promoter and enhancer activities. Nucleic Acids Res 2014; 42:12537-54. [PMID: 25348400 PMCID: PMC4227751 DOI: 10.1093/nar/gku1018] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Long-range enhancers of transcription are a key component of the genomic regulatory architecture. Recent studies have identified bi-directionally transcribed RNAs emanating from these enhancers known as eRNAs. However, it remains unclear how tightly coupled eRNA production is with enhancer activity. Through our systematic search for long-range elements that interact with the interferon-β gene, a model system for studying inducible transcription, we have identified a novel enhancer, which we have named L2 that regulates the expression of interferon-β. We have demonstrated its virus-inducible enhancer activity by analyzing epigenomic profiles, transcription factor association, nascent RNA production and activity in reporter assays. This enhancer exhibits intimately linked virus-inducible enhancer and bidirectional promoter activity that is largely dependent on a conserved Interferon Stimulated Response Element and robustly generates virus inducible eRNAs. Notably, its enhancer and promoter activities are fully retained in reporter assays even upon a complete elimination of its associated eRNA sequences. Finally, we show that L2 regulates IFNB1 expression by siRNA knockdown of eRNAs, and the deletion of L2 in a BAC transfection assay. Thus, L2 is a novel enhancer that regulates IFNB1 and whose eRNAs exert significant activity in vivo that is distinct from those activities recapitulated in the luciferase reporter assays.
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Affiliation(s)
- A Raja Banerjee
- Department of Genetics, Yale University, School of Medicine, New Haven, CT 06520, USA
| | - Yoon Jung Kim
- Department of Genetics, Yale University, School of Medicine, New Haven, CT 06520, USA
| | - Tae Hoon Kim
- Department of Biological Sciences, The University of Texas at Dallas, Richardson, TX 75080, USA
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46
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Wortham M, Guo C, Zhang M, Song L, Lee BK, Iyer VR, Furey TS, Crawford GE, Yan H, He Y. Chromatin accessibility mapping identifies mediators of basal transcription and retinoid-induced repression of OTX2 in medulloblastoma. PLoS One 2014; 9:e107156. [PMID: 25198066 PMCID: PMC4157845 DOI: 10.1371/journal.pone.0107156] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Accepted: 08/06/2014] [Indexed: 12/01/2022] Open
Abstract
Despite an emerging understanding of the genetic alterations giving rise to various tumors, the mechanisms whereby most oncogenes are overexpressed remain unclear. Here we have utilized an integrated approach of genomewide regulatory element mapping via DNase-seq followed by conventional reporter assays and transcription factor binding site discovery to characterize the transcriptional regulation of the medulloblastoma oncogene Orthodenticle Homeobox 2 (OTX2). Through these studies we have revealed that OTX2 is differentially regulated in medulloblastoma at the level of chromatin accessibility, which is in part mediated by DNA methylation. In cell lines exhibiting chromatin accessibility of OTX2 regulatory regions, we found that autoregulation maintains OTX2 expression. Comparison of medulloblastoma regulatory elements with those of the developing brain reveals that these tumors engage a developmental regulatory program to drive OTX2 transcription. Finally, we have identified a transcriptional regulatory element mediating retinoid-induced OTX2 repression in these tumors. This work characterizes for the first time the mechanisms of OTX2 overexpression in medulloblastoma. Furthermore, this study establishes proof of principle for applying ENCODE datasets towards the characterization of upstream trans-acting factors mediating expression of individual genes.
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Affiliation(s)
- Matthew Wortham
- Department of Pathology, The Pediatric Brain Tumor Foundation Institute, and The Preston Robert Tisch Brain Tumor Center at Duke, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Changcun Guo
- Department of Pathology, The Pediatric Brain Tumor Foundation Institute, and The Preston Robert Tisch Brain Tumor Center at Duke, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Monica Zhang
- Department of Pathology, The Pediatric Brain Tumor Foundation Institute, and The Preston Robert Tisch Brain Tumor Center at Duke, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Lingyun Song
- Duke Center for Genomic and Computational Biology, Duke University, Durham, North Carolina, United States of America
| | - Bum-Kyu Lee
- Department of Molecular Biosciences, University of Texas at Austin, Austin, Texas, United States of America
| | - Vishwanath R. Iyer
- Department of Molecular Biosciences, University of Texas at Austin, Austin, Texas, United States of America
| | - Terrence S. Furey
- Department of Genetics, Department of Biology, Carolina Center for Genome Sciences, and Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Gregory E. Crawford
- Duke Center for Genomic and Computational Biology, Duke University, Durham, North Carolina, United States of America
- Department of Pediatrics, Division of Medical Genetics, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Hai Yan
- Department of Pathology, The Pediatric Brain Tumor Foundation Institute, and The Preston Robert Tisch Brain Tumor Center at Duke, Duke University Medical Center, Durham, North Carolina, United States of America
- * E-mail: (YH); (HY)
| | - Yiping He
- Department of Pathology, The Pediatric Brain Tumor Foundation Institute, and The Preston Robert Tisch Brain Tumor Center at Duke, Duke University Medical Center, Durham, North Carolina, United States of America
- * E-mail: (YH); (HY)
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47
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Viart V, Bergougnoux A, Bonini J, Varilh J, Chiron R, Tabary O, Molinari N, Claustres M, Taulan-Cadars M. Transcription factors and miRNAs that regulate fetal to adult CFTR expression change are new targets for cystic fibrosis. Eur Respir J 2014; 45:116-28. [PMID: 25186262 DOI: 10.1183/09031936.00113214] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The CFTR gene displays a tightly regulated tissue-specific and temporal expression. Mutations in this gene cause cystic fibrosis (CF). In this study we wanted to identify trans-regulatory elements responsible for CFTR differential expression in fetal and adult lung, and to determine the importance of inhibitory motifs in the CFTR-3'UTR with the aim of developing new tools for the correction of disease-causing mutations within CFTR. We show that lung development-specific transcription factors (FOXA, C/EBP) and microRNAs (miR-101, miR-145, miR-384) regulate the switch from strong fetal to very low CFTR expression after birth. By using miRNome profiling and gene reporter assays, we found that miR-101 and miR-145 are specifically upregulated in adult lung and that miR-101 directly acts on its cognate site in the CFTR-3'UTR in combination with an overlapping AU-rich element. We then designed miRNA-binding blocker oligonucleotides (MBBOs) to prevent binding of several miRNAs to the CFTR-3'UTR and tested them in primary human nasal epithelial cells from healthy individuals and CF patients carrying the p.Phe508del CFTR mutation. These MBBOs rescued CFTR channel activity by increasing CFTR mRNA and protein levels. Our data offer new understanding of the control of the CFTR gene regulation and new putative correctors for cystic fibrosis.
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Affiliation(s)
- Victoria Viart
- INSERM U827, Laboratoire de Génétique de Maladies Rares, Montpellier, France Université Montpellier I, UFR de Médecine, Montpellier, France Laboratoire de Génétique Moléculaire, CHU Montpellier, Montpellier, France
| | - Anne Bergougnoux
- INSERM U827, Laboratoire de Génétique de Maladies Rares, Montpellier, France Laboratoire de Génétique Moléculaire, CHU Montpellier, Montpellier, France
| | - Jennifer Bonini
- INSERM U827, Laboratoire de Génétique de Maladies Rares, Montpellier, France Université Montpellier I, UFR de Médecine, Montpellier, France
| | - Jessica Varilh
- INSERM U827, Laboratoire de Génétique de Maladies Rares, Montpellier, France Laboratoire de Génétique Moléculaire, CHU Montpellier, Montpellier, France
| | - Raphaël Chiron
- Centre de Ressources et de Compétences de la Mucoviscidose (CRCM), CHU Montpellier, Montpellier, France
| | - Olivier Tabary
- CDR St Antoine, INSERM UMR-S 938, Paris, France UPMC Université Paris 06, Paris, France
| | - Nicolas Molinari
- Département d'Information Médicale, CHU Montpellier, Montpellier, France UMR 729 MISTEA, Université Montpellier I, Montpellier, France
| | - Mireille Claustres
- INSERM U827, Laboratoire de Génétique de Maladies Rares, Montpellier, France Université Montpellier I, UFR de Médecine, Montpellier, France Laboratoire de Génétique Moléculaire, CHU Montpellier, Montpellier, France
| | - Magali Taulan-Cadars
- INSERM U827, Laboratoire de Génétique de Maladies Rares, Montpellier, France Université Montpellier I, UFR de Médecine, Montpellier, France
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48
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Gosalia N, Neems D, Kerschner JL, Kosak ST, Harris A. Architectural proteins CTCF and cohesin have distinct roles in modulating the higher order structure and expression of the CFTR locus. Nucleic Acids Res 2014; 42:9612-22. [PMID: 25081205 PMCID: PMC4150766 DOI: 10.1093/nar/gku648] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Revised: 07/02/2014] [Accepted: 07/03/2014] [Indexed: 01/02/2023] Open
Abstract
Higher order chromatin structures across the genome are maintained in part by the architectural proteins CCCTC binding factor (CTCF) and the cohesin complex, which co-localize at many sites across the genome. Here, we examine the role of these proteins in mediating chromatin structure at the cystic fibrosis transmembrane conductance regulator (CFTR) gene. CFTR encompasses nearly 200 kb flanked by CTCF-binding enhancer-blocking insulator elements and is regulated by cell-type-specific intronic enhancers, which loop to the promoter in the active locus. SiRNA-mediated depletion of CTCF or the cohesin component, RAD21, showed that these two factors have distinct roles in regulating the higher order organization of CFTR. CTCF mediates the interactions between CTCF/cohesin binding sites, some of which have enhancer-blocking insulator activity. Cohesin shares this tethering role, but in addition stabilizes interactions between the promoter and cis-acting intronic elements including enhancers, which are also dependent on the forkhead box A1/A2 (FOXA1/A2) transcription factors (TFs). Disruption of the three-dimensional structure of the CFTR gene by depletion of CTCF or RAD21 increases gene expression, which is accompanied by alterations in histone modifications and TF occupancy across the locus, and causes internalization of the gene from the nuclear periphery.
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Affiliation(s)
- Nehal Gosalia
- Human Molecular Genetics Program, Lurie Children's Research Center, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611, USA Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611, USA
| | - Daniel Neems
- Department of Cell and Molecular Biology, Northwestern University Feinberg School of Medicine, Chicago, IL 60614, USA
| | - Jenny L Kerschner
- Human Molecular Genetics Program, Lurie Children's Research Center, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611, USA Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611, USA
| | - Steven T Kosak
- Department of Cell and Molecular Biology, Northwestern University Feinberg School of Medicine, Chicago, IL 60614, USA
| | - Ann Harris
- Human Molecular Genetics Program, Lurie Children's Research Center, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611, USA Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611, USA
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49
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Lohsen S, Majumder P, Scharer CD, Barwick BG, Austin JW, Zinzow-Kramer WM, Boss JM. Common distal elements orchestrate CIITA isoform-specific expression in multiple cell types. Genes Immun 2014; 15:543-55. [PMID: 25101797 PMCID: PMC4257854 DOI: 10.1038/gene.2014.49] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Revised: 07/03/2014] [Accepted: 07/07/2014] [Indexed: 11/13/2022]
Abstract
Major histocompatibility class II (MHC-II) expression is critical for immune responses and is controlled by the MHC-II transactivator CIITA. CIITA is primarily regulated at the transcriptional level and is expressed from three main promoters with myeloid, lymphoid, and IFN-γ treated non-hematopoietic cells using promoters pI, pIII, and pIV, respectively. Recent studies in non-hematopoietic cells suggest a series of distal regulatory elements may be involved in regulating CIITA transcription. To identify distal elements in B cells, a DNase I-hypersensitivity screen was performed, revealing a series of potential novel regulatory elements. These elements were analyzed computationally and biochemically. Several regions displayed active histone modifications and/or enhanced expression of a reporter gene. Four of the elements interacted with pIII in B cells. These same four regions were also found to interact with pI in splenic dendritic cells (spDC). Intriguingly, examination of the above interactions in pI-knockout-derived spDC showed a switch to the next available promoter, pIII. Extensive DNA methylation was found at the pI region in B cells, suggesting that this promoter is not accessible in B cells. Thus, CIITA expression is likely mediated in hematopoietic cells by common elements with promoter accessibility playing a part in promoter choice.
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Affiliation(s)
- S Lohsen
- Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta, GA, USA
| | - P Majumder
- Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta, GA, USA
| | - C D Scharer
- Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta, GA, USA
| | - B G Barwick
- Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta, GA, USA
| | - J W Austin
- Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta, GA, USA
| | - W M Zinzow-Kramer
- Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta, GA, USA
| | - J M Boss
- Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta, GA, USA
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50
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Abstract
Epigenetics refers to functionally relevant modifications of the genome that do not involve a change in the nucleotide sequence. Examples of such modifications are DNA methylation and histone modifications. Both modifications serve to regulate gene expression without altering the underlying DNA sequence. The epigenome encodes critical information to regulate gene expression. The cellular epigenome is established during development and differentiation and maintained during cell division. These instructions are different in each cell type; therefore, the epigenome is cell-type-specific. Nutrient availability and other environmental factors cause changes in the epigenome. Recent research suggests the critical contribution of the epigenome to the development of complex gene-environmental diseases including chronic kidney diseases.
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