101
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Aguirre A, Montserrat N, Zacchigna S, Nivet E, Hishida T, Krause MN, Kurian L, Ocampo A, Vazquez-Ferrer E, Rodriguez-Esteban C, Kumar S, Moresco JJ, Yates JR, Campistol JM, Sancho-Martinez I, Giacca M, Izpisua Belmonte JC. In vivo activation of a conserved microRNA program induces mammalian heart regeneration. Cell Stem Cell 2014; 15:589-604. [PMID: 25517466 DOI: 10.1016/j.stem.2014.10.003] [Citation(s) in RCA: 151] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Revised: 08/19/2014] [Accepted: 10/08/2014] [Indexed: 01/14/2023]
Abstract
Heart failure is a leading cause of mortality and morbidity in the developed world, partly because mammals lack the ability to regenerate heart tissue. Whether this is due to evolutionary loss of regenerative mechanisms present in other organisms or to an inability to activate such mechanisms is currently unclear. Here we decipher mechanisms underlying heart regeneration in adult zebrafish and show that the molecular regulators of this response are conserved in mammals. We identified miR-99/100 and Let-7a/c and their protein targets smarca5 and fntb as critical regulators of cardiomyocyte dedifferentiation and heart regeneration in zebrafish. Although human and murine adult cardiomyocytes fail to elicit an endogenous regenerative response after myocardial infarction, we show that in vivo manipulation of this molecular machinery in mice results in cardiomyocyte dedifferentiation and improved heart functionality after injury. These data provide a proof of concept for identifying and activating conserved molecular programs to regenerate the damaged heart.
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Affiliation(s)
- Aitor Aguirre
- Gene Expression Laboratory, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | - Nuria Montserrat
- Center of Regenerative Medicine of Barcelona (CMRB), 08003 Barcelona, Spain
| | - Serena Zacchigna
- International Center for Genetic Engineering and Biotechnology (ICGEB), 34149 Trieste, Italy
| | - Emmanuel Nivet
- Gene Expression Laboratory, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | - Tomoaki Hishida
- Gene Expression Laboratory, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | - Marie N Krause
- Gene Expression Laboratory, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | - Leo Kurian
- Gene Expression Laboratory, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | - Alejandro Ocampo
- Gene Expression Laboratory, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | - Eric Vazquez-Ferrer
- Gene Expression Laboratory, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | | | - Sachin Kumar
- Gene Expression Laboratory, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | - James J Moresco
- Department of Chemical Physiology, The Scripps Research Institute, 10550 North Torrey Pines Road, SR-11, La Jolla, CA 92037, USA
| | - John R Yates
- Department of Chemical Physiology, The Scripps Research Institute, 10550 North Torrey Pines Road, SR-11, La Jolla, CA 92037, USA
| | - Josep M Campistol
- Renal Division, Hospital Clinic, University of Barcelona, IDIBAPS, 08036 Barcelona, Spain
| | - Ignacio Sancho-Martinez
- Gene Expression Laboratory, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | - Mauro Giacca
- International Center for Genetic Engineering and Biotechnology (ICGEB), 34149 Trieste, Italy
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102
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Joliot V, Ait-Mohamed O, Battisti V, Pontis J, Philipot O, Robin P, Ito H, Ait-Si-Ali S. The SWI/SNF subunit/tumor suppressor BAF47/INI1 is essential in cell cycle arrest upon skeletal muscle terminal differentiation. PLoS One 2014; 9:e108858. [PMID: 25271443 PMCID: PMC4182762 DOI: 10.1371/journal.pone.0108858] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Accepted: 08/26/2014] [Indexed: 12/22/2022] Open
Abstract
Myogenic terminal differentiation is a well-orchestrated process starting with permanent cell cycle exit followed by muscle-specific genetic program activation. Individual SWI/SNF components have been involved in muscle differentiation. Here, we show that the master myogenic differentiation factor MyoD interacts with more than one SWI/SNF subunit, including the catalytic subunit BRG1, BAF53a and the tumor suppressor BAF47/INI1. Downregulation of each of these SWI/SNF subunits inhibits skeletal muscle terminal differentiation but, interestingly, at different differentiation steps and extents. BAF53a downregulation inhibits myotube formation but not the expression of early muscle-specific genes. BRG1 or BAF47 downregulation disrupt both proliferation and differentiation genetic programs expression. Interestingly, BRG1 and BAF47 are part of the SWI/SNF remodeling complex as well as the N-CoR-1 repressor complex in proliferating myoblasts. However, our data show that, upon myogenic differentiation, BAF47 shifts in favor of N-CoR-1 complex. Finally, BRG1 and BAF47 are well-known tumor suppressors but, strikingly, only BAF47 seems essential in the myoblasts irreversible cell cycle exit. Together, our data unravel differential roles for SWI/SNF subunits in muscle differentiation, with BAF47 playing a dual role both in the permanent cell cycle exit and in the regulation of muscle-specific genes.
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Affiliation(s)
- Véronique Joliot
- Université Paris Diderot, Sorbonne Paris Cité, Centre Epigénétique et Destin Cellulaire, UMR7216, Centre National de la Recherche Scientifique CNRS, Université Paris Diderot, Paris, France
| | - Ouardia Ait-Mohamed
- Université Paris Diderot, Sorbonne Paris Cité, Centre Epigénétique et Destin Cellulaire, UMR7216, Centre National de la Recherche Scientifique CNRS, Université Paris Diderot, Paris, France
| | - Valentine Battisti
- Université Paris Diderot, Sorbonne Paris Cité, Centre Epigénétique et Destin Cellulaire, UMR7216, Centre National de la Recherche Scientifique CNRS, Université Paris Diderot, Paris, France
| | - Julien Pontis
- Université Paris Diderot, Sorbonne Paris Cité, Centre Epigénétique et Destin Cellulaire, UMR7216, Centre National de la Recherche Scientifique CNRS, Université Paris Diderot, Paris, France
| | - Ophélie Philipot
- Université Paris Diderot, Sorbonne Paris Cité, Centre Epigénétique et Destin Cellulaire, UMR7216, Centre National de la Recherche Scientifique CNRS, Université Paris Diderot, Paris, France
| | - Philippe Robin
- Université Paris Diderot, Sorbonne Paris Cité, Centre Epigénétique et Destin Cellulaire, UMR7216, Centre National de la Recherche Scientifique CNRS, Université Paris Diderot, Paris, France
| | - Hidenori Ito
- Department of Molecular Neurobiology, Institute for Developmental Research, Aichi Human Service Center, Aichi, Japan
| | - Slimane Ait-Si-Ali
- Université Paris Diderot, Sorbonne Paris Cité, Centre Epigénétique et Destin Cellulaire, UMR7216, Centre National de la Recherche Scientifique CNRS, Université Paris Diderot, Paris, France
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103
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Karbassi E, Vondriska TM. How the proteome packages the genome for cardiovascular development. Proteomics 2014; 14:2115-26. [PMID: 25074278 DOI: 10.1002/pmic.201400131] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Revised: 06/24/2014] [Accepted: 07/28/2014] [Indexed: 11/09/2022]
Abstract
The devastating impact of congenital heart defects has made mechanisms of vertebrate heart and vascular development an active area of study. Because myocyte death is a common feature of acquired cardiovascular diseases and the adult heart does not regenerate, the need exists to understand whether features of the developing heart and vasculature-which are more plastic-can be exploited therapeutically in the disease setting. We know that a core network of transcription factors governs commitment to the cardiovascular lineage, and recent studies using genetic loss-of-function approaches and unbiased genomic studies have revealed the role for various chromatin modulatory events. We reason that chromatin structure itself is a causal feature that influences transcriptome complexity along a developmental continuum, and the purpose of this article is to highlight the areas in which 'omics technologies have the potential to reveal new principles of phenotypic plasticity in development. We review the major mechanisms of chromatin structural regulation, highlighting what is known about their actions to control cardiovascular differentiation. We discuss emergent mechanisms of regulation that have been identified on the basis of genomic and proteomic studies of cardiac nuclei and identify current challenges to an integrated understanding of chromatin structure and cardiovascular phenotype.
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Affiliation(s)
- Elaheh Karbassi
- Departments of Anesthesiology, Medicine and Physiology, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
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104
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Epigenetics in cardiac development, function, and disease. Cell Tissue Res 2014; 356:585-600. [DOI: 10.1007/s00441-014-1887-8] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Accepted: 04/02/2014] [Indexed: 12/13/2022]
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105
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Mathiyalagan P, Keating ST, Du XJ, El-Osta A. Chromatin modifications remodel cardiac gene expression. Cardiovasc Res 2014; 103:7-16. [PMID: 24812277 DOI: 10.1093/cvr/cvu122] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Signalling and transcriptional control involve precise programmes of gene activation and suppression necessary for cardiovascular physiology. Deep sequencing of DNA-bound transcription factors reveals a remarkable complexity of co-activators or co-repressors that serve to alter chromatin modification and regulate gene expression. The regulated complexes characterized by genome-wide mapping implicate the recruitment and exchange of proteins with specific enzymatic activities that include roles for histone acetylation and methylation in key developmental programmes of the heart. As for transcriptional changes in response to pathological stress, co-regulatory complexes are also differentially utilized to regulate genes in cardiac disease. Members of the histone deacetylase (HDAC) family catalyse the removal of acetyl groups from proteins whose pharmacological inhibition has profound effects preventing heart failure. HDACs interact with a complex co-regulatory network of transcription factors, chromatin-remodelling complexes, and specific histone modifiers to regulate gene expression in the heart. For example, the histone methyltransferase (HMT), enhancer of zeste homolog 2 (Ezh2), is regulated by HDAC inhibition and associated with pathological cardiac hypertrophy. The challenge now is to target the activity of enzymes involved in protein modification to prevent or reverse the expression of genes implicated with cardiac hypertrophy. In this review, we discuss the role of HDACs and HMTs with a focus on chromatin modification and gene function as well as the clinical treatment of heart failure.
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Affiliation(s)
- Prabhu Mathiyalagan
- Baker IDI Heart and Diabetes Institute, The Alfred Medical Research and Education Precinct, Melbourne, Victoria 3004, Australia
| | - Samuel T Keating
- Baker IDI Heart and Diabetes Institute, The Alfred Medical Research and Education Precinct, Melbourne, Victoria 3004, Australia
| | - Xiao-Jun Du
- Baker IDI Heart and Diabetes Institute, The Alfred Medical Research and Education Precinct, Melbourne, Victoria 3004, Australia Central Clinical School, Faculty of Medicine, Monash University, Victoria, Australia
| | - Assam El-Osta
- Baker IDI Heart and Diabetes Institute, The Alfred Medical Research and Education Precinct, Melbourne, Victoria 3004, Australia Central Clinical School, Faculty of Medicine, Monash University, Victoria, Australia Department of Pathology, The University of Melbourne, Parkville, Victoria, Australia
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106
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Pi-Roig A, Martin-Blanco E, Minguillon C. Distinct tissue-specific requirements for the zebrafish tbx5 genes during heart, retina and pectoral fin development. Open Biol 2014; 4:140014. [PMID: 24759614 PMCID: PMC4043114 DOI: 10.1098/rsob.140014] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
The transcription factor Tbx5 is expressed in the developing heart, eyes and anterior appendages. Mutations in human TBX5 cause Holt-Oram syndrome, a condition characterized by heart and upper limb malformations. Tbx5-knockout mouse embryos have severely impaired forelimb and heart morphogenesis from the earliest stages of their development. However, zebrafish embryos with compromised tbx5 function show a complete absence of pectoral fins, while heart development is disturbed at significantly later developmental stages and eye development remains to be thoroughly analysed. We identified a novel tbx5 gene in zebrafish--tbx5b--that is co-expressed with its paralogue, tbx5a, in the developing eye and heart and hypothesized that functional redundancy could be occurring in these organs in embryos with impaired tbx5a function. We have now investigated the consequences of tbx5a and/or tbx5b downregulation in zebrafish to reveal that tbx5 genes have essential roles in the establishment of cardiac laterality, dorsoventral retina axis organization and pectoral fin development. Our data show that distinct relationships between tbx5 paralogues are required in a tissue-specific manner to ensure the proper morphogenesis of the three organs in which they are expressed. Furthermore, we uncover a novel role for tbx5 genes in the establishment of correct heart asymmetry in zebrafish embryos.
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Affiliation(s)
- Aina Pi-Roig
- CSIC-Institut de Biologia Molecular de Barcelona, Department of Developmental Biology, Parc Científic de Barcelona, C/Baldiri Reixac, 10, Barcelona 08028, Spain
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107
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Attanasio C, Nord AS, Zhu Y, Blow MJ, Biddie SC, Mendenhall EM, Dixon J, Wright C, Hosseini R, Akiyama JA, Holt A, Plajzer-Frick I, Shoukry M, Afzal V, Ren B, Bernstein BE, Rubin EM, Visel A, Pennacchio LA. Tissue-specific SMARCA4 binding at active and repressed regulatory elements during embryogenesis. Genome Res 2014; 24:920-9. [PMID: 24752179 PMCID: PMC4032856 DOI: 10.1101/gr.168930.113] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The SMARCA4 (also known as BRG1 in humans) chromatin remodeling factor is critical for establishing lineage-specific chromatin states during early mammalian development. However, the role of SMARCA4 in tissue-specific gene regulation during embryogenesis remains poorly defined. To investigate the genome-wide binding landscape of SMARCA4 in differentiating tissues, we engineered a Smarca4FLAG knock-in mouse line. Using ChIP-seq, we identified ∼51,000 SMARCA4-associated regions across six embryonic mouse tissues (forebrain, hindbrain, neural tube, heart, limb, and face) at mid-gestation (E11.5). The majority of these regions was distal from promoters and showed dynamic occupancy, with most distal SMARCA4 sites (73%) confined to a single or limited subset of tissues. To further characterize these regions, we profiled active and repressive histone marks in the same tissues and examined the intersection of informative chromatin states and SMARCA4 binding. This revealed distinct classes of distal SMARCA4-associated elements characterized by activating and repressive chromatin signatures that were associated with tissue-specific up- or down-regulation of gene expression and relevant active/repressed biological pathways. We further demonstrate the predicted active regulatory properties of SMARCA4-associated elements by retrospective analysis of tissue-specific enhancers and direct testing of SMARCA4-bound regions in transgenic mouse assays. Our results indicate a dual active/repressive function of SMARCA4 at distal regulatory sequences in vivo and support its role in tissue-specific gene regulation during embryonic development.
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Affiliation(s)
- Catia Attanasio
- Genomics Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Alex S Nord
- Genomics Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Yiwen Zhu
- Genomics Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Matthew J Blow
- US Department of Energy Joint Genome Institute, Walnut Creek, California 94598, USA
| | - Simon C Biddie
- US Department of Energy Joint Genome Institute, Walnut Creek, California 94598, USA; Addenbrooke's Hospital, Cambridge University NHS Trust, Cambridge CB2 0QQ, United Kingdom
| | - Eric M Mendenhall
- HHMI and Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114, USA
| | - Jesse Dixon
- Ludwig Institute for Cancer Research, UCSD School of Medicine, La Jolla, California 92093, USA
| | - Crystal Wright
- US Department of Energy Joint Genome Institute, Walnut Creek, California 94598, USA
| | - Roya Hosseini
- Genomics Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Jennifer A Akiyama
- Genomics Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Amy Holt
- Genomics Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Ingrid Plajzer-Frick
- Genomics Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Malak Shoukry
- Genomics Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Veena Afzal
- Genomics Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Bing Ren
- Ludwig Institute for Cancer Research, UCSD School of Medicine, La Jolla, California 92093, USA
| | - Bradley E Bernstein
- HHMI and Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114, USA
| | - Edward M Rubin
- Genomics Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA; US Department of Energy Joint Genome Institute, Walnut Creek, California 94598, USA
| | - Axel Visel
- Genomics Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA; US Department of Energy Joint Genome Institute, Walnut Creek, California 94598, USA
| | - Len A Pennacchio
- Genomics Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA; US Department of Energy Joint Genome Institute, Walnut Creek, California 94598, USA
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108
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Mehrotra A, Joe B, de la Serna IL. SWI/SNF chromatin remodeling enzymes are associated with cardiac hypertrophy in a genetic rat model of hypertension. J Cell Physiol 2014; 228:2337-42. [PMID: 23702776 DOI: 10.1002/jcp.24404] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Accepted: 05/09/2013] [Indexed: 01/03/2023]
Abstract
Pathological cardiac hypertrophy is characterized by a sustained increase in cardiomyocyte size and re-activation of the fetal cardiac gene program. Previous studies implicated SWI/SNF chromatin remodeling enzymes as regulators of the fetal cardiac gene program in surgical models of cardiac hypertrophy. Although hypertension is a common risk factor for developing cardiac hypertrophy, there has not yet been any investigation into the role of SWI/SNF enzymes in cardiac hypertrophy using genetic models of hypertension. In this study, we tested the hypothesis that components of the SWI/SNF complex are activated and recruited to promoters that regulate the fetal cardiac gene program in hearts that become hypertrophic as a result of salt induced hypertension. Utilizing the Dahl salt-sensitive (S) rat model, we found that the protein levels of several SWI/SNF subunits required for heart development, Brg1, Baf180, and Baf60c, are elevated in hypertrophic hearts from S rats fed a high salt diet compared with normotensive hearts from Dahl salt-resistant (R) rats fed the same diet. Furthermore, we detected significantly higher levels of SWI/SNF subunit enrichment as well as evidence of more accessible chromatin structure on two fetal cardiac gene promoters in hearts from S rats compared with R rats. Our data implicate SWI/SNF chromatin remodeling enzymes as regulators of gene expression in cardiac hypertrophy resulting from salt induced hypertension. Thus we provide novel insights into the epigenetic mechanisms by which salt induced hypertension leads to cardiac hypertrophy.
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Affiliation(s)
- Aanchal Mehrotra
- Department of Biochemistry and Cancer Biology, University of Toledo College of Medicine and Life Sciences, Toledo, OH
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109
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Abstract
The unremitting demand to replenish differentiated cells in tissues requires efficient mechanisms to generate and regulate stem and progenitor cells. Although master regulatory transcription factors, including GATA binding protein-2 (GATA-2), have crucial roles in these mechanisms, how such factors are controlled in developmentally dynamic systems is poorly understood. Previously, we described five dispersed Gata2 locus sequences, termed the -77, -3.9, -2.8, -1.8, and +9.5 GATA switch sites, which contain evolutionarily conserved GATA motifs occupied by GATA-2 and GATA-1 in hematopoietic precursors and erythroid cells, respectively. Despite common attributes of transcriptional enhancers, targeted deletions of the -2.8, -1.8, and +9.5 sites revealed distinct and unpredictable contributions to Gata2 expression and hematopoiesis. Herein, we describe the targeted deletion of the -3.9 site and mechanistically compare the -3.9 site with other GATA switch sites. The -3.9(-/-) mice were viable and exhibited normal Gata2 expression and steady-state hematopoiesis in the embryo and adult. We established a Gata2 repression/reactivation assay, which revealed unique +9.5 site activity to mediate GATA factor-dependent chromatin structural transitions. Loss-of-function analyses provided evidence for a mechanism in which a mediator of long-range transcriptional control [LIM domain binding 1 (LDB1)] and a chromatin remodeler [Brahma related gene 1 (BRG1)] synergize through the +9.5 site, conferring expression of GATA-2, which is known to promote the genesis and survival of hematopoietic stem cells.
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110
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Bevilacqua A, Willis MS, Bultman SJ. SWI/SNF chromatin-remodeling complexes in cardiovascular development and disease. Cardiovasc Pathol 2014; 23:85-91. [PMID: 24183004 PMCID: PMC3946279 DOI: 10.1016/j.carpath.2013.09.003] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Revised: 09/24/2013] [Accepted: 09/25/2013] [Indexed: 12/19/2022] Open
Abstract
Our understanding of congenital heart defects has been recently advanced by whole exome sequencing projects, which have identified de novo mutations in many genes encoding epigenetic regulators. Notably, multiple subunits of switching defective/sucrose non-fermenting (SWI/SNF) chromatin-remodeling complexes have been identified as strong candidates underlying these defects because they physically and functionally interact with cardiogenic transcription factors critical to cardiac development, such as TBX5, GATA-4, and NKX2-5. While these studies indicate a critical role of SWI/SNF complexes in cardiac development and congenital heart disease, many exciting new discoveries have identified their critical role in the adult heart in both physiological and pathological conditions involving multiple cell types in the heart, including cardiomyocytes, vascular endothelial cells, pericytes, and neural crest cells. This review summarizes the role of SWI/SNF chromatin-remodeling complexes in cardiac development, congenital heart disease, cardiac hypertrophy, and vascular endothelial cell survival. Although the clinical relevance of SWI/SNF mutations has traditionally been focused primarily on their role in tumor suppression, these recent studies illustrate their critical role in the heart whereby they regulate cell proliferation, differentiation, and apoptosis of cardiac derived cell lines.
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Affiliation(s)
- Ariana Bevilacqua
- Department of Pathology & Laboratory Medicine, University of North Carolina, Chapel Hill, NC, USA
| | - Monte S Willis
- Department of Pathology & Laboratory Medicine, University of North Carolina, Chapel Hill, NC, USA; McAllister Heart Institute, University of North Carolina, Chapel Hill, NC, USA.
| | - Scott J Bultman
- Department of Genetics, University of North Carolina, Chapel Hill, Chapel Hill, NC, USA.
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111
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112
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Singh AP, Archer TK. Analysis of the SWI/SNF chromatin-remodeling complex during early heart development and BAF250a repression cardiac gene transcription during P19 cell differentiation. Nucleic Acids Res 2013; 42:2958-75. [PMID: 24335282 PMCID: PMC3950667 DOI: 10.1093/nar/gkt1232] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
The regulatory networks of differentiation programs and the molecular mechanisms of lineage-specific gene regulation in mammalian embryos remain only partially defined. We document differential expression and temporal switching of BRG1-associated factor (BAF) subunits, core pluripotency factors and cardiac-specific genes during post-implantation development and subsequent early organogenesis. Using affinity purification of BRG1 ATPase coupled to mass spectrometry, we characterized the cardiac-enriched remodeling complexes present in E8.5 mouse embryos. The relative abundance and combinatorial assembly of the BAF subunits provides functional specificity to Switch/Sucrose NonFermentable (SWI/SNF) complexes resulting in a unique gene expression profile in the developing heart. Remarkably, the specific depletion of the BAF250a subunit demonstrated differential effects on cardiac-specific gene expression and resulted in arrhythmic contracting cardiomyocytes in vitro. Indeed, the BAF250a physically interacts and functionally cooperates with Nucleosome Remodeling and Histone Deacetylase (NURD) complex subunits to repressively regulate chromatin structure of the cardiac genes by switching open and poised chromatin marks associated with active and repressed gene expression. Finally, BAF250a expression modulates BRG1 occupancy at the loci of cardiac genes regulatory regions in P19 cell differentiation. These findings reveal specialized and novel cardiac-enriched SWI/SNF chromatin-remodeling complexes, which are required for heart formation and critical for cardiac gene expression regulation at the early stages of heart development.
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Affiliation(s)
- Ajeet Pratap Singh
- Laboratory of Molecular Carcinogenesis, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA
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113
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Ferg M, Armant O, Yang L, Dickmeis T, Rastegar S, Strähle U. Gene transcription in the zebrafish embryo: regulators and networks. Brief Funct Genomics 2013; 13:131-43. [PMID: 24152666 DOI: 10.1093/bfgp/elt044] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
The precise spatial and temporal control of gene expression is a key process in the development, maintenance and regeneration of the vertebrate body. A substantial proportion of vertebrate genomes encode genes that control the transcription of the genetic information into mRNA. The zebrafish is particularly well suited to investigate gene regulatory networks underlying the control of gene expression during development due to the external development of its transparent embryos and the increasingly sophisticated tools for genetic manipulation available for this model system. We review here recent data on the analysis of cis-regulatory modules, transcriptional regulators and their integration into gene regulatory networks in the zebrafish, using the developing spinal cord as example.
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Affiliation(s)
- Marco Ferg
- Institute of Toxicology and Genetics, Karlsruhe Institute of Technology (KIT), Postfach 3640, 76021 Karlsruhe, Germany.
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114
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Mathiyalagan P, Keating ST, Du XJ, El-Osta A. Interplay of chromatin modifications and non-coding RNAs in the heart. Epigenetics 2013; 9:101-12. [PMID: 24247090 DOI: 10.4161/epi.26405] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Precisely regulated patterns of gene expression are dependent on the binding of transcription factors and chromatin-associated determinants referred to as co-activators and co-repressors. These regulatory components function with the core transcriptional machinery to serve in critical activities to alter chromatin modification and regulate gene expression. While we are beginning to understand that cell-type specific patterns of gene expression are necessary to achieve selective cardiovascular developmental programs, we still do not know the molecular machineries that localize these determinants in the heart. With clear implications for the epigenetic control of gene expression signatures, the ENCODE (Encyclopedia of DNA Elements) Project Consortium determined that about 90% of the human genome is transcribed while only 1-2% of transcripts encode proteins. Emerging evidence suggests that non-coding RNA (ncRNA) serves as a signal for decoding chromatin modifications and provides a potential molecular basis for cell type-specific and promoter-specific patterns of gene expression. The discovery of the histone methyltransferase enzyme EZH2 in the regulation of gene expression patterns implicated in cardiac hypertrophy suggests a novel role for chromatin-associated ncRNAs and is the focus of this article.
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Affiliation(s)
- Prabhu Mathiyalagan
- Epigenetics in Human Health and Disease Laboratory; Baker IDI Heart and Diabetes Institute; The Alfred Medical Research and Education Precinct; Melbourne, VIC Australia
| | - Samuel T Keating
- Epigenetics in Human Health and Disease Laboratory; Baker IDI Heart and Diabetes Institute; The Alfred Medical Research and Education Precinct; Melbourne, VIC Australia
| | - Xiao-Jun Du
- Experimental Cardiology Laboratory; Baker IDI Heart and Diabetes Institute; Melbourne, VIC Australia
| | - Assam El-Osta
- Epigenetics in Human Health and Disease Laboratory; Baker IDI Heart and Diabetes Institute; The Alfred Medical Research and Education Precinct; Melbourne, VIC Australia; Epigenomics Profiling Facility; Baker IDI Heart and Diabetes Institute; The Alfred Medical Research and Education Precinct; Melbourne, VIC Australia; Department of Pathology; The University of Melbourne; Melbourne, VIC Australia; Faculty of Medicine; Monash University; Melbourne, VIC Australia
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115
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Wong MD, Dazai J, Walls JR, Gale NW, Henkelman RM. Design and implementation of a custom built optical projection tomography system. PLoS One 2013; 8:e73491. [PMID: 24023880 PMCID: PMC3762719 DOI: 10.1371/journal.pone.0073491] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Accepted: 07/23/2013] [Indexed: 11/18/2022] Open
Abstract
Optical projection tomography (OPT) is an imaging modality that has, in the last decade, answered numerous biological questions owing to its ability to view gene expression in 3 dimensions (3D) at high resolution for samples up to several cm3. This has increased demand for a cabinet OPT system, especially for mouse embryo phenotyping, for which OPT was primarily designed for. The Medical Research Council (MRC) Technology group (UK) released a commercial OPT system, constructed by Skyscan, called the Bioptonics OPT 3001 scanner that was installed in a limited number of locations. The Bioptonics system has been discontinued and currently there is no commercial OPT system available. Therefore, a few research institutions have built their own OPT system, choosing parts and a design specific to their biological applications. Some of these custom built OPT systems are preferred over the commercial Bioptonics system, as they provide improved performance based on stable translation and rotation stages and up to date CCD cameras coupled with objective lenses of high numerical aperture, increasing the resolution of the images. Here, we present a detailed description of a custom built OPT system that is robust and easy to build and install. Included is a hardware parts list, instructions for assembly, a description of the acquisition software and a free download site, and methods for calibration. The described OPT system can acquire a full 3D data set in 10 minutes at 6.7 micron isotropic resolution. The presented guide will hopefully increase adoption of OPT throughout the research community, for the OPT system described can be implemented by personnel with minimal expertise in optics or engineering who have access to a machine shop.
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Affiliation(s)
- Michael D. Wong
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
- Mouse Imaging Centre (MICe), Hospital for Sick Children, Toronto, Ontario, Canada
- * E-mail:
| | - Jun Dazai
- Mouse Imaging Centre (MICe), Hospital for Sick Children, Toronto, Ontario, Canada
| | - Johnathon R. Walls
- Regeneron Pharmaceuticals, Tarrytown, New York, United States of America
| | - Nicholas W. Gale
- Regeneron Pharmaceuticals, Tarrytown, New York, United States of America
| | - R. Mark Henkelman
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
- Mouse Imaging Centre (MICe), Hospital for Sick Children, Toronto, Ontario, Canada
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116
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Fang F, Chen D, Yu L, Dai X, Yang Y, Tian W, Cheng X, Xu H, Weng X, Fang M, Zhou J, Gao Y, Chen Q, Xu Y. Proinflammatory stimuli engage Brahma related gene 1 and Brahma in endothelial injury. Circ Res 2013; 113:986-96. [PMID: 23963727 DOI: 10.1161/circresaha.113.301296] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
RATIONALE Endothelial dysfunction inflicted by inflammation is found in a host of cardiovascular pathologies. One hallmark event in this process is the aggregation and adhesion of leukocyte to the vessel wall mediated by the upregulation of adhesion molecules (CAM) in endothelial cells at the transcriptional level. The epigenetic modulator(s) of CAM transactivation and its underlying pathophysiological relevance remain poorly defined. OBJECTIVE Our goal was to determine the involvement of Brahma related gene 1 (Brg1) and Brahma (Brm) in CAM transactivation and its relevance in the pathogenesis of atherosclerosis. METHODS AND RESULTS In the present study, we report that proinflammatory stimuli augmented the expression of Brg1 and Brm in vitro in cultured endothelial cells and in vivo in arteries isolated from rodents. Overexpression of Brg1 and Brm promoted while knockdown of Brg1 and Brm abrogated transactivation of adhesion molecules and leukocyte adhesion induced by inflammatory signals. Brg1 and Brm interacted with and were recruited to the CAM promoters by nuclear factor κB/p65. Conversely, depletion of Brg1 and Brm disrupted the kinetics of p65 binding on CAM promoters and crippled CAM activation. Silencing of Brg1 and Brm also altered key epigenetic changes associated with CAM transactivation. Of intrigue, 17β-estradiol antagonized both the expression and activity of Brg1/Brm. Most importantly, endothelial-targeted elimination of Brg1/Brm conferred atheroprotective effects to Apoe(-/-) mice on a Western diet. CONCLUSIONS Our data suggest that Brg1 and Brm integrate various proinflammatory cues into CAM transactivation and endothelial malfunction and, as such, may serve as potential therapeutic targets in treating inflammation-related cardiovascular diseases.
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Affiliation(s)
- Fei Fang
- From the State Key Laboratory of Reproductive Medicine, and Atherosclerosis Research Center, Provincial Key Laboratory of Cardiovascular Disease; and Department of Pathophysiology, Nanjing Medical University, Nanjing, China
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Moyes KW, Sip CG, Obenza W, Yang E, Horst C, Welikson RE, Hauschka SD, Folch A, Laflamme MA. Human embryonic stem cell-derived cardiomyocytes migrate in response to gradients of fibronectin and Wnt5a. Stem Cells Dev 2013; 22:2315-25. [PMID: 23517131 DOI: 10.1089/scd.2012.0586] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
An improved understanding of the factors that regulate the migration of human embryonic stem cell-derived cardiomyocytes (hESC-CMs) would provide new insights into human heart development and suggest novel strategies to improve their electromechanical integration after intracardiac transplantation. Since nothing has been reported as to the factors controlling hESC-CM migration, we hypothesized that hESC-CMs would migrate in response to the extracellular matrix and soluble signaling molecules previously implicated in heart morphogenesis. To test this, we screened candidate factors by transwell assay for effects on hESC-CM motility, followed by validation via live-cell imaging and/or gap-closure assays. Fibronectin (FN) elicited a haptotactic response from hESC-CMs, with cells seeded on a steep FN gradient showing nearly a fivefold greater migratory activity than cells on uniform FN. Studies with neutralizing antibodies indicated that adhesion and migration on FN are mediated by integrins α-5 and α-V. Next, we screened 10 soluble candidate factors by transwell assay and found that the noncanonical Wnt, Wnt5a, elicited an approximately twofold increase in migration over controls. This effect was confirmed using the gap-closure assay, in which Wnt5a-treated hESC-CMs showed approximately twofold greater closure than untreated cells. Studies with microfluidic-generated Wnt5a gradients showed that this factor was chemoattractive as well as chemokinetic, and Wnt5a-mediated responses were inhibited by the Frizzled-1/2 receptor antagonist, UM206. In summary, hESC-CMs show robust promigratory responses to FN and Wnt5a, findings that have implications on both cardiac development and cell-based therapies.
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Affiliation(s)
- Kara White Moyes
- Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA 98109, USA
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118
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Two novel and functional DNA sequence variants within an upstream enhancer of the human NKX2-5 gene in ventricular septal defects. Gene 2013; 524:152-5. [PMID: 23644027 DOI: 10.1016/j.gene.2013.04.043] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Revised: 03/27/2013] [Accepted: 04/04/2013] [Indexed: 01/08/2023]
Abstract
Mortality in patients with congenital heart disease (CHD) is significantly increased even with successful surgeries. The main causes are late cardiac complications, such as heart failure and arrhythmia, probably due to genetic defects. To date, genetic causes for CHD remain largely unknown. NKX2-5 gene encodes a highly conserved homeobox transcription factor, which is essential to the heart development in embryos and cardiac function in adults. Mutations in NKX2-5 gene have been implicated in diverse types of CHD, including ventricular septal defect (VSD). As NKX2-5 is a dosage-sensitive regulator, we have speculated that changed NKX2-5 levels may mediate CHD development by influencing cardiac gene regulatory network. In previous studies, we have analyzed the NKX2-5 gene promoter and a proximal enhancer in VSD patients. In the present study, we further genetically and functionally analyzed an upstream enhancer of the NKX2-5 gene in large cohorts of VSD patients (n=340) and controls (n=347). Two novel heterozygous DNA sequence variants (DSVs), g.17483576C>G and g.17483564C>T, were identified in three VSD patients, but none in controls. Functionally, these two DSVs significantly decreased the activity of the enhancer (P<0.01). Another novel heterozygous DSV, g.17483557Ins, was found in both VSD patients and controls with similar frequencies (P>0.05). Taken together, our data suggested that the DSVs within the upstream enhancer of the NKX2-5 gene may contribute to a small number of VSD. Therefore, genetic studies of CHD may provide insight into designing novel therapies for adult CHD patients.
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119
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Rana MS, Christoffels VM, Moorman AFM. A molecular and genetic outline of cardiac morphogenesis. Acta Physiol (Oxf) 2013; 207:588-615. [PMID: 23297764 DOI: 10.1111/apha.12061] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2012] [Revised: 10/26/2012] [Accepted: 01/02/2013] [Indexed: 12/15/2022]
Abstract
Perturbations in cardiac development result in congenital heart disease, the leading cause of birth defect-related infant morbidity and mortality. Advances in cardiac developmental biology have significantly augmented our understanding of signalling pathways and transcriptional networks underlying heart formation. Cardiogenesis is initiated with the formation of mesodermal multipotent cardiac progenitor cells and is governed by cross-talk between developmental cues emanating from endodermal, mesodermal and ectodermal cells. The molecular and transcriptional machineries that direct the specification and differentiation of these cardiac precursors are part of an evolutionarily conserved programme that includes the Nkx-, Gata-, Hand-, T-box- and Mef2 family of transcription factors. Unravelling the hierarchical networks governing the fate and differentiation of cardiac precursors is crucial for our understanding of congenital heart disease and future stem cell-based and gene therapies. Recent molecular and genetic lineage analyses have revealed that subpopulations of cardiac progenitor cells follow distinctive specification and differentiation paths, which determine their final contribution to the heart. In the last decade, progenitor cells that contribute to the arterial pole and right ventricle have received much attention, as abnormal development of these cells frequently results in congenital defects of the aortic and pulmonary outlets, representing the most commonly occurring congenital cardiac defects. In this review, we provide an overview of the building plan of the vertebrate four-chambered heart, with a special focus on cardiac progenitor cell specification, differentiation and deployment during arterial pole development.
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Affiliation(s)
- M. S. Rana
- Heart Failure Research Center; Department of Anatomy, Embryology & Physiology; Academic Medical Center; University of Amsterdam; Amsterdam; the Netherlands
| | - V. M. Christoffels
- Heart Failure Research Center; Department of Anatomy, Embryology & Physiology; Academic Medical Center; University of Amsterdam; Amsterdam; the Netherlands
| | - A. F. M. Moorman
- Heart Failure Research Center; Department of Anatomy, Embryology & Physiology; Academic Medical Center; University of Amsterdam; Amsterdam; the Netherlands
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120
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Bruneau BG. Signaling and transcriptional networks in heart development and regeneration. Cold Spring Harb Perspect Biol 2013; 5:a008292. [PMID: 23457256 DOI: 10.1101/cshperspect.a008292] [Citation(s) in RCA: 181] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The mammalian heart is the first functional organ, the first indicator of life. Its normal formation and function are essential for fetal life. Defects in heart formation lead to congenital heart defects, underscoring the finesse with which the heart is assembled. Understanding the regulatory networks controlling heart development have led to significant insights into its lineage origins and morphogenesis and illuminated important aspects of mammalian embryology, while providing insights into human congenital heart disease. The mammalian heart has very little regenerative potential, and thus, any damage to the heart is life threatening and permanent. Knowledge of the developing heart is important for effective strategies of cardiac regeneration, providing new hope for future treatments for heart disease. Although we still have an incomplete picture of the mechanisms controlling development of the mammalian heart, our current knowledge has important implications for embryology and better understanding of human heart disease.
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Affiliation(s)
- Benoit G Bruneau
- Gladstone Institute of Cardiovascular Disease, San Francisco, California 94158, and Department of Pediatrics and Cardiovascular Research Institute, University of California, San Francisco, California 94158, USA.
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121
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P B, C V, E B, HW C. Chromatin immunoprecipitation of adult murine cardiomyocytes. CURRENT PROTOCOLS IN CELL BIOLOGY 2013; Chapter 17:17.14.1-17.14.16. [PMID: 23456601 PMCID: PMC3645876 DOI: 10.1002/0471143030.cb1714s58] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
This unit describes a streamlined two-step protocol for the isolation of adult murine cardiomyocytes with subsequent Chromatin ImmunoPrecipitation (ChIP). Isolation and culturing of cardiomyocytes is a delicate process and the protocol presented here optimizes the combination of cardiomyocyte isolation with ChIP. ChIP is an invaluable method for analyzing molecular interactions occurring between a specific protein (or its post-translationally modified form) and a region of genomic DNA. ChIP has become a widely used technique in the last decade since several groundbreaking studies have focused attention on epigenetics and have identified many epigenetic regulatory mechanisms. However, epigenetics within cardiovascular biology is a new area of focus for many investigators, and we have optimized a method for performing ChIP in adult murine cardiomyocytes, as we feel this will be an important aid to both the cardiovascular field and for the development of cell- and tissue-specific ChIP.
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Affiliation(s)
- Bolli P
- Department of Cardiology, Mount Sinai School of Medicine, New York NY, USA 10029
| | - Vardabasso C
- Departments of Oncological Sciences and Dermatology, Mount Sinai School of Medicine, New York NY, USA 10029
| | - Bernstein E
- Departments of Oncological Sciences and Dermatology, Mount Sinai School of Medicine, New York NY, USA 10029
| | - Chaudhry HW
- Department of Cardiology, Mount Sinai School of Medicine, New York NY, USA 10029,Correspondence to Hina W. Chaudhry, MD, Cardiovascular Regenerative Medicine, Mount Sinai School of Medicine, One Gustave L. Levy Place, Box 1030, New York, NY 10029.
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122
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Xu J, Lei S, Liu Y, Gao X, Irwin MG, Xia ZY, Hei Z, Gan X, Wang T, Xia Z. Antioxidant N-acetylcysteine attenuates the reduction of Brg1 protein expression in the myocardium of type 1 diabetic rats. J Diabetes Res 2013; 2013:716219. [PMID: 23853776 PMCID: PMC3703332 DOI: 10.1155/2013/716219] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/24/2012] [Accepted: 06/01/2013] [Indexed: 02/07/2023] Open
Abstract
Brahma-related gene 1 (Brg1) is a key gene in inducing the expression of important endogenous antioxidant enzymes, including heme oxygenase-1 (HO-1) which is central to cardioprotection, while cardiac HO-1 expression is reduced in diabetes. It is unknown whether or not cardiac Brg1 expression is reduced in diabetes. We hypothesize that cardiac Brg1 expression is reduced in diabetes which can be restored by antioxidant treatment with N-acetylcysteine (NAC). Control (C) and streptozotocin-induced diabetic (D) rats were treated with NAC in drinking water or placebo for 4 weeks. Plasma and cardiac free15-F2t-isoprostane in diabetic rats were increased, accompanied with increased plasma levels of tumor necrosis factor-alpha (TNF-alpha) and interleukin 6 (IL-6), while cardiac Brg1, p-STAT3 and HO-1 protein expression levels were significantly decreased. Left ventricle weight/body weight ratio was higher, while the peak velocities of early (E) and late (A) flow ratio was lower in diabetic than in C rats. NAC normalized tissue and plasma levels of 15-F2t-isoprostane, significantly increased cardiac Brg1, HO-1 and p-STAT3 protein expression levels and reduced TNF-alpha and IL-6, resulting in improved cardiac function. In conclusion, myocardial Brg1 is reduced in diabetes and enhancement of cardiac Brg1 expression may represent a novel mechanism whereby NAC confers cardioprotection.
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Affiliation(s)
- Jinjin Xu
- Department of Anaesthesiology, The University of Hong Kong, HKSAR, Hong Kong
| | - Shaoqing Lei
- Department of Anaesthesiology, The University of Hong Kong, HKSAR, Hong Kong
- Department of Anaesthesiology, Renmin Hospital of Wuhan University, Wuhan 430060, China
| | - Yanan Liu
- Department of Anaesthesiology, The University of Hong Kong, HKSAR, Hong Kong
| | - Xia Gao
- Department of Anaesthesiology, The University of Hong Kong, HKSAR, Hong Kong
| | - Michael G. Irwin
- Department of Anaesthesiology, The University of Hong Kong, HKSAR, Hong Kong
| | - Zhong-yuan Xia
- Department of Anaesthesiology, Renmin Hospital of Wuhan University, Wuhan 430060, China
| | - Ziqing Hei
- Department of Anesthesiology, 3rd Affiliated Hospital of Sun Yat-sen University, Guangzhou 510630, China
| | - Xiaoliang Gan
- Department of Anesthesiology, 3rd Affiliated Hospital of Sun Yat-sen University, Guangzhou 510630, China
| | - Tingting Wang
- Department of Anaesthesiology, The University of Hong Kong, HKSAR, Hong Kong
- Department of Anesthesiology and Critical Care, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, China
- *Tingting Wang: and
| | - Zhengyuan Xia
- Department of Anaesthesiology, The University of Hong Kong, HKSAR, Hong Kong
- Department of Anesthesiology, Affiliated Hospital of Guangdong Medical College, Zhanjiang 524001, China
- *Zhengyuan Xia:
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123
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Biddie SC, John S. Minireview: Conversing with chromatin: the language of nuclear receptors. Mol Endocrinol 2013; 28:3-15. [PMID: 24196351 DOI: 10.1210/me.2013-1247] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Nuclear receptors are transcription factors that are activated by physiological stimuli to bind DNA in the context of chromatin and regulate complex biological pathways. Major advances in nuclear receptor biology have been aided by genome scale examinations of receptor interactions with chromatin. In this review, we summarize the roles of the chromatin landscape in regulating nuclear receptor function. Chromatin acts as a central integrator in the nuclear receptor-signaling axis, operating in distinct temporal modalities. Chromatin effects nuclear receptor action by specifying its genomic localization and interactions with regulatory elements. On receptor binding, changes in chromatin operate as an effector of receptor signaling to modulate transcriptional events. Chromatin is therefore an integral component of the pathways that guide nuclear receptor action in cell-type-specific and cell state-dependent manners.
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Affiliation(s)
- Simon C Biddie
- Addenbrooke's Hospital (S.C.B.), Cambridge University Hospitals National Health Service Foundation Trust, Hills Road, Cambridge CB2 0QQ, United Kingdom; and National Institutes of Health (S.J.), National Cancer Institute, Laboratory for Genome Integrity, Bethesda, Maryland 20892
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124
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Puri PL, Mercola M. BAF60 A, B, and Cs of muscle determination and renewal. Genes Dev 2012; 26:2673-83. [PMID: 23222103 DOI: 10.1101/gad.207415.112] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Developmental biologists have defined many of the diffusible and transcription factors that control muscle differentiation, yet we still have only rudimentary knowledge of the mechanisms that dictate whether a myogenic progenitor cell forms muscle versus alternate lineages, including those that can be pathological in a state of disease or degeneration. Clues about the molecular basis for lineage determination in muscle progenitors are only now emerging from studies of chromatin modifications that avail myogenic genes for transcription, together with analysis of the composition and activities of the chromatin-modifying complexes themselves. Here we review recent progress on muscle determination and explore a unifying theme that environmental cues from the stem or progenitor niche control the selection of specific subunit variants of the switch/sucrose nonfermentable (SWI/SNF) chromatin-modifying complex, creating a combinatorial code that dictates whether cells adopt myogenic versus nonmyogenic cell fates. A key component of the code appears to be the mutually exclusive usage of the a, b, and c variants of the 60-kD structural subunit BAF60 (BRG1/BRM-associated factor 60), of which BAF60c is essential to activate both skeletal and cardiac muscle programs. Since chromatin remodeling governs myogenic fate, the combinatorial assembly of the SWI/SNF complex might be targeted to develop drugs aimed at the therapeutic reduction of compensatory fibrosis and fatty deposition in chronic muscular disorders.
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Affiliation(s)
- Pier Lorenzo Puri
- Muscle Development and Regeneration Program, Sanford-Burnham Medical Research Institute, La Jolla, California 92037, USA.
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125
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Pang S, Shan J, Qiao Y, Ma L, Qin X, Wanyan H, Xing Q, Wu G, Yan B. Genetic and functional analysis of the NKX2-5 gene promoter in patients with ventricular septal defects. Pediatr Cardiol 2012; 33:1355-61. [PMID: 22576768 DOI: 10.1007/s00246-012-0346-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2012] [Accepted: 04/25/2012] [Indexed: 12/18/2022]
Abstract
The ventricular septal defect (VSD) is the most common type of congenital heart disease (CHD). The morbidity and mortality of CHD patients are significantly higher due to late cardiac complications, likely caused by genetic defects. Mutations in cardiac transcription factor genes such as GATA-4, TBX5, and NKX2-5 have been implicated in CHD cases. The NKX2-5 gene, a homeobox gene, is expressed in the developing heart and the adult heart. Because NKX2-5 is a dosage-sensitive regulator during embryonic development, the authors hypothesized that the expression levels of the NKX2-5 gene rather than the mutant protein may play important roles in CHD. In this study, the promoter regions and exon regions of the NKX2-5 gene were bidirectionally sequenced in large cohorts of VSD patients and healthy control subjects. The results showed that a novel sequence variant (g.4574c>deletion), found only in one VSD patient, and a single nucleotide polymorphism (rs118026695), the frequency of which was significantly higher in VSD patients, were identified within the promoter region. Functional analysis confirmed that these sequence variants significantly enhanced the transcriptional activities of the NKX2-5 gene promoter, altering the expression of the NKX2-5 gene and the cardiac gene regulatory network. In addition, a synonymous mutation in the second exon of the NKX2-5 gene was identified in one VSD patient, which may affect the translation process. Therefore, the authors' data provide supportive evidence that mutations in the coding region of the NKX2-5 gene and sequence variants within its promoter region may be among the contributors to the CHD etiology.
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Affiliation(s)
- Shuchao Pang
- Shandong Provincial Key Laboratory of Cardiac Disease Diagnosis and Treatment, Jining Medical University Affiliated Hospital, Jining Medical University, 79 Guhuai Road, Jining, 272029, Shandong, People's Republic of China
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126
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Chiavacci E, Dolfi L, Verduci L, Meghini F, Gestri G, Evangelista AMM, Wilson SW, Cremisi F, Pitto L. MicroRNA 218 mediates the effects of Tbx5a over-expression on zebrafish heart development. PLoS One 2012; 7:e50536. [PMID: 23226307 PMCID: PMC3511548 DOI: 10.1371/journal.pone.0050536] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2012] [Accepted: 10/26/2012] [Indexed: 11/18/2022] Open
Abstract
tbx5, a member of the T-box gene family, encodes one of the key transcription factors mediating vertebrate heart development. Tbx5 function in heart development appears to be exquisitely sensitive to gene dosage, since both haploinsufficiency and gene duplication generate the cardiac abnormalities associated with Holt−Oram syndrome (HOS), a highly penetrant autosomal dominant disease characterized by congenital heart defects of varying severity and upper limb malformation. It is suggested that tight integration of microRNAs and transcription factors into the cardiac genetic circuitry provides a rich and robust array of regulatory interactions to control cardiac gene expression. Based on these considerations, we performed an in silico screening to identify microRNAs embedded in genes highly sensitive to Tbx5 dosage. Among the identified microRNAs, we focused our attention on miR-218-1 that, together with its host gene, slit2, is involved in heart development. We found correlated expression of tbx5 and miR-218 during cardiomyocyte differentiation of mouse P19CL6 cells. In zebrafish embryos, we show that both Tbx5 and miR-218 dysregulation have a severe impact on heart development, affecting early heart morphogenesis. Interestingly, down-regulation of miR-218 is able to rescue the heart defects generated by tbx5 over-expression supporting the notion that miR-218 is a crucial mediator of Tbx5 in heart development and suggesting its possible involvement in the onset of heart malformations.
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Affiliation(s)
| | - Luca Dolfi
- Institute of Clinical Physiology, CNR, Pisa, Italy
| | | | | | - Gaia Gestri
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | | | - Stephen W. Wilson
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | | | - Letizia Pitto
- Institute of Clinical Physiology, CNR, Pisa, Italy
- * E-mail:
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Abstract
The heart as a functional organ first appeared in bilaterians as a single peristaltic pump and evolved through arthropods, fish, amphibians, and finally mammals into a four-chambered engine controlling blood-flow within the body. The acquisition of cardiac complexity in the evolving heart was a product of gene duplication events and the co-option of novel signaling pathways to an ancestral cardiac-specific gene network. T-box factors belong to an evolutionary conserved family of transcriptional regulators with diverse roles in development. Their regulatory functions are integral in the initiation and potentiation of heart development, and mutations in these genes are associated with congenital heart defects. In this review we will discuss the evolutionary conserved cardiac regulatory functions of this family as well as their implication in disease in an aim to facilitate future gene-targeted and regenerative therapeutic remedies.
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Affiliation(s)
- Fadi Hariri
- Institute for Research in Immunology and Cancer (IRIC), Université de Montréal, C.P. 6128, Succursale, Centre-ville Montréal, Quebec, H3C3J7, Canada
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128
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Lai HL, Grachoff M, Marion AL, Khan FF, Warren CM, Chowdhury SA, Wolska BM, Solaro RJ, Geenen DL, Wang QT. Maintenance of adult cardiac function requires the chromatin factor Asxl2. J Mol Cell Cardiol 2012; 53:734-41. [PMID: 23046516 PMCID: PMC3472135 DOI: 10.1016/j.yjmcc.2012.08.014] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2011] [Revised: 08/16/2012] [Accepted: 08/18/2012] [Indexed: 11/17/2022]
Abstract
During development and differentiation, cell type-specific chromatin configurations are set up to facilitate cell type-specific gene expression. Defects in the establishment or the maintenance of the correct chromatin configuration have been associated with diseases ranging from leukemia to muscular dystrophy. The heart expresses many chromatin factors, and we are only beginning to understand their roles in heart development and function. We have previously shown that the chromatin regulator Asxl2 is highly expressed in the murine heart both during development and adulthood. In the absence of Asxl2, there is a significant reduction in trimethylation of histone H3 lysine 27 (H3K27), a histone mark associated with lineage-specific silencing of developmental genes. Here we present evidence that Asxl2 is required for the long-term maintenance of ventricular function and for the maintenance of normal cardiac gene expression. Asxl2(-/-) hearts displayed progressive deterioration of ventricular function. By 10 months of age, there was ~37% reduction in fractional shortening in Asxl2(-/-) hearts compared to wild-type. Analysis of the expression of myofibril proteins suggests that Asxl2 is required for the repression of β-MHC. Asxl2(-/-) hearts did not exhibit hypertrophy, suggesting that the de-repression of β-MHC was not the result of hypertrophic response. Instead, Asxl2 and the histone methyltansferase Ezh2 co-localize to β-MHC promoter, suggesting that Asxl2 directly represses β-MHC. Interrogation of the CardioGenomics database revealed that ASXL2 is down-regulated in the hearts of patients with ischemic or idiopathic dilated cardiomyopathy. We propose that chromatin factors like Asxl2 function in the adult heart to regulate cell type- and stage-specific patterns of gene expression, and the disruption of such regulation may be involved in the etiology and/or development of certain forms of human heart disease.
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MESH Headings
- Animals
- Blood Pressure
- Cardiomyopathy, Dilated/metabolism
- Cardiomyopathy, Dilated/pathology
- Cardiomyopathy, Dilated/physiopathology
- Case-Control Studies
- Cell Size
- Cyclic AMP-Dependent Protein Kinases/metabolism
- Enhancer of Zeste Homolog 2 Protein
- Female
- Gene Expression Regulation
- HEK293 Cells
- Humans
- Male
- Mice
- Mice, 129 Strain
- Mice, Inbred C57BL
- Mice, Knockout
- Myocardium/enzymology
- Myocardium/metabolism
- Myocardium/pathology
- Myocytes, Cardiac/enzymology
- Myocytes, Cardiac/metabolism
- Myocytes, Cardiac/physiology
- Myosin Heavy Chains/genetics
- Myosin Heavy Chains/metabolism
- Phosphorylation
- Polycomb Repressive Complex 2/metabolism
- Promoter Regions, Genetic
- Protein Processing, Post-Translational
- Repressor Proteins/genetics
- Repressor Proteins/metabolism
- Signal Transduction
- Stroke Volume
- Troponin I/metabolism
- Ventricular Function
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Affiliation(s)
- Hsiao-Lei Lai
- Department of Biological Sciences, University of Illinois at Chicago, 900 S Ashland Ave., Chicago, IL 60607, USA
| | - Milana Grachoff
- Department of Medicine, Section of Cardiology and the Center for Cardiovascular Research, University of Illinois at Chicago, 840 S Wood Street, Chicago, IL 60612, USA
| | - Andrea L. Marion
- Department of Biological Sciences, University of Illinois at Chicago, 900 S Ashland Ave., Chicago, IL 60607, USA
| | - Farida F. Khan
- Department of Biological Sciences, University of Illinois at Chicago, 900 S Ashland Ave., Chicago, IL 60607, USA
| | - Chad M. Warren
- Department of Physiology and Biophysics, Center for Cardiovascular Research, College of Medicine, University of Illinois at Chicago, 835 S. Wolcott Ave, Chicago, IL 60612-7342, USA
| | - Shamim A.K. Chowdhury
- Department of Medicine, Section of Cardiology and the Center for Cardiovascular Research, University of Illinois at Chicago, 840 S Wood Street, Chicago, IL 60612, USA
| | - Beata M. Wolska
- Department of Medicine, Section of Cardiology and the Center for Cardiovascular Research, University of Illinois at Chicago, 840 S Wood Street, Chicago, IL 60612, USA
| | - R. John Solaro
- Department of Physiology and Biophysics, Center for Cardiovascular Research, College of Medicine, University of Illinois at Chicago, 835 S. Wolcott Ave, Chicago, IL 60612-7342, USA
| | - David L. Geenen
- Department of Medicine, Section of Cardiology and the Center for Cardiovascular Research, University of Illinois at Chicago, 840 S Wood Street, Chicago, IL 60612, USA
| | - Q. Tian Wang
- Department of Biological Sciences, University of Illinois at Chicago, 900 S Ashland Ave., Chicago, IL 60607, USA
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129
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Lin CJ, Lin CY, Chen CH, Zhou B, Chang CP. Partitioning the heart: mechanisms of cardiac septation and valve development. Development 2012; 139:3277-99. [PMID: 22912411 DOI: 10.1242/dev.063495] [Citation(s) in RCA: 143] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Heart malformations are common congenital defects in humans. Many congenital heart defects involve anomalies in cardiac septation or valve development, and understanding the developmental mechanisms that underlie the formation of cardiac septal and valvular tissues thus has important implications for the diagnosis, prevention and treatment of congenital heart disease. The development of heart septa and valves involves multiple types of progenitor cells that arise either within or outside the heart. Here, we review the morphogenetic events and genetic networks that regulate spatiotemporal interactions between the cells that give rise to septal and valvular tissues and hence partition the heart.
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Affiliation(s)
- Chien-Jung Lin
- Division of Cardiovascular Medicine, Department of Medicine, Stanford Cardiovascular Institute, Stanford University, Stanford, CA 94305, USA
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130
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Smith-Roe SL, Bultman SJ. Combined gene dosage requirement for SWI/SNF catalytic subunits during early mammalian development. Mamm Genome 2012; 24:21-9. [PMID: 23076393 DOI: 10.1007/s00335-012-9433-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2012] [Accepted: 09/10/2012] [Indexed: 01/17/2023]
Abstract
Mammalian SWI/SNF complexes utilize either BRG1 or BRM as alternative catalytic subunits with DNA-dependent ATPase activity to remodel chromatin. Although the two proteins are 75 % identical, broadly expressed, and have similar biochemical activities in vitro, BRG1 is essential for mouse embryonic development, while BRM is dispensable. To investigate whether BRG1 and BRM have overlapping functions during mouse embryogenesis, we performed double-heterozygous intercrosses using constitutive null mutations previously created by gene targeting. The progeny of these crosses had a distribution of genotypes that was significantly skewed relative to their combined gene dosage. This was most pronounced at the top and bottom of the gene dosage hierarchy, with a 1.5-fold overrepresentation of Brg1 (+/+) ;Brm (+/+) mice and a corresponding 1.6-fold underrepresentation of Brg1 (+/-) ;Brm (-/-) mice. To account for the underrepresentation of Brg1 (+/-) ;Brm (-/-) mice, timed matings and blastocyst outgrowth assays demonstrated that ~50 % of these embryos failed to develop beyond the peri-implantation stage. These results challenge the idea that BRG1 is the exclusive catalytic subunit of SWI/SNF complexes in ES cells and suggest that BRM also interacts with the pluripotency transcription factors to facilitate self-renewal of the inner cell mass. In contrast to implantation, the Brm genotype did not influence an exencephaly phenotype that arises because of Brg1 haploinsufficiency during neural tube closure and that results in peri-natal lethality. Taken together, these results support the idea that BRG1 and BRM have overlapping functions for certain developmental processes but not others during embryogenesis.
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Affiliation(s)
- Stephanie L Smith-Roe
- Department of Genetics, University of North Carolina, Chapel Hill, NC 27599-7264, USA
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131
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Qin X, Xing Q, Ma L, Meng H, Liu Y, Pang S, Yan B. Genetic analysis of an enhancer of the NKX2-5 gene in ventricular septal defects. Gene 2012; 508:106-9. [DOI: 10.1016/j.gene.2012.07.019] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2012] [Revised: 07/01/2012] [Accepted: 07/13/2012] [Indexed: 01/23/2023]
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132
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Gaborit N, Sakuma R, Wylie JN, Kim KH, Zhang SS, Hui CC, Bruneau BG. Cooperative and antagonistic roles for Irx3 and Irx5 in cardiac morphogenesis and postnatal physiology. Development 2012; 139:4007-19. [PMID: 22992950 DOI: 10.1242/dev.081703] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The Iroquois homeobox (Irx) homeodomain transcription factors are important for several aspects of embryonic development. In the developing heart, individual Irx genes are important for certain postnatal cardiac functions, including cardiac repolarization (Irx5) and rapid ventricular conduction (Irx3). Irx genes are expressed in dynamic and partially overlapping patterns in the developing heart. Here we show in mice that Irx3 and Irx5 have redundant function in the endocardium to regulate atrioventricular canal morphogenesis and outflow tract formation. Our data suggest that direct transcriptional repression of Bmp10 by Irx3 and Irx5 in the endocardium is required for ventricular septation. A postnatal deletion of Irx3 and Irx5 in the myocardium leads to prolongation of atrioventricular conduction, due in part to activation of expression of the Na(+) channel protein Nav1.5. Surprisingly, combined postnatal loss of Irx3 and Irx5 results in a restoration of the repolarization gradient that is altered in Irx5 mutant hearts, suggesting that postnatal Irx3 activity can be repressed by Irx5. Our results have uncovered complex genetic interactions between Irx3 and Irx5 in embryonic cardiac development and postnatal physiology.
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Affiliation(s)
- Nathalie Gaborit
- Gladstone Institute of Cardiovascular Disease, San Francisco, CA 94158, USA
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133
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Staudt D, Stainier D. Uncovering the molecular and cellular mechanisms of heart development using the zebrafish. Annu Rev Genet 2012; 46:397-418. [PMID: 22974299 DOI: 10.1146/annurev-genet-110711-155646] [Citation(s) in RCA: 201] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Over the past 20 years, the zebrafish has emerged as a powerful model organism for studying cardiac development. Its ability to survive without an active circulation and amenability to forward genetics has led to the identification of numerous mutants whose study has helped elucidate new mechanisms in cardiac development. Furthermore, its transparent, externally developing embryos have allowed detailed cellular analyses of heart development. In this review, we discuss the molecular and cellular processes involved in zebrafish heart development from progenitor specification to development of the valve and the conduction system. We focus on imaging studies that have uncovered the cellular bases of heart development and on zebrafish mutants with cardiac abnormalities whose study has revealed novel molecular pathways in cardiac cell specification and tissue morphogenesis.
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Affiliation(s)
- David Staudt
- Department of Biochemistry and Biophysics, University of California, San Francisco, California 94158, USA
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134
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Shan J, Pang S, Qiao Y, Ma L, Wang H, Xing Q, Wanyan H, Wu G, Yan B. Functional analysis of the novel sequence variants within TBX5 gene promoter in patients with ventricular septal defects. Transl Res 2012; 160:237-8. [PMID: 22901678 DOI: 10.1016/j.trsl.2012.04.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2012] [Revised: 04/06/2012] [Accepted: 04/09/2012] [Indexed: 10/28/2022]
Affiliation(s)
- Jiping Shan
- Shandong Provincial Key Laboratory of Cardiac Disease Diagnosis and Treatment, Jining Medical College Affiliated Hospital, Jining Medical College, Jining, Shandong, China
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135
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Willis MS, Homeister JW, Rosson GB, Annayev Y, Holley D, Holly SP, Madden VJ, Godfrey V, Parise LV, Bultman SJ. Functional redundancy of SWI/SNF catalytic subunits in maintaining vascular endothelial cells in the adult heart. Circ Res 2012; 111:e111-22. [PMID: 22740088 DOI: 10.1161/circresaha.112.265587] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
RATIONALE Mating type switching/sucrose non-fermenting (SWI/SNF) chromatin-remodeling complexes utilize either BRG1 or BRM as a catalytic subunit to alter nucleosome position and regulate gene expression. BRG1 is required for vascular endothelial cell (VEC) development and embryonic survival, whereas BRM is dispensable. OBJECTIVE To circumvent embryonic lethality and study Brg1 function in adult tissues, we used conditional gene targeting. To evaluate possible Brg1-Brm redundancy, we analyzed Brg1 mutant mice on wild-type and Brm-deficient backgrounds. METHODS AND RESULTS The inducible Mx1-Cre driver was used to mutate Brg1 in adult mice. These conditional-null mutants exhibited a tissue-specific phenotype and unanticipated functional compensation between Brg1 and Brm. Brg1 single mutants were healthy and had a normal lifespan, whereas Brg1/Brm double mutants exhibited cardiovascular defects and died within 1 month. BRG1 and BRM were required for the viability of VECs but not other cell types where both genes were also knocked out. The VEC phenotype was most evident in the heart, particularly in the microvasculature of the outer myocardium, and was recapitulated in primary cells ex vivo. VEC death resulted in vascular leakage, cardiac hemorrhage, secondary death of cardiomyocytes due to ischemia, and ventricular dissections. CONCLUSIONS BRG1-catalyzed SWI/SNF complexes are particularly important in cardiovascular tissues. However, in contrast to embryonic development, in which Brm does not compensate, Brg1 is required in adult VECs only when Brm is also mutated. These results demonstrate for the first time that Brm functionally compensates for Brg1 in vivo and that there are significant changes in the relative importance of BRG1- and BRM-catalyzed SWI/SNF complexes during the development of an essential cell lineage.
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Affiliation(s)
- Monte S Willis
- 120 Mason Farm Rd, Genetic Medicine Bldg, Room 5060, Chapel Hill, NC 27516-7264, USA
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136
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Tu S, Chi NC. Zebrafish models in cardiac development and congenital heart birth defects. Differentiation 2012; 84:4-16. [PMID: 22704690 DOI: 10.1016/j.diff.2012.05.005] [Citation(s) in RCA: 77] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Revised: 05/02/2012] [Accepted: 05/21/2012] [Indexed: 12/31/2022]
Abstract
The zebrafish has become an ideal vertebrate animal system for investigating cardiac development due to its genetic tractability, external fertilization, early optical clarity and ability to survive without a functional cardiovascular system during development. In particular, recent advances in imaging techniques and the creation of zebrafish transgenics now permit the in vivo analysis of the dynamic cellular events that transpire during cardiac morphogenesis. As a result, the combination of these salient features provides detailed insight as to how specific genes may influence cardiac development at the cellular level. In this review, we will highlight how the zebrafish has been utilized to elucidate not only the underlying mechanisms of cardiac development and human congenital heart diseases (CHDs), but also potential pathways that may modulate cardiac regeneration. Thus, we have organized this review based on the major categories of CHDs-structural heart, functional heart, and vascular/great vessel defects, and will conclude with how the zebrafish may be further used to contribute to our understanding of specific human CHDs in the future.
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Affiliation(s)
- Shu Tu
- Department of Medicine, Division of Cardiology, University of California, San Diego, CA 92093-0613J, USA
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137
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Lei I, Gao X, Sham MH, Wang Z. SWI/SNF protein component BAF250a regulates cardiac progenitor cell differentiation by modulating chromatin accessibility during second heart field development. J Biol Chem 2012; 287:24255-62. [PMID: 22621927 DOI: 10.1074/jbc.m112.365080] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
ATP-dependent SWI/SNF chromatin remodeling complexes alter the structure of chromatin at specific loci and facilitate tissue-specific gene regulation during development. Several SWI/SNF subunits are required for cardiogenesis. However, the function and mechanisms of SWI/SNF in mediating cardiac progenitor cell (CPC) differentiation during cardiogenesis are not well understood. Our studies of the SWI/SNF chromatin remodeling complex identified that BAF250a, a regulatory subunit of the SWI/SNF, plays a key role in CPC differentiation. BAF250a ablation in mouse second heart field (SHF) led to trabeculation defects in the right ventricle, ventricular septal defect, persistent truncus arteriosus, reduced myocardial proliferation, and embryonic lethality around E13. Using an embryonic stem cell culture system that models the formation and differentiation of SHF CPCs in vivo, we have shown that BAF250a ablation in CPCs specifically inhibits cardiomyocyte formation. Moreover, BAF250a selectively regulates the expression of key cardiac factors Mef2c, Nkx2.5, and Bmp10 in SHF CPCs. Chromatin immunoprecipitation and DNase I digestion assays indicate that BAF250a regulates gene expression by binding selectively to its target gene promoters and recruiting Brg1, the catalytic subunit of SWI/SNF, to modulate chromatin accessibility. Our results thus identify BAF250a-mediated chromatin remodeling as an essential epigenetic mechanism mediating CPC differentiation.
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Affiliation(s)
- Ienglam Lei
- Cardiovascular Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114, USA
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138
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Wang QT. Epigenetic regulation of cardiac development and function by polycomb group and trithorax group proteins. Dev Dyn 2012; 241:1021-33. [PMID: 22514007 DOI: 10.1002/dvdy.23796] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/11/2012] [Indexed: 12/29/2022] Open
Abstract
Heart disease is a leading cause of death and disability in developed countries. Heart disease includes a broad range of diseases that affect the development and/or function of the cardiovascular system. Some of these diseases, such as congenital heart defects, are present at birth. Others develop over time and may be influenced by both genetic and environmental factors. Many of the known heart diseases are associated with abnormal expression of genes. Understanding the factors and mechanisms that regulate gene expression in the heart is essential for the detection, treatment, and prevention of heart diseases. Polycomb Group (PcG) and Trithorax Group (TrxG) proteins are special families of chromatin factors that regulate developmental gene expression in many tissues and organs. Accumulating evidence suggests that these proteins are important regulators of development and function of the heart as well. A better understanding of their roles and functional mechanisms will translate into new opportunities for combating heart disease.
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Affiliation(s)
- Q Tian Wang
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois 60607, USA.
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139
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Qiao Y, Wanyan H, Xing Q, Xie W, Pang S, Shan J, Yan B. Genetic analysis of the TBX20 gene promoter region in patients with ventricular septal defects. Gene 2012; 500:28-31. [DOI: 10.1016/j.gene.2012.03.055] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2012] [Revised: 03/05/2012] [Accepted: 03/13/2012] [Indexed: 01/08/2023]
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140
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Wu G, Shan J, Pang S, Wei X, Zhang H, Yan B. Genetic analysis of the promoter region of the GATA4 gene in patients with ventricular septal defects. Transl Res 2012; 159:376-82. [PMID: 22500510 DOI: 10.1016/j.trsl.2011.10.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2011] [Revised: 10/21/2011] [Accepted: 10/27/2011] [Indexed: 01/06/2023]
Abstract
Ventricular septal defects (VSDs) are the most common type of congenital heart diseases (CHDs). To date, the genetic causes for sporadic VSDs remain largely unknown. GATA transcription factor 4 (GATA4) is a zinc-finger transcription factor that is expressed in developing heart and adult cardiomyocytes. Mutations in the coding region of the GATA4 gene have been identified in CHD patients, including VSD. As the GATA4 factor is a dosage-sensitive regulator, we hypothesized that the promoter region variants of the GATA4 gene may be genetic causes of VSD. In this study, we analyzed the promoter region of the GATA4 gene by bidirectional sequencing in 172 VSD patients and 171 healthy controls. The results showed that 5 heterozygous sequence variants (NG_008177:g.4071T>C, NG_008177:g.4148C>A, NG_008177:g.4566C>T, NG_008177:g.4653G>T, and NG_008177:g.4690G>deletion) within the promoter region of the GATA gene were identified in 5 VSD patients, but in none of controls. One heterozygous sequence variant (g.4762C>A) was found only in one control, which may have no functional significance. A functional analysis revealed that the transcriptional activity of variant NG_008177:g.4566C>T was reduced significantly, whereas the transcriptional activities of the variants (NG_008177:g.4071T>C, NG_008177:g.4148C>A, NG_008177:g.4653G>T, and NG_008177:g.4690G>deletion) were increased significantly compared with the wild-type GATA4 gene promoter. As GATA4 is a dosage-sensitive regulator during development, our data suggest that these sequence variants within the promoter region of the GATA4 gene may contribute to the VSD etiology by altering its gene expression. Additional studies in experimental animals will deepen our understanding of the genetic basis of VSD and shed light on designing novel molecular therapies for adult VSD patients carrying these variants.
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Affiliation(s)
- Guanghua Wu
- Shandong Provincial Key Laboratory of Cardiac Disease Diagnosis and Treatment, Jining Medical College Affiliated Hospital, Jining Medical College, Jining, Shandong 272029, China
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141
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Chen L, Fulcoli FG, Ferrentino R, Martucciello S, Illingworth EA, Baldini A. Transcriptional control in cardiac progenitors: Tbx1 interacts with the BAF chromatin remodeling complex and regulates Wnt5a. PLoS Genet 2012; 8:e1002571. [PMID: 22438823 PMCID: PMC3305383 DOI: 10.1371/journal.pgen.1002571] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2011] [Accepted: 01/16/2012] [Indexed: 12/13/2022] Open
Abstract
Mutations of the Wnt5a gene, encoding a ligand of the non-canonical Wnt pathway, and the Ror2 gene, encoding its receptor, have been found in patients with cardiac outflow tract defects. We found that Wnt5a is expressed in the second heart field (SHF), a population of cardiac progenitor cells destined to populate the cardiac outflow tract and the right ventricle. Because of cardiac phenotype similarities between Wnt5a and Tbx1 mutant mice, we tested potential interactions between the two genes. We found a strong genetic interaction in vivo and determined that the loss of both genes caused severe hypoplasia of SHF–dependent segments of the heart. We demonstrated that Wnt5a is a transcriptional target of Tbx1 and explored the mechanisms of gene regulation. Tbx1 occupies T-box binding elements within the Wnt5a gene and interacts with the Baf60a/Smarcd1 subunit of a chromatin remodeling complex. It also interacts with the Setd7 histone H3K4 monomethyltransferase. Tbx1 enhances Baf60a occupation at the Wnt5a gene and enhances its H3K4 monomethylation status. Finally, we show that Baf60a is required for Tbx1–driven regulation of target genes. These data suggest a model in which Tbx1 interacts with, and probably recruits a specific subunit of, the BAF complex as well as histone methylases to activate or enhance transcription. We speculate that this may be a general mechanism of T-box function and that Baf60a is a key component of the transcriptional control in cardiac progenitors. We have demonstrated a novel interaction between the Tbx1 gene, the mutation of which causes DiGeorge syndrome, and Wnt5a, another human disease gene, which is important for oriented cell migration and cell polarity. We found that, in mice, reduced dosage of each of the two genes enhances the phenotype caused by the mutation of the other. Loss of the two genes in mice has very severe consequences for heart development. Our genetic and biochemical data determined that Tbx1, a transcription factor of the T-box family, regulates Wnt5a expression. We found that Tbx1 targets the BAF chromatin remodeling complex to the Wnt5a gene and interacts with a histone monomethyltransferase. Tbx1 expression increases Baf60a occupation of the Wnt5a gene and enhances its H3K4 monomethylation status, while Baf60a knockdown abolishes the ability of Tbx1 to regulate Wnt5a and other target genes. Overall, our data identify Wnt5a as an important effector of Tbx1 function in heart development and demonstrate that Tbx1 regulates the gene by interacting with the chromatin remodeling and histone methylation machinery.
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Affiliation(s)
- Li Chen
- Texas Heart Institute, Houston, Texas, United States of America
| | - Filomena Gabriella Fulcoli
- Institute of Genetics and Biophysics “Adriano Buzzati Traverso,” National Research Council, Naples, Italy
| | - Rosa Ferrentino
- Institute of Genetics and Biophysics “Adriano Buzzati Traverso,” National Research Council, Naples, Italy
| | | | - Elizabeth A. Illingworth
- Institute of Genetics and Biophysics “Adriano Buzzati Traverso,” National Research Council, Naples, Italy
- Department of Chemistry and Biology, University of Salerno, Fisciano, Italy
| | - Antonio Baldini
- Institute of Genetics and Biophysics “Adriano Buzzati Traverso,” National Research Council, Naples, Italy
- University Federico II, Naples, Italy
- * E-mail:
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142
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The chromatin-remodeling enzymes BRG1 and CHD4 antagonistically regulate vascular Wnt signaling. Mol Cell Biol 2012; 32:1312-20. [PMID: 22290435 DOI: 10.1128/mcb.06222-11] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Canonical Wnt signaling plays an important role in embryonic and postnatal blood vessel development. We previously reported that the chromatin-remodeling enzyme BRG1 promotes vascular Wnt signaling. Vascular deletion of Brg1 results in aberrant yolk sac blood vessel morphology, which is rescued by pharmacological stimulation of Wnt signaling with lithium chloride (LiCl). We have now generated embryos lacking the chromatin-remodeling enzyme Chd4 in vascular endothelial cells. Unlike Brg1 mutants, Chd4 mutant embryos had normal yolk sac vascular morphology. However, concomitant deletion of Chd4 and Brg1 rescued vascular abnormalities seen in Brg1 mutant yolk sacs to the same extent as LiCl treatment. We hypothesized that Wnt signaling was upregulated in Chd4 mutant yolk sac vasculature. Indeed, we found that Chd4 deletion resulted in upregulation of the Wnt-responsive transcription factor Tcf7 and an increase in Wnt target gene expression in endothelial cells. Furthermore, we identified one Wnt target gene, Pitx2, that was downregulated in Brg1 mutant endothelial cells but was rescued following LiCl treatment and in Brg1 Chd4 double mutant vasculature, suggesting that PITX2 helps to mediate the restoration of yolk sac vascular remodeling under both conditions. We conclude that BRG1 and CHD4 antagonistically modulate Wnt signaling in developing yolk sac vessels to mediate normal vascular remodeling.
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143
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Epigenetic repression of cardiac progenitor gene expression by Ezh2 is required for postnatal cardiac homeostasis. Nat Genet 2012; 44:343-7. [PMID: 22267199 PMCID: PMC3288669 DOI: 10.1038/ng.1068] [Citation(s) in RCA: 202] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2011] [Accepted: 12/09/2011] [Indexed: 12/14/2022]
Abstract
Adult-onset diseases can be associated with in utero events, but mechanisms for this remain unknown1,2. The polycomb histone methyltransferase, Ezh2, stabilizes transcription by depositing repressive marks during development that persist into adulthood3–9, but its function in postnatal organ homeostasis is unknown. We show that Ezh2 stabilizes cardiac gene expression and prevents cardiac pathology by repressing the homeodomain transcription factor Six1, which functions in cardiac progenitors but is stably silenced upon cardiac differentiation10. Ezh2 deletion in cardiac progenitors caused postnatal myocardial pathology and destabilized cardiac gene expression with activation of Six1-dependent skeletal muscle genes. Six1 induced cardiomyocyte hypertrophy and skeletal muscle gene expression. Furthermore, genetically reducing Six1 levels rescued the pathology of Ezh2-deficient hearts. Thus, Ezh2-mediated repression of Six1 in differentiating cardiac progenitors is essential for stable postnatal heart gene expression and homeostasis. Our results suggest that epigenetic dysregulation in embryonic progenitor cells predisposes to adult disease and dysregulated stress responses.
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144
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Abstract
Transcription factors regulate formation and function of the heart, and perturbation of transcription factor expression and regulation disrupts normal heart structure and function. Multiple mechanisms regulate the level and locus-specific activity of transcription factors, including transcription, translation, subcellular localization, posttranslational modifications, and context-dependent interactions with other transcription factors, chromatin remodeling enzymes, and epigenetic regulators. The zinc finger transcription factor GATA4 is among the best-studied cardiac transcriptional factors. This review focuses on molecular mechanisms that regulate GATA4 transcriptional activity in the cardiovascular system, providing a framework to investigate and understand the molecular regulation of cardiac gene transcription by other transcription factors.
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145
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Wu JI. Diverse functions of ATP-dependent chromatin remodeling complexes in development and cancer. Acta Biochim Biophys Sin (Shanghai) 2012; 44:54-69. [PMID: 22194014 DOI: 10.1093/abbs/gmr099] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Mammalian SWI/SNF like Brg1/Brm associated factors (BAF) chromatin-remodeling complexes are able to use energy derived from adenosine triphosphate (ATP) hydrolysis to change chromatin structures and regulate nuclear processes such as transcription. BAF complexes contain multiple subunits and the diverse subunit compositions provide functional specificities to BAF complexes. In this review, we summarize the functions of BAF subunits during mammalian development and in progression of various cancers. The mechanisms underlying the functional diversity and specificities of BAF complexes will be discussed.
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Affiliation(s)
- Jiang I Wu
- Department of Physiology and Developmental Biology, University of Texas Southwestern Medical Center at Dallas, 75390-9133, USA.
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146
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Abstract
The cardiovascular system is broadly composed of the heart, which pumps blood, and the blood vessels, which carry blood to and from tissues of the body. Heart malformations are the most serious common birth defect, affecting at least 2% of newborns and leading to significant morbidity and mortality. Severe heart malformations cause heart failure in fetuses, infants, and children, whereas milder heart defects may not trigger significant heart dysfunction until early or midadulthood. Severe vasculogenesis or angiogenesis defects in embryos are incompatible with life, and anomalous arterial patterning may cause vascular aberrancies that often require surgical treatment. It is therefore important to understand the underlying mechanisms that control cardiovascular development. Understanding developmental mechanisms will also help us design better strategies to regenerate cardiovascular tissues for therapeutic purposes. An important mechanism regulating genes involves the modification of chromatin, the higher-order structure in which DNA is packaged. Recent studies have greatly expanded our understanding of the regulation of cardiovascular development at the chromatin level, including the remodeling of chromatin and the modification of histones. Chromatin-level regulation integrates multiple inputs and coordinates broad gene expression programs. Thus, understanding chromatin-level regulation will allow for a better appreciation of gene regulation as a whole and may set a fundamental basis for cardiovascular disease. This review focuses on how chromatin-remodeling and histone-modifying factors regulate gene expression to control cardiovascular development.
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Affiliation(s)
- Ching-Pin Chang
- Division of Cardiovascular Medicine, Department of Medicine, Stanford University School of Medicine, Stanford, California 94305, USA.
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147
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Bruneau BG. Atrial natriuretic factor in the developing heart: a signpost for cardiac morphogenesis. Can J Physiol Pharmacol 2011; 89:533-7. [PMID: 21806510 DOI: 10.1139/y11-051] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The developing heart forms during the early stages of embryogenesis, and misregulated heart development results in congenital heart defects (CHDs). To understand the molecular basis of CHDs, a deep understanding of the morphological and genetic basis of heart development is necessary. Atrial Natriuretic Factor (ANF) is an important and extremely sensitive marker for specific regions of the developing heart, as well as for disturbances in the patterning of the heart. This review summarizes the dynamic expression of ANF in the developing heart and its usefulness in understanding the early molecular defects underlying CHDs.
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Affiliation(s)
- Benoit G Bruneau
- Gladstone Institute of Cardiovascular Disease, 1650 Owens Street, San Francisco, CA 94158, USA.
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148
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Lou X, Deshwar AR, Crump JG, Scott IC. Smarcd3b and Gata5 promote a cardiac progenitor fate in the zebrafish embryo. Development 2011; 138:3113-23. [DOI: 10.1242/dev.064279] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Development of the heart requires recruitment of cardiovascular progenitor cells (CPCs) to the future heart-forming region. CPCs are the building blocks of the heart, and have the potential to form all the major cardiac lineages. However, little is known regarding what regulates CPC fate and behavior. Activity of GATA4, SMARCD3 and TBX5 – the `cardiac BAF' (cBAF) complex, can promote myocardial differentiation in embryonic mouse mesoderm. Here, we exploit the advantages of the zebrafish embryo to gain mechanistic understanding of cBAF activity. Overexpression of smarcd3b and gata5 in zebrafish results in an enlarged heart, whereas combinatorial loss of cBAF components inhibits cardiac differentiation. In transplantation experiments, cBAF acts cell autonomously to promote cardiac fate. Remarkably, cells overexpressing cBAF migrate to the developing heart and differentiate as cardiomyocytes, endocardium and smooth muscle. This is observed even in host embryos that lack endoderm or cardiac mesoderm. Our results reveal an evolutionarily conserved role for cBAF activity in cardiac differentiation. Importantly, they demonstrate that Smarcd3b and Gata5 can induce a primitive, CPC-like state.
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Affiliation(s)
- Xin Lou
- Program in Development and Stem Cell Biology, The Hospital for Sick Children, Toronto, ON M5G 1L7, Canada
| | - Ashish R. Deshwar
- Program in Development and Stem Cell Biology, The Hospital for Sick Children, Toronto, ON M5G 1L7, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - J. Gage Crump
- Broad CIRM Center, University of Southern California Keck School of Medicine, Los Angeles, CA 90089, USA
| | - Ian C. Scott
- Program in Development and Stem Cell Biology, The Hospital for Sick Children, Toronto, ON M5G 1L7, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
- Heart and Stroke/Richard Lewar Centre of Excellence, University of Toronto, Toronto, ON M5S 3E2, Canada
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149
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Abstract
Chromatin modifications are integral elements of chromosome structure and its function and the vasculature depends on tissue-specific genome regulation for its development. A general concept for the de-regulation of chromatin modifications in cardiac and vascular disease is also emerging. The recognition that metabolic memory contributes to disease persistence highlights the benefit of early and aggressive treatment. As for the importance of memory, we do know that good metabolic control delays the onset of long-term diabetic complications. There are striking parallels between the timing of disease and the development of complications. Landmark multicenter clinical trials on diabetes patients have popularized the concept that glucose is also a demonstrable determinant for the development of complications, indicating the prolonged benefit of intensive therapy and the lasting damage of conventional therapy. Each cell type experiences thousands of modifications to the epigenome in response to environmental changes it is exposed to. Therefore, history is neither lost nor forgotten and previous experiences and exposure may form future memories. There is now a strong resurgence in research trying to understand gene-environment interactions and to determine what commits specific vascular cell types to specific memories. Recent insights show that cardiac gene expression is distinguished by specific chromatin remodeling events and histone modifications that are associated with heart disease.
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Affiliation(s)
- Assam El-Osta
- Epigenetics in Human Health and Disease, Baker IDI Heart and Diabetes Institute, Melbourne, VIC, Australia.
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150
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van Weerd JH, Koshiba-Takeuchi K, Kwon C, Takeuchi JK. Epigenetic factors and cardiac development. Cardiovasc Res 2011; 91:203-11. [PMID: 21606181 DOI: 10.1093/cvr/cvr138] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Congenital heart malformations remain the leading cause of death related to birth defects. Recent advances in developmental and regenerative cardiology have shed light on a mechanistic understanding of heart development that is controlled by a transcriptional network of genetic and epigenetic factors. This article reviews the roles of chromatin remodelling factors important for cardiac development with the current knowledge of cardiac morphogenesis, regeneration, and direct cardiac differentiation. In the last 5 years, critical roles of epigenetic factors have been revealed in the cardiac research field.
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Affiliation(s)
- Jan Hendrick van Weerd
- Cardiovascular Regeneration, Institute of Molecular and Cellular Biosciences, University of Tokyo, Tokyo, Japan
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