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Liu Y, Jin X, Ye Y, Xu Z, Du Z, Hong H, Yu H, Lin H, Huang X, Sun H. Emerging disinfection byproducts 3-bromine carbazole induces cardiac developmental toxicity via aryl hydrocarbon receptor activation in zebrafish larvae. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 346:123609. [PMID: 38395134 DOI: 10.1016/j.envpol.2024.123609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 02/05/2024] [Accepted: 02/17/2024] [Indexed: 02/25/2024]
Abstract
3-bromine carbazole (3-BCZ) represents a group of emerging aromatic disinfection byproducts (DBP) detected in drinking water; however, limited information is available regarding its potential cardiotoxicity. To assess its impacts, zebrafish embryos were exposed to 0, 0.06, 0.14, 0.29, 0.58, 1.44 or 2.88 mg/L of 3-BCZ for 120 h post fertilization (hpf). Our results revealed that ≥1.44 mg/L 3-BCZ exposure induced a higher incidence of heart malformation and an elevated pericardial area in zebrafish larvae; it also decreased the number of cardiac muscle cells and thins the walls of the ventricle and atrium while increasing cardiac output and impeding cardiac looping. Furthermore, 3-BCZ exposure also exhibited significant effects on the transcriptional levels of genes related to both cardiac development (nkx2.5, vmhc, gata4, tbx5, tbx2b, bmp4, bmp10, and bmp2b) and cardiac function (cacna1ab, cacna1da, atp2a1l, atp1b2b, atp1a3b, and tnnc1a). Notably, N-acetyl-L-cysteine, a reactive oxygen species scavenger, may alleviate the failure of cardiac looping induced by 3-BCZ but not the associated cardiac dysfunction or malformation; conversely, the aryl hydrocarbon receptor agonist CH131229 can completely eliminate the cardiotoxicity caused by 3-BCZ. This study provides new evidence for potential risks associated with ingesting 3-BCZ as well as revealing underlying mechanisms responsible for its cardiotoxic effects on zebrafish embryos.
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Affiliation(s)
- Yingying Liu
- Key Laboratory of Watershed Earth Surface Processes and Ecological Security, College of Geography and Environmental Science, Zhejiang Normal University, Jinhua, Zhejiang, 321004, PR China
| | - Xudong Jin
- Key Laboratory of Watershed Earth Surface Processes and Ecological Security, College of Geography and Environmental Science, Zhejiang Normal University, Jinhua, Zhejiang, 321004, PR China
| | - Yanan Ye
- Key Laboratory of Watershed Earth Surface Processes and Ecological Security, College of Geography and Environmental Science, Zhejiang Normal University, Jinhua, Zhejiang, 321004, PR China
| | - Zeqiong Xu
- Key Laboratory of Watershed Earth Surface Processes and Ecological Security, College of Geography and Environmental Science, Zhejiang Normal University, Jinhua, Zhejiang, 321004, PR China
| | - Zhongkun Du
- College of Resources and Environment, Shandong Agricultural University, Key Laboratory of Agricultural Environment in Universities of Shandong, 61 Daizong Road, Taian, 271018, PR China
| | - Huachang Hong
- Key Laboratory of Watershed Earth Surface Processes and Ecological Security, College of Geography and Environmental Science, Zhejiang Normal University, Jinhua, Zhejiang, 321004, PR China
| | - Haiying Yu
- Key Laboratory of Watershed Earth Surface Processes and Ecological Security, College of Geography and Environmental Science, Zhejiang Normal University, Jinhua, Zhejiang, 321004, PR China
| | - Hongjun Lin
- Key Laboratory of Watershed Earth Surface Processes and Ecological Security, College of Geography and Environmental Science, Zhejiang Normal University, Jinhua, Zhejiang, 321004, PR China
| | - Xianfeng Huang
- National and Local Joint Engineering Research Center for Ecological Treatment Technology of Urban Water Pollution, College of Life and Environmental Science, Wenzhou University, Wenzhou, 325035, PR China
| | - Hongjie Sun
- Key Laboratory of Watershed Earth Surface Processes and Ecological Security, College of Geography and Environmental Science, Zhejiang Normal University, Jinhua, Zhejiang, 321004, PR China.
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2
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Luo Q, Ai L, Tang S, Zhang H, Ma J, Xiao X, Zhong K, Tian G, Cheng B, Xiong C, Chen X, Lu H. Developmental and cardiac toxicity assessment of Ethyl 3-(N-butylacetamido) propanoate (EBAAP) in zebrafish embryos. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2023; 261:106572. [PMID: 37307698 DOI: 10.1016/j.aquatox.2023.106572] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2023] [Revised: 05/09/2023] [Accepted: 05/11/2023] [Indexed: 06/14/2023]
Abstract
Ethyl 3-(N-butylacetamido) propanoate (EBAAP) is one of the most widely used mosquito repellents worldwide, and is also commonly used to produce cosmetics. Residues have recently been detected in surface and groundwater in many countries, and their potential to harm the environment is unknown. Therefore, more studies are needed to fully assess the toxicity of EBAAP. This is the first investigation into the developmental toxicity and cardiotoxicity of EBAAP on zebrafish embryos. EBAAP was toxic to zebrafish, with a lethal concentration 50 (LC50) of 140 mg/L at 72 hours post fertilization (hpf). EBAAP exposure also reduced body length, slowed the yolk absorption rate, induced spinal curvature and pericardial edema, decreased heart rate, promoted linear lengthening of the heart, and diminished cardiac pumping ability. The expression of heart developmental-related genes (nkx2.5, myh6, tbx5a, vmhc, gata4, tbx2b) was dysregulated, intracellular oxidative stress increased significantly, the activities of catalase (CAT) and superoxide dismutase (SOD) decreased, and malondialdehyde (MDA) content increased significantly. The expression of apoptosis-related genes (bax/bcl2, p53, caspase9, caspase3) was significantly upregulated. In conclusion, EBAAP induced abnormal morphology and heart defects during the early stages of zebrafish embryo development by potentially inducing the generation and accumulation of reactive oxygen species (ROS) in vivo and activating the oxidative stress response. These events dysregulate the expression of several genes and activate endogenous apoptosis pathways, eventually leading to developmental disorders and heart defects.
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Affiliation(s)
- Qiang Luo
- Ganzhou Key Laboratory for Drug Screening and Discovery, School of Geography and Environmental Engineering, Gannan Normal University, Ganzhou, 341000, Jiangxi, China
| | - Liping Ai
- Ganzhou Key Laboratory for Drug Screening and Discovery, School of Geography and Environmental Engineering, Gannan Normal University, Ganzhou, 341000, Jiangxi, China
| | - Shuqiong Tang
- Ganzhou Key Laboratory for Drug Screening and Discovery, School of Geography and Environmental Engineering, Gannan Normal University, Ganzhou, 341000, Jiangxi, China
| | - Hua Zhang
- Ganzhou Key Laboratory for Drug Screening and Discovery, School of Geography and Environmental Engineering, Gannan Normal University, Ganzhou, 341000, Jiangxi, China
| | - Jinze Ma
- Ganzhou Key Laboratory for Drug Screening and Discovery, School of Geography and Environmental Engineering, Gannan Normal University, Ganzhou, 341000, Jiangxi, China
| | - Xiaoping Xiao
- Ganzhou Key Laboratory for Drug Screening and Discovery, School of Geography and Environmental Engineering, Gannan Normal University, Ganzhou, 341000, Jiangxi, China; Provincial Key Laboratory of Low-Carbon Solid Waste Recycling, Gannan Normal University, Ganzhou, 341000, Jiangxi, China
| | - Keyuan Zhong
- Ganzhou Key Laboratory for Drug Screening and Discovery, School of Geography and Environmental Engineering, Gannan Normal University, Ganzhou, 341000, Jiangxi, China; Provincial Key Laboratory of Low-Carbon Solid Waste Recycling, Gannan Normal University, Ganzhou, 341000, Jiangxi, China
| | - Guiyou Tian
- Ganzhou Key Laboratory for Drug Screening and Discovery, School of Geography and Environmental Engineering, Gannan Normal University, Ganzhou, 341000, Jiangxi, China
| | - Bo Cheng
- Ganzhou Key Laboratory for Drug Screening and Discovery, School of Geography and Environmental Engineering, Gannan Normal University, Ganzhou, 341000, Jiangxi, China
| | - Cong Xiong
- Ganzhou Key Laboratory for Drug Screening and Discovery, School of Geography and Environmental Engineering, Gannan Normal University, Ganzhou, 341000, Jiangxi, China
| | - Xiaobei Chen
- Ganzhou Key Laboratory for Drug Screening and Discovery, School of Geography and Environmental Engineering, Gannan Normal University, Ganzhou, 341000, Jiangxi, China
| | - Huiqiang Lu
- Ganzhou Key Laboratory for Drug Screening and Discovery, School of Geography and Environmental Engineering, Gannan Normal University, Ganzhou, 341000, Jiangxi, China.
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3
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Duan F, Li H, Lu H. In vivo and molecular docking studies of the pathological mechanism underlying adriamycin cardiotoxicity. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2023; 256:114778. [PMID: 36989556 DOI: 10.1016/j.ecoenv.2023.114778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 02/19/2023] [Accepted: 03/12/2023] [Indexed: 06/19/2023]
Abstract
Adriamycin (ADR), one of the most effective broad-spectrum antitumor chemotherapeutic agents in clinical practice, is used to treat solid tumors as well as hematological malignancies in adults and children. However, long-term ADR use causes several adverse reactions, including time- and dose-dependent cardiotoxicity, which limit its clinical application. In addition, the mechanism by which ADR induces cardiotoxicity remains unclear. Therefore, we used zebrafish as animal models to evaluate ADR toxicity during embryonic heart development owing to the similarity of this process in zebrafish to that in humans. Exposure of zebrafish embryos to 1.25, 2.5, and 5 mg/L ADR induced abnormal embryonic development, with the occurrence of cardiac malformations, pericardial edema, decreased movement speed and activity, and increased distance between the venous sinus and the arterial bulb (SV-BA). ADR exposure induced dysregulated cardiogenesis during the precardiac mesoderm formation period. We also observed irregular expression of cardiac-related genes, an upregulation of apoptotic gene expression, and a dose-dependent increase in oxidative stress levels. Furthermore, oxidative stress-induced apoptosis exerted deleterious effects on cardiac development in zebrafish embryos, and treatment with astaxanthin (ATX) alleviated these heart defects. ADR- and Wnt pathway-related genes exhibited good energy and spatial matching, and ADR upregulated the Wnt signaling pathway in zebrafish. Moreover, IWR-1 effectively alleviated ADR-induced heart defects. In conclusion, we demonstrated that the toxic effects of ADR on cardiac development in zebrafish embryos could provide a theoretical basis for explaining the pathogenesis of ADR-induced cardiotoxicity, which occurs through the upregulation of oxidative stress and Wnt signaling pathway, as well as its prevention and treatment in humans. These findings will help develop effective treatment strategies to combat ADR-induced cardiotoxicity and broaden the application of ADR for clinical practice.
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Affiliation(s)
- Fangfang Duan
- Central Laboratory, The Affiliated Children's Hospital of Nanchang Medical College, Nanchang 330038, China
| | - Hong Li
- Central Laboratory, The Affiliated Children's Hospital of Nanchang Medical College, Nanchang 330038, China.
| | - Huiqiang Lu
- Affiliated Hospital of Jinggangshan University, Center for Clinical Medicine Research of Jinggangshan University, Ji'an 343000, China.
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Genetics and Molecular Basis of Congenital Heart Defects in Down Syndrome: Role of Extracellular Matrix Regulation. Int J Mol Sci 2023; 24:ijms24032918. [PMID: 36769235 PMCID: PMC9918028 DOI: 10.3390/ijms24032918] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 01/28/2023] [Accepted: 01/30/2023] [Indexed: 02/05/2023] Open
Abstract
Down syndrome (DS), a complex disorder that is caused by the trisomy of chromosome 21 (Hsa21), is a major cause of congenital heart defects (CHD). Interestingly, only about 50% of individuals with Hsa21 trisomy manifest CHD. Here we review the genetic basis of CHD in DS, focusing on genes that regulate extracellular matrix (ECM) organization. The overexpression of Hsa21 genes likely underlies the molecular mechanisms that contribute to CHD, even though the genes responsible for CHD could only be located in a critical region of Hsa21. A role in causing CHD has been attributed not only to protein-coding Hsa21 genes, but also to genes on other chromosomes, as well as miRNAs and lncRNAs. It is likely that the contribution of more than one gene is required, and that the overexpression of Hsa21 genes acts in combination with other genetic events, such as specific mutations or polymorphisms, amplifying their effect. Moreover, a key function in determining alterations in cardiac morphogenesis might be played by ECM. A large number of genes encoding ECM proteins are overexpressed in trisomic human fetal hearts, and many of them appear to be under the control of a Hsa21 gene, the RUNX1 transcription factor.
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Venegas-Zamora L, Bravo-Acuña F, Sigcho F, Gomez W, Bustamante-Salazar J, Pedrozo Z, Parra V. New Molecular and Organelle Alterations Linked to Down Syndrome Heart Disease. Front Genet 2022; 12:792231. [PMID: 35126461 PMCID: PMC8808411 DOI: 10.3389/fgene.2021.792231] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2021] [Accepted: 12/13/2021] [Indexed: 12/13/2022] Open
Abstract
Down syndrome (DS) is a genetic disorder caused by a trisomy of the human chromosome 21 (Hsa21). Overexpression of Hsa21 genes that encode proteins and non-coding RNAs (ncRNAs) can disrupt several cellular functions and biological processes, especially in the heart. Congenital heart defects (CHDs) are present in 45–50% of individuals with DS. Here, we describe the genetic background of this condition (Hsa21 and non-Hsa21 genes), including the role of ncRNAs, and the relevance of these new players in the study of the pathophysiology of DS heart diseases. Additionally, we discuss several distinct pathways in cardiomyocytes which help maintain a functional heart, but that might trigger hypertrophy and oxidative stress when altered. Moreover, we highlight the importance of investigating how mitochondrial and lysosomal dysfunction could eventually contribute to understanding impaired heart function and development in subjects with the Hsa21 trisomy. Altogether, this review focuses on the newest insights about the gene expression, molecular pathways, and organelle alterations involved in the cardiac phenotype of DS.
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Affiliation(s)
- Leslye Venegas-Zamora
- Advanced Center of Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas y Facultad de Medicina, Universidad de Chile, Santiago, Chile
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | - Francisco Bravo-Acuña
- Advanced Center of Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas y Facultad de Medicina, Universidad de Chile, Santiago, Chile
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | - Francisco Sigcho
- Advanced Center of Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas y Facultad de Medicina, Universidad de Chile, Santiago, Chile
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | - Wileidy Gomez
- Advanced Center of Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas y Facultad de Medicina, Universidad de Chile, Santiago, Chile
- Laboratory of Neuroprotection and Autophagy, Center for Integrative Biology, Faculty of Science, Universidad Mayor, Santiago, Chile
| | - José Bustamante-Salazar
- Advanced Center of Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas y Facultad de Medicina, Universidad de Chile, Santiago, Chile
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | - Zully Pedrozo
- Advanced Center of Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas y Facultad de Medicina, Universidad de Chile, Santiago, Chile
- Programa de Fisiología y Biofísica, ICBM, Facultad de Medicina, Universidad de Chile, Santiago, Chile
- Red para El Estudio de Enfermedades Cardiopulmonares de Alta Letalidad (REECPAL), Universidad de Chile, Santiago, Chile
- *Correspondence: Zully Pedrozo, ; Valentina Parra,
| | - Valentina Parra
- Advanced Center of Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas y Facultad de Medicina, Universidad de Chile, Santiago, Chile
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
- Red para El Estudio de Enfermedades Cardiopulmonares de Alta Letalidad (REECPAL), Universidad de Chile, Santiago, Chile
- *Correspondence: Zully Pedrozo, ; Valentina Parra,
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6
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Bühler A, Gahr BM, Park DD, Bertozzi A, Boos A, Dalvoy M, Pott A, Oswald F, Kovall RA, Kühn B, Weidinger G, Rottbauer W, Just S. Histone deacetylase 1 controls cardiomyocyte proliferation during embryonic heart development and cardiac regeneration in zebrafish. PLoS Genet 2021; 17:e1009890. [PMID: 34723970 PMCID: PMC8584950 DOI: 10.1371/journal.pgen.1009890] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 11/11/2021] [Accepted: 10/18/2021] [Indexed: 12/20/2022] Open
Abstract
In contrast to mammals, the zebrafish maintains its cardiomyocyte proliferation capacity throughout adulthood. However, neither the molecular mechanisms that orchestrate the proliferation of cardiomyocytes during developmental heart growth nor in the context of regeneration in the adult are sufficiently defined yet. We identified in a forward genetic N-ethyl-N-nitrosourea (ENU) mutagenesis screen the recessive, embryonic-lethal zebrafish mutant baldrian (bal), which shows severely impaired developmental heart growth due to diminished cardiomyocyte proliferation. By positional cloning, we identified a missense mutation in the zebrafish histone deacetylase 1 (hdac1) gene leading to severe protein instability and the loss of Hdac1 function in vivo. Hdac1 inhibition significantly reduces cardiomyocyte proliferation, indicating a role of Hdac1 during developmental heart growth in zebrafish. To evaluate whether developmental and regenerative Hdac1-associated mechanisms of cardiomyocyte proliferation are conserved, we analyzed regenerative cardiomyocyte proliferation after Hdac1 inhibition at the wound border zone in cryoinjured adult zebrafish hearts and we found that Hdac1 is also essential to orchestrate regenerative cardiomyocyte proliferation in the adult vertebrate heart. In summary, our findings suggest an important and conserved role of Histone deacetylase 1 (Hdac1) in developmental and adult regenerative cardiomyocyte proliferation in the vertebrate heart. Heart disease is one of the most common causes of death in all developed countries. While zebrafish cardiomyocytes are able to proliferate throughout adulthood, mammalian cardiomyocytes lose this ability during early development, and therefore are not capable to replace and renew cardiomyocytes after injury. The underlying mechanisms of cardiomyocyte proliferation are still not completely resolved. Understanding how zebrafish cardiomyocytes preserve their proliferating state, would be a valuable information to foster cardiac regeneration, e.g. after myocardial infarction in patients. Knowledge of the signaling pathways that need to be activated, or deactivated in order to induce cardiomyocyte proliferation after acute or chronic injury will pave the way for the development of genetic and/or pharmacological treatment options. In an ENU-mutagenesis screen, we identified the zebrafish mutant baldrian, which shows reduced embryonic cardiomyocyte proliferation. As genetic cause of the observed phenotype, we identified a missense mutation in the hdac1 gene. By treatment of heart-injured adult fish with the HDAC1 inhibitor Mocetinostat, we were able to show a reduced rate of cardiomyocyte proliferation also in the adult zebrafish heart in vivo, suggesting a role of Hdac1 in embryonic heart growth and adult regenerative cardiomyocyte proliferation in zebrafish.
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Affiliation(s)
- Anja Bühler
- Molecular Cardiology, Department of Internal Medicine II, University of Ulm, Ulm, Germany
| | - Bernd M Gahr
- Molecular Cardiology, Department of Internal Medicine II, University of Ulm, Ulm, Germany
| | - Deung-Dae Park
- Molecular Cardiology, Department of Internal Medicine II, University of Ulm, Ulm, Germany
| | - Alberto Bertozzi
- Institute of Biochemistry and Molecular Biology, University of Ulm, Ulm, Germany
| | - Alena Boos
- Molecular Cardiology, Department of Internal Medicine II, University of Ulm, Ulm, Germany
| | - Mohankrishna Dalvoy
- Institute of Biochemistry and Molecular Biology, University of Ulm, Ulm, Germany
| | - Alexander Pott
- Molecular Cardiology, Department of Internal Medicine II, University of Ulm, Ulm, Germany.,Department of Internal Medicine II, University of Ulm, Ulm, Germany
| | - Franz Oswald
- Department of Internal Medicine I, University of Ulm, Ulm, Germany
| | - Rhett A Kovall
- Department of Molecular Genetics, Biochemistry and Microbiology, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
| | - Bernhard Kühn
- Department of Pediatrics, University of Pittsburgh, and Richard King Mellon Institute for Pediatric Research and Division of Pediatric Cardiology, Children's Hospital of Pittsburgh of UPMC, Pittsburgh, Pennsylvania, United States of America
| | - Gilbert Weidinger
- Institute of Biochemistry and Molecular Biology, University of Ulm, Ulm, Germany
| | | | - Steffen Just
- Molecular Cardiology, Department of Internal Medicine II, University of Ulm, Ulm, Germany
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Williams B, Friedenberg SG, Keene BW, Tou SP, DeFrancesco TC, Meurs KM. Use of whole genome analysis to identify shared genomic variants across breeds in canine mitral valve disease. Hum Genet 2021; 140:1563-1568. [PMID: 34176051 DOI: 10.1007/s00439-021-02297-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2021] [Accepted: 05/24/2021] [Indexed: 12/24/2022]
Abstract
Familial mitral valve prolapse in human beings has been associated with several genetic variants; however, in most cases, a known variant has not been identified. Dogs also have a naturally occurring form of familial mitral valve disease (MMVD) with similarities to the human disease. A shared genetic background and clinical phenotype of this disease in some dog breeds has indicated that the disease may share a common genetic cause. We evaluated DNA from 50 affected dogs from five different dog breeds in a whole genome sequencing approach to identify shared variants across and within breeds that could be associated with MMVD. No single causative genetic mutation was found from the 50 dogs with MMVD. Ten variants were identified in 37/50 dogs around and within the MED13L gene. These variants were no longer associated with MMVD when evaluated with a larger cohort including both affected and unaffected dogs. No high/moderate impact variants were identified in 10/10 miniature poodles, one was identified in 10/10 Yorkshire Terriers and 10/10 dachshunds, respectively, 14 were identified in 10/10 Miniature schnauzers, and 19 in 10/10 CKCS. Only one of these could be associated with the cardiac valve (Chr12:36801705, COL12A1; CKCS) but when evaluated in an additional 100 affected CKCS the variant was only identified in 84/100 affected dogs, perhaps indicating genetic heterogeneity in this disease. Our findings indicate that development of MMVD in the dog may be related to a combination of genetic and environmental factors that impact specific molecular pathways rather than a single shared genetic variant across or within breeds.
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Affiliation(s)
- Brian Williams
- Department of Veterinary Clinical Sciences, North Carolina State University, Raleigh, NC, 27607, USA
| | - Steven G Friedenberg
- Department of Veterinary Clinical Sciences, University of Minnesota, Saint Paul, MN, 55108, USA
| | - Bruce W Keene
- Department of Veterinary Clinical Sciences, North Carolina State University, Raleigh, NC, 27607, USA
| | - Sandy P Tou
- Department of Veterinary Clinical Sciences, North Carolina State University, Raleigh, NC, 27607, USA
| | - Teresa C DeFrancesco
- Department of Veterinary Clinical Sciences, North Carolina State University, Raleigh, NC, 27607, USA
| | - Kathryn M Meurs
- Department of Veterinary Clinical Sciences, North Carolina State University, Raleigh, NC, 27607, USA.
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Diofano F, Weinmann K, Schneider I, Thiessen KD, Rottbauer W, Just S. Genetic compensation prevents myopathy and heart failure in an in vivo model of Bag3 deficiency. PLoS Genet 2020; 16:e1009088. [PMID: 33137814 PMCID: PMC7605898 DOI: 10.1371/journal.pgen.1009088] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Accepted: 08/31/2020] [Indexed: 12/15/2022] Open
Abstract
Mutations in the molecular co-chaperone Bcl2-associated athanogene 3 (BAG3) are found to cause dilated cardiomyopathy (DCM), resulting in systolic dysfunction and heart failure, as well as myofibrillar myopathy (MFM), which is characterized by protein aggregation and myofibrillar disintegration in skeletal muscle cells. Here, we generated a CRISPR/Cas9-induced Bag3 knockout zebrafish line and found the complete preservation of heart and skeletal muscle structure and function during embryonic development, in contrast to morpholino-mediated knockdown of Bag3. Intriguingly, genetic compensation, a process of transcriptional adaptation which acts independent of protein feedback loops, was found to prevent heart and skeletal muscle damage in our Bag3 knockout model. Proteomic profiling and quantitative real-time PCR analyses identified Bag2, another member of the Bag protein family, significantly upregulated on a transcript and protein level in bag3-/- mutants. This implied that the decay of bag3 mutant mRNA in homozygous bag3-/- embryos caused the transcriptional upregulation of bag2 expression. We further demonstrated that morpholino-mediated knockdown of Bag2 in bag3-/- embryos evoked severe functional and structural heart and skeletal muscle defects, which are similar to Bag3 morphants. However, Bag2 knockdown in bag3+/+ or bag3+/- embryos did not result in (cardio-)myopathy. Finally, we found that inhibition of the nonsense-mediated mRNA decay (NMD) machinery by knockdown of upf1, an essential NMD factor, caused severe heart and skeletal muscle defects in bag3-/- mutants due to the blockade of transcriptional adaptation of bag2 expression. Our findings provide evidence that genetic compensation might vitally influence the penetrance of disease-causing bag3 mutations in vivo. One form of genetic compensation is described as transcriptional adaptation of gene expression triggered by deleterious gene mutations. Although the precise molecular mechanism that induces genetic compensation needs to be defined, it represents a powerful biological phenomenon that warrants genetic robustness. We find that antisense-mediated knockdown of Bag3 in zebrafish embryos causes heart failure and myopathy. By contrast, CRISPR/Cas9-induced depletion of Bag3 does not result in the abrogation of heart and skeletal muscle function in zebrafish embryos. We find here that transcriptional activation of the Bag family member bag2 is capable of restoring heart and skeletal muscle function in bag3 mutant embryos, whereas this compensatory mechanism is not present in the bag3 morphants. Furthermore, we show that nonsense-mediated decay of bag3 mRNA is the molecular trigger for the compensatory upregulation of bag2. Our study provides evidence that genetic compensation via transcriptional adaptation is a vital modulator of disease peculiarity and penetrance in bag3 mutant zebrafish and that this biological phenomenon might also be active in certain human BAG3 mutation carriers.
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MESH Headings
- Adaptor Proteins, Signal Transducing/deficiency
- Adaptor Proteins, Signal Transducing/genetics
- Adaptor Proteins, Signal Transducing/metabolism
- Animals
- Apoptosis/genetics
- Apoptosis Regulatory Proteins/deficiency
- Apoptosis Regulatory Proteins/genetics
- Apoptosis Regulatory Proteins/metabolism
- Cardiomyopathies/genetics
- Cardiomyopathies/metabolism
- Cardiomyopathies/pathology
- Cardiomyopathy, Dilated/genetics
- Cardiomyopathy, Dilated/metabolism
- Cardiomyopathy, Dilated/pathology
- Disease Models, Animal
- Heart Failure/genetics
- Heart Failure/metabolism
- Heart Failure/pathology
- Molecular Chaperones/genetics
- Molecular Chaperones/metabolism
- Muscle Fibers, Skeletal/metabolism
- Muscular Diseases/genetics
- Muscular Diseases/metabolism
- Muscular Diseases/pathology
- Mutation
- Myocardium/metabolism
- Myopathies, Structural, Congenital/metabolism
- Phenotype
- Proteomics
- Zebrafish
- Zebrafish Proteins/deficiency
- Zebrafish Proteins/genetics
- Zebrafish Proteins/metabolism
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Affiliation(s)
- Federica Diofano
- Molecular Cardiology, Department of Internal Medicine II, University of Ulm, Ulm, Germany
| | - Karolina Weinmann
- Molecular Cardiology, Department of Internal Medicine II, University of Ulm, Ulm, Germany
- Department of Internal Medicine II, University of Ulm, Ulm, Germany
| | - Isabelle Schneider
- Molecular Cardiology, Department of Internal Medicine II, University of Ulm, Ulm, Germany
| | - Kevin D. Thiessen
- Molecular Cardiology, Department of Internal Medicine II, University of Ulm, Ulm, Germany
| | | | - Steffen Just
- Molecular Cardiology, Department of Internal Medicine II, University of Ulm, Ulm, Germany
- * E-mail:
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9
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Liu L, Fei F, Zhang R, Wu F, Yang Q, Wang F, Sun S, Zhao H, Li Q, Wang L, Wang Y, Gui Y, Wang X. Combinatorial genetic replenishments in myocardial and outflow tract tissues restore heart function in tnnt2 mutant zebrafish. Biol Open 2019; 8:bio.046474. [PMID: 31796423 PMCID: PMC6918781 DOI: 10.1242/bio.046474] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Cardiac muscle troponin T (Tnnt2) mediates muscle contraction in response to calcium ion dynamics, and Tnnt2 mutations are associated with multiple types of cardiomyopathy. Here, we employed a zebrafish model to investigate the genetic replenishment strategies of using conditional and inducible promoters to rescue the deficiencies in the heart. tnnt2a mutations were induced in zebrafish via the CRISPR/Cas9 technique, and the mutants displayed heart arrest and dilated cardiomyopathy-like phenotypes. We first utilized the classic myocardial promoter of the myl7 and TetOn inducible system to restore tnnt2a expression in myocardial tissue in tnnt2a mutant zebrafish. However, this attempt failed to recover normal heart function and circulation, although heart pumping was partially restored. Further analyses via both RNA-seq and immunofluorescence indicated that Tnnt2a, which was also expressed in a novel group of myl7-negative smooth muscle cells on the outflow tract (OFT), was indispensably responsible for the normal mechanical dynamics of OFT. Lastly, tnnt2 expression induced by OFT cells in addition to the myocardial cells successfully rescued heart function and circulation in tnnt2a mutant zebrafish. Together, our results reveal the significance of OFT expression of Tnnt2 for cardiac function and demonstrate zebrafish larva as a powerful and convenient in vivo platform for studying cardiomyopathy and the relevant therapeutic strategies.
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Affiliation(s)
- Lian Liu
- Department of Cardiology, Children's Hospital of Fudan University, Shanghai 201102, China
| | - Fei Fei
- Cancer Metabolism Laboratory, Cancer Institute, Fudan University Shanghai Cancer Center, Shanghai 200032, China.,Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai 230002, China
| | - Ranran Zhang
- Department of Pediatrics, the Affiliated Hospital of Qingdao University, Qingdao, Shangdong 266003, China
| | - Fang Wu
- Department of Cardiology, Children's Hospital of Fudan University, Shanghai 201102, China
| | - Qian Yang
- Department of Cardiology, Children's Hospital of Fudan University, Shanghai 201102, China
| | - Feng Wang
- Department of Cardiology, Children's Hospital of Fudan University, Shanghai 201102, China
| | - Shaoyang Sun
- Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai 230002, China
| | - Hui Zhao
- Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai 200032, China
| | - Qiang Li
- Translational Medical Center for Development and Disease, Shanghai Key Laboratory of Birth Defect, Institute of Pediatrics, Children's Hospital of Fudan University, Shanghai 201102, China
| | - Lei Wang
- Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai 230002, China
| | - Youhua Wang
- Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai 200032, China
| | - Yonghao Gui
- Department of Cardiology, Children's Hospital of Fudan University, Shanghai 201102, China
| | - Xu Wang
- Cancer Metabolism Laboratory, Cancer Institute, Fudan University Shanghai Cancer Center, Shanghai 200032, China .,Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai 230002, China
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10
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Corrêa T, Feltes BC, Riegel M. Integrated analysis of the critical region 5p15.3-p15.2 associated with cri-du-chat syndrome. Genet Mol Biol 2019; 42:186-196. [PMID: 30985858 PMCID: PMC6687350 DOI: 10.1590/1678-4685-gmb-2018-0173] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Accepted: 07/29/2018] [Indexed: 11/21/2022] Open
Abstract
Cri-du-chat syndrome (CdCs) is one of the most common contiguous gene syndromes,
with an incidence of 1:15,000 to 1:50,000 live births. To better understand the
etiology of CdCs at the molecular level, we investigated theprotein–protein
interaction (PPI) network within the critical chromosomal region 5p15.3–p15.2
associated with CdCs using systemsbiology. Data were extracted from cytogenomic
findings from patients with CdCs. Based on clinical findings, molecular
characterization of chromosomal rearrangements, and systems biology data, we
explored possible genotype–phenotype correlations involving biological processes
connected with CdCs candidate genes. We identified biological processes
involving genes previously found to be associated with CdCs, such as
TERT, SLC6A3, and
CTDNND2, as well as novel candidate proteins with potential
contributions to CdCs phenotypes, including CCT5, TPPP, MED10, ADCY2, MTRR,
CEP72, NDUFS6, and MRPL36. Although further functional analyses of these
proteins are required, we identified candidate proteins for the development of
new multi-target genetic editing tools to study CdCs. Further research may
confirm those that are directly involved in the development of CdCs phenotypes
and improve our understanding of CdCs-associated molecular mechanisms.
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Affiliation(s)
- Thiago Corrêa
- Post-Graduate Program in Genetics and Molecular Biology, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Bruno César Feltes
- Institute of Informatics, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Mariluce Riegel
- Post-Graduate Program in Genetics and Molecular Biology, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.,Medical Genetics Service, Hospital de Clínicas de Porto Alegre, Porto Alegre, RS, Brazil
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11
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Song Y, Nahrgang J, Tollefsen KE. Transcriptomic analysis reveals dose-dependent modes of action of benzo(a)pyrene in polar cod (Boreogadus saida). THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 653:176-189. [PMID: 30408666 DOI: 10.1016/j.scitotenv.2018.10.261] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2018] [Revised: 10/15/2018] [Accepted: 10/19/2018] [Indexed: 06/08/2023]
Abstract
Polar cod (Boreogadus saida) has been used as a model Arctic species for hazard assessment of environmental stressors such as polycyclic aromatic hydrocarbons (PAHs). However, most of the PAH studies using polar cod rely on targeted biomarker-based analysis thus may not adequately address the complexity of the toxic mechanisms of the stressors. The present study was performed to develop a broad-content transcriptomic platform for polar cod and apply it for understanding the toxic mechanisms of a model PAH, benzo(a)pyrene (BaP). Hepatic transcriptional analysis using a combination of high-density polar cod oligonucleotide microarray and quantitative real-time RT-PCR was conducted to characterize the stress responses in polar cod after 14d repeated dietary exposure to 0.4 (Low) and 20.3 μg/g fish/feeding (High) BaP doses. Bile metabolic analysis was performed to identify the storage of a key BaP hepatic biotransformation product, 3-hydroxybenzo(a)pyrene (3-OH-BaP). The results clearly showed that 3-OH-BaP was detected in the bile of polar cod after both Low and High BaP exposure. Dose-dependent hepatic stress responses were identified, with Low BaP suppressing genes involved in the defense mechanisms and High BaP inducing genes associated with these pathways. The results suggested that activation of the aryl hydrocarbon receptor signaling, induction of oxidative stress, DNA damage and apoptosis were the common modes of action (MoA) of BaP between polar cod or other vertebrates, whereas induction of protein degradation and disturbance of mitochondrial functions were proposed as novel MoAs. Furthermore, conceptual toxicity pathways were proposed for BaP-mediated effects in Arctic fish. The present study has for the first time reported a transcriptome-wide analysis using a polar cod-specific microarray and suggested novel MoAs of BaP. The analytical tools, bioinformatics solutions and mechanistic knowledge generated by this study may facilitate mechanistically-based hazard assessment of environmental stressors in the Arctic using this important fish as a model species.
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Affiliation(s)
- You Song
- Norwegian Institute for Water Research (NIVA), Section of Ecotoxicology and Risk Assessment, Gaustadalléen 21, N-0349 Oslo, Norway.
| | - Jasmine Nahrgang
- UiT The Arctic University of Norway, Faculty of Biosciences, Fisheries and Economics, Dept. of Arctic and Marine Biology, N-9037 Tromsø, Norway
| | - Knut Erik Tollefsen
- Norwegian Institute for Water Research (NIVA), Section of Ecotoxicology and Risk Assessment, Gaustadalléen 21, N-0349 Oslo, Norway; Norwegian University of Life Sciences (NMBU), Faculty of Environmental Sciences and Natural Resource Management, Dept. for Environmental Sciences, Post box 5003, N-1432 Ås, Norway.
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12
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Kustermann M, Manta L, Paone C, Kustermann J, Lausser L, Wiesner C, Eichinger L, Clemen CS, Schröder R, Kestler HA, Sandri M, Rottbauer W, Just S. Loss of the novel Vcp (valosin containing protein) interactor Washc4 interferes with autophagy-mediated proteostasis in striated muscle and leads to myopathy in vivo. Autophagy 2018; 14:1911-1927. [PMID: 30010465 PMCID: PMC6152520 DOI: 10.1080/15548627.2018.1491491] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
VCP/p97 (valosin containing protein) is a key regulator of cellular proteostasis. It orchestrates protein turnover and quality control in vivo, processes fundamental for proper cell function. In humans, mutations in VCP lead to severe myo- and neuro-degenerative disorders such as inclusion body myopathy with Paget disease of the bone and frontotemporal dementia (IBMPFD), amyotrophic lateral sclerosis (ALS) or and hereditary spastic paraplegia (HSP). We analyzed here the in vivo role of Vcp and its novel interactor Washc4/Swip (WASH complex subunit 4) in the vertebrate model zebrafish (Danio rerio). We found that targeted inactivation of either Vcp or Washc4, led to progressive impairment of cardiac and skeletal muscle function, structure and cytoarchitecture without interfering with the differentiation of both organ systems. Notably, loss of Vcp resulted in compromised protein degradation via the proteasome and the macroautophagy/autophagy machinery, whereas Washc4 deficiency did not affect the function of the ubiquitin-proteasome system (UPS) but caused ER stress and interfered with autophagy function in vivo. In summary, our findings provide novel insights into the in vivo functions of Vcp and its novel interactor Washc4 and their particular and distinct roles during proteostasis in striated muscle cells.
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Affiliation(s)
- Monika Kustermann
- a Molecular Cardiology, Department of Internal Medicine II , University of Ulm , Ulm , Germany
| | - Linda Manta
- a Molecular Cardiology, Department of Internal Medicine II , University of Ulm , Ulm , Germany
| | - Christoph Paone
- a Molecular Cardiology, Department of Internal Medicine II , University of Ulm , Ulm , Germany
| | - Jochen Kustermann
- b Institute of Molecular Genetics and Cell Biology, Department of Biology , University of Ulm , Ulm , Germany
| | - Ludwig Lausser
- c Institute of Medical Systems Biology , University of Ulm , Ulm , Germany
| | - Cora Wiesner
- a Molecular Cardiology, Department of Internal Medicine II , University of Ulm , Ulm , Germany
| | - Ludwig Eichinger
- d Centre for Biochemistry, Institute of Biochemistry I, Medical Faculty , University of Cologne , Cologne , Germany
| | - Christoph S Clemen
- d Centre for Biochemistry, Institute of Biochemistry I, Medical Faculty , University of Cologne , Cologne , Germany.,e Department of Neurology, Heimer Institute for Muscle Research , University Hospital Bergmannsheil, Ruhr-University Bochum , Bochum , Germany
| | - Rolf Schröder
- f Institute of Neuropathology , University Hospital Erlangen , Erlangen , Germany
| | - Hans A Kestler
- c Institute of Medical Systems Biology , University of Ulm , Ulm , Germany
| | - Marco Sandri
- g Department of Biomedical Science, Venetian Institute of Molecular Medicine (VIMM) , University of Padova , Padova , Italy
| | - Wolfgang Rottbauer
- h Department of Internal Medicine II , University of Ulm , Ulm , Germany
| | - Steffen Just
- a Molecular Cardiology, Department of Internal Medicine II , University of Ulm , Ulm , Germany
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13
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Segert J, Schneider I, Berger IM, Rottbauer W, Just S. Mediator complex subunit Med12 regulates cardiac jelly development and AV valve formation in zebrafish. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2018; 138:20-31. [PMID: 30036562 DOI: 10.1016/j.pbiomolbio.2018.07.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Revised: 05/30/2018] [Accepted: 07/17/2018] [Indexed: 11/25/2022]
Abstract
The molecular mechanism essential for the formation of heart valves involves complex interactions of signaling molecules and transcription factors. The Mediator Complex (MC) functions as multi-subunit machinery to orchestrate gene transcription, especially for tissue-specific fine-tuning of transcriptional processes during development, also in the heart. Here, we analyzed the role of the MC subunit Med12 during atrioventricular canal (AVC) development and endocardial cushion formation, using the Med12-deficient zebrafish mutant trapped (tpd). Whereas primary heart formation was only slightly affected in tpd, we identified defects in AVC development and cardiac jelly formation. We found that although misexpression of bmp4 and versican in tpd hearts can be restored by overexpression of a modified version of the Sox9b transcription factor (harboring VP16 transactivation domain) that functions independent of its co-activator Med12, endocardial cushion development in tpd was not reconstituted. Interestingly, expression of tbx2b and its target hyaluronan synthase 2 (has2) - the synthase of hyaluronan (HA) in the heart - was absent in both uninjected and Sox9b-VP16 overexpressing tpd hearts. HA is a major ECM component of the cardiac jelly and required for endocardial cushion formation. Furthermore, we found secreted phosphoprotein 1 (spp1), an endocardial marker of activated AV endocardial cells, completely absent in tpd hearts, suggesting that crucial steps of the transformation of AV endocardial cells into endocardial cushions is blocked. We demonstrate that Med12 controls cardiac jelly formation Sox9-independently by regulating tbx2b and has2 expression and therefore the production of the glycosaminoglycan HA at the AVC to guarantee proper endocardial cushion development.
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Affiliation(s)
- Julia Segert
- Molecular Cardiology, Department of Internal Medicine II, University of Ulm, Ulm, Germany
| | - Isabelle Schneider
- Molecular Cardiology, Department of Internal Medicine II, University of Ulm, Ulm, Germany
| | - Ina M Berger
- Molecular Cardiology, Department of Internal Medicine II, University of Ulm, Ulm, Germany
| | | | - Steffen Just
- Molecular Cardiology, Department of Internal Medicine II, University of Ulm, Ulm, Germany.
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14
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Just S, Raphel L, Berger IM, Bühler A, Keßler M, Rottbauer W. Tbx20 Is an Essential Regulator of Embryonic Heart Growth in Zebrafish. PLoS One 2016; 11:e0167306. [PMID: 27907103 PMCID: PMC5132222 DOI: 10.1371/journal.pone.0167306] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Accepted: 11/13/2016] [Indexed: 01/06/2023] Open
Abstract
The molecular mechanisms that regulate cardiomyocyte proliferation during embryonic heart growth are not completely deciphered yet. In a forward genetic N-ethyl-N-nitrosourea (ENU) mutagenesis screen, we identified the recessive embryonic-lethal zebrafish mutant line weiches herz (whz). Homozygous mutant whz embryos display impaired heart growth due to diminished embryonic cardiomyocyte proliferation resulting in cardiac hypoplasia and weak cardiac contraction. By positional cloning, we found in whz mutant zebrafish a missense mutation within the T-box 20 (Tbx20) transcription factor gene leading to destabilization of Tbx20 protein. Morpholino-mediated knock-down of Tbx20 in wild-type zebrafish embryos phenocopies whz, indicating that the whz phenotype is due to loss of Tbx20 function, thereby leading to significantly reduced cardiomyocyte numbers by impaired proliferation of heart muscle cells. Ectopic overexpression of wild-type Tbx20 in whz mutant embryos restored cardiomyocyte proliferation and heart growth. Interestingly, ectopic overexpression of Tbx20 in wild-type zebrafish embryos resulted, similar to the situation in the embryonic mouse heart, in significantly reduced proliferation rates of ventricular cardiomyocytes, suggesting that Tbx20 activity needs to be tightly fine-tuned to guarantee regular cardiomyocyte proliferation and embryonic heart growth in vivo.
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Affiliation(s)
- Steffen Just
- Molecular Cardiology, Department of Medicine II, University of Ulm, Ulm, Germany
- * E-mail: (SJ); (WR)
| | - Linda Raphel
- Department of Medicine II, University of Ulm, Ulm, Germany
| | - Ina M. Berger
- Molecular Cardiology, Department of Medicine II, University of Ulm, Ulm, Germany
| | - Anja Bühler
- Molecular Cardiology, Department of Medicine II, University of Ulm, Ulm, Germany
| | - Mirjam Keßler
- Department of Medicine II, University of Ulm, Ulm, Germany
| | - Wolfgang Rottbauer
- Molecular Cardiology, Department of Medicine II, University of Ulm, Ulm, Germany
- Department of Medicine II, University of Ulm, Ulm, Germany
- * E-mail: (SJ); (WR)
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