1
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Buchwalter A. Intermediate, but not average: The unusual lives of the nuclear lamin proteins. Curr Opin Cell Biol 2023; 84:102220. [PMID: 37619289 DOI: 10.1016/j.ceb.2023.102220] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Revised: 07/26/2023] [Accepted: 07/27/2023] [Indexed: 08/26/2023]
Abstract
The nuclear lamins are polymeric intermediate filament proteins that scaffold the nucleus and organize the genome in nearly all eukaryotic cells. This review focuses on the dynamic regulation of lamin filaments through their biogenesis, assembly, disassembly, and degradation. The lamins are unusually long-lived proteins under homeostatic conditions, but their turnover can be induced in select contexts that are highlighted in this review. Finally, we discuss recent investigations into the influence of laminopathy-linked mutations on the assembly, folding, and stability of the nuclear lamins.
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Affiliation(s)
- Abigail Buchwalter
- Cardiovascular Research Institute and Department of Physiology, University of California, San Francisco, San Francisco, CA, USA; Chan Zuckerberg Biohub, San Francisco, CA, USA.
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2
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Wallace M, Zahr H, Perati S, Morsink CD, Johnson LE, Gacita AM, Lai S, Wallrath LL, Benjamin IJ, McNally EM, Kirby TJ, Lammerding J. Nuclear damage in LMNA mutant iPSC-derived cardiomyocytes is associated with impaired lamin localization to the nuclear envelope. Mol Biol Cell 2023; 34:mbcE21100527. [PMID: 37585285 PMCID: PMC10846625 DOI: 10.1091/mbc.e21-10-0527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 07/31/2023] [Accepted: 08/10/2023] [Indexed: 08/18/2023] Open
Abstract
The LMNA gene encodes the nuclear envelope proteins Lamins A and C, which comprise a major part of the nuclear lamina, provide mechanical support to the nucleus, and participate in diverse intracellular signaling. LMNA mutations give rise to a collection of diseases called laminopathies, including dilated cardiomyopathy (LMNA-DCM) and muscular dystrophies. Although nuclear deformities are a hallmark of LMNA-DCM, the role of nuclear abnormalities in the pathogenesis of LMNA-DCM remains incompletely understood. Using induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) from LMNA mutant patients and healthy controls, we show that LMNA mutant iPSC-CM nuclei have altered shape or increased size compared to healthy control iPSC-CM nuclei. The LMNA mutation exhibiting the most severe nuclear deformities, R249Q, additionally caused reduced nuclear stiffness and increased nuclear fragility. Importantly, for all cell lines, the degree of nuclear abnormalities corresponded to the degree of Lamin A/C and Lamin B1 mislocalization from the nuclear envelope. The mislocalization was likely due to altered assembly of Lamin A/C. Collectively, these results point to the importance of correct lamin assembly at the nuclear envelope in providing mechanical stability to the nucleus and suggest that defects in nuclear lamina organization may contribute to the nuclear and cellular dysfunction in LMNA-DCM.
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Affiliation(s)
- Melanie Wallace
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY 14853
- Weill Institute for Cell and Molecular Biology, Ithaca, NY 14853
| | - Hind Zahr
- Weill Institute for Cell and Molecular Biology, Ithaca, NY 14853
| | - Shriya Perati
- Weill Institute for Cell and Molecular Biology, Ithaca, NY 14853
| | - Chloé D. Morsink
- Department of Physiology, Amsterdam University Medical Centers, Amsterdam Cardiovascular Sciences, VU Medical Center, 1081 HZ Amsterdam, The Netherlands
| | | | - Anthony M. Gacita
- Center for Genetic Medicine, Feinberg School of Medicine, Northwestern Medicine, Chicago, IL 60611
| | - Shuping Lai
- Cardiovascular Center, Medical College of Wisconsin, Milwaukee, WI 53226
| | - Lori L. Wallrath
- Department of Biochemistry and Molecular Biology, University of Iowa, Iowa City, IA 52242
| | - Ivor J. Benjamin
- Cardiovascular Center, Medical College of Wisconsin, Milwaukee, WI 53226
| | - Elizabeth M. McNally
- Center for Genetic Medicine, Feinberg School of Medicine, Northwestern Medicine, Chicago, IL 60611
| | - Tyler J. Kirby
- Weill Institute for Cell and Molecular Biology, Ithaca, NY 14853
- Department of Physiology, Amsterdam University Medical Centers, Amsterdam Cardiovascular Sciences, VU Medical Center, 1081 HZ Amsterdam, The Netherlands
| | - Jan Lammerding
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY 14853
- Weill Institute for Cell and Molecular Biology, Ithaca, NY 14853
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3
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Pande S, Ghosh DK. Nuclear proteostasis imbalance in laminopathy-associated premature aging diseases. FASEB J 2023; 37:e23116. [PMID: 37498235 DOI: 10.1096/fj.202300878r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 06/15/2023] [Accepted: 07/13/2023] [Indexed: 07/28/2023]
Abstract
Laminopathies are a group of rare genetic disorders with heterogeneous clinical phenotypes such as premature aging, cardiomyopathy, lipodystrophy, muscular dystrophy, microcephaly, epilepsy, and so on. The cellular phenomena associated with laminopathy invariably show disruption of nucleoskeleton of lamina due to deregulated expression, localization, function, and interaction of mutant lamin proteins. Impaired spatial and temporal tethering of lamin proteins to the lamina or nucleoplasmic aggregation of lamins are the primary molecular events that can trigger nuclear proteotoxicity by modulating differential protein-protein interactions, sequestering quality control proteins, and initiating a cascade of abnormal post-translational modifications. Clearly, laminopathic cells exhibit moderate to high nuclear proteotoxicity, raising the question of whether an imbalance in nuclear proteostasis is involved in laminopathic diseases, particularly in diseases of early aging such as HGPS and laminopathy-associated premature aging. Here, we review nuclear proteostasis and its deregulation in the context of lamin proteins and laminopathies.
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Affiliation(s)
- Shruti Pande
- Department of Medical Genetics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, India
| | - Debasish Kumar Ghosh
- Enteric Disease Division, Department of Microbiology, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, India
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4
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Wang Y, Dobreva G. Epigenetics in LMNA-Related Cardiomyopathy. Cells 2023; 12:cells12050783. [PMID: 36899919 PMCID: PMC10001118 DOI: 10.3390/cells12050783] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Revised: 02/18/2023] [Accepted: 02/26/2023] [Indexed: 03/06/2023] Open
Abstract
Mutations in the gene for lamin A/C (LMNA) cause a diverse range of diseases known as laminopathies. LMNA-related cardiomyopathy is a common inherited heart disease and is highly penetrant with a poor prognosis. In the past years, numerous investigations using mouse models, stem cell technologies, and patient samples have characterized the phenotypic diversity caused by specific LMNA variants and contributed to understanding the molecular mechanisms underlying the pathogenesis of heart disease. As a component of the nuclear envelope, LMNA regulates nuclear mechanostability and function, chromatin organization, and gene transcription. This review will focus on the different cardiomyopathies caused by LMNA mutations, address the role of LMNA in chromatin organization and gene regulation, and discuss how these processes go awry in heart disease.
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Affiliation(s)
- Yinuo Wang
- Department of Cardiovascular Genomics and Epigenomics, European Center for Angioscience (ECAS), Medical Faculty Mannheim, Heidelberg University, 68167 Mannheim, Germany
- German Centre for Cardiovascular Research (DZHK), 68167 Mannheim, Germany
- Correspondence: (Y.W.); (G.D.)
| | - Gergana Dobreva
- Department of Cardiovascular Genomics and Epigenomics, European Center for Angioscience (ECAS), Medical Faculty Mannheim, Heidelberg University, 68167 Mannheim, Germany
- German Centre for Cardiovascular Research (DZHK), 68167 Mannheim, Germany
- Correspondence: (Y.W.); (G.D.)
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5
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West G, Turunen M, Aalto A, Virtanen L, Li SP, Heliö T, Meinander A, Taimen P. A heterozygous p.S143P mutation in LMNA associates with proteasome dysfunction and enhanced autophagy-mediated degradation of mutant lamins A and C. Front Cell Dev Biol 2022; 10:932983. [PMID: 36111332 PMCID: PMC9468711 DOI: 10.3389/fcell.2022.932983] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Accepted: 07/27/2022] [Indexed: 01/09/2023] Open
Abstract
Lamins A and C are nuclear intermediate filament proteins that form a proteinaceous meshwork called lamina beneath the inner nuclear membrane. Mutations in the LMNA gene encoding lamins A and C cause a heterogenous group of inherited degenerative diseases known as laminopathies. Previous studies have revealed altered cell signaling pathways in lamin-mutant patient cells, but little is known about the fate of mutant lamins A and C within the cells. Here, we analyzed the turnover of lamins A and C in cells derived from a dilated cardiomyopathy patient with a heterozygous p.S143P mutation in LMNA. We found that transcriptional activation and mRNA levels of LMNA are increased in the primary patient fibroblasts, but the protein levels of lamins A and C remain equal in control and patient cells because of a meticulous interplay between autophagy and the ubiquitin-proteasome system (UPS). Both endogenous and ectopic expression of p.S143P lamins A and C cause significantly reduced activity of UPS and an accumulation of K48-ubiquitin chains in the nucleus. Furthermore, K48-ubiquitinated lamins A and C are degraded by compensatory enhanced autophagy, as shown by increased autophagosome formation and binding of lamins A and C to microtubule-associated protein 1A/1B-light chain 3. Finally, chaperone 4-PBA augmented protein degradation by restoring UPS activity as well as autophagy in the patient cells. In summary, our results suggest that the p.S143P-mutant lamins A and C have overloading and deleterious effects on protein degradation machinery and pharmacological interventions with compounds enhancing protein degradation may be beneficial for cell homeostasis.
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Affiliation(s)
- Gun West
- Institute of Biomedicine and FICAN West Cancer Centre, University of Turku, Turku, Finland,InFLAMES Research Flagship Center, University of Turku and Åbo Akademi University, Turku, Finland
| | - Minttu Turunen
- Institute of Biomedicine and FICAN West Cancer Centre, University of Turku, Turku, Finland,InFLAMES Research Flagship Center, University of Turku and Åbo Akademi University, Turku, Finland
| | - Anna Aalto
- InFLAMES Research Flagship Center, University of Turku and Åbo Akademi University, Turku, Finland,Faculty of Science and Engineering, Åbo Akademi University, Turku, Finland
| | - Laura Virtanen
- Institute of Biomedicine and FICAN West Cancer Centre, University of Turku, Turku, Finland,InFLAMES Research Flagship Center, University of Turku and Åbo Akademi University, Turku, Finland
| | - Song-Ping Li
- Institute of Biomedicine and FICAN West Cancer Centre, University of Turku, Turku, Finland,InFLAMES Research Flagship Center, University of Turku and Åbo Akademi University, Turku, Finland
| | - Tiina Heliö
- Heart and Lung Center Helsinki University Hospital and University of Helsinki, Helsinki, Finland
| | - Annika Meinander
- InFLAMES Research Flagship Center, University of Turku and Åbo Akademi University, Turku, Finland,Faculty of Science and Engineering, Åbo Akademi University, Turku, Finland
| | - Pekka Taimen
- Institute of Biomedicine and FICAN West Cancer Centre, University of Turku, Turku, Finland,InFLAMES Research Flagship Center, University of Turku and Åbo Akademi University, Turku, Finland,Department of Pathology, Laboratory Division, Turku University Hospital, Turku, Finland,*Correspondence: Pekka Taimen,
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6
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Preclinical Advances of Therapies for Laminopathies. J Clin Med 2021; 10:jcm10214834. [PMID: 34768351 PMCID: PMC8584472 DOI: 10.3390/jcm10214834] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 10/19/2021] [Accepted: 10/19/2021] [Indexed: 11/29/2022] Open
Abstract
Laminopathies are a group of rare disorders due to mutation in LMNA gene. Depending on the mutation, they may affect striated muscles, adipose tissues, nerves or are multisystemic with various accelerated ageing syndromes. Although the diverse pathomechanisms responsible for laminopathies are not fully understood, several therapeutic approaches have been evaluated in patient cells or animal models, ranging from gene therapies to cell and drug therapies. This review is focused on these therapies with a strong focus on striated muscle laminopathies and premature ageing syndromes.
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7
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Abstract
PURPOSE OF REVIEW The purpose of this review is to provide an update on lamin A/C (LMNA)-related cardiomyopathy and discuss the current recommendations and progress in the management of this disease. LMNA-related cardiomyopathy, an inherited autosomal dominant disease, is one of the most common causes of dilated cardiomyopathy and is characterized by steady progression toward heart failure and high risks of arrhythmias and sudden cardiac death. RECENT FINDINGS We discuss recent advances in the understanding of the molecular mechanisms of the disease including altered cell biomechanics, which may represent novel therapeutic targets to advance the current management approach, which relies on standard heart failure recommendations. Future therapeutic approaches include repurposed molecularly directed drugs, siRNA-based gene silencing, and genome editing. LMNA-related cardiomyopathy is the focus of active in vitro and in vivo research, which is expected to generate novel biomarkers and identify new therapeutic targets. LMNA-related cardiomyopathy trials are currently underway.
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8
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Bianchi A, Manti PG, Lucini F, Lanzuolo C. Mechanotransduction, nuclear architecture and epigenetics in Emery Dreifuss Muscular Dystrophy: tous pour un, un pour tous. Nucleus 2019; 9:276-290. [PMID: 29619865 PMCID: PMC5973142 DOI: 10.1080/19491034.2018.1460044] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The alteration of the several roles that Lamin A/C plays in the mammalian cell leads to a broad spectrum of pathologies that – all together – are named laminopathies. Among those, the Emery Dreifuss Muscular Dystrophy (EDMD) is of particular interest as, despite the several known mutations of Lamin A/C, the genotype–phenotype correlation still remains poorly understood; this suggests that the epigenetic background of patients might play an important role during the time course of the disease. Historically, both a mechanical role of Lamin A/C and a regulative one have been suggested as the driving force of laminopathies; however, those two hypotheses are not mutually exclusive. Recent scientific evidence shows that Lamin A/C sustains the correct gene expression at the epigenetic level thanks to the Lamina Associated Domains (LADs) reorganization and the crosstalk with the Polycomb Group of Proteins (PcG). Furthermore, the PcG-dependent histone mark H3K27me3 increases under mechanical stress, finally pointing out the link between the mechano-properties of the nuclear lamina and epigenetics. Here, we summarize the emerging mechanisms that could explain the high variability seen in Emery Dreifuss muscular dystrophy.
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Affiliation(s)
- Andrea Bianchi
- a CNR Institute of Cell Biology and Neurobiology, Istituto di Ricovero e Cura a Carattere Scientifico Fondazione Santa Lucia , Rome , Italy.,b Istituto Nazionale Genetica Molecolare Romeo ed Enrica Invernizzi , Milan , Italy
| | | | - Federica Lucini
- b Istituto Nazionale Genetica Molecolare Romeo ed Enrica Invernizzi , Milan , Italy
| | - Chiara Lanzuolo
- a CNR Institute of Cell Biology and Neurobiology, Istituto di Ricovero e Cura a Carattere Scientifico Fondazione Santa Lucia , Rome , Italy.,b Istituto Nazionale Genetica Molecolare Romeo ed Enrica Invernizzi , Milan , Italy.,c Istituto di Ricovero e Cura a Carattere Scientifico Fondazione Santa Lucia , Rome , Italy
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9
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Vignier N, Chatzifrangkeskou M, Morales Rodriguez B, Mericskay M, Mougenot N, Wahbi K, Bonne G, Muchir A. Rescue of biosynthesis of nicotinamide adenine dinucleotide protects the heart in cardiomyopathy caused by lamin A/C gene mutation. Hum Mol Genet 2019; 27:3870-3880. [PMID: 30053027 DOI: 10.1093/hmg/ddy278] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Accepted: 07/20/2018] [Indexed: 01/07/2023] Open
Abstract
Cardiomyopathy caused by lamin A/C gene (LMNA) mutations (hereafter referred as LMNA cardiomyopathy) is an anatomic and pathologic condition associated with muscle and electrical dysfunction of the heart, often leading to heart failure-related disability. There is currently no specific therapy available for patients that target the molecular pathophysiology of LMNA cardiomyopathy. Recent studies suggested that nicotinamide adenine dinucleotide (NAD+) cellular content could be a critical determinant for heart function. Biosynthesis of NAD+ from vitamin B3 (known as salvage pathways) is the primary source of NAD+. We showed here that NAD+ salvage pathway was altered in the heart of mouse and human carrying LMNA mutation, leading to an alteration of one of NAD+ co-substrate enzymes, PARP-1. Oral administration of nicotinamide riboside, a natural NAD+ precursor and a pyridine-nucleoside form of vitamin B3, leads to a marked improvement of the NAD+ cellular content, an increase of PARylation of cardiac proteins and an improvement of left ventricular structure and function in a model of LMNA cardiomyopathy. Collectively, our results provide mechanistic and therapeutic insights into dilated cardiomyopathy caused by LMNA mutations.
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Affiliation(s)
- Nicolas Vignier
- Sorbonne Université, UPMC Paris 06, INSERM UMRS974, Center of Research in Myology, Institut de Myologie, Paris, France
| | - Maria Chatzifrangkeskou
- Sorbonne Université, UPMC Paris 06, INSERM UMRS974, Center of Research in Myology, Institut de Myologie, Paris, France
| | - Blanca Morales Rodriguez
- Sorbonne Université, UPMC Paris 06, INSERM UMRS974, Center of Research in Myology, Institut de Myologie, Paris, France
| | - Mathias Mericskay
- INSERM UMR-S 1180 - LabEx LERMIT - DHU TORINO, Institut Paris-Saclay d'Innovation Therapeutique (IPSIT-US31-UMS3679), Faculty of Pharmacy, Univ Paris-Sud, Université Paris-Saclay, Chatenay-Malabry, France
| | - Nathalie Mougenot
- Sorbonne Université, UPMC Paris 06, INSERM UMS28 Phénotypage du petit animal, Faculté de Médecine Pierre et Marie Curie, Paris, France
| | - Karim Wahbi
- Cardiology Department, Cochin Hospital, Filière Neuromusculaire, Paris-Descartes University, Sorbonne Paris Cité University, Assistance Publique-Hôpitaux de Paris, Paris, France
| | - Gisèle Bonne
- Sorbonne Université, UPMC Paris 06, INSERM UMRS974, Center of Research in Myology, Institut de Myologie, Paris, France
| | - Antoine Muchir
- Sorbonne Université, UPMC Paris 06, INSERM UMRS974, Center of Research in Myology, Institut de Myologie, Paris, France
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10
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Abdelfatah N, Chen R, Duff HJ, Seifer CM, Buffo I, Huculak C, Clarke S, Clegg R, Jassal DS, Gordon PMK, Ober C, Frosk P, Gerull B. Characterization of a Unique Form of Arrhythmic Cardiomyopathy Caused by Recessive Mutation in LEMD2. JACC Basic Transl Sci 2019; 4:204-221. [PMID: 31061923 PMCID: PMC6488817 DOI: 10.1016/j.jacbts.2018.12.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Revised: 11/02/2018] [Accepted: 12/03/2018] [Indexed: 02/08/2023]
Abstract
Nuclear envelope proteins have been shown to play an important role in the pathogenesis of inherited dilated cardiomyopathy. Here, we present a remarkable cardiac phenotype caused by a homozygous LEMD2 mutation in patients of the Hutterite population with juvenile cataract. Mutation carriers develop arrhythmic cardiomyopathy with mild impairment of left ventricular systolic function but severe ventricular arrhythmias leading to sudden cardiac death. Affected cardiac tissue from a deceased patient and fibroblasts exhibit elongated nuclei with abnormal condensed heterochromatin at the periphery. The patient fibroblasts demonstrate cellular senescence and reduced proliferation capacity, which may suggest an involvement of LEM domain containing protein 2 in chromatin remodeling processes and premature aging.
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Key Words
- ACM, arrhythmogenic cardiomyopathy
- BANF, barrier to autointegration factor
- CMR, cardiac magnetic resonance
- DAPI, 4′,6′-diamidino-2-phenylindole
- DCM, dilated cardiomyopathy
- DNA, deoxyribonucleic acid
- EMD, emerin
- ICD, implantable cardioverter-defibrillator
- LEMD2
- LEMD2, LEM domain containing protein 2
- LGE, late gadolinium enhancement
- LMNA, lamin A/C
- LV, left ventricular
- NE, nuclear envelope
- P, passage
- PBS, phosphate-buffered saline
- SAHF, senescence-associated heterochromatin foci
- SNV, single nucleotide variant
- chromatin remodeling
- dilated cardiomyopathy
- eGFP, enhanced green fluorescent protein
- inner nuclear membrane
- sudden death
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Affiliation(s)
- Nelly Abdelfatah
- Department of Cardiac Sciences, Libin Cardiovascular Institute of Alberta, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Ruping Chen
- Comprehensive Heart Failure Center, University Hospital Würzburg, Würzburg, Germany
| | - Henry J Duff
- Department of Cardiac Sciences, Libin Cardiovascular Institute of Alberta, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Colette M Seifer
- Section of Cardiology, Department of Internal Medicine, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Ilan Buffo
- Variety Children's Heart Centre, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Cathleen Huculak
- Department of Medical Genetics, Alberta Health Services, Calgary, Alberta, Canada
| | - Stephanie Clarke
- Department of Biochemistry and Medical Genetics, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Robin Clegg
- Department of Pediatrics, University of Calgary, Calgary, Alberta, Canada
| | - Davinder S Jassal
- Section of Cardiology, Department of Internal Medicine, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Paul M K Gordon
- Cumming School of Medicine Centre for Health Genomics and Informatics, University of Calgary, Calgary, Alberta, Canada
| | - Carole Ober
- Department of Human Genetics, The University of Chicago, Chicago, Illinois
| | | | - Patrick Frosk
- Department of Biochemistry and Medical Genetics, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada.,Department of Pediatrics and Child Health, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Brenda Gerull
- Department of Cardiac Sciences, Libin Cardiovascular Institute of Alberta, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Comprehensive Heart Failure Center, University Hospital Würzburg, Würzburg, Germany.,Department of Internal Medicine I, University Hospital Würzburg, Würzburg, Germany
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11
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Cellular and Animal Models of Striated Muscle Laminopathies. Cells 2019; 8:cells8040291. [PMID: 30934932 PMCID: PMC6523539 DOI: 10.3390/cells8040291] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Revised: 03/18/2019] [Accepted: 03/25/2019] [Indexed: 01/12/2023] Open
Abstract
The lamin A/C (LMNA) gene codes for nuclear intermediate filaments constitutive of the nuclear lamina. LMNA has 12 exons and alternative splicing of exon 10 results in two major isoforms—lamins A and C. Mutations found throughout the LMNA gene cause a group of diseases collectively known as laminopathies, of which the type, diversity, penetrance and severity of phenotypes can vary from one individual to the other, even between individuals carrying the same mutation. The majority of the laminopathies affect cardiac and/or skeletal muscles. The underlying molecular mechanisms contributing to such tissue-specific phenotypes caused by mutations in a ubiquitously expressed gene are not yet well elucidated. This review will explore the different phenotypes observed in established models of striated muscle laminopathies and their respective contributions to advancing our understanding of cardiac and skeletal muscle-related laminopathies. Potential future directions for developing effective treatments for patients with lamin A/C mutation-associated cardiac and/or skeletal muscle conditions will be discussed.
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12
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Brull A, Morales Rodriguez B, Bonne G, Muchir A, Bertrand AT. The Pathogenesis and Therapies of Striated Muscle Laminopathies. Front Physiol 2018; 9:1533. [PMID: 30425656 PMCID: PMC6218675 DOI: 10.3389/fphys.2018.01533] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Accepted: 10/11/2018] [Indexed: 01/04/2023] Open
Abstract
Emery-Dreifuss muscular dystrophy (EDMD) is a genetic condition characterized by early contractures, skeletal muscle weakness, and cardiomyopathy. During the last 20 years, various genetic approaches led to the identification of causal genes of EDMD and related disorders, all encoding nuclear envelope proteins. By their respective localization either at the inner nuclear membrane or the outer nuclear membrane, these proteins interact with each other and establish a connection between the nucleus and the cytoskeleton. Beside this physical link, these proteins are also involved in mechanotransduction, responding to environmental cues, such as increased tension of the cytoskeleton, by the activation or repression of specific sets of genes. This ability of cells to adapt to environmental conditions is altered in EDMD. Increased knowledge on the pathophysiology of EDMD has led to the development of drug or gene therapies that have been tested on mouse models. This review proposed an overview of the functions played by the different proteins involved in EDMD and related disorders and the current therapeutic approaches tested so far.
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Affiliation(s)
- Astrid Brull
- Sorbonne Université, INSERM, Institut de Myologie, Center of Research in Myology, UMRS 974, Paris, France
| | - Blanca Morales Rodriguez
- Sorbonne Université, INSERM, Institut de Myologie, Center of Research in Myology, UMRS 974, Paris, France.,Sanofi R&D, Chilly Mazarin, France
| | - Gisèle Bonne
- Sorbonne Université, INSERM, Institut de Myologie, Center of Research in Myology, UMRS 974, Paris, France
| | - Antoine Muchir
- Sorbonne Université, INSERM, Institut de Myologie, Center of Research in Myology, UMRS 974, Paris, France
| | - Anne T Bertrand
- Sorbonne Université, INSERM, Institut de Myologie, Center of Research in Myology, UMRS 974, Paris, France
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13
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Steele-Stallard HB, Pinton L, Sarcar S, Ozdemir T, Maffioletti SM, Zammit PS, Tedesco FS. Modeling Skeletal Muscle Laminopathies Using Human Induced Pluripotent Stem Cells Carrying Pathogenic LMNA Mutations. Front Physiol 2018; 9:1332. [PMID: 30405424 PMCID: PMC6201196 DOI: 10.3389/fphys.2018.01332] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 09/04/2018] [Indexed: 01/03/2023] Open
Abstract
Laminopathies are a clinically heterogeneous group of disorders caused by mutations in LMNA. The main proteins encoded by LMNA are Lamin A and C, which together with Lamin B1 and B2, form the nuclear lamina: a mesh-like structure located underneath the inner nuclear membrane. Laminopathies show striking tissue specificity, with subtypes affecting striated muscle, peripheral nerve, and adipose tissue, while others cause multisystem disease with accelerated aging. Although several pathogenic mechanisms have been proposed, the exact pathophysiology of laminopathies remains unclear, compounded by the rarity of these disorders and lack of easily accessible cell types to study. To overcome this limitation, we used induced pluripotent stem cells (iPSCs) from patients with skeletal muscle laminopathies such as LMNA-related congenital muscular dystrophy and limb-girdle muscular dystrophy 1B, to model disease phenotypes in vitro. iPSCs can be derived from readily accessible cell types, have unlimited proliferation potential and can be differentiated into cell types that would otherwise be difficult and invasive to obtain. iPSC lines from three skeletal muscle laminopathy patients were differentiated into inducible myogenic cells and myotubes. Disease-associated phenotypes were observed in these cells, including abnormal nuclear shape and mislocalization of nuclear lamina proteins. Nuclear abnormalities were less pronounced in monolayer cultures of terminally differentiated skeletal myotubes than in proliferating myogenic cells. Notably, skeletal myogenic differentiation of LMNA-mutant iPSCs in artificial muscle constructs improved detection of myonuclear abnormalities compared to conventional monolayer cultures across multiple pathogenic genotypes, providing a high-fidelity modeling platform for skeletal muscle laminopathies. Our results lay the foundation for future iPSC-based therapy development and screening platforms for skeletal muscle laminopathies.
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Affiliation(s)
- Heather B Steele-Stallard
- Department of Cell and Developmental Biology, University College London, London, United Kingdom.,Randall Centre for Cell and Molecular Biophysics, King's College London, London, United Kingdom
| | - Luca Pinton
- Department of Cell and Developmental Biology, University College London, London, United Kingdom.,Randall Centre for Cell and Molecular Biophysics, King's College London, London, United Kingdom
| | - Shilpita Sarcar
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | - Tanel Ozdemir
- Department of Cell and Developmental Biology, University College London, London, United Kingdom.,Randall Centre for Cell and Molecular Biophysics, King's College London, London, United Kingdom
| | - Sara M Maffioletti
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | - Peter S Zammit
- Randall Centre for Cell and Molecular Biophysics, King's College London, London, United Kingdom
| | - Francesco Saverio Tedesco
- Department of Cell and Developmental Biology, University College London, London, United Kingdom.,The Dubowitz Neuromuscular Centre, UCL Great Ormond Street Institute of Child Health, London, United Kingdom
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14
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Gerbino A, Procino G, Svelto M, Carmosino M. Role of Lamin A/C Gene Mutations in the Signaling Defects Leading to Cardiomyopathies. Front Physiol 2018; 9:1356. [PMID: 30319452 PMCID: PMC6167438 DOI: 10.3389/fphys.2018.01356] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 09/07/2018] [Indexed: 01/03/2023] Open
Abstract
Nuclear lamin A/C are crucial components of the intricate protein mesh that underlies the inner nuclear membrane and confers mainly nuclear and cytosolic rigidity. However, throughout the years a number of other key physiological processes have been associated with lamins such as modulation of both genes expression and the activity of signaling mediators. To further solidify its importance in cell physiology, mutations in the lamin A/C gene (LMNA) have been associated to diverse pathological phenotypes with skeletal muscles and the heart being the most affected systems. When affected, the heart develops a wide array of phenotypes spanning from dilated cardiomyopathy with conduction defects to arrhythmogenic right ventricular cardiomyopathy. The surprising large number of cardiac phenotypes reflects the equally large number of specific mutations identified in the LMNA gene. In this review, we underlie how mutations in LMNA can impact the activity and the spatial/temporal organization of signaling mediators and transcription factors. We analyzed the ever-increasing amount of findings collected in LmnaH222P/H222P mice whose cardiomyopathy resemble the most important features of the disease in humans and a number of key evidences from other experimental models. With this mini review, we attempt to combine the newest insights regarding both the pathogenic effects of LMNA mutations in terms of signaling abnormalities and cardiac laminopathies.
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Affiliation(s)
- Andrea Gerbino
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari Aldo Moro, Bari, Italy
| | - Giuseppe Procino
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari Aldo Moro, Bari, Italy
| | - Maria Svelto
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari Aldo Moro, Bari, Italy
| | - Monica Carmosino
- Department of Sciences, University of Basilicata, Potenza, Italy
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15
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Braumann S, Thottakara T, Stücker S, Reischmann-Düsener S, Krämer E, Groß J, Hirt MN, Doroudgar S, Carrier L, Friedrich FW. S100A4 as a Target of the E3-Ligase Asb2β and Its Effect on Engineered Heart Tissue. Front Physiol 2018; 9:1292. [PMID: 30283351 PMCID: PMC6157440 DOI: 10.3389/fphys.2018.01292] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Accepted: 08/27/2018] [Indexed: 12/12/2022] Open
Abstract
Background: S100A4 has recently emerged as an important player in cardiac disease, affecting phenotype development in animal models of myocardial infarction and pathological cardiac hypertrophy, albeit it is unclear whether S100A4 exerts a detrimental or beneficial function. The goal of the current study was to analyze S100A4 expression in models of cardiac pathology, investigate its degradation by the ubiquitin-proteasome system (UPS), and furthermore examine the functional effects of S100A4 levels in a 3D model of engineered heart tissue (EHT). Methods and Results: S100A4 mRNA and protein levels were analyzed in different models of cardiac pathology via quantitative RT-PCR and Western blot, showing a higher S100A4 steady-state protein concentration in hearts of Mybpc3-knock-in (KI) hypertrophic cardiomyopathy (HCM) mice. COS-7 cells co-transfected with plasmids encoding mutant (MUT) Asb2β lacking the E3 ligase activity in combination with V5-tagged S100A4 plasmid presented higher S100A4-V5 protein steady-state concentrations than cells co-transfected with the Asb2β wild type (WT) plasmid. This effect was blunted by treatment with the specific proteasome inhibitor epoxomicin. Adeno-associated virus serotype 6 (AAV6)-mediated S100A4 overexpression in a 3D model of EHT did not affect contractile parameters. Immunofluorescence analysis showed a cytosolic and partly nuclear expression pattern of S100A4. Gene expression analysis in EHTs overexpressing S100A4-V5 showed markedly lower steady-state concentrations of genes involved in cardiac fibrosis and pathological cardiac hypertrophy. Conclusion: We showed that S100A4 protein level is higher in cardiac tissue of Mybpc3-KI HCM mice probably as a result of a lower degradation by the E3 ligase Asb2β. While an overexpression of S100A4 did not alter contractile parameters in EHTs, downstream gene expression analysis points toward modulation of signaling cascades involved in fibrosis and hypertrophy.
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Affiliation(s)
- Simon Braumann
- Cardiovascular Research Center, Institute of Experimental Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,DZHK (German Centre for Cardiovascular Research), Partner Site Hamburg/Kiel/Lübeck, Hamburg, Germany.,Department of Cardiology, Heart Center, Cologne Cardiovascular Research Center, University of Cologne, Cologne, Germany
| | - Tilo Thottakara
- Cardiovascular Research Center, Institute of Experimental Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,DZHK (German Centre for Cardiovascular Research), Partner Site Hamburg/Kiel/Lübeck, Hamburg, Germany
| | - Sabrina Stücker
- Cardiovascular Research Center, Institute of Experimental Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,DZHK (German Centre for Cardiovascular Research), Partner Site Hamburg/Kiel/Lübeck, Hamburg, Germany
| | - Silke Reischmann-Düsener
- Cardiovascular Research Center, Institute of Experimental Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,DZHK (German Centre for Cardiovascular Research), Partner Site Hamburg/Kiel/Lübeck, Hamburg, Germany
| | - Elisabeth Krämer
- Cardiovascular Research Center, Institute of Experimental Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,DZHK (German Centre for Cardiovascular Research), Partner Site Hamburg/Kiel/Lübeck, Hamburg, Germany
| | - Julia Groß
- Department of Cardiology, Angiology, and Pneumology, Heidelberg University Hospital, Heidelberg, Germany.,DZHK (German Centre for Cardiovascular Research), Partner Site Heidelberg/Mannheim, Heidelberg, German
| | - Marc N Hirt
- Cardiovascular Research Center, Institute of Experimental Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,DZHK (German Centre for Cardiovascular Research), Partner Site Hamburg/Kiel/Lübeck, Hamburg, Germany
| | - Shirin Doroudgar
- Department of Cardiology, Angiology, and Pneumology, Heidelberg University Hospital, Heidelberg, Germany.,DZHK (German Centre for Cardiovascular Research), Partner Site Heidelberg/Mannheim, Heidelberg, German
| | - Lucie Carrier
- Cardiovascular Research Center, Institute of Experimental Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,DZHK (German Centre for Cardiovascular Research), Partner Site Hamburg/Kiel/Lübeck, Hamburg, Germany
| | - Felix W Friedrich
- Cardiovascular Research Center, Institute of Experimental Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,DZHK (German Centre for Cardiovascular Research), Partner Site Hamburg/Kiel/Lübeck, Hamburg, Germany
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16
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Razmara E, Garshasbi M. Whole-exome sequencing identifies R1279X of MYH6 gene to be associated with congenital heart disease. BMC Cardiovasc Disord 2018; 18:137. [PMID: 29969989 PMCID: PMC6029398 DOI: 10.1186/s12872-018-0867-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Accepted: 06/20/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Myosin VI, encoded by MYH6, is expressed dominantly in human cardiac atria and plays consequential roles in cardiac muscle contraction and comprising the cardiac muscle thick filament. It has been reported that the mutations in the MYH6 gene associated with sinus venosus atrial septal defect (ASD type III), hypertrophic (HCM) and dilated (DCM) cardiomyopathies. METHODS Two patients in an Iranian family have been identified who affected to Congenital Heart Disease (CHD). The male patient, besides CHD, shows that the thyroglossal sinus, refractive errors of the eye and mitral stenosis. The first symptoms emerged at the birth and diagnosis based on clinical features was made at about 5 years. The family had a history of ASD. For recognizing mutated gene (s), whole exome sequencing (WES) was performed for the male patient and variants were analyzed by autosomal dominant inheritance mode. RESULTS Eventually, by several filtering processes, a mutation in MYH6 gene (NM_002471.3), c.3835C > T; R1279X, was identified as the most likely disease-susceptibility variant and then confirmed by Sanger sequencing in the family. The mutation frequency was checked out in the local databases. This mutation results in the elimination of the 660 amino acids in the C-terminal of Myosin VI protein, including the vital parts of the coiled-coil structure of the tail domain. CONCLUSIONS Our study represents the first case of Sinus venosus defect caused directly by MYH6 stop codon mutation. Our data indicate that by increase haploinsufficiency of myosin VI, c.3835C > T mutation with reduced penetrance could be associated with CHD.
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Affiliation(s)
- Ehsan Razmara
- Department of Medical Genetics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Masoud Garshasbi
- Department of Medical Genetics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
- Department of Medical Genetics, DeNA laboratory, Tehran, Iran
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17
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Linker of nucleoskeleton and cytoskeleton complex proteins in cardiomyopathy. Biophys Rev 2018; 10:1033-1051. [PMID: 29869195 PMCID: PMC6082319 DOI: 10.1007/s12551-018-0431-6] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Accepted: 05/24/2018] [Indexed: 12/21/2022] Open
Abstract
The linker of nucleoskeleton and cytoskeleton (LINC) complex couples the nuclear lamina to the cytoskeleton. The LINC complex and its associated proteins play diverse roles in cells, ranging from genome organization, nuclear morphology, gene expression, to mechanical stability. The importance of a functional LINC complex is highlighted by the large number of mutations in genes encoding LINC complex proteins that lead to skeletal and cardiac myopathies. In this review, the structure, function, and interactions between components of the LINC complex will be described. Mutations that are known to cause cardiomyopathy in patients will be discussed alongside their respective mouse models. Furthermore, future challenges for the field and emerging technologies to investigate LINC complex function will be discussed.
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18
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Gavazzoni M, Vizzardi E, Gorga E, Bonadei I, Rossi L, Belotti A, Rossi G, Ribolla R, Metra M, Raddino R. Mechanism of cardiovascular toxicity by proteasome inhibitors: New paradigm derived from clinical and pre-clinical evidence. Eur J Pharmacol 2018; 828:80-88. [DOI: 10.1016/j.ejphar.2018.03.022] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Revised: 03/11/2018] [Accepted: 03/14/2018] [Indexed: 01/08/2023]
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19
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Boriani G, Biagini E, Ziacchi M, Malavasi VL, Vitolo M, Talarico M, Mauro E, Gorlato G, Lattanzi G. Cardiolaminopathies from bench to bedside: challenges in clinical decision-making with focus on arrhythmia-related outcomes. Nucleus 2018; 9:442-459. [PMID: 30130999 PMCID: PMC6244733 DOI: 10.1080/19491034.2018.1506680] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 06/16/2018] [Accepted: 07/25/2018] [Indexed: 02/07/2023] Open
Abstract
Lamin A/C gene mutations can be associated with cardiac diseases, usually referred to as 'cardiolaminopathies' characterized by arrhythmic disorders and/or left ventricular or biventricular dysfunction up to an overt picture of heart failure. The phenotypic cardiac manifestations of laminopathies are frequently mixed in complex clinical patterns and specifically may include bradyarrhythmias (sinus node disease or atrioventricular blocks), atrial arrhythmias (atrial fibrillation, atrial flutter, atrial standstill), ventricular tachyarrhythmias and heart failure of variable degrees of severity. Family history, physical examination, laboratory findings (specifically serum creatine phosphokinase values) and ECG findings are often important 'red flags' in diagnosing a 'cardiolaminopathy'. Sudden arrhythmic death, thromboembolic events or stroke and severe heart failure requiring heart transplantation are the most dramatic complications of the evolution of cardiolaminopathies and appropriate risk stratification is clinically needed combined with clinical follow-up. Treatment with cardiac electrical implantable devices is indicated in case of bradyarrhythmias (implant of a device with pacemaker functions), risk of life-threatening ventricular tachyarrhythmias (implant of an ICD) or in case of heart failure with wide QRS interval (implant of a device for cardiac resynchronization). New technologies introduced in the last 5 years can help physicians to reduce device-related complications, thanks to the extension of device longevity and availability of leadless pacemakers or defibrillators, to be implanted in appropriately selected patients. An improved knowledge of the complex pathophysiological pathways involved in cardiolaminopathies and in the determinants of their progression to more severe forms will help to improve clinical management and to better target pharmacological and non-pharmacological treatments.
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Affiliation(s)
- Giuseppe Boriani
- Cardiology Division, Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Policlinico di Modena, Modena, Italy
| | - Elena Biagini
- Institute of Cardiology, Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, S.Orsola-Malpighi University Hospital, Bologna, Italy
| | - Matteo Ziacchi
- Institute of Cardiology, Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, S.Orsola-Malpighi University Hospital, Bologna, Italy
| | - Vincenzo Livio Malavasi
- Cardiology Division, Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Policlinico di Modena, Modena, Italy
| | - Marco Vitolo
- Cardiology Division, Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Policlinico di Modena, Modena, Italy
| | - Marisa Talarico
- Cardiology Division, Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Policlinico di Modena, Modena, Italy
| | - Erminio Mauro
- Cardiology Division, Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Policlinico di Modena, Modena, Italy
| | - Giulia Gorlato
- Cardiology Division, Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Policlinico di Modena, Modena, Italy
| | - Giovanna Lattanzi
- CNR Institute of Molecular Genetics, Unit of Bologna, Bologna, Italy
- Laboratory of Musculoskeletal Cell Biology, Rizzoli Orthopedic Institute, Bologna, Italy
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20
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Azibani F, Brull A, Arandel L, Beuvin M, Nelson I, Jollet A, Ziat E, Prudhon B, Benkhelifa-Ziyyat S, Bitoun M, Lorain S, Bonne G, Bertrand AT. Gene Therapy via Trans-Splicing for LMNA-Related Congenital Muscular Dystrophy. MOLECULAR THERAPY. NUCLEIC ACIDS 2017; 10:376-386. [PMID: 29499949 PMCID: PMC5862133 DOI: 10.1016/j.omtn.2017.12.012] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/06/2017] [Revised: 12/20/2017] [Accepted: 12/20/2017] [Indexed: 11/28/2022]
Abstract
We assessed the potential of Lmna-mRNA repair by spliceosome-mediated RNA trans-splicing as a therapeutic approach for LMNA-related congenital muscular dystrophy. This gene therapy strategy leads to reduction of mutated transcript expression for the benefit of corresponding wild-type (WT) transcripts. We developed 5′-RNA pre-trans-splicing molecules containing the first five exons of Lmna and targeting intron 5 of Lmna pre-mRNA. Among nine pre-trans-splicing molecules, differing in the targeted sequence in intron 5 and tested in C2C12 myoblasts, three induced trans-splicing events on endogenous Lmna mRNA and confirmed at protein level. Further analyses performed in primary myotubes derived from an LMNA-related congenital muscular dystrophy (L-CMD) mouse model led to a partial rescue of the mutant phenotype. Finally, we tested this approach in vivo using adeno-associated virus (AAV) delivery in newborn mice and showed that trans-splicing events occurred in WT mice 50 days after AAV delivery, although at a low rate. Altogether, while these results provide the first evidence for reprogramming LMNA mRNA in vitro, strategies to improve the rate of trans-splicing events still need to be developed for efficient application of this therapeutic approach in vivo.
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Affiliation(s)
- Feriel Azibani
- Sorbonne Université, INSERM UMRS_974, Center of Research in Myology, 75013 Paris, France
| | - Astrid Brull
- Sorbonne Université, INSERM UMRS_974, Center of Research in Myology, 75013 Paris, France
| | - Ludovic Arandel
- Sorbonne Université, INSERM UMRS_974, Center of Research in Myology, 75013 Paris, France
| | - Maud Beuvin
- Sorbonne Université, INSERM UMRS_974, Center of Research in Myology, 75013 Paris, France
| | - Isabelle Nelson
- Sorbonne Université, INSERM UMRS_974, Center of Research in Myology, 75013 Paris, France
| | - Arnaud Jollet
- Sorbonne Université, INSERM UMRS_974, Center of Research in Myology, 75013 Paris, France
| | - Esma Ziat
- Sorbonne Université, INSERM UMRS_974, Center of Research in Myology, 75013 Paris, France
| | - Bernard Prudhon
- Sorbonne Université, INSERM UMRS_974, Center of Research in Myology, 75013 Paris, France
| | | | - Marc Bitoun
- Sorbonne Université, INSERM UMRS_974, Center of Research in Myology, 75013 Paris, France
| | - Stéphanie Lorain
- Sorbonne Université, INSERM UMRS_974, Center of Research in Myology, 75013 Paris, France
| | - Gisèle Bonne
- Sorbonne Université, INSERM UMRS_974, Center of Research in Myology, 75013 Paris, France
| | - Anne T Bertrand
- Sorbonne Université, INSERM UMRS_974, Center of Research in Myology, 75013 Paris, France.
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21
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Martinon F. Inflammation initiated by stressed organelles. Joint Bone Spine 2017; 85:423-428. [PMID: 28705494 DOI: 10.1016/j.jbspin.2017.06.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Accepted: 06/29/2017] [Indexed: 12/21/2022]
Abstract
Key cellular functions including those related to energy metabolism, organization of the genetic information or production of membrane-bound and secreted proteins are compartmentalized within organelles. Various stresses such as differentiation programs, viral and bacterial infections, perturbations in protein production, mechanical constraints, changes in the environment and nutriment accessibility can impact cellular homeostasis and organelle integrity. Perturbations of these cellular compartments trigger repair and adaptation programs aimed at restoring homeostasis. These events are often associated with low-grade inflammation also termed parainflammation. While the nature and mechanisms of danger signals released by irremediably damaged cells are well understood, how transiently stressed cells trigger inflammation is still poorly understood. Emerging studies highlighted new mechanisms by which stress pathways promote inflammation. Cytosolic innate immune pathways are engaged by signals stemming from perturbed organelles such as the mitochondria, the endoplasmic reticulum (ER) or the nuclear envelope (NE). These observations indicate that these pathways function as guardians of cellular homeostasis and may contribute to disease in pathologies characterized by perturbations of cellular homoeostasis. Mitochondria-stress, ER-stress or NE-stress are emerging as proinflammatory signals that contribute to human conditions and diseases.
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Affiliation(s)
- Fabio Martinon
- Department of Biochemistry, University of Lausanne, Chemin Des Boveresses 155, 1066 Epalinges, Switzerland.
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22
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Abstract
The nuclear lamina is a critical structural domain for the maintenance of genomic stability and whole-cell mechanics. Mutations in the LMNA gene, which encodes nuclear A-type lamins lead to the disruption of these key cellular functions, resulting in a number of devastating diseases known as laminopathies. Cardiomyopathy is a common laminopathy and is highly penetrant with poor prognosis. To date, cell mechanical instability and dysregulation of gene expression have been proposed as the main mechanisms driving cardiac dysfunction, and indeed discoveries in these areas have provided some promising leads in terms of therapeutics. However, important questions remain unanswered regarding the role of lamin A dysfunction in the heart, including a potential role for the toxicity of lamin A precursors in LMNA cardiomyopathy, which has yet to be rigorously investigated.
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Affiliation(s)
- Daniel Brayson
- a King's College London, The James Black Centre , London , United Kingdom
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23
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Wu W, Chordia MD, Hart BP, Kumarasinghe ES, Ji MK, Bhargava A, Lawlor MW, Shin JY, Sera F, Homma S, Muchir A, Khire UR, Worman HJ. Macrocyclic MEK1/2 inhibitor with efficacy in a mouse model of cardiomyopathy caused by lamin A/C gene mutation. Bioorg Med Chem 2017; 25:1004-1013. [PMID: 28011205 PMCID: PMC5291759 DOI: 10.1016/j.bmc.2016.12.014] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Revised: 12/06/2016] [Accepted: 12/08/2016] [Indexed: 12/19/2022]
Abstract
Signaling mediated by extracellular signal-regulated kinases 1 and 2 (ERK1/2) is involved in numerous cellular processes. Mitogen-activated protein kinase kinases (MEK1/2) catalyze the phosphorylation of ERK1/2, converting it into an active kinase that regulates the expression of numerous genes and cellular processes. Inhibitors of MEK1/2 have demonstrated preclinical and clinical efficacy in certain cancers and types of cardiomyopathy. We report the synthesis of a novel, allosteric, macrocyclic MEK1/2 inhibitor that potently inhibits ERK1/2 activity in cultured cells and tissues of mice after systemic administration. Mice with dilated cardiomyopathy caused by a lamin A/C gene mutation have abnormally increased cardiac ERK1/2 activity. In these mice, this novel MEK1/2 inhibitor is well tolerated, improves left ventricular systolic function, decreases left ventricular fibrosis, has beneficial effects on skeletal muscle structure and pathology and prolongs survival. The novel MEK1/2 inhibitor described herein may therefore find clinical utility in the treatment of this rare cardiomyopathy, other types of cardiomyopathy and cancers in humans.
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Affiliation(s)
- Wei Wu
- Department of Medicine, College of Physicians & Surgeons, Columbia University, 630 West 168th Street, New York, NY 10032, United States; Department of Pathology and Cell Biology, College of Physicians & Surgeons, Columbia University, 630 West 168th Street, New York, NY 10032, United States
| | - Mahendra D Chordia
- Cheminpharma LLC, 23 Business Park Drive, Branford, CT 06405, United States
| | - Barry P Hart
- AlloMek Therapeutics LLC, 400 Farmington Avenue, Farmington, CT 06032, United States
| | | | - Min K Ji
- Cheminpharma LLC, 23 Business Park Drive, Branford, CT 06405, United States
| | - Ajay Bhargava
- Shakti BioResearch LLC, 1 Bradley Road, Suite 401, Woodbridge, CT 06525, United States
| | - Michael W Lawlor
- Department of Pathology and Laboratory Medicine, Medical College of Wisconsin, 9200 West Wisconsin Avenue, Milwaukee, WI 53226, United States
| | - Ji-Yeon Shin
- Department of Medicine, College of Physicians & Surgeons, Columbia University, 630 West 168th Street, New York, NY 10032, United States; Department of Pathology and Cell Biology, College of Physicians & Surgeons, Columbia University, 630 West 168th Street, New York, NY 10032, United States
| | - Fusako Sera
- Department of Medicine, College of Physicians & Surgeons, Columbia University, 630 West 168th Street, New York, NY 10032, United States
| | - Shunichi Homma
- Department of Medicine, College of Physicians & Surgeons, Columbia University, 630 West 168th Street, New York, NY 10032, United States
| | - Antoine Muchir
- Department of Medicine, College of Physicians & Surgeons, Columbia University, 630 West 168th Street, New York, NY 10032, United States; Department of Pathology and Cell Biology, College of Physicians & Surgeons, Columbia University, 630 West 168th Street, New York, NY 10032, United States
| | - Uday R Khire
- Cheminpharma LLC, 23 Business Park Drive, Branford, CT 06405, United States; AlloMek Therapeutics LLC, 400 Farmington Avenue, Farmington, CT 06032, United States.
| | - Howard J Worman
- Department of Medicine, College of Physicians & Surgeons, Columbia University, 630 West 168th Street, New York, NY 10032, United States; Department of Pathology and Cell Biology, College of Physicians & Surgeons, Columbia University, 630 West 168th Street, New York, NY 10032, United States.
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24
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Implications and Assessment of the Elastic Behavior of Lamins in Laminopathies. Cells 2016; 5:cells5040037. [PMID: 27754432 PMCID: PMC5187521 DOI: 10.3390/cells5040037] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Revised: 09/28/2016] [Accepted: 10/10/2016] [Indexed: 01/17/2023] Open
Abstract
Lamins are mechanosensitive and elastic components of the nuclear lamina that respond to external mechanical cues by altering gene regulation in a feedback mechanism. Numerous mutations in A-type lamins cause a plethora of diverse diseases collectively termed as laminopathies, the majority of which are characterized by irregularly shaped, fragile, and plastic nuclei. These nuclei are challenged to normal mechanotransduction and lead to disease phenotypes. Here, we review our current understanding of the nucleocytoskeleton coupling in mechanotransduction mediated by lamins. We also present an up-to-date understanding of the methods used to determine laminar elasticity both at the bulk and single molecule level.
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25
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Cattin ME, Ferry A, Vignaud A, Mougenot N, Jacquet A, Wahbi K, Bertrand AT, Bonne G. Mutation in lamin A/C sensitizes the myocardium to exercise-induced mechanical stress but has no effect on skeletal muscles in mouse. Neuromuscul Disord 2016; 26:490-9. [DOI: 10.1016/j.nmd.2016.05.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2016] [Accepted: 05/18/2016] [Indexed: 12/11/2022]
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26
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AIM2 inflammasome is activated by pharmacological disruption of nuclear envelope integrity. Proc Natl Acad Sci U S A 2016; 113:E4671-80. [PMID: 27462105 DOI: 10.1073/pnas.1602419113] [Citation(s) in RCA: 92] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Inflammasomes are critical sensors that convey cellular stress and pathogen presence to the immune system by activating inflammatory caspases and cytokines such as IL-1β. The nature of endogenous stress signals that activate inflammasomes remains unclear. Here we show that an inhibitor of the HIV aspartyl protease, Nelfinavir, triggers inflammasome formation and elicits an IL-1R-dependent inflammation in mice. We found that Nelfinavir impaired the maturation of lamin A, a structural component of the nuclear envelope, thereby promoting the release of DNA in the cytosol. Moreover, deficiency of the cytosolic DNA-sensor AIM2 impaired Nelfinavir-mediated inflammasome activation. These findings identify a pharmacologic activator of inflammasome and demonstrate the role of AIM2 in detecting endogenous DNA release upon perturbation of nuclear envelope integrity.
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Macquart C, Ben Yaou R, Muchir A, Wahbi K, Bonne G. Clinical features and therapeutic strategies for managing the striated muscle laminopathies. Expert Opin Orphan Drugs 2016. [DOI: 10.1080/21678707.2016.1180975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Coline Macquart
- Center of Research in Myology, Sorbonne Universités, UPMC Univ Paris 06, Paris, France
- INSERM, UMRS 974, Paris, France
- CNRS, FRE 3617, Paris, France
- Institut de Myologie, Paris, France
| | - Rabah Ben Yaou
- Center of Research in Myology, Sorbonne Universités, UPMC Univ Paris 06, Paris, France
- INSERM, UMRS 974, Paris, France
- CNRS, FRE 3617, Paris, France
- Institut de Myologie, Paris, France
- Centre de Référence de Maladies Neuromusculaires Paris-Est, AP-HP, Groupe Hospitalier-Universitaire La Pitié-Salpêtrière, Paris, France
| | - Antoine Muchir
- Center of Research in Myology, Sorbonne Universités, UPMC Univ Paris 06, Paris, France
- INSERM, UMRS 974, Paris, France
- CNRS, FRE 3617, Paris, France
- Institut de Myologie, Paris, France
| | - Karim Wahbi
- Center of Research in Myology, Sorbonne Universités, UPMC Univ Paris 06, Paris, France
- INSERM, UMRS 974, Paris, France
- CNRS, FRE 3617, Paris, France
- Institut de Myologie, Paris, France
- Service de cardiologie, AP-HP, Groupe Hospitalier Cochin-Broca-Hôtel Dieu, Paris, France
| | - Gisèle Bonne
- Center of Research in Myology, Sorbonne Universités, UPMC Univ Paris 06, Paris, France
- INSERM, UMRS 974, Paris, France
- CNRS, FRE 3617, Paris, France
- Institut de Myologie, Paris, France
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Abstract
The nuclear lamina (NL) is a structural component of the nuclear envelope and makes extensive contacts with integral nuclear membrane proteins and chromatin. These interactions are critical for many cellular processes, such as nuclear positioning, perception of mechanical stimuli from the cell surface, nuclear stability, 3-dimensional organization of chromatin and regulation of chromatin-binding proteins, including transcription factors. The NL is present in all nucleated metazoan cells but its composition and interactome differ between tissues. Most likely, this contributes to the broad spectrum of disease manifestations in humans with mutations in NL-related genes, ranging from muscle dystrophies to neurological disorders, lipodystrophies and progeria syndromes. We review here exciting novel insight into NL function at the cellular level, in particular in chromatin organization and mechanosensation. We also present recent observations on the relation between the NL and metabolism and the special relevance of the NL in muscle tissues. Finally, we discuss new therapeutic approaches to treat NL-related diseases.
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Affiliation(s)
- Agnieszka Dobrzynska
- a Andalusian Center for Developmental Biology (CABD) , CSIC/Junta de Andalucia/Universidad Pablo de Olavide , Seville , Spain
| | - Susana Gonzalo
- b Edward A. Doisy Department of Biochemistry and Molecular Biology , St Louis University School of Medicine , St. Louis , MO , USA
| | - Catherine Shanahan
- c BHF Center for Research Excellence , King's College London, Cardiovascular Division, James Black Center , London , UK
| | - Peter Askjaer
- a Andalusian Center for Developmental Biology (CABD) , CSIC/Junta de Andalucia/Universidad Pablo de Olavide , Seville , Spain
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Zhang H, Wang X. Priming the proteasome by protein kinase G: a novel cardioprotective mechanism of sildenafil. Future Cardiol 2015; 11:177-89. [PMID: 25760877 DOI: 10.2217/fca.15.3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The proteasome mediates the degradation of most cellular proteins including misfolded proteins, pivotal to intracellular protein hemostasis. Proteasome functional insufficiency is implicated in a large subset of human failing hearts. Experimental studies have established proteasome functional insufficiency as a major pathogenic factor, rationalizing proteasome enhancement as a potentially new therapeutic strategy for congestive heart failure. Protein kinase G activation known to be cardioprotective was recently found to facilitate proteasomal degradation of misfolded proteins in cardiomyocytes; sildenafil was shown to activate myocardial protein kinase G, improve cardiac protein quality control and slow down the progression of cardiac proteinopathy in mice. This identifies the first clinically used drug that is capable of benign proteasome enhancement and unveils a potentially novel cardioprotective mechanism for sildenafil.
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Affiliation(s)
- Hanming Zhang
- Division of Basic Biomedical Sciences, Sanford School of Medicine of the University of South Dakota, Vermillion, SD 57069, USA
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Azibani F, Bertrand AT. Gene Therapy for LMNA-related Congenital Muscular Dystrophy (L-CMD) by Trans-Splicing. Orphanet J Rare Dis 2015. [PMCID: PMC4652526 DOI: 10.1186/1750-1172-10-s2-o11] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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Muchir A, Worman HJ. Targeting Mitogen-Activated Protein Kinase Signaling in Mouse Models of Cardiomyopathy Caused by Lamin A/C Gene Mutations. Methods Enzymol 2015; 568:557-80. [PMID: 26795484 DOI: 10.1016/bs.mie.2015.07.028] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The most frequently occurring mutations in the gene encoding nuclear lamin A and nuclear lamin C cause striated muscle diseases virtually always involving the heart. In this review, we describe the approaches and methods used to discover that cardiomyopathy-causing lamin A/C gene mutations increase MAP kinase signaling in the heart and that this plays a role in disease pathogenesis. We review different mouse models of cardiomyopathy caused by lamin A/C gene mutations and how transcriptomic analysis of one model identified increased cardiac activity of the ERK1/2, JNK, and p38α MAP kinases. We describe methods used to measure the activity of these MAP kinases in mouse hearts and then discuss preclinical treatment protocols using pharmacological inhibitors to demonstrate their role in pathogenesis. Several of these kinase inhibitors are in clinical development and could potentially be used to treat human subjects with cardiomyopathy caused by lamin A/C gene mutations.
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Affiliation(s)
- Antoine Muchir
- Center of Research in Myology, UPMC-Inserm UMR974, CNRS FRE3617, Institut de Myologie, G.H. Pitie Salpetriere, Paris Cedex, France
| | - Howard J Worman
- Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, USA; Department of Pathology and Cell Biology, College of Physicians and Surgeons, Columbia University, New York, USA.
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The Cardiomyopathy Lamin A/C D192G Mutation Disrupts Whole-Cell Biomechanics in Cardiomyocytes as Measured by Atomic Force Microscopy Loading-Unloading Curve Analysis. Sci Rep 2015; 5:13388. [PMID: 26323789 PMCID: PMC4555041 DOI: 10.1038/srep13388] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Accepted: 07/23/2015] [Indexed: 12/30/2022] Open
Abstract
Atomic force microscopy (AFM) cell loading/unloading curves were used to provide comprehensive insights into biomechanical behavior of cardiomyocytes carrying the lamin A/C (LMNA) D192G mutation known to cause defective nuclear wall, myopathy and severe cardiomyopathy. Our results suggested that the LMNA D192G mutation increased maximum nuclear deformation load, nuclear stiffness and fragility as compared to controls. Furthermore, there seems to be a connection between this lamin nuclear mutation and cell adhesion behavior since LMNA D192G cardiomyocytes displayed loss of AFM probe-to-cell membrane adhesion. We believe that this loss of adhesion involves the cytoskeletal architecture since our microscopic analyses highlighted that mutant LMNA may also lead to a morphological alteration in the cytoskeleton. Furthermore, chemical disruption of the actin cytoskeleton by cytochalasin D in control cardiomyocytes mirrored the alterations in the mechanical properties seen in mutant cells, suggesting a defect in the connection between the nucleoskeleton, cytoskeleton and cell adhesion molecules in cells expressing the mutant protein. These data add to our understanding of potential mechanisms responsible for this fatal cardiomyopathy, and show that the biomechanical effects of mutant lamin extend beyond nuclear mechanics to include interference of whole-cell biomechanical properties.
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Gruenbaum Y, Foisner R. Lamins: nuclear intermediate filament proteins with fundamental functions in nuclear mechanics and genome regulation. Annu Rev Biochem 2015; 84:131-64. [PMID: 25747401 DOI: 10.1146/annurev-biochem-060614-034115] [Citation(s) in RCA: 368] [Impact Index Per Article: 40.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Lamins are intermediate filament proteins that form a scaffold, termed nuclear lamina, at the nuclear periphery. A small fraction of lamins also localize throughout the nucleoplasm. Lamins bind to a growing number of nuclear protein complexes and are implicated in both nuclear and cytoskeletal organization, mechanical stability, chromatin organization, gene regulation, genome stability, differentiation, and tissue-specific functions. The lamin-based complexes and their specific functions also provide insights into possible disease mechanisms for human laminopathies, ranging from muscular dystrophy to accelerated aging, as observed in Hutchinson-Gilford progeria and atypical Werner syndromes.
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Affiliation(s)
- Yosef Gruenbaum
- Department of Genetics, Alexander Silberman Institute of Life Sciences, Hebrew University of Jerusalem, Jerusalem 91904, Israel;
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Dorboz I, Coutelier M, Bertrand AT, Caberg JH, Elmaleh-Bergès M, Lainé J, Stevanin G, Bonne G, Boespflug-Tanguy O, Servais L. Severe dystonia, cerebellar atrophy, and cardiomyopathy likely caused by a missense mutation in TOR1AIP1. Orphanet J Rare Dis 2014; 9:174. [PMID: 25425325 PMCID: PMC4302636 DOI: 10.1186/s13023-014-0174-9] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Accepted: 10/28/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Dystonia, cerebellar atrophy, and cardiomyopathy constitute a rare association. METHODS We used homozygosity mapping and whole exome sequencing to determine the mutation, western blot and immunolabelling on cultured fibroblasts to demonstrate the lower expression and the mislocalization of the protein. RESULTS We report on a boy born from consanguineous healthy parents, who presented at three years of age with rapidly progressing dystonia, progressive cerebellar atrophy, and dilated cardiomyopathy. We identified regions of homozygosity and performed whole exome sequencing that revealed a homozygous missense mutation in TOR1AIP1. The mutation, absent in controls, results in a change of a highly conserved glutamic acid to alanine. TOR1AIP1 encodes lamina-associated polypeptide 1 (LAP1), a transmembrane protein ubiquitously expressed in the inner nuclear membrane. LAP1 interacts with torsinA, the protein mutated in DYT1-dystonia. In vitro studies in fibroblasts of the patient revealed reduced expression of LAP1 and its mislocalization and aggregation in the endoplasmic reticulum as underlying pathogenic mechanisms. CONCLUSIONS AND RELEVANCE The pathogenic role of TOR1AIP1 mutation is supported by a) the involvement of a highly conserved amino acid, b) the absence of the mutation in controls, c) the functional interaction of LAP1 with torsinA, and d) mislocalization of LAP1 in patient cells. Of note, cardiomyopathy has been reported in LAP1-null mice and in patients with the TOR1AIP1 nonsense mutation. Other cases will help delineate the clinical spectrum of LAP1-related mutations.
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Affiliation(s)
- Imen Dorboz
- Inserm U1141, Université Paris Diderot-Sorbonne Paris Cité, DHU PROTECT, Paris, F-75019, France.
| | - Marie Coutelier
- Inserm, U1127, Paris, F-75013, France. .,CNRS, UMR 7225, Paris, 75013, France. .,Université Pierre et Marie Curie - Paris 6, UMR_S 1127, Institut du Cerveau et de la Moelle épinière, CHU Pitié-Salpêtrière, 75013, Paris, France. .,Laboratoire de Neurogénétique, Ecole Pratique des Hautes Etudes, Institut du Cerveau et de la Moelle épinière, CHU Pitié-Salpêtrière, 75013, Paris, France. .,Laboratoire de Génétique Humaine, Institut de Duve, UCL, 1200, Bruxelles, Belgium.
| | - Anne T Bertrand
- Inserm, U974, Paris, F-75013, France. .,Université Pierre et Marie Curie - Paris 6, UM 76; CNRS, UMR 7215; Institut de Myologie, Paris, F-75013, France.
| | | | | | - Jeanne Lainé
- Inserm, U974, Paris, F-75013, France. .,Université Pierre et Marie Curie - Paris 6, UM 76; CNRS, UMR 7215; Institut de Myologie, Paris, F-75013, France. .,Département de Physiologie, Université Pierre et Marie Curie - Paris 6, Site Pitié-Salpêtrière, Paris, F-75013, France.
| | - Giovanni Stevanin
- Inserm, U1127, Paris, F-75013, France. .,CNRS, UMR 7225, Paris, 75013, France. .,Université Pierre et Marie Curie - Paris 6, UMR_S 1127, Institut du Cerveau et de la Moelle épinière, CHU Pitié-Salpêtrière, 75013, Paris, France. .,Laboratoire de Neurogénétique, Ecole Pratique des Hautes Etudes, Institut du Cerveau et de la Moelle épinière, CHU Pitié-Salpêtrière, 75013, Paris, France.
| | - Gisèle Bonne
- Inserm, U974, Paris, F-75013, France. .,Université Pierre et Marie Curie - Paris 6, UM 76; CNRS, UMR 7215; Institut de Myologie, Paris, F-75013, France. .,AP-HP, Groupe Hospitalier Pitié-Salpêtrière, U.F. Cardiogénétique et Myogénétique, Service de Biochimie Métabolique, Paris, F-75013, France.
| | - Odile Boespflug-Tanguy
- Inserm U1141, Université Paris Diderot-Sorbonne Paris Cité, DHU PROTECT, Paris, F-75019, France. .,Service de neurologie pédiatrique et des maladies métaboliques, Hôpital Robert Debré, Assistance Publique des Hôpitaux de Paris, 75019, Paris, France.
| | - Laurent Servais
- Service de neurologie pédiatrique et des maladies métaboliques, Hôpital Robert Debré, Assistance Publique des Hôpitaux de Paris, 75019, Paris, France. .,Centre de Référence des Maladies Neuromusculaires, Hôpital de La Citadelle, 4000, Liège, Belgium. .,Institut de Myologie, Bâtiment Babinski, Hôpital de La Pitié Salpêtrière, 48/83 boulevard de l'Hôpital, 75013, Paris, France.
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Nuclear envelope and striated muscle diseases. Curr Opin Cell Biol 2014; 32:1-6. [PMID: 25290386 DOI: 10.1016/j.ceb.2014.09.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2014] [Revised: 09/17/2014] [Accepted: 09/21/2014] [Indexed: 12/22/2022]
Abstract
The nuclear lamina is a mesh-like network of intermediate filaments localized mainly at the inner surface of the inner nuclear membrane and is composed of proteins called lamins. Many inherited diseases are linked with mutations in nuclear lamins and integral proteins of the inner nuclear membrane. In this article, we summarize basic aspects of the nuclear envelope architecture and provide some remarkable findings of the involvement of lamins in striated muscle disorders.
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Helms AS, Davis FM, Coleman D, Bartolone SN, Glazier AA, Pagani F, Yob JM, Sadayappan S, Pedersen E, Lyons R, Westfall MV, Jones R, Russell MW, Day SM. Sarcomere mutation-specific expression patterns in human hypertrophic cardiomyopathy. ACTA ACUST UNITED AC 2014; 7:434-43. [PMID: 25031304 DOI: 10.1161/circgenetics.113.000448] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
BACKGROUND Heterozygous mutations in sarcomere genes in hypertrophic cardiomyopathy (HCM) are proposed to exert their effect through gain of function for missense mutations or loss of function for truncating mutations. However, allelic expression from individual mutations has not been sufficiently characterized to support this exclusive distinction in human HCM. METHODS AND RESULTS Sarcomere transcript and protein levels were analyzed in septal myectomy and transplant specimens from 46 genotyped HCM patients with or without sarcomere gene mutations and 10 control hearts. For truncating mutations in MYBPC3, the average ratio of mutant:wild-type transcripts was ≈1:5, in contrast to ≈1:1 for all sarcomere missense mutations, confirming that nonsense transcripts are uniquely unstable. However, total MYBPC3 mRNA was significantly increased by 9-fold in HCM samples with MYBPC3 mutations compared with control hearts and with HCM samples without sarcomere gene mutations. Full-length MYBPC3 protein content was not different between MYBPC3 mutant HCM and control samples, and no truncated proteins were detected. By absolute quantification of abundance with multiple reaction monitoring, stoichiometric ratios of mutant sarcomere proteins relative to wild type were strikingly variable in a mutation-specific manner, with the fraction of mutant protein ranging from 30% to 84%. CONCLUSIONS These results challenge the concept that haploinsufficiency is a unifying mechanism for HCM caused by MYBPC3 truncating mutations. The range of allelic imbalance for several missense sarcomere mutations suggests that certain mutant proteins may be more or less stable or incorporate more or less efficiently into the sarcomere than wild-type proteins. These mutation-specific properties may distinctly influence disease phenotypes.
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Affiliation(s)
- Adam S Helms
- From the Departments of Internal Medicine (A.S.H., F.D., D.C., S.B., J.M.Y., S.M.D.), Molecular and Integrative Physiology (A.A.G., M.V.W.), Cardiac Surgery (F.P., M.V.W.), Sequencing Core (E.P., R.L.), and Pediatrics (M.W.R.), University of Michigan, Ann Arbor; Department of Cell and Molecular Physiology, Health Sciences Division, Loyola University Chicago, Maywood, IL (S.S.); and MS Bioworks, Ann Arbor, MI (R.J.)
| | - Frank M Davis
- From the Departments of Internal Medicine (A.S.H., F.D., D.C., S.B., J.M.Y., S.M.D.), Molecular and Integrative Physiology (A.A.G., M.V.W.), Cardiac Surgery (F.P., M.V.W.), Sequencing Core (E.P., R.L.), and Pediatrics (M.W.R.), University of Michigan, Ann Arbor; Department of Cell and Molecular Physiology, Health Sciences Division, Loyola University Chicago, Maywood, IL (S.S.); and MS Bioworks, Ann Arbor, MI (R.J.)
| | - David Coleman
- From the Departments of Internal Medicine (A.S.H., F.D., D.C., S.B., J.M.Y., S.M.D.), Molecular and Integrative Physiology (A.A.G., M.V.W.), Cardiac Surgery (F.P., M.V.W.), Sequencing Core (E.P., R.L.), and Pediatrics (M.W.R.), University of Michigan, Ann Arbor; Department of Cell and Molecular Physiology, Health Sciences Division, Loyola University Chicago, Maywood, IL (S.S.); and MS Bioworks, Ann Arbor, MI (R.J.)
| | - Sarah N Bartolone
- From the Departments of Internal Medicine (A.S.H., F.D., D.C., S.B., J.M.Y., S.M.D.), Molecular and Integrative Physiology (A.A.G., M.V.W.), Cardiac Surgery (F.P., M.V.W.), Sequencing Core (E.P., R.L.), and Pediatrics (M.W.R.), University of Michigan, Ann Arbor; Department of Cell and Molecular Physiology, Health Sciences Division, Loyola University Chicago, Maywood, IL (S.S.); and MS Bioworks, Ann Arbor, MI (R.J.)
| | - Amelia A Glazier
- From the Departments of Internal Medicine (A.S.H., F.D., D.C., S.B., J.M.Y., S.M.D.), Molecular and Integrative Physiology (A.A.G., M.V.W.), Cardiac Surgery (F.P., M.V.W.), Sequencing Core (E.P., R.L.), and Pediatrics (M.W.R.), University of Michigan, Ann Arbor; Department of Cell and Molecular Physiology, Health Sciences Division, Loyola University Chicago, Maywood, IL (S.S.); and MS Bioworks, Ann Arbor, MI (R.J.)
| | - Francis Pagani
- From the Departments of Internal Medicine (A.S.H., F.D., D.C., S.B., J.M.Y., S.M.D.), Molecular and Integrative Physiology (A.A.G., M.V.W.), Cardiac Surgery (F.P., M.V.W.), Sequencing Core (E.P., R.L.), and Pediatrics (M.W.R.), University of Michigan, Ann Arbor; Department of Cell and Molecular Physiology, Health Sciences Division, Loyola University Chicago, Maywood, IL (S.S.); and MS Bioworks, Ann Arbor, MI (R.J.)
| | - Jaime M Yob
- From the Departments of Internal Medicine (A.S.H., F.D., D.C., S.B., J.M.Y., S.M.D.), Molecular and Integrative Physiology (A.A.G., M.V.W.), Cardiac Surgery (F.P., M.V.W.), Sequencing Core (E.P., R.L.), and Pediatrics (M.W.R.), University of Michigan, Ann Arbor; Department of Cell and Molecular Physiology, Health Sciences Division, Loyola University Chicago, Maywood, IL (S.S.); and MS Bioworks, Ann Arbor, MI (R.J.)
| | - Sakthivel Sadayappan
- From the Departments of Internal Medicine (A.S.H., F.D., D.C., S.B., J.M.Y., S.M.D.), Molecular and Integrative Physiology (A.A.G., M.V.W.), Cardiac Surgery (F.P., M.V.W.), Sequencing Core (E.P., R.L.), and Pediatrics (M.W.R.), University of Michigan, Ann Arbor; Department of Cell and Molecular Physiology, Health Sciences Division, Loyola University Chicago, Maywood, IL (S.S.); and MS Bioworks, Ann Arbor, MI (R.J.)
| | - Ellen Pedersen
- From the Departments of Internal Medicine (A.S.H., F.D., D.C., S.B., J.M.Y., S.M.D.), Molecular and Integrative Physiology (A.A.G., M.V.W.), Cardiac Surgery (F.P., M.V.W.), Sequencing Core (E.P., R.L.), and Pediatrics (M.W.R.), University of Michigan, Ann Arbor; Department of Cell and Molecular Physiology, Health Sciences Division, Loyola University Chicago, Maywood, IL (S.S.); and MS Bioworks, Ann Arbor, MI (R.J.)
| | - Robert Lyons
- From the Departments of Internal Medicine (A.S.H., F.D., D.C., S.B., J.M.Y., S.M.D.), Molecular and Integrative Physiology (A.A.G., M.V.W.), Cardiac Surgery (F.P., M.V.W.), Sequencing Core (E.P., R.L.), and Pediatrics (M.W.R.), University of Michigan, Ann Arbor; Department of Cell and Molecular Physiology, Health Sciences Division, Loyola University Chicago, Maywood, IL (S.S.); and MS Bioworks, Ann Arbor, MI (R.J.)
| | - Margaret V Westfall
- From the Departments of Internal Medicine (A.S.H., F.D., D.C., S.B., J.M.Y., S.M.D.), Molecular and Integrative Physiology (A.A.G., M.V.W.), Cardiac Surgery (F.P., M.V.W.), Sequencing Core (E.P., R.L.), and Pediatrics (M.W.R.), University of Michigan, Ann Arbor; Department of Cell and Molecular Physiology, Health Sciences Division, Loyola University Chicago, Maywood, IL (S.S.); and MS Bioworks, Ann Arbor, MI (R.J.)
| | - Richard Jones
- From the Departments of Internal Medicine (A.S.H., F.D., D.C., S.B., J.M.Y., S.M.D.), Molecular and Integrative Physiology (A.A.G., M.V.W.), Cardiac Surgery (F.P., M.V.W.), Sequencing Core (E.P., R.L.), and Pediatrics (M.W.R.), University of Michigan, Ann Arbor; Department of Cell and Molecular Physiology, Health Sciences Division, Loyola University Chicago, Maywood, IL (S.S.); and MS Bioworks, Ann Arbor, MI (R.J.)
| | - Mark W Russell
- From the Departments of Internal Medicine (A.S.H., F.D., D.C., S.B., J.M.Y., S.M.D.), Molecular and Integrative Physiology (A.A.G., M.V.W.), Cardiac Surgery (F.P., M.V.W.), Sequencing Core (E.P., R.L.), and Pediatrics (M.W.R.), University of Michigan, Ann Arbor; Department of Cell and Molecular Physiology, Health Sciences Division, Loyola University Chicago, Maywood, IL (S.S.); and MS Bioworks, Ann Arbor, MI (R.J.)
| | - Sharlene M Day
- From the Departments of Internal Medicine (A.S.H., F.D., D.C., S.B., J.M.Y., S.M.D.), Molecular and Integrative Physiology (A.A.G., M.V.W.), Cardiac Surgery (F.P., M.V.W.), Sequencing Core (E.P., R.L.), and Pediatrics (M.W.R.), University of Michigan, Ann Arbor; Department of Cell and Molecular Physiology, Health Sciences Division, Loyola University Chicago, Maywood, IL (S.S.); and MS Bioworks, Ann Arbor, MI (R.J.).
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Merlini L, Nishino I. 201st ENMC International Workshop: Autophagy in muscular dystrophies – Translational approach, 1–3 November 2013, Bussum, The Netherlands. Neuromuscul Disord 2014; 24:546-61. [DOI: 10.1016/j.nmd.2014.03.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Revised: 03/03/2014] [Accepted: 03/13/2014] [Indexed: 12/12/2022]
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Shin JY, Le Dour C, Sera F, Iwata S, Homma S, Joseph LC, Morrow JP, Dauer WT, Worman HJ. Depletion of lamina-associated polypeptide 1 from cardiomyocytes causes cardiac dysfunction in mice. Nucleus 2014; 5:260-459. [PMID: 24859316 DOI: 10.4161/nucl.29227] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
We previously showed that striated muscle-selective depletion of lamina-associated polypeptide 1 (LAP1), an integral inner nuclear membrane protein, leads to profound muscular dystrophy with premature death in mice. As LAP1 is also depleted in hearts of these mice, we examined their cardiac phenotype. Striated muscle-selective LAP1 knockout mice display ventricular systolic dysfunction with abnormal induction of genes encoding cardiomyopathy related proteins. To eliminate possible confounding effects due to skeletal muscle pathology, we generated a new mouse line in which LAP1 is deleted in a cardiomyocyte-selective manner. These mice had no skeletal muscle pathology and appeared overtly normal at 20 weeks of age. However, cardiac echocardiography revealed that they developed left ventricular systolic dysfunction and cardiac gene expression analysis revealed abnormal induction of cardiomyopathy-related genes. Our results demonstrate that LAP1 expression in cardiomyocytes is required for normal left ventricular function, consistent with a report of cardiomyopathy in a human subject with mutation in the gene encoding LAP1.
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Affiliation(s)
- Ji-Yeon Shin
- Department of Medicine; College of Physicians & Surgeons; Columbia University; New York, NY USA; Department of Pathology and Cell Biology; College of Physicians & Surgeons; Columbia University; New York, NY USA
| | - Caroline Le Dour
- Department of Medicine; College of Physicians & Surgeons; Columbia University; New York, NY USA; Department of Pathology and Cell Biology; College of Physicians & Surgeons; Columbia University; New York, NY USA
| | - Fusako Sera
- Department of Medicine; College of Physicians & Surgeons; Columbia University; New York, NY USA
| | - Shinichi Iwata
- Department of Medicine; College of Physicians & Surgeons; Columbia University; New York, NY USA
| | - Shunichi Homma
- Department of Medicine; College of Physicians & Surgeons; Columbia University; New York, NY USA
| | - Leroy C Joseph
- Department of Medicine; College of Physicians & Surgeons; Columbia University; New York, NY USA
| | - John P Morrow
- Department of Medicine; College of Physicians & Surgeons; Columbia University; New York, NY USA
| | - William T Dauer
- Department of Neurology; University of Michigan Medical School; Ann Arbor, MI USA; Department of Cell and Developmental Biology; University of Michigan Medical School; Ann Arbor, MI USA
| | - Howard J Worman
- Department of Medicine; College of Physicians & Surgeons; Columbia University; New York, NY USA; Department of Pathology and Cell Biology; College of Physicians & Surgeons; Columbia University; New York, NY USA
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Codan B, Del Favero G, Martinelli V, Long CS, Mestroni L, Sbaizero O. Exploring the elasticity and adhesion behavior of cardiac fibroblasts by atomic force microscopy indentation. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2014; 40:427-34. [PMID: 24857511 DOI: 10.1016/j.msec.2014.04.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Revised: 02/28/2014] [Accepted: 04/02/2014] [Indexed: 12/19/2022]
Abstract
AFM was used to collect the whole force-deformation cell curves. They provide both the elasticity and adhesion behavior of mouse primary cardiac fibroblasts. To confirm the hypothesis that a link exists between the membrane receptors and the cytoskeletal filaments causing therefore changing in both elasticity and adhesion behavior, actin-destabilizing Cytochalsin D was administrated to the fibroblasts. From immunofluorescence observation and AFM loading/unloading curves, cytoskeletal reorganization as well as a change in the elasticity and adhesion was indeed observed. Elasticity of control fibroblasts is three times higher than that for fibroblasts treated with 0.5 μM Cytochalasin. Moreover, AFM loading-unloading curves clearly show the different mechanical behavior of the two different cells analyzed: (i) for control cells the AFM cantilever rises during the dwell time while cells with Cytochalasin fail to show such an active resistance; (ii) the maximum force to deform control cells is quite higher and as far as adhesion is concern (iii) the maximum separation force, detachment area and the detachment process time are much larger for control compared to the Cytochalasin treated cells. Therefore, alterations in the cytoskeleton suggest that a link must exist between the membrane receptors and the cytoskeletal filaments beneath the cellular surface and inhibition of actin polymerization has effects on the whole cell mechanical behavior as well as adhesion.
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Affiliation(s)
- B Codan
- Department of Engineering and Architecture, University of Trieste, Italy
| | - G Del Favero
- Department of Engineering and Architecture, University of Trieste, Italy
| | - V Martinelli
- Department of Engineering and Architecture, University of Trieste, Italy; International Center for Genetic Engineering and Biotechnology, Trieste, Italy
| | - C S Long
- University of Colorado Cardiovascular Institute, University of Colorado Denver, Aurora, CO, USA
| | - L Mestroni
- University of Colorado Cardiovascular Institute, University of Colorado Denver, Aurora, CO, USA
| | - O Sbaizero
- Department of Engineering and Architecture, University of Trieste, Italy.
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Cau P, Navarro C, Harhouri K, Roll P, Sigaudy S, Kaspi E, Perrin S, De Sandre-Giovannoli A, Lévy N. WITHDRAWN: Nuclear matrix, nuclear envelope and premature aging syndromes in a translational research perspective. Semin Cell Dev Biol 2014:S1084-9521(14)00058-5. [PMID: 24685615 DOI: 10.1016/j.semcdb.2014.03.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Revised: 03/03/2014] [Accepted: 03/09/2014] [Indexed: 10/25/2022]
Abstract
The Publisher regrets that this article is an accidental duplication of an article that has already been published, http://dx.doi.org/10.1016/j.semcdb.2014.03.022. The duplicate article has therefore been withdrawn. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.
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Affiliation(s)
- Pierre Cau
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France(1); INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France(1); AP-HM, Service de Biologie Cellulaire, Hôpital La Timone, 264 Rue Saint Pierre, 13385 Marseille Cedex 5, France(2).
| | - Claire Navarro
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France(1); INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France(1)
| | - Karim Harhouri
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France(1); INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France(1)
| | - Patrice Roll
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France(1); INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France(1); AP-HM, Service de Biologie Cellulaire, Hôpital La Timone, 264 Rue Saint Pierre, 13385 Marseille Cedex 5, France(2)
| | - Sabine Sigaudy
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France(1); INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France(1); AP-HM, Département de Génétique Médicale, Hôpital d'enfants Timone, 264 Rue Saint Pierre, 13385 Marseille Cedex 5, France(3)
| | - Elise Kaspi
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France(1); INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France(1); AP-HM, Service de Biologie Cellulaire, Hôpital La Timone, 264 Rue Saint Pierre, 13385 Marseille Cedex 5, France(2)
| | - Sophie Perrin
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France(1); INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France(1)
| | - Annachiara De Sandre-Giovannoli
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France(1); INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France(1); AP-HM, Département de Génétique Médicale, Hôpital d'enfants Timone, 264 Rue Saint Pierre, 13385 Marseille Cedex 5, France(3)
| | - Nicolas Lévy
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France(1); INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France(1); AP-HM, Département de Génétique Médicale, Hôpital d'enfants Timone, 264 Rue Saint Pierre, 13385 Marseille Cedex 5, France(3).
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Cau P, Navarro C, Harhouri K, Roll P, Sigaudy S, Kaspi E, Perrin S, De Sandre-Giovannoli A, Lévy N. Nuclear matrix, nuclear envelope and premature aging syndromes in a translational research perspective. Semin Cell Dev Biol 2014; 29:125-47. [PMID: 24662892 DOI: 10.1016/j.semcdb.2014.03.021] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Lamin A-related progeroid syndromes are genetically determined, extremely rare and severe. In the past ten years, our knowledge and perspectives for these diseases has widely progressed, through the progressive dissection of their pathophysiological mechanisms leading to precocious and accelerated aging, from the genes mutations discovery until therapeutic trials in affected children. A-type lamins are major actors in several structural and functional activities at the nuclear periphery, as they are major components of the nuclear lamina. However, while this is usually poorly considered, they also play a key role within the rest of the nucleoplasm, whose defects are related to cell senescence. Although nuclear shape and nuclear envelope deformities are obvious and visible events, nuclear matrix disorganization and abnormal composition certainly represent the most important causes of cell defects with dramatic pathological consequences. Therefore, lamin-associated diseases should be better referred as laminopathies instead of envelopathies, this later being too restrictive, considering neither the key structural and functional roles of soluble lamins in the entire nucleoplasm, nor the nuclear matrix contribution to the pathophysiology of lamin-associated disorders and in particular in defective lamin A processing-associated aging diseases. Based on both our understanding of pathophysiological mechanisms and the biological and clinical consequences of progeria and related diseases, therapeutic trials have been conducted in patients and were terminated less than 10 years after the gene discovery, a quite fast issue for a genetic disease. Pharmacological drugs have been repurposed and used to decrease the toxicity of the accumulated, unprocessed and truncated prelaminA in progeria. To date, none of them may be considered as a cure for progeria and these clinical strategies were essentially designed toward reducing a subset of the most dramatic and morbid features associated to progeria. New therapeutic strategies under study, in particular targeting the protein expression pathway at the mRNA level, have shown a remarkable efficacy both in vitro in cells and in vivo in mice models. Strategies intending to clear the toxic accumulated proteins from the nucleus are also under evaluation. However, although exceedingly rare, improving our knowledge of genetic progeroid syndromes and searching for innovative and efficient therapies in these syndromes is of paramount importance as, even before they can be used to save lives, they may significantly (i) expand the affected childrens' lifespan and preserve their quality of life; (ii) improve our understanding of aging-related disorders and other more common diseases; and (iii) expand our fundamental knowledge of physiological aging and its links with major physiological processes such as those involved in oncogenesis.
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Affiliation(s)
- Pierre Cau
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; AP-HM, Service de Biologie Cellulaire, Hôpital La Timone, 264 Rue Saint Pierre, 13385 Marseille Cedex 5, France.
| | - Claire Navarro
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France
| | - Karim Harhouri
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France
| | - Patrice Roll
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; AP-HM, Service de Biologie Cellulaire, Hôpital La Timone, 264 Rue Saint Pierre, 13385 Marseille Cedex 5, France
| | - Sabine Sigaudy
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; AP-HM, Département de Génétique Médicale, Hôpital d'enfants Timone, 264 Rue Saint Pierre, 13385 Marseille Cedex 5, France
| | - Elise Kaspi
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; AP-HM, Service de Biologie Cellulaire, Hôpital La Timone, 264 Rue Saint Pierre, 13385 Marseille Cedex 5, France
| | - Sophie Perrin
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France
| | - Annachiara De Sandre-Giovannoli
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; AP-HM, Département de Génétique Médicale, Hôpital d'enfants Timone, 264 Rue Saint Pierre, 13385 Marseille Cedex 5, France
| | - Nicolas Lévy
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; AP-HM, Département de Génétique Médicale, Hôpital d'enfants Timone, 264 Rue Saint Pierre, 13385 Marseille Cedex 5, France.
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Abstract
The engineering of 3-dimensional (3D) heart muscles has undergone exciting progress for the past decade. Profound advances in human stem cell biology and technology, tissue engineering and material sciences, as well as prevascularization and in vitro assay technologies make the first clinical application of engineered cardiac tissues a realistic option and predict that cardiac tissue engineering techniques will find widespread use in the preclinical research and drug development in the near future. Tasks that need to be solved for this purpose include standardization of human myocyte production protocols, establishment of simple methods for the in vitro vascularization of 3D constructs and better maturation of myocytes, and, finally, thorough definition of the predictive value of these methods for preclinical safety pharmacology. The present article gives an overview of the present state of the art, bottlenecks, and perspectives of cardiac tissue engineering for cardiac repair and in vitro testing.
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Affiliation(s)
- Marc N. Hirt
- From the Department of Experimental Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; and DZHK (German Centre for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, Hamburg, Germany
| | - Arne Hansen
- From the Department of Experimental Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; and DZHK (German Centre for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, Hamburg, Germany
| | - Thomas Eschenhagen
- From the Department of Experimental Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; and DZHK (German Centre for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, Hamburg, Germany
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43
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Abstract
Lamins A and C, encoded by LMNA, are constituent of the nuclear lamina, a meshwork of proteins underneath the nuclear envelope first described as scaffolding proteins of the nucleus. Since the discovery of LMNA mutations in highly heterogeneous human disorders (including cardiac and muscular dystrophies, lipodystrophies and progeria), the number of functions described for lamin A/C has expanded. Lamin A/C is notably involved in the regulation of chromatin structure and gene transcription, and in the resistance of cells to mechanical stress. This review focuses on studies performed on knock-out and knock-in Lmna mouse models, which have led to decipher some of the lamin A/C functions in striated muscles and to the first preclinical trials of pharmaceutical therapies.
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Neuber C, Müller OJ, Hansen FC, Eder A, Witten A, Rühle F, Stoll M, Katus HA, Eschenhagen T, El-Armouche A. Paradoxical Effects on Force Generation after Efficient β1-Adrenoceptor Knockdown in Reconstituted Heart Tissue. J Pharmacol Exp Ther 2014; 349:39-46. [DOI: 10.1124/jpet.113.210898] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
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Schlossarek S, Frey N, Carrier L. Ubiquitin-proteasome system and hereditary cardiomyopathies. J Mol Cell Cardiol 2013; 71:25-31. [PMID: 24380728 DOI: 10.1016/j.yjmcc.2013.12.016] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Revised: 11/13/2013] [Accepted: 12/17/2013] [Indexed: 12/14/2022]
Abstract
Adequate protein turnover is essential for cardiac homeostasis. Different protein quality controls are involved in the maintenance of protein homeostasis, including molecular chaperones and co-chaperones, the autophagy-lysosomal pathway, and the ubiquitin-proteasome system (UPS). In the last decade, a series of evidence has underlined a major function of the UPS in cardiac physiology and disease. Particularly, recent studies have shown that dysfunctional proteasomal function leads to cardiac disorders. Hypertrophic and dilated cardiomyopathies are the two most prevalent inherited cardiomyopathies. Both are primarily transmitted as an autosomal-dominant trait and mainly caused by mutations in genes encoding components of the cardiac sarcomere, including a relevant striated muscle-specific E3 ubiquitin ligase. A growing body of evidence indicates impairment of the UPS in inherited cardiomyopathies as determined by measurement of the level of ubiquitinated proteins, the activities of the proteasome and/or the use of fluorescent UPS reporter substrates. The present review will propose mechanisms of UPS impairment in inherited cardiomyopathies, summarize the potential consequences of UPS impairment, including activation of the unfolded protein response, and underline some therapeutic options available to restore proteasome function and therefore cardiac homeostasis and function. This article is part of a Special Issue entitled "Protein Quality Control, the Ubiquitin Proteasome System, and Autophagy".
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Affiliation(s)
- Saskia Schlossarek
- Department of Experimental Pharmacology and Toxicology, Cardiovascular Research Center, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; DZHK (German Centre for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, Germany
| | - Norbert Frey
- DZHK (German Centre for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, Germany; Department of Cardiology and Angiology, University of Kiel, Kiel, Germany
| | - Lucie Carrier
- Department of Experimental Pharmacology and Toxicology, Cardiovascular Research Center, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; DZHK (German Centre for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, Germany; Inserm, U974, Paris F-75013, France; Université Pierre et Marie Curie- Paris 6, UM 76, CNRS, UMR 7215, Institut de Myologie, IFR14, Paris F-75013, France.
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46
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Davidson PM, Lammerding J. Broken nuclei--lamins, nuclear mechanics, and disease. Trends Cell Biol 2013; 24:247-56. [PMID: 24309562 DOI: 10.1016/j.tcb.2013.11.004] [Citation(s) in RCA: 187] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2013] [Revised: 11/04/2013] [Accepted: 11/06/2013] [Indexed: 11/19/2022]
Abstract
Mutations in lamins, which are ubiquitous nuclear intermediate filaments, lead to a variety of disorders including muscular dystrophy and dilated cardiomyopathy. Lamins provide nuclear stability, help connect the nucleus to the cytoskeleton, and can modulate chromatin organization and gene expression. Nonetheless, the diverse functions of lamins remain incompletely understood. We focus here on the role of lamins on nuclear mechanics and their involvement in human diseases. Recent findings suggest that lamin mutations can decrease nuclear stability, increase nuclear fragility, and disturb mechanotransduction signaling, possibly explaining the muscle-specific defects in many laminopathies. At the same time, altered lamin expression has been reported in many cancers, where the resulting increased nuclear deformability could enhance the ability of cells to transit tight interstitial spaces, thereby promoting metastasis.
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Affiliation(s)
- Patricia M Davidson
- Weill Institute for Cell and Molecular Biology, Cornell University, 526 Campus Road, Ithaca, NY 14853, USA
| | - Jan Lammerding
- Department of Biomedical Engineering/Weill Institute for Cell and Molecular Biology, Cornell University, 526 Campus Road, Ithaca, NY 14853, USA.
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47
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Wang X, Robbins J. Proteasomal and lysosomal protein degradation and heart disease. J Mol Cell Cardiol 2013; 71:16-24. [PMID: 24239609 DOI: 10.1016/j.yjmcc.2013.11.006] [Citation(s) in RCA: 114] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Revised: 11/04/2013] [Accepted: 11/06/2013] [Indexed: 01/08/2023]
Abstract
In the cell, the proteasome and lysosomes represent the most important proteolytic machineries, responsible for the protein degradation in the ubiquitin-proteasome system (UPS) and autophagy, respectively. Both the UPS and autophagy are essential to protein quality and quantity control. Alterations in cardiac proteasomal and lysosomal degradation are remarkably associated with most heart disease in humans and are implicated in the pathogenesis of congestive heart failure. Studies carried out in animal models and in cell culture have begun to establish both sufficiency and, in some cases, the necessity of proteasomal functional insufficiency or lysosomal insufficiency as a major pathogenic factor in the heart. This review article highlights some recent advances in the research into proteasome and lysosome protein degradation in relation to cardiac pathology and examines the emerging evidence for enhancing degradative capacities of the proteasome and/or lysosome as a new therapeutic strategy for heart disease. This article is part of a Special Issue entitled "Protein Quality Control, the Ubiquitin Proteasome System, and Autophagy".
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Affiliation(s)
- Xuejun Wang
- Division of Basic Biomedical Sciences, Sanford School of Medicine of the University of South Dakota, Vermillion, SD 57069, USA.
| | - Jeffrey Robbins
- Division of Molecular Cardiovascular Biology, The Heart Institute, Department of Pediatrics, The Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
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48
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Ho CY, Jaalouk DE, Lammerding J. Novel insights into the disease etiology of laminopathies. Rare Dis 2013; 1:e27002. [PMID: 24860693 PMCID: PMC3927491 DOI: 10.4161/rdis.27002] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Revised: 10/14/2013] [Accepted: 10/30/2013] [Indexed: 12/22/2022] Open
Abstract
Laminopathies are a heterogeneous group of diseases that are caused by mutations in the nuclear envelope proteins lamins A and C. Laminopathies include dilated cardiomyopathy, Emery-Dreifuss muscular dystrophy, and familial partial lipodystrophy. Despite their near-ubiquitous expression, most laminopathies involve highly tissue-specific phenotypes, often affecting skeletal and cardiac muscle. The underlying mechanism(s) remain incompletely understood. We recently reported that altered actin dynamics in lamin A/C-deficient and mutant cells disturb nuclear shuttling of the transcriptional co-activator MKL1, which is critical for cardiac function. Expression of the inner nuclear membrane protein emerin rescues MKL1 translocation through modulating actin dynamics. Here, we elaborate on these findings, discuss new insights into the role of nuclear actin in MKL1activity, and demonstrate that primary human skin fibroblasts from a patient with dilated cardiomyopathy have impaired MKL1 nuclear translocation. These findings further strengthen the relevance of impaired MKL1 signaling as a potential contributor to the disease mechanism in laminopathies.
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Affiliation(s)
- Chin Yee Ho
- Weill Institute for Cell and Molecular Biology/Department of Biomedical Engineering; Cornell University; Ithaca, NY USA ; Department of Medicine; Brigham and Women's Hospital; Boston, MA USA
| | - Diana E Jaalouk
- Weill Institute for Cell and Molecular Biology/Department of Biomedical Engineering; Cornell University; Ithaca, NY USA ; Department of Medicine; Brigham and Women's Hospital; Boston, MA USA ; Department of Biology; American University of Beirut; Beirut, Lebanon
| | - Jan Lammerding
- Weill Institute for Cell and Molecular Biology/Department of Biomedical Engineering; Cornell University; Ithaca, NY USA ; Department of Medicine; Brigham and Women's Hospital; Boston, MA USA
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49
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Al-Saaidi R, Rasmussen TB, Palmfeldt J, Nissen PH, Beqqali A, Hansen J, Pinto YM, Boesen T, Mogensen J, Bross P. The LMNA mutation p.Arg321Ter associated with dilated cardiomyopathy leads to reduced expression and a skewed ratio of lamin A and lamin C proteins. Exp Cell Res 2013; 319:3010-9. [PMID: 24001739 DOI: 10.1016/j.yexcr.2013.08.024] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Revised: 07/31/2013] [Accepted: 08/19/2013] [Indexed: 11/19/2022]
Abstract
Dilated cardiomyopathy (DCM) is a disease of the heart muscle characterized by cardiac chamber enlargement and reduced systolic function of the left ventricle. Mutations in the LMNA gene represent the most frequent known genetic cause of DCM associated with disease of the conduction systems. The LMNA gene generates two major transcripts encoding the nuclear lamina major components lamin A and lamin C by alternative splicing. Both haploinsuffiency and dominant negative effects have been proposed as disease mechanism for premature termination codon (PTC) mutations in LMNA. These mechanisms however are still not clearly established. In this study, we used a representative LMNA nonsense mutation, p.Arg321Ter, to shed light on the molecular disease mechanisms. Cultured fibroblasts from three DCM patients carrying this mutation were analyzed. Quantitative reverse transcriptase PCR and sequencing of these PCR products indicated that transcripts from the mutant allele were degraded by the nonsense-mediated mRNA decay (NMD) mechanism. The fact that no truncated mutant protein was detectable in western blot (WB) analysis strengthens the notion that the mutant transcript is efficiently degraded. Furthermore, WB analysis showed that the expression of lamin C protein was reduced by the expected approximately 50%. Clearly decreased lamin A and lamin C levels were also observed by immunofluorescence microscopy analysis. However, results from both WB and nano-liquid chromatography/mass spectrometry demonstrated that the levels of lamin A protein were more reduced suggesting an effect on expression of lamin A from the wild type allele. PCR analysis of the ratio of lamin A to lamin C transcripts showed unchanged relative amounts of lamin A transcript suggesting that the effect on the wild type allele was operative at the protein level. Immunofluorescence microscopy analysis showed no abnormal nuclear morphology of patient fibroblast cells. Based on these data, we propose that heterozygosity for the nonsense mutation causes NMD degradation of the mutant transcripts blocking expression of the truncated mutant protein and an additional trans effect on lamin A protein levels expressed from the wild type allele. We discuss the possibility that skewing of the lamin A to lamin C ratio may contribute to ensuing processes that destabilize cardiomyocytes and trigger cardiomyopathy.
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Affiliation(s)
- Rasha Al-Saaidi
- Research Unit for Molecular Medicine, Aarhus University and Aarhus University Hospital, Aarhus, Denmark
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