101
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Savarese M, Sarparanta J, Vihola A, Udd B, Hackman P. Increasing Role of Titin Mutations in Neuromuscular Disorders. J Neuromuscul Dis 2018; 3:293-308. [PMID: 27854229 PMCID: PMC5123623 DOI: 10.3233/jnd-160158] [Citation(s) in RCA: 92] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The TTN gene with 363 coding exons encodes titin, a giant muscle protein spanning from the Z-disk to the M-band within the sarcomere. Mutations in the TTN gene have been associated with different genetic disorders, including hypertrophic and dilated cardiomyopathy and several skeletal muscle diseases. Before the introduction of next generation sequencing (NGS) methods, the molecular analysis of TTN has been laborious, expensive and not widely used, resulting in a limited number of mutations identified. Recent studies however, based on the use of NGS strategies, give evidence of an increasing number of rare and unique TTN variants. The interpretation of these rare variants of uncertain significance (VOUS) represents a challenge for clinicians and researchers. The main aim of this review is to describe the wide spectrum of muscle diseases caused by TTN mutations so far determined, summarizing the molecular findings as well as the clinical data, and to highlight the importance of joint efforts to respond to the challenges arising from the use of NGS. An international collaboration through a clinical and research consortium and the development of a single accessible database listing variants in the TTN gene, identified by high throughput approaches, may be the key to a better assessment of titinopathies and to systematic genotype– phenotype correlation studies.
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Affiliation(s)
- Marco Savarese
- Folkhälsan Institute of Genetics and Department of Medical Genetics, Haartman Institute, University of Helsinki, Helsinki, Finland
| | - Jaakko Sarparanta
- Folkhälsan Institute of Genetics and Department of Medical Genetics, Haartman Institute, University of Helsinki, Helsinki, Finland.,Albert Einstein College of Medicine, Departments of Medicine- Endocrinology and Molecular Pharmacology, Bronx, NY, USA
| | - Anna Vihola
- Folkhälsan Institute of Genetics and Department of Medical Genetics, Haartman Institute, University of Helsinki, Helsinki, Finland
| | - Bjarne Udd
- Folkhälsan Institute of Genetics and Department of Medical Genetics, Haartman Institute, University of Helsinki, Helsinki, Finland.,Neuromuscular Research Center, University of Tampere and Tampere University Hospital, Tampere, Finland.,Department of Neurology, Vaasa Central Hospital, Vaasa, Finland
| | - Peter Hackman
- Folkhälsan Institute of Genetics and Department of Medical Genetics, Haartman Institute, University of Helsinki, Helsinki, Finland
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102
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Wang L, Geist J, Grogan A, Hu LYR, Kontrogianni-Konstantopoulos A. Thick Filament Protein Network, Functions, and Disease Association. Compr Physiol 2018; 8:631-709. [PMID: 29687901 PMCID: PMC6404781 DOI: 10.1002/cphy.c170023] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Sarcomeres consist of highly ordered arrays of thick myosin and thin actin filaments along with accessory proteins. Thick filaments occupy the center of sarcomeres where they partially overlap with thin filaments. The sliding of thick filaments past thin filaments is a highly regulated process that occurs in an ATP-dependent manner driving muscle contraction. In addition to myosin that makes up the backbone of the thick filament, four other proteins which are intimately bound to the thick filament, myosin binding protein-C, titin, myomesin, and obscurin play important structural and regulatory roles. Consistent with this, mutations in the respective genes have been associated with idiopathic and congenital forms of skeletal and cardiac myopathies. In this review, we aim to summarize our current knowledge on the molecular structure, subcellular localization, interacting partners, function, modulation via posttranslational modifications, and disease involvement of these five major proteins that comprise the thick filament of striated muscle cells. © 2018 American Physiological Society. Compr Physiol 8:631-709, 2018.
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Affiliation(s)
- Li Wang
- Department of Biochemistry and Molecular Biology, University of Maryland, Baltimore, Maryland, USA
| | - Janelle Geist
- Department of Biochemistry and Molecular Biology, University of Maryland, Baltimore, Maryland, USA
| | - Alyssa Grogan
- Department of Biochemistry and Molecular Biology, University of Maryland, Baltimore, Maryland, USA
| | - Li-Yen R. Hu
- Department of Biochemistry and Molecular Biology, University of Maryland, Baltimore, Maryland, USA
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103
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Yakupova EI, Vikhlyantsev IM, Lobanov MY, Galzitskaya OV, Bobylev AG. Amyloid Properties of Titin. BIOCHEMISTRY (MOSCOW) 2018. [PMID: 29523065 DOI: 10.1134/s0006297917130077] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
This review considers data on structural and functional features of titin, on the role of this protein in determination of mechanical properties of sarcomeres, and on specific features of regulation of the stiffness and elasticity of its molecules, amyloid aggregation of this protein in vitro, and possibilities of formation of intramolecular amyloid structure in vivo. Molecular mechanisms are described of protection of titin against aggregation in muscle cells. Based on the data analysis, it is supposed that titin and the formed by it elastic filaments have features of amyloid.
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Affiliation(s)
- E I Yakupova
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino, Moscow Region, 142290, Russia.
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104
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Tasca G, Udd B. Hereditary myopathy with early respiratory failure (HMERF): Still rare, but common enough. Neuromuscul Disord 2018; 28:268-276. [DOI: 10.1016/j.nmd.2017.12.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Revised: 11/04/2017] [Accepted: 12/03/2017] [Indexed: 01/04/2023]
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105
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Guo W, Sun M. RBM20, a potential target for treatment of cardiomyopathy via titin isoform switching. Biophys Rev 2018; 10:15-25. [PMID: 28577155 PMCID: PMC5803173 DOI: 10.1007/s12551-017-0267-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Accepted: 05/16/2017] [Indexed: 12/18/2022] Open
Abstract
Cardiomyopathy, also known as heart muscle disease, is an unfavorable condition leading to alterations in myocardial contraction and/or impaired ability of ventricular filling. The onset and development of cardiomyopathy have not currently been well defined. Titin is a giant multifunctional sarcomeric filament protein that provides passive stiffness to cardiomyocytes and has been implicated to play an important role in the origin and development of cardiomyopathy and heart failure. Titin-based passive stiffness can be mainly adjusted by isoform switching and post-translational modifications in the spring regions. Recently, genetic mutations of TTN have been identified that can also contribute to variable passive stiffness, though the detailed mechanisms remain unclear. In this review, we will discuss titin isoform switching as it relates to alternative splicing during development stages and differences between species and muscle types. We provide an update on the regulatory mechanisms of TTN splicing controlled by RBM20 and cover the roles of TTN splicing in adjusting the diastolic stiffness and systolic compliance of the healthy and the failing heart. Finally, this review attempts to provide future directions for RBM20 as a potential target for pharmacological intervention in cardiomyopathy and heart failure.
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Affiliation(s)
- Wei Guo
- Animal Science, University of Wyoming, Laramie, WY, 82071, USA.
- Center for Cardiovascular Research and Integrative Medicine, University of Wyoming, Laramie, WY, 82071, USA.
| | - Mingming Sun
- Animal Science, University of Wyoming, Laramie, WY, 82071, USA
- Center for Cardiovascular Research and Integrative Medicine, University of Wyoming, Laramie, WY, 82071, USA
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106
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Bian H, Gao S, Zhang D, Zhao Q, Li F, Li X, Sun S, Song S, Li T, Zhu Q, Ren W, Qin C, Qi J. The E3 ubiquitin ligase MuRF2 attenuates LPS-induced macrophage activation by inhibiting production of inflammatory cytokines and migration. FEBS Open Bio 2018; 8:234-243. [PMID: 29435413 PMCID: PMC5794466 DOI: 10.1002/2211-5463.12367] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Revised: 11/15/2017] [Accepted: 11/24/2017] [Indexed: 01/06/2023] Open
Abstract
Muscle RING-finger (MuRF) proteins are E3 ubiquitin ligases that are expressed in striated muscle. MuRF2 is an important member of this family, but whether it is expressed in tissues other than striated muscle has not been thoroughly elucidated to date. In this study, we determined that MuRF2 is also expressed in other vital organs, including liver, lung, brain, spleen and kidney. Moreover, we show that the level of MuRF2 expression is significantly decreased in hepatic mononuclear cells of mice with lipopolysaccharide (LPS)/d-galactosamine-induced hepatitis and negatively correlated with the serum levels of alanine aminotransferase and aspartate aminotransferase in these mice. Furthermore, the expression of MuRF2 was down-regulated in RAW264.7 cells activated with LPS but not in cells treated with polyinosinic-polycytidylic acid (Poly(I:C)) or with lipidosome plus Poly(I:C). We also found that MuRF2 was able to translocate from the cytoplasm to the nucleus in RAW264.7 cells activated with LPS but not in cells treated with Poly(I:C). In addition, we demonstrated that interleukin 6 and tumour necrosis factor α production and macrophage migration were inhibited after MuRF2 was overexpressed in RAW264.7 cells. We further verified that nuclear factor-κB p65 subunit level was greatly reduced in RAW264.7 macrophage nuclei by gain of function. Taken together, these findings indicate that MuRF2 may rescue LPS-induced macrophage activation by suppressing the production of proinflammatory cytokines and cell migration. We also identify a novel function of MuRF2 in non-muscle tissues and cells.
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Affiliation(s)
- Hongjun Bian
- Shandong Provincial Hospital Affiliated to Shandong University Jinan China.,Shandong Provincial Engineering and Technological Research Center for Liver Diseases Prevention and Control Jinan China
| | - Shanshan Gao
- Shandong Provincial Hospital Affiliated to Shandong University Jinan China.,Shandong Provincial Engineering and Technological Research Center for Liver Diseases Prevention and Control Jinan China
| | - Di Zhang
- Shandong Provincial Hospital Affiliated to Shandong University Jinan China.,Shandong Provincial Engineering and Technological Research Center for Liver Diseases Prevention and Control Jinan China
| | - Qi Zhao
- Shandong Provincial Hospital Affiliated to Shandong University Jinan China.,Shandong Provincial Engineering and Technological Research Center for Liver Diseases Prevention and Control Jinan China
| | - Feifei Li
- Shandong Provincial Hospital Affiliated to Shandong University Jinan China.,Shandong Provincial Engineering and Technological Research Center for Liver Diseases Prevention and Control Jinan China
| | - Xiao Li
- Shandong Provincial Hospital Affiliated to Shandong University Jinan China.,Shandong Provincial Engineering and Technological Research Center for Liver Diseases Prevention and Control Jinan China
| | - Shuohuan Sun
- Shandong Provincial Hospital Affiliated to Shandong University Jinan China.,Shandong Provincial Engineering and Technological Research Center for Liver Diseases Prevention and Control Jinan China
| | - Shouyang Song
- Shandong Provincial Hospital Affiliated to Shandong University Jinan China.,Shandong Provincial Engineering and Technological Research Center for Liver Diseases Prevention and Control Jinan China
| | - Tao Li
- Shandong Provincial Hospital Affiliated to Shandong University Jinan China.,Shandong Provincial Engineering and Technological Research Center for Liver Diseases Prevention and Control Jinan China
| | - Qiang Zhu
- Shandong Provincial Hospital Affiliated to Shandong University Jinan China.,Shandong Provincial Engineering and Technological Research Center for Liver Diseases Prevention and Control Jinan China
| | - Wanhua Ren
- Shandong Provincial Hospital Affiliated to Shandong University Jinan China.,Shandong Provincial Engineering and Technological Research Center for Liver Diseases Prevention and Control Jinan China
| | - Chengyong Qin
- Shandong Provincial Hospital Affiliated to Shandong University Jinan China.,Shandong Provincial Engineering and Technological Research Center for Liver Diseases Prevention and Control Jinan China
| | - Jianni Qi
- Shandong Provincial Hospital Affiliated to Shandong University Jinan China.,Shandong Provincial Engineering and Technological Research Center for Liver Diseases Prevention and Control Jinan China
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107
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Friedrich O, Diermeier S, Larsson L. Weak by the machines: muscle motor protein dysfunction - a side effect of intensive care unit treatment. Acta Physiol (Oxf) 2018; 222. [PMID: 28387014 DOI: 10.1111/apha.12885] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 03/12/2017] [Accepted: 04/04/2017] [Indexed: 12/25/2022]
Abstract
Intensive care interventions involve periods of mechanical ventilation, sedation and complete mechanical silencing of patients. Critical illness myopathy (CIM) is an ICU-acquired myopathy that is associated with limb muscle weakness, muscle atrophy, electrical silencing of muscle and motor proteinopathy. The hallmark of CIM is a preferential muscle myosin loss due to increased catabolic and reduced anabolic activity. The ubiquitin proteasome pathway plays an important role, apart from recently identified novel mechanisms affecting non-lysosomal protein degradation or autophagy. CIM is not reproduced by pure disuse atrophy, denervation atrophy, steroid-induced atrophy or septic myopathy, although combinations of high-dose steroids and denervation can mimic CIM. New animal models of critical illness and ICU treatment (i.e. mechanical ventilation and complete immobilization) provide novel insights regarding the time course of protein synthesis and degradation alterations, and the role of protective chaperone activities in the process of myosin loss. Altered mechano-signalling seems involved in triggering a major part of myosin loss in experimental CIM models, and passive loading of muscle potently ameliorates the CIM phenotype. We provide a systematic overview of similarities and distinct differences in the signalling pathways involved in triggering muscle atrophy in CIM and isolated trigger factors. As preferential myosin loss is mostly determined from biochemistry analyses providing no spatial resolution of myosin loss processes within myofibres, we also provide first results monitoring myosin signal intensities during experimental ICU intervention using multi-photon Second Harmonic Generation microscopy. Our results confirm that myosin loss is an evenly distributed process within myofibres rather than being confined to hot spots.
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Affiliation(s)
- O. Friedrich
- Institute of Medical Biotechnology; Friedrich-Alexander-University Erlangen-Nürnberg; Erlangen Germany
- Erlangen Graduate School in Advanced Optical Technologie (SAOT); Friedrich-Alexander-University Erlangen-Nürnberg; Erlangen Germany
| | - S. Diermeier
- Institute of Medical Biotechnology; Friedrich-Alexander-University Erlangen-Nürnberg; Erlangen Germany
- Erlangen Graduate School in Advanced Optical Technologie (SAOT); Friedrich-Alexander-University Erlangen-Nürnberg; Erlangen Germany
| | - L. Larsson
- Department of Physiology & Pharmacology; Karolinska Institutet; Stockholm Sweden
- Section of Clinical Neurophysiology; Department of Clinical Neuroscience; Karolinska Institutet; Stockholm Sweden
- Department of Biobehavioral Health; The Pennsylvania State University; University Park PA USA
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108
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Carlisle C, Prill K, Pilgrim D. Chaperones and the Proteasome System: Regulating the Construction and Demolition of Striated Muscle. Int J Mol Sci 2017; 19:E32. [PMID: 29271938 PMCID: PMC5795982 DOI: 10.3390/ijms19010032] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2017] [Revised: 11/28/2017] [Accepted: 12/18/2017] [Indexed: 12/21/2022] Open
Abstract
Protein folding factors (chaperones) are required for many diverse cellular functions. In striated muscle, chaperones are required for contractile protein function, as well as the larger scale assembly of the basic unit of muscle, the sarcomere. The sarcomere is complex and composed of hundreds of proteins and the number of proteins and processes recognized to be regulated by chaperones has increased dramatically over the past decade. Research in the past ten years has begun to discover and characterize the chaperones involved in the assembly of the sarcomere at a rapid rate. Because of the dynamic nature of muscle, wear and tear damage is inevitable. Several systems, including chaperones and the ubiquitin proteasome system (UPS), have evolved to regulate protein turnover. Much of our knowledge of muscle development focuses on the formation of the sarcomere but recent work has begun to elucidate the requirement and role of chaperones and the UPS in sarcomere maintenance and disease. This review will cover the roles of chaperones in sarcomere assembly, the importance of chaperone homeostasis and the cooperation of chaperones and the UPS in sarcomere integrity and disease.
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Affiliation(s)
- Casey Carlisle
- Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada.
| | - Kendal Prill
- Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada.
| | - Dave Pilgrim
- Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada.
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109
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Hartupee J, Szalai GD, Wang W, Ma X, Diwan A, Mann DL. Impaired Protein Quality Control During Left Ventricular Remodeling in Mice With Cardiac Restricted Overexpression of Tumor Necrosis Factor. Circ Heart Fail 2017; 10:CIRCHEARTFAILURE.117.004252. [PMID: 29203562 DOI: 10.1161/circheartfailure.117.004252] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Accepted: 11/09/2017] [Indexed: 11/16/2022]
Abstract
BACKGROUND Sustained inflammation in the heart is sufficient to provoke left ventricular dysfunction and left ventricular remodeling. Although inflammation has been linked to many of the biological changes responsible for adverse left ventricular remodeling, the relationship between inflammation and protein quality control in the heart is not well understood. METHODS AND RESULTS To study the relationship between chronic inflammation and protein quality control, we used a mouse model of dilated cardiomyopathy driven by cardiac restricted overexpression of TNF (tumor necrosis factor; Myh6-sTNF). Myh6-sTNF mice develop protein aggregates containing ubiquitin-tagged proteins within cardiac myocytes related to proteasome dysfunction and impaired autophagy. The 26S proteasome was dysfunctional despite normal function of the core 20S subunit. We found an accumulation of autophagy substrates in Myh6-sTNF mice, which were also seen in tissue from patients with end-stage heart failure. Moreover, there was evidence of impaired autophagosome clearance after chloroquine administration in these mice indicative of impaired autophagic flux. Finally, there was increased mammalian target of rapamycin complex 1 (mTORC1) activation, which has been linked to inhibition of both the proteasome and autophagy. CONCLUSIONS Myh6-sTNF mice with sustained inflammatory signaling develop proteasome dysfunction and impaired autophagic flux that is associated with enhanced mTORC1 activation.
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Affiliation(s)
- Justin Hartupee
- From the Cardiovascular Division, Department of Medicine, Washington University School of Medicine, St. Louis, MO (J.H., X.M., A.D., D.L.M.); John Cochran VA Medical Center, St. Louis, MO (A.D.); and Winters Center for Heart Failure Research, Section of Cardiology, Department of Medicine, Baylor College of Medicine, Houston, TX (G.D.S., W.W.)
| | - Gabor D Szalai
- From the Cardiovascular Division, Department of Medicine, Washington University School of Medicine, St. Louis, MO (J.H., X.M., A.D., D.L.M.); John Cochran VA Medical Center, St. Louis, MO (A.D.); and Winters Center for Heart Failure Research, Section of Cardiology, Department of Medicine, Baylor College of Medicine, Houston, TX (G.D.S., W.W.)
| | - Wei Wang
- From the Cardiovascular Division, Department of Medicine, Washington University School of Medicine, St. Louis, MO (J.H., X.M., A.D., D.L.M.); John Cochran VA Medical Center, St. Louis, MO (A.D.); and Winters Center for Heart Failure Research, Section of Cardiology, Department of Medicine, Baylor College of Medicine, Houston, TX (G.D.S., W.W.)
| | - Xiucui Ma
- From the Cardiovascular Division, Department of Medicine, Washington University School of Medicine, St. Louis, MO (J.H., X.M., A.D., D.L.M.); John Cochran VA Medical Center, St. Louis, MO (A.D.); and Winters Center for Heart Failure Research, Section of Cardiology, Department of Medicine, Baylor College of Medicine, Houston, TX (G.D.S., W.W.)
| | - Abhinav Diwan
- From the Cardiovascular Division, Department of Medicine, Washington University School of Medicine, St. Louis, MO (J.H., X.M., A.D., D.L.M.); John Cochran VA Medical Center, St. Louis, MO (A.D.); and Winters Center for Heart Failure Research, Section of Cardiology, Department of Medicine, Baylor College of Medicine, Houston, TX (G.D.S., W.W.)
| | - Douglas L Mann
- From the Cardiovascular Division, Department of Medicine, Washington University School of Medicine, St. Louis, MO (J.H., X.M., A.D., D.L.M.); John Cochran VA Medical Center, St. Louis, MO (A.D.); and Winters Center for Heart Failure Research, Section of Cardiology, Department of Medicine, Baylor College of Medicine, Houston, TX (G.D.S., W.W.).
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110
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Ferreiro A, Andoni Urtizberea J. [Titin-related muscle disorders: an expanding spectrum]. Med Sci (Paris) 2017; 33 Hors série n°1:16-26. [PMID: 29139381 DOI: 10.1051/medsci/201733s104] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Titin-related diseases of the skeletal and cardiac muscles open a new, fruitful chapter of myology. Confined for a long time to a limited number of clinical entities, the phenotypic spectrum of titinopthies is nowadays expanding rapidly together with the discovery of many pathogenic mutations of the TTN gene. Like for many genes of large size, the fine tuning and use of high-throughput sequencing (NGS) constitutes a little revolution in the field. This powerful tool allows, although with real technical hurdles, the establishment of the definite diagnosis of titinopathy. A better knowledge of the natural history of each subtype of titinopathy enables as of now an optimized management of patients, notably when a cardiac or respiratory risk factor is identified. Research efforts in the titin-related conditions are gradually getting organized. Interactions between clinicians and geneticists are an absolute necessity. The still fragmentary knowledge of the pathogenesis of each titinopathy prevents to date to figure out any curative therapy in the very near future.
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Affiliation(s)
- Ana Ferreiro
- Pathophysiology of Striated Muscles laboratory, Unit of Functional and Adaptive Biology, BFA, University Paris Diderot/CNRS, Sorbonne Paris Cité, Paris, France - AP-HP, Centre de Référence Maladies Neuromusculaires Paris-Est, Groupe Hospitalier Pitié-Salpêtrière, 75013, Paris, France
| | - J Andoni Urtizberea
- Centre de compétence neuromusculaire Filnemus/Hôpital Marin, Hendaye, France
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111
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Ehsan M, Jiang H, L Thomson K, Gehmlich K. When signalling goes wrong: pathogenic variants in structural and signalling proteins causing cardiomyopathies. J Muscle Res Cell Motil 2017; 38:303-316. [PMID: 29119312 PMCID: PMC5742121 DOI: 10.1007/s10974-017-9487-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Accepted: 10/28/2017] [Indexed: 12/20/2022]
Abstract
Cardiomyopathies are a diverse group of cardiac disorders with distinct phenotypes, depending on the proteins and pathways affected. A substantial proportion of cardiomyopathies are inherited and those will be the focus of this review article. With the wide application of high-throughput sequencing in the practice of clinical genetics, the roles of novel genes in cardiomyopathies are recognised. Here, we focus on a subgroup of cardiomyopathy genes [TTN, FHL1, CSRP3, FLNC and PLN, coding for Titin, Four and a Half LIM domain 1, Muscle LIM Protein, Filamin C and Phospholamban, respectively], which, despite their diverse biological functions, all have important signalling functions in the heart, suggesting that disturbances in signalling networks can contribute to cardiomyopathies.
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Affiliation(s)
- Mehroz Ehsan
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine and British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, UK
| | - He Jiang
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine and British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, UK
| | - Kate L Thomson
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine and British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, UK
| | - Katja Gehmlich
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine and British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, UK.
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112
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Tarnovskaya S, Kiselev A, Kostareva A, Frishman D. Structural consequences of mutations associated with idiopathic restrictive cardiomyopathy. Amino Acids 2017; 49:1815-1829. [DOI: 10.1007/s00726-017-2480-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Accepted: 08/12/2017] [Indexed: 02/02/2023]
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113
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The secret life of kinases: insights into non-catalytic signalling functions from pseudokinases. Biochem Soc Trans 2017; 45:665-681. [PMID: 28620028 DOI: 10.1042/bst20160331] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Revised: 03/08/2017] [Accepted: 03/09/2017] [Indexed: 12/31/2022]
Abstract
Over the past decade, our understanding of the mechanisms by which pseudokinases, which comprise ∼10% of the human and mouse kinomes, mediate signal transduction has advanced rapidly with increasing structural, biochemical, cellular and genetic studies. Pseudokinases are the catalytically defective counterparts of conventional, active protein kinases and have been attributed functions as protein interaction domains acting variously as allosteric modulators of conventional protein kinases and other enzymes, as regulators of protein trafficking or localisation, as hubs to nucleate assembly of signalling complexes, and as transmembrane effectors of such functions. Here, by categorising mammalian pseudokinases based on their known functions, we illustrate the mechanistic diversity among these proteins, which can be viewed as a window into understanding the non-catalytic functions that can be exerted by conventional protein kinases.
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114
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Randazzo D, Pierantozzi E, Rossi D, Sorrentino V. The potential of obscurin as a therapeutic target in muscle disorders. Expert Opin Ther Targets 2017; 21:897-910. [DOI: 10.1080/14728222.2017.1361931] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Davide Randazzo
- Light Imaging Section, Office of Science and Technology, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda
| | - Enrico Pierantozzi
- Molecular Medicine Section, Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
| | - Daniela Rossi
- Molecular Medicine Section, Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
| | - Vincenzo Sorrentino
- Molecular Medicine Section, Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
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115
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Shen Y, Cheng Y, Uyeda TQP, Plaza GR. Cell Mechanosensors and the Possibilities of Using Magnetic Nanoparticles to Study Them and to Modify Cell Fate. Ann Biomed Eng 2017; 45:2475-2486. [PMID: 28744841 DOI: 10.1007/s10439-017-1884-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2017] [Accepted: 07/07/2017] [Indexed: 12/13/2022]
Abstract
The use of magnetic nanoparticles (MNPs) is a promising technique for future advances in biomedical applications. This idea is supported by the availability of MNPs that can target specific cell components, the variety of shapes of MNPs and the possibility of finely controlling the applied magnetic forces. To examine this opportunity, here we review the current developments in the use of MNPs to mechanically stimulate cells and, specifically, the cell mechanotransduction systems. We analyze the cell components that may act as mechanosensors and their effect on cell fate and we focus on the promising possibilities of controlling stem-cell differentiation, inducing cancer-cell death and treating nervous-system diseases.
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Affiliation(s)
- Yajing Shen
- The Institute for Translational Nanomedicine, Shanghai East Hospital, The Institute for Biomedical Engineering & Nano Science, Tongji University School of Medicine, Shanghai, 200120, China
| | - Yu Cheng
- The Institute for Translational Nanomedicine, Shanghai East Hospital, The Institute for Biomedical Engineering & Nano Science, Tongji University School of Medicine, Shanghai, 200120, China.
| | - Taro Q P Uyeda
- The Institute for Translational Nanomedicine, Shanghai East Hospital, The Institute for Biomedical Engineering & Nano Science, Tongji University School of Medicine, Shanghai, 200120, China.,Department of Physics, Faculty of Science and Engineering, Waseda University, Tokyo, 169-8555, Japan
| | - Gustavo R Plaza
- The Institute for Translational Nanomedicine, Shanghai East Hospital, The Institute for Biomedical Engineering & Nano Science, Tongji University School of Medicine, Shanghai, 200120, China. .,Center for Biomedical Technology, Universidad Politécnica de Madrid, 28223, Pozuelo de Alarcón, Spain.
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116
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Koskinen SOA, Kyröläinen H, Flink R, Selänne HP, Gagnon SS, Ahtiainen JP, Nindl BC, Lehti M. Human skeletal muscle type 1 fibre distribution and response of stress-sensing proteins along the titin molecule after submaximal exhaustive exercise. Histochem Cell Biol 2017; 148:545-555. [PMID: 28712031 DOI: 10.1007/s00418-017-1595-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/08/2017] [Indexed: 01/05/2023]
Abstract
Early responses of stress-sensing proteins, muscle LIM protein (MLP), ankyrin repeat proteins (Ankrd1/CARP and Ankrd2/Arpp) and muscle-specific RING finger proteins (MuRF1 and MuRF2), along the titin molecule were investigated in the present experiment after submaximal exhaustive exercise. Ten healthy men performed continuous drop jumping unilaterally on a sledge apparatus with a submaximal height until complete exhaustion. Five stress-sensing proteins were analysed by mRNA measurements from biopsies obtained immediately and 3 h after the exercise from exercised vastus lateralis muscle while control biopsies were obtained from non-exercised legs before the exercise. Decreased maximal jump height and increased serum creatine kinase activities as indirect markers for muscle damage and HSP27 immunostainings on muscle biopsies as a direct marker for muscle damage indicated that the current exercised protocol caused muscle damage. mRNA levels for four (MLP, Ankrd1/CARP, MuRF1 and MuRF2) out of the five studied stress sensors significantly (p < 0.05) increased 3 h after fatiguing exercise. The magnitude of MLP and Ankrd2 responses was related to the proportion of type 1 myofibres. Our data showed that the submaximal exhaustive exercise with subject's own physical fitness level activates titin-based stretch-sensing proteins. These results suggest that both degenerative and regenerative pathways are activated in very early phase after the exercise or probably already during the exercise. Activation of these proteins represents an initial step forward adaptive remodelling of the exercised muscle and may also be involved in the initiation of myofibre repair.
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Affiliation(s)
- Satu O A Koskinen
- LIKES Research Centre for Physical Activity and Health, Rautpohjankatu 8, 40700, Jyväskylä, Finland.
- Unit of Biology of Physical Activity, Faculty of Sport and Health Sciences, University of Jyväskylä, Rautpohjankatu 8, 40700, Jyväskylä, Finland.
| | - Heikki Kyröläinen
- Unit of Biology of Physical Activity, Faculty of Sport and Health Sciences, University of Jyväskylä, Rautpohjankatu 8, 40700, Jyväskylä, Finland
| | - Riina Flink
- Unit of Biology of Physical Activity, Faculty of Sport and Health Sciences, University of Jyväskylä, Rautpohjankatu 8, 40700, Jyväskylä, Finland
| | - Harri P Selänne
- Department of Psychology, University of Jyväskylä, Alvar Aallon katu 9, 40600, Jyväskylä, Finland
- Hospital Mehiläinen, Sports Injury Clinic, Pohjoinen Hesperiankatu 17 C, 00260, Helsinki, Finland
| | - Sheila S Gagnon
- Wolf Orthopaedic Biomechanics Laboratory, Fowler Kennedy Sport Medicine Clinic, University of Western Ontario, London, Canada
| | - Juha P Ahtiainen
- Unit of Biology of Physical Activity, Faculty of Sport and Health Sciences, University of Jyväskylä, Rautpohjankatu 8, 40700, Jyväskylä, Finland
| | - Bradley C Nindl
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, University of Pittsburgh, 3860 South Water Street, Pittsburgh, PA, 15203, USA
| | - Maarit Lehti
- LIKES Research Centre for Physical Activity and Health, Rautpohjankatu 8, 40700, Jyväskylä, Finland
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117
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Brown DI, Parry TL, Willis MS. Ubiquitin Ligases and Posttranslational Regulation of Energy in the Heart: The Hand that Feeds. Compr Physiol 2017. [PMID: 28640445 DOI: 10.1002/cphy.c160024] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Heart failure (HF) is a costly and deadly syndrome characterized by the reduced capacity of the heart to adequately provide systemic blood flow. Mounting evidence implicates pathological changes in cardiac energy metabolism as a contributing factor in the development of HF. While the main source of fuel in the healthy heart is the oxidation of fatty acids, in the failing heart the less energy efficient glucose and glycogen metabolism are upregulated. The ubiquitin proteasome system plays a key role in regulating metabolism via protein-degradation/regulation of autophagy and regulating metabolism-related transcription and cell signaling processes. In this review, we discuss recent research that describes the role of the ubiquitin-proteasome system (UPS) in regulating metabolism in the context of HF. We focus on ubiquitin ligases (E3s), the component of the UPS that confers substrate specificity, and detail the current understanding of how these E3s contribute to cardiac pathology and metabolism. © 2017 American Physiological Society. Compr Physiol 7:841-862, 2017.
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Affiliation(s)
- David I Brown
- McAllister Heart Institute, University of North Carolina, Chapel Hill, North Carolina, USA.,Department of Pathology & Laboratory Medicine, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Traci L Parry
- McAllister Heart Institute, University of North Carolina, Chapel Hill, North Carolina, USA.,Department of Pathology & Laboratory Medicine, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Monte S Willis
- McAllister Heart Institute, University of North Carolina, Chapel Hill, North Carolina, USA.,Department of Pathology & Laboratory Medicine, University of North Carolina, Chapel Hill, North Carolina, USA.,Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina, USA
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118
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Genetic epidemiology of titin-truncating variants in the etiology of dilated cardiomyopathy. Biophys Rev 2017; 9:207-223. [PMID: 28510119 PMCID: PMC5498329 DOI: 10.1007/s12551-017-0265-7] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Accepted: 04/10/2017] [Indexed: 02/07/2023] Open
Abstract
Heart failure (HF) is a complex clinical syndrome defined by the inability of the heart to pump enough blood to meet the body's metabolic demands. Major causes of HF are cardiomyopathies (diseases of the myocardium associated with mechanical and/or electrical dysfunction), among which the most common form is dilated cardiomyopathy (DCM). DCM is defined by ventricular chamber enlargement and systolic dysfunction with normal left ventricular wall thickness, which leads to progressive HF. Over 60 genes are linked to the etiology of DCM. Titin (TTN) is the largest known protein in biology, spanning half the cardiac sarcomere and, as such, is a basic structural and functional unit of striated muscles. It is essential for heart development as well as mechanical and regulatory functions of the sarcomere. Next-generation sequencing (NGS) in clinical DCM cohorts implicated truncating variants in titin (TTNtv) as major disease alleles, accounting for more than 25% of familial DCM cases, but these variants have also been identified in 2-3% of the general population, where these TTNtv blur diagnostic and clinical utility. Taking into account the published TTNtv and their association to DCM, it becomes clear that TTNtv harm the heart with position-dependent occurrence, being more harmful when present in the A-band TTN, presumably with dominant negative/gain-of-function mechanisms. However, these insights are challenged by the depiction of position-independent toxicity of TTNtv acting via haploinsufficient alleles, which are sufficient to induce cardiac pathology upon stress. In the current review, we provide an overview of TTN and discuss studies investigating various TTN mutations. We also present an overview of different mechanisms postulated or experimentally validated in the pathogenicity of TTNtv. DCM-causing genes are also discussed with respect to non-truncating mutations in the etiology of DCM. One way of understanding pathogenic variants is probably to understand the context in which they may or may not affect protein-protein interactions, changes in cell signaling, and substrate specificity. In this regard, we also provide a brief overview of TTN interactions in situ. Quantitative models in the risk assessment of TTNtv are also discussed. In summary, we highlight the importance of gene-environment interactions in the etiology of DCM and further mechanistic studies used to delineate the pathways which could be targeted in the management of DCM.
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119
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Matsunaga Y, Hwang H, Franke B, Williams R, Penley M, Qadota H, Yi H, Morran LT, Lu H, Mayans O, Benian GM. Twitchin kinase inhibits muscle activity. Mol Biol Cell 2017; 28:1591-1600. [PMID: 28428253 PMCID: PMC5469603 DOI: 10.1091/mbc.e16-10-0707] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Revised: 04/04/2017] [Accepted: 04/11/2017] [Indexed: 01/03/2023] Open
Abstract
Muscles express giant polypeptides with kinase domains, but the in vivo significance of their catalytic activity has been unknown. Analysis of a mutant nematode that expresses the giant protein twitchin with a catalytically inactive kinase indicates that twitchin kinase inhibits muscle activity and is favored by selection. Muscle sarcomeres contain giant polypeptides composed of multiple immunoglobulin and fibronectin domains and one or two protein kinase domains. Although binding partners for a number of this family’s kinase domains have been identified, the catalytic necessity of these kinase domains remains unknown. In addition, various members of this kinase family are suspected pseudokinases with no or little activity. Here we address catalytic necessity for the first time, using the prototypic invertebrate representative twitchin (UNC-22) from Caenorhabditis elegans. In in vitro experiments, change of a conserved lysine (K) that is involved in ATP coordination to alanine (A) resulted in elimination of kinase activity without affecting the overall structure of the kinase domain. The same mutation, unc-22(sf21), was generated in the endogenous twitchin gene. The unc-22(sf21) worms have well-organized sarcomeres. However, unc-22(sf21) mutants move faster than wild-type worms and, by optogenetic experiments, contract more. Wild-type nematodes exhibited greater competitive fitness than unc-22(sf21) mutants. Thus the catalytic activity of twitchin kinase has a role in vivo, where it inhibits muscle activity and is likely maintained by selection.
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Affiliation(s)
- Yohei Matsunaga
- Department of Pathology, Emory University, Atlanta, GA 30322
| | - Hyundoo Hwang
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA 30332
| | - Barbara Franke
- Department of Biology, University of Konstanz, 78457 Konstanz, Germany
| | - Rhys Williams
- Department of Biology, University of Konstanz, 78457 Konstanz, Germany
| | - McKenna Penley
- Department of Biology, Emory University, Atlanta, GA 30322
| | - Hiroshi Qadota
- Department of Pathology, Emory University, Atlanta, GA 30322
| | - Hong Yi
- Apkarian Integrated Electron Microscopy Core, Emory University, Atlanta, GA 30322
| | - Levi T Morran
- Department of Biology, Emory University, Atlanta, GA 30322
| | - Hang Lu
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA 30332
| | - Olga Mayans
- Department of Biology, University of Konstanz, 78457 Konstanz, Germany
| | - Guy M Benian
- Department of Pathology, Emory University, Atlanta, GA 30322
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120
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Tampering with springs: phosphorylation of titin affecting the mechanical function of cardiomyocytes. Biophys Rev 2017; 9:225-237. [PMID: 28510118 PMCID: PMC5498327 DOI: 10.1007/s12551-017-0263-9] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Accepted: 03/26/2017] [Indexed: 12/17/2022] Open
Abstract
Reversible post-translational modifications of various cardiac proteins regulate the mechanical properties of the cardiomyocytes and thus modulate the contractile performance of the heart. The giant protein titin forms a continuous filament network in the sarcomeres of striated muscle cells, where it determines passive tension development and modulates active contraction. These mechanical properties of titin are altered through post-translational modifications, particularly phosphorylation. Titin contains hundreds of potential phosphorylation sites, the functional relevance of which is only beginning to emerge. Here, we provide a state-of-the-art summary of the phosphorylation sites in titin, with a particular focus on the elastic titin spring segment. We discuss how phosphorylation at specific amino acids can reduce or increase the stretch-induced spring force of titin, depending on where the spring region is phosphorylated. We also review which protein kinases phosphorylate titin and how this phosphorylation affects titin-based passive tension in cardiomyocytes. A comprehensive overview is provided of studies that have measured altered titin phosphorylation and titin-based passive tension in myocardial samples from human heart failure patients and animal models of heart disease. As our understanding of the broader implications of phosphorylation in titin progresses, this knowledge could be used to design targeted interventions aimed at reducing pathologically increased titin stiffness in patients with stiff hearts.
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121
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Cerino M, Gorokhova S, Laforet P, Ben Yaou R, Salort-Campana E, Pouget J, Attarian S, Eymard B, Deleuze JF, Boland A, Behin A, Stojkovic T, Bonne G, Levy N, Bartoli M, Krahn M. Genetic Characterization of a French Cohort of GNE-mutation negative inclusion body myopathy patients with exome sequencing. Muscle Nerve 2017; 56:993-997. [PMID: 28256728 DOI: 10.1002/mus.25638] [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] [Accepted: 02/26/2017] [Indexed: 12/30/2022]
Abstract
INTRODUCTION Hereditary inclusion body myopathy (hIBM) refers to a group of clinically and genetically heterogeneous diseases. The overlapping histochemical features of hIBM with other genetic disorders lead to low diagnostic rates with targeted single-gene sequencing. This is true for the most prevalent form of hIBM, GNEpathy. Therefore, we used whole-exome sequencing (WES) to determine whether a cohort of clinically suspected GNEpathy patients undiagnosed by targeted GNE analysis could be genetically characterized. METHODS Twenty patients with hIBM but undiagnosed by targeted GNE sequencing were analyzed by WES before data filtering on 306 genes associated with neuromuscular disorders. RESULTS Seven patients out of 20 were found to have disease-causing mutations in genes associated with hIBM or genes allowing for hIBM in the differential diagnosis or associated with unexpected diagnosis. DISCUSSION Next-generation sequencing is an efficient strategy in the context of hIBM, resulting in a molecular diagnosis for 35% of the patients initially undiagnosed by targeted GNE analysis. Muscle Nerve 56: 993-997, 2017.
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Affiliation(s)
- Mathieu Cerino
- Aix Marseille University, GMGF, INSERM AMU UMR_S910, Faculté de Médecine de Marseille, 4e étage Aile Verte, 27 Boulevard Jean Moulin, 13385, Marseille Cedex 05, France.,APHM, Hôpital Timone Enfants, Département de Génétique Médicale, Marseille, France
| | - Svetlana Gorokhova
- Aix Marseille University, GMGF, INSERM AMU UMR_S910, Faculté de Médecine de Marseille, 4e étage Aile Verte, 27 Boulevard Jean Moulin, 13385, Marseille Cedex 05, France
| | - Pascal Laforet
- APHP, G.H. Pitié Salpêtrière, Centre de Référence Maladies Neuromusculaires Paris-Est, Institut de Myologie, Paris, France
| | - Rabah Ben Yaou
- APHP, G.H. Pitié Salpêtrière, Centre de Référence Maladies Neuromusculaires Paris-Est, Institut de Myologie, Paris, France.,Sorbonne Universités, UPMC University of Paris 06, Inserm UMRS974, CNRS FRE3617, Center for Research in Myology, Institut de Myologie, G.H. Pitié Salpêtrière, Paris, France
| | - Emmanuelle Salort-Campana
- Aix Marseille University, GMGF, INSERM AMU UMR_S910, Faculté de Médecine de Marseille, 4e étage Aile Verte, 27 Boulevard Jean Moulin, 13385, Marseille Cedex 05, France.,APHM, Hôpital La Timone, Centre de Référence des Maladies Neuromusculaires et de la SLA, Marseille, France
| | - Jean Pouget
- Aix Marseille University, GMGF, INSERM AMU UMR_S910, Faculté de Médecine de Marseille, 4e étage Aile Verte, 27 Boulevard Jean Moulin, 13385, Marseille Cedex 05, France.,APHM, Hôpital La Timone, Centre de Référence des Maladies Neuromusculaires et de la SLA, Marseille, France
| | - Shahram Attarian
- Aix Marseille University, GMGF, INSERM AMU UMR_S910, Faculté de Médecine de Marseille, 4e étage Aile Verte, 27 Boulevard Jean Moulin, 13385, Marseille Cedex 05, France.,APHM, Hôpital La Timone, Centre de Référence des Maladies Neuromusculaires et de la SLA, Marseille, France
| | - Bruno Eymard
- APHP, G.H. Pitié Salpêtrière, Centre de Référence Maladies Neuromusculaires Paris-Est, Institut de Myologie, Paris, France
| | | | - Anne Boland
- Centre National de Génotypage, Institut de Génomique, CEA, Evry, France
| | - Anthony Behin
- APHP, G.H. Pitié Salpêtrière, Centre de Référence Maladies Neuromusculaires Paris-Est, Institut de Myologie, Paris, France
| | - Tanya Stojkovic
- APHP, G.H. Pitié Salpêtrière, Centre de Référence Maladies Neuromusculaires Paris-Est, Institut de Myologie, Paris, France
| | - Gisele Bonne
- Sorbonne Universités, UPMC University of Paris 06, Inserm UMRS974, CNRS FRE3617, Center for Research in Myology, Institut de Myologie, G.H. Pitié Salpêtrière, Paris, France
| | - Nicolas Levy
- Aix Marseille University, GMGF, INSERM AMU UMR_S910, Faculté de Médecine de Marseille, 4e étage Aile Verte, 27 Boulevard Jean Moulin, 13385, Marseille Cedex 05, France.,APHM, Hôpital Timone Enfants, Département de Génétique Médicale, Marseille, France
| | - Marc Bartoli
- Aix Marseille University, GMGF, INSERM AMU UMR_S910, Faculté de Médecine de Marseille, 4e étage Aile Verte, 27 Boulevard Jean Moulin, 13385, Marseille Cedex 05, France.,APHM, Hôpital Timone Enfants, Département de Génétique Médicale, Marseille, France
| | - Martin Krahn
- Aix Marseille University, GMGF, INSERM AMU UMR_S910, Faculté de Médecine de Marseille, 4e étage Aile Verte, 27 Boulevard Jean Moulin, 13385, Marseille Cedex 05, France.,APHM, Hôpital Timone Enfants, Département de Génétique Médicale, Marseille, France
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122
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Nakano S, Oki M, Kusaka H. The role of p62/SQSTM1 in sporadic inclusion body myositis. Neuromuscul Disord 2017; 27:363-369. [DOI: 10.1016/j.nmd.2016.12.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Revised: 11/22/2016] [Accepted: 12/12/2016] [Indexed: 10/20/2022]
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123
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Mechanical forces during muscle development. Mech Dev 2017; 144:92-101. [DOI: 10.1016/j.mod.2016.11.003] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2016] [Revised: 11/20/2016] [Accepted: 11/21/2016] [Indexed: 01/09/2023]
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124
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Hatakeyama S. TRIM Family Proteins: Roles in Autophagy, Immunity, and Carcinogenesis. Trends Biochem Sci 2017; 42:297-311. [DOI: 10.1016/j.tibs.2017.01.002] [Citation(s) in RCA: 561] [Impact Index Per Article: 80.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Revised: 12/28/2016] [Accepted: 01/02/2017] [Indexed: 01/19/2023]
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125
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Schuelke M, Øien NC, Oldfors A. Myopathology in the times of modern genetics. Neuropathol Appl Neurobiol 2017; 43:44-61. [DOI: 10.1111/nan.12374] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Revised: 12/03/2016] [Accepted: 12/23/2016] [Indexed: 12/14/2022]
Affiliation(s)
- M. Schuelke
- Department of Neuropediatrics and NeuroCure Clinical Research Center; Charité-Universitätsmedizin; Berlin Germany
| | - N. C. Øien
- Department of Neuropediatrics and NeuroCure Clinical Research Center; Charité-Universitätsmedizin; Berlin Germany
- Max-Delbrück-Center for Molecular Medicine; Berlin Germany
| | - A. Oldfors
- Department of Pathology and Genetics; Institute of Biomedicine; University of Gothenburg; Gothenburg Sweden
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126
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Esslinger U, Garnier S, Korniat A, Proust C, Kararigas G, Müller-Nurasyid M, Empana JP, Morley MP, Perret C, Stark K, Bick AG, Prasad SK, Kriebel J, Li J, Tiret L, Strauch K, O'Regan DP, Marguiles KB, Seidman JG, Boutouyrie P, Lacolley P, Jouven X, Hengstenberg C, Komajda M, Hakonarson H, Isnard R, Arbustini E, Grallert H, Cook SA, Seidman CE, Regitz-Zagrosek V, Cappola TP, Charron P, Cambien F, Villard E. Exome-wide association study reveals novel susceptibility genes to sporadic dilated cardiomyopathy. PLoS One 2017; 12:e0172995. [PMID: 28296976 PMCID: PMC5351854 DOI: 10.1371/journal.pone.0172995] [Citation(s) in RCA: 83] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Accepted: 02/13/2017] [Indexed: 12/11/2022] Open
Abstract
Aims Dilated cardiomyopathy (DCM) is an important cause of heart failure with a strong familial component. We performed an exome-wide array-based association study (EWAS) to assess the contribution of missense variants to sporadic DCM. Methods and results 116,855 single nucleotide variants (SNVs) were analyzed in 2796 DCM patients and 6877 control subjects from 6 populations of European ancestry. We confirmed two previously identified associations with SNVs in BAG3 and ZBTB17 and discovered six novel DCM-associated loci (Q-value<0.01). The lead-SNVs at novel loci are common and located in TTN, SLC39A8, MLIP, FLNC, ALPK3 and FHOD3. In silico fine mapping identified HSPB7 as the most likely candidate at the ZBTB17 locus. Rare variant analysis (MAF<0.01) demonstrated significant association for TTN variants only (P = 0.0085). All candidate genes but one (SLC39A8) exhibit preferential expression in striated muscle tissues and mutations in TTN, BAG3, FLNC and FHOD3 are known to cause familial cardiomyopathy. We also investigated a panel of 48 known cardiomyopathy genes. Collectively, rare (n = 228, P = 0.0033) or common (n = 36, P = 0.019) variants with elevated in silico severity scores were associated with DCM, indicating that the spectrum of genes contributing to sporadic DCM extends beyond those identified here. Conclusion We identified eight loci independently associated with sporadic DCM. The functions of the best candidate genes at these loci suggest that proteostasis regulation might play a role in DCM pathophysiology.
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Affiliation(s)
- Ulrike Esslinger
- Sorbonne Universités, UPMC Univ Paris 06, INSERM UMR-S1166, Team Genomics & Pathophysiology of Cardiovascular Diseases, Paris, France
- ICAN Institute for Cardiometabolism and Nutrition, Paris, France
| | - Sophie Garnier
- Sorbonne Universités, UPMC Univ Paris 06, INSERM UMR-S1166, Team Genomics & Pathophysiology of Cardiovascular Diseases, Paris, France
- ICAN Institute for Cardiometabolism and Nutrition, Paris, France
| | - Agathe Korniat
- Sorbonne Universités, UPMC Univ Paris 06, INSERM UMR-S1166, Team Genomics & Pathophysiology of Cardiovascular Diseases, Paris, France
- ICAN Institute for Cardiometabolism and Nutrition, Paris, France
| | - Carole Proust
- Sorbonne Universités, UPMC Univ Paris 06, INSERM UMR-S1166, Team Genomics & Pathophysiology of Cardiovascular Diseases, Paris, France
- ICAN Institute for Cardiometabolism and Nutrition, Paris, France
| | - Georgios Kararigas
- Institute of Gender in Medicine and Center for Cardiovascular Research, Charite University Hospital, and DZHK, Berlin, Germany
| | - Martina Müller-Nurasyid
- Institute of Genetic Epidemiology, Helmholtz Zentrum München—German Research Center for Environmental Health, Neuherberg, Germany
- Department of Medicine I, Ludwig-Maximilians-University Munich, Munich, Germany
- DZHK (German Centre for Cardiovascular Research), Partnersite Munich Heart Alliance, Munich, Germany
| | - Jean-Philippe Empana
- INSERM, UMR-S970, Department of Epidemiology, Paris, France
- Université Paris Descartes, Sorbonne Paris Cité, Faculté de Médecine, Paris, France
| | - Michael P. Morley
- Penn Cardiovascular Institute and Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States of America
| | - Claire Perret
- Sorbonne Universités, UPMC Univ Paris 06, INSERM UMR-S1166, Team Genomics & Pathophysiology of Cardiovascular Diseases, Paris, France
- ICAN Institute for Cardiometabolism and Nutrition, Paris, France
| | - Klaus Stark
- Department of Genetic Epidemiology, University of Regensburg, Regensburg, Germany
| | - Alexander G. Bick
- Department of Medecine and Genetics Harvard Medical School, Boston, MA, United States of America
| | | | - Jennifer Kriebel
- Research Unit of Molecular Epidemiology, Helmholtz Zentrum München—German Research Center for Environmental Health, Neuherberg, Germany
- Institute of Epidemiology II, Helmholtz Zentrum München—German Research Center for Environmental Health, Neuherberg, Germany
- German Center for Diabetes Research, Neuherberg, Germany
| | - Jin Li
- Center for Applied Genomics, Children’s Hospital of Philadelphia, Philadelphia, PA, United States of America
| | - Laurence Tiret
- Sorbonne Universités, UPMC Univ Paris 06, INSERM UMR-S1166, Team Genomics & Pathophysiology of Cardiovascular Diseases, Paris, France
- ICAN Institute for Cardiometabolism and Nutrition, Paris, France
| | - Konstantin Strauch
- Institute of Genetic Epidemiology, Helmholtz Zentrum München—German Research Center for Environmental Health, Neuherberg, Germany
- Institute of Medical Informatics, Biometry and Epidemiology, Chair of Genetic Epidemiology, Ludwig-Maximilians-Universität, Munich, Germany
| | - Declan P. O'Regan
- Medical Research Council Clinical Sciences Centre, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Kenneth B. Marguiles
- Penn Cardiovascular Institute and Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States of America
| | - Jonathan G. Seidman
- Department of Medecine and Genetics Harvard Medical School, Boston, MA, United States of America
- Howard Hughes Medical Institute, Chevy Chase, MD, United States of America
| | - Pierre Boutouyrie
- INSERM, UMR-S970, Department of Epidemiology, Paris, France
- Université Paris Descartes, Sorbonne Paris Cité, Faculté de Médecine, Paris, France
- AP-HP, Georges Pompidou European Hospital, Pharmacology Department, Paris, France
| | | | - Xavier Jouven
- INSERM, UMR-S970, Department of Epidemiology, Paris, France
- Université Paris Descartes, Sorbonne Paris Cité, Faculté de Médecine, Paris, France
- AP-HP, Georges Pompidou European Hospital, Cardiology Department, Paris, France
| | - Christian Hengstenberg
- DZHK (German Centre for Cardiovascular Research), Partnersite Munich Heart Alliance, Munich, Germany
- Deutsches Herzzentrum München, Technische Universität München, Munich, Germany
| | - Michel Komajda
- Sorbonne Universités, UPMC Univ Paris 06, INSERM UMR-S1166, Team Genomics & Pathophysiology of Cardiovascular Diseases, Paris, France
- ICAN Institute for Cardiometabolism and Nutrition, Paris, France
- AP-HP, Pitié-Salpêtrière Hospital, Cardiology Department, Paris, France
- AP-HP, Hôpital Pitié-Salpêtrière, Centre de Référence des Maladies Cardiaques Héréditaires, Paris, France
| | - Hakon Hakonarson
- Center for Applied Genomics, Children’s Hospital of Philadelphia, Philadelphia, PA, United States of America
| | - Richard Isnard
- Sorbonne Universités, UPMC Univ Paris 06, INSERM UMR-S1166, Team Genomics & Pathophysiology of Cardiovascular Diseases, Paris, France
- ICAN Institute for Cardiometabolism and Nutrition, Paris, France
- AP-HP, Pitié-Salpêtrière Hospital, Cardiology Department, Paris, France
- AP-HP, Hôpital Pitié-Salpêtrière, Centre de Référence des Maladies Cardiaques Héréditaires, Paris, France
| | | | - Harald Grallert
- Research Unit of Molecular Epidemiology, Helmholtz Zentrum München—German Research Center for Environmental Health, Neuherberg, Germany
- Institute of Epidemiology II, Helmholtz Zentrum München—German Research Center for Environmental Health, Neuherberg, Germany
- German Center for Diabetes Research, Neuherberg, Germany
| | - Stuart A. Cook
- National Heart Centre Singapore, Singapore
- National Heart and Lung Institute, Imperial College London, London, United Kingdom
- Duke-NUS, Singapore
| | - Christine E. Seidman
- Department of Medecine and Genetics Harvard Medical School, Boston, MA, United States of America
- Howard Hughes Medical Institute, Chevy Chase, MD, United States of America
| | - Vera Regitz-Zagrosek
- Institute of Gender in Medicine and Center for Cardiovascular Research, Charite University Hospital, and DZHK, Berlin, Germany
| | - Thomas P. Cappola
- Penn Cardiovascular Institute and Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States of America
| | - Philippe Charron
- Sorbonne Universités, UPMC Univ Paris 06, INSERM UMR-S1166, Team Genomics & Pathophysiology of Cardiovascular Diseases, Paris, France
- ICAN Institute for Cardiometabolism and Nutrition, Paris, France
- AP-HP, Pitié-Salpêtrière Hospital, Cardiology Department, Paris, France
- AP-HP, Hôpital Pitié-Salpêtrière, Centre de Référence des Maladies Cardiaques Héréditaires, Paris, France
- Université de Versailles-Saint Quentin, AP-HP, Hôpital Ambroise Paré, Boulogne-Billancourt, France
| | - François Cambien
- Sorbonne Universités, UPMC Univ Paris 06, INSERM UMR-S1166, Team Genomics & Pathophysiology of Cardiovascular Diseases, Paris, France
- ICAN Institute for Cardiometabolism and Nutrition, Paris, France
- * E-mail: (EV); (FC)
| | - Eric Villard
- Sorbonne Universités, UPMC Univ Paris 06, INSERM UMR-S1166, Team Genomics & Pathophysiology of Cardiovascular Diseases, Paris, France
- ICAN Institute for Cardiometabolism and Nutrition, Paris, France
- AP-HP, Pitié-Salpêtrière Hospital, Cardiology Department, Paris, France
- * E-mail: (EV); (FC)
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Li M, Andersson-Lendahl M, Sejersen T, Arner A. Knockdown of fast skeletal myosin-binding protein C in zebrafish results in a severe skeletal myopathy. ACTA ACUST UNITED AC 2016; 147:309-22. [PMID: 27022191 PMCID: PMC4810067 DOI: 10.1085/jgp.201511452] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Accepted: 02/26/2016] [Indexed: 12/30/2022]
Abstract
MyBPC: A muscle protein for all seasons. Myosin-binding protein C (MyBPC) in the muscle sarcomere interacts with several contractile and structural proteins. Mutations in the cardiac isoform (MyBPC-3) in humans, or animal knockout, are associated with cardiomyopathy. Function of the fast skeletal isoform (MyBPC-2) in living muscles is less understood. This question was addressed using zebrafish models, combining gene expression data with functional analysis of contractility and small-angle x-ray diffraction measurements of filament structure. Fast skeletal MyBPC-2B, the major isoform, was knocked down by >50% using morpholino antisense nucleotides. These morphants exhibited a skeletal myopathy with elevated apoptosis and up-regulation of factors associated with muscle protein degradation. Morphant muscles had shorter sarcomeres with a broader length distribution, shorter actin filaments, and a wider interfilament spacing compared with controls, suggesting that fast skeletal MyBPC has a role in sarcomere assembly. Active force was reduced more than expected from the decrease in muscle size, suggesting that MyBPC-2 is required for optimal force generation at the cross-bridge level. The maximal shortening velocity was significantly increased in the MyBPC-2 morphants, but when related to the sarcomere length, the difference was smaller, reflecting that the decrease in MyBPC-2B content and the resulting myopathy were accompanied by only a minor influence on filament shortening kinetics. In the controls, equatorial patterns from small-angle x-ray scattering revealed that comparatively few cross-bridges are attached (as evaluated by the intensity ratio of the 11 and 10 equatorial reflections) during active contraction. X-ray scattering data from relaxed and contracting morphants were not significantly different from those in controls. However, the increase in the 11:10 intensity ratio in rigor was lower compared with that in controls, possibly reflecting effects of MyBPC on the cross-bridge interactions. In conclusion, lack of MyBPC-2 results in a severe skeletal myopathy with structural changes and muscle weakness.
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Affiliation(s)
- Mei Li
- Department of Physiology and Pharmacology, Department of Cell and Molecular Biology, and Department of Women's and Children's Health, Karolinska Institutet, SE 171 77 Stockholm, Sweden
| | - Monika Andersson-Lendahl
- Department of Physiology and Pharmacology, Department of Cell and Molecular Biology, and Department of Women's and Children's Health, Karolinska Institutet, SE 171 77 Stockholm, Sweden
| | - Thomas Sejersen
- Department of Physiology and Pharmacology, Department of Cell and Molecular Biology, and Department of Women's and Children's Health, Karolinska Institutet, SE 171 77 Stockholm, Sweden
| | - Anders Arner
- Department of Physiology and Pharmacology, Department of Cell and Molecular Biology, and Department of Women's and Children's Health, Karolinska Institutet, SE 171 77 Stockholm, Sweden
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128
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Gautel M, Djinović-Carugo K. The sarcomeric cytoskeleton: from molecules to motion. ACTA ACUST UNITED AC 2016; 219:135-45. [PMID: 26792323 DOI: 10.1242/jeb.124941] [Citation(s) in RCA: 143] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Highly ordered organisation of striated muscle is the prerequisite for the fast and unidirectional development of force and motion during heart and skeletal muscle contraction. A group of proteins, summarised as the sarcomeric cytoskeleton, is essential for the ordered assembly of actin and myosin filaments into sarcomeres, by combining architectural, mechanical and signalling functions. This review discusses recent cell biological, biophysical and structural insight into the regulated assembly of sarcomeric cytoskeleton proteins and their roles in dissipating mechanical forces in order to maintain sarcomere integrity during passive extension and active contraction. α-Actinin crosslinks in the Z-disk show a pivot-and-rod structure that anchors both titin and actin filaments. In contrast, the myosin crosslinks formed by myomesin in the M-band are of a ball-and-spring type and may be crucial in providing stable yet elastic connections during active contractions, especially eccentric exercise.
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Affiliation(s)
- Mathias Gautel
- King's College London BHF Centre of Research Excellence, Randall Division for Cell and Molecular Biophysics, and Cardiovascular Division, New Hunt's House, London SE1 1UL, UK
| | - Kristina Djinović-Carugo
- Department of Structural and Computational Biology, Max F. Perutz Laboratories, University of Vienna, Campus Vienna Biocenter 5, Vienna A-1030, Austria Department of Biochemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, Aškerčeva 5, Ljubljana 1000, Slovenia
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129
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Abstract
Autophagy, a pathway for lysosomal-mediated cellular degradation, has recently been described as a regulator of cell migration. Although the molecular mechanisms underlying autophagy-dependent motility are only beginning to emerge, new work demonstrates that selective autophagy mediated by the autophagy cargo receptor, NBR1, specifically promotes the dynamic turnover of integrin-based focal adhesion sites during motility. Here, we discuss the detailed mechanisms through which NBR1-dependent selective autophagy supports focal adhesion remodeling, and we describe the interconnections between this pathway and other established regulators of focal adhesion turnover, such as microtubules. We also highlight studies that examine the contribution of autophagy to selective degradation of proteins that mediate cellular tension and to integrin trafficking; these findings hint at further roles for autophagy in supporting adhesion and migration. Given the recently appreciated importance of selective autophagy in diverse cellular processes, we propose that further investigation into autophagy-mediated focal adhesion turnover will not only shed light onto how focal adhesions are regulated but will also unveil new mechanisms regulating selective autophagy.
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Affiliation(s)
- Candia M Kenific
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco, CA 94143, USA Biomedical Sciences Graduate Program, University of California San Francisco, San Francisco, CA 94143, USA
| | - Torsten Wittmann
- Department of Cell and Tissue Biology, University of California San Francisco, San Francisco, CA 94143, USA
| | - Jayanta Debnath
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco, CA 94143, USA
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130
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Evidence for the mechanosensor function of filamin in tissue development. Sci Rep 2016; 6:32798. [PMID: 27597179 PMCID: PMC5011733 DOI: 10.1038/srep32798] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Accepted: 08/15/2016] [Indexed: 12/20/2022] Open
Abstract
Cells integrate mechanical properties of their surroundings to form multicellular, three-dimensional tissues of appropriate size and spatial organisation. Actin cytoskeleton-linked proteins such as talin, vinculin and filamin function as mechanosensors in cells, but it has yet to be tested whether the mechanosensitivity is important for their function in intact tissues. Here we tested, how filamin mechanosensing contributes to oogenesis in Drosophila. Mutations that require more or less force to open the mechanosensor region demonstrate that filamin mechanosensitivity is important for the maturation of actin-rich ring canals that are essential for Drosophila egg development. The open mutant was more tightly bound to the ring canal structure while the closed mutant dissociated more frequently. Thus, our results show that an appropriate level of mechanical sensitivity is required for filamins’ function and dynamics during Drosophila egg growth and support the structure-based model in which the opening and closing of the mechanosensor region regulates filamin binding to cellular components.
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131
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Liu JS, Fan LL, Zhang H, Liu X, Huang H, Tao LJ, Xia K, Xiang R. Whole-Exome Sequencing Identifies Two Novel TTN Mutations in Chinese Families with Dilated Cardiomyopathy. Cardiology 2016; 136:10-14. [PMID: 27544385 DOI: 10.1159/000447422] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Accepted: 06/03/2016] [Indexed: 11/19/2022]
Abstract
OBJECTIVES Dilated cardiomyopathy (DCM) is a leading cause of sudden cardiac death. So far, only 127 mutations of Titin(TTN) have been reported in patients with different phenotypes such as isolated cardiomyopathies, purely skeletal muscle phenotypes or complex overlapping disorders of muscles. METHODS We applied whole-exome sequencing (WES) to investigate cardiomyopathy patients and a cardiomyopathy-related gene-filtering strategy was used to analyze the disease-causing mutations. Sanger sequencing was applied to confirm the mutation cosegregation in the affected families. RESULTS A nonsense mutation (c.12325C>T/p.R4109X) and a missense mutation (c.17755G>C/p.G5919R) of TTN were identified in 2 Chinese DCM families, respectively. Both mutations were cosegregated in all affected members of both families. The nonsense mutation is predicted to result in a truncated TTN protein and the missense mutation leads to a substitution of glycine by arginine. Both variants may cause the structure changes of titin protein. CONCLUSIONS We employed WES to detect the mutations of DCM patients and identified 2 novel mutations. Our study expands the spectrum of TTN mutations and offers accurate genetic testing information for DCM patients who are still clinically negative.
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Affiliation(s)
- Ji-Shi Liu
- The State Key Laboratory of Medical Genetics and School of Life Sciences, Central South University, Changsha, China
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132
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Disrupted autophagy undermines skeletal muscle adaptation and integrity. Mamm Genome 2016; 27:525-537. [PMID: 27484057 PMCID: PMC5110612 DOI: 10.1007/s00335-016-9659-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Accepted: 07/12/2016] [Indexed: 12/18/2022]
Abstract
This review assesses the importance of proteostasis in skeletal muscle maintenance with a specific emphasis on autophagy. Skeletal muscle appears to be particularly vulnerable to genetic defects in basal and induced autophagy, indicating that autophagy is co-substantial to skeletal muscle maintenance and adaptation. We discuss emerging evidence that tension-induced protein unfolding may act as a direct link between mechanical stress and autophagic pathways. Mechanistic links between protein damage, autophagy and muscle hypertrophy, which is also induced by mechanical stress, are still poorly understood. However, some mouse models of muscle disease show ameliorated symptoms upon effective targeting of basal autophagy. These findings highlight the importance of autophagy as therapeutic target and suggest that elucidating connections between protein unfolding and mTOR-dependent or mTOR-independent hypertrophic responses is likely to reveal specific therapeutic windows for the treatment of muscle wasting disorders.
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133
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Gigli M, Begay RL, Morea G, Graw SL, Sinagra G, Taylor MRG, Granzier H, Mestroni L. A Review of the Giant Protein Titin in Clinical Molecular Diagnostics of Cardiomyopathies. Front Cardiovasc Med 2016; 3:21. [PMID: 27493940 PMCID: PMC4954824 DOI: 10.3389/fcvm.2016.00021] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Accepted: 06/27/2016] [Indexed: 12/17/2022] Open
Abstract
Titin (TTN) is known as the largest sarcomeric protein that resides within the heart muscle. Due to alternative splicing of TTN, the heart expresses two major isoforms (N2B and N2BA) that incorporate four distinct regions termed the Z-line, I-band, A-band, and M-line. Next-generation sequencing allows a large number of genes to be sequenced simultaneously and provides the opportunity to easily analyze giant genes such as TTN. Mutations in the TTN gene can cause cardiomyopathies, in particular dilated cardiomyopathy (DCM). DCM is the most common form of cardiomyopathy, and it is characterized by systolic dysfunction and dilation of the left ventricle. TTN truncating variants have been described as the most common cause of DCM, while the real impact of TTN missense variants in the pathogenesis of DCM is still unclear. In a recent population screening study, rare missense variants potentially pathogenic based on bioinformatic filtering represented only 12.6% of the several hundred rare TTN missense variants found, suggesting that missense variants are very common in TTN and are frequently benign. The aim of this review is to understand the clinical role of TTN mutations in DCM and in other cardiomyopathies. Whereas TTN truncations are common in DCM, there is evidence that TTN truncations are rare in the hypertrophic cardiomyopathy (HCM) phenotype. Furthermore, TTN mutations can also cause arrhythmogenic right ventricular cardiomyopathy (ARVC) with distinct clinical features and outcomes. Finally, the identification of a rare TTN missense variant cosegregating with the restrictive cardiomyopathy (RCM) phenotype suggests that TTN is a novel disease-causing gene in this disease. Clinical diagnostic testing is currently able to analyze over 100 cardiomyopathy genes, including TTN; however, the size and presence of extensive genetic variation in TTN presents clinical challenges in determining significant disease-causing mutations. This review discusses the current knowledge of TTN genetic variations in cardiomyopathies and the impact of the diagnosis of TTN pathogenic mutations in the clinical setting.
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Affiliation(s)
- Marta Gigli
- Adult Medical Genetics Program, Cardiovascular Institute, University of Colorado Denver, Aurora, CO, USA; Department of Cardiology, Hospital and University of Trieste, Trieste, Italy
| | - Rene L Begay
- Adult Medical Genetics Program, Cardiovascular Institute, University of Colorado Denver , Aurora, CO , USA
| | - Gaetano Morea
- Adult Medical Genetics Program, Cardiovascular Institute, University of Colorado Denver, Aurora, CO, USA; Department of Cardiology, Hospital and University of Trieste, Trieste, Italy
| | - Sharon L Graw
- Adult Medical Genetics Program, Cardiovascular Institute, University of Colorado Denver , Aurora, CO , USA
| | - Gianfranco Sinagra
- Department of Cardiology, Hospital and University of Trieste , Trieste , Italy
| | - Matthew R G Taylor
- Adult Medical Genetics Program, Cardiovascular Institute, University of Colorado Denver , Aurora, CO , USA
| | - Henk Granzier
- Molecular Cardiovascular Research Program, University of Arizona , Tucson, AZ , USA
| | - Luisa Mestroni
- Adult Medical Genetics Program, Cardiovascular Institute, University of Colorado Denver , Aurora, CO , USA
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134
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Lodka D, Pahuja A, Geers-Knörr C, Scheibe RJ, Nowak M, Hamati J, Köhncke C, Purfürst B, Kanashova T, Schmidt S, Glass DJ, Morano I, Heuser A, Kraft T, Bassel-Duby R, Olson EN, Dittmar G, Sommer T, Fielitz J. Muscle RING-finger 2 and 3 maintain striated-muscle structure and function. J Cachexia Sarcopenia Muscle 2016; 7:165-80. [PMID: 27493870 PMCID: PMC4863828 DOI: 10.1002/jcsm.12057] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Revised: 05/24/2015] [Accepted: 06/04/2015] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND The Muscle-specific RING-finger (MuRF) protein family of E3 ubiquitin ligases is important for maintenance of muscular structure and function. MuRF proteins mediate adaptation of striated muscles to stress. MuRF2 and MuRF3 bind to microtubules and are implicated in sarcomere formation with noticeable functional redundancy. However, if this redundancy is important for muscle function in vivo is unknown. Our objective was to investigate cooperative function of MuRF2 and MuRF3 in the skeletal muscle and the heart in vivo. METHODS MuRF2 and MuRF3 double knockout mice (DKO) were generated and phenotypically characterized. Skeletal muscle and the heart were investigated by morphological measurements, histological analyses, electron microscopy, immunoblotting, and real-time PCR. Isolated muscles were subjected to in vitro force measurements. Cardiac function was determined by echocardiography and working heart preparations. Function of cardiomyocytes was measured in vitro. Cell culture experiments and mass-spectrometry were used for mechanistic analyses. RESULTS DKO mice showed a protein aggregate myopathy in skeletal muscle. Maximal force development was reduced in DKO soleus and extensor digitorum longus. Additionally, a fibre type shift towards slow/type I fibres occurred in DKO soleus and extensor digitorum longus. MuRF2 and MuRF3-deficient hearts showed decreased systolic and diastolic function. Further analyses revealed an increased expression of the myosin heavy chain isoform beta/slow and disturbed calcium handling as potential causes for the phenotype in DKO hearts. CONCLUSIONS The redundant function of MuRF2 and MuRF3 is important for maintenance of skeletal muscle and cardiac structure and function in vivo.
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Affiliation(s)
- Dörte Lodka
- Department of Molecular Cardiology, Experimental and Clinical Research Center (ECRC) Max Delbrück Center for Molecular Medicine and Charité Universitätsmedizin Berlin, Campus Buch 13125 Berlin Germany
| | - Aanchal Pahuja
- Institute of Molecular and Cell Physiology Hannover Medical School 30625 Hannover Germany
| | - Cornelia Geers-Knörr
- Institute of Molecular and Cell Physiology Hannover Medical School 30625 Hannover Germany
| | - Renate J Scheibe
- Institute of Physiological Chemistry Hannover Medical School 30625 Hannover Germany
| | - Marcel Nowak
- Department of Molecular Cardiology, Experimental and Clinical Research Center (ECRC) Max Delbrück Center for Molecular Medicine and Charité Universitätsmedizin Berlin, Campus Buch 13125 Berlin Germany; Department of Intracellular Proteolysis Max Delbrück Center for Molecular Medicine 13125 Berlin Germany
| | - Jida Hamati
- Department of Molecular Cardiology, Experimental and Clinical Research Center (ECRC) Max Delbrück Center for Molecular Medicine and Charité Universitätsmedizin Berlin, Campus Buch 13125 Berlin Germany
| | - Clemens Köhncke
- Department of Molecular Muscle Physiology Max Delbrück Center for Molecular Medicine 13125 Berlin Germany
| | - Bettina Purfürst
- Department of Electron Microscopy Max Delbrück Center for Molecular Medicine 13125 Berlin Germany
| | - Tamara Kanashova
- Department of Mass Spectrometry Max Delbrück Center for Molecular Medicine 13125 Berlin Germany
| | - Sibylle Schmidt
- Department of Molecular Cardiology, Experimental and Clinical Research Center (ECRC) Max Delbrück Center for Molecular Medicine and Charité Universitätsmedizin Berlin, Campus Buch 13125 Berlin Germany
| | - David J Glass
- Novartis Institutes for Biomedical Research Cambridge Massachusetts 02139 USA
| | - Ingo Morano
- Department of Molecular Muscle Physiology Max Delbrück Center for Molecular Medicine 13125 Berlin Germany
| | - Arnd Heuser
- Department of Cardiovascular Molecular Genetics Max Delbrück Center for Molecular Medicine 13125 Berlin Germany
| | - Theresia Kraft
- Institute of Molecular and Cell Physiology Hannover Medical School 30625 Hannover Germany
| | - Rhonda Bassel-Duby
- Department of Molecular Biology University of Texas Southwestern Medical Center Dallas Texas 75390-9148 USA
| | - Eric N Olson
- Department of Molecular Biology University of Texas Southwestern Medical Center Dallas Texas 75390-9148 USA
| | - Gunnar Dittmar
- Department of Mass Spectrometry Max Delbrück Center for Molecular Medicine 13125 Berlin Germany
| | - Thomas Sommer
- Department of Intracellular Proteolysis Max Delbrück Center for Molecular Medicine 13125 Berlin Germany
| | - Jens Fielitz
- Department of Molecular Cardiology, Experimental and Clinical Research Center (ECRC) Max Delbrück Center for Molecular Medicine and Charité Universitätsmedizin Berlin, Campus Buch 13125 Berlin Germany; Department of Cardiology Charité Universitätsmedizin Berlin, Campus Virchow 13353 Berlin Germany
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135
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Sakuma K, Kinoshita M, Ito Y, Aizawa M, Aoi W, Yamaguchi A. p62/SQSTM1 but not LC3 is accumulated in sarcopenic muscle of mice. J Cachexia Sarcopenia Muscle 2016; 7:204-12. [PMID: 27493873 PMCID: PMC4864138 DOI: 10.1002/jcsm.12045] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Revised: 03/30/2015] [Accepted: 04/23/2015] [Indexed: 01/17/2023] Open
Abstract
AIM We investigated the pathway of autophagy signaling linked to sarcopenia of mice. METHODS Young adult (3-month) and aged (24- month) C57BL/6J mice were used. Using real-time PCR, Western blotting, and immunohistochemical microscopy, we evaluated the amounts of p62/SQSTM1, LC3, and Beclin-1 in the quadriceps muscle change with aging in mice. RESULTS Marked fiber atrophy (30%) and many fibers with central nuclei were observed in the aged mice. Western blotting using homogenate of the cytosolic fraction clearly showed that the amounts of p62/SQSTM1 and Beclin-1 proteins were significantly increased in the aged skeletal muscle. The amounts of these proteins in both nuclear and membrane fractions did not change significantly with age. Immunofluorescence labeling indicated that aged mice more frequently possessed p62/SQSTM1-positive fibers in the cytosol in quadriceps muscle than young ones (aged: 14% vs. young: 1%). In aged muscle, p62/SQSTM1-positive fibers were significantly smaller than the surrounding p62/SQSTM1-negative fibers. Aging did not elicit significant changes in the mRNA levels of p62/SQSTM1 and Beclin-1, but decreased LC3 mRNA level. In aged muscle, the location of p62/SQSTM1 immunoreactivity was similar to that of Beclin-1 protein, but not LC3. CONCLUSION Sarcopenia in mice appears to include a marked defect of autophagy signaling.
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Affiliation(s)
- Kunihiro Sakuma
- Research Center for Physical Fitness, Sports and HealthToyohashi University of TechnologyToyohashi, 1‐1 Hibarigaoka, Tenpaku‐cho441‐8580Japan
| | - Masakazu Kinoshita
- Research Center for Physical Fitness, Sports and HealthToyohashi University of TechnologyToyohashi, 1‐1 Hibarigaoka, Tenpaku‐cho441‐8580Japan
| | - Yoshinori Ito
- Research Center for Physical Fitness, Sports and HealthToyohashi University of TechnologyToyohashi, 1‐1 Hibarigaoka, Tenpaku‐cho441‐8580Japan
| | - Miki Aizawa
- Research Center for Physical Fitness, Sports and HealthToyohashi University of TechnologyToyohashi, 1‐1 Hibarigaoka, Tenpaku‐cho441‐8580Japan
| | - Wataru Aoi
- Laboratory of Health Science, Graduate School of Life and Environmental SciencesKyoto Prefectural UniversityKyotoJapan
| | - Akihiko Yamaguchi
- Department of Physical TherapyHealth Sciences University of HokkaidoKanazawaIshikari‐Tobetsu, HokkaidoJapan
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136
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Krüger M, Kötter S. Titin, a Central Mediator for Hypertrophic Signaling, Exercise-Induced Mechanosignaling and Skeletal Muscle Remodeling. Front Physiol 2016; 7:76. [PMID: 26973541 PMCID: PMC4771757 DOI: 10.3389/fphys.2016.00076] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Accepted: 02/15/2016] [Indexed: 01/09/2023] Open
Abstract
Titin is a giant scaffold protein with multiple functions in striated muscle physiology. Due to the elastic I-band domains and the filament-like integration in the half-sarcomere titin is an important factor for sarcomere assembly and serves as an adaptable molecular spring that determines myofilament distensibility. Protein-interactions e.g., with muscle ankyrin repeat proteins or muscle LIM-protein link titin to hypertrophic signaling and via p62 and Muscle Ring Finger proteins to mechanisms that control protein quality control. This review summarizes our current knowledge on titin as a central node for exercise-induced mechanosignaling and remodeling and further highlights the pathophysiological implications.
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Affiliation(s)
- Martina Krüger
- Institute of Cardiovascular Physiology, Heinrich Heine University Düsseldorf Düsseldorf, Germany
| | - Sebastian Kötter
- Institute of Cardiovascular Physiology, Heinrich Heine University Düsseldorf Düsseldorf, Germany
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137
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An eccentric calpain, CAPN3/p94/calpain-3. Biochimie 2016; 122:169-87. [DOI: 10.1016/j.biochi.2015.09.010] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Accepted: 09/07/2015] [Indexed: 01/09/2023]
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138
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Kenific CM, Stehbens SJ, Goldsmith J, Leidal AM, Faure N, Ye J, Wittmann T, Debnath J. NBR1 enables autophagy-dependent focal adhesion turnover. J Cell Biol 2016; 212:577-90. [PMID: 26903539 PMCID: PMC4772495 DOI: 10.1083/jcb.201503075] [Citation(s) in RCA: 113] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Accepted: 01/19/2016] [Indexed: 12/21/2022] Open
Abstract
The selective autophagy cargo receptor NBR1 enhances the disassembly of cell-matrix focal adhesions during cell migration. Autophagy is a catabolic pathway involving the sequestration of cellular contents into a double-membrane vesicle, the autophagosome. Although recent studies have demonstrated that autophagy supports cell migration, the underlying mechanisms remain unknown. Using live-cell imaging, we uncover that autophagy promotes optimal migratory rate and facilitates the dynamic assembly and disassembly of cell-matrix focal adhesions (FAs), which is essential for efficient motility. Additionally, our studies reveal that autophagosomes associate with FAs primarily during disassembly, suggesting autophagy locally facilitates the destabilization of cell-matrix contact sites. Furthermore, we identify the selective autophagy cargo receptor neighbor of BRCA1 (NBR1) as a key mediator of autophagy-dependent FA remodeling. NBR1 depletion impairs FA turnover and decreases targeting of autophagosomes to FAs, whereas ectopic expression of autophagy-competent, but not autophagy-defective, NBR1 enhances FA disassembly and reduces FA lifetime during migration. Our findings provide mechanistic insight into how autophagy promotes migration by revealing a requirement for NBR1-mediated selective autophagy in enabling FA disassembly in motile cells.
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Affiliation(s)
- Candia M Kenific
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA 94143 Biomedical Sciences Graduate Program, University of California, San Francisco, San Francisco, CA 94143
| | - Samantha J Stehbens
- Department of Cell and Tissue Biology, University of California, San Francisco, San Francisco, CA 94143
| | - Juliet Goldsmith
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA 94143 Biomedical Sciences Graduate Program, University of California, San Francisco, San Francisco, CA 94143
| | - Andrew M Leidal
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA 94143
| | - Nathalie Faure
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA 94143
| | - Jordan Ye
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA 94143
| | - Torsten Wittmann
- Department of Cell and Tissue Biology, University of California, San Francisco, San Francisco, CA 94143
| | - Jayanta Debnath
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA 94143
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Fischer M, Rikeit P, Knaus P, Coirault C. YAP-Mediated Mechanotransduction in Skeletal Muscle. Front Physiol 2016; 7:41. [PMID: 26909043 PMCID: PMC4754448 DOI: 10.3389/fphys.2016.00041] [Citation(s) in RCA: 77] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Accepted: 01/29/2016] [Indexed: 12/14/2022] Open
Abstract
Skeletal muscle is not only translating chemical energy into mechanical work, it is also a highly adaptive and regenerative tissue whose architecture and functionality is determined by its mechanical and physical environment. Processing intra- and extracellular mechanical signaling cues contributes to the regulation of cell growth, survival, migration and differentiation. Yes-associated Protein (YAP), a transcriptional coactivator downstream of the Hippo pathway and its paralog, the transcriptional co-activator with PDZ-binding motif (TAZ), were recently found to play a key role in mechanotransduction in various tissues including skeletal muscle. Furthermore, YAP/TAZ modulate myogenesis and muscle regeneration and abnormal YAP activity has been reported in muscular dystrophy and rhabdomyosarcoma. Here, we summarize the current knowledge of mechanosensing and -signaling in striated muscle. We highlight the role of YAP signaling and discuss the different routes and hypotheses of its regulation in the context of mechanotransduction.
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Affiliation(s)
- Martina Fischer
- Institut National de la Santé et de la Recherche Médicale, Centre National de la Recherche Scientifique, Center for Research in Myology, Sorbonne Universités Université Pierre et Marie Curie University Paris 06Paris, France; Institute of Chemistry and Biochemistry, Freie Universität BerlinBerlin, Germany
| | - Paul Rikeit
- Institute of Chemistry and Biochemistry, Freie Universität BerlinBerlin, Germany; Berlin-Brandenburg School for Regenerative Therapies, Charité-Universitätsmedizin BerlinBerlin, Germany
| | - Petra Knaus
- Institute of Chemistry and Biochemistry, Freie Universität Berlin Berlin, Germany
| | - Catherine Coirault
- Institut National de la Santé et de la Recherche Médicale, Centre National de la Recherche Scientifique, Center for Research in Myology, Sorbonne Universités Université Pierre et Marie Curie University Paris 06 Paris, France
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140
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Kimura T, Mandell M, Deretic V. Precision autophagy directed by receptor regulators - emerging examples within the TRIM family. J Cell Sci 2016; 129:881-91. [PMID: 26906420 DOI: 10.1242/jcs.163758] [Citation(s) in RCA: 79] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Selective autophagy entails cooperation between target recognition and assembly of the autophagic apparatus. Target recognition is conducted by receptors that often recognize tags, such as ubiquitin and galectins, although examples of selective autophagy independent of these tags are emerging. It is less known how receptors cooperate with the upstream autophagic regulators, beyond the well-characterized association of receptors with Atg8 or its homologs, such as LC3B (encoded by MAP1LC3B), on autophagic membranes. The molecular details of the emerging role in autophagy of the family of proteins called TRIMs shed light on the coordination between cargo recognition and the assembly and activation of the principal autophagy regulators. In their autophagy roles, TRIMs act both as receptors and as platforms ('receptor regulators') for the assembly of the core autophagy regulators, such as ULK1 and Beclin 1 in their activated state. As autophagic receptors, TRIMs can directly recognize endogenous or exogenous targets, obviating a need for intermediary autophagic tags, such as ubiquitin and galectins. The receptor and regulatory features embodied within the same entity allow TRIMs to govern cargo degradation in a highly exact process termed 'precision autophagy'.
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Affiliation(s)
- Tomonori Kimura
- Department of Molecular Genetics and Microbiology, University of New Mexico Health Sciences Center, 915 Camino de Salud, NE, Albuquerque, NM 87131, USA
| | - Michael Mandell
- Department of Molecular Genetics and Microbiology, University of New Mexico Health Sciences Center, 915 Camino de Salud, NE, Albuquerque, NM 87131, USA
| | - Vojo Deretic
- Department of Molecular Genetics and Microbiology, University of New Mexico Health Sciences Center, 915 Camino de Salud, NE, Albuquerque, NM 87131, USA
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141
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Kalamgi RC, Larsson L. Mechanical Signaling in the Pathophysiology of Critical Illness Myopathy. Front Physiol 2016; 7:23. [PMID: 26869939 PMCID: PMC4740381 DOI: 10.3389/fphys.2016.00023] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Accepted: 01/18/2016] [Indexed: 12/14/2022] Open
Abstract
The complete loss of mechanical stimuli of skeletal muscles, i.e., the loss of external strain, related to weight bearing, and internal strain, related to the contraction of muscle cells, is uniquely observed in pharmacologically paralyzed or deeply sedated mechanically ventilated intensive care unit (ICU) patients. The preferential loss of myosin and myosin associated proteins in limb and trunk muscles is a significant characteristic of critical illness myopathy (CIM) which separates CIM from other types of acquired muscle weaknesses in ICU patients. Mechanical silencing is an important factor triggering CIM. Microgravity or ground based microgravity models form the basis of research on the effect of muscle unloading-reloading, but the mechanisms and effects may differ from the ICU conditions. In order to understand how mechanical tension regulates muscle mass, it is critical to know how muscles sense mechanical information and convert stimulus to intracellular biochemical actions and changes in gene expression, a process called cellular mechanotransduction. In adult skeletal muscles and muscle fibers, this process may differ, the same stimulus can cause divergent response and the same fiber type may undergo opposite changes in different muscles. Skeletal muscle contains multiple types of mechano-sensors and numerous structures that can be affected differently and hence respond differently in distinct muscles.
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Affiliation(s)
- Rebeca C Kalamgi
- Basic and Clinical Muscle Biology, Department of Physiology and Pharmacology, Karolinska Institutet Stockholm, Sweden
| | - Lars Larsson
- Basic and Clinical Muscle Biology, Department of Physiology and Pharmacology, Karolinska InstitutetStockholm, Sweden; Department of Clinical Neuroscience, Clinical Neurophysiology, Karolinska InstitutetStockholm, Sweden
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142
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Gramlich M, Pane LS, Zhou Q, Chen Z, Murgia M, Schötterl S, Goedel A, Metzger K, Brade T, Parrotta E, Schaller M, Gerull B, Thierfelder L, Aartsma-Rus A, Labeit S, Atherton JJ, McGaughran J, Harvey RP, Sinnecker D, Mann M, Laugwitz KL, Gawaz MP, Moretti A. Antisense-mediated exon skipping: a therapeutic strategy for titin-based dilated cardiomyopathy. EMBO Mol Med 2016; 7:562-76. [PMID: 25759365 PMCID: PMC4492817 DOI: 10.15252/emmm.201505047] [Citation(s) in RCA: 83] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Frameshift mutations in the TTN gene encoding titin are a major cause for inherited forms of dilated cardiomyopathy (DCM), a heart disease characterized by ventricular dilatation, systolic dysfunction, and progressive heart failure. To date, there are no specific treatment options for DCM patients but heart transplantation. Here, we show the beneficial potential of reframing titin transcripts by antisense oligonucleotide (AON)-mediated exon skipping in human and murine models of DCM carrying a previously identified autosomal-dominant frameshift mutation in titin exon 326. Correction of TTN reading frame in patient-specific cardiomyocytes derived from induced pluripotent stem cells rescued defective myofibril assembly and stability and normalized the sarcomeric protein expression. AON treatment in Ttn knock-in mice improved sarcomere formation and contractile performance in homozygous embryos and prevented the development of the DCM phenotype in heterozygous animals. These results demonstrate that disruption of the titin reading frame due to a truncating DCM mutation can be restored by exon skipping in both patient cardiomyocytes in vitro and mouse heart in vivo, indicating RNA-based strategies as a potential treatment option for DCM.
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Affiliation(s)
- Michael Gramlich
- Department of Cardiology and Cardiovascular Diseases, Eberhard Karls University, Tübingen, Germany Victor Chang Cardiac Research Institute, Darlinghurst, NSW, Australia
| | - Luna Simona Pane
- I. Medical Department - Cardiology, Klinikum rechts der Isar - Technische Universität München, Munich, Germany
| | - Qifeng Zhou
- Department of Cardiology and Cardiovascular Diseases, Eberhard Karls University, Tübingen, Germany
| | - Zhifen Chen
- I. Medical Department - Cardiology, Klinikum rechts der Isar - Technische Universität München, Munich, Germany
| | - Marta Murgia
- Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, Martinsried, Germany Department of Biomedical Sciences, University of Padova, Padua, Italy
| | - Sonja Schötterl
- Department of Cardiology and Cardiovascular Diseases, Eberhard Karls University, Tübingen, Germany
| | - Alexander Goedel
- I. Medical Department - Cardiology, Klinikum rechts der Isar - Technische Universität München, Munich, Germany
| | - Katja Metzger
- Department of Cardiology and Cardiovascular Diseases, Eberhard Karls University, Tübingen, Germany
| | - Thomas Brade
- I. Medical Department - Cardiology, Klinikum rechts der Isar - Technische Universität München, Munich, Germany
| | - Elvira Parrotta
- I. Medical Department - Cardiology, Klinikum rechts der Isar - Technische Universität München, Munich, Germany Department of Experimental and Clinical Medicine, University Magna Graecia of Catanzaro, Catanzaro, Italy
| | - Martin Schaller
- Department of Dermatology, Eberhard Karls University, Tübingen, Germany
| | - Brenda Gerull
- Libin Cardiovascular Institute of Alberta and University of Calgary, Calgary, AB, Canada
| | | | - Annemieke Aartsma-Rus
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Siegfried Labeit
- Institute for Integrative Pathophysiology, Universitätsmedizin Mannheim, Mannheim, Germany
| | - John J Atherton
- Department of Cardiology, Royal Brisbane and Women's Hospital and University of Queensland School of Medicine, Brisbane, Australia
| | - Julie McGaughran
- Genetic Health Queensland, Royal Brisbane and Women's Hospital, Brisbane, Qld, Australia
| | - Richard P Harvey
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW, Australia St Vincent's Clinical School, University of New South Wales, Kensington, NSW, Australia
| | - Daniel Sinnecker
- I. Medical Department - Cardiology, Klinikum rechts der Isar - Technische Universität München, Munich, Germany
| | - Matthias Mann
- Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Karl-Ludwig Laugwitz
- I. Medical Department - Cardiology, Klinikum rechts der Isar - Technische Universität München, Munich, Germany DZHK (German Centre for Cardiovascular Research) - partner site Munich Heart Alliance, Munich, Germany
| | - Meinrad Paul Gawaz
- Department of Cardiology and Cardiovascular Diseases, Eberhard Karls University, Tübingen, Germany
| | - Alessandra Moretti
- I. Medical Department - Cardiology, Klinikum rechts der Isar - Technische Universität München, Munich, Germany DZHK (German Centre for Cardiovascular Research) - partner site Munich Heart Alliance, Munich, Germany
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143
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Reduced expression of MyHC slow isoform in rat soleus during unloading is accompanied by alterations of endogenous inhibitors of calcineurin/NFAT signaling pathway. J Muscle Res Cell Motil 2015; 37:7-16. [PMID: 26589960 DOI: 10.1007/s10974-015-9428-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Accepted: 10/15/2015] [Indexed: 10/22/2022]
Abstract
Under muscle disuse conditions decrease of expression of MyHC of slow type, and sometimes of type IIa, as well as upregulation of expression of IIb and IId/x isoforms were observed. Through dephosphorylation and entry of NFAT molecules to the nucleus calcineurin/NFATc1 signaling pathway promotes upregulation of the slow MyHC expression. We supposed that downregulation of calcineurin pathway took place during unloading. The study was aimed to analyze the states of the myonuclear NFAT inhibitors calsarcin I (CSI) and calsarcin II (CSII) (also referred to as myozenin II and I) and GSK3β in rat soleus during hindlimb suspension (HS). Male Wistar rats were subjected to 3, 7 and 14 day of HS. We found that after 3 days of HS the content of CSII mRNA twofold increased in soleus as compared to the controls. This level was increased by more than fivefold (as compared to control) after 2 weeks of HS. The increase of CSII mRNA expression may be explained as the mechanism of stabilization of fast phenotype. We found that from the 3 day till 14 day of HS the content of MuRF-1 and MuRF-2 in the nuclear fraction fourfold to fivefold increased in HS soleus. We supposed that nuclear import of the MuRFs allows to promote CSII expression during unloading. We also observed the decline of the phosphorylated GSK3β content in the nuclear extract of the soleus tissue. Thus decline of slow MyHC expression characteristic for the unloading conditions is accompanied with the increased expression and activation of the factors known to prevent NFAT accumulation in the myonuclei.
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144
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Ehler E. Cardiac cytoarchitecture - why the "hardware" is important for heart function! BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2015; 1863:1857-63. [PMID: 26577135 PMCID: PMC5104690 DOI: 10.1016/j.bbamcr.2015.11.006] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Revised: 11/05/2015] [Accepted: 11/09/2015] [Indexed: 01/05/2023]
Abstract
Cells that constitute fully differentiated tissues are characterised by an architecture that makes them perfectly suited for the job they have to do. This is especially obvious for cardiomyocytes, which have an extremely regular shape and display a paracrystalline arrangement of their cytoplasmic components. This article will focus on the two major cytoskeletal multiprotein complexes that are found in cardiomyocytes, the myofibrils, which are responsible for contraction and the intercalated disc, which mediates mechanical and electrochemical contact between individual cardiomyocytes. Recent studies have revealed that these two sites are also crucial in sensing excessive mechanical strain. Signalling processes will be triggered that## lead to changes in gene expression and eventually lead to an altered cardiac cytoarchitecture in the diseased heart, which results in a compromised function. Thus, understanding these changes and the signals that lead to them is crucial to design treatment strategies that can attenuate these processes. This article is part of a Special Issue entitled: Cardiomyocyte Biology: Integration of Developmental and Environmental Cues in the Heart edited by Marcus Schaub and Hughes Abriel.
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Affiliation(s)
- Elisabeth Ehler
- BHF Centre of Research Excellence at King's College London, Cardiovascular Division and Randall Division of Cell and Molecular Biophysics, London, UK.
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145
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Gerull B. The Rapidly Evolving Role of Titin in Cardiac Physiology and Cardiomyopathy. Can J Cardiol 2015; 31:1351-9. [DOI: 10.1016/j.cjca.2015.08.016] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Revised: 08/03/2015] [Accepted: 08/19/2015] [Indexed: 12/30/2022] Open
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146
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Leite FS, Minozzo FC, Kalganov A, Cornachione AS, Cheng YS, Leu NA, Han X, Saripalli C, Yates JR, Granzier H, Kashina AS, Rassier DE. Reduced passive force in skeletal muscles lacking protein arginylation. Am J Physiol Cell Physiol 2015; 310:C127-35. [PMID: 26511365 DOI: 10.1152/ajpcell.00269.2015] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Accepted: 10/28/2015] [Indexed: 11/22/2022]
Abstract
Arginylation is a posttranslational modification that plays a global role in mammals. Mice lacking the enzyme arginyltransferase in skeletal muscles exhibit reduced contractile forces that have been linked to a reduction in myosin cross-bridge formation. The role of arginylation in passive skeletal myofibril forces has never been investigated. In this study, we used single sarcomere and myofibril measurements and observed that lack of arginylation leads to a pronounced reduction in passive forces in skeletal muscles. Mass spectrometry indicated that skeletal muscle titin, the protein primarily linked to passive force generation, is arginylated on five sites located within the A band, an important area for protein-protein interactions. We propose a mechanism for passive force regulation by arginylation through modulation of protein-protein binding between the titin molecule and the thick filament. Key points are as follows: 1) active and passive forces were decreased in myofibrils and single sarcomeres isolated from muscles lacking arginyl-tRNA-protein transferase (ATE1). 2) Mass spectrometry revealed five sites for arginylation within titin molecules. All sites are located within the A-band portion of titin, an important region for protein-protein interactions. 3) Our data suggest that arginylation of titin is required for proper passive force development in skeletal muscles.
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Affiliation(s)
- Felipe S Leite
- Department of Kinesiology and Physical Education, McGill University, Montreal, Quebec, Canada
| | - Fábio C Minozzo
- Department of Kinesiology and Physical Education, McGill University, Montreal, Quebec, Canada
| | - Albert Kalganov
- Department of Kinesiology and Physical Education, McGill University, Montreal, Quebec, Canada
| | - Anabelle S Cornachione
- Department of Kinesiology and Physical Education, McGill University, Montreal, Quebec, Canada
| | - Yu-Shu Cheng
- Department of Kinesiology and Physical Education, McGill University, Montreal, Quebec, Canada
| | - Nicolae A Leu
- Department of Animal Biology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Xuemei Han
- The Scripps Research Institute, Department of Chemical Physiology, La Jolla, California
| | - Chandra Saripalli
- Department of Cellular and Molecular Medicine, University of Arizona, Tucson, Arizona; and
| | - John R Yates
- The Scripps Research Institute, Department of Chemical Physiology, La Jolla, California
| | - Henk Granzier
- Department of Cellular and Molecular Medicine, University of Arizona, Tucson, Arizona; and
| | - Anna S Kashina
- Department of Animal Biology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Dilson E Rassier
- Department of Kinesiology and Physical Education, McGill University, Montreal, Quebec, Canada; Departments of Physics and Physiology, McGill University, Montreal, Quebec, Canada
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147
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Pressure Overload by Transverse Aortic Constriction Induces Maladaptive Hypertrophy in a Titin-Truncated Mouse Model. BIOMED RESEARCH INTERNATIONAL 2015; 2015:163564. [PMID: 26504781 PMCID: PMC4609346 DOI: 10.1155/2015/163564] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/27/2015] [Accepted: 08/16/2015] [Indexed: 11/17/2022]
Abstract
Mutations in the giant sarcomeric protein titin (TTN) are a major cause for inherited forms of dilated cardiomyopathy (DCM). We have previously developed a mouse model that imitates a TTN truncation mutation we found in a large pedigree with DCM. While heterozygous Ttn knock-in mice do not display signs of heart failure under sedentary conditions, they recapitulate the human phenotype when exposed to the pharmacological stressor angiotensin II or isoproterenol. In this study we investigated the effects of pressure overload by transverse aortic constriction (TAC) in heterozygous (Het) Ttn knock-in mice. Two weeks after TAC, Het mice developed marked impairment of left ventricular ejection fraction (p < 0.05), while wild-type (WT) TAC mice did not. Het mice also trended toward increased ventricular end diastolic pressure and volume compared to WT littermates. We found an increase in histologically diffuse cardiac fibrosis in Het compared to WT in TAC mice. This study shows that a pattern of DCM can be induced by TAC-mediated pressure overload in a TTN-truncated mouse model. This model enlarges our arsenal of cardiac disease models, adding a valuable tool to understand cardiac pathophysiological remodeling processes and to develop therapeutic approaches to combat heart failure.
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148
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Santori M, Blanco-Verea A, Gil R, Cortis J, Becker K, Schneider PM, Carracedo A, Brion M. Broad-based molecular autopsy: a potential tool to investigate the involvement of subtle cardiac conditions in sudden unexpected death in infancy and early childhood. Arch Dis Child 2015; 100:952-6. [PMID: 26272908 DOI: 10.1136/archdischild-2015-308200] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Accepted: 07/01/2015] [Indexed: 12/25/2022]
Abstract
OBJECTIVES Sudden unexplained death in children is a tragic and traumatic event, often worsened when the cause of death cannot be determined. This work aimed to investigate the presence of putative pathogenic genetic variants in a broad spectrum of cardiomyopathy, channelopathy and aortic disease associated genes that may have increased these children's vulnerability to sudden cardiac death. DESIGN We performed molecular autopsy of 41 cases of sudden unexplained death in infants and children through massive parallel sequencing of up to 86 sudden cardiac death-related genes. Multiple in silico analyses were conducted together with a thorough review of the literature in order to prioritise the putative pathogenic variants. RESULTS A total of 63 variants in 35 cases were validated. The largest proportion of these variants is located within cardiomyopathy genes although this would have been more expected of channelopathy gene variants. Subtle microscopic features of heart tissue may indicate the presence of an early onset cardiomyopathy as a predisposing condition to sudden unexpected death in some individuals. CONCLUSIONS Next-generation sequencing technologies reveal the existence of a wide spectrum of rare and novel genetic variants in sarcomere genes, compared with that of cardiac ion channels, in sudden unexplained death in infants and children. Our findings encourage further investigation of the role of early onset inherited cardiomyopathies and other diseases involving myocardial dysfunction in these deaths. Early detection of variants in these individuals could help to unmask subtle forms of disease within their relatives, who would eventually benefit from better counselling about their genetic history.
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Affiliation(s)
- Montserrat Santori
- Xenética de Enfermidades Cardiovasculares, Instituto de Investigación Sanitaria de Santiago, Red de Investigación Cardiovascular (RIC), Santiago De Compostela, Spain Grupo de Medicina Xenómica, University of Santiago de Compostela, Santiago de Compostela, Spain Fundación Pública Galega de Medicina Xenómica, SERGAS, Santiago de Compostela, Spain
| | - Alejandro Blanco-Verea
- Xenética de Enfermidades Cardiovasculares, Instituto de Investigación Sanitaria de Santiago, Red de Investigación Cardiovascular (RIC), Santiago De Compostela, Spain Grupo de Medicina Xenómica, University of Santiago de Compostela, Santiago de Compostela, Spain Fundación Pública Galega de Medicina Xenómica, SERGAS, Santiago de Compostela, Spain
| | - Rocio Gil
- Xenética de Enfermidades Cardiovasculares, Instituto de Investigación Sanitaria de Santiago, Red de Investigación Cardiovascular (RIC), Santiago De Compostela, Spain Grupo de Medicina Xenómica, University of Santiago de Compostela, Santiago de Compostela, Spain Fundación Pública Galega de Medicina Xenómica, SERGAS, Santiago de Compostela, Spain
| | - Judith Cortis
- Faculty of Medicine, Institute of Legal Medicine, University of Cologne, Cologne, Germany
| | - Katrin Becker
- Faculty of Medicine, Institute of Legal Medicine, University of Cologne, Cologne, Germany
| | - Peter M Schneider
- Faculty of Medicine, Institute of Legal Medicine, University of Cologne, Cologne, Germany
| | - Angel Carracedo
- Grupo de Medicina Xenómica, University of Santiago de Compostela, Santiago de Compostela, Spain Fundación Pública Galega de Medicina Xenómica, SERGAS, Santiago de Compostela, Spain Center of Excellence in Genomic Medicine Research, King Abdulaziz University Jeddah, Kingdom of Saudi Arabia
| | - Maria Brion
- Xenética de Enfermidades Cardiovasculares, Instituto de Investigación Sanitaria de Santiago, Red de Investigación Cardiovascular (RIC), Santiago De Compostela, Spain Grupo de Medicina Xenómica, University of Santiago de Compostela, Santiago de Compostela, Spain Fundación Pública Galega de Medicina Xenómica, SERGAS, Santiago de Compostela, Spain
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149
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Identification of a Novel Mutation in the Titin Gene in a Chinese Family with Limb-Girdle Muscular Dystrophy 2J. Mol Neurobiol 2015; 53:5097-102. [DOI: 10.1007/s12035-015-9439-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Accepted: 09/10/2015] [Indexed: 01/01/2023]
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150
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Katzemich A, West RJH, Fukuzawa A, Sweeney ST, Gautel M, Sparrow J, Bullard B. Binding partners of the kinase domains in Drosophila obscurin and their effect on the structure of the flight muscle. J Cell Sci 2015; 128:3386-97. [PMID: 26251439 DOI: 10.1242/jcs.170639] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Accepted: 07/27/2015] [Indexed: 01/15/2023] Open
Abstract
Drosophila obscurin (Unc-89) is a titin-like protein in the M-line of the muscle sarcomere. Obscurin has two kinase domains near the C-terminus, both of which are predicted to be inactive. We have identified proteins binding to the kinase domains. Kinase domain 1 bound Bällchen (Ball, an active kinase), and both kinase domains 1 and 2 bound MASK (a 400-kDa protein with ankyrin repeats). Ball was present in the Z-disc and M-line of the indirect flight muscle (IFM) and was diffusely distributed in the sarcomere. MASK was present in both the M-line and the Z-disc. Reducing expression of Ball or MASK by siRNA resulted in abnormalities in the IFM, including missing M-lines and multiple Z-discs. Obscurin was still present, suggesting that the kinase domains act as a scaffold binding Ball and MASK. Unlike obscurin in vertebrate skeletal muscle, Drosophila obscurin is necessary for the correct assembly of the IFM sarcomere. We show that Ball and MASK act downstream of obscurin, and both are needed for development of a well defined M-line and Z-disc. The proteins have not previously been identified in Drosophila muscle.
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Affiliation(s)
- Anja Katzemich
- Department of Biology, University of York, York YO10 5DD, UK
| | - Ryan J H West
- Department of Biology, University of York, York YO10 5DD, UK
| | - Atsushi Fukuzawa
- King's College BHF Centre, Cardiovascular Division, London SE1 1UL, UK
| | - Sean T Sweeney
- Department of Biology, University of York, York YO10 5DD, UK
| | - Mathias Gautel
- King's College BHF Centre, Cardiovascular Division, London SE1 1UL, UK
| | - John Sparrow
- Department of Biology, University of York, York YO10 5DD, UK
| | - Belinda Bullard
- Department of Biology, University of York, York YO10 5DD, UK
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