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Doh CY, Schmidt AV, Chinthalapudi K, Stelzer JE. Bringing into focus the central domains C3-C6 of myosin binding protein C. Front Physiol 2024; 15:1370539. [PMID: 38487262 PMCID: PMC10937550 DOI: 10.3389/fphys.2024.1370539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2024] [Accepted: 02/19/2024] [Indexed: 03/17/2024] Open
Abstract
Myosin binding protein C (MyBPC) is a multi-domain protein with each region having a distinct functional role in muscle contraction. The central domains of MyBPC have often been overlooked due to their unclear roles. However, recent research shows promise in understanding their potential structural and regulatory functions. Understanding the central region of MyBPC is important because it may have specialized function that can be used as drug targets or for disease-specific therapies. In this review, we provide a brief overview of the evolution of our understanding of the central domains of MyBPC in regard to its domain structures, arrangement and dynamics, interaction partners, hypothesized functions, disease-causing mutations, and post-translational modifications. We highlight key research studies that have helped advance our understanding of the central region. Lastly, we discuss gaps in our current understanding and potential avenues to further research and discovery.
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Affiliation(s)
- Chang Yoon Doh
- Department of Medicine, School of Medicine, Case Western Reserve University, Cleveland, OH, United States
- Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University, Cleveland, OH, United States
| | - Alexandra V. Schmidt
- Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University, Cleveland, OH, United States
| | - Krishna Chinthalapudi
- Department of Physiology and Cell Biology, Dorothy M. Davis Heart & Lung Research Institute, College of Medicine, The Ohio State University, Columbus, OH, United States
| | - Julian E. Stelzer
- Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University, Cleveland, OH, United States
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2
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Pearce A, Ponnam S, Holt MR, Randall T, Beckingham R, Kho AL, Kampourakis T, Ehler E. Missense mutations in the central domains of cardiac myosin binding protein-C and their potential contribution to hypertrophic cardiomyopathy. J Biol Chem 2024; 300:105511. [PMID: 38042491 PMCID: PMC10772716 DOI: 10.1016/j.jbc.2023.105511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 11/05/2023] [Accepted: 11/20/2023] [Indexed: 12/04/2023] Open
Abstract
Myosin binding protein-C (MyBP-C) is a multidomain protein that regulates muscle contraction. Mutations in MYBPC3, the gene encoding for the cardiac variant (henceforth called cMyBP-C), are amongst the most frequent causes of hypertrophic cardiomyopathy. Most mutations lead to a truncated version of cMyBP-C, which is most likely unstable. However, missense mutations have also been reported, which tend to cluster in the central domains of the cMyBP-C molecule. This suggests that these central domains are more than just a passive spacer between the better characterized N- and C-terminal domains. Here, we investigated the potential impact of four different missense mutations, E542Q, G596R, N755K, and R820Q, which are spread over the domains C3 to C6, on the function of MyBP-C on both the isolated protein level and in cardiomyocytes in vitro. Effect on domain stability, interaction with thin filaments, binding to myosin, and subcellular localization behavior were assessed. Our studies show that these missense mutations result in slightly different phenotypes at the molecular level, which are mutation specific. The expected functional readout of each mutation provides a valid explanation for why cMyBP-C fails to work as a brake in the regulation of muscle contraction, which eventually results in a hypertrophic cardiomyopathy phenotype. We conclude that missense mutations in cMyBP-C must be evaluated in context of their domain localization, their effect on interaction with thin filaments and myosin, and their effect on protein stability to explain how they lead to disease.
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Affiliation(s)
- Amy Pearce
- School of Cardiovascular and Metabolic Medicine and Sciences, King's College London, London, United Kingdom; British Heart Foundation Centre of Research Excellence, King's College London, London, United Kingdom
| | - Saraswathi Ponnam
- British Heart Foundation Centre of Research Excellence, King's College London, London, United Kingdom; Randall Centre for Cell and Molecular Biophysics (School of Basic and Biosciences), King's College London, London, United Kingdom
| | - Mark R Holt
- School of Cardiovascular and Metabolic Medicine and Sciences, King's College London, London, United Kingdom; British Heart Foundation Centre of Research Excellence, King's College London, London, United Kingdom
| | - Thomas Randall
- School of Cardiovascular and Metabolic Medicine and Sciences, King's College London, London, United Kingdom; British Heart Foundation Centre of Research Excellence, King's College London, London, United Kingdom
| | - Rylan Beckingham
- School of Cardiovascular and Metabolic Medicine and Sciences, King's College London, London, United Kingdom; British Heart Foundation Centre of Research Excellence, King's College London, London, United Kingdom
| | - Ay Lin Kho
- British Heart Foundation Centre of Research Excellence, King's College London, London, United Kingdom; Randall Centre for Cell and Molecular Biophysics (School of Basic and Biosciences), King's College London, London, United Kingdom
| | - Thomas Kampourakis
- British Heart Foundation Centre of Research Excellence, King's College London, London, United Kingdom; Randall Centre for Cell and Molecular Biophysics (School of Basic and Biosciences), King's College London, London, United Kingdom
| | - Elisabeth Ehler
- School of Cardiovascular and Metabolic Medicine and Sciences, King's College London, London, United Kingdom; British Heart Foundation Centre of Research Excellence, King's College London, London, United Kingdom; Randall Centre for Cell and Molecular Biophysics (School of Basic and Biosciences), King's College London, London, United Kingdom.
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3
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Doh CY, Kampourakis T, Campbell KS, Stelzer JE. Basic science methods for the characterization of variants of uncertain significance in hypertrophic cardiomyopathy. Front Cardiovasc Med 2023; 10:1238515. [PMID: 37600050 PMCID: PMC10432852 DOI: 10.3389/fcvm.2023.1238515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2023] [Accepted: 07/20/2023] [Indexed: 08/22/2023] Open
Abstract
With the advent of next-generation whole genome sequencing, many variants of uncertain significance (VUS) have been identified in individuals suffering from inheritable hypertrophic cardiomyopathy (HCM). Unfortunately, this classification of a genetic variant results in ambiguity in interpretation, risk stratification, and clinical practice. Here, we aim to review some basic science methods to gain a more accurate characterization of VUS in HCM. Currently, many genomic data-based computational methods have been developed and validated against each other to provide a robust set of resources for researchers. With the continual improvement in computing speed and accuracy, in silico molecular dynamic simulations can also be applied in mutational studies and provide valuable mechanistic insights. In addition, high throughput in vitro screening can provide more biologically meaningful insights into the structural and functional effects of VUS. Lastly, multi-level mathematical modeling can predict how the mutations could cause clinically significant organ-level dysfunction. We discuss emerging technologies that will aid in better VUS characterization and offer a possible basic science workflow for exploring the pathogenicity of VUS in HCM. Although the focus of this mini review was on HCM, these basic science methods can be applied to research in dilated cardiomyopathy (DCM), restrictive cardiomyopathy (RCM), arrhythmogenic cardiomyopathy (ACM), or other genetic cardiomyopathies.
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Affiliation(s)
- Chang Yoon Doh
- School of Medicine, Case Western Reserve University, Cleveland, OH, United States
| | - Thomas Kampourakis
- Randall Centre for Cell and Molecular Biophysics, and British Heart Foundation Centre of Research Excellence, King’s College London, London, United Kingdom
| | - Kenneth S. Campbell
- Division of Cardiovascular Medicine, University of Kentucky, Lexington, KY, United States
| | - Julian E. Stelzer
- Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University, Cleveland, OH, United States
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Tudurachi BS, Zăvoi A, Leonte A, Țăpoi L, Ureche C, Bîrgoan SG, Chiuariu T, Anghel L, Radu R, Sascău RA, Stătescu C. An Update on MYBPC3 Gene Mutation in Hypertrophic Cardiomyopathy. Int J Mol Sci 2023; 24:10510. [PMID: 37445689 PMCID: PMC10341819 DOI: 10.3390/ijms241310510] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 06/17/2023] [Accepted: 06/20/2023] [Indexed: 07/15/2023] Open
Abstract
Hypertrophic cardiomyopathy (HCM) is the most prevalent genetically inherited cardiomyopathy that follows an autosomal dominant inheritance pattern. The majority of HCM cases can be attributed to mutation of the MYBPC3 gene, which encodes cMyBP-C, a crucial structural protein of the cardiac muscle. The manifestation of HCM's morphological, histological, and clinical symptoms is subject to the complex interplay of various determinants, including genetic mutation and environmental factors. Approximately half of MYBPC3 mutations give rise to truncated protein products, while the remaining mutations cause insertion/deletion, frameshift, or missense mutations of single amino acids. In addition, the onset of HCM may be attributed to disturbances in the protein and transcript quality control systems, namely, the ubiquitin-proteasome system and nonsense-mediated RNA dysfunctions. The aforementioned genetic modifications, which appear to be associated with unfavorable lifelong outcomes and are largely influenced by the type of mutation, exhibit a unique array of clinical manifestations ranging from asymptomatic to arrhythmic syncope and even sudden cardiac death. Although the current understanding of the MYBPC3 mutation does not comprehensively explain the varied phenotypic manifestations witnessed in patients with HCM, patients with pathogenic MYBPC3 mutations can exhibit an array of clinical manifestations ranging from asymptomatic to advanced heart failure and sudden cardiac death, leading to a higher rate of adverse clinical outcomes. This review focuses on MYBPC3 mutation and its characteristics as a prognostic determinant for disease onset and related clinical consequences in HCM.
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Affiliation(s)
- Bogdan-Sorin Tudurachi
- Department of Internal Medicine, Faculty of Medicine, Grigore T. Popa University of Medicine and Pharmacy of Iasi, 16 University Street, 700115 Iasi, Romania; (B.-S.T.); (L.Ț.); (C.U.); (L.A.); (R.R.); (R.A.S.); (C.S.)
- Prof. Dr. George I.M. Georgescu Institute of Cardiovascular Diseases, Carol I Boulevard, No. 50, 700503 Iasi, Romania; (A.L.); (S.G.B.); (T.C.)
| | - Alexandra Zăvoi
- Prof. Dr. George I.M. Georgescu Institute of Cardiovascular Diseases, Carol I Boulevard, No. 50, 700503 Iasi, Romania; (A.L.); (S.G.B.); (T.C.)
| | - Andreea Leonte
- Prof. Dr. George I.M. Georgescu Institute of Cardiovascular Diseases, Carol I Boulevard, No. 50, 700503 Iasi, Romania; (A.L.); (S.G.B.); (T.C.)
| | - Laura Țăpoi
- Department of Internal Medicine, Faculty of Medicine, Grigore T. Popa University of Medicine and Pharmacy of Iasi, 16 University Street, 700115 Iasi, Romania; (B.-S.T.); (L.Ț.); (C.U.); (L.A.); (R.R.); (R.A.S.); (C.S.)
- Prof. Dr. George I.M. Georgescu Institute of Cardiovascular Diseases, Carol I Boulevard, No. 50, 700503 Iasi, Romania; (A.L.); (S.G.B.); (T.C.)
| | - Carina Ureche
- Department of Internal Medicine, Faculty of Medicine, Grigore T. Popa University of Medicine and Pharmacy of Iasi, 16 University Street, 700115 Iasi, Romania; (B.-S.T.); (L.Ț.); (C.U.); (L.A.); (R.R.); (R.A.S.); (C.S.)
- Prof. Dr. George I.M. Georgescu Institute of Cardiovascular Diseases, Carol I Boulevard, No. 50, 700503 Iasi, Romania; (A.L.); (S.G.B.); (T.C.)
| | - Silviu Gabriel Bîrgoan
- Prof. Dr. George I.M. Georgescu Institute of Cardiovascular Diseases, Carol I Boulevard, No. 50, 700503 Iasi, Romania; (A.L.); (S.G.B.); (T.C.)
| | - Traian Chiuariu
- Prof. Dr. George I.M. Georgescu Institute of Cardiovascular Diseases, Carol I Boulevard, No. 50, 700503 Iasi, Romania; (A.L.); (S.G.B.); (T.C.)
| | - Larisa Anghel
- Department of Internal Medicine, Faculty of Medicine, Grigore T. Popa University of Medicine and Pharmacy of Iasi, 16 University Street, 700115 Iasi, Romania; (B.-S.T.); (L.Ț.); (C.U.); (L.A.); (R.R.); (R.A.S.); (C.S.)
- Prof. Dr. George I.M. Georgescu Institute of Cardiovascular Diseases, Carol I Boulevard, No. 50, 700503 Iasi, Romania; (A.L.); (S.G.B.); (T.C.)
| | - Rodica Radu
- Department of Internal Medicine, Faculty of Medicine, Grigore T. Popa University of Medicine and Pharmacy of Iasi, 16 University Street, 700115 Iasi, Romania; (B.-S.T.); (L.Ț.); (C.U.); (L.A.); (R.R.); (R.A.S.); (C.S.)
- Prof. Dr. George I.M. Georgescu Institute of Cardiovascular Diseases, Carol I Boulevard, No. 50, 700503 Iasi, Romania; (A.L.); (S.G.B.); (T.C.)
| | - Radu Andy Sascău
- Department of Internal Medicine, Faculty of Medicine, Grigore T. Popa University of Medicine and Pharmacy of Iasi, 16 University Street, 700115 Iasi, Romania; (B.-S.T.); (L.Ț.); (C.U.); (L.A.); (R.R.); (R.A.S.); (C.S.)
- Prof. Dr. George I.M. Georgescu Institute of Cardiovascular Diseases, Carol I Boulevard, No. 50, 700503 Iasi, Romania; (A.L.); (S.G.B.); (T.C.)
| | - Cristian Stătescu
- Department of Internal Medicine, Faculty of Medicine, Grigore T. Popa University of Medicine and Pharmacy of Iasi, 16 University Street, 700115 Iasi, Romania; (B.-S.T.); (L.Ț.); (C.U.); (L.A.); (R.R.); (R.A.S.); (C.S.)
- Prof. Dr. George I.M. Georgescu Institute of Cardiovascular Diseases, Carol I Boulevard, No. 50, 700503 Iasi, Romania; (A.L.); (S.G.B.); (T.C.)
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De Lange WJ, Farrell ET, Hernandez JJ, Stempien A, Kreitzer CR, Jacobs DR, Petty DL, Moss RL, Crone WC, Ralphe JC. cMyBP-C ablation in human engineered cardiac tissue causes progressive Ca2+-handling abnormalities. J Gen Physiol 2023; 155:e202213204. [PMID: 36893011 PMCID: PMC10038829 DOI: 10.1085/jgp.202213204] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 01/02/2023] [Accepted: 02/14/2023] [Indexed: 03/10/2023] Open
Abstract
Truncation mutations in cardiac myosin binding protein C (cMyBP-C) are common causes of hypertrophic cardiomyopathy (HCM). Heterozygous carriers present with classical HCM, while homozygous carriers present with early onset HCM that rapidly progress to heart failure. We used CRISPR-Cas9 to introduce heterozygous (cMyBP-C+/-) and homozygous (cMyBP-C-/-) frame-shift mutations into MYBPC3 in human iPSCs. Cardiomyocytes derived from these isogenic lines were used to generate cardiac micropatterns and engineered cardiac tissue constructs (ECTs) that were characterized for contractile function, Ca2+-handling, and Ca2+-sensitivity. While heterozygous frame shifts did not alter cMyBP-C protein levels in 2-D cardiomyocytes, cMyBP-C+/- ECTs were haploinsufficient. cMyBP-C-/- cardiac micropatterns produced increased strain with normal Ca2+-handling. After 2 wk of culture in ECT, contractile function was similar between the three genotypes; however, Ca2+-release was slower in the setting of reduced or absent cMyBP-C. At 6 wk in ECT culture, the Ca2+-handling abnormalities became more pronounced in both cMyBP-C+/- and cMyBP-C-/- ECTs, and force production became severely depressed in cMyBP-C-/- ECTs. RNA-seq analysis revealed enrichment of differentially expressed hypertrophic, sarcomeric, Ca2+-handling, and metabolic genes in cMyBP-C+/- and cMyBP-C-/- ECTs. Our data suggest a progressive phenotype caused by cMyBP-C haploinsufficiency and ablation that initially is hypercontractile, but progresses to hypocontractility with impaired relaxation. The severity of the phenotype correlates with the amount of cMyBP-C present, with more severe earlier phenotypes observed in cMyBP-C-/- than cMyBP-C+/- ECTs. We propose that while the primary effect of cMyBP-C haploinsufficiency or ablation may relate to myosin crossbridge orientation, the observed contractile phenotype is Ca2+-mediated.
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Affiliation(s)
- Willem J. De Lange
- Departments of Pediatrics, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA
| | - Emily T. Farrell
- Departments of Pediatrics, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA
| | - Jonathan J. Hernandez
- Departments of Pediatrics, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA
| | - Alana Stempien
- Departments of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, USA
- Wisconsin Institute for Discovery, University of Wisconsin-Madison, Madison, WI, USA
| | - Caroline R. Kreitzer
- Departments of Pediatrics, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA
| | - Derek R. Jacobs
- Departments of Pediatrics, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA
| | - Dominique L. Petty
- Departments of Pediatrics, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA
| | - Richard L. Moss
- Cell and Regenerative Biology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA
| | - Wendy C. Crone
- Departments of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, USA
- Wisconsin Institute for Discovery, University of Wisconsin-Madison, Madison, WI, USA
- Engineering Physics, University of Wisconsin-Madison, Madison, WI, USA
- Materials Science and Engineering, University of Wisconsin-Madison, Madison, WI, USA
| | - J. Carter Ralphe
- Departments of Pediatrics, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA
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6
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Suay-Corredera C, Alegre-Cebollada J. The mechanics of the heart: zooming in on hypertrophic cardiomyopathy and cMyBP-C. FEBS Lett 2022; 596:703-746. [PMID: 35224729 DOI: 10.1002/1873-3468.14301] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 01/10/2022] [Accepted: 01/14/2022] [Indexed: 11/10/2022]
Abstract
Hypertrophic cardiomyopathy (HCM), a disease characterized by cardiac muscle hypertrophy and hypercontractility, is the most frequently inherited disorder of the heart. HCM is mainly caused by variants in genes encoding proteins of the sarcomere, the basic contractile unit of cardiomyocytes. The most frequently mutated among them is MYBPC3, which encodes cardiac myosin-binding protein C (cMyBP-C), a key regulator of sarcomere contraction. In this review, we summarize clinical and genetic aspects of HCM and provide updated information on the function of the healthy and HCM sarcomere, as well as on emerging therapeutic options targeting sarcomere mechanical activity. Building on what is known about cMyBP-C activity, we examine different pathogenicity drivers by which MYBPC3 variants can cause disease, focussing on protein haploinsufficiency as a common pathomechanism also in nontruncating variants. Finally, we discuss recent evidence correlating altered cMyBP-C mechanical properties with HCM development.
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Lu J, Li H, Zhang H, Lin Z, Xu C, Xu X, Hu L, Luan Z, Lou Y, Tang S. The distal arthrogryposis-linked p.R63C variant promotes the stability and nuclear accumulation of TNNT3. J Clin Lab Anal 2021; 35:e24089. [PMID: 34766372 PMCID: PMC8649346 DOI: 10.1002/jcla.24089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 09/13/2021] [Accepted: 10/09/2021] [Indexed: 11/11/2022] Open
Abstract
Background Distal arthrogryposis (DA) is comprised of a group of rare developmental disorders in muscle, characterized by multiple congenital contractures of the distal limbs. Fast skeletal muscle troponin‐T (TNNT3) protein is abundantly expressed in skeletal muscle and plays an important role in DA. Missense variants in TNNT3 are associated with DA, but few studies have fully clarified its pathogenic role. Methods Sanger sequencing was performed in three generation of a Chinese family with DA. To determine how the p.R63C variant contributed to DA, we identified a variant in TNNT3 (NM_006757.4): c.187C>T (p.R63C). And then we investigated the effects of the arginine to cysteine substitution on the distribution pattern and the half‐life of TNNT3 protein. Results The protein levels of TNNT3 in affected family members were 0.8‐fold higher than that without the disorder. TNNT3 protein could be degraded by the ubiquitin‐proteasome complex, and the p.R63C variant did not change TNNT3 nuclear localization, but significantly prolonged its half‐life from 2.5 to 7 h, to promote its accumulation in the nucleus. Conclusion The p.R63C variant increased the stability of TNNT3 and promoted nuclear accumulation, which suggested its role in DA.
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Affiliation(s)
- Jinfang Lu
- Wenzhou Key Laboratory of Sanitary Microbiology, Key Laboratory of Laboratory Medicine, Ministry of Education, China, School of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou, China
| | - Huanzheng Li
- Key Laboratory of Birth Defects, Department of Genetics, Wenzhou Central Hospital, Wenzhou, China
| | - He Zhang
- Zhejiang Provincial Key Laboratory for Subtropical Water Environment and Marine Biological Resources Protection, College of Life and Environmental Sciences, Wenzhou University, Wenzhou, China
| | - Zhengxiu Lin
- The Second Affiliated Hospital and Yuying Children's Hospital of WMU, School of the Second Clinical Medical Sciences, Wenzhou Medical University, Wenzhou, China
| | - Chenyang Xu
- Key Laboratory of Birth Defects, Department of Genetics, Wenzhou Central Hospital, Wenzhou, China
| | - Xueqin Xu
- Key Laboratory of Birth Defects, Department of Genetics, Wenzhou Central Hospital, Wenzhou, China
| | - Lin Hu
- Key Laboratory of Medical Genetic, School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, China
| | - Zhaotang Luan
- Key Laboratory of Medical Genetic, School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, China
| | - Yongliang Lou
- Wenzhou Key Laboratory of Sanitary Microbiology, Key Laboratory of Laboratory Medicine, Ministry of Education, China, School of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou, China
| | - Shaohua Tang
- Key Laboratory of Birth Defects, Department of Genetics, Wenzhou Central Hospital, Wenzhou, China.,Key Laboratory of Medical Genetic, School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, China
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Schwäbe FV, Peter EK, Taft MH, Manstein DJ. Assessment of the Contribution of a Thermodynamic and Mechanical Destabilization of Myosin-Binding Protein C Domain C2 to the Pathomechanism of Hypertrophic Cardiomyopathy-Causing Double Mutation MYBPC3Δ25bp/D389V. Int J Mol Sci 2021; 22:ijms222111949. [PMID: 34769381 PMCID: PMC8584774 DOI: 10.3390/ijms222111949] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 10/31/2021] [Accepted: 11/02/2021] [Indexed: 01/01/2023] Open
Abstract
Mutations in the gene encoding cardiac myosin-binding protein-C (MyBPC), a thick filament assembly protein that stabilizes sarcomeric structure and regulates cardiac function, are a common cause for the development of hypertrophic cardiomyopathy. About 10% of carriers of the Δ25bp variant of MYBPC3, which is common in individuals from South Asia, are also carriers of the D389V variant on the same allele. Compared with noncarriers and those with MYBPC3Δ25bp alone, indicators for the development of hypertrophic cardiomyopathy occur with increased frequency in MYBPC3Δ25bp/D389V carriers. Residue D389 lies in the IgI-like C2 domain that is part of the N-terminal region of MyBPC. To probe the effects of mutation D389V on structure, thermostability, and protein–protein interactions, we produced and characterized wild-type and mutant constructs corresponding to the isolated 10 kDa C2 domain and a 52 kDa N-terminal fragment that includes subdomains C0 to C2. Our results show marked reductions in the melting temperatures of D389V mutant constructs. Interactions of construct C0–C2 D389V with the cardiac isoforms of myosin-2 and actin remain unchanged. Molecular dynamics simulations reveal changes in the stiffness and conformer dynamics of domain C2 caused by mutation D389V. Our results suggest a pathomechanism for the development of HCM based on the toxic buildup of misfolded protein in young MYBPC3Δ25bp/D389V carriers that is supplanted and enhanced by C-zone haploinsufficiency at older ages.
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Affiliation(s)
- Frederic V. Schwäbe
- Fritz Hartmann Centre for Medical Research, Institute for Biophysical Chemistry, Hannover Medical School, Carl Neuberg Str. 1, D-30625 Hannover, Germany; (F.V.S.); (E.K.P.); (M.H.T.)
| | - Emanuel K. Peter
- Fritz Hartmann Centre for Medical Research, Institute for Biophysical Chemistry, Hannover Medical School, Carl Neuberg Str. 1, D-30625 Hannover, Germany; (F.V.S.); (E.K.P.); (M.H.T.)
| | - Manuel H. Taft
- Fritz Hartmann Centre for Medical Research, Institute for Biophysical Chemistry, Hannover Medical School, Carl Neuberg Str. 1, D-30625 Hannover, Germany; (F.V.S.); (E.K.P.); (M.H.T.)
| | - Dietmar J. Manstein
- Fritz Hartmann Centre for Medical Research, Institute for Biophysical Chemistry, Hannover Medical School, Carl Neuberg Str. 1, D-30625 Hannover, Germany; (F.V.S.); (E.K.P.); (M.H.T.)
- Division for Structural Biochemistry, Hannover Medical School, Carl Neuberg Str. 1, D-30625 Hannover, Germany
- Correspondence:
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9
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Suay-Corredera C, Pricolo MR, Herrero-Galán E, Velázquez-Carreras D, Sánchez-Ortiz D, García-Giustiniani D, Delgado J, Galano-Frutos JJ, García-Cebollada H, Vilches S, Domínguez F, Molina MS, Barriales-Villa R, Frisso G, Sancho J, Serrano L, García-Pavía P, Monserrat L, Alegre-Cebollada J. Protein haploinsufficiency drivers identify MYBPC3 variants that cause hypertrophic cardiomyopathy. J Biol Chem 2021; 297:100854. [PMID: 34097875 PMCID: PMC8260873 DOI: 10.1016/j.jbc.2021.100854] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 05/21/2021] [Accepted: 06/03/2021] [Indexed: 02/06/2023] Open
Abstract
Hypertrophic cardiomyopathy (HCM) is the most common inherited cardiac disease. Variants in MYBPC3, the gene encoding cardiac myosin-binding protein C (cMyBP-C), are the leading cause of HCM. However, the pathogenicity status of hundreds of MYBPC3 variants found in patients remains unknown, as a consequence of our incomplete understanding of the pathomechanisms triggered by HCM-causing variants. Here, we examined 44 nontruncating MYBPC3 variants that we classified as HCM-linked or nonpathogenic according to cosegregation and population genetics criteria. We found that around half of the HCM-linked variants showed alterations in RNA splicing or protein stability, both of which can lead to cMyBP-C haploinsufficiency. These protein haploinsufficiency drivers associated with HCM pathogenicity with 100% and 94% specificity, respectively. Furthermore, we uncovered that 11% of nontruncating MYBPC3 variants currently classified as of uncertain significance in ClinVar induced one of these molecular phenotypes. Our strategy, which can be applied to other conditions induced by protein loss of function, supports the idea that cMyBP-C haploinsufficiency is a fundamental pathomechanism in HCM.
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Affiliation(s)
| | - Maria Rosaria Pricolo
- Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain; Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università di Napoli Federico II, Naples, Italy
| | | | | | | | | | - Javier Delgado
- EMBL/CRG Systems Biology Research Unit, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Juan José Galano-Frutos
- Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, Universidad de Zaragoza, Zaragoza, Spain; Biocomputation and Complex Systems Physics Institute (BIFI). Joint Units BIFI-IQFR (CSIC) and GBs-CSIC, Universidad de Zaragoza, Zaragoza, Spain
| | - Helena García-Cebollada
- Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, Universidad de Zaragoza, Zaragoza, Spain; Biocomputation and Complex Systems Physics Institute (BIFI). Joint Units BIFI-IQFR (CSIC) and GBs-CSIC, Universidad de Zaragoza, Zaragoza, Spain
| | - Silvia Vilches
- Heart Failure and Inherited Cardiac Diseases Unit. Department of Cardiology. Hospital Universitario Puerta de Hierro, Madrid, Spain; European Reference Network for Rare and Low Prevalence Complex Diseases of the Heart (ERN GUARD-HEART), Madrid, Spain
| | - Fernando Domínguez
- Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain; Heart Failure and Inherited Cardiac Diseases Unit. Department of Cardiology. Hospital Universitario Puerta de Hierro, Madrid, Spain; European Reference Network for Rare and Low Prevalence Complex Diseases of the Heart (ERN GUARD-HEART), Madrid, Spain; Centro de Investigación Biomédica en Red en Enfermedades Cardiovasculares (CIBERCV), Madrid, Spain
| | - María Sabater Molina
- European Reference Network for Rare and Low Prevalence Complex Diseases of the Heart (ERN GUARD-HEART), Madrid, Spain; Hospital C. Universitario Virgen de la Arrixaca, El Palmar, Murcia, Spain
| | - Roberto Barriales-Villa
- Centro de Investigación Biomédica en Red en Enfermedades Cardiovasculares (CIBERCV), Madrid, Spain; Unidad de Cardiopatías Familiares, Instituto de Investigación Biomédica de A Coruña (INIBIC), Complexo Hospitalario Universitario de A Coruña, Servizo Galego de Saúde (SERGAS), Universidade da Coruña, A Coruña, Spain
| | - Giulia Frisso
- Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università di Napoli Federico II, Naples, Italy; CEINGE Biotecnologie Avanzate, scarl, Naples, Italy
| | - Javier Sancho
- Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, Universidad de Zaragoza, Zaragoza, Spain; Biocomputation and Complex Systems Physics Institute (BIFI). Joint Units BIFI-IQFR (CSIC) and GBs-CSIC, Universidad de Zaragoza, Zaragoza, Spain; Aragon Health Research Institute (IIS Aragón), Zaragoza, Spain
| | - Luis Serrano
- EMBL/CRG Systems Biology Research Unit, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain; Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain; Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Pablo García-Pavía
- Heart Failure and Inherited Cardiac Diseases Unit. Department of Cardiology. Hospital Universitario Puerta de Hierro, Madrid, Spain; European Reference Network for Rare and Low Prevalence Complex Diseases of the Heart (ERN GUARD-HEART), Madrid, Spain; Centro de Investigación Biomédica en Red en Enfermedades Cardiovasculares (CIBERCV), Madrid, Spain; Universidad Francisco de Vitoria (UFV), Pozuelo de Alarcón, Madrid, Spain
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10
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Suay-Corredera C, Pricolo MR, Velázquez-Carreras D, Pathak D, Nandwani N, Pimenta-Lopes C, Sánchez-Ortiz D, Urrutia-Irazabal I, Vilches S, Dominguez F, Frisso G, Monserrat L, García-Pavía P, de Sancho D, Spudich JA, Ruppel KM, Herrero-Galán E, Alegre-Cebollada J. Nanomechanical Phenotypes in Cardiac Myosin-Binding Protein C Mutants That Cause Hypertrophic Cardiomyopathy. ACS NANO 2021; 15:10203-10216. [PMID: 34060810 PMCID: PMC8514129 DOI: 10.1021/acsnano.1c02242] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Hypertrophic cardiomyopathy (HCM) is a disease of the myocardium caused by mutations in sarcomeric proteins with mechanical roles, such as the molecular motor myosin. Around half of the HCM-causing genetic variants target contraction modulator cardiac myosin-binding protein C (cMyBP-C), although the underlying pathogenic mechanisms remain unclear since many of these mutations cause no alterations in protein structure and stability. As an alternative pathomechanism, here we have examined whether pathogenic mutations perturb the nanomechanics of cMyBP-C, which would compromise its modulatory mechanical tethers across sliding actomyosin filaments. Using single-molecule atomic force spectroscopy, we have quantified mechanical folding and unfolding transitions in cMyBP-C domains targeted by HCM mutations that do not induce RNA splicing alterations or protein thermodynamic destabilization. Our results show that domains containing mutation R495W are mechanically weaker than wild-type at forces below 40 pN and that R502Q mutant domains fold faster than wild-type. None of these alterations are found in control, nonpathogenic variants, suggesting that nanomechanical phenotypes induced by pathogenic cMyBP-C mutations contribute to HCM development. We propose that mutation-induced nanomechanical alterations may be common in mechanical proteins involved in human pathologies.
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Affiliation(s)
| | - Maria Rosaria Pricolo
- Centro Nacional de Investigaciones Cardiovasculares (CNIC), 28029, Madrid, Spain
- Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università di Napoli Federico II, 80131, Naples, Italy
| | | | - Divya Pathak
- Department of Biochemistry, Stanford University School of Medicine, Stanford, California 94305, United States
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, California 94305, United States
| | - Neha Nandwani
- Department of Biochemistry, Stanford University School of Medicine, Stanford, California 94305, United States
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, California 94305, United States
| | | | - David Sánchez-Ortiz
- Centro Nacional de Investigaciones Cardiovasculares (CNIC), 28029, Madrid, Spain
| | | | - Silvia Vilches
- Heart Failure and Inherited Cardiac Diseases Unit, Department of Cardiology, Hospital Universitario Puerta de Hierro, 28222, Madrid, Spain
- European Reference Network for Rare and Low Prevalence Complex Diseases of the Heart (ERN GUARD-HEART, http://guardheart.ern-net.eu/), 28222, Madrid, Spain
| | - Fernando Dominguez
- Centro Nacional de Investigaciones Cardiovasculares (CNIC), 28029, Madrid, Spain
- Heart Failure and Inherited Cardiac Diseases Unit, Department of Cardiology, Hospital Universitario Puerta de Hierro, 28222, Madrid, Spain
- European Reference Network for Rare and Low Prevalence Complex Diseases of the Heart (ERN GUARD-HEART, http://guardheart.ern-net.eu/), 28222, Madrid, Spain
- Centro de Investigación Biomédica en Red en Enfermedades Cardiovasculares (CIBERCV), 28029, Madrid, Spain
| | - Giulia Frisso
- Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università di Napoli Federico II, 80131, Naples, Italy
- CEINGE Biotecnologie Avanzate, scarl, 80145, Naples, Italy
| | | | - Pablo García-Pavía
- Heart Failure and Inherited Cardiac Diseases Unit, Department of Cardiology, Hospital Universitario Puerta de Hierro, 28222, Madrid, Spain
- European Reference Network for Rare and Low Prevalence Complex Diseases of the Heart (ERN GUARD-HEART, http://guardheart.ern-net.eu/), 28222, Madrid, Spain
- Centro de Investigación Biomédica en Red en Enfermedades Cardiovasculares (CIBERCV), 28029, Madrid, Spain
- Universidad Francisco de Vitoria (UFV), 28223, Pozuelo de Alarcón, Madrid, Spain
| | - David de Sancho
- Polimero eta Material Aurreratuak: Fisika, Kimika eta Teknologia, Kimika Fakultatea, Euskal Herriko Unibertsitatea UPV/EHU, 20018, Donostia-San Sebastián, Spain
- Donostia International Physics Center (DIPC), 20018, Donostia-San Sebastián, Spain
| | - James A Spudich
- Department of Biochemistry, Stanford University School of Medicine, Stanford, California 94305, United States
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, California 94305, United States
| | - Kathleen M Ruppel
- Department of Biochemistry, Stanford University School of Medicine, Stanford, California 94305, United States
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, California 94305, United States
| | - Elías Herrero-Galán
- Centro Nacional de Investigaciones Cardiovasculares (CNIC), 28029, Madrid, Spain
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11
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de Lange WJ, Farrell ET, Kreitzer CR, Jacobs DR, Lang D, Glukhov AV, Ralphe JC. Human iPSC-engineered cardiac tissue platform faithfully models important cardiac physiology. Am J Physiol Heart Circ Physiol 2021; 320:H1670-H1686. [PMID: 33606581 DOI: 10.1152/ajpheart.00941.2020] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Cardiomyocytes derived from human induced pluripotent stem cells (hiPSC-CM) may provide an important bridge between animal models and the intact human myocardium. Fulfilling this potential is hampered by their relative immaturity, leading to poor physiological responsiveness. hiPSC-CMs grown in traditional two-dimensional (2D) culture lack a t-tubular system, have only rudimentary intracellular calcium-handling systems, express predominantly embryonic sarcomeric protein isoforms, and preferentially use glucose as an energy substrate. Culturing hiPSC-CM in a variety of three-dimensional (3D) environments and the addition of nutritional, pharmacological, and electromechanical stimuli have proven, to various degrees, to be beneficial for maturation. We present a detailed assessment of a novel model in which hiPSC-CMs and hiPSC-derived cardiac fibroblasts are cocultured in a 3D fibrin matrix to form engineered cardiac tissue constructs (hiPSC-ECTs). The hiPSC-ECTs are responsive to physiological stimuli, including stretch, frequency, and β-adrenergic stimulation, develop a t-tubular system, and demonstrate calcium-handling and contractile kinetics that compare favorably with ventricular human myocardium. Furthermore, transcript levels of various genes involved in calcium-handling and contraction are increased. These markers of maturation become more robust over a relatively short period of time in culture (6 wk vs. 2 wk in hiPSC-ECTs). A comparison of the hiPSC-ECT molecular and performance variables with those of human cardiac tissue and other available engineered tissue platforms is provided to aid selection of the most appropriate platform for the research question at hand. Important and noteworthy aspects of this human cardiac model system are its reliance on "off-the-shelf" equipment, ability to provide detailed physiological performance data, and the ability to achieve a relatively mature cardiac physiology without additional nutritional, pharmacological, and electromechanical stimuli that may elicit unintended effects on function.NEW & NOTEWORTHY This study seeks to provide an in-depth assessment of contractile performance of human iPSC-derived cardiomyocytes cultured together with fibroblasts in a 3-dimensional-engineered tissue and compares performance both over time as cells mature, and with corresponding measures found in the literature using alternative 3D culture configurations. The suitability of 3D-engineered human cardiac tissues to model cardiac function is emphasized, and data provided to assist in the selection of the most appropriate configuration based on the target application.
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Affiliation(s)
- Willem J de Lange
- Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
| | - Emily T Farrell
- Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
| | - Caroline R Kreitzer
- Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
| | - Derek R Jacobs
- Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
| | - Di Lang
- Department of Medicine Cardiovascular Medicine, University of Wisconsin-Madison School of Medicine and Public Health, Madison, Wisconsin
| | - Alexey V Glukhov
- Department of Medicine Cardiovascular Medicine, University of Wisconsin-Madison School of Medicine and Public Health, Madison, Wisconsin
| | - J Carter Ralphe
- Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
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12
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Melby JA, de Lange WJ, Zhang J, Roberts DS, Mitchell SD, Tucholski T, Kim G, Kyrvasilis A, McIlwain SJ, Kamp TJ, Ralphe JC, Ge Y. Functionally Integrated Top-Down Proteomics for Standardized Assessment of Human Induced Pluripotent Stem Cell-Derived Engineered Cardiac Tissues. J Proteome Res 2021; 20:1424-1433. [PMID: 33395532 DOI: 10.1021/acs.jproteome.0c00830] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Three-dimensional (3D) human induced pluripotent stem cell-derived engineered cardiac tissues (hiPSC-ECTs) have emerged as a promising alternative to two-dimensional hiPSC-cardiomyocyte monolayer systems because hiPSC-ECTs are a closer representation of endogenous cardiac tissues and more faithfully reflect the relevant cardiac pathophysiology. The ability to perform functional and molecular assessments using the same hiPSC-ECT construct would allow for more reliable correlation between observed functional performance and underlying molecular events, and thus is critically needed. Herein, for the first time, we have established an integrated method that permits sequential assessment of functional properties and top-down proteomics from the same single hiPSC-ECT construct. We quantitatively determined the differences in isometric twitch force and the sarcomeric proteoforms between two groups of hiPSC-ECTs that differed in the duration of time of 3D-ECT culture. Importantly, by using this integrated method we discovered a new and strong correlation between the measured contractile parameters and the phosphorylation levels of alpha-tropomyosin between the two groups of hiPSC-ECTs. The integration of functional assessments together with molecular characterization by top-down proteomics in the same hiPSC-ECT construct enables a holistic analysis of hiPSC-ECTs to accelerate their applications in disease modeling, cardiotoxicity, and drug discovery. Data are available via ProteomeXchange with identifier PXD022814.
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Affiliation(s)
- Jake A Melby
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Willem J de Lange
- Department of Pediatrics, University of Wisconsin-Madison, Madison, Wisconsin 53705, United States
| | - Jianhua Zhang
- Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin 53705, United States
| | - David S Roberts
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Stanford D Mitchell
- Department of Cell and Regenerative Biology, University of Wisconsin-Madison, Madison, Wisconsin 53705, United States
| | - Trisha Tucholski
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Gina Kim
- Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin 53705, United States
| | - Andreas Kyrvasilis
- Department of Cell and Regenerative Biology, University of Wisconsin-Madison, Madison, Wisconsin 53705, United States
| | - Sean J McIlwain
- Department of Biostatistics and Medical Informatics, University of Wisconsin-Madison, Madison, Wisconsin 53705, United States.,UW Carbone Cancer Center, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin 53705, United States
| | - Timothy J Kamp
- Department of Cell and Regenerative Biology, University of Wisconsin-Madison, Madison, Wisconsin 53705, United States.,Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin 53705, United States
| | - J Carter Ralphe
- Department of Pediatrics, University of Wisconsin-Madison, Madison, Wisconsin 53705, United States
| | - Ying Ge
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States.,Department of Cell and Regenerative Biology, University of Wisconsin-Madison, Madison, Wisconsin 53705, United States.,Human Proteomics Program, University of Wisconsin-Madison, Madison, Wisconsin 53705, United States
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13
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Pricolo MR, Herrero-Galán E, Mazzaccara C, Losi MA, Alegre-Cebollada J, Frisso G. Protein Thermodynamic Destabilization in the Assessment of Pathogenicity of a Variant of Uncertain Significance in Cardiac Myosin Binding Protein C. J Cardiovasc Transl Res 2020; 13:867-877. [PMID: 32034629 DOI: 10.1007/s12265-020-09959-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Accepted: 01/20/2020] [Indexed: 12/29/2022]
Abstract
In the era of next generation sequencing (NGS), genetic testing for inherited disorders identifies an ever-increasing number of variants whose pathogenicity remains unclear. These variants of uncertain significance (VUS) limit the reach of genetic testing in clinical practice. The VUS for hypertrophic cardiomyopathy (HCM), the most common familial heart disease, constitute over 60% of entries for missense variants shown in ClinVar database. We have studied a novel VUS (c.1809T>G-p.I603M) in the most frequently mutated gene in HCM, MYBPC3, which codes for cardiac myosin-binding protein C (cMyBPC). Our determinations of pathogenicity integrate bioinformatics evaluation and functional studies of RNA splicing and protein thermodynamic stability. In silico prediction and mRNA analysis indicated no alteration of RNA splicing induced by the variant. At the protein level, the p.I603M mutation maps to the C4 domain of cMyBPC. Although the mutation does not perturb much the overall structure of the C4 domain, the stability of C4 I603M is severely compromised as detected by circular dichroism and differential scanning calorimetry experiments. Taking into account the highly destabilizing effect of the mutation in the structure of C4, we propose reclassification of variant p.I603M as likely pathogenic. Looking into the future, the workflow described here can be used to refine the assignment of pathogenicity of variants of uncertain significance in MYBPC3.
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Affiliation(s)
- Maria Rosaria Pricolo
- Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain. .,Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università Federico II, Naples, Italy.
| | - Elías Herrero-Galán
- Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain
| | - Cristina Mazzaccara
- Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università Federico II, Naples, Italy.,CEINGE Biotecnologie Avanzate s.c. a r.l., Naples, Italy
| | - Maria Angela Losi
- Dipartimento di Scienze Biomediche Avanzate, Università Federico II, Naples, Italy
| | | | - Giulia Frisso
- Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università Federico II, Naples, Italy.,CEINGE Biotecnologie Avanzate s.c. a r.l., Naples, Italy
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14
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Yu H, Ye F, Yuan F, Cai L, Ji H, Keller BB. Neonatal Murine Engineered Cardiac Tissue Toxicology Model: Impact of Metallothionein Overexpression on Cadmium-Induced Injury. Toxicol Sci 2019; 165:499-511. [PMID: 29982767 DOI: 10.1093/toxsci/kfy177] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Engineered cardiac tissues (ECTs) serve as robust in vitro models to study human cardiac diseases including cardiac toxicity assays due to rapid structural and functional maturation and the ability to vary ECT composition. Metallothionein (MT) has been shown to be cardioprotective for environmental toxicants including heavy metals. To date, studies on the role of cardiomyocyte (CM)-specific MT expression and function have occurred in dissociated single cell assays or expensive in vivo small animal models. Therefore, we generated 3D ECTs using neonatal mouse ventricular cells from wild-type (WT) and the CM-specific overexpressing MT-transgenic (MT-TG) to determine the effect of MT overexpression on ECT maturation and function. Because Cadmium (Cd) is an environmentally prevalent heavy metal toxicant with direct negative impact on cardiac structure and function, we then determined the effect of MT overexpression to reduce Cd mediated CM toxicity within ECTs. We found: (1) structural and functional maturation was similar in WT and MT-TG ECTs; (2) Cd exposure negatively impacted ECT cell survival, maturation, and function; and (3) MT-ECTs showed reduced Cd toxicity as defined by reduced cleaved caspase 3, reduced Bax/Bcl2 ratio, reduced TdT-mediated dUTP nick-end labeling positive cells, reduced CM loss after Cd treatment, and delayed onset of cardiac dysfunction after Cd treatment. Thus, neonatal murine ECTs can serve as a robust in vitro model for heavy metal toxicity screening and as a platform to evaluate the role cardioprotective mechanisms, such as the MT-TG model, on environmentally relevant toxicants.
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Affiliation(s)
- Haitao Yu
- The Center of Cardiovascular Disorders, The First Hospital of Jilin University, Changchun 130021, China.,The Pediatric Research Institute, The Department of Pediatrics of the University of Louisville, Louisville, Kentucky 40292
| | - Fei Ye
- The Center of Cardiovascular Disorders, The First Hospital of Jilin University, Changchun 130021, China.,Kosair Charities Pediatric Heart Research Program, Department of Pediatrics, Cardiovascular Innovation Institute, University of Louisville School of Medicine, Louisville, Kentucky 40202
| | - Fangping Yuan
- Kosair Charities Pediatric Heart Research Program, Department of Pediatrics, Cardiovascular Innovation Institute, University of Louisville School of Medicine, Louisville, Kentucky 40202
| | - Lu Cai
- The Pediatric Research Institute, The Department of Pediatrics of the University of Louisville, Louisville, Kentucky 40292.,Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky 40202
| | - Honglei Ji
- The Center of Cardiovascular Disorders, The First Hospital of Jilin University, Changchun 130021, China
| | - Bradley B Keller
- Kosair Charities Pediatric Heart Research Program, Department of Pediatrics, Cardiovascular Innovation Institute, University of Louisville School of Medicine, Louisville, Kentucky 40202.,Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky 40202
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15
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Doh CY, Li J, Mamidi R, Stelzer JE. The HCM-causing Y235S cMyBPC mutation accelerates contractile function by altering C1 domain structure. Biochim Biophys Acta Mol Basis Dis 2019; 1865:661-677. [PMID: 30611859 DOI: 10.1016/j.bbadis.2019.01.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Revised: 12/18/2018] [Accepted: 01/02/2019] [Indexed: 12/20/2022]
Abstract
Mutations in cardiac myosin binding protein C (cMyBPC) are a major cause of hypertrophic cardiomyopathy (HCM). In particular, a single amino acid substitution of tyrosine to serine at residue 237 in humans (residue 235 in mice) has been linked to HCM with strong disease association. Although cMyBPC truncations, deletions and insertions, and frame shift mutations have been studied, relatively little is known about the functional consequences of missense mutations in cMyBPC. In this study, we characterized the functional and structural effects of the HCM-causing Y235S mutation by performing mechanical experiments and molecular dynamics simulations (MDS). cMyBPC null mouse myocardium was virally transfected with wild-type (WT) or Y235S cMyBPC (KOY235S). We found that Y235S cMyBPC was properly expressed and incorporated into the cardiac sarcomere, suggesting that the mechanism of disease of the Y235S mutation is not haploinsufficiency or poison peptides. Mechanical experiments in detergent-skinned myocardium isolated from KOY235S hearts revealed hypercontractile behavior compared to KOWT hearts, evidenced by accelerated cross-bridge kinetics and increased Ca2+ sensitivity of force generation. In addition, MDS revealed that the Y235S mutation causes alterations in important intramolecular interactions, surface conformations, and electrostatic potential of the C1 domain of cMyBPC. Our combined in vitro and in silico data suggest that the Y235S mutation directly disrupts internal and surface properties of the C1 domain of cMyBPC, which potentially alters its ligand-binding interactions. These molecular changes may underlie the mechanism for hypercontractile cross-bridge behavior, which ultimately results in the development of cardiac hypertrophy and in vivo cardiac dysfunction.
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Affiliation(s)
- Chang Yoon Doh
- Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - Jiayang Li
- Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - Ranganath Mamidi
- Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - Julian E Stelzer
- Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University, Cleveland, OH, USA.
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