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Sun B, Kekenes-Huskey PM. Myofilament-associated proteins with intrinsic disorder (MAPIDs) and their resolution by computational modeling. Q Rev Biophys 2023; 56:e2. [PMID: 36628457 PMCID: PMC11070111 DOI: 10.1017/s003358352300001x] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The cardiac sarcomere is a cellular structure in the heart that enables muscle cells to contract. Dozens of proteins belong to the cardiac sarcomere, which work in tandem to generate force and adapt to demands on cardiac output. Intriguingly, the majority of these proteins have significant intrinsic disorder that contributes to their functions, yet the biophysics of these intrinsically disordered regions (IDRs) have been characterized in limited detail. In this review, we first enumerate these myofilament-associated proteins with intrinsic disorder (MAPIDs) and recent biophysical studies to characterize their IDRs. We secondly summarize the biophysics governing IDR properties and the state-of-the-art in computational tools toward MAPID identification and characterization of their conformation ensembles. We conclude with an overview of future computational approaches toward broadening the understanding of intrinsic disorder in the cardiac sarcomere.
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Affiliation(s)
- Bin Sun
- Research Center for Pharmacoinformatics (The State-Province Key Laboratories of Biomedicine-Pharmaceutics of China), Department of Medicinal Chemistry and Natural Medicine Chemistry, College of Pharmacy, Harbin Medical University, Harbin 150081, China
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2
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Mullins PD, Bondarenko VE. Mathematical model for β1-adrenergic regulation of the mouse ventricular myocyte contraction. Am J Physiol Heart Circ Physiol 2020; 318:H264-H282. [DOI: 10.1152/ajpheart.00492.2019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The β1-adrenergic regulation of cardiac myocyte contraction plays an important role in regulating heart function. Activation of this system leads to an increased heart rate and stronger myocyte contraction. However, chronic stimulation of the β1-adrenergic signaling system can lead to cardiac hypertrophy and heart failure. To understand the mechanisms of action of β1-adrenoceptors, a mathematical model of cardiac myocyte contraction that includes the β1-adrenergic system was developed and studied. The model was able to simulate major experimental protocols for measurements of steady-state force-calcium relationships, cross-bridge release rate and force development rate, force-velocity relationship, and force redevelopment rate. It also reproduced quite well frequency and isoproterenol dependencies for intracellular Ca2+ concentration ([Ca2+]i) transients, total contraction force, and sarcomere shortening. The mathematical model suggested the mechanisms of increased contraction force and myocyte shortening on stimulation of β1-adrenergic receptors is due to phosphorylation of troponin I and myosin-binding protein C and increased [Ca2+]i transient resulting from activation of the β1-adrenergic signaling system. The model was used to simulate work-loop contractions and estimate the power during the cardiac cycle as well as the effects of 4-aminopyridine and tedisamil on the myocyte contraction. The developed mathematical model can be used further for simulations of contraction of ventricular myocytes from genetically modified mice and myocytes from mice with chronic cardiac diseases. NEW & NOTEWORTHY A new mathematical model of mouse ventricular myocyte contraction that includes the β1-adrenergic system was developed. The model simulated major experimental protocols for myocyte contraction and predicted the effects of 4-aminopyridine and tedisamil on the myocyte contraction. The model also allowed for simulations of work-loop contractions and estimation of the power during the cardiac cycle.
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Affiliation(s)
- Paula D. Mullins
- Department of Mathematics, University of North Georgia, Blue Ridge, Georgia
- Department of Mathematics and Statistics and Neuroscience Institute, Georgia State University, Atlanta, Georgia
| | - Vladimir E. Bondarenko
- Department of Mathematics and Statistics and Neuroscience Institute, Georgia State University, Atlanta, Georgia
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Hoffmann J, Behnes M, Ansari U, Weidner K, Kuche P, Rusnak J, Kim SH, Natale M, Reckord N, Lang S, Hoffmann U, Bertsch T, Fatar M, Borggrefe M, Akin I. The association of high-sensitivity cardiac troponin I and T with echocardiographic stages of heart failure with preserved ejection fraction. Ann Clin Biochem 2019; 56:431-441. [PMID: 31112389 DOI: 10.1177/0004563219841644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background This study evaluates the associations between high-sensitivity troponin I and T (hs-TnI/hs-TnT) and the stages of heart failure with preserved ejection fraction (HFpEF)/diastolic dysfunction. Methods Blood samples for biomarker measurements (hs-TnI/hs-TnT/NT-proBNP) were collected within 24 h of routine echocardiographic examination. Patients with left ventricular ejection fraction <50%, right ventricular dysfunction and moderate-to-severe valvular heart disease were excluded. Graduation of diastolic dysfunction was determined according to current guidelines. Results A total of 70 patients were included. Hs-TnT concentrations increased significantly according to the progression of diastolic dysfunction ( P = 0.024). Hs-TnT was able to discriminate patients with diastolic dysfunction grade III (AUC = 0.737; P = 0.013), while NT-proBNP revealed a greater AUC (AUC 0.798; P = 0.002). Concentrations of hs-TnI increased only numerically according to the increasing stages of diastolic dysfunction ( P = 0.353). In multivariable logistic regression models, hs-TnT concentrations > 28 ng/L were associated with diastolic dysfunction grade III (OR = 4.7, P = 0.024), even after adjusting for NT-proBNP. Conclusion Increasing concentrations of hs-TnT may reflect the stages of diastolic dysfunction being assessed by echocardiography, whereas hs-TnI does not show any association with diastolic dysfunction.
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Affiliation(s)
- Julia Hoffmann
- 1 First Department of Medicine, Faculty of Medicine Mannheim, University Medical Centre Mannheim (UMM), University of Heidelberg, European Center for AngioScience (ECAS) and DZHK (German Center for Cardiovascular Research) partner site Heidelberg/Mannheim, Mannheim, Germany
| | - Michael Behnes
- 1 First Department of Medicine, Faculty of Medicine Mannheim, University Medical Centre Mannheim (UMM), University of Heidelberg, European Center for AngioScience (ECAS) and DZHK (German Center for Cardiovascular Research) partner site Heidelberg/Mannheim, Mannheim, Germany
| | - Uzair Ansari
- 1 First Department of Medicine, Faculty of Medicine Mannheim, University Medical Centre Mannheim (UMM), University of Heidelberg, European Center for AngioScience (ECAS) and DZHK (German Center for Cardiovascular Research) partner site Heidelberg/Mannheim, Mannheim, Germany
| | - Kathrin Weidner
- 1 First Department of Medicine, Faculty of Medicine Mannheim, University Medical Centre Mannheim (UMM), University of Heidelberg, European Center for AngioScience (ECAS) and DZHK (German Center for Cardiovascular Research) partner site Heidelberg/Mannheim, Mannheim, Germany
| | - Philip Kuche
- 1 First Department of Medicine, Faculty of Medicine Mannheim, University Medical Centre Mannheim (UMM), University of Heidelberg, European Center for AngioScience (ECAS) and DZHK (German Center for Cardiovascular Research) partner site Heidelberg/Mannheim, Mannheim, Germany
| | - Jonas Rusnak
- 1 First Department of Medicine, Faculty of Medicine Mannheim, University Medical Centre Mannheim (UMM), University of Heidelberg, European Center for AngioScience (ECAS) and DZHK (German Center for Cardiovascular Research) partner site Heidelberg/Mannheim, Mannheim, Germany
| | - Seung-Hyun Kim
- 1 First Department of Medicine, Faculty of Medicine Mannheim, University Medical Centre Mannheim (UMM), University of Heidelberg, European Center for AngioScience (ECAS) and DZHK (German Center for Cardiovascular Research) partner site Heidelberg/Mannheim, Mannheim, Germany
| | - Michele Natale
- 1 First Department of Medicine, Faculty of Medicine Mannheim, University Medical Centre Mannheim (UMM), University of Heidelberg, European Center for AngioScience (ECAS) and DZHK (German Center for Cardiovascular Research) partner site Heidelberg/Mannheim, Mannheim, Germany
| | - Nadine Reckord
- 1 First Department of Medicine, Faculty of Medicine Mannheim, University Medical Centre Mannheim (UMM), University of Heidelberg, European Center for AngioScience (ECAS) and DZHK (German Center for Cardiovascular Research) partner site Heidelberg/Mannheim, Mannheim, Germany
| | - Siegfried Lang
- 1 First Department of Medicine, Faculty of Medicine Mannheim, University Medical Centre Mannheim (UMM), University of Heidelberg, European Center for AngioScience (ECAS) and DZHK (German Center for Cardiovascular Research) partner site Heidelberg/Mannheim, Mannheim, Germany
| | - Ursula Hoffmann
- 1 First Department of Medicine, Faculty of Medicine Mannheim, University Medical Centre Mannheim (UMM), University of Heidelberg, European Center for AngioScience (ECAS) and DZHK (German Center for Cardiovascular Research) partner site Heidelberg/Mannheim, Mannheim, Germany
| | - Thomas Bertsch
- 2 Institute of Clinical Chemistry, Laboratory Medicine and Transfusion Medicine, General Hospital Nuremberg, Paracelsus Medical University, Germany
| | - Marc Fatar
- 3 Department of Neurology, University Medical Center Mannheim, University of Heidelberg, Mannheim, Germany
| | - Martin Borggrefe
- 1 First Department of Medicine, Faculty of Medicine Mannheim, University Medical Centre Mannheim (UMM), University of Heidelberg, European Center for AngioScience (ECAS) and DZHK (German Center for Cardiovascular Research) partner site Heidelberg/Mannheim, Mannheim, Germany
| | - Ibrahim Akin
- 1 First Department of Medicine, Faculty of Medicine Mannheim, University Medical Centre Mannheim (UMM), University of Heidelberg, European Center for AngioScience (ECAS) and DZHK (German Center for Cardiovascular Research) partner site Heidelberg/Mannheim, Mannheim, Germany
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4
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Li Y, Zhu G, Paolocci N, Zhang P, Takahashi C, Okumus N, Heravi A, Keceli G, Ramirez-Correa G, Kass DA, Murphy AM. Heart Failure-Related Hyperphosphorylation in the Cardiac Troponin I C Terminus Has Divergent Effects on Cardiac Function In Vivo. Circ Heart Fail 2017; 10:CIRCHEARTFAILURE.117.003850. [PMID: 28899987 PMCID: PMC5612410 DOI: 10.1161/circheartfailure.117.003850] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2017] [Accepted: 08/02/2017] [Indexed: 01/14/2023]
Abstract
BACKGROUND In human heart failure, Ser199 (equivalent to Ser200 in mouse) of cTnI (cardiac troponin I) is significantly hyperphosphorylated, and in vitro studies suggest that it enhances myofilament calcium sensitivity and alters calpain-mediated cTnI proteolysis. However, how its hyperphosphorylation affects cardiac function in vivo remains unknown. METHODS AND RESULTS To address the question, 2 transgenic mouse models were generated: a phospho-mimetic cTnIS200D and a phospho-silenced cTnIS200A, each driven by the cardiomyocyte-specific α-myosin heavy chain promoter. Cardiac structure assessed by echocardiography and histology was normal in both transgenic models compared with littermate controls (n=5). Baseline in vivo hemodynamics and isolated muscle studies showed that cTnIS200D significantly prolonged relaxation and lowered left ventricular peak filling rate, whereas ejection fraction and force development were normal (n=5). However, with increased heart rate or β-adrenergic stimulation, cTnIS200D mice had less enhanced ejection fraction or force development versus controls, whereas relaxation improved similarly to controls (n=5). By contrast, cTnIS200A was functionally normal both at baseline and under the physiological stresses. To test whether either mutation impacted cardiac response to ischemic stress, isolated hearts were subjected to ischemia/reperfusion. cTnIS200D were protected, recovering 88±8% of contractile function versus 35±15% in littermate controls and 28±8% in cTnIS200A (n=5). This was associated with less cTnI proteolysis in cTnIS200D hearts. CONCLUSIONS Hyperphosphorylation of this serine in cTnI C terminus impacts heart function by depressing diastolic function at baseline and limiting systolic reserve under physiological stresses. However, paradoxically, it preserves heart function after ischemia/reperfusion injury, potentially by decreasing proteolysis of cTnI.
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Affiliation(s)
- Yuejin Li
- Department of Pediatrics/Division of Cardiology, Johns Hopkins University, Baltimore, MD
| | - Guangshuo Zhu
- Department of Medicine/Division of Cardiology, Johns Hopkins University, Baltimore, MD
| | - Nazareno Paolocci
- Department of Medicine/Division of Cardiology, Johns Hopkins University, Baltimore, MD
| | - Pingbo Zhang
- Deparment of Ophthalmology, Johns Hopkins University, Baltimore, MD
| | - Cyrus Takahashi
- Department of Medicine/Division of Cardiology, Johns Hopkins University, Baltimore, MD
| | - Nazli Okumus
- Department of Pediatrics/Division of Cardiology, Johns Hopkins University, Baltimore, MD,Istanbul Faculty of Medicine, Istanbul, Turkey
| | - Amir Heravi
- Department of Pediatrics/Division of Cardiology, Johns Hopkins University, Baltimore, MD
| | - Gizem Keceli
- Department of Medicine/Division of Cardiology, Johns Hopkins University, Baltimore, MD
| | - Genaro Ramirez-Correa
- Department of Pediatrics/Division of Cardiology, Johns Hopkins University, Baltimore, MD
| | - David A Kass
- Department of Medicine/Division of Cardiology, Johns Hopkins University, Baltimore, MD,Department of Pharmacology and Molecular Sciences, Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD
| | - Anne M Murphy
- Department of Pediatrics/Division of Cardiology, Johns Hopkins University, Baltimore, MD
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Westfall MV. Contribution of Post-translational Phosphorylation to Sarcomere-Linked Cardiomyopathy Phenotypes. Front Physiol 2016; 7:407. [PMID: 27683560 PMCID: PMC5021686 DOI: 10.3389/fphys.2016.00407] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 08/30/2016] [Indexed: 01/24/2023] Open
Abstract
Secondary shifts develop in post-translational phosphorylation of sarcomeric proteins in multiple animal models of inherited cardiomyopathy. These signaling alterations together with the primary mutation are predicted to contribute to the overall cardiac phenotype. As a result, identification and integration of post-translational myofilament signaling responses are identified as priorities for gaining insights into sarcomeric cardiomyopathies. However, significant questions remain about the nature and contribution of post-translational phosphorylation to structural remodeling and cardiac dysfunction in animal models and human patients. This perspective essay discusses specific goals for filling critical gaps about post-translational signaling in response to these inherited mutations, especially within sarcomeric proteins. The discussion focuses primarily on pre-clinical analysis of animal models and defines challenges and future directions in this field.
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6
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Cheng Y, Lindert S, Oxenford L, Tu AY, McCulloch AD, Regnier M. Effects of Cardiac Troponin I Mutation P83S on Contractile Properties and the Modulation by PKA-Mediated Phosphorylation. J Phys Chem B 2016; 120:8238-53. [PMID: 27150586 PMCID: PMC5001945 DOI: 10.1021/acs.jpcb.6b01859] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
cTnI(P82S) (cTnI(P83S) in rodents) resides at the I-T arm of cardiac troponin I (cTnI) and was initially identified as a disease-causing mutation of hypertrophic cardiomyopathy (HCM). However, later studies suggested this may not be true. We recently reported that introduction of an HCM-associated mutation in either inhibitory-peptide (cTnI(R146G)) or cardiac-specific N-terminus (cTnI(R21C)) of cTnI blunts the PKA-mediated modulation on myofibril activation/relaxation kinetics by prohibiting formation of intrasubunit contacts between these regions. Here, we tested whether this also occurs for cTnI(P83S). cTnI(P83S) increased both Ca(2+) binding affinity to cTn (KCa) and affinity of cTnC for cTnI (KC-I), and eliminated the reduction of KCa and KC-I observed for phosphorylated-cTnI(WT). In isolated myofibrils, cTnI(P83S) maintained maximal tension (TMAX) and Ca(2+) sensitivity of tension (pCa50). For cTnI(WT) myofibrils, PKA-mediated phosphorylation decreased pCa50 and sped up the slow-phase relaxation (especially for those Ca(2+) conditions that heart performs in vivo). Those effects were blunted for cTnI(P83S) myofibrils. Molecular-dynamics simulations suggested cTnI(P83S) moderately inhibited an intrasubunit interaction formation between inhibitory-peptide and N-terminus, but this "blunting" effect was weaker than that with cTnI(R146G) or cTnI(R21C). In summary, cTnI(P83S) has similar effects as other HCM-associated cTnI mutations on troponin and myofibril function even though it is in the I-T arm of cTnI.
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Affiliation(s)
- Yuanhua Cheng
- Department of Bioengineering, University of Washington, Seattle, Washington 98105, United States
- National Biomedical Computation Resource, University of California San Diego, La Jolla, California 92093, United States
| | - Steffen Lindert
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Lucas Oxenford
- Department of Bioengineering, University of Washington, Seattle, Washington 98105, United States
| | - An-yue Tu
- Department of Bioengineering, University of Washington, Seattle, Washington 98105, United States
| | - Andrew D. McCulloch
- National Biomedical Computation Resource, University of California San Diego, La Jolla, California 92093, United States
- Department of Bioengineering, University of California San Diego, La Jolla, California 92093, United States
| | - Michael Regnier
- Department of Bioengineering, University of Washington, Seattle, Washington 98105, United States
- Center for Cardiovascular Biology, University of Washington, Seattle, Washington 98195, United States
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7
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Toepfer CN, Sikkel MB, Caorsi V, Vydyanath A, Torre I, Copeland O, Lyon AR, Marston SB, Luther PK, Macleod KT, West TG, Ferenczi MA. A post-MI power struggle: adaptations in cardiac power occur at the sarcomere level alongside MyBP-C and RLC phosphorylation. Am J Physiol Heart Circ Physiol 2016; 311:H465-75. [PMID: 27233767 PMCID: PMC5005282 DOI: 10.1152/ajpheart.00899.2015] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Accepted: 05/24/2016] [Indexed: 01/25/2023]
Abstract
Myocardial remodeling in response to chronic myocardial infarction (CMI) progresses through two phases, hypertrophic "compensation" and congestive "decompensation." Nothing is known about the ability of uninfarcted myocardium to produce force, velocity, and power during these clinical phases, even though adaptation in these regions likely drives progression of compensation. We hypothesized that enhanced cross-bridge-level contractility underlies mechanical compensation and is controlled in part by changes in the phosphorylation states of myosin regulatory proteins. We induced CMI in rats by left anterior descending coronary artery ligation. We then measured mechanical performance in permeabilized ventricular trabecula taken distant from the infarct zone and assayed myosin regulatory protein phosphorylation in each individual trabecula. During full activation, the compensated myocardium produced twice as much power and 31% greater isometric force compared with noninfarcted controls. Isometric force during submaximal activations was raised >2.4-fold, while power was 2-fold greater. Electron and confocal microscopy demonstrated that these mechanical changes were not a result of increased density of contractile protein and therefore not an effect of tissue hypertrophy. Hence, sarcomere-level contractile adaptations are key determinants of enhanced trabecular mechanics and of the overall cardiac compensatory response. Phosphorylation of myosin regulatory light chain (RLC) increased and remained elevated post-MI, while phosphorylation of myosin binding protein-C (MyBP-C) was initially depressed but then increased as the hearts became decompensated. These sensitivities to CMI are in accordance with phosphorylation-dependent regulatory roles for RLC and MyBP-C in crossbridge function and with compensatory adaptation in force and power that we observed in post-CMI trabeculae.
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Affiliation(s)
- Christopher N Toepfer
- Molecular Medicine Section, National Heart and Lung Institute, Imperial College London, London, United Kingdom; Laboratory of Molecular Physiology, National Heart and Lung Institute, National Institutes of Health, Bethesda, Maryland;
| | - Markus B Sikkel
- Department of Cardiac Medicine, National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Valentina Caorsi
- Molecular Medicine Section, National Heart and Lung Institute, Imperial College London, London, United Kingdom; Laboratoire Physico-Chimie, UMR168, Institute Curie, Paris, France
| | - Anupama Vydyanath
- Molecular Medicine Section, National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Iratxe Torre
- Molecular Medicine Section, National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - O'Neal Copeland
- Department of Cardiac Medicine, National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Alexander R Lyon
- Department of Cardiac Medicine, National Heart and Lung Institute, Imperial College London, London, United Kingdom; Nationa Institute of Health Research Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, United Kingdom
| | - Steven B Marston
- Department of Cardiac Medicine, National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Pradeep K Luther
- Molecular Medicine Section, National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Kenneth T Macleod
- Department of Cardiac Medicine, National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Timothy G West
- Royal Veterinary College London, Structure & Motion Laboratory, North Mymms, United Kingdom; and
| | - Michael A Ferenczi
- Molecular Medicine Section, National Heart and Lung Institute, Imperial College London, London, United Kingdom; Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore
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Cheng Y, Regnier M. Cardiac troponin structure-function and the influence of hypertrophic cardiomyopathy associated mutations on modulation of contractility. Arch Biochem Biophys 2016; 601:11-21. [PMID: 26851561 PMCID: PMC4899195 DOI: 10.1016/j.abb.2016.02.004] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2015] [Revised: 01/30/2016] [Accepted: 02/02/2016] [Indexed: 11/29/2022]
Abstract
Cardiac troponin (cTn) acts as a pivotal regulator of muscle contraction and relaxation and is composed of three distinct subunits (cTnC: a highly conserved Ca(2+) binding subunit, cTnI: an actomyosin ATPase inhibitory subunit, and cTnT: a tropomyosin binding subunit). In this mini-review, we briefly summarize the structure-function relationship of cTn and its subunits, its modulation by PKA-mediated phosphorylation of cTnI, and what is known about how these properties are altered by hypertrophic cardiomyopathy (HCM) associated mutations of cTnI. This includes recent work using computational modeling approaches to understand the atomic-based structural level basis of disease-associated mutations. We propose a viewpoint that it is alteration of cTnC-cTnI interaction (rather than the Ca(2+) binding properties of cTn) per se that disrupt the ability of PKA-mediated phosphorylation at cTnI Ser-23/24 to alter contraction and relaxation in at least some HCM-associated mutations. The combination of state of the art biophysical approaches can provide new insight on the structure-function mechanisms of contractile dysfunction resulting cTnI mutations and exciting new avenues for the diagnosis, prevention, and even treatment of heart diseases.
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Affiliation(s)
- Yuanhua Cheng
- University of Washington, Department of Bioengineering, Seattle, WA, USA
| | - Michael Regnier
- University of Washington, Department of Bioengineering, Seattle, WA, USA.
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Ntelios D, Tzimagiorgis G, Efthimiadis GK, Karvounis H. Mechanical aberrations in hypetrophic cardiomyopathy: emerging concepts. Front Physiol 2015; 6:232. [PMID: 26347658 PMCID: PMC4541419 DOI: 10.3389/fphys.2015.00232] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Accepted: 08/03/2015] [Indexed: 11/13/2022] Open
Abstract
Hypertrophic cardiomyopathy is the most common monogenic disorder in cardiology. Despite important advances in understanding disease pathogenesis, it is not clear how flaws in individual sarcomere components are responsible for the observed phenotype. The aim of this article is to provide a brief interpretative analysis of some currently proposed pathophysiological mechanisms of hypertrophic cardiomyopathy, with a special emphasis on alterations in the cardiac mechanical properties.
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Affiliation(s)
- Dimitrios Ntelios
- Laboratory of Biological Chemistry, Medical School, Aristotle University of Thessaloniki Thessaloniki, Greece ; Department of Cardiology, AHEPA University Hospital Thessaloniki, Greece
| | - Georgios Tzimagiorgis
- Laboratory of Biological Chemistry, Medical School, Aristotle University of Thessaloniki Thessaloniki, Greece
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