1
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Chinthalapudi K, Heissler SM. Structure, regulation, and mechanisms of nonmuscle myosin-2. Cell Mol Life Sci 2024; 81:263. [PMID: 38878079 PMCID: PMC11335295 DOI: 10.1007/s00018-024-05264-6] [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: 03/11/2024] [Revised: 04/24/2024] [Accepted: 04/30/2024] [Indexed: 06/23/2024]
Abstract
Members of the myosin superfamily of molecular motors are large mechanochemical ATPases that are implicated in an ever-expanding array of cellular functions. This review focuses on mammalian nonmuscle myosin-2 (NM2) paralogs, ubiquitous members of the myosin-2 family of filament-forming motors. Through the conversion of chemical energy into mechanical work, NM2 paralogs remodel and shape cells and tissues. This process is tightly controlled in time and space by numerous synergetic regulation mechanisms to meet cellular demands. We review how recent advances in structural biology together with elegant biophysical and cell biological approaches have contributed to our understanding of the shared and unique mechanisms of NM2 paralogs as they relate to their kinetics, regulation, assembly, and cellular function.
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Affiliation(s)
- Krishna Chinthalapudi
- Department of Physiology and Cell Biology, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University College of Medicine, Columbus, OH, 43210, USA
| | - Sarah M Heissler
- Department of Physiology and Cell Biology, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University College of Medicine, Columbus, OH, 43210, USA.
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2
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Buvoli M, Wilson GC, Buvoli A, Gugel JF, Hau A, Bönnemann CG, Paradas C, Ryba DM, Woulfe KC, Walker LA, Buvoli T, Ochala J, Leinwand LA. A Laing distal myopathy-associated proline substitution in the β-myosin rod perturbs myosin cross-bridging activity. J Clin Invest 2024; 134:e172599. [PMID: 38690726 PMCID: PMC11060730 DOI: 10.1172/jci172599] [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: 06/22/2023] [Accepted: 03/11/2024] [Indexed: 05/03/2024] Open
Abstract
Proline substitutions within the coiled-coil rod region of the β-myosin gene (MYH7) are the predominant mutations causing Laing distal myopathy (MPD1), an autosomal dominant disorder characterized by progressive weakness of distal/proximal muscles. We report that the MDP1 mutation R1500P, studied in what we believe to be the first mouse model for the disease, adversely affected myosin motor activity despite being in the structural rod domain that directs thick filament assembly. Contractility experiments carried out on isolated mutant muscles, myofibrils, and myofibers identified muscle fatigue and weakness phenotypes, an increased rate of actin-myosin detachment, and a conformational shift of the myosin heads toward the more reactive disordered relaxed (DRX) state, causing hypercontractility and greater ATP consumption. Similarly, molecular analysis of muscle biopsies from patients with MPD1 revealed a significant increase in sarcomeric DRX content, as observed in a subset of myosin motor domain mutations causing hypertrophic cardiomyopathy. Finally, oral administration of MYK-581, a small molecule that decreases the population of heads in the DRX configuration, significantly improved the limited running capacity of the R1500P-transgenic mice and corrected the increased DRX state of the myofibrils from patients. These studies provide evidence of the molecular pathogenesis of proline rod mutations and lay the groundwork for the therapeutic advancement of myosin modulators.
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Affiliation(s)
- Massimo Buvoli
- Department of Molecular, Cellular and Developmental Biology, and
- BioFrontiers Institute, Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder, Colorado, USA
| | - Genevieve C.K. Wilson
- Department of Molecular, Cellular and Developmental Biology, and
- BioFrontiers Institute, Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder, Colorado, USA
| | - Ada Buvoli
- Department of Molecular, Cellular and Developmental Biology, and
- BioFrontiers Institute, Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder, Colorado, USA
| | - Jack F. Gugel
- Department of Molecular, Cellular and Developmental Biology, and
- BioFrontiers Institute, Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder, Colorado, USA
| | - Abbi Hau
- Centre of Human and Applied Physiological Sciences, School of Basic and Medical Biosciences, Faculty of Life Sciences and Medicine, and
- Randall Centre for Cell and Molecular Biophysics, School of Basic and Medical Biosciences, Faculty of Life Sciences and Medicine, Guy’s Campus, King’s College London, London, United Kingdom
| | - Carsten G. Bönnemann
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke (NINDS), NIH, Bethesda, Maryland, USA
| | - Carmen Paradas
- Neuromuscular Unit, Department of Neurology, Instituto de Biomedicina de Sevilla (IBIS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Sevilla, Spain
| | | | - Kathleen C. Woulfe
- Division of Cardiology, Department of Medicine, University of Colorado, Denver, Colorado, USA
| | - Lori A. Walker
- Division of Cardiology, Department of Medicine, University of Colorado, Denver, Colorado, USA
| | - Tommaso Buvoli
- Department of Mathematics, Tulane University, New Orleans, Louisiana, USA
| | - Julien Ochala
- Centre of Human and Applied Physiological Sciences, School of Basic and Medical Biosciences, Faculty of Life Sciences and Medicine, and
- Randall Centre for Cell and Molecular Biophysics, School of Basic and Medical Biosciences, Faculty of Life Sciences and Medicine, Guy’s Campus, King’s College London, London, United Kingdom
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Leslie A. Leinwand
- Department of Molecular, Cellular and Developmental Biology, and
- BioFrontiers Institute, Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder, Colorado, USA
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3
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Casas-Mao D, Carrington G, Pujol MG, Peckham M. Effects of specific disease mutations in non-muscle myosin 2A on its structure and function. J Biol Chem 2024; 300:105514. [PMID: 38042490 PMCID: PMC10770755 DOI: 10.1016/j.jbc.2023.105514] [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: 08/31/2023] [Revised: 11/17/2023] [Accepted: 11/21/2023] [Indexed: 12/04/2023] Open
Abstract
Non-muscle myosin 2A (NM2A), a widely expressed class 2 myosin, is important for organizing actin filaments in cells. It cycles between a compact inactive 10S state in which its regulatory light chain (RLC) is dephosphorylated and a filamentous state in which the myosin heads interact with actin, and the RLC is phosphorylated. Over 170 missense mutations in MYH9, the gene that encodes the NM2A heavy chain, have been described. These cause MYH9 disease, an autosomal-dominant disorder that leads to bleeding disorders, kidney disease, cataracts, and deafness. Approximately two-thirds of these mutations occur in the coiled-coil tail. These mutations could destabilize the 10S state and/or disrupt filament formation or both. To test this, we determined the effects of six specific mutations using multiple approaches, including circular dichroism to detect changes in secondary structure, negative stain electron microscopy to analyze 10S and filament formation in vitro, and imaging of GFP-NM2A in fixed and live cells to determine filament assembly and dynamics. Two mutations in D1424 (D1424G and D1424N) and V1516M strongly decrease 10S stability and have limited effects on filament formation in vitro. In contrast, mutations in D1447 and E1841K, decrease 10S stability less strongly but increase filament lengths in vitro. The dynamic behavior of all mutants was altered in cells. Thus, the positions of mutated residues and their roles in filament formation and 10S stabilization are key to understanding their contributions to NM2A in disease.
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Affiliation(s)
- David Casas-Mao
- Astbury Centre for Structural Molecular Biology & School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK
| | - Glenn Carrington
- Astbury Centre for Structural Molecular Biology & School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK
| | - Marta Giralt Pujol
- Astbury Centre for Structural Molecular Biology & School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK
| | - Michelle Peckham
- Astbury Centre for Structural Molecular Biology & School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK.
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4
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Carrington G, Hau A, Kosta S, Dugdale HF, Muntoni F, D’Amico A, Van den Bergh P, Romero NB, Malfatti E, Vilchez JJ, Oldfors A, Pajusalu S, Õunap K, Giralt-Pujol M, Zanoteli E, Campbell KS, Iwamoto H, Peckham M, Ochala J. Human skeletal myopathy myosin mutations disrupt myosin head sequestration. JCI Insight 2023; 8:e172322. [PMID: 37788100 PMCID: PMC10721271 DOI: 10.1172/jci.insight.172322] [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: 05/15/2023] [Accepted: 09/20/2023] [Indexed: 10/05/2023] Open
Abstract
Myosin heavy chains encoded by MYH7 and MYH2 are abundant in human skeletal muscle and important for muscle contraction. However, it is unclear how mutations in these genes disrupt myosin structure and function leading to skeletal muscle myopathies termed myosinopathies. Here, we used multiple approaches to analyze the effects of common MYH7 and MYH2 mutations in the light meromyosin (LMM) region of myosin. Analyses of expressed and purified MYH7 and MYH2 LMM mutant proteins combined with in silico modeling showed that myosin coiled coil structure and packing of filaments in vitro are commonly disrupted. Using muscle biopsies from patients and fluorescent ATP analog chase protocols to estimate the proportion of myosin heads that were super-relaxed, together with x-ray diffraction measurements to estimate myosin head order, we found that basal myosin ATP consumption was increased and the myosin super-relaxed state was decreased in vivo. In addition, myofiber mechanics experiments to investigate contractile function showed that myofiber contractility was not affected. These findings indicate that the structural remodeling associated with LMM mutations induces a pathogenic state in which formation of shutdown heads is impaired, thus increasing myosin head ATP demand in the filaments, rather than affecting contractility. These key findings will help design future therapies for myosinopathies.
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Affiliation(s)
- Glenn Carrington
- The Astbury Centre for Structural and Molecular Biology and
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
| | - Abbi Hau
- Centre of Human and Applied Physiological Sciences and
- Randall Centre for Cell and Molecular Biophysics, School of Basic & Medical Biosciences, Faculty of Life Sciences & Medicine, King’s College London, United Kingdom
| | - Sarah Kosta
- Department of Physiology, University of Kentucky, Lexington, Kentucky, USA
| | - Hannah F. Dugdale
- Centre of Human and Applied Physiological Sciences and
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, United Kingdom
| | - Francesco Muntoni
- UCL Great Ormond Street Institute of Child Health, London, United Kingdom
- NIHR Biomedical Research Centre at Great Ormond Street Hospital, Great Ormond Street, London, United Kingdom
| | - Adele D’Amico
- Department of Neurosciences, Unit of Neuromuscular and Neurodegenerative Disorders, IRCCS Bambino Gesù Children’s Hospital, Rome, Italy
| | - Peter Van den Bergh
- Neuromuscular Reference Center, Neurology Department, University Hospital Saint-Luc, Brussels, Belgium
| | - Norma B. Romero
- Neuromuscular Morphology Unit, Institute of Myology, Myology Research Centre INSERM, Sorbonne University, Hôpital Pitié-Salpêtrière, Paris, France
| | - Edoardo Malfatti
- APHP, Centre de Référence de Pathologie Neuromusculaire Nord-Est-Ile-de-France, Henri Mondor Hospital, Inserm U955, Creteil, France
- U1179 UVSQ-INSERM Handicap Neuromuscular: Physiology, Biotherapy and Applied Pharmacology, UFR Simone Veil-Santé, Université Versailles Saint Quentin en Yvelines, Paris-Saclay, France
| | - Juan Jesus Vilchez
- Neuromuscular and Ataxias Research Group, Instituto de Investigación Sanitaria La Fe, Valencia, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER) Spain, Valencia, Spain
| | - Anders Oldfors
- Department of Laboratory Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Sander Pajusalu
- Genetics and Personalized Medicine Clinic, Tartu University Hospital, Tartu, Estonia
- Department of Clinical Genetics, Institute of Clinical Medicine, University of Tartu, Tartu, Estonia
| | - Katrin Õunap
- Genetics and Personalized Medicine Clinic, Tartu University Hospital, Tartu, Estonia
- Department of Clinical Genetics, Institute of Clinical Medicine, University of Tartu, Tartu, Estonia
| | - Marta Giralt-Pujol
- The Astbury Centre for Structural and Molecular Biology and
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
| | - Edmar Zanoteli
- Universidade de São Paulo, Hospital das Clínicas, Faculty of Medicine, Department of Neurology, São Paulo SP, Brazil
- Universidade Federal de São Paulo, Escola Paulista de Medicina, Department of Neurology, São Paulo SP, Brazil
| | - Kenneth S. Campbell
- Department of Physiology, University of Kentucky, Lexington, Kentucky, USA
- Division of Cardiovascular Medicine, University of Kentucky, Lexington, Kentucky, USA
| | - Hiroyuki Iwamoto
- SPring-8, Japan Synchrotron Radiation Research Institute, Hyogo, Japan
| | - Michelle Peckham
- The Astbury Centre for Structural and Molecular Biology and
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
| | - Julien Ochala
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
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5
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Dutta D, Nguyen V, Campbell KS, Padrón R, Craig R. Cryo-EM structure of the human cardiac myosin filament. Nature 2023; 623:853-862. [PMID: 37914935 PMCID: PMC10846670 DOI: 10.1038/s41586-023-06691-4] [Citation(s) in RCA: 32] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 09/28/2023] [Indexed: 11/03/2023]
Abstract
Pumping of the heart is powered by filaments of the motor protein myosin that pull on actin filaments to generate cardiac contraction. In addition to myosin, the filaments contain cardiac myosin-binding protein C (cMyBP-C), which modulates contractility in response to physiological stimuli, and titin, which functions as a scaffold for filament assembly1. Myosin, cMyBP-C and titin are all subject to mutation, which can lead to heart failure. Despite the central importance of cardiac myosin filaments to life, their molecular structure has remained a mystery for 60 years2. Here we solve the structure of the main (cMyBP-C-containing) region of the human cardiac filament using cryo-electron microscopy. The reconstruction reveals the architecture of titin and cMyBP-C and shows how myosin's motor domains (heads) form three different types of motif (providing functional flexibility), which interact with each other and with titin and cMyBP-C to dictate filament architecture and function. The packing of myosin tails in the filament backbone is also resolved. The structure suggests how cMyBP-C helps to generate the cardiac super-relaxed state3; how titin and cMyBP-C may contribute to length-dependent activation4; and how mutations in myosin and cMyBP-C might disturb interactions, causing disease5,6. The reconstruction resolves past uncertainties and integrates previous data on cardiac muscle structure and function. It provides a new paradigm for interpreting structural, physiological and clinical observations, and for the design of potential therapeutic drugs.
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Affiliation(s)
- Debabrata Dutta
- Division of Cell Biology and Imaging, Department of Radiology, University of Massachusetts Chan Medical School, Worcester, MA, USA.
| | - Vu Nguyen
- Division of Cell Biology and Imaging, Department of Radiology, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Kenneth S Campbell
- Department of Physiology and Division of Cardiovascular Medicine, University of Kentucky, Lexington, KY, USA
| | - Raúl Padrón
- Division of Cell Biology and Imaging, Department of Radiology, University of Massachusetts Chan Medical School, Worcester, MA, USA.
| | - Roger Craig
- Division of Cell Biology and Imaging, Department of Radiology, University of Massachusetts Chan Medical School, Worcester, MA, USA.
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6
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Sonne A, Antonovic AK, Melhedegaard E, Akter F, Andersen JL, Jungbluth H, Witting N, Vissing J, Zanoteli E, Fornili A, Ochala J. Abnormal myosin post-translational modifications and ATP turnover time associated with human congenital myopathy-related RYR1 mutations. Acta Physiol (Oxf) 2023; 239:e14035. [PMID: 37602753 PMCID: PMC10909445 DOI: 10.1111/apha.14035] [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: 05/30/2023] [Revised: 08/07/2023] [Accepted: 08/08/2023] [Indexed: 08/22/2023]
Abstract
AIM Conditions related to mutations in the gene encoding the skeletal muscle ryanodine receptor 1 (RYR1) are genetic muscle disorders and include congenital myopathies with permanent weakness, as well as episodic phenotypes such as rhabdomyolysis/myalgia. Although RYR1 dysfunction is the primary mechanism in RYR1-related disorders, other downstream pathogenic events are less well understood and may include a secondary remodeling of major contractile proteins. Hence, in the present study, we aimed to investigate whether congenital myopathy-related RYR1 mutations alter the regulation of the most abundant contractile protein, myosin. METHODS We used skeletal muscle tissues from five patients with RYR1-related congenital myopathy and compared those with five controls and five patients with RYR1-related rhabdomyolysis/myalgia. We then defined post-translational modifications on myosin heavy chains (MyHCs) using LC/MS. In parallel, we determined myosin relaxed states using Mant-ATP chase experiments and performed molecular dynamics (MD) simulations. RESULTS LC/MS revealed two additional phosphorylations (Thr1309-P and Ser1362-P) and one acetylation (Lys1410-Ac) on the β/slow MyHC of patients with congenital myopathy. This method also identified six acetylations that were lacking on MyHC type IIa of these patients (Lys35-Ac, Lys663-Ac, Lys763-Ac, Lys1171-Ac, Lys1360-Ac, and Lys1733-Ac). MD simulations suggest that modifying myosin Ser1362 impacts the protein structure and dynamics. Finally, Mant-ATP chase experiments showed a faster ATP turnover time of myosin heads in the disordered-relaxed conformation. CONCLUSIONS Altogether, our results suggest that RYR1 mutations have secondary negative consequences on myosin structure and function, likely contributing to the congenital myopathic phenotype.
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Affiliation(s)
- Alexander Sonne
- Department of Biomedical Sciences, Faculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
| | - Anna Katarina Antonovic
- Department of Chemistry, School of Physical and Chemical SciencesQueen Mary University of LondonLondonUK
| | - Elise Melhedegaard
- Department of Biomedical Sciences, Faculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
| | - Fariha Akter
- Department of Chemistry, School of Physical and Chemical SciencesQueen Mary University of LondonLondonUK
| | - Jesper L. Andersen
- Department of Orthopaedic Surgery, Institute of Sports Medicine CopenhagenCopenhagen University Hospital, Bispebjerg and FrederiksbergCopenhagenDenmark
- Center for Healthy Aging, Department of Clinical MedicineUniversity of CopenhagenCopenhagenDenmark
| | - Heinz Jungbluth
- Department of Paediatric NeurologyEvelina London Children's HospitalLondonUK
- Randall Centre for Cell and Molecular Biophysics, Muscle Signalling Section, Faculty of Life Sciences and MedicineKing's College LondonLondonUK
| | - Nanna Witting
- Copenhagen Neuromuscular Center, Department of NeurologyUniversity of CopenhagenCopenhagenDenmark
| | - John Vissing
- Copenhagen Neuromuscular Center, Department of NeurologyUniversity of CopenhagenCopenhagenDenmark
| | - Edmar Zanoteli
- Departamento de Neurologia, Faculdade de Medicina, Hospital das ClínicasUniversidade de São PauloSão PauloBrazil
| | - Arianna Fornili
- Department of Chemistry, School of Physical and Chemical SciencesQueen Mary University of LondonLondonUK
| | - Julien Ochala
- Department of Biomedical Sciences, Faculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
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7
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Dutta D, Nguyen V, Campbell KS, Padrón R, Craig R. Cryo-EM structure of the human cardiac myosin filament. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.11.536274. [PMID: 37090534 PMCID: PMC10120621 DOI: 10.1101/2023.04.11.536274] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/25/2023]
Abstract
Pumping of the heart is powered by filaments of the motor protein myosin, which pull on actin filaments to generate cardiac contraction. In addition to myosin, the filaments contain cardiac myosin-binding protein C (cMyBP-C), which modulates contractility in response to physiological stimuli, and titin, which functions as a scaffold for filament assembly 1 . Myosin, cMyBP-C and titin are all subject to mutation, which can lead to heart failure. Despite the central importance of cardiac myosin filaments to life, their molecular structure has remained a mystery for 60 years 2 . Here, we have solved the structure of the main (cMyBP-C-containing) region of the human cardiac filament to 6 Å resolution by cryo-EM. The reconstruction reveals the architecture of titin and cMyBP-C for the first time, and shows how myosin's motor domains (heads) form 3 different types of motif (providing functional flexibility), which interact with each other and with specific domains of titin and cMyBP-C to dictate filament architecture and regulate function. A novel packing of myosin tails in the filament backbone is also resolved. The structure suggests how cMyBP-C helps generate the cardiac super-relaxed state 3 , how titin and cMyBP-C may contribute to length-dependent activation 4 , and how mutations in myosin and cMyBP-C might disrupt interactions, causing disease 5, 6 . A similar structure is likely in vertebrate skeletal myosin filaments. The reconstruction resolves past uncertainties, and integrates previous data on cardiac muscle structure and function. It provides a new paradigm for interpreting structural, physiological and clinical observations, and for the design of potential therapeutic drugs.
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8
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Li J, Rahmani H, Abbasi Yeganeh F, Rastegarpouyani H, Taylor DW, Wood NB, Previs MJ, Iwamoto H, Taylor KA. Structure of the Flight Muscle Thick Filament from the Bumble Bee, Bombus ignitus, at 6 Å Resolution. Int J Mol Sci 2022; 24:377. [PMID: 36613818 PMCID: PMC9820631 DOI: 10.3390/ijms24010377] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 12/12/2022] [Accepted: 12/13/2022] [Indexed: 12/28/2022] Open
Abstract
Four insect orders have flight muscles that are both asynchronous and indirect; they are asynchronous in that the wingbeat frequency is decoupled from the frequency of nervous stimulation and indirect in that the muscles attach to the thoracic exoskeleton instead of directly to the wing. Flight muscle thick filaments from two orders, Hemiptera and Diptera, have been imaged at a subnanometer resolution, both of which revealed a myosin tail arrangement referred to as “curved molecular crystalline layers”. Here, we report a thick filament structure from the indirect flight muscles of a third insect order, Hymenoptera, the Asian bumble bee Bombus ignitus. The myosin tails are in general agreement with previous determinations from Lethocerus indicus and Drosophila melanogaster. The Skip 2 region has the same unusual structure as found in Lethocerus indicus thick filaments, an α-helix discontinuity is also seen at Skip 4, but the orientation of the Skip 1 region on the surface of the backbone is less angled with respect to the filament axis than in the other two species. The heads are disordered as in Drosophila, but we observe no non-myosin proteins on the backbone surface that might prohibit the ordering of myosin heads onto the thick filament backbone. There are strong structural similarities among the three species in their non-myosin proteins within the backbone that suggest how one previously unassigned density in Lethocerus might be assigned. Overall, the structure conforms to the previously observed pattern of high similarity in the myosin tail arrangement, but differences in the non-myosin proteins.
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Affiliation(s)
- Jiawei Li
- Institute of Molecular Biophysics, Florida State University, Tallahassee, FL 32306-4380, USA
| | - Hamidreza Rahmani
- Institute of Molecular Biophysics, Florida State University, Tallahassee, FL 32306-4380, USA
| | - Fatemeh Abbasi Yeganeh
- Institute of Molecular Biophysics, Florida State University, Tallahassee, FL 32306-4380, USA
| | - Hosna Rastegarpouyani
- Institute of Molecular Biophysics, Florida State University, Tallahassee, FL 32306-4380, USA
| | - Dianne W. Taylor
- Institute of Molecular Biophysics, Florida State University, Tallahassee, FL 32306-4380, USA
| | - Neil B. Wood
- Department of Molecular Physiology & Biophysics, University of Vermont, Larner College of Medicine, Burlington, VT 05405, USA
| | - Michael J. Previs
- Department of Molecular Physiology & Biophysics, University of Vermont, Larner College of Medicine, Burlington, VT 05405, USA
| | - Hiroyuki Iwamoto
- Scattering and Imaging Division, Japan Synchrotron Radiation Research Institute, SPring-8, Hyogo 679-5198, Japan
| | - Kenneth A. Taylor
- Institute of Molecular Biophysics, Florida State University, Tallahassee, FL 32306-4380, USA
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9
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Lilina AV, Leekens S, Hashim HM, Vermeire P, Harvey JN, Strelkov SV. Stability profile of vimentin rod domain. Protein Sci 2022; 31:e4505. [PMID: 36369679 PMCID: PMC9703591 DOI: 10.1002/pro.4505] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 11/02/2022] [Accepted: 11/06/2022] [Indexed: 11/14/2022]
Abstract
Intermediate filaments (IFs) form an essential part of the metazoan cytoskeleton. Despite a long history of research, a proper understanding of their molecular architecture and assembly process is still lacking. IFs self-assemble from elongated dimers, which are defined by their central "rod" domain. This domain forms an α-helical coiled coil consisting of three segments called coil1A, coil1B, and coil2. It has been hypothesized that the structural plasticity of the dimer, including the unraveling of some coiled-coil regions, is essential for the assembly process. To systematically explore this possibility, we have studied six 50-residue fragments covering the entire rod domain of human vimentin, a model IF protein. After creating in silico models of these fragments, their evaluation using molecular dynamics was performed. Large differences were seen across the six fragments with respect to their structural variability during a 100 ns simulation. Next, the fragments were prepared recombinantly, whereby their correct dimerization was promoted by adding short N- or C-terminal capping motifs. The capped fragments were subjected to circular dichroism measurements at varying temperatures. The obtained melting temperatures reveal the relative stabilities of individual fragments, which correlate well with in silico results. We show that the least stable regions of vimentin rod are coil1A and the first third of coil2, while the structures of coil1B and the rest of coil2 are significantly more robust. These observations are in line with the data obtained using other experimental approaches, and contribute to a better understanding of the molecular mechanisms driving IF assembly.
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Affiliation(s)
| | - Simon Leekens
- Laboratory for BiocrystallographyKU LeuvenLeuvenBelgium
| | - Hani M. Hashim
- Laboratory for BiocrystallographyKU LeuvenLeuvenBelgium
- Department of ChemistryKU LeuvenLeuvenBelgium
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10
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Liu JH, Yang HL, Deng ST, Hu Z, Chen WF, Yan WW, Hou RT, Li YH, Xian RT, Xie YY, Su Y, Wu LY, Xu P, Zhu ZB, Liu X, Deng YL, Wang YB, Liu Z, Fang WY. The small molecule chemical compound cinobufotalin attenuates resistance to DDP by inducing ENKUR expression to suppress MYH9-mediated c-Myc deubiquitination in lung adenocarcinoma. Acta Pharmacol Sin 2022; 43:2687-2695. [PMID: 35296779 PMCID: PMC9525298 DOI: 10.1038/s41401-022-00890-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Accepted: 02/15/2022] [Indexed: 12/11/2022] Open
Abstract
The small molecule chemical compound cinobufotalin (CB) is reported to be a potential antitumour drug that increases cisplatin (DDP) sensitivity in nasopharyngeal carcinoma. In this study, we first found that CB decreased DDP resistance, migration and invasion in lung adenocarcinoma (LUAD). Mechanistic studies showed that CB induced ENKUR expression by suppressing PI3K/AKT signalling to downregulate c-Jun, a negative transcription factor of ENKUR. Furthermore, ENKUR was shown to function as a tumour suppressor by binding to β-catenin to decrease c-Jun expression, thus suppressing MYH9 transcription. Interestingly, MYH9 is a binding protein of ENKUR. The Enkurin domain of ENKUR binds to MYH9, and the Myosin_tail of MYH9 binds to ENKUR. Downregulation of MYH9 reduced the recruitment of the deubiquitinase USP7, leading to increased c-Myc ubiquitination and degradation, decreased c-Myc nuclear translocation, and inactivation of epithelial-mesenchymal transition (EMT) signalling, thus attenuating DDP resistance. Our data demonstrated that CB is a promising antitumour drug and may be a candidate chemotherapeutic drug for LUAD patients.
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Affiliation(s)
- Jia-Hao Liu
- Cancer Center, Integrated Hospital of Traditional Chinese Medicine, Southern Medical University, Guangzhou, 510515, China
| | - Hui-Ling Yang
- Cancer Research Institute, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, China
- School of Pharmacy, Guangdong Medical University, Dongguan, 523808, China
| | - Shu-Ting Deng
- Cancer Center, Integrated Hospital of Traditional Chinese Medicine, Southern Medical University, Guangzhou, 510515, China
| | - Zhe Hu
- Cancer Center, Integrated Hospital of Traditional Chinese Medicine, Southern Medical University, Guangzhou, 510515, China
| | - Wei-Feng Chen
- Cancer Center, Integrated Hospital of Traditional Chinese Medicine, Southern Medical University, Guangzhou, 510515, China
| | - Wei-Wei Yan
- Cancer Center, Integrated Hospital of Traditional Chinese Medicine, Southern Medical University, Guangzhou, 510515, China
| | - Ren-Tao Hou
- Cancer Center, Integrated Hospital of Traditional Chinese Medicine, Southern Medical University, Guangzhou, 510515, China
| | - Yong-Hao Li
- Cancer Center, Integrated Hospital of Traditional Chinese Medicine, Southern Medical University, Guangzhou, 510515, China
| | - Rui-Ting Xian
- Cancer Center, Integrated Hospital of Traditional Chinese Medicine, Southern Medical University, Guangzhou, 510515, China
- Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China
| | - Ying-Ying Xie
- Cancer Center, Integrated Hospital of Traditional Chinese Medicine, Southern Medical University, Guangzhou, 510515, China
| | - Yun Su
- Key Laboratory of Protein Modification and Degradation, Basic School of Guangzhou Medical University, Guangzhou, 511436, China
| | - Li-Yang Wu
- Key Laboratory of Protein Modification and Degradation, Basic School of Guangzhou Medical University, Guangzhou, 511436, China
| | - Ping Xu
- Respiratory Department, Peking University Shenzhen Hospital, Shenzhen, 518034, China
| | - Zhi-Bo Zhu
- Cancer Center, Integrated Hospital of Traditional Chinese Medicine, Southern Medical University, Guangzhou, 510515, China
| | - Xiong Liu
- Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China
| | - Yu-Ling Deng
- Department of Chinese Medicine Rehabilitation, Pingxiang People's Hospital, Pingxiang, 337055, China
| | - Yu-Bing Wang
- Cancer Center, Integrated Hospital of Traditional Chinese Medicine, Southern Medical University, Guangzhou, 510515, China.
- Guangzhou Eighth People's Hospital, Guangzhou Medical University, Guangzhou, 510060, China.
| | - Zhen Liu
- Cancer Center, Integrated Hospital of Traditional Chinese Medicine, Southern Medical University, Guangzhou, 510515, China.
- Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China.
| | - Wei-Yi Fang
- Cancer Center, Integrated Hospital of Traditional Chinese Medicine, Southern Medical University, Guangzhou, 510515, China.
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11
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Zhang M, Sun X, Wu G, Wang D, Wang L, Zhang C, Zou Y, Wang J, Song L. Effect of Cis-Compound Variants in MYH7 on Hypertrophic Cardiomyopathy With a Mild Phenotype. Am J Cardiol 2022; 167:104-110. [PMID: 35065800 DOI: 10.1016/j.amjcard.2021.11.049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 11/17/2021] [Accepted: 11/22/2021] [Indexed: 11/29/2022]
Abstract
Patients with hypertrophic cardiomyopathy (HC) caused by compound variants have severe clinical manifestations, but significant clinical heterogeneity remains. Clinical diversity in these patients may result from different combinations of variants. We analyzed the role of cis-compound variants in a Chinese HC pedigree. Exome sequencing was performed in the proband. Identified variants were detected with bi-directional Sanger sequencing in a pedigree that comprised 3 generations and 28 family members. Follow-up was performed for 16 years. Two missense variants (c.2465T>C, p.Met822Thr; c.4258C>T, p.Arg1420Trp) were identified in the MYH7 gene. These variants were absent in our 761 in-house people without HC and predicted to be pathogenic.Both variants were detected in 11 family members, thus they were believed to inherit cis. In the 11 members, only 5 developed HC, the other 6 were asymptomatic variant carriers with an abnormal electrocardiogram. The HC members had mild hypertrophy with a maximum left ventricular wall thickness of 13 to 21 mm and showed a low incidence of cardiovascular events. In conclusion, the cis-compound variants of Met822Thr and Arg1420Trp in MYH7 are causal but relatively benign, variants associated with familial HC. This finding suggests that different types of compound variants might need to be analyzed for a genotype-phenotype study.
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Affiliation(s)
| | | | - Guixin Wu
- Department of Cardiology; State Key Laboratory of Cardiovascular Diseases
| | | | | | | | | | - Jizheng Wang
- State Key Laboratory of Cardiovascular Diseases.
| | - Lei Song
- Department of Cardiology; National Clinical Research Center of Cardiovascular Diseases, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
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12
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Landim-Vieira M, Childers MC, Wacker AL, Garcia MR, He H, Singh R, Brundage EA, Johnston JR, Whitson BA, Chase PB, Janssen PML, Regnier M, Biesiadecki BJ, Pinto JR, Parvatiyar MS. Post-translational modification patterns on β-myosin heavy chain are altered in ischemic and nonischemic human hearts. eLife 2022; 11:74919. [PMID: 35502901 PMCID: PMC9122498 DOI: 10.7554/elife.74919] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Accepted: 05/01/2022] [Indexed: 11/13/2022] Open
Abstract
Phosphorylation and acetylation of sarcomeric proteins are important for fine-tuning myocardial contractility. Here, we used bottom-up proteomics and label-free quantification to identify novel post-translational modifications (PTMs) on β-myosin heavy chain (β-MHC) in normal and failing human heart tissues. We report six acetylated lysines and two phosphorylated residues: K34-Ac, K58-Ac, S210-P, K213-Ac, T215-P, K429-Ac, K951-Ac, and K1195-Ac. K951-Ac was significantly reduced in both ischemic and nonischemic failing hearts compared to nondiseased hearts. Molecular dynamics (MD) simulations show that K951-Ac may impact stability of thick filament tail interactions and ultimately myosin head positioning. K58-Ac altered the solvent-exposed SH3 domain surface - known for protein-protein interactions - but did not appreciably change motor domain conformation or dynamics under conditions studied. Together, K213-Ac/T215-P altered loop 1's structure and dynamics - known to regulate ADP-release, ATPase activity, and sliding velocity. Our study suggests that β-MHC acetylation levels may be influenced more by the PTM location than the type of heart disease since less protected acetylation sites are reduced in both heart failure groups. Additionally, these PTMs have potential to modulate interactions between β-MHC and other regulatory sarcomeric proteins, ADP-release rate of myosin, flexibility of the S2 region, and cardiac myofilament contractility in normal and failing hearts.
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Affiliation(s)
- Maicon Landim-Vieira
- Department of Biomedical Sciences, College of Medicine, The Florida State UniversityTallahasseeUnited States
| | - Matthew C Childers
- Department of Bioengineering, College of Medicine, University of WashingtonSeattleUnited States
| | - Amanda L Wacker
- Department of Nutrition and Integrative Physiology, The Florida State UniversityTallahasseeUnited States
| | - Michelle Rodriquez Garcia
- Department of Biomedical Sciences, College of Medicine, The Florida State UniversityTallahasseeUnited States
| | - Huan He
- Department of Biomedical Sciences, College of Medicine, The Florida State UniversityTallahasseeUnited States,Translational Science Laboratory, College of Medicine, The Florida State UniversityTallahasseeUnited States
| | - Rakesh Singh
- Department of Biomedical Sciences, College of Medicine, The Florida State UniversityTallahasseeUnited States,Translational Science Laboratory, College of Medicine, The Florida State UniversityTallahasseeUnited States
| | - Elizabeth A Brundage
- Department of Physiology and Cell Biology, College of Medicine, The Ohio State UniversityColumbusUnited States
| | - Jamie R Johnston
- Department of Biomedical Sciences, College of Medicine, The Florida State UniversityTallahasseeUnited States
| | - Bryan A Whitson
- Department of Surgery, College of Medicine, The Ohio State UniversityColumbusUnited States
| | - P Bryant Chase
- Department of Biological Science, The Florida State UniversityTallahasseeUnited States
| | - Paul ML Janssen
- Department of Physiology and Cell Biology, College of Medicine, The Ohio State UniversityColumbusUnited States
| | - Michael Regnier
- Department of Bioengineering, College of Medicine, University of WashingtonSeattleUnited States
| | - Brandon J Biesiadecki
- Department of Physiology and Cell Biology, College of Medicine, The Ohio State UniversityColumbusUnited States
| | - J Renato Pinto
- Department of Biomedical Sciences, College of Medicine, The Florida State UniversityTallahasseeUnited States
| | - Michelle S Parvatiyar
- Department of Nutrition and Integrative Physiology, The Florida State UniversityTallahasseeUnited States
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13
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Seleit A, Aulehla A, Paix A. Endogenous protein tagging in medaka using a simplified CRISPR/Cas9 knock-in approach. eLife 2021; 10:75050. [PMID: 34870593 PMCID: PMC8691840 DOI: 10.7554/elife.75050] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 12/05/2021] [Indexed: 12/19/2022] Open
Abstract
The CRISPR/Cas9 system has been used to generate fluorescently labelled fusion proteins by homology-directed repair in a variety of species. Despite its revolutionary success, there remains an urgent need for increased simplicity and efficiency of genome editing in research organisms. Here, we establish a simplified, highly efficient, and precise strategy for CRISPR/Cas9-mediated endogenous protein tagging in medaka (Oryzias latipes). We use a cloning-free approach that relies on PCR-amplified donor fragments containing the fluorescent reporter sequences flanked by short homology arms (30–40 bp), a synthetic single-guide RNA and Cas9 mRNA. We generate eight novel knock-in lines with high efficiency of F0 targeting and germline transmission. Whole genome sequencing results reveal single-copy integration events only at the targeted loci. We provide an initial characterization of these fusion protein lines, significantly expanding the repertoire of genetic tools available in medaka. In particular, we show that the mScarlet-pcna line has the potential to serve as an organismal-wide label for proliferative zones and an endogenous cell cycle reporter.
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Affiliation(s)
- Ali Seleit
- Developmental Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Alexander Aulehla
- Developmental Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Alexandre Paix
- Developmental Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
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14
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Atak E, Karaoğlu D, Serttürk S, Koyuncu Irmak D, Yenenler-Kutlu A. Performing the comparative analysis to understand the functional roles of genes in different pathways of cardiomyopathy disease. Meta Gene 2021. [DOI: 10.1016/j.mgene.2021.100975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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15
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Fong KK, Davis TN, Asbury CL. Microtubule pivoting enables mitotic spindle assembly in S. cerevisiae. J Cell Biol 2021; 220:211686. [PMID: 33464308 PMCID: PMC7814349 DOI: 10.1083/jcb.202007193] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 12/07/2020] [Accepted: 12/16/2020] [Indexed: 12/17/2022] Open
Abstract
To assemble a bipolar spindle, microtubules emanating from two poles must bundle into an antiparallel midzone, where plus end–directed motors generate outward pushing forces to drive pole separation. Midzone cross-linkers and motors display only modest preferences for antiparallel filaments, and duplicated poles are initially tethered together, an arrangement that instead favors parallel interactions. Pivoting of microtubules around spindle poles might help overcome this geometric bias, but the intrinsic pivoting flexibility of the microtubule–pole interface has not been directly measured, nor has its importance during early spindle assembly been tested. By measuring the pivoting of microtubules around isolated yeast spindle poles, we show that pivoting flexibility can be modified by mutating a microtubule-anchoring pole component, Spc110. By engineering mutants with different flexibilities, we establish the importance of pivoting in vivo for timely pole separation. Our results suggest that passive thermal pivoting can bring microtubules from side-by-side poles into initial contact, but active minus end–directed force generation will be needed to achieve antiparallel alignment.
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Affiliation(s)
- Kimberly K Fong
- Department of Physiology and Biophysics, University of Washington, Seattle, WA
| | - Trisha N Davis
- Department of Biochemistry, University of Washington, Seattle, WA
| | - Charles L Asbury
- Department of Physiology and Biophysics, University of Washington, Seattle, WA
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16
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Huang S, Wu Y, Chen S, Yang Y, Wang Y, Wang H, Li P, Zhuang J, Xia Y. Novel insertion mutation (Arg1822_Glu1823dup) in MYH6 coiled-coil domain causing familial atrial septal defect. Eur J Med Genet 2021; 64:104314. [PMID: 34481090 DOI: 10.1016/j.ejmg.2021.104314] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2021] [Revised: 07/28/2021] [Accepted: 08/18/2021] [Indexed: 11/30/2022]
Abstract
OBJECTIVE Atrial septal defect, secundum (ASD Ⅱ, OMIM: 603642) is the second common congenital heart defect (CHD) in China. However, the genetic etiology of familial ASD II remains elusive. METHODS AND RESULTS Using whole-exome sequencing (WES) and Sanger sequencing, we identified a novel myosin heavy chain 6 (MYH6) gene insertion variation, NM_002471.3: c.5465_5470dup (Arg1822_Glu1823dup), in a large Chinese Han family with ASD II. The variant Arg1822_Glu1823dup co-segregated with the disease in this family with autosomal dominant inheritance. The insertion variant located in the coiled-coil domain of the MYH6 protein, which is highly conserved across homologous myosin proteins and species. In transfected myoblast C2C12 cell lines, the MYH6 Arg1822_Glu1823dup variant significantly impaired myofibril formation and increased apoptosis but did not significantly reduce cell viability. Furthermore, molecular simulations revealed that the Arg1822_Glu1823dup variant impaired the myosin α-helix, increasing the stability of the coiled-coil myosin dimer, suggesting that this variant has an effect on the coiled-coil domain self-aggregation. These findings indicate that Arg1822_Glu1823dup variant plays a crucial role in the pathogenesis of ASD II. CONCLUSION Our findings expand the spectrum of MYH6 variations associated with familial ASD II and may provide a molecular basis in genetic counseling and prenatal diagnosis for this Chinses family.
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Affiliation(s)
- Shufang Huang
- Prenatal Diagnosis Center, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China; Department of Obstetrics and Gynecology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Yueheng Wu
- Guangdong Provincial Key Laboratory of South China Structural Heart Disease, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China; Research Department of Medical Sciences, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Shaoxian Chen
- Guangdong Provincial Key Laboratory of South China Structural Heart Disease, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China; Research Department of Medical Sciences, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Yongchao Yang
- Department of Cardiovascular Surgery of Guangdong Provincial Cardiovascular Disease Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China; Guangdong Provincial Key Laboratory of South China Structural Heart Disease, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Yonghua Wang
- Prenatal Diagnosis Center, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China; Department of Obstetrics and Gynecology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Haiping Wang
- Prenatal Diagnosis Center, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China; Department of Obstetrics and Gynecology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Ping Li
- Prenatal Diagnosis Center, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China; Department of Obstetrics and Gynecology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Jian Zhuang
- Department of Cardiovascular Surgery of Guangdong Provincial Cardiovascular Disease Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China; Guangdong Provincial Key Laboratory of South China Structural Heart Disease, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Yu Xia
- Department of Cardiovascular Surgery, Guangdong Provincial Hospital of Chinese Medicine, Guangzhou, China; The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China.
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17
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Menard LM, Wood NB, Vigoreaux JO. Contiguity and Structural Impacts of a Non-Myosin Protein within the Thick Filament Myosin Layers. BIOLOGY 2021; 10:biology10070613. [PMID: 34356468 PMCID: PMC8301149 DOI: 10.3390/biology10070613] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/30/2021] [Revised: 06/26/2021] [Accepted: 06/30/2021] [Indexed: 01/17/2023]
Abstract
Simple Summary Hexapods and crustaceans (Pancrustacea) represent nearly 80% of known living animals. Species within this clade exhibit exquisite muscle types propelling ingenious means of locomotion, likely contributing to their evolutionary success. Flightin, a myosin-binding protein, first identified in the flight muscle of Drosophila, is defined by WYR, a protein domain exclusive to Pancrustacea. In Drosophila, flightin imparts stiffness to the thick filament and is essential for their length determination and structural integrity. Here, we build on results from the three-dimensional reconstruction of the Lethocerus flight muscle thick filament to advance the hypothesis that flightin influences thick filament mechanics, and by extension muscle function, by acting as a cinch in the filament core. Abstract Myosin dimers arranged in layers and interspersed with non-myosin densities have been described by cryo-EM 3D reconstruction of the thick filament in Lethocerus at 5.5 Å resolution. One of the non-myosin densities, denoted the ‘red density’, is hypothesized to be flightin, an LMM-binding protein essential to the structure and function of Drosophila indirect flight muscle (IFM). Here, we build upon the 3D reconstruction results specific to the red density and its engagement with the myosin coiled-coil rods that form the backbone of the thick filament. Each independent red density winds its way through the myosin dimers, such that it links four dimers in a layer and one dimer in a neighboring layer. This area in which three distinct interfaces within the myosin rod are contacted at once and the red density extends to the thick filament core is designated the “multiface”. Present within the multiface is a contact area inclusive of E1563 and R1568. Mutations in the corresponding Drosophila residues (E1554K and R1559H) are known to interfere with flightin accumulation and phosphorylation in Drosophila. We further examine the LMM area in direct apposition to the red density and identified potential binding residues spanning up to ten helical turns. We find that the red density is associated within an expanse of the myosin coiled-coil that is unwound by the third skip residue and the coiled-coil is re-oriented while in contact with the red density. These findings suggest a mechanism by which flightin induces ordered assembly of myosin dimers through its contacts with multiple myosin dimers and brings about reinforcement on the level of a single myosin dimer by stabilization of the myosin coiled-coil.
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18
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Menard LM, Wood NB, Vigoreaux JO. Secondary Structure of the Novel Myosin Binding Domain WYR and Implications within Myosin Structure. BIOLOGY 2021; 10:603. [PMID: 34209926 PMCID: PMC8301185 DOI: 10.3390/biology10070603] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/30/2021] [Revised: 06/25/2021] [Accepted: 06/27/2021] [Indexed: 01/05/2023]
Abstract
Structural changes in the myosin II light meromyosin (LMM) that influence thick filament mechanical properties and muscle function are modulated by LMM-binding proteins. Flightin is an LMM-binding protein indispensable for the function of Drosophila indirect flight muscle (IFM). Flightin has a three-domain structure that includes WYR, a novel 52 aa domain conserved throughout Pancrustacea. In this study, we (i) test the hypothesis that WYR binds the LMM, (ii) characterize the secondary structure of WYR, and (iii) examine the structural impact WYR has on the LMM. Circular dichroism at 260-190 nm reveals a structural profile for WYR and supports an interaction between WYR and LMM. A WYR-LMM interaction is supported by co-sedimentation with a stoichiometry of ~2.4:1. The WYR-LMM interaction results in an overall increased coiled-coil content, while curtailing ɑ helical content. WYR is found to be composed of 15% turns, 31% antiparallel β, and 48% 'other' content. We propose a structural model of WYR consisting of an antiparallel β hairpin between Q92-K114 centered on an ASX or β turn around N102, with a G1 bulge at G117. The Drosophila LMM segment used, V1346-I1941, encompassing conserved skip residues 2-4, is found to possess a traditional helical profile but is interpreted as having <30% helical content by multiple methods of deconvolution. This low helicity may be affiliated with the dynamic behavior of the structure in solution or the inclusion of a known non-helical region in the C-terminus. Our results support the hypothesis that WYR binds the LMM and that this interaction brings about structural changes in the coiled-coil. These studies implicate flightin, via the WYR domain, for distinct shifts in LMM secondary structure that could influence the structural properties and stabilization of the thick filament, scaling to modulation of whole muscle function.
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Affiliation(s)
| | | | - Jim O. Vigoreaux
- Department of Biology, University of Vermont, Burlington, VT 05405, USA; (L.M.M.); (N.B.W.)
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19
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Reynolds N, Aceves NM, Liu JL, Compton JR, Leary DH, Freitas BT, Pegan SD, Doctor KZ, Wu FY, Hu X, Legler PM. The SARS-CoV-2 SSHHPS Recognized by the Papain-like Protease. ACS Infect Dis 2021; 7:1483-1502. [PMID: 34019767 PMCID: PMC8171221 DOI: 10.1021/acsinfecdis.0c00866] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Indexed: 12/16/2022]
Abstract
Viral proteases are highly specific and recognize conserved cleavage site sequences of ∼6-8 amino acids. Short stretches of homologous host-pathogen sequences (SSHHPS) can be found spanning the viral protease cleavage sites. We hypothesized that these sequences corresponded to specific host protein targets since >40 host proteins have been shown to be cleaved by Group IV viral proteases and one Group VI viral protease. Using PHI-BLAST and the viral protease cleavage site sequences, we searched the human proteome for host targets and analyzed the hit results. Although the polyprotein and host proteins related to the suppression of the innate immune responses may be the primary targets of these viral proteases, we identified other cleavable host proteins. These proteins appear to be related to the virus-induced phenotype associated with Group IV viruses, suggesting that information about viral pathogenesis may be extractable directly from the viral genome sequence. Here we identify sequences cleaved by the SARS-CoV-2 papain-like protease (PLpro) in vitro within human MYH7 and MYH6 (two cardiac myosins linked to several cardiomyopathies), FOXP3 (an X-linked Treg cell transcription factor), ErbB4 (HER4), and vitamin-K-dependent plasma protein S (PROS1), an anticoagulation protein that prevents blood clots. Zinc inhibited the cleavage of these host sequences in vitro. Other patterns emerged from multispecies sequence alignments of the cleavage sites, which may have implications for the selection of animal models and zoonosis. SSHHPS/nsP is an example of a sequence-specific post-translational silencing mechanism.
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Affiliation(s)
- Nathanael
D. Reynolds
- Center
for Bio/molecular Science and Engineering (CBMSE), U.S. Naval Research Laboratory, 4555 Overlook Avenue, Washington, DC 20375, United States
| | | | - Jinny L. Liu
- Center
for Bio/molecular Science and Engineering (CBMSE), U.S. Naval Research Laboratory, 4555 Overlook Avenue, Washington, DC 20375, United States
| | - Jaimee R. Compton
- Center
for Bio/molecular Science and Engineering (CBMSE), U.S. Naval Research Laboratory, 4555 Overlook Avenue, Washington, DC 20375, United States
| | - Dagmar H. Leary
- Center
for Bio/molecular Science and Engineering (CBMSE), U.S. Naval Research Laboratory, 4555 Overlook Avenue, Washington, DC 20375, United States
| | - Brendan T. Freitas
- Center
for Drug Discovery, College of Pharmacy, University of Georgia, Athens, Georgia 30602, United States
| | - Scott D. Pegan
- Center
for Drug Discovery, College of Pharmacy, University of Georgia, Athens, Georgia 30602, United States
| | - Katarina Z. Doctor
- Navy
Center for Applied Research in AI (NCARAI) Information Technology
Division, U.S. Naval Research Laboratory, 4555 Overlook Ave., Washington, DC 20375, United States
| | - Fred Y. Wu
- Indiana
University Health Systems, Indiana University
School of Medicine, Bloomington, Indiana 47401, United States
| | - Xin Hu
- National
Center for Advancing Translational Sciences, National Institutes of
Health, Rockville, Maryland 20850, United
States
| | - Patricia M. Legler
- Center
for Bio/molecular Science and Engineering (CBMSE), U.S. Naval Research Laboratory, 4555 Overlook Avenue, Washington, DC 20375, United States
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20
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Rahmani H, Ma W, Hu Z, Daneshparvar N, Taylor DW, McCammon JA, Irving TC, Edwards RJ, Taylor KA. The myosin II coiled-coil domain atomic structure in its native environment. Proc Natl Acad Sci U S A 2021; 118:e2024151118. [PMID: 33782130 PMCID: PMC8040620 DOI: 10.1073/pnas.2024151118] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The atomic structure of the complete myosin tail within thick filaments isolated from Lethocerus indicus flight muscle is described and compared to crystal structures of recombinant, human cardiac myosin tail segments. Overall, the agreement is good with three exceptions: the proximal S2, in which the filament has heads attached but the crystal structure doesn't, and skip regions 2 and 4. At the head-tail junction, the tail α-helices are asymmetrically structured encompassing well-defined unfolding of 12 residues for one myosin tail, ∼4 residues of the other, and different degrees of α-helix unwinding for both tail α-helices, thereby providing an atomic resolution description of coiled-coil "uncoiling" at the head-tail junction. Asymmetry is observed in the nonhelical C termini; one C-terminal segment is intercalated between ribbons of myosin tails, the other apparently terminating at Skip 4 of another myosin tail. Between skip residues, crystal and filament structures agree well. Skips 1 and 3 also agree well and show the expected α-helix unwinding and coiled-coil untwisting in response to skip residue insertion. Skips 2 and 4 are different. Skip 2 is accommodated in an unusual manner through an increase in α-helix radius and corresponding reduction in rise/residue. Skip 4 remains helical in one chain, with the other chain unfolded, apparently influenced by the acidic myosin C terminus. The atomic model may shed some light on thick filament mechanosensing and is a step in understanding the complex roles that thick filaments of all species undergo during muscle contraction.
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Affiliation(s)
- Hamidreza Rahmani
- Institute of Molecular Biophysics, Florida State University, Tallahassee, FL 32306-4380
- Department of Physics, Florida State University, Tallahassee, FL 32306-4380
| | - Wen Ma
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA 92093
| | - Zhongjun Hu
- Institute of Molecular Biophysics, Florida State University, Tallahassee, FL 32306-4380
| | - Nadia Daneshparvar
- Institute of Molecular Biophysics, Florida State University, Tallahassee, FL 32306-4380
- Department of Physics, Florida State University, Tallahassee, FL 32306-4380
| | - Dianne W Taylor
- Institute of Molecular Biophysics, Florida State University, Tallahassee, FL 32306-4380
| | - J Andrew McCammon
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA 92093
| | - Thomas C Irving
- Department of Biological Sciences, Illinois Institute of Technology, Chicago, IL 60616
| | - Robert J Edwards
- Department of Cell Biology, Duke University Medical Center, Durham, NC 27607
| | - Kenneth A Taylor
- Institute of Molecular Biophysics, Florida State University, Tallahassee, FL 32306-4380;
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21
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Brizendine RK, Anuganti M, Cremo CR. Evidence for S2 flexibility by direct visualization of quantum dot-labeled myosin heads and rods within smooth muscle myosin filaments moving on actin in vitro. J Gen Physiol 2021; 153:211680. [PMID: 33439241 PMCID: PMC7809879 DOI: 10.1085/jgp.202012751] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 11/18/2020] [Accepted: 12/10/2020] [Indexed: 12/21/2022] Open
Abstract
Myosins in muscle assemble into filaments by interactions between the C-terminal light meromyosin (LMM) subdomains of the coiled-coil rod domain. The two head domains are connected to LMM by the subfragment-2 (S2) subdomain of the rod. Our mixed kinetic model predicts that the flexibility and length of S2 that can be pulled away from the filament affects the maximum distance working heads can move a filament unimpeded by actin-attached heads. It also suggests that it should be possible to observe a head remain stationary relative to the filament backbone while bound to actin (dwell), followed immediately by a measurable jump upon detachment to regain the backbone trajectory. We tested these predictions by observing filaments moving along actin at varying ATP using TIRF microscopy. We simultaneously tracked two different color quantum dots (QDs), one attached to a regulatory light chain on the lever arm and the other attached to an LMM in the filament backbone. We identified events (dwells followed by jumps) by comparing the trajectories of the QDs. The average dwell times were consistent with known kinetics of the actomyosin system, and the distribution of the waiting time between observed events was consistent with a Poisson process and the expected ATPase rate. Geometric constraints suggest a maximum of ∼26 nm of S2 can be unzipped from the filament, presumably involving disruption in the coiled-coil S2, a result consistent with observations by others of S2 protruding from the filament in muscle. We propose that sufficient force is available from the working heads in the filament to overcome the stiffness imposed by filament-S2 interactions.
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Affiliation(s)
- Richard K Brizendine
- Department of Pharmacology, School of Medicine, University of Nevada, Reno, Reno, NV
| | - Murali Anuganti
- Department of Pharmacology, School of Medicine, University of Nevada, Reno, Reno, NV
| | - Christine R Cremo
- Department of Pharmacology, School of Medicine, University of Nevada, Reno, Reno, NV
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22
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Wang L, Chitano P, Seow CY. Filament evanescence of myosin II and smooth muscle function. J Gen Physiol 2021; 153:211814. [PMID: 33606000 PMCID: PMC7901143 DOI: 10.1085/jgp.202012781] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 01/19/2021] [Indexed: 01/02/2023] Open
Abstract
Smooth muscle is an integral part of hollow organs. Many of them are constantly subjected to mechanical forces that alter organ shape and modify the properties of smooth muscle. To understand the molecular mechanisms underlying smooth muscle function in its dynamic mechanical environment, a new paradigm has emerged that depicts evanescence of myosin filaments as a key mechanism for the muscle’s adaptation to external forces in order to maintain optimal contractility. Unlike the bipolar myosin filaments of striated muscle, the side-polar filaments of smooth muscle appear to be less stable, capable of changing their lengths through polymerization and depolymerization (i.e., evanescence). In this review, we summarize accumulated knowledge on the structure and mechanism of filament formation of myosin II and on the influence of ionic strength, pH, ATP, myosin regulatory light chain phosphorylation, and mechanical perturbation on myosin filament stability. We discuss the scenario of intracellular pools of monomeric and filamentous myosin, length distribution of myosin filaments, and the regulatory mechanisms of filament lability in contraction and relaxation of smooth muscle. Based on recent findings, we suggest that filament evanescence is one of the fundamental mechanisms underlying smooth muscle’s ability to adapt to the external environment and maintain optimal function. Finally, we briefly discuss how increased ROCK protein expression in asthma may lead to altered myosin filament stability, which may explain the lack of deep-inspiration–induced bronchodilation and bronchoprotection in asthma.
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Affiliation(s)
- Lu Wang
- Department of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.,The Centre for Heart Lung Innovation, University of British Columbia, Vancouver, British Columbia, Canada
| | - Pasquale Chitano
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, British Columbia, Canada.,The Centre for Heart Lung Innovation, University of British Columbia, Vancouver, British Columbia, Canada
| | - Chun Y Seow
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, British Columbia, Canada.,The Centre for Heart Lung Innovation, University of British Columbia, Vancouver, British Columbia, Canada
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23
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Yang S, Tiwari P, Lee KH, Sato O, Ikebe M, Padrón R, Craig R. Cryo-EM structure of the inhibited (10S) form of myosin II. Nature 2020; 588:521-525. [PMID: 33268893 PMCID: PMC7746622 DOI: 10.1038/s41586-020-3007-0] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 10/01/2020] [Indexed: 01/14/2023]
Abstract
Myosin II is the motor protein that enables muscle cells to contract and nonmuscle cells to move and change shape1. The molecule has two identical heads attached to an elongated tail, and can exist in two conformations: 10S and 6S, named for their sedimentation coefficients2,3. The 6S conformation has an extended tail and assembles into polymeric filaments, which pull on actin filaments to generate force and motion. In 10S myosin, the tail is folded into three segments and the heads bend back and interact with each other and the tail3-7, creating a compact conformation in which ATPase activity, actin activation and filament assembly are all highly inhibited7,8. This switched-off structure appears to function as a key energy-conserving storage molecule in muscle and nonmuscle cells9-12, which can be activated to form functional filaments as needed13-but the mechanism of its inhibition is not understood. Here we have solved the structure of smooth muscle 10S myosin by cryo-electron microscopy with sufficient resolution to enable improved understanding of the function of the head and tail regions of the molecule and of the key intramolecular contacts that cause inhibition. Our results suggest an atomic model for the off state of myosin II, for its activation and unfolding by phosphorylation, and for understanding the clustering of disease-causing mutations near sites of intramolecular interaction.
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Affiliation(s)
- Shixin Yang
- Division of Cell Biology and Imaging, Department of Radiology, University of Massachusetts Medical School, Worcester, MA, USA
- Cryo-EM Shared Resources, Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Prince Tiwari
- Division of Cell Biology and Imaging, Department of Radiology, University of Massachusetts Medical School, Worcester, MA, USA
| | - Kyoung Hwan Lee
- Division of Cell Biology and Imaging, Department of Radiology, University of Massachusetts Medical School, Worcester, MA, USA
- Massachusetts Facility for High-Resolution Electron Cryo-microscopy, University of Massachusetts Medical School, Worcester, MA, USA
| | - Osamu Sato
- Department of Cellular and Molecular Biology, University of Texas Health Science Center at Tyler, Tyler, TX, USA
| | - Mitsuo Ikebe
- Department of Cellular and Molecular Biology, University of Texas Health Science Center at Tyler, Tyler, TX, USA
| | - Raúl Padrón
- Division of Cell Biology and Imaging, Department of Radiology, University of Massachusetts Medical School, Worcester, MA, USA
| | - Roger Craig
- Division of Cell Biology and Imaging, Department of Radiology, University of Massachusetts Medical School, Worcester, MA, USA.
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24
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Sitbon YH, Yadav S, Kazmierczak K, Szczesna-Cordary D. Insights into myosin regulatory and essential light chains: a focus on their roles in cardiac and skeletal muscle function, development and disease. J Muscle Res Cell Motil 2020; 41:313-327. [PMID: 31131433 PMCID: PMC6879809 DOI: 10.1007/s10974-019-09517-x] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Accepted: 05/21/2019] [Indexed: 12/15/2022]
Abstract
The activity of cardiac and skeletal muscles depends upon the ATP-coupled actin-myosin interactions to execute the power stroke and muscle contraction. The goal of this review article is to provide insight into the function of myosin II, the molecular motor of the heart and skeletal muscles, with a special focus on the role of myosin II light chain (MLC) components. Specifically, we focus on the involvement of myosin regulatory (RLC) and essential (ELC) light chains in striated muscle development, isoform appearance and their function in normal and diseased muscle. We review the consequences of isoform switching and knockout of specific MLC isoforms on cardiac and skeletal muscle function in various animal models. Finally, we discuss how dysregulation of specific RLC/ELC isoforms can lead to cardiac and skeletal muscle diseases and summarize the effects of most studied mutations leading to cardiac or skeletal myopathies.
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Affiliation(s)
- Yoel H Sitbon
- Department of Molecular and Cellular Pharmacology, University of Miami Miller School of Medicine, 1600 NW 10th Ave, Miami, FL, 33136, USA
| | - Sunil Yadav
- Department of Molecular and Cellular Pharmacology, University of Miami Miller School of Medicine, 1600 NW 10th Ave, Miami, FL, 33136, USA
| | - Katarzyna Kazmierczak
- Department of Molecular and Cellular Pharmacology, University of Miami Miller School of Medicine, 1600 NW 10th Ave, Miami, FL, 33136, USA
| | - Danuta Szczesna-Cordary
- Department of Molecular and Cellular Pharmacology, University of Miami Miller School of Medicine, 1600 NW 10th Ave, Miami, FL, 33136, USA.
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25
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Kominami Y, Nakakubo H, Nakamizo R, Matsuoka Y, Ueki N, Wan J, Watabe S, Ushio H. Peptidomic Analysis of a Disintegrated Surimi Gel from Deep-Sea Bonefish Pterothrissus gissu. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:12683-12691. [PMID: 33112604 DOI: 10.1021/acs.jafc.0c04427] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Surimi gel is a commonly found gelled product in Japan. Disintegration of the surimi gel is mainly caused by proteolytic degradation of the myosin heavy chain (MHC) under an inappropriate heating process. Many studies have reported the decrease in MHC in the disintegrated surimi gel but the mechanistic details of this degradation remain unclear. This study employed peptidomic analysis of disintegrated surimi gels from deep-sea bonefish Pterothrissus gissu to reveal the MHC cleavage causing gel disintegration. More peptides derived from an MHC rod were found in the disintegrated P. gissu surimi gels than in the integrated gel. Most MHC peptides were derived from the Src homology 3 domain or near the skip residues. The results of the terminome analysis suggest that the catalytic type of the proteases is responsible for light meromyosin cleavage activated at ∼35 °C. These results showed the temperature-dependent cleavage of the MHC rod, causing disintegration of the P. gissu surimi gel.
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Affiliation(s)
- Yuri Kominami
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Hiroki Nakakubo
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Ryoko Nakamizo
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
- Fish Protein Laboratory, Suzuhiro Kamaboko Honten Co., Ltd., Odawara, Kanagawa 250-0862, Japan
| | - Yoko Matsuoka
- Fish Protein Laboratory, Suzuhiro Kamaboko Honten Co., Ltd., Odawara, Kanagawa 250-0862, Japan
| | - Nobuhiko Ueki
- Fish Protein Laboratory, Suzuhiro Kamaboko Honten Co., Ltd., Odawara, Kanagawa 250-0862, Japan
| | - Jianrong Wan
- Fish Protein Laboratory, Suzuhiro Kamaboko Honten Co., Ltd., Odawara, Kanagawa 250-0862, Japan
| | - Shugo Watabe
- Fish Protein Laboratory, Suzuhiro Kamaboko Honten Co., Ltd., Odawara, Kanagawa 250-0862, Japan
- School of Marine Biosciences, Kitasato University, Sagamihara, Kanagawa 252-0373, Japan
| | - Hideki Ushio
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
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26
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Parker F, Peckham M. Disease mutations in striated muscle myosins. Biophys Rev 2020; 12:887-894. [PMID: 32651905 PMCID: PMC7429545 DOI: 10.1007/s12551-020-00721-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 07/02/2020] [Indexed: 01/23/2023] Open
Abstract
Over 1000 disease-causing missense mutations have been found in human β-cardiac, α-cardiac, embryonic and adult fast myosin 2a myosin heavy chains. Most of these are found in human β-cardiac myosin heavy chain. Mutations in β-cardiac myosin cause hypertrophic cardiomyopathy predominantly, whereas those in α-cardiac are associated with many types of heart disease, of which the most common is dilated cardiomyopathy. Mutations in embryonic and fast myosin 2a affect skeletal muscle function. This review provides a short overview of the mutations in the different myosin isoforms and their disease-causing effects.
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Affiliation(s)
- Francine Parker
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK
| | - Michelle Peckham
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK.
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27
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Daneshparvar N, Taylor DW, O'Leary TS, Rahmani H, Abbasiyeganeh F, Previs MJ, Taylor KA. CryoEM structure of Drosophila flight muscle thick filaments at 7 Å resolution. Life Sci Alliance 2020; 3:3/8/e202000823. [PMID: 32718994 PMCID: PMC7391215 DOI: 10.26508/lsa.202000823] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 06/30/2020] [Accepted: 06/30/2020] [Indexed: 11/24/2022] Open
Abstract
Striated muscle thick filaments are composed of myosin II and several non-myosin proteins. Myosin II's long α-helical coiled-coil tail forms the dense protein backbone of filaments, whereas its N-terminal globular head containing the catalytic and actin-binding activities extends outward from the backbone. Here, we report the structure of thick filaments of the flight muscle of the fruit fly Drosophila melanogaster at 7 Å resolution. Its myosin tails are arranged in curved molecular crystalline layers identical to flight muscles of the giant water bug Lethocerus indicus Four non-myosin densities are observed, three of which correspond to ones found in Lethocerus; one new density, possibly stretchin-mlck, is found on the backbone outer surface. Surprisingly, the myosin heads are disordered rather than ordered along the filament backbone. Our results show striking myosin tail similarity within flight muscle filaments of two insect orders separated by several hundred million years of evolution.
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Affiliation(s)
- Nadia Daneshparvar
- Department of Physics, Florida State University, Tallahassee, FL, USA.,Institute of Molecular Biophysics, Florida State University, Tallahassee, FL, USA
| | - Dianne W Taylor
- Institute of Molecular Biophysics, Florida State University, Tallahassee, FL, USA
| | - Thomas S O'Leary
- Department of Molecular Physiology & Biophysics, University of Vermont College of Medicine, Burlington, VT, USA
| | - Hamidreza Rahmani
- Department of Physics, Florida State University, Tallahassee, FL, USA.,Institute of Molecular Biophysics, Florida State University, Tallahassee, FL, USA
| | | | - Michael J Previs
- Department of Molecular Physiology & Biophysics, University of Vermont College of Medicine, Burlington, VT, USA
| | - Kenneth A Taylor
- Institute of Molecular Biophysics, Florida State University, Tallahassee, FL, USA
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28
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Addressing the Molecular Mechanism of Longitudinal Lamin Assembly Using Chimeric Fusions. Cells 2020; 9:cells9071633. [PMID: 32645958 PMCID: PMC7407374 DOI: 10.3390/cells9071633] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 07/01/2020] [Accepted: 07/02/2020] [Indexed: 12/28/2022] Open
Abstract
The molecular architecture and assembly mechanism of intermediate filaments have been enigmatic for decades. Among those, lamin filaments are of particular interest due to their universal role in cell nucleus and numerous disease-related mutations. Filament assembly is driven by specific interactions of the elementary dimers, which consist of the central coiled-coil rod domain flanked by non-helical head and tail domains. We aimed to investigate the longitudinal 'head-to-tail' interaction of lamin dimers (the so-called ACN interaction), which is crucial for filament assembly. To this end, we prepared a series of recombinant fragments of human lamin A centred around the N- and C-termini of the rod. The fragments were stabilized by fusions to heterologous capping motifs which provide for a correct formation of parallel, in-register coiled-coil dimers. As a result, we established crystal structures of two N-terminal fragments one of which highlights the propensity of the coiled-coil to open up, and one C-terminal rod fragment. Additional studies highlighted the capacity of such N- and C-terminal fragments to form specific complexes in solution, which were further characterized using chemical cross-linking. These data yielded a molecular model of the ACN complex which features a 6.5 nm overlap of the rod ends.
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29
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Kaufmann TL, Schwarz US. Electrostatic and bending energies predict staggering and splaying in nonmuscle myosin II minifilaments. PLoS Comput Biol 2020; 16:e1007801. [PMID: 32628657 PMCID: PMC7365473 DOI: 10.1371/journal.pcbi.1007801] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 07/16/2020] [Accepted: 05/28/2020] [Indexed: 12/11/2022] Open
Abstract
Recent experiments with super-resolution live cell microscopy revealed that nonmuscle myosin II minifilaments are much more dynamic than formerly appreciated, often showing plastic processes such as splitting, concatenation and stacking. Here we combine sequence information, electrostatics and elasticity theory to demonstrate that the parallel staggers at 14.3, 43.2 and 72 nm have a strong tendency to splay their heads away from the minifilament, thus potentially initiating the diverse processes seen in live cells. In contrast, the straight antiparallel stagger with an overlap of 43 nm is very stable and likely initiates minifilament nucleation. Using stochastic dynamics in a newly defined energy landscape, we predict that the optimal parallel staggers between the myosin rods are obtained by a trial-and-error process in which two rods attach and re-attach at different staggers by rolling and zipping motion. The experimentally observed staggers emerge as the configurations with the largest contact times. We find that contact times increase from isoforms C to B to A, that A-B-heterodimers are surprisingly stable and that myosin 18A should incorporate into mixed filaments with a small stagger. Our findings suggest that nonmuscle myosin II minifilaments in the cell are first formed by isoform A and then convert to mixed A-B-filaments, as observed experimentally. Nonmuscle myosin II (NM2) is a non-processive molecular motor that assembles into minifilaments with a typical size of 300 nm to generate force and motion in the actin cytoskeleton. This process is essential for many cellular processes such as adhesion, migration, division and mechanosensing. Due to their small size below the resolution limit, minifilaments are a challenge for imaging with traditional light microscopy. With the advent of super-resolution microscopy, however, it has become apparent that the formation of NM2-minifilaments is much more dynamic than formerly appreciated. Modelling the electrostatic interaction between the rigid rods of the myosin monomers has confirmed the main staggers observed in experiments, but cannot explain these high dynamics. Here we complement electrostatics by elasticity theory and stochastic dynamics to show that the parallel staggers are likely to splay away from the main axis of the minifilament and that monomers attach and detach with rolling and zipping motions. Based on the sequences of the different NM2-isoforms, we predict that isoform A forms the most stable homofilaments and that A-B-heterofilaments are also very stable.
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Affiliation(s)
- Tom L. Kaufmann
- Institute for Theoretical Physics and BioQuant, Heidelberg University, Heidelberg, Germany
| | - Ulrich S. Schwarz
- Institute for Theoretical Physics and BioQuant, Heidelberg University, Heidelberg, Germany
- * E-mail:
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30
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Drennan AC, Krishna S, Seeger MA, Andreas MP, Gardner JM, Sether EKR, Jaspersen SL, Rayment I. Structure and function of Spc42 coiled-coils in yeast centrosome assembly and duplication. Mol Biol Cell 2019; 30:1505-1522. [PMID: 30969903 PMCID: PMC6724696 DOI: 10.1091/mbc.e19-03-0167] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Accepted: 04/05/2019] [Indexed: 11/12/2022] Open
Abstract
Centrosomes and spindle pole bodies (SPBs) are membraneless organelles whose duplication and assembly is necessary for bipolar mitotic spindle formation. The structural organization and functional roles of major proteins in these organelles can provide critical insights into cell division control. Spc42, a phosphoregulated protein with an N-terminal dimeric coiled-coil (DCC), assembles into a hexameric array at the budding yeast SPB core, where it functions as a scaffold for SPB assembly. Here, we present in vitro and in vivo data to elucidate the structural arrangement and biological roles of Spc42 elements. Crystal structures reveal details of two additional coiled-coils in Spc42: a central trimeric coiled-coil and a C-terminal antiparallel DCC. Contributions of the three Spc42 coiled-coils and adjacent undetermined regions to the formation of an ∼145 Å hexameric lattice in an in vitro lipid monolayer assay and to SPB duplication and assembly in vivo reveal structural and functional redundancy in Spc42 assembly. We propose an updated model that incorporates the inherent symmetry of these Spc42 elements into a lattice, and thereby establishes the observed sixfold symmetry. The implications of this model for the organization of the central SPB core layer are discussed.
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Affiliation(s)
- Amanda C. Drennan
- Department of Biochemistry, University of Wisconsin–Madison, WI 53706
| | | | - Mark A. Seeger
- Department of Biochemistry, University of Wisconsin–Madison, WI 53706
| | | | | | | | - Sue L. Jaspersen
- Stowers Institute for Medical Research, Kansas City, MO 64110
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, KS 66160
| | - Ivan Rayment
- Department of Biochemistry, University of Wisconsin–Madison, WI 53706
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31
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Hirve N, Rajanikanth V, Hogan PG, Gudlur A. Coiled-Coil Formation Conveys a STIM1 Signal from ER Lumen to Cytoplasm. Cell Rep 2019; 22:72-83. [PMID: 29298434 DOI: 10.1016/j.celrep.2017.12.030] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Revised: 11/07/2017] [Accepted: 12/10/2017] [Indexed: 10/18/2022] Open
Abstract
STIM1 and STIM2 are endoplasmic reticulum (ER) membrane proteins that sense decreases in ER-luminal free Ca2+ and, through a conformational change in the STIM cytoplasmic domain, control gating of the plasma membrane Ca2+ channel ORAI1. To determine how STIM1 conveys a signal from the ER lumen to the cytoplasm, we studied the Ca2+-dependent conformational change of engineered STIM1 proteins in isolated ER membranes and, in parallel, physiological activation of these proteins in cells. We find that conserved "sentinel" features of the CC1 region help to prevent activation while Ca2+ is bound to STIM ER-luminal domains. Reduced ER-luminal Ca2+ drives a concerted conformational change, in which STIM luminal domains rearrange and the STIM transmembrane helices and initial parts of the CC1 regions pair in an extended coiled coil. This intradimer rearrangement overcomes the relatively weak CC1-SOAR/CAD interactions that hold STIM in an inactive conformation, releasing the SOAR/CAD domain to activate ORAI channels.
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Affiliation(s)
- Nupura Hirve
- Division of Signaling and Gene Expression, La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037, USA
| | - Vangipurapu Rajanikanth
- Division of Signaling and Gene Expression, La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037, USA
| | - Patrick G Hogan
- Division of Signaling and Gene Expression, La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037, USA; Program in Immunology, University of California, San Diego, La Jolla, CA 92037, USA.
| | - Aparna Gudlur
- Division of Signaling and Gene Expression, La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037, USA
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32
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Hershkovitz T, Kurolap A, Ruhrman-Shahar N, Monakier D, DeChene ET, Peretz-Amit G, Funke B, Zucker N, Hirsch R, Tan WH, Baris Feldman H. Clinical diversity of MYH7-related cardiomyopathies: Insights into genotype-phenotype correlations. Am J Med Genet A 2018; 179:365-372. [PMID: 30588760 DOI: 10.1002/ajmg.a.61017] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 11/15/2018] [Accepted: 11/20/2018] [Indexed: 12/21/2022]
Abstract
MYH7-related disease (MRD) is the most common hereditary primary cardiomyopathy (CM), with pathogenic MYH7 variants accounting for approximately 40% of familial hypertrophic CMs. MRDs may also present as skeletal myopathies, with or without CM. Since pathogenic MYH7 variants result in highly variable clinical phenotypes, from mild to fatal forms of cardiac and skeletal myopathies, genotype-phenotype correlations are not always apparent, and translation of the genetic findings to clinical practice can be complicated. Data on genotype-phenotype correlations can help facilitate more specific and personalized decisions on treatment strategies, surveillance, and genetic counseling. We present a series of six MRD pedigrees with rare genotypes, encompassing various clinical presentations and inheritance patterns. This study provides new insights into the spectrum of MRD that is directly translatable to clinical practice.
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Affiliation(s)
- Tova Hershkovitz
- The Genetics Institute, Rambam Health Care Campus, Haifa, Israel
| | - Alina Kurolap
- The Genetics Institute, Rambam Health Care Campus, Haifa, Israel.,Rappaport School of Medicine, Technion - Israel Institute of Technology, Haifa, Israel
| | - Noa Ruhrman-Shahar
- The Raphael Recanati Genetics Institute, Rabin Medical Center, Beilinson Hospital, Petah Tikva, Israel
| | - Daniel Monakier
- Department of Cardiology, Rabin Medical Center, Beilinson Hospital, Petah Tikva and the Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Elizabeth T DeChene
- Division of Genomic Diagnostics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Gabriela Peretz-Amit
- The Raphael Recanati Genetics Institute, Rabin Medical Center, Beilinson Hospital, Petah Tikva, Israel
| | - Birgit Funke
- Department of Pathology, Massachusetts General Hospital, and Harvard Medical School, Boston, Massachusetts
| | - Nili Zucker
- Pediatric Cardiology Unit, Schneider Children's Medical Center, Petah Tikva, Israel
| | - Rafael Hirsch
- Institute of Cardiology, Rabin Medical Center, Beilinson Hospital, Petah Tikva, Israel
| | - Wen-Hann Tan
- Division of Genetics and Genomics, Boston Children's Hospital, and Harvard Medical School, Boston, Massachusetts
| | - Hagit Baris Feldman
- The Genetics Institute, Rambam Health Care Campus, Haifa, Israel.,Rappaport School of Medicine, Technion - Israel Institute of Technology, Haifa, Israel
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33
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Parker F, Batchelor M, Wolny M, Hughes R, Knight PJ, Peckham M. A1603P and K1617del, Mutations in β-Cardiac Myosin Heavy Chain that Cause Laing Early-Onset Distal Myopathy, Affect Secondary Structure and Filament Formation In Vitro and In Vivo. J Mol Biol 2018; 430:1459-1478. [PMID: 29660325 PMCID: PMC5958240 DOI: 10.1016/j.jmb.2018.04.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 03/09/2018] [Accepted: 04/06/2018] [Indexed: 11/04/2022]
Abstract
Over 20 mutations in β-cardiac myosin heavy chain (β-MHC), expressed in cardiac and slow muscle fibers, cause Laing early-onset distal myopathy (MPD-1), a skeletal muscle myopathy. Most of these mutations are in the coiled-coil tail and commonly involve a mutation to a proline or a single-residue deletion, both of which are predicted to strongly affect the secondary structure of the coiled coil. To test this, we characterized the effects of two MPD-1 causing mutations: A1603P and K1617del in vitro and in cells. Both mutations affected secondary structure, decreasing the helical content of 15 heptad and light meromyosin constructs. Both mutations also severely disrupted the ability of glutathione S-transferase–light meromyosin fusion proteins to form minifilaments in vitro, as demonstrated by negative stain electron microscopy. Mutant eGFP-tagged β-MHC accumulated abnormally into the M-line of sarcomeres in cultured skeletal muscle myotubes. Incorporation of eGFP-tagged β-MHC into sarcomeres in adult rat cardiomyocytes was reduced. Molecular dynamics simulations using a composite structure of part of the coiled coil demonstrated that both mutations affected the structure, with the mutation to proline (A1603P) having a smaller effect compared to K1617del. Taken together, it seems likely that the MPD-1 mutations destabilize the coiled coil, resulting in aberrant myosin packing in thick filaments in muscle sarcomeres, providing a potential mechanism for the disease. It is unclear how mutations in the coiled coil of β-myosin heavy chain cause distal myopathy. A1603P and K1617del mutations reduce helicity and affect filament formation in vitro. eGFP-tagged β-myosin heavy chain abnormally accumulates at the M-line of sarcomeres in skeletal myotubes. Molecular dynamics simulations provide a molecular understanding for these experiments. Effects on structure and packing into the thick filament provide a molecular basis for the disease.
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Affiliation(s)
- Francine Parker
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK; Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, UK
| | - Matthew Batchelor
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK; Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, UK
| | - Marcin Wolny
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK; Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, UK
| | - Ruth Hughes
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK; Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, UK
| | - Peter J Knight
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK; Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, UK
| | - Michelle Peckham
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK; Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, UK.
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34
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Singh RR, Dunn JW, Qadan MM, Hall N, Wang KK, Root DD. Whole length myosin binding protein C stabilizes myosin S2 as measured by gravitational force spectroscopy. Arch Biochem Biophys 2017; 638:41-51. [PMID: 29229286 DOI: 10.1016/j.abb.2017.12.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Revised: 11/30/2017] [Accepted: 12/01/2017] [Indexed: 01/21/2023]
Abstract
The mechanical stability of the myosin subfragment-2 (S2) was tested with simulated force spectroscopy (SFS) and gravitational force spectroscopy (GFS). Experiments examined unzipping S2, since it required less force than stretching parallel to the coiled coil. Both GFS and SFS demonstrated that the force required to destabilize the light meromyosin (LMM) was greater than the force required to destabilize the coiled coil at each of three different locations along S2. GFS data also conveyed that the mechanical stability of the S2 region is independent from its association with the myosin thick filament using cofilaments of myosin tail and a single intact myosin. The C-terminal end of myosin binding protein C (MyBPC) binds to LMM and the N-terminal end can bind either S2 or actin. The force required to destabilize the myosin coiled coil molecule was 3 times greater in the presence of MyBPC than in its absence. Furthermore, the in vitro motility assay with full length slow skeletal MyBPC slowed down the actin filament sliding over myosin thick filaments. This study demonstrates that skeletal MyBPC both enhanced the mechanical stability of the S2 coiled coil and reduced the sliding velocity of actin filaments over polymerized myosin filaments.
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Affiliation(s)
- Rohit R Singh
- Department of Biological Sciences, Division of Biochemistry and Molecular Biology, University of North Texas, Denton, TX 76203, USA
| | - James W Dunn
- Department of Biological Sciences, Division of Biochemistry and Molecular Biology, University of North Texas, Denton, TX 76203, USA
| | - Motamed M Qadan
- Department of Biological Sciences, Division of Biochemistry and Molecular Biology, University of North Texas, Denton, TX 76203, USA
| | - Nakiuda Hall
- Department of Biological Sciences, Division of Biochemistry and Molecular Biology, University of North Texas, Denton, TX 76203, USA
| | - Kathy K Wang
- Department of Biological Sciences, Division of Biochemistry and Molecular Biology, University of North Texas, Denton, TX 76203, USA
| | - Douglas D Root
- Department of Biological Sciences, Division of Biochemistry and Molecular Biology, University of North Texas, Denton, TX 76203, USA.
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35
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Hill SE, Nguyen E, Donegan RK, Patterson-Orazem AC, Hazel A, Gumbart JC, Lieberman RL. Structure and Misfolding of the Flexible Tripartite Coiled-Coil Domain of Glaucoma-Associated Myocilin. Structure 2017; 25:1697-1707.e5. [PMID: 29056483 PMCID: PMC5685557 DOI: 10.1016/j.str.2017.09.008] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Revised: 08/07/2017] [Accepted: 09/18/2017] [Indexed: 01/15/2023]
Abstract
Glaucoma-associated myocilin is a member of the olfactomedins, a protein family involved in neuronal development and human diseases. Molecular studies of the myocilin N-terminal coiled coil demonstrate a unique tripartite architecture: a Y-shaped parallel dimer-of-dimers with distinct tetramer and dimer regions. The structure of the dimeric C-terminal 7-heptad repeats elucidates an unexpected repeat pattern involving inter-strand stabilization by oppositely charged residues. Molecular dynamics simulations reveal an alternate accessible conformation in which the terminal inter-strand disulfide limits the extent of unfolding and results in a kinked configuration. By inference, full-length myocilin is also branched, with two pairs of C-terminal olfactomedin domains. Selected variants within the N-terminal region alter the apparent quaternary structure of myocilin but do so without compromising stability or causing aggregation. In addition to increasing our structural knowledge of naturally occurring extracellular coiled coils and biomedically important olfactomedins, this work broadens the scope of protein misfolding in the pathogenesis of myocilin-associated glaucoma.
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Affiliation(s)
- Shannon E Hill
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Elaine Nguyen
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Rebecca K Donegan
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | | | - Anthony Hazel
- School of Physics, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - James C Gumbart
- School of Physics, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Raquel L Lieberman
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA 30332, USA.
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36
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Design considerations in coiled-coil fusion constructs for the structural determination of a problematic region of the human cardiac myosin rod. J Struct Biol 2017; 200:219-228. [PMID: 28743637 DOI: 10.1016/j.jsb.2017.07.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Revised: 06/21/2017] [Accepted: 07/07/2017] [Indexed: 12/23/2022]
Abstract
X-ray structural determination of segments of the myosin rod has proved difficult because of the strong salt-dependent aggregation properties and repeating pattern of charges on the surface of the coiled-coil that lead to the formation of paracrystals. This problem has been resolved in part through the use of globular assembly domains that improve protein folding and prevent aggregation. The primary consideration now in designing coiled-coil fusion constructs for myosin is deciding where to truncate the coiled-coil and which amino acid residues to include from the folding domain. This is especially important for myosin that contains numerous regions of low predicted coiled-coil propensity. Here we describe the strategy adopted to determine the structure of the region that extends from Arg1677 - Leu1797 that included two areas that do not show a strong sequence signature of a conventional left-handed coiled coil or canonical heptad repeat. This demonstrates again that, with careful choice of fusion constructs, overlapping structures exhibit very similar conformations for the myosin rod fragments in the canonical regions. However, conformational variability is seen around Leu1706 which is a hot spot for cardiomyopathy mutations suggesting that this might be important for function.
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37
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Mohanasundaram KA, Grover MP, Crowley TM, Goscinski A, Wouters MA. Mapping genotype-phenotype associations of nsSNPs in coiled-coil oligomerization domains of the human proteome. Hum Mutat 2017; 38:1378-1393. [PMID: 28489284 DOI: 10.1002/humu.23252] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Revised: 04/13/2017] [Accepted: 05/05/2017] [Indexed: 11/11/2022]
Abstract
We assessed the impact of disease mutations (DMs) versus polymorphisms (PYs) in coiled-coil (CC) domains in UniProt by modeling the structural and functional impact of variants in silico with the CC prediction program Multicoil. The structural impact of variants was evaluated with respect to three main metrics: the oligomerization score-to determine whether the variant is stabilizing or destabilizing-the oligomerization state, and the register-specific score. The functional impact was queried indirectly in several ways. First, we examined marginally stable CCs that were either stabilized or destabilized by the variant. Second, we looked for variants that altered the register of the wild-type CC near wild-type irregularities of likely functional importance, such as skips and stammers. Third, we searched for variants that altered the oligomerization state of the CC. DMs tended to be more destabilizing than PYs; but interestingly, PYs were more frequently associated with predicted changes in the oligomerization state. The functional impact was also queried by testing the association of CC variants with multiple phenotypes, that is, pleiotropy. Mutations in CC regions of proteins cause 155 different phenotypes and are more frequently associated with pleiotropy than proteins in general. Importantly, the CC region itself often encodes the pleiotropy.
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Affiliation(s)
| | - Mani P Grover
- School of Medicine, Deakin University, Geelong, Victoria, Australia
| | - Tamsyn M Crowley
- School of Medicine, Deakin University, Geelong, Victoria, Australia.,Australian Animal Health Laboratory, CSIRO Biosecurity Flagship, Geelong, Victoria, Australia
| | - Andrzej Goscinski
- School of Information Technology, Faculty of Science Engineering and Built Environment, Deakin University, Geelong, Victoria, Australia
| | - Merridee A Wouters
- School of Medicine, Deakin University, Geelong, Victoria, Australia.,Olivia Newton-John Cancer Research Institute, Heidelberg, Victoria, Australia.,School of Cancer Medicine, La Trobe University, Bundoora, Victoria, Australia
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38
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Hu Z, Taylor DW, Reedy MK, Edwards RJ, Taylor KA. Structure of myosin filaments from relaxed Lethocerus flight muscle by cryo-EM at 6 Å resolution. SCIENCE ADVANCES 2016; 2:e1600058. [PMID: 27704041 PMCID: PMC5045269 DOI: 10.1126/sciadv.1600058] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Accepted: 08/23/2016] [Indexed: 05/09/2023]
Abstract
We describe a cryo-electron microscopy three-dimensional image reconstruction of relaxed myosin II-containing thick filaments from the flight muscle of the giant water bug Lethocerus indicus. The relaxed thick filament structure is a key element of muscle physiology because it facilitates the reextension process following contraction. Conversely, the myosin heads must disrupt their relaxed arrangement to drive contraction. Previous models predicted that Lethocerus myosin was unique in having an intermolecular head-head interaction, as opposed to the intramolecular head-head interaction observed in all other species. In contrast to the predicted model, we find an intramolecular head-head interaction, which is similar to that of other thick filaments but oriented in a distinctly different way. The arrangement of myosin's long α-helical coiled-coil rod domain has been hypothesized as either curved layers or helical subfilaments. Our reconstruction is the first report having sufficient resolution to track the rod α helices in their native environment at resolutions ~5.5 Å, and it shows that the layer arrangement is correct for Lethocerus. Threading separate paths through the forest of myosin coiled coils are four nonmyosin peptides. We suggest that the unusual position of the heads and the rod arrangement separated by nonmyosin peptides are adaptations for mechanical signal transduction whereby applied tension disrupts the myosin heads as a component of stretch activation.
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Affiliation(s)
- Zhongjun Hu
- Institute of Molecular Biophysics, Florida State University, Tallahassee, FL 32306–4380, USA
| | - Dianne W. Taylor
- Institute of Molecular Biophysics, Florida State University, Tallahassee, FL 32306–4380, USA
| | - Michael K. Reedy
- Department of Cell Biology, Duke University Medical Center, Durham, NC 27607, USA
| | - Robert J. Edwards
- Department of Cell Biology, Duke University Medical Center, Durham, NC 27607, USA
| | - Kenneth A. Taylor
- Institute of Molecular Biophysics, Florida State University, Tallahassee, FL 32306–4380, USA
- Corresponding author.
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39
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An endosomal tether undergoes an entropic collapse to bring vesicles together. Nature 2016; 537:107-111. [PMID: 27556945 PMCID: PMC5142606 DOI: 10.1038/nature19326] [Citation(s) in RCA: 91] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Accepted: 07/19/2016] [Indexed: 12/16/2022]
Abstract
An early step in intracellular transport is the selective recognition of
a vesicle by its appropriate target membrane, a process regulated by Rab GTPases
via the recruitment of tethering effectors1–4. Membrane tethering
confers higher selectivity and efficiency to membrane fusion than the pairing of
SNAREs alone5,6,7. Here, we
addressed the mechanism whereby a tethered vesicle comes closer towards its
target membrane for fusion by reconstituting an endosomal asymmetric tethering
machinery consisting of the dimeric coiled-coil protein EEA16,7
recruited to phosphatidylinositol 3-phosphate membranes and binding vesicles
harboring Rab5. Surprisingly, structural analysis revealed that Rab5:GTP induces
an allosteric conformational change in EEA1, from extended to flexible and
collapsed. Through dynamic analysis by optical tweezers we confirmed that EEA1
captures a vesicle at a distance corresponding to its extended conformation, and
directly measured its flexibility and the forces induced during the tethering
reaction. Expression of engineered EEA1 variants defective in the conformational
change induced prominent clusters of tethered vesicles in vivo.
Our results suggest a new mechanism in which Rab5 induces a change in
flexibility of EEA1, generating an entropic collapse force that
pulls the captured vesicle toward the target membrane to initiate docking and
fusion.
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40
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Guzik-Lendrum S, Rank KC, Bensel BM, Taylor KC, Rayment I, Gilbert SP. Kinesin-2 KIF3AC and KIF3AB Can Drive Long-Range Transport along Microtubules. Biophys J 2016; 109:1472-82. [PMID: 26445448 DOI: 10.1016/j.bpj.2015.08.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Revised: 08/03/2015] [Accepted: 08/04/2015] [Indexed: 12/14/2022] Open
Abstract
Mammalian KIF3AC is classified as a heterotrimeric kinesin-2 that is best known for organelle transport in neurons, yet in vitro studies to characterize its single molecule behavior are lacking. The results presented show that a KIF3AC motor that includes the native helix α7 sequence for coiled-coil formation is highly processive with run lengths of ∼1.23 μm and matching those exhibited by conventional kinesin-1. This result was unexpected because KIF3AC exhibits the canonical kinesin-2 neck-linker sequence that has been reported to be responsible for shorter run lengths observed for another heterotrimeric kinesin-2, KIF3AB. However, KIF3AB with its native neck linker and helix α7 is also highly processive with run lengths of ∼1.62 μm and exceeding those of KIF3AC and kinesin-1. Loop L11, a component of the microtubule-motor interface and implicated in activating ADP release upon microtubule collision, is significantly extended in KIF3C as compared with other kinesins. A KIF3AC encoding a truncation in KIF3C loop L11 (KIF3ACΔL11) exhibited longer run lengths at ∼1.55 μm than wild-type KIF3AC and were more similar to KIF3AB run lengths, suggesting that L11 also contributes to tuning motor processivity. The steady-state ATPase results show that shortening L11 does not alter kcat, consistent with the observation that single molecule velocities are not affected by this truncation. However, shortening loop L11 of KIF3C significantly increases the microtubule affinity of KIF3ACΔL11, revealing another structural and mechanistic property that can modulate processivity. The results presented provide new, to our knowledge, insights to understand structure-function relationships governing processivity and a better understanding of the potential of KIF3AC for long-distance transport in neurons.
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Affiliation(s)
- Stephanie Guzik-Lendrum
- Department of Biological Sciences and Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York
| | - Katherine C Rank
- Department of Biochemistry, University of Wisconsin, Madison, Wisconsin
| | - Brandon M Bensel
- Department of Biological Sciences and Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York
| | - Keenan C Taylor
- Department of Biochemistry, University of Wisconsin, Madison, Wisconsin
| | - Ivan Rayment
- Department of Biochemistry, University of Wisconsin, Madison, Wisconsin.
| | - Susan P Gilbert
- Department of Biological Sciences and Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York.
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41
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Phillips RK, Peter LG, Gilbert SP, Rayment I. Family-specific Kinesin Structures Reveal Neck-linker Length Based on Initiation of the Coiled-coil. J Biol Chem 2016; 291:20372-86. [PMID: 27462072 DOI: 10.1074/jbc.m116.737577] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Indexed: 12/24/2022] Open
Abstract
Kinesin-1, -2, -5, and -7 generate processive hand-over-hand 8-nm steps to transport intracellular cargoes toward the microtubule plus end. This processive motility requires gating mechanisms to coordinate the mechanochemical cycles of the two motor heads to sustain the processive run. A key structural element believed to regulate the degree of processivity is the neck-linker, a short peptide of 12-18 residues, which connects the motor domain to its coiled-coil stalk. Although a shorter neck-linker has been correlated with longer run lengths, the structural data to support this hypothesis have been lacking. To test this hypothesis, seven kinesin structures were determined by x-ray crystallography. Each included the neck-linker motif, followed by helix α7 that constitutes the start of the coiled-coil stalk. In the majority of the structures, the neck-linker length differed from predictions because helix α7, which initiates the coiled-coil, started earlier in the sequence than predicted. A further examination of structures in the Protein Data Bank reveals that there is a great disparity between the predicted and observed starting residues. This suggests that an accurate prediction of the start of a coiled-coil is currently difficult to achieve. These results are significant because they now exclude simple comparisons between members of the kinesin superfamily and add a further layer of complexity when interpreting the results of mutagenesis or protein fusion. They also re-emphasize the need to consider factors beyond the kinesin neck-linker motif when attempting to understand how inter-head communication is tuned to achieve the degree of processivity required for cellular function.
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Affiliation(s)
- Rebecca K Phillips
- From the Department of Biochemistry, University of Wisconsin, Madison, Wisconsin 53706 and
| | - Logan G Peter
- From the Department of Biochemistry, University of Wisconsin, Madison, Wisconsin 53706 and
| | - Susan P Gilbert
- the Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy, New York 12180
| | - Ivan Rayment
- From the Department of Biochemistry, University of Wisconsin, Madison, Wisconsin 53706 and
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42
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Brand P, Dyck PJB, Liu J, Berini S, Selcen D, Milone M. Distal myopathy with coexisting heterozygous TIA1 and MYH7 Variants. Neuromuscul Disord 2016; 26:511-5. [PMID: 27282841 DOI: 10.1016/j.nmd.2016.05.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Revised: 04/28/2016] [Accepted: 05/19/2016] [Indexed: 01/20/2023]
Abstract
TIA1 mutations cause Welander distal myopathy. MYH7 mutations result in various clinical phenotypes, including Laing distal myopathy and cardiomyopathy. We describe a family with coexisting TIA1 and MYH7 variants. The proband is a 67-year-old woman with easy tripping since childhood and progressive asymmetric distal limb weakness, but no cardiac involvement. Muscle biopsy showed rare rimmed vacuoles, minicore-like structures and congophilic inclusions. Her 66-year-old sister has a mild distal myopathy, supraventricular tachycardia and hypertrophic cardiomyopathy. Both sisters carry the only known pathogenic TIA1 mutation and a heterozygous MYH7 variant (c.5459G > A; p.Arg1820Gln). Another sibling with isolated distal myopathy carries only the TIA1 mutation. MYH7 p.Arg1820Gln involves a highly conserved residue and is predicted to be deleterious. Furthermore, the proband's childhood-onset distal leg weakness and sister's cardiomyopathy suggest that MYH7 p.Arg1820Gln likely affects function, favoring a digenic etiology of the myopathy.
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Affiliation(s)
- Patricio Brand
- Department of Neurology, Mayo Clinic, 200 First Street SW, Rochester, Minnesota 55905, USA
| | - P James B Dyck
- Department of Neurology, Mayo Clinic, 200 First Street SW, Rochester, Minnesota 55905, USA
| | - Jie Liu
- PreventionGenetics, 3800 S. Business Park Ave, Marshfield, Wisconsin 54449, USA; Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Sarah Berini
- Department of Neurology, Mayo Clinic, 200 First Street SW, Rochester, Minnesota 55905, USA
| | - Duygu Selcen
- Department of Neurology, Mayo Clinic, 200 First Street SW, Rochester, Minnesota 55905, USA
| | - Margherita Milone
- Department of Neurology, Mayo Clinic, 200 First Street SW, Rochester, Minnesota 55905, USA.
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43
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Qadota H, Mayans O, Matsunaga Y, McMurry JL, Wilson KJ, Kwon GE, Stanford R, Deehan K, Tinley TL, Ngwa VM, Benian GM. The SH3 domain of UNC-89 (obscurin) interacts with paramyosin, a coiled-coil protein, in Caenorhabditis elegans muscle. Mol Biol Cell 2016; 27:1606-20. [PMID: 27009202 PMCID: PMC4865318 DOI: 10.1091/mbc.e15-09-0675] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Revised: 03/16/2016] [Accepted: 03/16/2016] [Indexed: 11/11/2022] Open
Abstract
UNC-89 is a giant polypeptide located at the sarcomeric M-line of Caenorhabditis elegans muscle. The human homologue is obscurin. To understand how UNC-89 is localized and functions, we have been identifying its binding partners. Screening a yeast two-hybrid library revealed that UNC-89 interacts with paramyosin. Paramyosin is an invertebrate-specific coiled-coil dimer protein that is homologous to the rod portion of myosin heavy chains and resides in thick filament cores. Minimally, this interaction requires UNC-89's SH3 domain and residues 294-376 of paramyosin and has a KD of ∼1.1 μM. In unc-89 loss-of-function mutants that lack the SH3 domain, paramyosin is found in accumulations. When the SH3 domain is overexpressed, paramyosin is mislocalized. SH3 domains usually interact with a proline-rich consensus sequence, but the region of paramyosin that interacts with UNC-89's SH3 is α-helical and lacks prolines. Homology modeling of UNC-89's SH3 suggests structural features that might be responsible for this interaction. The SH3-binding region of paramyosin contains a "skip residue," which is likely to locally unwind the coiled-coil and perhaps contributes to the binding specificity.
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Affiliation(s)
- Hiroshi Qadota
- Department of Pathology, Emory University, Atlanta, GA 30322
| | - Olga Mayans
- Department of Biology, University of Konstanz, 78457 Konstanz, Germany
| | - Yohei Matsunaga
- Department of Pathology, Emory University, Atlanta, GA 30322
| | - Jonathan L McMurry
- Department of Molecular and Cellular Biology, Kennesaw State University, Kennesaw, GA 30144
| | - Kristy J Wilson
- Department of Pathology, Emory University, Atlanta, GA 30322
| | - Grace E Kwon
- Department of Pathology, Emory University, Atlanta, GA 30322
| | - Rachel Stanford
- Department of Pathology, Emory University, Atlanta, GA 30322
| | - Kevin Deehan
- Department of Pathology, Emory University, Atlanta, GA 30322
| | - Tina L Tinley
- Department of Pathology, Emory University, Atlanta, GA 30322
| | - Verra M Ngwa
- Department of Molecular and Cellular Biology, Kennesaw State University, Kennesaw, GA 30144
| | - Guy M Benian
- Department of Pathology, Emory University, Atlanta, GA 30322
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Korkmaz EN, Taylor KC, Andreas MP, Ajay G, Heinze NT, Cui Q, Rayment I. A composite approach towards a complete model of the myosin rod. Proteins 2016; 84:172-189. [PMID: 26573747 PMCID: PMC4715562 DOI: 10.1002/prot.24964] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Revised: 10/23/2015] [Accepted: 11/09/2015] [Indexed: 12/17/2022]
Abstract
Sarcomeric myosins have the remarkable ability to form regular bipolar thick filaments that, together with actin thin filaments, constitute the fundamental contractile unit of skeletal and cardiac muscle. This has been established for over 50 years and yet a molecular model for the thick filament has not been attained. In part this is due to the lack of a detailed molecular model for the coiled-coil that constitutes the myosin rod. The ability to self-assemble resides in the C-terminal section of myosin known as light meromyosin (LMM) which exhibits strong salt-dependent aggregation that has inhibited structural studies. Here we evaluate the feasibility of generating a complete model for the myosin rod by combining overlapping structures of five sections of coiled-coil covering 164 amino acid residues which constitute 20% of LMM. Each section contains ∼ 7-9 heptads of myosin. The problem of aggregation was overcome by incorporating the globular folding domains, Gp7 and Xrcc4 which enhance crystallization. The effect of these domains on the stability and conformation of the myosin rod was examined through biophysical studies and overlapping structures. In addition, a computational approach was developed to combine the sections into a contiguous model. The structures were aligned, trimmed to form a contiguous model, and simulated for >700 ns to remove the discontinuities and achieve an equilibrated conformation that represents the native state. This experimental and computational strategy lays the foundation for building a model for the entire myosin rod.
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Affiliation(s)
- E. Nihal Korkmaz
- Department of Chemistry and Theoretical Chemistry Institute, University of Wisconsin, Madison, WI 53706, USA
| | - Keenan C. Taylor
- Department of Biochemistry, University of Wisconsin, 433 Babcock Drive, Madison, WI 53706, USA
| | - Michael P. Andreas
- Department of Biochemistry, University of Wisconsin, 433 Babcock Drive, Madison, WI 53706, USA
| | - Guatam Ajay
- Department of Biochemistry, University of Wisconsin, 433 Babcock Drive, Madison, WI 53706, USA
| | - Nathan T. Heinze
- Department of Biochemistry, University of Wisconsin, 433 Babcock Drive, Madison, WI 53706, USA
| | - Qiang Cui
- Department of Chemistry and Theoretical Chemistry Institute, University of Wisconsin, Madison, WI 53706, USA
| | - Ivan Rayment
- Department of Biochemistry, University of Wisconsin, 433 Babcock Drive, Madison, WI 53706, USA
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