1
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Hojjatian A, Taylor DW, Daneshparvar N, Fagnant PM, Trybus KM, Taylor KA. Double-headed binding of myosin II to F-actin shows the effect of strain on head structure. J Struct Biol 2023; 215:107995. [PMID: 37414375 PMCID: PMC10544818 DOI: 10.1016/j.jsb.2023.107995] [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: 04/04/2022] [Revised: 06/25/2023] [Accepted: 07/03/2023] [Indexed: 07/08/2023]
Abstract
Force production in muscle is achieved through the interaction of myosin and actin. Strong binding states in active muscle are associated with Mg·ADP bound to the active site; release of Mg·ADP allows rebinding of ATP and dissociation from actin. Thus, Mg·ADP binding is positioned for adaptation as a force sensor. Mechanical loads on the lever arm can affect the ability of myosin to release Mg·ADP but exactly how this is done is poorly defined. Here we use F-actin decorated with double-headed smooth muscle myosin fragments in the presence of Mg·ADP to visualize the effect of internally supplied tension on the paired lever arms using cryoEM. The interaction of the paired heads with two adjacent actin subunits is predicted to place one lever arm under positive and the other under negative strain. The converter domain is believed to be the most flexible domain within myosin head. Our results, instead, point to the segment of heavy chain between the essential and regulatory light chains as the location of the largest structural change. Moreover, our results suggest no large changes in the myosin coiled coil tail as the locus of strain relief when both heads bind F-actin. The method would be adaptable to double-headed members of the myosin family. We anticipate that the study of actin-myosin interaction using double-headed fragments enables visualization of domains that are typically noisy in decoration with single-headed fragments.
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Affiliation(s)
- Alimohammad Hojjatian
- Inst. of Molecular Biophysics, Florida State University, Tallahassee, FL 32306, United States
| | - Dianne W Taylor
- Inst. of Molecular Biophysics, Florida State University, Tallahassee, FL 32306, United States
| | - Nadia Daneshparvar
- Inst. of Molecular Biophysics, Florida State University, Tallahassee, FL 32306, United States
| | - Patricia M Fagnant
- Dept of Molecular Physiology & Biophysics, University of Vermont College of Medicine, Burlington, VT 05405, United States
| | - Kathleen M Trybus
- Dept of Molecular Physiology & Biophysics, University of Vermont College of Medicine, Burlington, VT 05405, United States
| | - Kenneth A Taylor
- Inst. of Molecular Biophysics, Florida State University, Tallahassee, FL 32306, United States.
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2
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Yampolskaya DS, Kopylova GV, Shchepkin DV, Bershitsky SY, Matyushenko AM, Levitsky DI. Properties of Cardiac Myosin with Cardiomyopathic Mutations in Essential Light Chains. BIOCHEMISTRY. BIOKHIMIIA 2022; 87:1260-1267. [PMID: 36509720 DOI: 10.1134/s0006297922110050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The effects of cardiomyopathic mutations E56G, M149V, and E177G in the MYL3 gene encoding essential light chain of human ventricular myosin (ELCv), on the functional properties of cardiac myosin and its isolated head (myosin subfragment 1, S1) were investigated. Only the M149V mutation upregulated the actin-activated ATPase activity of S1. All mutations significantly increased the Ca2+-sensitivity of the sliding velocity of thin filaments on the surface with immobilized myosin in the in vitro motility assay, while mutations E56G and M149V (but not E177G) reduced the sliding velocity of regulated thin filaments and F-actin filaments almost twice. Therefore, despite the fact that all studied mutations in ELCv are involved in the development of hypertrophic cardiomyopathy, the mechanisms of their influence on the actin-myosin interaction are different.
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Affiliation(s)
- Daria S Yampolskaya
- Bach Institute of Biochemistry, Biotechnology Research Center, Russian Academy of Sciences, Moscow, 119071, Russia
| | - Galina V Kopylova
- Institute of Immunology and Physiology, Ural Branch of the Russian Academy of Sciences, Yekaterinburg, 620049, Russia
| | - Daniil V Shchepkin
- Institute of Immunology and Physiology, Ural Branch of the Russian Academy of Sciences, Yekaterinburg, 620049, Russia
| | - Sergey Y Bershitsky
- Institute of Immunology and Physiology, Ural Branch of the Russian Academy of Sciences, Yekaterinburg, 620049, Russia
| | - Alexander M Matyushenko
- Bach Institute of Biochemistry, Biotechnology Research Center, Russian Academy of Sciences, Moscow, 119071, Russia
| | - Dmitrii I Levitsky
- Bach Institute of Biochemistry, Biotechnology Research Center, Russian Academy of Sciences, Moscow, 119071, Russia.
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3
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Morck MM, Bhowmik D, Pathak D, Dawood A, Spudich J, Ruppel KM. Hypertrophic cardiomyopathy mutations in the pliant and light chain-binding regions of the lever arm of human β-cardiac myosin have divergent effects on myosin function. eLife 2022; 11:e76805. [PMID: 35767336 PMCID: PMC9242648 DOI: 10.7554/elife.76805] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Accepted: 06/12/2022] [Indexed: 11/13/2022] Open
Abstract
Mutations in the lever arm of β-cardiac myosin are a frequent cause of hypertrophic cardiomyopathy, a disease characterized by hypercontractility and eventual hypertrophy of the left ventricle. Here, we studied five such mutations: three in the pliant region of the lever arm (D778V, L781P, and S782N) and two in the light chain-binding region (A797T and F834L). We investigated their effects on both motor function and myosin subfragment 2 (S2) tail-based autoinhibition. The pliant region mutations had varying effects on the motor function of a myosin construct lacking the S2 tail: overall, D778V increased power output, L781P reduced power output, and S782N had little effect on power output, while all three reduced the external force sensitivity of the actin detachment rate. With a myosin containing the motor domain and the proximal S2 tail, the pliant region mutations also attenuated autoinhibition in the presence of filamentous actin but had no impact in the absence of actin. By contrast, the light chain-binding region mutations had little effect on motor activity but produced marked reductions in autoinhibition in both the presence and absence of actin. Thus, mutations in the lever arm of β-cardiac myosin have divergent allosteric effects on myosin function, depending on whether they are in the pliant or light chain-binding regions.
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Affiliation(s)
- Makenna M Morck
- Stanford Cardiovascular Institute, Stanford University School of MedicineStanfordUnited States
- Department of Biochemistry, Stanford University School of MedicineStanfordUnited States
| | - Debanjan Bhowmik
- Stanford Cardiovascular Institute, Stanford University School of MedicineStanfordUnited States
- Department of Biochemistry, Stanford University School of MedicineStanfordUnited States
| | - Divya Pathak
- Stanford Cardiovascular Institute, Stanford University School of MedicineStanfordUnited States
- Department of Biochemistry, Stanford University School of MedicineStanfordUnited States
| | - Aminah Dawood
- Stanford Cardiovascular Institute, Stanford University School of MedicineStanfordUnited States
- Department of Biochemistry, Stanford University School of MedicineStanfordUnited States
| | - James Spudich
- Stanford Cardiovascular Institute, Stanford University School of MedicineStanfordUnited States
- Department of Biochemistry, Stanford University School of MedicineStanfordUnited States
| | - Kathleen M Ruppel
- Stanford Cardiovascular Institute, Stanford University School of MedicineStanfordUnited States
- Department of Biochemistry, Stanford University School of MedicineStanfordUnited States
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4
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Caremani M, Reconditi M. Anisotropic Elasticity of the Myosin Motor in Muscle. Int J Mol Sci 2022; 23:ijms23052566. [PMID: 35269709 PMCID: PMC8909946 DOI: 10.3390/ijms23052566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 02/08/2022] [Accepted: 02/23/2022] [Indexed: 11/16/2022] Open
Abstract
To define the mechanics and energetics of the myosin motor action in muscles, it is mandatory to know fundamental parameters such as the stiffness and the force of the single myosin motor, and the fraction of motors attached during contraction. These parameters can be defined in situ using sarcomere-level mechanics in single muscle fibers under the assumption that the stiffness of a myosin dimer with both motors attached (as occurs in rigor, when all motors are attached) is twice that of a single motor (as occurs in the isometric contraction). We use a mechanical/structural model to identify the constraints that underpin the stiffness of the myosin dimer with both motors attached to actin. By comparing the results of the model with the data in the literature, we conclude that the two-fold axial stiffness of the dimers with both motors attached is justified by a stiffness of the myosin motor that is anisotropic and higher along the axis of the myofilaments. A lower azimuthal stiffness of the motor plays an important role in the complex architecture of the sarcomere by allowing the motors to attach to actin filaments at different azimuthal angles relative to the thick filament.
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Affiliation(s)
- Marco Caremani
- PhysioLab, Università di Firenze, 50019 Sesto Fiorentino, Italy;
- Dipartimento di Biologia, Università di Firenze, 50019 Sesto Fiorentino, Italy
| | - Massimo Reconditi
- PhysioLab, Università di Firenze, 50019 Sesto Fiorentino, Italy;
- Dipartimento di Medicina Sperimentale e Clinica, Università di Firenze, 50134 Firenze, Italy
- Correspondence: ; Tel.: +39-055-457-4714
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5
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Zhang N, Zhou S, Ji HH, Li XD. Effects of the IQ1 motif of Drosophila myosin-5 on the calcium interaction of calmodulin. Cell Calcium 2022; 103:102549. [DOI: 10.1016/j.ceca.2022.102549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 01/24/2022] [Accepted: 02/02/2022] [Indexed: 11/26/2022]
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6
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Le Clec’h W, Chevalier FD, McDew-White M, Menon V, Arya GA, Anderson TJ. Genetic architecture of transmission stage production and virulence in schistosome parasites. Virulence 2021; 12:1508-1526. [PMID: 34167443 PMCID: PMC8237990 DOI: 10.1080/21505594.2021.1932183] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 05/06/2021] [Accepted: 05/14/2021] [Indexed: 12/30/2022] Open
Abstract
Both theory and experimental data from pathogens suggest that the production of transmission stages should be strongly associated with virulence, but the genetic bases of parasite transmission/virulence traits are poorly understood. The blood fluke Schistosoma mansoni shows extensive variation in numbers of cercariae larvae shed and in their virulence to infected snail hosts, consistent with expected trade-offs between parasite transmission and virulence. We crossed schistosomes from two populations that differ 8-fold in cercarial shedding and in their virulence to Biomphalaria glabrata snail hosts, and determined four-week cercarial shedding profiles in F0 parents, F1 parents and 376 F2 progeny from two independent crosses in inbred snails. Sequencing and linkage analysis revealed that cercarial production is polygenic and controlled by five QTLs (i.e. Quantitative Trait Loci). These QTLs act additively, explaining 28.56% of the phenotypic variation. These results demonstrate that the genetic architecture of key traits relevant to schistosome ecology can be dissected using classical linkage mapping approaches.
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Affiliation(s)
- Winka Le Clec’h
- Texas Biomedical Research Institute, San Antonio, Texas, USA
| | | | | | - Vinay Menon
- Texas Biomedical Research Institute, San Antonio, Texas, USA
| | - Grace-Ann Arya
- Texas Biomedical Research Institute, San Antonio, Texas, USA
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7
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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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8
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Panchal K, Tiwari AK. Miro (Mitochondrial Rho GTPase), a key player of mitochondrial axonal transport and mitochondrial dynamics in neurodegenerative diseases. Mitochondrion 2020; 56:118-135. [PMID: 33127590 DOI: 10.1016/j.mito.2020.10.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 10/14/2020] [Accepted: 10/19/2020] [Indexed: 02/07/2023]
Abstract
Miro (mitochondrial Rho GTPases) a mitochondrial outer membrane protein, plays a vital role in the microtubule-based mitochondrial axonal transport, mitochondrial dynamics (fusion and fission) and Mito-Ca2+ homeostasis. It forms a major protein complex with Milton (an adaptor protein), kinesin and dynein (motor proteins), and facilitates bidirectional mitochondrial axonal transport such as anterograde and retrograde transport. By forming this protein complex, Miro facilitates the mitochondrial axonal transport and fulfills the neuronal energy demand, maintain the mitochondrial homeostasis and neuronal survival. It has been demonstrated that altered mitochondrial biogenesis, improper mitochondrial axonal transport, and mitochondrial dynamics are the early pathologies associated with most of the neurodegenerative diseases (NDs). Being the sole mitochondrial outer membrane protein associated with mitochondrial axonal transport-related processes, Miro proteins can be one of the key players in various NDs such as Alzheimer's disease (AD), Parkinson's disease (PD), Amyotrophic lateral sclerosis (ALS) and Huntington's disease (HD). Thus, in the current review, we have discussed the evolutionarily conserved Miro proteins and its role in the pathogenesis of the various NDs. From this, we indicated that Miro proteins may act as a potential target for a novel therapeutic intervention for the treatment of various NDs.
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Affiliation(s)
- Komal Panchal
- Genetics & Developmental Biology Laboratory, Department of Biological Sciences & Biotechnology, Institute of Advanced Research (IAR), Koba, Gandhinagar, Gujarat 382426, India
| | - Anand Krishna Tiwari
- Genetics & Developmental Biology Laboratory, Department of Biological Sciences & Biotechnology, Institute of Advanced Research (IAR), Koba, Gandhinagar, Gujarat 382426, India.
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9
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Moussaoui D, Robblee JP, Auguin D, Krementsova EB, Haase S, Blake TCA, Baum J, Robert-Paganin J, Trybus KM, Houdusse A. Full-length Plasmodium falciparum myosin A and essential light chain PfELC structures provide new anti-malarial targets. eLife 2020; 9:e60581. [PMID: 33046215 PMCID: PMC7553781 DOI: 10.7554/elife.60581] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 09/17/2020] [Indexed: 12/22/2022] Open
Abstract
Parasites from the genus Plasmodium are the causative agents of malaria. The mobility, infectivity, and ultimately pathogenesis of Plasmodium falciparum rely on a macromolecular complex, called the glideosome. At the core of the glideosome is an essential and divergent Myosin A motor (PfMyoA), a first order drug target against malaria. Here, we present the full-length structure of PfMyoA in two states of its motor cycle. We report novel interactions that are essential for motor priming and the mode of recognition of its two light chains (PfELC and MTIP) by two degenerate IQ motifs. Kinetic and motility assays using PfMyoA variants, along with molecular dynamics, demonstrate how specific priming and atypical sequence adaptations tune the motor's mechano-chemical properties. Supported by evidence for an essential role of the PfELC in malaria pathogenesis, these structures provide a blueprint for the design of future anti-malarials targeting both the glideosome motor and its regulatory elements.
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Affiliation(s)
- Dihia Moussaoui
- Structural Motility, Institut Curie, Paris Université Sciences et Lettres, Sorbonne Université, CNRS UMR144ParisFrance
| | - James P Robblee
- Department of Molecular Physiology and Biophysics, University of VermontBurlingtonUnited States
| | - Daniel Auguin
- Laboratoire de Biologie des Ligneux et des Grandes Cultures (LBLGC), Université d’Orléans, INRAE, USC1328OrléansFrance
| | - Elena B Krementsova
- Department of Molecular Physiology and Biophysics, University of VermontBurlingtonUnited States
| | - Silvia Haase
- Department of Life Sciences, Imperial College London, South KensingtonLondonUnited Kingdom
| | - Thomas CA Blake
- Department of Life Sciences, Imperial College London, South KensingtonLondonUnited Kingdom
| | - Jake Baum
- Department of Life Sciences, Imperial College London, South KensingtonLondonUnited Kingdom
| | - Julien Robert-Paganin
- Structural Motility, Institut Curie, Paris Université Sciences et Lettres, Sorbonne Université, CNRS UMR144ParisFrance
| | - Kathleen M Trybus
- Department of Molecular Physiology and Biophysics, University of VermontBurlingtonUnited States
| | - Anne Houdusse
- Structural Motility, Institut Curie, Paris Université Sciences et Lettres, Sorbonne Université, CNRS UMR144ParisFrance
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10
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Costa AR, Sousa MM. Non-Muscle Myosin II in Axonal Cell Biology: From the Growth Cone to the Axon Initial Segment. Cells 2020; 9:cells9091961. [PMID: 32858875 PMCID: PMC7563147 DOI: 10.3390/cells9091961] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 08/21/2020] [Accepted: 08/21/2020] [Indexed: 12/14/2022] Open
Abstract
By binding to actin filaments, non-muscle myosin II (NMII) generates actomyosin networks that hold unique contractile properties. Their dynamic nature is essential for neuronal biology including the establishment of polarity, growth cone formation and motility, axon growth during development (and axon regeneration in the adult), radial and longitudinal axonal tension, and synapse formation and function. In this review, we discuss the current knowledge on the spatial distribution and function of the actomyosin cytoskeleton in different axonal compartments. We highlight some of the apparent contradictions and open questions in the field, including the role of NMII in the regulation of axon growth and regeneration, the possibility that NMII structural arrangement along the axon shaft may control both radial and longitudinal contractility, and the mechanism and functional purpose underlying NMII enrichment in the axon initial segment. With the advances in live cell imaging and super resolution microscopy, it is expected that in the near future the spatial distribution of NMII in the axon, and the mechanisms by which it participates in axonal biology will be further untangled.
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11
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Robert-Paganin J, Pylypenko O, Kikuti C, Sweeney HL, Houdusse A. Force Generation by Myosin Motors: A Structural Perspective. Chem Rev 2019; 120:5-35. [PMID: 31689091 DOI: 10.1021/acs.chemrev.9b00264] [Citation(s) in RCA: 71] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Generating force and movement is essential for the functions of cells and organisms. A variety of molecular motors that can move on tracks within cells have evolved to serve this role. How these motors interact with their tracks and how that, in turn, leads to the generation of force and movement is key to understanding the cellular roles that these motor-track systems serve. This review is focused on the best understood of these systems, which is the molecular motor myosin that moves on tracks of filamentous (F-) actin. The review highlights both the progress and the limits of our current understanding of how force generation can be controlled by F-actin-myosin interactions. What has emerged are insights they may serve as a framework for understanding the design principles of a number of types of molecular motors and their interactions with their tracks.
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Affiliation(s)
- Julien Robert-Paganin
- Structural Motility , UMR 144 CNRS/Curie Institute , 26 rue d'ulm , 75258 Paris cedex 05 , France
| | - Olena Pylypenko
- Structural Motility , UMR 144 CNRS/Curie Institute , 26 rue d'ulm , 75258 Paris cedex 05 , France
| | - Carlos Kikuti
- Structural Motility , UMR 144 CNRS/Curie Institute , 26 rue d'ulm , 75258 Paris cedex 05 , France
| | - H Lee Sweeney
- Department of Pharmacology & Therapeutics and the Myology Institute , University of Florida College of Medicine , PO Box 100267, Gainesville , Florida 32610-0267 , United States
| | - Anne Houdusse
- Structural Motility , UMR 144 CNRS/Curie Institute , 26 rue d'ulm , 75258 Paris cedex 05 , France
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12
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Yang S, Lee KH, Woodhead JL, Sato O, Ikebe M, Craig R. The central role of the tail in switching off 10S myosin II activity. J Gen Physiol 2019; 151:1081-1093. [PMID: 31387899 PMCID: PMC6719407 DOI: 10.1085/jgp.201912431] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Accepted: 07/08/2019] [Indexed: 01/06/2023] Open
Abstract
Myosin II is a motor protein with two heads and an extended tail that plays an essential role in cell motility. Its active form is a polymer (myosin filament) that pulls on actin to generate motion. Its inactive form is a monomer with a compact structure (10S sedimentation coefficient), in which the tail is folded and the two heads interact with each other, inhibiting activity. This conformation is thought to function in cells as an energy-conserving form of the molecule suitable for storage as well as transport to sites of filament assembly. The mechanism of inhibition of the compact molecule is not fully understood. We have performed a 3-D reconstruction of negatively stained 10S myosin from smooth muscle in the inhibited state using single-particle analysis. The reconstruction reveals multiple interactions between the tail and the two heads that appear to trap ATP hydrolysis products, block actin binding, hinder head phosphorylation, and prevent filament formation. Blocking these essential features of myosin function could explain the high degree of inhibition of the folded form of myosin thought to underlie its energy-conserving function in cells. The reconstruction also suggests a mechanism for unfolding when myosin is activated by phosphorylation.
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Affiliation(s)
- Shixin Yang
- Division of Cell Biology and Imaging, Department of Radiology, University of Massachusetts Medical School, Worcester, MA
| | - Kyoung Hwan Lee
- Division of Cell Biology and Imaging, Department of Radiology, University of Massachusetts Medical School, Worcester, MA
| | - John L Woodhead
- Division of Cell Biology and Imaging, Department of Radiology, University of Massachusetts Medical School, Worcester, MA
| | - Osamu Sato
- Department of Cellular and Molecular Biology, University of Texas Health Science Center at Tyler, Tyler, TX
| | - Mitsuo Ikebe
- Department of Cellular and Molecular Biology, University of Texas Health Science Center at Tyler, Tyler, TX
| | - Roger Craig
- Division of Cell Biology and Imaging, Department of Radiology, University of Massachusetts Medical School, Worcester, MA
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13
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Yadav S, Sitbon YH, Kazmierczak K, Szczesna-Cordary D. Hereditary heart disease: pathophysiology, clinical presentation, and animal models of HCM, RCM, and DCM associated with mutations in cardiac myosin light chains. Pflugers Arch 2019; 471:683-699. [PMID: 30706179 DOI: 10.1007/s00424-019-02257-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 12/26/2018] [Accepted: 01/13/2019] [Indexed: 02/07/2023]
Abstract
Genetic cardiomyopathies, a group of cardiovascular disorders based on ventricular morphology and function, are among the leading causes of morbidity and mortality worldwide. Such genetically driven forms of hypertrophic (HCM), dilated (DCM), and restrictive (RCM) cardiomyopathies are chronic, debilitating diseases that result from biomechanical defects in cardiac muscle contraction and frequently progress to heart failure (HF). Locus and allelic heterogeneity, as well as clinical variability combined with genetic and phenotypic overlap between different cardiomyopathies, have challenged proper clinical prognosis and provided an incentive for identification of pathogenic variants. This review attempts to provide an overview of inherited cardiomyopathies with a focus on their genetic etiology in myosin regulatory (RLC) and essential (ELC) light chains, which are EF-hand protein family members with important structural and regulatory roles. From the clinical discovery of cardiomyopathy-linked light chain mutations in patients to an array of exploratory studies in animals, and reconstituted and recombinant systems, we have summarized the current state of knowledge on light chain mutations and how they induce physiological disease states via biochemical and biomechanical alterations at the molecular, tissue, and organ levels. Cardiac myosin RLC phosphorylation and the N-terminus ELC have been discussed as two important emerging modalities with important implications in the regulation of myosin motor function, and thus cardiac performance. A comprehensive understanding of such triggers is absolutely necessary for the development of target-specific rescue strategies to ameliorate or reverse the effects of myosin light chain-related inherited cardiomyopathies.
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MESH Headings
- Animals
- Cardiomyopathy, Dilated/etiology
- Cardiomyopathy, Dilated/genetics
- Cardiomyopathy, Dilated/pathology
- Cardiomyopathy, Hypertrophic/etiology
- Cardiomyopathy, Hypertrophic/genetics
- Cardiomyopathy, Hypertrophic/pathology
- Cardiomyopathy, Restrictive/etiology
- Cardiomyopathy, Restrictive/genetics
- Cardiomyopathy, Restrictive/pathology
- Disease Models, Animal
- Humans
- Mutation
- Myosin Light Chains/genetics
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Affiliation(s)
- Sunil Yadav
- Department of Molecular and Cellular Pharmacology, University of Miami Miller School of Medicine, 1600 NW 10th Ave., Miami, FL, 33136, USA
| | - Yoel H Sitbon
- 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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14
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Logvinova DS, Levitsky DI. Essential Light Chains of Myosin and Their Role in Functioning of the Myosin Motor. BIOCHEMISTRY (MOSCOW) 2018; 83:944-960. [DOI: 10.1134/s0006297918080060] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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15
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Understanding Miro GTPases: Implications in the Treatment of Neurodegenerative Disorders. Mol Neurobiol 2018; 55:7352-7365. [PMID: 29411264 PMCID: PMC6096957 DOI: 10.1007/s12035-018-0927-x] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Accepted: 01/24/2018] [Indexed: 12/19/2022]
Abstract
The Miro GTPases represent an unusual subgroup of the Ras superfamily and have recently emerged as important mediators of mitochondrial dynamics and for maintaining neuronal health. It is now well-established that these enzymes act as essential components of a Ca2+-sensitive motor complex, facilitating the transport of mitochondria along microtubules in several cell types, including dopaminergic neurons. The Miros appear to be critical for both anterograde and retrograde mitochondrial transport in axons and dendrites, both of which are considered essential for neuronal health. Furthermore, the Miros may be significantly involved in the development of several serious pathological processes, including the development of neurodegenerative and psychiatric disorders. In this review, we discuss the molecular structure and known mitochondrial functions of the Miro GTPases in humans and other organisms, in the context of neurodegenerative disease. Finally, we consider the potential human Miros hold as novel therapeutic targets for the treatment of such disease.
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16
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Kawasaki H, Kretsinger RH. Structural and functional diversity of EF-hand proteins: Evolutionary perspectives. Protein Sci 2017; 26:1898-1920. [PMID: 28707401 PMCID: PMC5606533 DOI: 10.1002/pro.3233] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Revised: 07/07/2017] [Accepted: 07/07/2017] [Indexed: 01/02/2023]
Abstract
We have classified 865 sequences of EF-hand proteins from five proteomes into 156 subfamilies. These subfamilies were put into six groups. Evolutionary relationships among subfamilies and groups were analyzed from the inferred ancestral sequence for each subfamily. CTER, CPV, and PEF groups arose from a common EF-lobe (pair of adjacent EF-hands). They have two or more EF-lobes; the relative positions of their EF-lobes differ from each other. Comparisons of the ancestral sequences and the inferred structures of the EF-lobes of these groups indicate that the mutual positions of EF-lobes were established soon after divergence of an EF-lobe for each group and before the duplication and fusion of EF-lobe gene(s). These ancestral sequences reveal that some subfamilies in low similarity and isolated groups did not evolve from the EF-lobe precursor, even if their conformations are similar to the canonical EF-hand. This is an example of convergent evolution.
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Affiliation(s)
- Hiroshi Kawasaki
- Department of Medical Life ScienceGraduate School of Medical Life Science, Yokohama City UniversityYokohamaKanagawa230‐0045Japan
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17
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Powell CJ, Jenkins ML, Parker ML, Ramaswamy R, Kelsen A, Warshaw DM, Ward GE, Burke JE, Boulanger MJ. Dissecting the molecular assembly of the Toxoplasma gondii MyoA motility complex. J Biol Chem 2017; 292:19469-19477. [PMID: 28972141 DOI: 10.1074/jbc.m117.809632] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Revised: 09/22/2017] [Indexed: 01/28/2023] Open
Abstract
Apicomplexan parasites such as Toxoplasma gondii rely on a unique form of locomotion known as gliding motility. Generating the mechanical forces to support motility are divergent class XIV myosins (MyoA) coordinated by accessory proteins known as light chains. Although the importance of the MyoA-light chain complex is well-established, the detailed mechanisms governing its assembly and regulation are relatively unknown. To establish a molecular blueprint of this dynamic complex, we first mapped the adjacent binding sites of light chains MLC1 and ELC1 on the MyoA neck (residues 775-818) using a combination of hydrogen-deuterium exchange mass spectrometry and isothermal titration calorimetry. We then determined the 1.85 Å resolution crystal structure of MLC1 in complex with its cognate MyoA peptide. Structural analysis revealed a bilobed architecture with MLC1 clamping tightly around the helical MyoA peptide, consistent with the stable 10 nm Kd measured by isothermal titration calorimetry. We next showed that coordination of calcium by an EF-hand in ELC1 and prebinding of MLC1 to the MyoA neck enhanced the affinity of ELC1 for the MyoA neck 7- and 8-fold, respectively. When combined, these factors enhanced ELC1 binding 49-fold (to a Kd of 12 nm). Using the full-length MyoA motor (residues 1-831), we then showed that, in addition to coordinating the neck region, ELC1 appears to engage the MyoA converter subdomain, which couples the motor domain to the neck. These data support an assembly model where staged binding events cooperate to yield high-affinity complexes that are able to maximize force transduction.
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Affiliation(s)
- Cameron J Powell
- From the Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8P 5C2, Canada and
| | - Meredith L Jenkins
- From the Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8P 5C2, Canada and
| | - Michelle L Parker
- From the Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8P 5C2, Canada and
| | - Raghavendran Ramaswamy
- From the Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8P 5C2, Canada and
| | - Anne Kelsen
- the Departments of Microbiology and Molecular Genetics and
| | - David M Warshaw
- Molecular Physiology and Biophysics, University of Vermont, Burlington, Vermont 05405
| | - Gary E Ward
- the Departments of Microbiology and Molecular Genetics and
| | - John E Burke
- From the Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8P 5C2, Canada and
| | - Martin J Boulanger
- From the Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8P 5C2, Canada and
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18
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Guhathakurta P, Prochniewicz E, Roopnarine O, Rohde JA, Thomas DD. A Cardiomyopathy Mutation in the Myosin Essential Light Chain Alters Actomyosin Structure. Biophys J 2017; 113:91-100. [PMID: 28700929 DOI: 10.1016/j.bpj.2017.05.027] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Revised: 05/16/2017] [Accepted: 05/17/2017] [Indexed: 01/01/2023] Open
Abstract
We have used site-directed time-resolved fluorescence resonance energy transfer to determine the effect of a pathological mutation in the human ventricular essential light chain (hVELC) of myosin, on the structural dynamics of the actin-myosin complex. The hVELC modulates the function of actomyosin, through the interaction of its N-terminal extension with actin and its C-terminal lobe with the myosin heavy chain. Several mutations in hVELC are associated with hypertrophic cardiomyopathy (HCM). Some biochemical effects of these mutations are known, but further insight is needed about their effects on the structural dynamics of functioning actomyosin. Therefore, we introduced the HCM mutation E56G into a single-cysteine (C16) hVELC construct and substituted it for the VELC of bovine cardiac myosin subfragment 1. Using a donor fluorescent probe on actin (at C374) and an acceptor probe on C16 of hVELC, we performed time-resolved fluorescence resonance energy transfer, directly detecting structural changes within the bound actomyosin complex during function. The E56G mutation has no significant effect on actin-activated ATPase activity or actomyosin affinity in the presence of ATP, or on the structure of the strong-binding S complex in the absence of ATP. However, in the presence of saturating ATP, where both W (prepowerstroke) and S (postpowerstroke) structural states are observed, the mutant increases the mole fraction of the S complex (increasing the duty ratio), while shifting the structure of the remaining W complex toward that of S, indicating a structural redistribution toward the strongly bound (force-generating) complex. We propose that this effect is responsible for the hypercontractile phenotype induced by this HCM mutation in myosin.
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Affiliation(s)
- Piyali Guhathakurta
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota
| | - Ewa Prochniewicz
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota
| | - Osha Roopnarine
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota
| | - John A Rohde
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota
| | - David D Thomas
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota.
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19
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Liao J, Deng J, Qin Z, Tang J, Shu M, Ding C, Liu J, Hu C, Yuan M, Huang Y, Yang R, Zhou Y. Genome-Wide Identification and Analyses of Calmodulins and Calmodulin-like Proteins in Lotus japonicas. FRONTIERS IN PLANT SCIENCE 2017; 8:482. [PMID: 28424729 PMCID: PMC5380670 DOI: 10.3389/fpls.2017.00482] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Accepted: 03/20/2017] [Indexed: 05/10/2023]
Abstract
L. japonicus, a model plant of legumes plants, is widely used in symbiotic nitrogen fixation. A large number of studies on it have been published based on the genetic, biochemical, structural studies. These results are secondhand reports that CaM is a key regulator during Rhizobial infection. In plants, there are multiple CaM genes encoding several CaM isoforms with only minor amino acid differences. Moreover, the regulation mechanism of this family of proteins during rhizobia infection is still unclear. In the current study, a family of genes encoding CaMs and CMLs that possess only the Ca2+-binding EF-hand motifs were analyzed. Using ML and BI tree based on amino acid sequence similarity, seven loci defined as CaMs and 19 CMLs, with at least 23% identity to CaM, were identified. The phylogenetics, gene structures, EF hand motif organization, and expression characteristics were evaluated. Seven CaM genes, encoding only 4 isoforms, were found in L. japonicus. According to qRT-PCR, four LjCaM isoforms are involved in different rhizobia infection stages. LjCaM1 might be involved in the early rhizobia infection epidermal cells stage. Furthermore, additional structural differences and expression behaviors indicated that LjCMLs may have different potential functions from LjCaMs.
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Affiliation(s)
- Jinqiu Liao
- College of Life Sciences, Sichuan Agricultural UniversityYaan, China
| | - Jiabin Deng
- School of Geography and Tourism, Guizhou Education UniversityGuiyang, China
| | - Zongzhi Qin
- College of Life Sciences, Sichuan Agricultural UniversityYaan, China
| | - Jiayong Tang
- Animal Nutrition Institute, Sichuan Agricultural UniversityChengdu, China
| | - Maorong Shu
- College of Life Sciences, Sichuan Agricultural UniversityYaan, China
| | - Chunbang Ding
- College of Life Sciences, Sichuan Agricultural UniversityYaan, China
| | - Jing Liu
- College of Life Sciences, Sichuan Agricultural UniversityYaan, China
| | - Chao Hu
- College of Life Sciences, Sichuan Agricultural UniversityYaan, China
| | - Ming Yuan
- College of Life Sciences, Sichuan Agricultural UniversityYaan, China
| | - Yan Huang
- College of Life Sciences, Sichuan Agricultural UniversityYaan, China
| | - Ruiwu Yang
- College of Life Sciences, Sichuan Agricultural UniversityYaan, China
| | - Yonghong Zhou
- Triticeae Research Institute, Sichuan Agricultural UniversityChengdu, China
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20
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Doerr N, Wang Y, Kipp KR, Liu G, Benza JJ, Pletnev V, Pavlov TS, Staruschenko A, Mohieldin AM, Takahashi M, Nauli SM, Weimbs T. Regulation of Polycystin-1 Function by Calmodulin Binding. PLoS One 2016; 11:e0161525. [PMID: 27560828 PMCID: PMC4999191 DOI: 10.1371/journal.pone.0161525] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Accepted: 08/08/2016] [Indexed: 11/18/2022] Open
Abstract
Autosomal Dominant Polycystic Kidney Disease (ADPKD) is a common genetic disease that leads to progressive renal cyst growth and loss of renal function, and is caused by mutations in the genes encoding polycystin-1 (PC1) and polycystin-2 (PC2), respectively. The PC1/PC2 complex localizes to primary cilia and can act as a flow-dependent calcium channel in addition to numerous other signaling functions. The exact functions of the polycystins, their regulation and the purpose of the PC1/PC2 channel are still poorly understood. PC1 is an integral membrane protein with a large extracytoplasmic N-terminal domain and a short, ~200 amino acid C-terminal cytoplasmic tail. Most proteins that interact with PC1 have been found to bind via the cytoplasmic tail. Here we report that the PC1 tail has homology to the regulatory domain of myosin heavy chain including a conserved calmodulin-binding motif. This motif binds to CaM in a calcium-dependent manner. Disruption of the CaM-binding motif in PC1 does not affect PC2 binding, cilia targeting, or signaling via heterotrimeric G-proteins or STAT3. However, disruption of CaM binding inhibits the PC1/PC2 calcium channel activity and the flow-dependent calcium response in kidney epithelial cells. Furthermore, expression of CaM-binding mutant PC1 disrupts cellular energy metabolism. These results suggest that critical functions of PC1 are regulated by its ability to sense cytosolic calcium levels via binding to CaM.
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Affiliation(s)
- Nicholas Doerr
- Department of Molecular, Cellular, and Developmental Biology and Neuroscience Research Institute, University of California Santa Barbara, Santa Barbara, CA, United States of America
| | - Yidi Wang
- Department of Molecular, Cellular, and Developmental Biology and Neuroscience Research Institute, University of California Santa Barbara, Santa Barbara, CA, United States of America
| | - Kevin R. Kipp
- Department of Molecular, Cellular, and Developmental Biology and Neuroscience Research Institute, University of California Santa Barbara, Santa Barbara, CA, United States of America
| | - Guangyi Liu
- Department of Molecular, Cellular, and Developmental Biology and Neuroscience Research Institute, University of California Santa Barbara, Santa Barbara, CA, United States of America
- Department of Nephrology, Qilu Hospital, Shandong University, Jinan, China
| | - Jesse J. Benza
- Department of Molecular, Cellular, and Developmental Biology and Neuroscience Research Institute, University of California Santa Barbara, Santa Barbara, CA, United States of America
| | - Vladimir Pletnev
- Department of Structural Biology, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russian Federation
| | - Tengis S. Pavlov
- Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, United States of America
| | - Alexander Staruschenko
- Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, United States of America
| | - Ashraf M. Mohieldin
- Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, United States of America
- University of California Irvine, Medical Campus, Orange, CA, United States of America
| | - Maki Takahashi
- Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, United States of America
- University of California Irvine, Medical Campus, Orange, CA, United States of America
| | - Surya M. Nauli
- Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, United States of America
- University of California Irvine, Medical Campus, Orange, CA, United States of America
| | - Thomas Weimbs
- Department of Molecular, Cellular, and Developmental Biology and Neuroscience Research Institute, University of California Santa Barbara, Santa Barbara, CA, United States of America
- * E-mail:
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21
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Abstract
The myosin holoenzyme is a multimeric protein complex consisting of heavy chains and light chains. Myosin light chains are calmodulin family members which are crucially involved in the mechanoenzymatic function of the myosin holoenzyme. This review examines the diversity of light chains within the myosin superfamily, discusses interactions between the light chain and the myosin heavy chain as well as regulatory and structural functions of the light chain as a subunit of the myosin holoenzyme. It covers aspects of the myosin light chain in the localization of the myosin holoenzyme, protein-protein interactions and light chain binding to non-myosin binding partners. Finally, this review challenges the dogma that myosin regulatory and essential light chain exclusively associate with conventional myosin heavy chains while unconventional myosin heavy chains usually associate with calmodulin.
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Affiliation(s)
- Sarah M Heissler
- a Laboratory of Molecular Physiology; National Heart, Lung, and Blood Institute; National Institutes of Health ; Bethesda , MD USA
| | - James R Sellers
- a Laboratory of Molecular Physiology; National Heart, Lung, and Blood Institute; National Institutes of Health ; Bethesda , MD USA
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22
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Li J, Lu Q, Zhang M. Structural Basis of Cargo Recognition by Unconventional Myosins in Cellular Trafficking. Traffic 2016; 17:822-38. [PMID: 26842936 DOI: 10.1111/tra.12383] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Revised: 01/29/2016] [Accepted: 01/29/2016] [Indexed: 01/17/2023]
Abstract
Unconventional myosins are a superfamily of actin-based molecular motors playing diverse roles including cellular trafficking, mechanical supports, force sensing and transmission, etc. The variable neck and tail domains of unconventional myosins function to bind to specific cargoes including proteins and lipid vesicles and thus are largely responsible for the diverse cellular functions of myosins in vivo. In addition, the tail regions, together with their cognate cargoes, can regulate activities of the motor heads. This review outlines the advances made in recent years on cargo recognition and cargo binding-induced regulation of the activity of several unconventional myosins including myosin-I, V, VI and X in cellular trafficking. We approach this topic by describing a series of high-resolution structures of the neck and tail domains of these unconventional myosins either alone or in complex with their specific cargoes, and by discussing potential implications of these structural studies on cellular trafficking of these myosin motors.
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Affiliation(s)
- Jianchao Li
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Qing Lu
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Mingjie Zhang
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China.,Center of Systems Biology and Human Health, School of Science and Institute for Advanced Study, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
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23
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Cardiac myosin-binding protein C: A protein once at loose ends finds its regulatory groove. Proc Natl Acad Sci U S A 2016; 113:3133-5. [PMID: 26966230 DOI: 10.1073/pnas.1602568113] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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24
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Heissler SM, Sellers JR. Various Themes of Myosin Regulation. J Mol Biol 2016; 428:1927-46. [PMID: 26827725 DOI: 10.1016/j.jmb.2016.01.022] [Citation(s) in RCA: 84] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Revised: 01/12/2016] [Accepted: 01/19/2016] [Indexed: 10/24/2022]
Abstract
Members of the myosin superfamily are actin-based molecular motors that are indispensable for cellular homeostasis. The vast functional and structural diversity of myosins accounts for the variety and complexity of the underlying allosteric regulatory mechanisms that determine the activation or inhibition of myosin motor activity and enable precise timing and spatial aspects of myosin function at the cellular level. This review focuses on the molecular basis of posttranslational regulation of eukaryotic myosins from different classes across species by allosteric intrinsic and extrinsic effectors. First, we highlight the impact of heavy and light chain phosphorylation. Second, we outline intramolecular regulatory mechanisms such as autoinhibition and subsequent activation. Third, we discuss diverse extramolecular allosteric mechanisms ranging from actin-linked regulatory mechanisms to myosin:cargo interactions. At last, we briefly outline the allosteric regulation of myosins with synthetic compounds.
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Affiliation(s)
- Sarah M Heissler
- Laboratory of Molecular Physiology, National Heart, Lung and Blood Institute, National Institutes of Health, 50 South Drive, B50/3529, Bethesda, MD 20892-8015, USA.
| | - James R Sellers
- Laboratory of Molecular Physiology, National Heart, Lung and Blood Institute, National Institutes of Health, 50 South Drive, B50/3529, Bethesda, MD 20892-8015, USA
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25
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Chantler PD. Scallop Adductor Muscles. ACTA ACUST UNITED AC 2016. [DOI: 10.1016/b978-0-444-62710-0.00004-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2023]
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26
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Burakova LP, Natashin PV, Malikova NP, Niu F, Pu M, Vysotski ES, Liu ZJ. All Ca2+-binding loops of light-sensitive ctenophore photoprotein berovin bind magnesium ions: The spatial structure of Mg2+-loaded apo-berovin. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2016; 154:57-66. [DOI: 10.1016/j.jphotobiol.2015.11.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Revised: 11/24/2015] [Accepted: 11/25/2015] [Indexed: 11/30/2022]
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27
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Logvinova DS, Markov DI, Nikolaeva OP, Sluchanko NN, Ushakov DS, Levitsky DI. Does Interaction between the Motor and Regulatory Domains of the Myosin Head Occur during ATPase Cycle? Evidence from Thermal Unfolding Studies on Myosin Subfragment 1. PLoS One 2015; 10:e0137517. [PMID: 26356744 PMCID: PMC4565648 DOI: 10.1371/journal.pone.0137517] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Accepted: 08/18/2015] [Indexed: 11/19/2022] Open
Abstract
Myosin head (myosin subfragment 1, S1) consists of two major structural domains, the motor (or catalytic) domain and the regulatory domain. Functioning of the myosin head as a molecular motor is believed to involve a rotation of the regulatory domain (lever arm) relative to the motor domain during the ATPase cycle. According to predictions, this rotation can be accompanied by an interaction between the motor domain and the C-terminus of the essential light chain (ELC) associated with the regulatory domain. To check this assumption, we applied differential scanning calorimetry (DSC) combined with temperature dependences of fluorescence to study changes in thermal unfolding and the domain structure of S1, which occur upon formation of the ternary complexes S1-ADP-AlF4- and S1-ADP-BeFx that mimic S1 ATPase intermediate states S1**-ADP-Pi and S1*-ATP, respectively. To identify the thermal transitions on the DSC profiles (i.e. to assign them to the structural domains of S1), we compared the DSC data with temperature-induced changes in fluorescence of either tryptophan residues, located only in the motor domain, or recombinant ELC mutants (light chain 1 isoform), which were first fluorescently labeled at different positions in their C-terminal half and then introduced into the S1 regulatory domain. We show that formation of the ternary complexes S1-ADP-AlF4- and S1-ADP-BeFx significantly stabilizes not only the motor domain, but also the regulatory domain of the S1 molecule implying interdomain interaction via ELC. This is consistent with the previously proposed concepts and also adds some new interesting details to the molecular mechanism of the myosin ATPase cycle.
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Affiliation(s)
- Daria S. Logvinova
- A.N. Bach Institute of Biochemistry, Russian Academy of Sciences, Moscow, Russia
- Department of Biochemistry, School of Biology, Moscow State University, Moscow, Russia
- Department of Biotechnology, School of Biology, Vyatka State University, Kirov, Russia
| | - Denis I. Markov
- A.N. Bach Institute of Biochemistry, Russian Academy of Sciences, Moscow, Russia
| | - Olga P. Nikolaeva
- A.N. Belozersky Institute of Physico-Chemical Biology, Moscow State University, Moscow, Russia
| | - Nikolai N. Sluchanko
- A.N. Bach Institute of Biochemistry, Russian Academy of Sciences, Moscow, Russia
| | | | - Dmitrii I. Levitsky
- A.N. Bach Institute of Biochemistry, Russian Academy of Sciences, Moscow, Russia
- A.N. Belozersky Institute of Physico-Chemical Biology, Moscow State University, Moscow, Russia
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28
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Yamaoka S, Hara-Nishimura I. The mitochondrial Ras-related GTPase Miro: views from inside and outside the metazoan kingdom. FRONTIERS IN PLANT SCIENCE 2014; 5:350. [PMID: 25076955 PMCID: PMC4100572 DOI: 10.3389/fpls.2014.00350] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Accepted: 06/30/2014] [Indexed: 05/24/2023]
Abstract
Miro GTPase, a member of the Ras superfamily, consists of two GTPase domains flanking a pair of EF hand motifs and a C-terminal transmembrane domain that anchors the protein to the mitochondrial outer membrane. Since the identification of Miro in humans, a series of studies in metazoans, including mammals and fruit flies, have shown that Miro plays a role in the calcium-dependent regulation of mitochondrial transport along microtubules. However, in non-metazoans, including yeasts, slime molds, and plants, Miro is primarily involved in the maintenance of mitochondrial morphology and homeostasis. Given the high level of conservation of Miro in eukaryotes and the variation in the molecular mechanisms of mitochondrial transport between eukaryotic lineages, Miro may have a common ancestral function in mitochondria, and its roles in the regulation of mitochondrial transport may have been acquired specifically by metazoans after the evolutionary divergence of eukaryotes.
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Affiliation(s)
- Shohei Yamaoka
- Graduate School of Biostudies, Kyoto UniversityKyoto, Japan
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29
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Muthu P, Liang J, Schmidt W, Moore JR, Szczesna-Cordary D. In vitro rescue study of a malignant familial hypertrophic cardiomyopathy phenotype by pseudo-phosphorylation of myosin regulatory light chain. Arch Biochem Biophys 2014; 552-553:29-39. [PMID: 24374283 PMCID: PMC4043912 DOI: 10.1016/j.abb.2013.12.011] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Revised: 12/02/2013] [Accepted: 12/16/2013] [Indexed: 11/18/2022]
Abstract
Pseudo-phosphorylation of cardiac myosin regulatory light chain (RLC) has never been examined as a rescue method to alleviate a cardiomyopathy phenotype brought about by a disease causing mutation in the myosin RLC. This study focuses on the aspartic acid to valine substitution (D166V) in the myosin RLC shown to be associated with a malignant phenotype of familial hypertrophic cardiomyopathy (FHC). The mutation has also been demonstrated to cause severe functional abnormalities in transgenic mice expressing D166V in the heart. To explore this novel rescue strategy, pseudo-phosphorylation of D166V was used to determine whether the D166V-induced detrimental phenotype could be brought back to the level of wild-type (WT) RLC. The S15D substitution at the phosphorylation site of RLC was inserted into the recombinant WT and D166V mutant to mimic constitutively phosphorylated RLC proteins. Non-phosphorylatable (S15A) constructs were used as controls. A multi-faceted approach was taken to determine the effect of pseudo-phosphorylation on the ability of myosin to generate force and motion. Using mutant reconstituted porcine cardiac muscle preparations, we showed an S15D-induced rescue of both the enzymatic and binding properties of D166V-myosin to actin. A significant increase in force production capacity was noted in the in vitro motility assays for S15D-D166V vs. D166V reconstituted myosin. A similar pseudo-phosphorylation induced effect was observed on the D166V-elicited abnormal Ca(2+) sensitivity of force in porcine papillary muscle strips reconstituted with phosphomimic recombinant RLCs. Results from this study demonstrate a novel in vitro rescue strategy that could be utilized in vivo to ameliorate a malignant cardiomyopathic phenotype. We show for the first time that pseudo-RLC phosphorylation can reverse the majority of the mutation-induced phenotypes highlighting the importance of RLC phosphorylation in combating cardiac disease.
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Affiliation(s)
- Priya Muthu
- Department of Molecular and Cellular Pharmacology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Jingsheng Liang
- Department of Molecular and Cellular Pharmacology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - William Schmidt
- Department of Physiology and Biophysics, Boston University School of Medicine, Boston, MA 02118, USA
| | - Jeffrey R Moore
- Department of Physiology and Biophysics, Boston University School of Medicine, Boston, MA 02118, USA
| | - Danuta Szczesna-Cordary
- Department of Molecular and Cellular Pharmacology, University of Miami Miller School of Medicine, Miami, FL 33136, USA.
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Lu Z, Ma XN, Zhang HM, Ji HH, Ding H, Zhang J, Luo D, Sun Y, Li XD. Mouse myosin-19 is a plus-end-directed, high-duty ratio molecular motor. J Biol Chem 2014; 289:18535-48. [PMID: 24825904 DOI: 10.1074/jbc.m114.569087] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Class XIX myosin (Myo19) is a vertebrate-specific unconventional myosin, responsible for the transport of mitochondria. To characterize biochemical properties of Myo19, we prepared recombinant mouse Myo19-truncated constructs containing the motor domain and the IQ motifs using the baculovirus/Sf9 expression system. We identified regulatory light chain (RLC) of smooth muscle/non-muscle myosin-2 as the light chain of Myo19. The actin-activated ATPase activity and the actin-gliding velocity of Myo19-truncated constructs were about one-third and one-sixth as those of myosin-5a, respectively. The apparent affinity of Myo19 to actin was about the same as that of myosin-5a. The RLCs bound to Myo19 could be phosphorylated by myosin light chain kinase, but this phosphorylation had little effect on the actin-activated ATPase activity and the actin-gliding activity of Myo19-truncated constructs. Using dual fluorescence-labeled actin filaments, we determined that Myo19 is a plus-end-directed molecular motor. We found that, similar to that of the high-duty ratio myosin, such as myosin-5a, ADP release rate was comparable with the maximal actin-activated ATPase activity of Myo19, indicating that ADP release is a rate-limiting step for the ATPase cycle of acto-Myo19. ADP strongly inhibited the actin-activated ATPase activity and actin-gliding activity of Myo19-truncated constructs. Based on the above results, we concluded that Myo19 is a high-duty ratio molecular motor moving to the plus-end of the actin filament.
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Affiliation(s)
- Zekuan Lu
- From the Group of Cell Motility and Muscle Contraction, National Laboratory of Integrated Management of Insect Pests and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101 and
| | - Xiao-Nan Ma
- From the Group of Cell Motility and Muscle Contraction, National Laboratory of Integrated Management of Insect Pests and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101 and
| | - Hai-Man Zhang
- From the Group of Cell Motility and Muscle Contraction, National Laboratory of Integrated Management of Insect Pests and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101 and
| | - Huan-Hong Ji
- From the Group of Cell Motility and Muscle Contraction, National Laboratory of Integrated Management of Insect Pests and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101 and
| | - Hao Ding
- From the Group of Cell Motility and Muscle Contraction, National Laboratory of Integrated Management of Insect Pests and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101 and
| | - Jie Zhang
- From the Group of Cell Motility and Muscle Contraction, National Laboratory of Integrated Management of Insect Pests and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101 and
| | - Dan Luo
- From the Group of Cell Motility and Muscle Contraction, National Laboratory of Integrated Management of Insect Pests and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101 and
| | - Yujie Sun
- the Biodynamic Optical Imaging Center (BIOPIC), School of Life Sciences, Peking University, Beijing 100871, China
| | - Xiang-Dong Li
- From the Group of Cell Motility and Muscle Contraction, National Laboratory of Integrated Management of Insect Pests and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101 and
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Batters C, Veigel C, Homsher E, Sellers JR. To understand muscle you must take it apart. Front Physiol 2014; 5:90. [PMID: 24653704 PMCID: PMC3949407 DOI: 10.3389/fphys.2014.00090] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2013] [Accepted: 02/16/2014] [Indexed: 01/08/2023] Open
Abstract
Striated muscle is an elegant system for study at many levels. Much has been learned about the mechanism of contraction from studying the mechanical properties of intact and permeabilized (or skinned) muscle fibers. Structural studies using electron microscopy, X-ray diffraction or spectroscopic probes attached to various contractile proteins were possible because of the highly ordered sarcomeric arrangement of actin and myosin. However, to understand the mechanism of force generation at a molecular level, it is necessary to take the system apart and study the interaction of myosin with actin using in vitro assays. This reductionist approach has lead to many fundamental insights into how myosin powers muscle contraction. In addition, nature has provided scientists with an array of muscles with different mechanical properties and with a superfamily of myosin molecules. Taking advantage of this diversity in myosin structure and function has lead to additional insights into common properties of force generation. This review will highlight the development of the major assays and methods that have allowed this combined reductionist and comparative approach to be so fruitful. This review highlights the history of biochemical and biophysical studies of myosin and demonstrates how a broad comparative approach combined with reductionist studies have led to a detailed understanding of how myosin interacts with actin and uses chemical energy to generate force and movement in muscle contraction and motility in general.
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Affiliation(s)
- Christopher Batters
- Department of Cellular Physiology and Centre for Nanosciences (CeNS), Ludwig-Maximilians-Universität München München, Germany
| | - Claudia Veigel
- Department of Cellular Physiology and Centre for Nanosciences (CeNS), Ludwig-Maximilians-Universität München München, Germany
| | - Earl Homsher
- Physiology Department, University of California Los Angeles Los Angeles, CA, USA
| | - James R Sellers
- Laboratory of Molecular Physiology, National Heart, Lung and Blood Institute, National Institutes of Health Bethesda, MD, USA
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32
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Role of the essential light chain in the activation of smooth muscle myosin by regulatory light chain phosphorylation. J Struct Biol 2013; 185:375-82. [PMID: 24361582 DOI: 10.1016/j.jsb.2013.12.008] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2013] [Revised: 12/15/2013] [Accepted: 12/16/2013] [Indexed: 11/21/2022]
Abstract
The activity of smooth and non-muscle myosin II is regulated by phosphorylation of the regulatory light chain (RLC) at serine 19. The dephosphorylated state of full-length monomeric myosin is characterized by an asymmetric intramolecular head-head interaction that completely inhibits the ATPase activity, accompanied by a hairpin fold of the tail, which prevents filament assembly. Phosphorylation of serine 19 disrupts these head-head interactions by an unknown mechanism. Computational modeling (Tama et al., 2005. J. Mol. Biol. 345, 837-854) suggested that formation of the inhibited state is characterized by both torsional and bending motions about the myosin heavy chain (HC) at a location between the RLC and the essential light chain (ELC). Therefore, altering relative motions between the ELC and the RLC at this locus might disrupt the inhibited state. Based on this hypothesis we have derived an atomic model for the phosphorylated state of the smooth muscle myosin light chain domain (LCD). This model predicts a set of specific interactions between the N-terminal residues of the RLC with both the myosin HC and the ELC. Site directed mutagenesis was used to show that interactions between the phosphorylated N-terminus of the RLC and helix-A of the ELC are required for phosphorylation to activate smooth muscle myosin.
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33
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Structural coupling of the EF hand and C-terminal GTPase domains in the mitochondrial protein Miro. EMBO Rep 2013; 14:968-74. [PMID: 24071720 DOI: 10.1038/embor.2013.151] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Revised: 08/21/2013] [Accepted: 08/22/2013] [Indexed: 01/08/2023] Open
Abstract
Miro is a highly conserved calcium-binding GTPase at the regulatory nexus of mitochondrial transport and autophagy. Here we present crystal structures comprising the tandem EF hand and carboxy terminal GTPase (cGTPase) domains of Drosophila Miro. The structures reveal two previously unidentified 'hidden' EF hands, each paired with a canonical EF hand. Each EF hand pair is bound to a helix that structurally mimics an EF hand ligand. A key nucleotide-sensing element and a Pink1 phosphorylation site both lie within an extensive EF hand-cGTPase interface. Our results indicate structural mechanisms for calcium, nucleotide and phosphorylation-dependent regulation of mitochondrial function by Miro.
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34
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Kull FJ, Endow SA. Force generation by kinesin and myosin cytoskeletal motor proteins. J Cell Sci 2013; 126:9-19. [PMID: 23487037 DOI: 10.1242/jcs.103911] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Kinesins and myosins hydrolyze ATP, producing force that drives spindle assembly, vesicle transport and muscle contraction. How do motors do this? Here we discuss mechanisms of motor force transduction, based on their mechanochemical cycles and conformational changes observed in crystal structures. Distortion or twisting of the central β-sheet - proposed to trigger actin-induced Pi and ADP release by myosin, and microtubule-induced ADP release by kinesins - is shown in a movie depicting the transition between myosin ATP-like and nucleotide-free states. Structural changes in the switch I region form a tube that governs ATP hydrolysis and Pi release by the motors, explaining the essential role of switch I in hydrolysis. Comparison of the motor power strokes reveals that each stroke begins with the force-amplifying structure oriented opposite to the direction of rotation or swing. Motors undergo changes in their mechanochemical cycles in response to small-molecule inhibitors, several of which bind to kinesins by induced fit, trapping the motors in a state that resembles a force-producing conformation. An unusual motor activator specifically increases mechanical output by cardiac myosin, potentially providing valuable information about its mechanism of function. Further study is essential to understand motor mechanochemical coupling and energy transduction, and could lead to new therapies to treat human disease.
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Affiliation(s)
- F Jon Kull
- Department of Chemistry, Dartmouth College, Hanover, NH 03755, USA
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35
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Characterizations of myosin essential light chain's N-terminal truncation mutant Δ43 in transgenic mouse papillary muscles by using tension transients in response to sinusoidal length alterations. J Muscle Res Cell Motil 2013; 34:93-105. [PMID: 23397074 DOI: 10.1007/s10974-013-9337-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2012] [Accepted: 01/24/2013] [Indexed: 10/27/2022]
Abstract
Cross-bridge kinetics were studied at 20 °C in cardiac muscle strips from transgenic (Tg) mice expressing N-terminal 43 amino acid truncation mutation (Δ43) of myosin essential light chain (ELC), and the results were compared to those from Tg-wild type (WT) mice. Sinusoidal length changes were applied to activated skinned papillary muscle strips to induce tension transients, from which two exponential processes were deduced to characterize the cross-bridge kinetics. Their two rate constants were studied as functions of ATP, phosphate (Pi), ADP, and Ca(2+) concentrations to characterize elementary steps of the cross-bridge cycle consisting of six states. Our results demonstrate for the first time that the cross-bridge kinetics of Δ43 are accelerated owing to an acceleration of the rate constant k 2 of the cross-bridge detachment step, and that the number of strongly attached cross-bridges are decreased because of a reduction of the equilibrium constant K 4 of the force generation step. The isometric tension and stiffness of Δ43 are diminished compared to WT, but the force per cross-bridge is not changed. Stiffness measurement during rigor induction demonstrates a reduction in the stiffness in Δ43, indicating that the N-terminal extension of ELC forms an extra linkage between the myosin cross-bridge and actin. The tension-pCa study demonstrates that there is no Ca(2+) sensitivity change with Δ43, but the cooperativity is diminished. These results demonstrate the importance of the N-terminal extension of ELC in maintaining the myosin motor function during force generation and optimal cardiac performance.
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36
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Bertini I, Borsi V, Cerofolini L, Das Gupta S, Fragai M, Luchinat C. Solution structure and dynamics of human S100A14. J Biol Inorg Chem 2013; 18:183-194. [PMID: 23197251 DOI: 10.1007/s00775-012-0963-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2012] [Accepted: 11/06/2012] [Indexed: 01/12/2023]
Abstract
Human S100A14 is a member of the EF-hand calcium-binding protein family that has only recently been described in terms of its functional and pathological properties. The protein is overexpressed in a variety of tumor cells and it has been shown to trigger receptor for advanced glycation end products (RAGE)-dependent signaling in cell cultures. The solution structure of homodimeric S100A14 in the apo state has been solved at physiological temperature. It is shown that the protein does not bind calcium(II) ions and exhibits a "semi-open" conformation that thus represents the physiological structure of the S100A14. The lack of two ligands in the canonical EF-hand calcium(II)-binding site explains the negligible affinity for calcium(II) in solution, and the exposed cysteines and histidine account for the observed precipitation in the presence of zinc(II) or copper(II) ions.
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Affiliation(s)
- Ivano Bertini
- Magnetic Resonance Center (CERM), University of Florence, Via L. Sacconi 6, 50019, Sesto Fiorentino, Italy.,Department of Chemistry, University of Florence, Via della Lastruccia 3, 50019, Sesto Fiorentino, Italy
| | - Valentina Borsi
- Magnetic Resonance Center (CERM), University of Florence, Via L. Sacconi 6, 50019, Sesto Fiorentino, Italy
| | - Linda Cerofolini
- Magnetic Resonance Center (CERM), University of Florence, Via L. Sacconi 6, 50019, Sesto Fiorentino, Italy
| | - Soumyasri Das Gupta
- Magnetic Resonance Center (CERM), University of Florence, Via L. Sacconi 6, 50019, Sesto Fiorentino, Italy
| | - Marco Fragai
- Magnetic Resonance Center (CERM), University of Florence, Via L. Sacconi 6, 50019, Sesto Fiorentino, Italy.,Department of Chemistry, University of Florence, Via della Lastruccia 3, 50019, Sesto Fiorentino, Italy
| | - Claudio Luchinat
- Magnetic Resonance Center (CERM), University of Florence, Via L. Sacconi 6, 50019, Sesto Fiorentino, Italy. .,Department of Chemistry, University of Florence, Via della Lastruccia 3, 50019, Sesto Fiorentino, Italy.
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37
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Guhathakurta P, Prochniewicz E, Muretta JM, Titus MA, Thomas DD. Allosteric communication in Dictyostelium myosin II. J Muscle Res Cell Motil 2012; 33:305-12. [PMID: 22752265 DOI: 10.1007/s10974-012-9304-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2012] [Accepted: 05/22/2012] [Indexed: 12/14/2022]
Abstract
Myosin's affinities for nucleotides and actin are reciprocal. Actin-binding substantially reduces the affinity of ATP for myosin, but the effect of actin on myosin's ADP affinity is quite variable among myosin isoforms, serving as the principal mechanism for tuning the actomyosin system to specific physiological purposes. To understand the structural basis of this variable relationship between actin and ADP binding, we studied several constructs of the catalytic domain of Dictyostelium myosin II, varying their length (from the N-terminal origin) and cysteine content. The constructs varied considerably in their actin-activated ATPase activity and in the effect of actin on ADP affinity. Actin had no significant effect on ADP affinity for a single-cysteine catalytic domain construct, a double-cysteine construct partially restored the actin-dependence of ADP binding, and restoration of all native Cys restored it further, but full restoration of function (similar to that of skeletal muscle myosin II) was obtained only by adding all native Cys and an artificial lever arm extension. Pyrene-actin fluorescence confirmed these effects on ADP binding to actomyosin. We conclude that myosin's Cys content and lever arm both allosterically modulate the reciprocal affinities of myosin for ADP and actin, a key determinant of the biological functions of myosin isoforms.
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Affiliation(s)
- Piyali Guhathakurta
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, 6-155 Jackson Hall, 321 Church St. SE, Minneapolis, MN 55455, USA
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38
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Ni S, Hong F, Haldeman BD, Baker JE, Facemyer KC, Cremo CR. Modification of interface between regulatory and essential light chains hampers phosphorylation-dependent activation of smooth muscle myosin. J Biol Chem 2012; 287:22068-79. [PMID: 22549781 DOI: 10.1074/jbc.m112.343491] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We examined the regulatory importance of interactions between regulatory light chain (RLC), essential light chain (ELC), and adjacent heavy chain (HC) in the regulatory domain of smooth muscle heavy meromyosin. After mutating the HC, RLC, and/or ELC to disrupt their predicted interactions (using scallop myosin coordinates), we measured basal ATPase, V(max), and K(ATPase) of actin-activated ATPase, actin-sliding velocities, rigor binding to actin, and kinetics of ATP binding and ADP release. If unphosphorylated, all mutants were similar to wild type showing turned-off behaviors. In contrast, if phosphorylated, mutation of RLC residues smM129Q and smG130C in the F-G helix linker, which interact with the ELC (Ca(2+) binding in scallop), was sufficient to abolish motility and diminish ATPase activity, without altering other parameters. ELC mutations within this interacting ELC loop (smR20M and smK25A) were normal, but smM129Q/G130C-R20M or -K25A showed a partially recovered phenotype suggesting that interaction between the RLC and ELC is important. A molecular dynamics study suggested that breaking the RLC/ELC interface leads to increased flexibility at the interface and ELC-binding site of the HC. We hypothesize that this leads to hampered activation by allowing a pre-existing equilibrium between activated and inhibited structural distributions (Vileno, B., Chamoun, J., Liang, H., Brewer, P., Haldeman, B. D., Facemyer, K. C., Salzameda, B., Song, L., Li, H. C., Cremo, C. R., and Fajer, P. G. (2011) Broad disorder and the allosteric mechanism of myosin II regulation by phosphorylation. Proc. Natl. Acad. Sci. U.S.A. 108, 8218-8223) to be biased strongly toward the inhibited distribution even when the RLC is phosphorylated. We propose that an important structural function of RLC phosphorylation is to promote or assist in the maintenance of an intact RLC/ELC interface. If the RLC/ELC interface is broken, the off-state structures are no longer destabilized by phosphorylation.
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Affiliation(s)
- Shaowei Ni
- Department of Biochemistry and Molecular Biology, University of Nevada School of Medicine, Reno, Nevada 89557, USA
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39
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Calcium-induced changes in calmodulin structural dynamics and thermodynamics. Int J Biol Macromol 2012; 50:1011-7. [DOI: 10.1016/j.ijbiomac.2012.02.017] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2011] [Revised: 02/12/2012] [Accepted: 02/16/2012] [Indexed: 01/29/2023]
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40
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A novel Myosin essential light chain mutation causes hypertrophic cardiomyopathy with late onset and low expressivity. Biochem Res Int 2012; 2012:685108. [PMID: 22957257 PMCID: PMC3432877 DOI: 10.1155/2012/685108] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2011] [Accepted: 02/07/2012] [Indexed: 02/02/2023] Open
Abstract
Hypertrophic cardiomyopathy (HCM) is caused by mutations in genes encoding sarcomere proteins. Mutations in MYL3, encoding the essential light chain of myosin, are rare and have been associated with sudden death. Both recessive and dominant patterns of inheritance have been suggested. We studied a large family with a 38-year-old asymptomatic HCM-affected male referred because of a murmur. The patient had HCM with left ventricular hypertrophy (max WT 21 mm), a resting left ventricular outflow gradient of 36 mm Hg, and left atrial dilation (54 mm). Genotyping revealed heterozygosity for a novel missense mutation, p.V79I, in MYL3. The mutation was not found in 300 controls, and the patient had no mutations in 10 sarcomere genes. Cascade screening revealed a further nine heterozygote mutation carriers, three of whom had ECG and/or echocardiographic abnormalities but did not fulfil diagnostic criteria for HCM. The penetrance, if we consider this borderline HCM the phenotype of the p.V79I mutation, was 40%, but the mean age of the nonpenetrant mutation carriers is 15, while the mean age of the penetrant mutation carriers is 47. The mutation affects a conserved valine replacing it with a larger isoleucine residue in the region of contact between the light chain and the myosin lever arm. In conclusion, MYL3 mutations can present with low expressivity and late onset.
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41
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Romano D, Brandmeier BD, Sun YB, Trentham DR, Irving M. Orientation of the N-terminal lobe of the myosin regulatory light chain in skeletal muscle fibers. Biophys J 2012; 102:1418-26. [PMID: 22455925 DOI: 10.1016/j.bpj.2012.02.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2011] [Revised: 02/03/2012] [Accepted: 02/07/2012] [Indexed: 11/17/2022] Open
Abstract
The orientation of the N-terminal lobe of the myosin regulatory light chain (RLC) in demembranated fibers of rabbit psoas muscle was determined by polarized fluorescence. The native RLC was replaced by a smooth muscle RLC with a bifunctional rhodamine probe attached to its A, B, C, or D helix. Fiber fluorescence data were interpreted using the crystal structure of the head domain of chicken skeletal myosin in the nucleotide-free state. The peak angle between the lever axis of the myosin head and the fiber or actin filament axis was 100-110° in relaxation, isometric contraction, and rigor. In each state the hook helix was at an angle of ∼40° to the lever/filament plane. The in situ orientation of the RLC D and E helices, and by implication of its N- and C-lobes, was similar in smooth and skeletal RLC isoforms. The angle between these two RLC lobes in rigor fibers was different from that in the crystal structure. These results extend previous crystallographic evidence for bending between the two lobes of the RLC to actin-attached myosin heads in muscle fibers, and suggest that such bending may have functional significance in contraction and regulation of vertebrate striated muscle.
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Affiliation(s)
- Daniela Romano
- Medical Research Council, National Institute for Medical Research, London, United Kingdom
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42
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Baumann BAJ, Taylor DW, Huang Z, Tama F, Fagnant PM, Trybus KM, Taylor KA. Phosphorylated smooth muscle heavy meromyosin shows an open conformation linked to activation. J Mol Biol 2011; 415:274-87. [PMID: 22079364 DOI: 10.1016/j.jmb.2011.10.047] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2011] [Revised: 10/22/2011] [Accepted: 10/27/2011] [Indexed: 11/26/2022]
Abstract
Smooth muscle myosin and smooth muscle heavy meromyosin (smHMM) are activated by regulatory light chain phosphorylation, but the mechanism remains unclear. Dephosphorylated, inactive smHMM assumes a closed conformation with asymmetric intramolecular head-head interactions between motor domains. The "free head" can bind to actin, but the actin binding interface of the "blocked head" is involved in interactions with the free head. We report here a three-dimensional structure for phosphorylated, active smHMM obtained using electron crystallography of two-dimensional arrays. Head-head interactions of phosphorylated smHMM resemble those found in the dephosphorylated state but occur between different molecules, not within the same molecule. The light chain binding domain structure of phosphorylated smHMM differs markedly from that of the "blocked" head of dephosphorylated smHMM. We hypothesize that regulatory light chain phosphorylation opens the inhibited conformation primarily by its effect on the blocked head. Singly phosphorylated smHMM is not compatible with the closed conformation if the blocked head is phosphorylated. This concept has implications for the extent of myosin activation at low levels of phosphorylation in smooth muscle.
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Affiliation(s)
- Bruce A J Baumann
- Institute of Molecular Biophysics, Florida State University, Tallahassee, FL 32306, USA
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43
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Crystal structure of a phosphorylated light chain domain of scallop smooth-muscle myosin. Biophys J 2011; 101:2185-9. [PMID: 22067157 PMCID: PMC3207169 DOI: 10.1016/j.bpj.2011.09.028] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2011] [Revised: 09/01/2011] [Accepted: 09/06/2011] [Indexed: 01/07/2023] Open
Abstract
We have determined the crystal structure of a phosphorylated smooth-muscle myosin light chain domain (LCD). This reconstituted LCD is of a sea scallop catch muscle myosin with its phosphorylatable regulatory light chain (RLC SmoA). In the crystal structure, Arg(16), an arginine residue that is present in this isoform but not in vertebrate smooth-muscle RLC, stabilizes the phosphorylation site. This arginine interacts with the carbonyl group of the phosphorylation-site serine in the unphosphorylated LCD (determined previously), and with the phosphate group when the serine is phosphorylated. However, the overall conformation of the LCD is essentially unchanged upon phosphorylation. This result provides additional evidence that phosphorylation of the RLC is unlikely to act as an on-switch in regulation of scallop catch muscle myosin.
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44
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Beck MR, Otey CA, Campbell SL. Structural characterization of the interactions between palladin and α-actinin. J Mol Biol 2011; 413:712-25. [PMID: 21925511 PMCID: PMC3226707 DOI: 10.1016/j.jmb.2011.08.059] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2011] [Revised: 08/29/2011] [Accepted: 08/30/2011] [Indexed: 12/11/2022]
Abstract
The interaction between α-actinin and palladin, two actin-cross-linking proteins, is essential for proper bidirectional targeting of these proteins. As a first step toward understanding the role of this complex in organizing cytoskeletal actin, we have characterized binding interactions between the EF-hand domain of α-actinin (Act-EF34) and peptides derived from palladin and generated an NMR-derived structural model for the Act-EF34/palladin peptide complex. The critical binding site residues are similar to an α-actinin binding motif previously suggested for the complex between Act-EF34 and titin Z-repeats. The structure-based model of the Act-EF34/palladin peptide complex expands our understanding of binding specificity between the scaffold protein α-actinin and various ligands, which appears to require an α-helical motif containing four hydrophobic residues, common to many α-actinin ligands. We also provide evidence that the Family X mutation in palladin, associated with a highly penetrant form of pancreatic cancer, does not interfere with α-actinin binding.
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Affiliation(s)
- Moriah R. Beck
- Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599, USA
| | - Carol A. Otey
- Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599, USA
- Department of Cell and Molecular Physiology, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599, USA
| | - Sharon L. Campbell
- Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599, USA
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45
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Grabarek Z. Insights into modulation of calcium signaling by magnesium in calmodulin, troponin C and related EF-hand proteins. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2011; 1813:913-21. [PMID: 21262274 DOI: 10.1016/j.bbamcr.2011.01.017] [Citation(s) in RCA: 96] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 11/08/2010] [Revised: 01/11/2011] [Accepted: 01/12/2011] [Indexed: 10/18/2022]
Abstract
The Ca(2+)-binding helix-loop-helix structural motif called "EF-hand" is a common building block of a large family of proteins that function as intracellular Ca(2+)-receptors. These proteins respond specifically to micromolar concentrations of Ca(2+) in the presence of ~1000-fold excess of the chemically similar divalent cation Mg(2+). The intracellular free Mg(2+) concentration is tightly controlled in a narrow range of 0.5-1.0mM, which at the resting Ca(2+) levels is sufficient to fully or partially saturate the Ca(2+)-binding sites of many EF-hand proteins. Thus, to convey Ca(2+) signals, EF-hand proteins must respond differently to Ca(2+) than to Mg(2+). In this review the structural aspects of Mg(2+) binding to EF-hand proteins are considered and interpreted in light of the recently proposed two-step Ca(2+)-binding mechanism (Grabarek, Z., J. Mol. Biol., 2005, 346, 1351). It is proposed that, due to stereochemical constraints imposed by the two-EF-hand domain structure, the smaller Mg(2+) ion cannot engage the ligands of an EF-hand in the same way as Ca(2+) and defaults to stabilizing the apo-like conformation of the EF-hand. It is proposed that Mg(2+) plays an active role in the Ca(2+)-dependent regulation of cellular processes by stabilizing the "off state" of some EF-hand proteins, thereby facilitating switching off their respective target enzymes at the resting Ca(2+) levels. Therefore, some pathological conditions attributed to Mg(2+) deficiency might be related to excessive activation of underlying Ca(2+)-regulated cellular processes. This article is part of a Special Issue entitled: 11th European Symposium on Calcium.
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Affiliation(s)
- Zenon Grabarek
- Boston Biomedical Research Institute, 64 Grove Street, Watertown, MA 02472-2829, USA.
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Visualizing key hinges and a potential major source of compliance in the lever arm of myosin. Proc Natl Acad Sci U S A 2010; 108:114-9. [PMID: 21149681 DOI: 10.1073/pnas.1016288107] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We have determined the 2.3-Å-resolution crystal structure of a myosin light chain domain, corresponding to one type found in sea scallop catch ("smooth") muscle. This structure reveals hinges that may function in the "on" and "off" states of myosin. The molecule adopts two different conformations about the heavy chain "hook" and regulatory light chain (RLC) helix D. This conformational change results in extended and compressed forms of the lever arm whose lengths differ by 10 Å. The heavy chain hook and RLC helix D hinges could thus serve as a potential major and localized source of cross-bridge compliance during the contractile cycle. In addition, in one of the molecules of the crystal, part of the RLC N-terminal extension is seen in atomic detail and forms a one-turn alpha-helix that interacts with RLC helix D. This extension, whose sequence is highly variable in different myosins, may thus modulate the flexibility of the lever arm. Moreover, the relative proximity of the phosphorylation site to the helix D hinge suggests a potential role for conformational changes about this hinge in the transition between the on and off states of regulated myosins.
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Modeling smooth muscle myosin's two heads: long-lived enzymatic roles and phosphorylation-dependent equilibria. Biophys J 2010; 99:1129-38. [PMID: 20712996 DOI: 10.1016/j.bpj.2010.06.018] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2010] [Revised: 06/07/2010] [Accepted: 06/11/2010] [Indexed: 11/21/2022] Open
Abstract
Smooth muscle myosin has two heads, each capable of interacting with actin to generate force and/or motion as it hydrolyzes ATP. These heads are inhibited when their associated regulatory light chain is unphosphorylated (0P), becoming active and hydrolyzing ATP maximally when phosphorylated (2P). Interestingly, with only one of the two regulatory light chains phosphorylated (1P), smooth muscle myosin is active but its ATPase rate is <2P. To explain published 1P single ATP turnover and steady-state ATPase activities, we propose a kinetic model in which 1P myosin exists in an equilibrium between being fully active (2P) and inhibited (0P). Based on the single ATP turnover data, we also propose that each 2P head adopts a hydrolytic role distinct from its partner at any point in time, i.e., one head strongly binds actin and hydrolyzes ATP at its actin-activated rate while the other weakly binds actin. Surprisingly, the heads switch roles slowly (<0.1 s(-1)), suggesting that their activities are not independent. The phosphorylation-dependent equilibrium between active and inhibited states and the hydrolytic role that each head adopts during its interaction with actin may have implications for understanding regulation and mechanical performance of other members of the myosin family of molecular motors.
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Ushakov DS, Caorsi V, Ibanez-Garcia D, Manning HB, Konitsiotis AD, West TG, Dunsby C, French PM, Ferenczi MA. Response of rigor cross-bridges to stretch detected by fluorescence lifetime imaging microscopy of myosin essential light chain in skeletal muscle fibers. J Biol Chem 2010; 286:842-50. [PMID: 21056977 DOI: 10.1074/jbc.m110.149526] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
We applied fluorescence lifetime imaging microscopy to map the microenvironment of the myosin essential light chain (ELC) in permeabilized skeletal muscle fibers. Four ELC mutants containing a single cysteine residue at different positions in the C-terminal half of the protein (ELC-127, ELC-142, ELC-160, and ELC-180) were generated by site-directed mutagenesis, labeled with 7-diethylamino-3-((((2-iodoacetamido)ethyl)amino)carbonyl)coumarin, and introduced into permeabilized rabbit psoas fibers. Binding to the myosin heavy chain was associated with a large conformational change in the ELC. When the fibers were moved from relaxation to rigor, the fluorescence lifetime increased for all label positions. However, when 1% stretch was applied to the rigor fibers, the lifetime decreased for ELC-127 and ELC-180 but did not change for ELC-142 and ELC-160. The differential change of fluorescence lifetime demonstrates the shift in position of the C-terminal domain of ELC with respect to the heavy chain and reveals specific locations in the lever arm region sensitive to the mechanical strain propagating from the actin-binding site to the lever arm.
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Affiliation(s)
- Dmitry S Ushakov
- National Heart and Lung Institute, Imperial College London, London SW7 2AZ, United Kingdom.
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MDR1 function is sensitive to the phosphorylation state of myosin regulatory light chain. Biochem Biophys Res Commun 2010; 398:7-12. [PMID: 20510202 DOI: 10.1016/j.bbrc.2010.05.084] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2010] [Accepted: 05/14/2010] [Indexed: 11/24/2022]
Abstract
Multiple drug resistance protein 1 (MDR1) is composed of two homologous halves separated by an intracellular linker region. The linker has been reported to bind myosin regulatory light chain (RLC), but it is not clear how this can occur in the context of a myosin II complex. We characterized MDR1-RLC interactions and determined that binding occurs via the amino terminal of the RLC, a domain that typically binds myosin heavy chain. MDR1-RLC interactions were sensitive to the phosphorylation state of the light chain in that phosphorylation by myosin light chain kinase (MLCK) resulted in a loss of binding in vitro. We used ML-7, a specific inhibitor of MLCK, to study the functional consequences of disrupting RLC phosphorylation in intact cells. Pretreatment of polarized Madin-Darby canine kidney cells stably expressing MDR1 with ML-7 produced a significant increase in apical to basal permeability and a corresponding decrease in the efflux ratio (threefold; p<0.01) of [(3)H]-digoxin, a classic MDR1 substrate. Together these data show that MDR1-mediated transport of [(3)H]-digoxin can be modulated by pharmacological manipulation of myosin RLC, but direct MDR1-RLC interactions are atypical and not explained by the structure of the myosin II holoenzyme.
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