1
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Schmidt AA, Grosberg AY, Grosberg A. A novel kinetic model to demonstrate the independent effects of ATP and ADP/Pi concentrations on sarcomere function. PLoS Comput Biol 2024; 20:e1012321. [PMID: 39102392 DOI: 10.1371/journal.pcbi.1012321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Accepted: 07/12/2024] [Indexed: 08/07/2024] Open
Abstract
Understanding muscle contraction mechanisms is a standing challenge, and one of the approaches has been to create models of the sarcomere-the basic contractile unit of striated muscle. While these models have been successful in elucidating many aspects of muscle contraction, they fall short in explaining the energetics of functional phenomena, such as rigor, and in particular, their dependence on the concentrations of the biomolecules involved in the cross-bridge cycle. Our hypothesis posits that the stochastic time delay between ATP adsorption and ADP/Pi release in the cross-bridge cycle necessitates a modeling approach where the rates of these two reaction steps are controlled by two independent parts of the total free energy change of the hydrolysis reaction. To test this hypothesis, we built a two-filament, stochastic-mechanical half-sarcomere model that separates the energetic roles of ATP and ADP/Pi in the cross-bridge cycle's free energy landscape. Our results clearly demonstrate that there is a nontrivial dependence of the cross-bridge cycle's kinetics on the independent concentrations of ATP, ADP, and Pi. The simplicity of the proposed model allows for analytical solutions of the more basic systems, which provide novel insight into the dominant mechanisms driving some of the experimentally observed contractile phenomena.
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Affiliation(s)
- Andrew A Schmidt
- Department of Biomedical Engineering, University of California, Irvine, Irvine, California, United States of America
- UCI Edwards Lifesciences Foundation Cardiovascular Innovation and Research Center (CIRC), University of California, Irvine, Irvine, California, United States of America
| | - Alexander Y Grosberg
- Department of Physics and Center for Soft Matter Research, New York University, New York, New York, United States of America
| | - Anna Grosberg
- Department of Biomedical Engineering, University of California, Irvine, Irvine, California, United States of America
- UCI Edwards Lifesciences Foundation Cardiovascular Innovation and Research Center (CIRC), University of California, Irvine, Irvine, California, United States of America
- Department of Chemical & Biomolecular Engineering, University of California, Irvine, Irvine, California, United States of America
- The NSF-Simons Center for Multiscale Cell Fate Research and Sue and Bill Gross Stem Cell Research Center and Center for Complex Biological Systems, University of California, Irvine, Irvine, California, United States of America
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2
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Hei B, Tardiff JC, Schwartz SD. Human cardiac β-myosin powerstroke energetics: Thin filament, Pi displacement, and mutation effects. Biophys J 2024:S0006-3495(24)00451-X. [PMID: 39001604 DOI: 10.1016/j.bpj.2024.07.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2024] [Revised: 07/01/2024] [Accepted: 07/09/2024] [Indexed: 07/25/2024] Open
Abstract
The powerstroke of human cardiac β-myosin is an important stage of the cross-bridge cycle that generates force for muscle contraction. However, the starting structure of this process has never been resolved, and the relative timing of the powerstroke and inorganic phosphate (Pi) release is still controversial. In this study, we generated an atomistic model of myosin on the thin filament and utilized metadynamics simulations to predict the absent starting structure of the powerstroke. We demonstrated that the displacement of Pi from the active site during the powerstroke is likely necessary, reducing the energy barrier of the conformation change. The effects of the presence of the thin filament, the hypertrophic cardiomyopathy mutation R712L, and the binding of mavacamten on the powerstroke process were also investigated.
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Affiliation(s)
- Bai Hei
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona
| | - Jil C Tardiff
- Department of Biomedical Engineering, University of Arizona, Tucson, Arizona
| | - Steven D Schwartz
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona.
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3
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Freedman H, Tuszynski JA. Study of the Myosin Relay Helix Peptide by Molecular Dynamics Simulations, Pump-Probe and 2D Infrared Spectroscopy. Int J Mol Sci 2024; 25:6406. [PMID: 38928112 PMCID: PMC11203622 DOI: 10.3390/ijms25126406] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2024] [Revised: 05/07/2024] [Accepted: 05/29/2024] [Indexed: 06/28/2024] Open
Abstract
The Davydov model was conjectured to describe how an amide I excitation created during ATP hydrolysis in myosin might be significant in providing energy to drive myosin's chemomechanical cycle. The free energy surfaces of the myosin relay helix peptide dissolved in 2,2,2-trifluoroethanol (TFE), determined by metadynamics simulations, demonstrate local minima differing in free energy by only ~2 kT, corresponding to broken and stabilized hydrogen bonds, respectively. Experimental pump-probe and 2D infrared spectroscopy were performed on the peptide dissolved in TFE. The relative heights of two peaks seen in the pump-probe data and the corresponding relative volumes of diagonal peaks seen in the 2D-IR spectra at time delays between 0.5 ps and 1 ps differ noticeably from what is seen at earlier or later time delays or in the linear spectrum, indicating that a vibrational excitation may influence the conformational state of this helix. Thus, it is possible that the presence of an amide I excitation may be a direct factor in the conformational state taken on by the myosin relay helix following ATP hydrolysis in myosin.
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Affiliation(s)
- Holly Freedman
- Center for Molecular Spectroscopy and Dynamics, Institute for Basic Science (IBS), Seoul 02841, Republic of Korea
- Department of Chemistry, Korea University, Seoul 02841, Republic of Korea
- Department of Medicinal Chemistry, College of Pharmacy, University of Utah, 2000 East 30 South Skaggs 306, Salt Lake City, UT 84112, USA
| | - Jack A. Tuszynski
- Department of Physics, University of Alberta, 11335 Saskatchewan Dr NW, Edmonton, AB T6G 2M9, Canada;
- DIMEAS, Politecnico di Torino, Corso Duca degli Abruzzi 24, I-1029 Turin, Italy
- Department of Data Science and Engineering, The Silesian University of Technology, 44-100 Gliwice, Poland
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4
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Chakraborti A, Tardiff JC, Schwartz SD. Myosin-Catalyzed ATP Hydrolysis in the Presence of Disease-Causing Mutations: Mavacamten as a Way to Repair Mechanism. J Phys Chem B 2024; 128:4716-4727. [PMID: 38708944 PMCID: PMC11103257 DOI: 10.1021/acs.jpcb.4c01601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/07/2024]
Abstract
Hypertrophic cardiomyopathy is one of the most common forms of genetic cardiomyopathy. Mavacamten is a first-in-class myosin modulator that was identified via activity screening on the wild type, and it is FDA-approved for the treatment of obstructive hypertrophic cardiomyopathy (HCM). The drug selectively binds to the cardiac β-myosin, inhibiting myosin function to decrease cardiac contractility. Though the drug is thought to affect multiple steps of the myosin cross-bridge cycle, its detailed mechanism of action is still under investigation. Individual steps in the overall cross-bridge cycle must be queried to elucidate the full mechanism of action. In this study, we utilize the rare-event method of transition path sampling to generate reactive trajectories to gain insights into the action of the drug on the dynamics and rate of the ATP hydrolysis step for human cardiac β-myosin. We study three known HCM causative myosin mutations: R453C, P710R, and R712L to observe the effect of the drug on the alterations caused by these mutations in the chemical step. Since the crystal structure of the drug-bound myosin was not available at the time of this work, we created a model of the drug-bound system utilizing a molecular docking approach. We find a significant effect of the drug in one case, where the actual mechanism of the reaction is altered from the wild type by mutation. The drug restores both the rate of hydrolysis to the wildtype level and the mechanism of the reaction. This is a way to check the effect of the drug on untested mutations.
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Affiliation(s)
- Ananya Chakraborti
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721, United States
| | - Jil C Tardiff
- Department of Biomedical Engineering, University of Arizona, Tucson, Arizona 85724, United States
| | - Steven D Schwartz
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721, United States
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5
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Garrido-Casado M, Asensio-Juárez G, Talayero VC, Vicente-Manzanares M. Engines of change: Nonmuscle myosin II in mechanobiology. Curr Opin Cell Biol 2024; 87:102344. [PMID: 38442667 DOI: 10.1016/j.ceb.2024.102344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2023] [Revised: 02/04/2024] [Accepted: 02/05/2024] [Indexed: 03/07/2024]
Abstract
The emergence of mechanobiology has unveiled complex mechanisms by which cells adjust intracellular force production to their needs. Most communicable intracellular forces are generated by myosin II, an actin-associated molecular motor that transforms adenosine triphosphate (ATP) hydrolysis into contraction in nonmuscle and muscle cells. Myosin II-dependent force generation is tightly regulated, and deregulation is associated with specific pathologies. Here, we focus on the role of myosin II (nonmuscle myosin II, NMII) in force generation and mechanobiology. We outline the regulation and molecular mechanism of force generation by NMII, focusing on the actual outcome of contraction, that is, force application to trigger mechanosensitive events or the building of dissipative structures. We describe how myosin II-generated forces drive two major types of events: modification of the cellular morphology and/or triggering of genetic programs, which enhance the ability of cells to adapt to, or modify, their microenvironment. Finally, we address whether targeting myosin II to impair or potentiate its activity at the motor level is a viable therapeutic strategy, as illustrated by recent examples aimed at modulating cardiac myosin II function in heart disease.
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Affiliation(s)
- Marina Garrido-Casado
- Molecular Mechanisms Program, Centro de Investigación del Cáncer/ Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC) and University of Salamanca, 37007 Salamanca, Spain
| | - Gloria Asensio-Juárez
- Molecular Mechanisms Program, Centro de Investigación del Cáncer/ Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC) and University of Salamanca, 37007 Salamanca, Spain
| | - Vanessa C Talayero
- Molecular Mechanisms Program, Centro de Investigación del Cáncer/ Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC) and University of Salamanca, 37007 Salamanca, Spain
| | - Miguel Vicente-Manzanares
- Molecular Mechanisms Program, Centro de Investigación del Cáncer/ Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC) and University of Salamanca, 37007 Salamanca, Spain.
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6
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Liu S, Marang C, Woodward M, Joumaa V, Leonard T, Scott B, Debold E, Herzog W, Walcott S. Modeling thick filament activation suggests a molecular basis for force depression. Biophys J 2024; 123:555-571. [PMID: 38291752 PMCID: PMC10938083 DOI: 10.1016/j.bpj.2024.01.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 12/05/2023] [Accepted: 01/22/2024] [Indexed: 02/01/2024] Open
Abstract
Multiscale models aiming to connect muscle's molecular and cellular function have been difficult to develop, in part due to a lack of self-consistent multiscale data. To address this gap, we measured the force response from single, skinned rabbit psoas muscle fibers to ramp shortenings and step stretches performed on the plateau region of the force-length relationship. We isolated myosin from the same muscles and, under similar conditions, performed single-molecule and ensemble measurements of myosin's ATP-dependent interaction with actin using laser trapping and in vitro motility assays. We fit the fiber data by developing a partial differential equation model that includes thick filament activation, whereby an increase in force on the thick filament pulls myosin out of an inhibited state. The model also includes a series elastic element and a parallel elastic element. This parallel elastic element models a titin-actin interaction proposed to account for the increase in isometric force after stretch (residual force enhancement). By optimizing the model fit to a subset of our fiber measurements, we specified seven unknown parameters. The model then successfully predicted the remainder of our fiber measurements and also our molecular measurements from the laser trap and in vitro motility. The success of the model suggests that our multiscale data are self-consistent and can serve as a testbed for other multiscale models. Moreover, the model captures the decrease in isometric force observed in our muscle fibers after active shortening (force depression), suggesting a molecular mechanism for force depression, whereby a parallel elastic element combines with thick filament activation to decrease the number of cycling cross-bridges.
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Affiliation(s)
- Shuyue Liu
- Faculty of Kinesiology, University of Calgary, Calgary, Alberta
| | - Chris Marang
- Department of Kinesiology, University of Massachusetts, Amherst, Massachusetts
| | - Mike Woodward
- Department of Kinesiology, University of Massachusetts, Amherst, Massachusetts
| | - Venus Joumaa
- Faculty of Kinesiology, University of Calgary, Calgary, Alberta
| | - Tim Leonard
- Faculty of Kinesiology, University of Calgary, Calgary, Alberta
| | - Brent Scott
- Department of Kinesiology, University of Massachusetts, Amherst, Massachusetts
| | - Edward Debold
- Department of Kinesiology, University of Massachusetts, Amherst, Massachusetts
| | - Walter Herzog
- Faculty of Kinesiology, University of Calgary, Calgary, Alberta
| | - Sam Walcott
- Mathematical Sciences, Bioinformatics and Computational Biology, Worcester Polytechnic Institute, Worcester, Massachusetts.
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7
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Wang C, Ding J, Wei Q, Du S, Gong X, Chew TG. Mechanosensitive accumulation of non-muscle myosin IIB during mitosis requires its translocation activity. iScience 2023; 26:107773. [PMID: 37720093 PMCID: PMC10504539 DOI: 10.1016/j.isci.2023.107773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 07/02/2023] [Accepted: 08/26/2023] [Indexed: 09/19/2023] Open
Abstract
Non-muscle myosin II (NMII) is a force-generating mechanosensitive enzyme that responds to mechanical forces. NMIIs mechanoaccumulate at the cell cortex in response to mechanical forces. It is essential for cells to mechanically adapt to the physical environment, failure of which results in mitotic defects when dividing in confined environment. Much less is known about how NMII mechanoaccumulation is regulated during mitosis. We show that mitotic cells respond to compressive stress by promoting accumulation of active RhoA at the cell cortex as in interphase cells. RhoA mechanoresponse during mitosis activates and stabilizes NMIIB via ROCK signaling, leading to NMIIB mechanoaccumulation at the cell cortex. Using disease-related myosin II mutations, we found that NMIIB mechanoaccumulation requires its motor activity that translocates actin filaments, but not just its actin-binding function. Thus, the motor activity coordinates structural movement and nucleotide state changes to fine-tune actin-binding affinity optimal for NMIIs to generate and respond to forces.
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Affiliation(s)
- Chao Wang
- Department of Cardiology of the Second Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang University, Hangzhou 310058, China
- The Zhejiang University-University of Edinburgh Institute, Zhejiang University School of Medicine, Zhejiang University, Haining 314400, China
| | - Jingjing Ding
- Department of Cardiology of the Second Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang University, Hangzhou 310058, China
- The Zhejiang University-University of Edinburgh Institute, Zhejiang University School of Medicine, Zhejiang University, Haining 314400, China
| | - Qiaodong Wei
- Department of Engineering Mechanics, School of Naval Architecture, Ocean and Civil Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Shoukang Du
- Department of Cardiology of the Second Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang University, Hangzhou 310058, China
- The Zhejiang University-University of Edinburgh Institute, Zhejiang University School of Medicine, Zhejiang University, Haining 314400, China
| | - Xiaobo Gong
- Department of Engineering Mechanics, School of Naval Architecture, Ocean and Civil Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Ting Gang Chew
- Department of Cardiology of the Second Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang University, Hangzhou 310058, China
- The Zhejiang University-University of Edinburgh Institute, Zhejiang University School of Medicine, Zhejiang University, Haining 314400, China
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8
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Liu S, Marang C, Woodward M, Joumaa V, Leonard T, Scott B, Debold E, Herzog W, Walcott S. Modeling Thick Filament Activation Suggests a Molecular Basis for Force Depression. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.27.559764. [PMID: 37808737 PMCID: PMC10557758 DOI: 10.1101/2023.09.27.559764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/10/2023]
Abstract
Multiscale models aiming to connect muscle's molecular and cellular function have been difficult to develop, in part, due to a lack of self-consistent multiscale data. To address this gap, we measured the force response from single skinned rabbit psoas muscle fibers to ramp shortenings and step stretches performed on the plateau region of the force-length relationship. We isolated myosin from the same muscles and, under similar conditions, performed single molecule and ensemble measurements of myosin's ATP-dependent interaction with actin using laser trapping and in vitro motility assays. We fit the fiber data by developing a partial differential equation model that includes thick filament activation, whereby an increase in force on the thick filament pulls myosin out of an inhibited state. The model also includes a series elastic element and a parallel elastic element. This parallel elastic element models a titin-actin interaction proposed to account for the increase in isometric force following stretch (residual force enhancement). By optimizing the model fit to a subset of our fiber measurements, we specified seven unknown parameters. The model then successfully predicted the remainder of our fiber measurements and also our molecular measurements from the laser trap and in vitro motility. The success of the model suggests that our multiscale data are self-consistent and can serve as a testbed for other multiscale models. Moreover, the model captures the decrease in isometric force observed in our muscle fibers after active shortening (force depression), suggesting a molecular mechanism for force depression, whereby a parallel elastic element combines with thick filament activation to decrease the number of cycling cross-bridges.
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Affiliation(s)
- Shuyue Liu
- Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
| | - Chris Marang
- Department of Kinesiology, University of Massachusetts, Amherst, Massachusetts, USA
| | - Mike Woodward
- Department of Kinesiology, University of Massachusetts, Amherst, Massachusetts, USA
| | - Venus Joumaa
- Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
| | - Tim Leonard
- Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
| | - Brent Scott
- Department of Kinesiology, University of Massachusetts, Amherst, Massachusetts, USA
| | - Edward Debold
- Department of Kinesiology, University of Massachusetts, Amherst, Massachusetts, USA
| | - Walter Herzog
- Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
| | - Sam Walcott
- Mathematical Sciences, Bioinformatics and Computational Biology, Worcester Polytechnic Institute, Worcester, Massachusetts, USA
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9
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Månsson A, Ušaj M, Moretto L, Matusovsky O, Velayuthan LP, Friedman R, Rassier DE. New paradigms in actomyosin energy transduction: Critical evaluation of non-traditional models for orthophosphate release. Bioessays 2023; 45:e2300040. [PMID: 37366639 DOI: 10.1002/bies.202300040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 05/30/2023] [Accepted: 06/01/2023] [Indexed: 06/28/2023]
Abstract
Release of the ATP hydrolysis product ortophosphate (Pi) from the active site of myosin is central in chemo-mechanical energy transduction and closely associated with the main force-generating structural change, the power-stroke. Despite intense investigations, the relative timing between Pi-release and the power-stroke remains poorly understood. This hampers in depth understanding of force production by myosin in health and disease and our understanding of myosin-active drugs. Since the 1990s and up to today, models that incorporate the Pi-release either distinctly before or after the power-stroke, in unbranched kinetic schemes, have dominated the literature. However, in recent years, alternative models have emerged to explain apparently contradictory findings. Here, we first compare and critically analyze three influential alternative models proposed previously. These are either characterized by a branched kinetic scheme or by partial uncoupling of Pi-release and the power-stroke. Finally, we suggest critical tests of the models aiming for a unified picture.
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Affiliation(s)
- Alf Månsson
- Department of Chemistry and Biomedical Sciences, Linnaeus University, Kalmar, Sweden
| | - Marko Ušaj
- Department of Chemistry and Biomedical Sciences, Linnaeus University, Kalmar, Sweden
| | - Luisa Moretto
- Department of Chemistry and Biomedical Sciences, Linnaeus University, Kalmar, Sweden
| | - Oleg Matusovsky
- Department of Kinesiology and Physical Education, McGill University, Montreal, Québec, Canada
| | - Lok Priya Velayuthan
- Department of Chemistry and Biomedical Sciences, Linnaeus University, Kalmar, Sweden
| | - Ran Friedman
- Department of Chemistry and Biomedical Sciences, Linnaeus University, Kalmar, Sweden
| | - Dilson E Rassier
- Department of Kinesiology and Physical Education, McGill University, Montreal, Québec, Canada
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10
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Bohmer M, Bhullar AS, Weitao T, Zhang L, Lee JH, Guo P. Revolving hexameric ATPases as asymmetric motors to translocate double-stranded DNA genome along one strand. iScience 2023; 26:106922. [PMID: 37305704 PMCID: PMC10250835 DOI: 10.1016/j.isci.2023.106922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023] Open
Abstract
DsDNA translocation through nanoscale pores is generally accomplished by ATPase biomotors. The discovery of the revolving dsDNA translocation mechanism, as opposed to rotation, in bacteriophage phi29 elucidated how ATPase motors move dsDNA. Revolution-driven, hexameric dsDNA motors have been reported in herpesvirus, bacterial FtsK, Streptomyces TraB, and T7 phage. This review explores the common relationship between their structure and mechanisms. Commonalities include moving along the 5'→3' strand, inchworm sequential action leading to an asymmetrical structure, channel chirality, channel size, and 3-step channel gating for controlling motion direction. The revolving mechanism and contact with one of the dsDNA strands addresses the historic controversy of dsDNA packaging using nicked, gapped, hybrid, or chemically modified DNA. These controversies surrounding dsDNA packaging activity using modified materials can be answered by whether the modification was introduced into the 3'→5' or 5'→3' strand. Perspectives concerning solutions to the controversy of motor structure and stoichiometry are also discussed.
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Affiliation(s)
- Margaret Bohmer
- Center for RNA Nanobiotechnology and Nanomedicine, The Ohio State University, Columbus, OH, USA
- College of Pharmacy, Division of Pharmaceutics and Pharmacology, The Ohio State University, Columbus, OH, USA
- College of Medicine, Dorothy M. Davis Heart and Lung Research Institute and James Comprehensive Cancer Center, The Ohio State University, Columbus, OH, USA
| | - Abhjeet S. Bhullar
- Center for RNA Nanobiotechnology and Nanomedicine, The Ohio State University, Columbus, OH, USA
- College of Pharmacy, Division of Pharmaceutics and Pharmacology, The Ohio State University, Columbus, OH, USA
- College of Medicine, Dorothy M. Davis Heart and Lung Research Institute and James Comprehensive Cancer Center, The Ohio State University, Columbus, OH, USA
- Interdisciplinary Biophysics Graduate Program, College of Art and Science, The Ohio State University, Columbus, OH 43210, USA
| | - Tao Weitao
- Center for the Genetics of Host Defense UT Southwestern Medical Center, Dallas, TX, USA
| | - Long Zhang
- Center for RNA Nanobiotechnology and Nanomedicine, The Ohio State University, Columbus, OH, USA
- College of Pharmacy, Division of Pharmaceutics and Pharmacology, The Ohio State University, Columbus, OH, USA
- College of Medicine, Dorothy M. Davis Heart and Lung Research Institute and James Comprehensive Cancer Center, The Ohio State University, Columbus, OH, USA
| | - Jing-Huei Lee
- Department of Biomedical Engineering, College of Engineering and Applied Science, University of Cincinnati, Cincinnati, OH, USA
| | - Peixuan Guo
- Center for RNA Nanobiotechnology and Nanomedicine, The Ohio State University, Columbus, OH, USA
- College of Pharmacy, Division of Pharmaceutics and Pharmacology, The Ohio State University, Columbus, OH, USA
- College of Medicine, Dorothy M. Davis Heart and Lung Research Institute and James Comprehensive Cancer Center, The Ohio State University, Columbus, OH, USA
- Interdisciplinary Biophysics Graduate Program, College of Art and Science, The Ohio State University, Columbus, OH 43210, USA
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11
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Marang C, Scott B, Chambers J, Gunther LK, Yengo CM, Debold EP. A mutation in switch I alters the load-dependent kinetics of myosin Va. Nat Commun 2023; 14:3137. [PMID: 37253724 PMCID: PMC10229639 DOI: 10.1038/s41467-023-38535-0] [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: 09/19/2022] [Accepted: 05/05/2023] [Indexed: 06/01/2023] Open
Abstract
Myosin Va is the molecular motor that drives intracellular vesicular transport, powered by the transduction of chemical energy from ATP into mechanical work. The coupling of the powerstroke and phosphate (Pi) release is key to understanding the transduction process, and crucial details of this process remain unclear. Therefore, we determined the effect of elevated Pi on the force-generating capacity of a mini-ensemble of myosin Va S1 (WT) in a laser trap assay. By increasing the stiffness of the laser trap we determined the effect of increasing resistive loads on the rate of Pi-induced detachment from actin, and quantified this effect using the Bell approximation. We observed that WT myosin generated higher forces and larger displacements at the higher laser trap stiffnesses in the presence of 30 mM Pi, but binding event lifetimes decreased dramatically, which is most consistent with the powerstroke preceding the release of Pi from the active site. Repeating these experiments using a construct with a mutation in switch I of the active site (S217A) caused a seven-fold increase in the load-dependence of the Pi-induced detachment rate, suggesting that the S217A region of switch I may help mediate the load-dependence of Pi-rebinding.
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Affiliation(s)
- Christopher Marang
- Department of Kinesiology, University of Massachusetts, Amherst, MA, 01003, USA
| | - Brent Scott
- Department of Kinesiology, University of Massachusetts, Amherst, MA, 01003, USA
| | - James Chambers
- Institute for Applied Life Sciences, University of Massachusetts, Amherst, MA, 01003, USA
| | - Laura K Gunther
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, PA, 17033, USA
| | - Christopher M Yengo
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, PA, 17033, USA
| | - Edward P Debold
- Department of Kinesiology, University of Massachusetts, Amherst, MA, 01003, USA.
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12
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Opportunities and Challenges for the Development of MRCK Kinases Inhibitors as Potential Cancer Chemotherapeutics. Cells 2023; 12:cells12040534. [PMID: 36831201 PMCID: PMC9954052 DOI: 10.3390/cells12040534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 01/31/2023] [Accepted: 02/01/2023] [Indexed: 02/10/2023] Open
Abstract
Cytoskeleton organization and dynamics are rapidly regulated by post-translational modifications of key target proteins. Acting downstream of the Cdc42 GTPase, the myotonic dystrophy-related Cdc42-binding kinases MRCKα, MRCKβ, and MRCKγ have recently emerged as important players in cytoskeleton regulation through the phosphorylation of proteins such as the regulatory myosin light chain proteins. Compared with the closely related Rho-associated coiled-coil kinases 1 and 2 (ROCK1 and ROCK2), the contributions of the MRCK kinases are less well characterized, one reason for this being that the discovery of potent and selective MRCK pharmacological inhibitors occurred many years after the discovery of ROCK inhibitors. The disclosure of inhibitors, such as BDP5290 and BDP9066, that have marked selectivity for MRCK over ROCK, as well as the dual ROCK + MRCK inhibitor DJ4, has expanded the repertoire of chemical biology tools to study MRCK function in normal and pathological conditions. Recent research has used these novel inhibitors to establish the role of MRCK signalling in epithelial polarization, phagocytosis, cytoskeleton organization, cell motility, and cancer cell invasiveness. Furthermore, pharmacological MRCK inhibition has been shown to elicit therapeutically beneficial effects in cell-based and in vivo studies of glioma, skin, and ovarian cancers.
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Doran MH, Rynkiewicz MJ, Rassici D, Bodt SM, Barry ME, Bullitt E, Yengo CM, Moore JR, Lehman W. Conformational changes linked to ADP release from human cardiac myosin bound to actin-tropomyosin. J Gen Physiol 2023; 155:213802. [PMID: 36633586 PMCID: PMC9859928 DOI: 10.1085/jgp.202213267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 11/11/2022] [Accepted: 12/14/2022] [Indexed: 01/13/2023] Open
Abstract
Following binding to the thin filament, β-cardiac myosin couples ATP-hydrolysis to conformational rearrangements in the myosin motor that drive myofilament sliding and cardiac ventricular contraction. However, key features of the cardiac-specific actin-myosin interaction remain uncertain, including the structural effect of ADP release from myosin, which is rate-limiting during force generation. In fact, ADP release slows under experimental load or in the intact heart due to the afterload, thereby adjusting cardiac muscle power output to meet physiological demands. To further elucidate the structural basis of this fundamental process, we used a combination of cryo-EM reconstruction methodologies to determine structures of the human cardiac actin-myosin-tropomyosin filament complex at better than 3.4 Å-resolution in the presence and in the absence of Mg2+·ADP. Focused refinements of the myosin motor head and its essential light chains in these reconstructions reveal that small changes in the nucleotide-binding site are coupled to significant rigid body movements of the myosin converter domain and a 16-degree lever arm swing. Our structures provide a mechanistic framework to understand the effect of ADP binding and release on human cardiac β-myosin, and offer insights into the force-sensing mechanism displayed by the cardiac myosin motor.
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Affiliation(s)
- Matthew H. Doran
- School of Medicine, Department of Physiology and Biophysics, Boston University, Boston, MA, USA,Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Michael J. Rynkiewicz
- School of Medicine, Department of Physiology and Biophysics, Boston University, Boston, MA, USA
| | - David Rassici
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, PA, USA
| | - Skylar M.L. Bodt
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, PA, USA
| | - Meaghan E. Barry
- Department of Biological Science, University of Massachusetts Lowell, Lowell, MA, USA
| | - Esther Bullitt
- School of Medicine, Department of Physiology and Biophysics, Boston University, Boston, MA, USA
| | - Christopher M. Yengo
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, PA, USA
| | - Jeffrey R. Moore
- Department of Biological Science, University of Massachusetts Lowell, Lowell, MA, USA
| | - William Lehman
- School of Medicine, Department of Physiology and Biophysics, Boston University, Boston, MA, USA
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McMillan SN, Scarff CA. Cryo-electron microscopy analysis of myosin at work and at rest. Curr Opin Struct Biol 2022; 75:102391. [DOI: 10.1016/j.sbi.2022.102391] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2022] [Revised: 04/18/2022] [Accepted: 04/22/2022] [Indexed: 01/01/2023]
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