1
|
dos Santos Á, Fili N, Hari-Gupta Y, Gough RE, Wang L, Martin-Fernandez M, Aaron J, Wait E, Chew TL, Toseland CP. Binding partners regulate unfolding of myosin VI to activate the molecular motor. Biochem J 2022; 479:1409-1428. [PMID: 35722941 PMCID: PMC9342898 DOI: 10.1042/bcj20220025] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 06/15/2022] [Accepted: 06/20/2022] [Indexed: 11/22/2022]
Abstract
Myosin VI is the only minus-end actin motor and it is coupled to various cellular processes ranging from endocytosis to transcription. This multi-potent nature is achieved through alternative isoform splicing and interactions with a network of binding partners. There is a complex interplay between isoforms and binding partners to regulate myosin VI. Here, we have compared the regulation of two myosin VI splice isoforms by two different binding partners. By combining biochemical and single-molecule approaches, we propose that myosin VI regulation follows a generic mechanism, independently of the spliced isoform and the binding partner involved. We describe how myosin VI adopts an autoinhibited backfolded state which is released by binding partners. This unfolding activates the motor, enhances actin binding and can subsequently trigger dimerization. We have further expanded our study by using single-molecule imaging to investigate the impact of binding partners upon myosin VI molecular organization and dynamics.
Collapse
Affiliation(s)
- Ália dos Santos
- Department of Oncology and Metabolism, University of Sheffield, Sheffield S10 2RX, U.K
| | - Natalia Fili
- Department of Oncology and Metabolism, University of Sheffield, Sheffield S10 2RX, U.K
| | - Yukti Hari-Gupta
- School of Biosciences, University of Kent, Canterbury CT2 7NJ, U.K
| | - Rosemarie E. Gough
- Department of Oncology and Metabolism, University of Sheffield, Sheffield S10 2RX, U.K
| | - Lin Wang
- Central Laser Facility, Research Complex at Harwell, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell, Didcot, Oxford OX11 0QX, U.K
| | - Marisa Martin-Fernandez
- Central Laser Facility, Research Complex at Harwell, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell, Didcot, Oxford OX11 0QX, U.K
| | - Jesse Aaron
- Advanced Imaging Center, HHMI Janelia Research Campus, Ashburn, U.S.A
| | - Eric Wait
- Advanced Imaging Center, HHMI Janelia Research Campus, Ashburn, U.S.A
| | - Teng-Leong Chew
- Advanced Imaging Center, HHMI Janelia Research Campus, Ashburn, U.S.A
| | | |
Collapse
|
2
|
Wu Y, Zhang Y, Xu X, Wang W. Effect of Ca 2+ binding states of calmodulin on the conformational dynamics and force responses of myosin lever arm. J Chem Phys 2022; 157:035101. [DOI: 10.1063/5.0095842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The mechanochemical coupling and biological function of myosin motors are regulated by Ca2+ concentrations. As one of the regulation pathways, Ca2+ binding induces conformational change of the light chain calmodulin and its binding modes with myosin lever arm, which can affect the stiffness of the lever arm and force transmission. However, the underlying molecular mechanism of the Ca2+ regulated stiffness change is not fully understood. Here we study the effect of Ca2+ binding on the conformational dynamics and stiffness of the myosin VIIa lever arm bound with calmodulin by performing molecular dynamics simulations and dynamic correlation network analysis. The results showed that the calmodulin bound lever arm at apo state can sample three different conformations. In addition to the conformation observed in crystal structure, calmodulin bound lever arm at apo condition can also adopt another two conformations featured by different extents of small-angle bending of the lever arm. However, large-angle bending is strongly prohibited. Such results suggest that the calmodulin bound lever arm without Ca2+ binding is plastic for small-angle deformation but shows high stiffness for large-angle deformation. In comparison, after the binding of Ca2+, although the calmodulin bound lever arm is locally more rigid, it can adopt largely deformed or even unfolded conformations, which may render the lever arm incompetent for force transmission. The conformational plasticity of the lever arm for small-angle deformation at apo condition may be utilized as force buffer to prevent the lever arm from unfolding during the power stroke action of the motor domain.
Collapse
Affiliation(s)
- Yichao Wu
- Department of Physics, Nanjing University, China
| | | | | | - Wei Wang
- Department of Physics, Nanjing University, China
| |
Collapse
|
3
|
Mier P, Paladin L, Tamana S, Petrosian S, Hajdu-Soltész B, Urbanek A, Gruca A, Plewczynski D, Grynberg M, Bernadó P, Gáspári Z, Ouzounis CA, Promponas VJ, Kajava AV, Hancock JM, Tosatto SCE, Dosztanyi Z, Andrade-Navarro MA. Disentangling the complexity of low complexity proteins. Brief Bioinform 2021; 21:458-472. [PMID: 30698641 PMCID: PMC7299295 DOI: 10.1093/bib/bbz007] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Revised: 12/19/2018] [Accepted: 01/07/2019] [Indexed: 12/31/2022] Open
Abstract
There are multiple definitions for low complexity regions (LCRs) in protein sequences, with all of them broadly considering LCRs as regions with fewer amino acid types compared to an average composition. Following this view, LCRs can also be defined as regions showing composition bias. In this critical review, we focus on the definition of sequence complexity of LCRs and their connection with structure. We present statistics and methodological approaches that measure low complexity (LC) and related sequence properties. Composition bias is often associated with LC and disorder, but repeats, while compositionally biased, might also induce ordered structures. We illustrate this dichotomy, and more generally the overlaps between different properties related to LCRs, using examples. We argue that statistical measures alone cannot capture all structural aspects of LCRs and recommend the combined usage of a variety of predictive tools and measurements. While the methodologies available to study LCRs are already very advanced, we foresee that a more comprehensive annotation of sequences in the databases will enable the improvement of predictions and a better understanding of the evolution and the connection between structure and function of LCRs. This will require the use of standards for the generation and exchange of data describing all aspects of LCRs. Short abstract There are multiple definitions for low complexity regions (LCRs) in protein sequences. In this critical review, we focus on the definition of sequence complexity of LCRs and their connection with structure. We present statistics and methodological approaches that measure low complexity (LC) and related sequence properties. Composition bias is often associated with LC and disorder, but repeats, while compositionally biased, might also induce ordered structures. We illustrate this dichotomy, plus overlaps between different properties related to LCRs, using examples.
Collapse
Affiliation(s)
- Pablo Mier
- Institute of Organismic and Molecular Evolution, Johannes Gutenberg University of Mainz, Mainz, Germany
| | - Lisanna Paladin
- Department of Biomedical Science, University of Padova, Padova, Italy
| | - Stella Tamana
- Bioinformatics Research Laboratory, Department of Biological Sciences, University of Cyprus, Nicosia, Cyprus
| | - Sophia Petrosian
- Biological Computation and Process Laboratory, Chemical Process & Energy Resources Institute, Centre for Research & Technology Hellas, Thessalonica, Greece
| | - Borbála Hajdu-Soltész
- MTA-ELTE Lendület Bioinformatics Research Group, Department of Biochemistry, Eötvös Loránd University, Budapest, Hungary
| | - Annika Urbanek
- Centre de Biochimie Structurale, INSERM, CNRS, Université de Montpellier, Montpellier, France
| | - Aleksandra Gruca
- Institute of Informatics, Silesian University of Technology, Gliwice, Poland
| | - Dariusz Plewczynski
- Center of New Technologies, University of Warsaw, Warsaw, Poland.,Faculty of Mathematics and Information Science, Warsaw University of Technology, Warsaw, Poland
| | | | - Pau Bernadó
- Centre de Biochimie Structurale, INSERM, CNRS, Université de Montpellier, Montpellier, France
| | - Zoltán Gáspári
- Faculty of Information Technology and Bionics, Pázmány Péter Catholic University, Budapest, Hungary
| | - Christos A Ouzounis
- Biological Computation and Process Laboratory, Chemical Process & Energy Resources Institute, Centre for Research & Technology Hellas, Thessalonica, Greece
| | - Vasilis J Promponas
- Bioinformatics Research Laboratory, Department of Biological Sciences, University of Cyprus, Nicosia, Cyprus
| | - Andrey V Kajava
- Centre de Recherche en Biologie Cellulaire de Montpellier, CNRS-UMR, Institut de Biologie Computationnelle, Universite de Montpellier, Montpellier, France.,Institute of Bioengineering, University ITMO, St. Petersburg, Russia
| | - John M Hancock
- Earlham Institute, Norwich, UK.,ELIXIR Hub, Welcome Genome Campus, Hinxton, UK
| | - Silvio C E Tosatto
- Department of Biomedical Science, University of Padova, Padova, Italy.,CNR Institute of Neuroscience, Padova, Italy
| | - Zsuzsanna Dosztanyi
- MTA-ELTE Lendület Bioinformatics Research Group, Department of Biochemistry, Eötvös Loránd University, Budapest, Hungary
| | - Miguel A Andrade-Navarro
- Institute of Organismic and Molecular Evolution, Johannes Gutenberg University of Mainz, Mainz, Germany
| |
Collapse
|
4
|
Pillon M, Doublet P. Myosins, an Underestimated Player in the Infectious Cycle of Pathogenic Bacteria. Int J Mol Sci 2021; 22:ijms22020615. [PMID: 33435466 PMCID: PMC7826972 DOI: 10.3390/ijms22020615] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 01/04/2021] [Accepted: 01/06/2021] [Indexed: 12/15/2022] Open
Abstract
Myosins play a key role in many cellular processes such as cell migration, adhesion, intracellular trafficking and internalization processes, making them ideal targets for bacteria. Through selected examples, such as enteropathogenic E. coli (EPEC), Neisseria, Salmonella, Shigella, Listeria or Chlamydia, this review aims to illustrate how bacteria target and hijack host cell myosins in order to adhere to the cell, to enter the cell by triggering their internalization, to evade from the cytosolic autonomous cell defense, to promote the biogenesis of intracellular replicative niche, to disseminate in tissues by cell-to-cell spreading, to exit out the host cell, and also to evade from macrophage phagocytosis. It highlights the diversity and sophistication of the strategy evolved by bacteria to manipulate one of their privileged targets, the actin cytoskeleton.
Collapse
Affiliation(s)
- Margaux Pillon
- CIRI, Centre International de Recherche en Infectiologie, Legionella Pathogenesis Group, Université de Lyon, 69007 Lyon, France;
- Institut National de la Santé et de la Recherche Médicale (INSERM), U1111, 69007 Lyon, France
- Ecole Normale Supérieure de Lyon, 69007 Lyon, France
- Centre International de Recherche en Infectiologie, Université Claude Bernard Lyon 1, 69007 Lyon, France
- Centre National de la Recherche Scientifique, UMR5308, 69007 Lyon, France
| | - Patricia Doublet
- CIRI, Centre International de Recherche en Infectiologie, Legionella Pathogenesis Group, Université de Lyon, 69007 Lyon, France;
- Institut National de la Santé et de la Recherche Médicale (INSERM), U1111, 69007 Lyon, France
- Ecole Normale Supérieure de Lyon, 69007 Lyon, France
- Centre International de Recherche en Infectiologie, Université Claude Bernard Lyon 1, 69007 Lyon, France
- Centre National de la Recherche Scientifique, UMR5308, 69007 Lyon, France
- Correspondence:
| |
Collapse
|
5
|
Gupte TM, Ritt M, Sivaramakrishnan S. ER/K-link-Leveraging a native protein linker to probe dynamic cellular interactions. Methods Enzymol 2020; 647:173-208. [PMID: 33482988 PMCID: PMC8009693 DOI: 10.1016/bs.mie.2020.10.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
ER/K α-helices are a subset of single alpha helical domains, which exhibit unusual stability as isolated protein secondary structures. They adopt an elongated structural conformation, while regulating the frequency of interactions between proteins or polypeptides fused to their ends. Here we review recent advances on the structure, stability and function of ER/K α-helices as linkers (ER/K linkers) in native proteins. We describe methodological considerations in the molecular cloning, protein expression and measurement of interaction strengths, using sensors incorporating ER/K linkers. We highlight biological insights obtained over the last decade by leveraging distinct biophysical features of ER/K-linked sensors. We conclude with the outlook for the use of ER/K linkers in the selective modulation of dynamic cellular interactions.
Collapse
Affiliation(s)
- Tejas M Gupte
- Department of Genetics, Cell Biology, and Development, College of Biological Sciences, University of Minnesota, Minneapolis, MN, United States
| | - Michael Ritt
- Department of Genetics, Cell Biology, and Development, College of Biological Sciences, University of Minnesota, Minneapolis, MN, United States
| | - Sivaraj Sivaramakrishnan
- Department of Genetics, Cell Biology, and Development, College of Biological Sciences, University of Minnesota, Minneapolis, MN, United States.
| |
Collapse
|
6
|
Abstract
Myosins constitute a superfamily of actin-based molecular motor proteins that mediates a variety of cellular activities including muscle contraction, cell migration, intracellular transport, the formation of membrane projections, cell adhesion, and cell signaling. The 12 myosin classes that are expressed in humans share sequence similarities especially in the N-terminal motor domain; however, their enzymatic activities, regulation, ability to dimerize, binding partners, and cellular functions differ. It is becoming increasingly apparent that defects in myosins are associated with diseases including cardiomyopathies, colitis, glomerulosclerosis, neurological defects, cancer, blindness, and deafness. Here, we review the current state of knowledge regarding myosins and disease.
Collapse
|
7
|
|
8
|
Barnes CA, Shen Y, Ying J, Bax A. Modulating the Stiffness of the Myosin VI Single α-Helical Domain. Biophys J 2020; 118:1119-1128. [PMID: 32049057 DOI: 10.1016/j.bpj.2020.01.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 12/20/2019] [Accepted: 01/02/2020] [Indexed: 11/28/2022] Open
Abstract
Highly charged, single α-helical (SAH) domains contain a high percentage of Arg, Lys, and Glu residues. Their dynamic salt bridge pairing creates the exceptional stiffness of these helical rods, with a persistence length of more than 200 Å for the myosin VI SAH domain. With the aim of modulating the stiffness of the helical structure, we investigated the effect, using NMR spectroscopy, of substituting key charged Arg, Lys, Glu, and Asp residues by Gly or His. Results indicate that such mutations result in the transient breaking of the helix at the site of mutation but with noticeable impact on amide hydrogen exchange rates extending as far as ±2 helical turns, pointing to a substantial degree of cooperativity in SAH stability. Whereas a single Gly substitution caused transient breaks ∼20% of the time, two consecutive Gly substitutions break the helix ∼65% of the time. NMR relaxation measurements indicate that the exchange rate between an intact and a broken helix is fast (>300,000 s-1) and that for the wild-type sequence, the finite persistence length is dominated by thermal fluctuations of backbone torsion angles and H-bond lengths, not by transient helix breaking. The double mutation D27H/E28H causes a pH-dependent fraction of helix disruption, in which the helix breakage increases from 26% at pH 7.5 to 53% at pH 5.5. The ability to modulate helical integrity by pH may enable incorporation of externally tunable dynamic components in the design of molecular machines.
Collapse
Affiliation(s)
- C Ashley Barnes
- Laboratory of Chemical Physics, NIDDK, National Institutes of Health, Bethesda, Maryland
| | - Yang Shen
- Laboratory of Chemical Physics, NIDDK, National Institutes of Health, Bethesda, Maryland
| | - Jinfa Ying
- Laboratory of Chemical Physics, NIDDK, National Institutes of Health, Bethesda, Maryland
| | - Ad Bax
- Laboratory of Chemical Physics, NIDDK, National Institutes of Health, Bethesda, Maryland.
| |
Collapse
|
9
|
Sellers JR, Takagi Y. How Myosin 5 Walks Deduced from Single-Molecule Biophysical Approaches. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1239:153-181. [PMID: 32451859 DOI: 10.1007/978-3-030-38062-5_8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Myosin 5a is a two-headed myosin that functions as a cargo transporter in cells. To accomplish this task it has evolved several unique structural and kinetic features that allow it to move processively as a single molecule along actin filaments. A plethora of biophysical techniques have been used to elucidate the detailed mechanism of its movement along actin filaments in vitro. This chapter describes how this mechanism was deduced.
Collapse
Affiliation(s)
- James R Sellers
- Laboratory of Molecular Physiology, Cell and Developmental Biology Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA.
| | - Yasuharu Takagi
- Laboratory of Molecular Physiology, Cell and Developmental Biology Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| |
Collapse
|
10
|
Unconventional Myosins: How Regulation Meets Function. Int J Mol Sci 2019; 21:ijms21010067. [PMID: 31861842 PMCID: PMC6981383 DOI: 10.3390/ijms21010067] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 12/16/2019] [Accepted: 12/18/2019] [Indexed: 01/24/2023] Open
Abstract
Unconventional myosins are multi-potent molecular motors that are assigned important roles in fundamental cellular processes. Depending on their mechano-enzymatic properties and structural features, myosins fulfil their roles by acting as cargo transporters along the actin cytoskeleton, molecular anchors or tension sensors. In order to perform such a wide range of roles and modes of action, myosins need to be under tight regulation in time and space. This is achieved at multiple levels through diverse regulatory mechanisms: the alternative splicing of various isoforms, the interaction with their binding partners, their phosphorylation, their applied load and the composition of their local environment, such as ions and lipids. This review summarizes our current knowledge of how unconventional myosins are regulated, how these regulatory mechanisms can adapt to the specific features of a myosin and how they can converge with each other in order to ensure the required tight control of their function.
Collapse
|
11
|
Frisbie CP, Lushnikov AY, Krasnoslobodtsev AV, Riethoven JJM, Clarke JL, Stepchenkova EI, Petrosyan A. Post-ER Stress Biogenesis of Golgi Is Governed by Giantin. Cells 2019; 8:E1631. [PMID: 31847122 PMCID: PMC6953117 DOI: 10.3390/cells8121631] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 12/05/2019] [Accepted: 12/09/2019] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND The Golgi apparatus undergoes disorganization in response to stress, but it is able to restore compact and perinuclear structure under recovery. This self-organization mechanism is significant for cellular homeostasis, but remains mostly elusive, as does the role of giantin, the largest Golgi matrix dimeric protein. METHODS In HeLa and different prostate cancer cells, we used the model of cellular stress induced by Brefeldin A (BFA). The conformational structure of giantin was assessed by proximity ligation assay and atomic force microscopy. The post-BFA distribution of Golgi resident enzymes was examined by 3D SIM high-resolution microscopy. RESULTS We detected that giantin is rather flexible than an extended coiled-coil dimer and BFA-induced Golgi disassembly was associated with giantin monomerization. A fusion of the nascent Golgi membranes after BFA washout is forced by giantin re-dimerization via disulfide bond in its luminal domain and assisted by Rab6a GTPase. GM130-GRASP65-dependent enzymes are able to reach the nascent Golgi membranes, while giantin-sensitive enzymes appeared at the Golgi after its complete recovery via direct interaction of their cytoplasmic tail with N-terminus of giantin. CONCLUSION Post-stress recovery of Golgi is conducted by giantin dimer and Golgi proteins refill membranes according to their docking affiliation rather than their intra-Golgi location.
Collapse
Affiliation(s)
- Cole P. Frisbie
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198-5870, USA;
| | - Alexander Y. Lushnikov
- Nanoimaging Core Facility, University of Nebraska Medical Center, Omaha, NE 68198-6025, USA; (A.Y.L.); (A.V.K.)
| | - Alexey V. Krasnoslobodtsev
- Nanoimaging Core Facility, University of Nebraska Medical Center, Omaha, NE 68198-6025, USA; (A.Y.L.); (A.V.K.)
- Department of Physics, University of Nebraska-Omaha, Omaha, NE 68182-0266, USA
| | - Jean-Jack M. Riethoven
- Center for Biotechnology, University of Nebraska-Lincoln, Lincoln, NE 68588-0665, USA;
- The Nebraska Center for Integrated Biomolecular Communication, University of Nebraska-Lincoln, Lincoln, NE 68588-0304, USA;
| | - Jennifer L. Clarke
- The Nebraska Center for Integrated Biomolecular Communication, University of Nebraska-Lincoln, Lincoln, NE 68588-0304, USA;
- Department of Statistics, University of Nebraska-Lincoln, Lincoln, NE 68583-0963, USA
| | - Elena I. Stepchenkova
- Vavilov Institute of General Genetics, Saint-Petersburg Branch, Russian Academy of Sciences, Saint-Petersburg 199034, Russia;
- Department of Genetics, Saint-Petersburg State University, Saint-Petersburg 199034, Russia
| | - Armen Petrosyan
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198-5870, USA;
- The Nebraska Center for Integrated Biomolecular Communication, University of Nebraska-Lincoln, Lincoln, NE 68588-0304, USA;
- The Fred and Pamela Buffett Cancer Center, Omaha, NE 68198-5870, USA
| |
Collapse
|
12
|
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.
Collapse
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
| |
Collapse
|
13
|
Optimized filopodia formation requires myosin tail domain cooperation. Proc Natl Acad Sci U S A 2019; 116:22196-22204. [PMID: 31611382 DOI: 10.1073/pnas.1901527116] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Filopodia are actin-filled protrusions employed by cells to interact with their environment. Filopodia formation in Amoebozoa and Metazoa requires the phylogenetically diverse MyTH4-FERM (MF) myosins DdMyo7 and Myo10, respectively. While Myo10 is known to form antiparallel dimers, DdMyo7 lacks a coiled-coil domain in its proximal tail region, raising the question of how such divergent motors perform the same function. Here, it is shown that the DdMyo7 lever arm plays a role in both autoinhibition and function while the proximal tail region can mediate weak dimerization, and is proposed to be working in cooperation with the C-terminal MF domain to promote partner-mediated dimerization. Additionally, a forced dimer of the DdMyo7 motor is found to weakly rescue filopodia formation, further highlighting the importance of the C-terminal MF domain. Thus, weak dimerization activity of the DdMyo7 proximal tail allows for sensitive regulation of myosin activity to prevent inappropriate activation of filopodia formation. The results reveal that the principles of MF myosin-based filopodia formation are conserved via divergent mechanisms for dimerization.
Collapse
|
14
|
Barnes CA, Shen Y, Ying J, Takagi Y, Torchia DA, Sellers JR, Bax A. Remarkable Rigidity of the Single α-Helical Domain of Myosin-VI As Revealed by NMR Spectroscopy. J Am Chem Soc 2019; 141:9004-9017. [PMID: 31117653 PMCID: PMC6556874 DOI: 10.1021/jacs.9b03116] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Indexed: 11/29/2022]
Abstract
Although the α-helix has long been recognized as an all-important element of secondary structure, it generally requires stabilization by tertiary interactions with other parts of a protein's structure. Highly charged single α-helical (SAH) domains, consisting of a high percentage (>75%) of Arg, Lys, and Glu residues, are exceptions to this rule but have been difficult to characterize structurally. Our study focuses on the 68-residue medial tail domain of myosin-VI, which is found to contain a highly ordered α-helical structure extending from Glu-6 to Lys-63. High hydrogen exchange protection factors (15-150), small (ca. 4 Hz) 3 JHNHα couplings, and a near-perfect fit to an ideal model α-helix for its residual dipolar couplings (RDCs), measured in a filamentous phage medium, support the high regularity of this helix. Remarkably, the hydrogen exchange rates are far more homogeneous than the protection factors derived from them, suggesting that for these transiently broken helices the intrinsic exchange rates derived from the amino acid sequence are not appropriate reference values. 15N relaxation data indicate a very high degree of rotational diffusion anisotropy ( D∥/ D⊥ ≈ 7.6), consistent with the hydrodynamic behavior predicted for such a long, nearly straight α-helix. Alignment of the helix by a paramagnetic lanthanide ion attached to its N-terminal region shows a decrease in alignment as the distance from the tagging site increases. This decrease yields a precise measure for the persistence length of 224 ± 10 Å at 20 °C, supporting the idea that the role of the SAH helix is to act as an extension of the myosin-VI lever arm.
Collapse
|
15
|
Michie KA, Bermeister A, Robertson NO, Goodchild SC, Curmi PMG. Two Sides of the Coin: Ezrin/Radixin/Moesin and Merlin Control Membrane Structure and Contact Inhibition. Int J Mol Sci 2019; 20:ijms20081996. [PMID: 31018575 PMCID: PMC6515277 DOI: 10.3390/ijms20081996] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 04/16/2019] [Accepted: 04/19/2019] [Indexed: 12/21/2022] Open
Abstract
The merlin-ERM (ezrin, radixin, moesin) family of proteins plays a central role in linking the cellular membranes to the cortical actin cytoskeleton. Merlin regulates contact inhibition and is an integral part of cell–cell junctions, while ERM proteins, ezrin, radixin and moesin, assist in the formation and maintenance of specialized plasma membrane structures and membrane vesicle structures. These two protein families share a common evolutionary history, having arisen and separated via gene duplication near the origin of metazoa. During approximately 0.5 billion years of evolution, the merlin and ERM family proteins have maintained both sequence and structural conservation to an extraordinary level. Comparing crystal structures of merlin-ERM proteins and their complexes, a picture emerges of the merlin-ERM proteins acting as switchable interaction hubs, assembling protein complexes on cellular membranes and linking them to the actin cytoskeleton. Given the high level of structural conservation between the merlin and ERM family proteins we speculate that they may function together.
Collapse
Affiliation(s)
- Katharine A Michie
- School of Physics, University of New South Wales, Sydney 2052, Australia.
| | - Adam Bermeister
- School of Physics, University of New South Wales, Sydney 2052, Australia.
| | - Neil O Robertson
- School of Physics, University of New South Wales, Sydney 2052, Australia.
| | - Sophia C Goodchild
- Department of Molecular Sciences, Macquarie University, Sydney 2109, Australia.
| | - Paul M G Curmi
- School of Physics, University of New South Wales, Sydney 2052, Australia.
| |
Collapse
|
16
|
Batchelor M, Wolny M, Baker EG, Paci E, Kalverda AP, Peckham M. Dynamic ion pair behavior stabilizes single α-helices in proteins. J Biol Chem 2019; 294:3219-3234. [PMID: 30593502 PMCID: PMC6398138 DOI: 10.1074/jbc.ra118.006752] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 12/17/2018] [Indexed: 11/06/2022] Open
Abstract
Ion pairs are key stabilizing interactions between oppositely charged amino acid side chains in proteins. They are often depicted as single conformer salt bridges (hydrogen-bonded ion pairs) in crystal structures, but it is unclear how dynamic they are in solution. Ion pairs are thought to be particularly important in stabilizing single α-helix (SAH) domains in solution. These highly stable domains are rich in charged residues (such as Arg, Lys, and Glu) with potential ion pairs across adjacent turns of the helix. They provide a good model system to investigate how ion pairs can contribute to protein stability. Using NMR spectroscopy, small-angle X-ray light scattering (SAXS), and molecular dynamics simulations, we provide here experimental evidence that ion pairs exist in a SAH in murine myosin 7a (residues 858-935), but that they are not fixed or long lasting. In silico modeling revealed that the ion pairs within this α-helix exhibit dynamic behavior, rapidly forming and breaking and alternating between different partner residues. The low-energy helical state was compatible with a great variety of ion pair combinations. Flexible ion pair formation utilizing a subset of those available at any one time avoided the entropic penalty of fixing side chain conformations, which likely contributed to helix stability overall. These results indicate the dynamic nature of ion pairs in SAHs. More broadly, thermodynamic stability in other proteins is likely to benefit from the dynamic behavior of multi-option solvent-exposed ion pairs.
Collapse
Affiliation(s)
- Matthew Batchelor
- From the School of Molecular and Cellular Biology and the Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom and
| | - Marcin Wolny
- From the School of Molecular and Cellular Biology and the Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom and
| | - Emily G Baker
- the School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, United Kingdom
| | - Emanuele Paci
- From the School of Molecular and Cellular Biology and the Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom and
| | - Arnout P Kalverda
- From the School of Molecular and Cellular Biology and the Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom and
| | - Michelle Peckham
- From the School of Molecular and Cellular Biology and the Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom and
| |
Collapse
|
17
|
Batchelor M, Paci E. Helical Polyampholyte Sequences Have Unique Thermodynamic Properties. J Phys Chem B 2018; 122:11784-11791. [PMID: 30351106 DOI: 10.1021/acs.jpcb.8b08344] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Helices are the most common structural pattern observed in structured proteins. Polypeptide sequences that form helices in isolation have been identified and extensively studied. These are generally rich in alanine, the amino acid with strongest helical propensity. Insertion of charged or polar amino acids has been shown to be necessary to make alanine-rich peptides soluble and sometimes even increase the helicity of the peptides. More recently sequences that contain mostly charged residues (E-R/K rich) have been found in naturally occurring proteins that are highly helical, soluble, and extended regardless their length. Artificial sequences composed mostly or exclusively of charged amino acids have been designed that are also highly helical, depending on the specific pattern of oppositely charged residues. Here we explore the thermodynamic properties of a number of 16-residue long peptides with varying helical propensity by performing equilibrium simulations over a broad range of temperatures. We observe quantitative differences in the peptides' helical propensities that can be related to qualitative differences in the free energy landscape, depending on the ampholytic patterns in the sequence. The results provide hints on how the specific physical properties of naturally occurring long sequences with similar patterns of charged residues may relate to their biological function.
Collapse
Affiliation(s)
- Matthew Batchelor
- Astbury Centre for Structural Molecular Biology , University of Leeds , Leeds LS2 9JT , U.K
| | - Emanuele Paci
- Astbury Centre for Structural Molecular Biology , University of Leeds , Leeds LS2 9JT , U.K
| |
Collapse
|
18
|
|
19
|
Kovács Á, Dudola D, Nyitray L, Tóth G, Nagy Z, Gáspári Z. Detection of single alpha-helices in large protein sequence sets using hardware acceleration. J Struct Biol 2018; 204:109-116. [PMID: 29908248 DOI: 10.1016/j.jsb.2018.06.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2017] [Revised: 06/11/2018] [Accepted: 06/12/2018] [Indexed: 12/13/2022]
Abstract
Single alpha-helices (SAHs) are increasingly recognized as important structural and functional elements of proteins. Comprehensive identification of SAH segments in large protein datasets was largely hindered by the slow speed of the most restrictive prediction tool for their identification, FT_CHARGE on common hardware. We have previously implemented an FPGA-based version of this tool allowing fast analysis of a large number of sequences. Using this implementation, we have set up of a semi-automated pipeline capable of analyzing full UniProt releases in reasonable time and compiling monthly updates of a comprehensive database of SAH segments. Releases of this database, denoted CSAHDB, is available on the CSAHserver 2 website at csahserver.itk.ppke.hu. An overview of human SAH-containing sequences combined with a literature survey suggests specific roles of SAH segments in proteins involved in RNA-based regulation processes as well as cytoskeletal proteins, a number of which is also linked to the development and function of synapses.
Collapse
Affiliation(s)
- Ákos Kovács
- Faculty of Information Technology and Bionics, Pázmány Péter Catholic University, Budapest, Hungary
| | - Dániel Dudola
- Faculty of Information Technology and Bionics, Pázmány Péter Catholic University, Budapest, Hungary
| | - László Nyitray
- Department of Biochemistry, Eötvös Loránd University, Budapest, Hungary
| | - Gábor Tóth
- Department for Research and Development, National Research, Development and Innovation Office, Budapest, Hungary
| | - Zoltán Nagy
- Faculty of Information Technology and Bionics, Pázmány Péter Catholic University, Budapest, Hungary.
| | - Zoltán Gáspári
- Faculty of Information Technology and Bionics, Pázmány Péter Catholic University, Budapest, Hungary.
| |
Collapse
|
20
|
Simm D, Kollmar M. Waggawagga-CLI: A command-line tool for predicting stable single α-helices (SAH-domains), and the SAH-domain distribution across eukaryotes. PLoS One 2018; 13:e0191924. [PMID: 29444145 PMCID: PMC5812594 DOI: 10.1371/journal.pone.0191924] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Accepted: 01/12/2018] [Indexed: 12/15/2022] Open
Abstract
Stable single-alpha helices (SAH-domains) function as rigid connectors and constant force springs between structural domains, and can provide contact surfaces for protein-protein and protein-RNA interactions. SAH-domains mainly consist of charged amino acids and are monomeric and stable in polar solutions, characteristics which distinguish them from coiled-coil domains and intrinsically disordered regions. Although the number of reported SAH-domains is steadily increasing, genome-wide analyses of SAH-domains in eukaryotic genomes are still missing. Here, we present Waggawagga-CLI, a command-line tool for predicting and analysing SAH-domains in protein sequence datasets. Using Waggawagga-CLI we predicted SAH-domains in 24 datasets from eukaryotes across the tree of life. SAH-domains were predicted in 0.5 to 3.5% of the protein-coding content per species. SAH-domains are particularly present in longer proteins supporting their function as structural building block in multi-domain proteins. In human, SAH-domains are mainly used as alternative building blocks not being present in all transcripts of a gene. Gene ontology analysis showed that yeast proteins with SAH-domains are particular enriched in macromolecular complex subunit organization, cellular component biogenesis and RNA metabolic processes, and that they have a strong nuclear and ribonucleoprotein complex localization and function in ribosome and nucleic acid binding. Human proteins with SAH-domains have roles in all types of RNA processing and cytoskeleton organization, and are predicted to function in RNA binding, protein binding involved in cell and cell-cell adhesion, and cytoskeletal protein binding. Waggawagga-CLI allows the user to adjust the stabilizing and destabilizing contribution of amino acid interactions in i,i+3 and i,i+4 spacings, and provides extensive flexibility for user-designed analyses.
Collapse
Affiliation(s)
- Dominic Simm
- Group Systems Biology of Motor Proteins, Department of NMR-based Structural Biology, Max-Planck-Institute for Biophysical Chemistry, Göttingen, Germany
- Theoretical Computer Science and Algorithmic Methods, Institute of Computer Science, Georg-August-University Göttingen, Göttingen, Germany
| | - Martin Kollmar
- Group Systems Biology of Motor Proteins, Department of NMR-based Structural Biology, Max-Planck-Institute for Biophysical Chemistry, Göttingen, Germany
- * E-mail:
| |
Collapse
|
21
|
Batchelor M, Wolny M, Kurzawa M, Dougan L, Knight PJ, Peckham M. Determining Stable Single Alpha Helical (SAH) Domain Properties by Circular Dichroism and Atomic Force Microscopy. Methods Mol Biol 2018; 1805:185-211. [PMID: 29971719 DOI: 10.1007/978-1-4939-8556-2_10] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Stable, single α-helical (SAH) domains exist in a number of unconventional myosin isoforms, as well as other proteins. These domains are formed from sequences rich in charged residues (Arg, Lys, and Glu), they can be hundreds of residues long, and in isolation they can tolerate significant changes in pH and salt concentration without loss in helicity. Here we describe methods for the preparation and purification of SAH domains and SAH domain-containing constructs, using the myosin 10 SAH domain as an example. We go on to describe the use of circular dichroism spectroscopy and force spectroscopy with the atomic force microscope for the elucidation of structural and mechanical properties of these unusual helical species.
Collapse
Affiliation(s)
- Matthew Batchelor
- Astbury Centre for Structural Molecular Biology and School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK
| | - Marcin Wolny
- Astbury Centre for Structural Molecular Biology and School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK
| | - Marta Kurzawa
- Astbury Centre for Structural Molecular Biology and School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK
| | - Lorna Dougan
- Astbury Centre for Structural Molecular Biology and School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, UK
| | - Peter J Knight
- Astbury Centre for Structural Molecular Biology and School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK
| | - Michelle Peckham
- Astbury Centre for Structural Molecular Biology and School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK.
| |
Collapse
|
22
|
Heimsath EG, Yim YI, Mustapha M, Hammer JA, Cheney RE. Myosin-X knockout is semi-lethal and demonstrates that myosin-X functions in neural tube closure, pigmentation, hyaloid vasculature regression, and filopodia formation. Sci Rep 2017; 7:17354. [PMID: 29229982 PMCID: PMC5725431 DOI: 10.1038/s41598-017-17638-x] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2017] [Accepted: 11/28/2017] [Indexed: 01/07/2023] Open
Abstract
Myosin-X (Myo10) is an unconventional myosin best known for its striking localization to the tips of filopodia. Despite the broad expression of Myo10 in vertebrate tissues, its functions at the organismal level remain largely unknown. We report here the generation of KO-first (Myo10tm1a/tm1a), floxed (Myo10tm1c/tm1c), and KO mice (Myo10tm1d/tm1d). Complete knockout of Myo10 is semi-lethal, with over half of homozygous KO embryos exhibiting exencephaly, a severe defect in neural tube closure. All Myo10 KO mice that survive birth exhibit a white belly spot, all have persistent fetal vasculature in the eye, and ~50% have webbed digits. Myo10 KO mice that survive birth can breed and produce litters of KO embryos, demonstrating that Myo10 is not absolutely essential for mitosis, meiosis, adult survival, or fertility. KO-first mice and an independent spontaneous deletion (Myo10m1J/m1J) exhibit the same core phenotypes. During retinal angiogenesis, KO mice exhibit a ~50% decrease in endothelial filopodia, demonstrating that Myo10 is required to form normal numbers of filopodia in vivo. The Myo10 mice generated here demonstrate that Myo10 has important functions in mammalian development and provide key tools for defining the functions of Myo10 in vivo.
Collapse
Affiliation(s)
- Ernest G Heimsath
- Department of Cell Biology and Physiology and Lineberger Comprehensive Cancer Center, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Yang-In Yim
- Cell Biology and Physiology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Mirna Mustapha
- Department of Otolaryngology, Stanford University School of Medicine, Palo Alto, CA, 94305, USA
| | - John A Hammer
- Cell Biology and Physiology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Richard E Cheney
- Department of Cell Biology and Physiology and Lineberger Comprehensive Cancer Center, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA. .,Cell Biology and Physiology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, 20892, USA.
| |
Collapse
|
23
|
Budamagunta MS, Guo F, Sun N, Shibata B, FitzGerald PG, Voss JC, Hess JF. Production of recombinant human tektin 1, 2, and 4 and in vitro assembly of human tektin 1. Cytoskeleton (Hoboken) 2017; 75:3-11. [PMID: 29108134 DOI: 10.1002/cm.21418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 10/24/2017] [Accepted: 11/01/2017] [Indexed: 11/10/2022]
Abstract
Proteins predicted to be composed of large stretches of coiled-coil structure have often proven difficult to crystallize for structural determination. We have successfully applied EPR spectroscopic techniques to the study of the structure and assembly of full-length human vimentin assembled into native 11 nm filaments, in physiologic solution, circumventing the limitations of crystallizing shorter peptide sequences. Tektins are a small family of highly alpha helical filamentous proteins found in the doublet microtubules of cilia and related structures. Tektins exhibit several similarities to intermediate filaments (IFs): moderate molecular weight, highly alpha helical, hypothesized to be coiled-coil, and homo- and heteromeric assembly into long smooth filaments. In this report, we show the application of IF research methodologies to the study of tektin structure and assembly. To begin in vitro studies, expression constructs for human tektins 1, 2, and 4 were synthesized. Recombinant tektins were produced in E. coli and purified by chromatography. Preparations of tektin 1 successfully formed filaments. The recombinant human tektin 1 was used to produce antibodies which recognized an antigen in mouse testes, most likely present in sperm flagella. Finally, we report the creation of seven mutants to analyze predictions of coiled-coil structure in the rod 1A domain of tektin 1. Although this region is predicted to be coiled-coil, our EPR analysis does not reflect the parallel, in register, coiled-coil structure as demonstrated in vimentin and kinesin. These results document that tektin can be successfully expressed and assembled in vitro, and that SDSL EPR techniques can be used for structural analysis.
Collapse
Affiliation(s)
- M S Budamagunta
- Department of Biochemistry and Molecular Medicine, School of Medicine, University of California, Davis, California, 95616
| | - F Guo
- Department of Molecular and Cellular Biology, University of California, Davis, California, 95616
| | - N Sun
- Department of Cell Biology and Human Anatomy, School of Medicine, University of California, Davis, California, 95616
| | - B Shibata
- Department of Cell Biology and Human Anatomy, School of Medicine, University of California, Davis, California, 95616
| | - P G FitzGerald
- Department of Cell Biology and Human Anatomy, School of Medicine, University of California, Davis, California, 95616
| | - J C Voss
- Department of Biochemistry and Molecular Medicine, School of Medicine, University of California, Davis, California, 95616
| | - J F Hess
- Department of Cell Biology and Human Anatomy, School of Medicine, University of California, Davis, California, 95616
| |
Collapse
|
24
|
Fili N, Hari-Gupta Y, Dos Santos Á, Cook A, Poland S, Ameer-Beg SM, Parsons M, Toseland CP. NDP52 activates nuclear myosin VI to enhance RNA polymerase II transcription. Nat Commun 2017; 8:1871. [PMID: 29187741 PMCID: PMC5707354 DOI: 10.1038/s41467-017-02050-w] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 10/30/2017] [Indexed: 11/09/2022] Open
Abstract
Myosin VI (MVI) has been found to be overexpressed in ovarian, breast and prostate cancers. Moreover, it has been shown to play a role in regulating cell proliferation and migration, and to interact with RNA Polymerase II (RNAPII). Here, we find that backfolding of MVI regulates its ability to bind DNA and that a putative transcription co-activator NDP52 relieves the auto-inhibition of MVI to enable DNA binding. Additionally, we show that the MVI-NDP52 complex binds RNAPII, which is critical for transcription, and that depletion of NDP52 or MVI reduces steady-state mRNA levels. Lastly, we demonstrate that MVI directly interacts with nuclear receptors to drive expression of target genes, thereby suggesting a link to cell proliferation and migration. Overall, we suggest MVI may function as an auxiliary motor to drive transcription.
Collapse
Affiliation(s)
- Natalia Fili
- School of Biosciences, University of Kent, Canterbury, CT2 7NJ, UK
| | - Yukti Hari-Gupta
- School of Biosciences, University of Kent, Canterbury, CT2 7NJ, UK
| | - Ália Dos Santos
- School of Biosciences, University of Kent, Canterbury, CT2 7NJ, UK
| | - Alexander Cook
- School of Biosciences, University of Kent, Canterbury, CT2 7NJ, UK
| | - Simon Poland
- Randall Division of Cell and Molecular Biophysics, King's College London, Guys Campus, London, SE1 1UL, UK
| | - Simon M Ameer-Beg
- Randall Division of Cell and Molecular Biophysics, King's College London, Guys Campus, London, SE1 1UL, UK
| | - Maddy Parsons
- Randall Division of Cell and Molecular Biophysics, King's College London, Guys Campus, London, SE1 1UL, UK
| | | |
Collapse
|
25
|
Vavra KC, Xia Y, Rock RS. Competition between Coiled-Coil Structures and the Impact on Myosin-10 Bundle Selection. Biophys J 2017; 110:2517-2527. [PMID: 27276269 DOI: 10.1016/j.bpj.2016.04.048] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Revised: 04/28/2016] [Accepted: 04/29/2016] [Indexed: 12/27/2022] Open
Abstract
Coiled-coil fusions are a useful approach to enforce dimerization in protein engineering. However, the final structures of coiled-coil fusion proteins have received relatively little attention. Here, we determine the structural outcome of adjacent parallel and antiparallel coiled coils. The targets are coiled coils that stabilize myosin-10 in single-molecule biophysical studies. We reveal the solution structure of a short, antiparallel, myosin-10 coiled-coil fused to the parallel GCN4-p1 coiled coil. Surprisingly, this structure is a continuous, antiparallel coiled coil where GCN4-p1 pairs with myosin-10 rather than itself. We also show that longer myosin-10 segments in these parallel/antiparallel fusions are dynamic and do not fold cooperatively. Our data resolve conflicting results on myosin-10 selection of actin filament bundles, demonstrating the importance of understanding coiled-coil orientation and stability.
Collapse
Affiliation(s)
- Kevin C Vavra
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, Illinois
| | - Youlin Xia
- Minnesota NMR Center, University of Minnesota, Minneapolis, Minnesota
| | - Ronald S Rock
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, Illinois.
| |
Collapse
|
26
|
Sato O, Komatsu S, Sakai T, Tsukasaki Y, Tanaka R, Mizutani T, Watanabe TM, Ikebe R, Ikebe M. Human myosin VIIa is a very slow processive motor protein on various cellular actin structures. J Biol Chem 2017; 292:10950-10960. [PMID: 28507101 DOI: 10.1074/jbc.m116.765966] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Revised: 05/11/2017] [Indexed: 11/06/2022] Open
Abstract
Human myosin VIIa (MYO7A) is an actin-linked motor protein associated with human Usher syndrome (USH) type 1B, which causes human congenital hearing and visual loss. Although it has been thought that the role of human myosin VIIa is critical for USH1 protein tethering with actin and transportation along actin bundles in inner-ear hair cells, myosin VIIa's motor function remains unclear. Here, we studied the motor function of the tail-truncated human myosin VIIa dimer (HM7AΔTail/LZ) at the single-molecule level. We found that the HM7AΔTail/LZ moves processively on single actin filaments with a step size of 35 nm. Dwell-time distribution analysis indicated an average waiting time of 3.4 s, yielding ∼0.3 s-1 for the mechanical turnover rate; hence, the velocity of HM7AΔTail/LZ was extremely slow, at 11 nm·s-1 We also examined HM7AΔTail/LZ movement on various actin structures in demembranated cells. HM7AΔTail/LZ showed unidirectional movement on actin structures at cell edges, such as lamellipodia and filopodia. However, HM7AΔTail/LZ frequently missed steps on actin tracks and exhibited bidirectional movement at stress fibers, which was not observed with tail-truncated myosin Va. These results suggest that the movement of the human myosin VIIa motor protein is more efficient on lamellipodial and filopodial actin tracks than on stress fibers, which are composed of actin filaments with different polarity, and that the actin structures influence the characteristics of cargo transportation by human myosin VIIa. In conclusion, myosin VIIa movement appears to be suitable for translocating USH1 proteins on stereocilia actin bundles in inner-ear hair cells.
Collapse
Affiliation(s)
- Osamu Sato
- From the Department of Cellular and Molecular Biology, University of Texas Health Science Center at Tyler, Tyler, Texas 75708
| | - Satoshi Komatsu
- From the Department of Cellular and Molecular Biology, University of Texas Health Science Center at Tyler, Tyler, Texas 75708
| | - Tsuyoshi Sakai
- From the Department of Cellular and Molecular Biology, University of Texas Health Science Center at Tyler, Tyler, Texas 75708
| | - Yoshikazu Tsukasaki
- From the Department of Cellular and Molecular Biology, University of Texas Health Science Center at Tyler, Tyler, Texas 75708.,Department of Pharmacology, University of Illinois College of Medicine, Chicago, Illinois 60612
| | - Ryosuke Tanaka
- Graduate School of Information Science and Technology, Hokkaido University, Sapporo 060-0814, Japan
| | - Takeomi Mizutani
- Department of Advanced Transdisciplinary Sciences, Faculty of Advanced Life Science, Hokkaido University, Sapporo 060-0810, Japan, and
| | - Tomonobu M Watanabe
- Laboratory for Comprehensive Bioimaging, RIKEN Quantitative Biology Center, Suita, Osaka 565-0874, Japan
| | - Reiko Ikebe
- From the Department of Cellular and Molecular Biology, University of Texas Health Science Center at Tyler, Tyler, Texas 75708
| | - Mitsuo Ikebe
- From the Department of Cellular and Molecular Biology, University of Texas Health Science Center at Tyler, Tyler, Texas 75708,
| |
Collapse
|
27
|
Simm D, Hatje K, Kollmar M. Distribution and evolution of stable single α-helices (SAH domains) in myosin motor proteins. PLoS One 2017; 12:e0174639. [PMID: 28369123 PMCID: PMC5378345 DOI: 10.1371/journal.pone.0174639] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Accepted: 03/13/2017] [Indexed: 11/19/2022] Open
Abstract
Stable single-alpha helices (SAHs) are versatile structural elements in many prokaryotic and eukaryotic proteins acting as semi-flexible linkers and constant force springs. This way SAH-domains function as part of the lever of many different myosins. Canonical myosin levers consist of one or several IQ-motifs to which light chains such as calmodulin bind. SAH-domains provide flexibility in length and stiffness to the myosin levers, and may be particularly suited for myosins working in crowded cellular environments. Although the function of the SAH-domains in human class-6 and class-10 myosins has well been characterised, the distribution of the SAH-domain in all myosin subfamilies and across the eukaryotic tree of life remained elusive. Here, we analysed the largest available myosin sequence dataset consisting of 7919 manually annotated myosin sequences from 938 species representing all major eukaryotic branches using the SAH-prediction algorithm of Waggawagga, a recently developed tool for the identification of SAH-domains. With this approach we identified SAH-domains in more than one third of the supposed 79 myosin subfamilies. Depending on the myosin class, the presence of SAH-domains can range from a few to almost all class members indicating complex patterns of independent and taxon-specific SAH-domain gain and loss.
Collapse
Affiliation(s)
- Dominic Simm
- Group Systems Biology of Motor Proteins, Department of NMR-based Structural Biology, Max-Planck-Institute for Biophysical Chemistry, Göttingen, Germany
- Theoretical Computer Science and Algorithmic Methods, Institute of Computer Science, Georg-August-University Göttingen, Göttingen, Germany
| | - Klas Hatje
- Group Systems Biology of Motor Proteins, Department of NMR-based Structural Biology, Max-Planck-Institute for Biophysical Chemistry, Göttingen, Germany
| | - Martin Kollmar
- Group Systems Biology of Motor Proteins, Department of NMR-based Structural Biology, Max-Planck-Institute for Biophysical Chemistry, Göttingen, Germany
- * E-mail:
| |
Collapse
|
28
|
Activated full-length myosin-X moves processively on filopodia with large steps toward diverse two-dimensional directions. Sci Rep 2017; 7:44237. [PMID: 28287133 PMCID: PMC5346999 DOI: 10.1038/srep44237] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Accepted: 02/06/2017] [Indexed: 12/25/2022] Open
Abstract
Myosin-X, (Myo 10), is an unconventional myosin that transports the specific cargos to filopodial tips, and is associated with the mechanism underlying filopodia formation and extension. To clarify the innate motor characteristic, we studied the single molecule movement of a full-length myosin-X construct with leucine zipper at the C-terminal end of the tail (M10FullLZ) and the tail-truncated myosin-X without artificial dimerization motif (BAP-M101–979HMM). M10FullLZ localizes at the tip of filopodia like myosin-X full-length (M10Full). M10FullLZ moves on actin filaments in the presence of PI(3,4,5)P3, an activator of myosin-X. Single molecule motility analysis revealed that the step sizes of both M10FullLZ and BAP-M101–979HMM are widely distributed on single actin filaments that is consistent with electron microscopy observation. M10FullLZ moves on filopodial actin bundles of cells with a mean step size (~36 nm), similar to the step size on single actin filaments (~38 nm). Cartesian plot analysis revealed that M10FullLZ meandered on filopodial actin bundles to both x- and y- directions. These results suggest that the lever-arm of full-length myosin-X is flexible enough to processively steps on different actin filaments within the actin bundles of filopodia. This characteristic of myosin-X may facilitate actin filament convergence for filopodia production.
Collapse
|
29
|
Wolny M, Batchelor M, Bartlett GJ, Baker EG, Kurzawa M, Knight PJ, Dougan L, Woolfson DN, Paci E, Peckham M. Characterization of long and stable de novo single alpha-helix domains provides novel insight into their stability. Sci Rep 2017; 7:44341. [PMID: 28287151 PMCID: PMC5347031 DOI: 10.1038/srep44341] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Accepted: 02/07/2017] [Indexed: 12/22/2022] Open
Abstract
Naturally-occurring single α-helices (SAHs), are rich in Arg (R), Glu (E) and Lys (K) residues, and stabilized by multiple salt bridges. Understanding how salt bridges promote their stability is challenging as SAHs are long and their sequences highly variable. Thus, we designed and tested simple de novo 98-residue polypeptides containing 7-residue repeats (AEEEXXX, where X is K or R) expected to promote salt-bridge formation between Glu and Lys/Arg. Lys-rich sequences (EK3 (AEEEKKK) and EK2R1 (AEEEKRK)) both form SAHs, of which EK2R1 is more helical and thermo-stable suggesting Arg increases stability. Substituting Lys with Arg (or vice versa) in the naturally-occurring myosin-6 SAH similarly increased (or decreased) its stability. However, Arg-rich de novo sequences (ER3 (AEEERRR) and EK1R2 (AEEEKRR)) aggregated. Combining a PDB analysis with molecular modelling provides a rational explanation, demonstrating that Glu and Arg form salt bridges more commonly, utilize a wider range of rotamer conformations, and are more dynamic than Glu-Lys. This promiscuous nature of Arg helps explain the increased propensity of de novo Arg-rich SAHs to aggregate. Importantly, the specific K:R ratio is likely to be important in determining helical stability in de novo and naturally-occurring polypeptides, giving new insight into how single α-helices are stabilized.
Collapse
Affiliation(s)
- Marcin Wolny
- Astbury Centre for Structural Molecular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK
| | - Matthew Batchelor
- Astbury Centre for Structural Molecular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK
| | - Gail J. Bartlett
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS, UK
| | - Emily G. Baker
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS, UK
| | - Marta Kurzawa
- Astbury Centre for Structural Molecular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK
| | - Peter J. Knight
- Astbury Centre for Structural Molecular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK
| | - Lorna Dougan
- Astbury Centre for Structural Molecular Biology and School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, UK
| | - Derek N. Woolfson
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS, UK
- School of Biochemistry, University of Bristol, Biomedical Sciences Building, Bristol, BS8 1TD, UK
- BrisSynBio, University of Bristol, Life Sciences Building, Bristol, BS8 1TQ, UK
| | - Emanuele Paci
- Astbury Centre for Structural Molecular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK
| | - Michelle Peckham
- Astbury Centre for Structural Molecular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK
| |
Collapse
|
30
|
Li J, Chen Y, Deng Y, Unarta IC, Lu Q, Huang X, Zhang M. Ca 2+-Induced Rigidity Change of the Myosin VIIa IQ Motif-Single α Helix Lever Arm Extension. Structure 2017; 25:579-591.e4. [PMID: 28262393 DOI: 10.1016/j.str.2017.02.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Revised: 12/08/2016] [Accepted: 02/09/2017] [Indexed: 11/17/2022]
Abstract
Several unconventional myosins contain a highly charged single α helix (SAH) immediately following the calmodulin (CaM) binding IQ motifs, functioning to extend lever arms of these myosins. How such SAH is connected to the IQ motifs and whether the conformation of the IQ motifs-SAH segments are regulated by Ca2+ fluctuations are not known. Here, we demonstrate by solving its crystal structure that the predicted SAH of myosin VIIa (Myo7a) forms a stable SAH. The structure of Myo7a IQ5-SAH segment in complex with apo-CaM reveals that the SAH sequence can extend the length of the Myo7a lever arm. Although Ca2+-CaM remains bound to IQ5-SAH, the Ca2+-induced CaM binding mode change softens the conformation of the IQ5-SAH junction, revealing a Ca2+-induced lever arm flexibility change for Myo7a. We further demonstrate that the last IQ motif of several other myosins also binds to both apo- and Ca2+-CaM, suggesting a common Ca2+-induced conformational regulation mechanism.
Collapse
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.
| | - Yiyun Chen
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Yisong Deng
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Ilona Christy Unarta
- Department of Chemistry, 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; Center of Systems Biology and Human Health, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China; Institute for Advanced Study, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Xuhui Huang
- Department of Chemistry, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China; Center of Systems Biology and Human Health, 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, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China; Institute for Advanced Study, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China.
| |
Collapse
|
31
|
Dudola D, Tóth G, Nyitray L, Gáspári Z. Consensus Prediction of Charged Single Alpha-Helices with CSAHserver. Methods Mol Biol 2017; 1484:25-34. [PMID: 27787817 DOI: 10.1007/978-1-4939-6406-2_3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Charged single alpha-helices (CSAHs) constitute a rare structural motif. CSAH is characterized by a high density of regularly alternating residues with positively and negatively charged side chains. Such segments exhibit unique structural properties; however, there are only a handful of proteins where its existence is experimentally verified. Therefore, establishing a pipeline that is capable of predicting the presence of CSAH segments with a low false positive rate is of considerable importance. Here we describe a consensus-based approach that relies on two conceptually different CSAH detection methods and a final filter based on the estimated helix-forming capabilities of the segments. This pipeline was shown to be capable of identifying previously uncharacterized CSAH segments that could be verified experimentally. The method is available as a web server at http://csahserver.itk.ppke.hu and also a downloadable standalone program suitable to scan larger sequence collections.
Collapse
Affiliation(s)
- Dániel Dudola
- Faculty of Information Technology and Bionics, Pázmány Péter Catholic University, Práter u. 50/A, Budapest, 1083, Hungary
| | - Gábor Tóth
- Department of Medical and Biological Sciences, National Research, Development and Innovation Office, Budapest, Hungary
| | - László Nyitray
- Department of Biochemistry, Eötvös Loránd University, Budapest, Hungary
| | - Zoltán Gáspári
- Faculty of Information Technology and Bionics, Pázmány Péter Catholic University, Práter u. 50/A, Budapest, 1083, Hungary.
| |
Collapse
|
32
|
MyTH4-FERM myosins have an ancient and conserved role in filopod formation. Proc Natl Acad Sci U S A 2016; 113:E8059-E8068. [PMID: 27911821 DOI: 10.1073/pnas.1615392113] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The formation of filopodia in Metazoa and Amoebozoa requires the activity of myosin 10 (Myo10) in mammalian cells and of Dictyostelium unconventional myosin 7 (DdMyo7) in the social amoeba Dictyostelium However, the exact roles of these MyTH4-FERM myosins (myosin tail homology 4-band 4.1, ezrin, radixin, moesin; MF) in the initiation and elongation of filopodia are not well defined and may reflect conserved functions among phylogenetically diverse MF myosins. Phylogenetic analysis of MF myosin domains suggests that a single ancestral MF myosin existed with a structure similar to DdMyo7, which has two MF domains, and that subsequent duplications in the metazoan lineage produced its functional homolog Myo10. The essential functional features of the DdMyo7 myosin were identified using quantitative live-cell imaging to characterize the ability of various mutants to rescue filopod formation in myo7-null cells. The two MF domains were found to function redundantly in filopod formation with the C-terminal FERM domain regulating both the number of filopodia and their elongation velocity. DdMyo7 mutants consisting solely of the motor plus a single MyTH4 domain were found to be capable of rescuing the formation of filopodia, establishing the minimal elements necessary for the function of this myosin. Interestingly, a chimeric myosin with the Myo10 MF domain fused to the DdMyo7 motor also was capable of rescuing filopod formation in the myo7-null mutant, supporting fundamental functional conservation between these two distant myosins. Together, these findings reveal that MF myosins have an ancient and conserved role in filopod formation.
Collapse
|
33
|
Ulrich AKC, Seeger M, Schütze T, Bartlick N, Wahl MC. Scaffolding in the Spliceosome via Single α Helices. Structure 2016; 24:1972-1983. [PMID: 27773687 DOI: 10.1016/j.str.2016.09.007] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Revised: 09/08/2016] [Accepted: 09/28/2016] [Indexed: 12/16/2022]
Abstract
The spliceosomal B complex-specific protein Prp38 forms a complex with the intrinsically unstructured proteins MFAP1 and Snu23. Our binding and crystal structure analyses show that MFAP1 and Snu23 contact Prp38 via ER/K motif-stabilized single α helices, which have previously been recognized only as rigid connectors or force springs between protein domains. A variant of the Prp38-binding single α helix of MFAP1, in which ER/K motifs not involved in Prp38 binding were mutated, was less α-helical in isolation and showed a reduced Prp38 affinity, with opposing tendencies in interaction enthalpy and entropy. Our results indicate that the strengths of single α helix-based interactions can be tuned by the degree of helix stabilization in the unbound state. MFAP1, Snu23, and several other spliceosomal proteins contain multiple regions that likely form single α helices via which they might tether several binding partners and act as intermittent scaffolds that facilitate remodeling steps during assembly of an active spliceosome.
Collapse
Affiliation(s)
- Alexander K C Ulrich
- Laboratory of Structural Biochemistry, Freie Universität Berlin, Takustraße 6, 14195 Berlin, Germany
| | - Martin Seeger
- Laboratory of Structural Biochemistry, Freie Universität Berlin, Takustraße 6, 14195 Berlin, Germany
| | - Tonio Schütze
- Laboratory of Structural Biochemistry, Freie Universität Berlin, Takustraße 6, 14195 Berlin, Germany
| | - Natascha Bartlick
- Laboratory of Structural Biochemistry, Freie Universität Berlin, Takustraße 6, 14195 Berlin, Germany
| | - Markus C Wahl
- Laboratory of Structural Biochemistry, Freie Universität Berlin, Takustraße 6, 14195 Berlin, Germany; Helmholtz-Zentrum Berlin für Materialien und Energie, Macromolecular Crystallography, Albert-Einstein-Straße 15, 12489 Berlin, Germany.
| |
Collapse
|
34
|
The myosin X motor is optimized for movement on actin bundles. Nat Commun 2016; 7:12456. [PMID: 27580874 PMCID: PMC5025751 DOI: 10.1038/ncomms12456] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2016] [Accepted: 07/05/2016] [Indexed: 11/09/2022] Open
Abstract
Myosin X has features not found in other myosins. Its structure must underlie its unique ability to generate filopodia, which are essential for neuritogenesis, wound healing, cancer metastasis and some pathogenic infections. By determining high-resolution structures of key components of this motor, and characterizing the in vitro behaviour of the native dimer, we identify the features that explain the myosin X dimer behaviour. Single-molecule studies demonstrate that a native myosin X dimer moves on actin bundles with higher velocities and takes larger steps than on single actin filaments. The largest steps on actin bundles are larger than previously reported for artificially dimerized myosin X constructs or any other myosin. Our model and kinetic data explain why these large steps and high velocities can only occur on bundled filaments. Thus, myosin X functions as an antiparallel dimer in cells with a unique geometry optimized for movement on actin bundles.
Collapse
|
35
|
Baboolal TG, Mashanov GI, Nenasheva TA, Peckham M, Molloy JE. A Combination of Diffusion and Active Translocation Localizes Myosin 10 to the Filopodial Tip. J Biol Chem 2016; 291:22373-22385. [PMID: 27566544 PMCID: PMC5077179 DOI: 10.1074/jbc.m116.730689] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Revised: 08/24/2016] [Indexed: 11/06/2022] Open
Abstract
Myosin 10 is an actin-based molecular motor that localizes to the tips of filopodia in mammalian cells. To understand how it is targeted to this distinct region of the cell, we have used total internal reflection fluorescence microscopy to study the movement of individual full-length and truncated GFP-tagged molecules. Truncation mutants lacking the motor region failed to localize to filopodial tips but still bound transiently at the plasma membrane. Deletion of the single α-helical and anti-parallel coiled-coil forming regions, which lie between the motor and pleckstrin homology domains, reduced the instantaneous velocity of intrafilopodial movement but did not affect the number of substrate adherent filopodia. Deletion of the anti-parallel coiled-coil forming region, but not the EKR-rich region of the single α-helical domain, restored intrafilopodial trafficking, suggesting this region is important in determining myosin 10 motility. We propose a model by which myosin 10 rapidly targets to the filopodial tip via a sequential reduction in dimensionality. Molecules first undergo rapid diffusion within the three-dimensional volume of the cell body. They then exhibit periods of slower two-dimensional diffusion in the plane of the plasma membrane. Finally, they move in a unidimensional, highly directed manner along the polarized actin filament bundle within the filopodium becoming confined to a single point at the tip. Here we have observed directly each phase of the trafficking process using single molecule fluorescence imaging of live cells and have quantified our observations using single particle tracking, autocorrelation analysis, and kymographs.
Collapse
Affiliation(s)
- Thomas G Baboolal
- From the Astbury Centre for Structural Molecular Biology and Institute of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT and
| | - Gregory I Mashanov
- The Francis Crick Institute, Mill Hill Laboratory, London NW7 1AA, United Kingdom
| | - Tatiana A Nenasheva
- The Francis Crick Institute, Mill Hill Laboratory, London NW7 1AA, United Kingdom
| | - Michelle Peckham
- From the Astbury Centre for Structural Molecular Biology and Institute of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT and
| | - Justin E Molloy
- The Francis Crick Institute, Mill Hill Laboratory, London NW7 1AA, United Kingdom
| |
Collapse
|
36
|
Doležal M, Hadravová R, Kožíšek M, Bednárová L, Langerová H, Ruml T, Rumlová M. Functional and Structural Characterization of Novel Type of Linker Connecting Capsid and Nucleocapsid Protein Domains in Murine Leukemia Virus. J Biol Chem 2016; 291:20630-42. [PMID: 27514744 DOI: 10.1074/jbc.m116.746461] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Indexed: 12/24/2022] Open
Abstract
The assembly of immature retroviral particles is initiated in the cytoplasm by the binding of the structural polyprotein precursor Gag with viral genomic RNA. The protein interactions necessary for assembly are mediated predominantly by the capsid (CA) and nucleocapsid (NC) domains, which have conserved structures. In contrast, the structural arrangement of the CA-NC connecting region differs between retroviral species. In HIV-1 and Rous sarcoma virus, this region forms a rod-like structure that separates the CA and NC domains, whereas in Mason-Pfizer monkey virus, this region is densely packed, thus holding the CA and NC domains in close proximity. Interestingly, the sequence connecting the CA and NC domains in gammaretroviruses, such as murine leukemia virus (MLV), is unique. The sequence is called a charged assembly helix (CAH) due to a high number of positively and negatively charged residues. Although both computational and deletion analyses suggested that the MLV CAH forms a helical conformation, no structural or biochemical data supporting this hypothesis have been published. Using an in vitro assembly assay, alanine scanning mutagenesis, and biophysical techniques (circular dichroism, NMR, microcalorimetry, and electrophoretic mobility shift assay), we have characterized the structure and function of the MLV CAH. We provide experimental evidence that the MLV CAH belongs to a group of charged, E(R/K)-rich, single α-helices. This is the first single α-helix motif identified in viral proteins.
Collapse
Affiliation(s)
- Michal Doležal
- From the Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo náměstí 2, 16610 Prague 6
| | - Romana Hadravová
- From the Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo náměstí 2, 16610 Prague 6
| | - Milan Kožíšek
- From the Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo náměstí 2, 16610 Prague 6
| | - Lucie Bednárová
- From the Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo náměstí 2, 16610 Prague 6
| | - Hana Langerová
- the Department of Biochemistry and Microbiology, University of Chemistry and Technology, Prague 6, Technická 3, 166 28 Prague, and
| | - Tomáš Ruml
- the Department of Biochemistry and Microbiology, University of Chemistry and Technology, Prague 6, Technická 3, 166 28 Prague, and
| | - Michaela Rumlová
- From the Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo náměstí 2, 16610 Prague 6, the Department of Biotechnology, University of Chemistry and Technology, Technická 5, 166 28 Prague, Czech Republic
| |
Collapse
|
37
|
Batters C, Veigel C. Mechanics and Activation of Unconventional Myosins. Traffic 2016; 17:860-71. [PMID: 27061900 DOI: 10.1111/tra.12400] [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: 01/14/2016] [Revised: 03/07/2016] [Accepted: 03/07/2016] [Indexed: 12/01/2022]
Abstract
Many types of cellular motility are based on the myosin family of motor proteins ranging from muscle contraction to exo- and endocytosis, cytokinesis, cell locomotion or signal transduction in hearing. At the center of this wide range of motile processes lies the adaptation of the myosins for each specific mechanical task and the ability to coordinate the timing of motor protein mobilization and targeting. In recent years, great progress has been made in developing single molecule technology to characterize the diverse mechanical properties of the unconventional myosins. Here, we discuss the basic mechanisms and mechanical adaptations of unconventional myosins, and emerging principles regulating motor mobilization and targeting.
Collapse
Affiliation(s)
- Christopher Batters
- Department of Cellular Physiology, Ludwig-Maximilians-Universität München, Schillerstrasse 44, 80336, Munich, Germany.,Center for Nanosciences (CeNS) München, 80799, Munich, Germany
| | - Claudia Veigel
- Department of Cellular Physiology, Ludwig-Maximilians-Universität München, Schillerstrasse 44, 80336, Munich, Germany.,Center for Nanosciences (CeNS) München, 80799, Munich, Germany
| |
Collapse
|
38
|
Heissler SM, Sellers JR. Kinetic Adaptations of Myosins for Their Diverse Cellular Functions. Traffic 2016; 17:839-59. [PMID: 26929436 DOI: 10.1111/tra.12388] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Revised: 02/25/2016] [Accepted: 02/25/2016] [Indexed: 12/18/2022]
Abstract
Members of the myosin superfamily are involved in all aspects of eukaryotic life. Their function ranges from the transport of organelles and cargos to the generation of membrane tension, and the contraction of muscle. The diversity of physiological functions is remarkable, given that all enzymatically active myosins follow a conserved mechanoenzymatic cycle in which the hydrolysis of ATP to ADP and inorganic phosphate is coupled to either actin-based transport or tethering of actin to defined cellular compartments. Kinetic capacities and limitations of a myosin are determined by the extent to which actin can accelerate the hydrolysis of ATP and the release of the hydrolysis products and are indispensably linked to its physiological tasks. This review focuses on kinetic competencies that - together with structural adaptations - result in myosins with unique mechanoenzymatic properties targeted to their diverse cellular functions.
Collapse
Affiliation(s)
- Sarah M Heissler
- Laboratory of Molecular Physiology, National Heart, Lung, and Blood Institute, National Institutes of Health, 50 South Drive, B50/3523, 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, B50/3523, Bethesda, MD 20892-8015, USA
| |
Collapse
|
39
|
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.
Collapse
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
| |
Collapse
|
40
|
Dobson L, Nyitray L, Gáspári Z. A conserved charged single α-helix with a putative steric role in paraspeckle formation. RNA (NEW YORK, N.Y.) 2015; 21:2023-2029. [PMID: 26428695 PMCID: PMC4647456 DOI: 10.1261/rna.053058.115] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Accepted: 08/27/2015] [Indexed: 06/05/2023]
Abstract
Paraspeckles are subnuclear particles involved in the regulation of mRNA expression. They are formed by the association of DBHS family proteins and the NEAT1 long noncoding RNA. Here, we show that a recently identified structural motif, the charged single α-helix, is largely conserved in the DBHS family. Based on the available structural data and a previously suggested multimerization scheme of DBHS proteins, we built a structural model of a (PSPC1/NONO)(n) multimer that might have relevance in paraspeckle formation. Our model contains an extended coiled-coil region that is followed by and partially overlaps with the predicted charged single α-helix. We suggest that the charged single α-helix can act as an elastic ruler governing the exact positioning of the dimeric core structures relative to each other during paraspeckle assembly along the NEAT1 noncoding RNA.
Collapse
Affiliation(s)
- László Dobson
- Pázmány Péter Catholic University, Faculty of Information Technology and Bionics, H-1083 Budapest, Hungary
| | - László Nyitray
- Eötvös Loránd University, Department of Biochemistry, H-1117 Budapest, Hungary
| | - Zoltán Gáspári
- Pázmány Péter Catholic University, Faculty of Information Technology and Bionics, H-1083 Budapest, Hungary
| |
Collapse
|
41
|
Jie J, Löhr F, Barbar E. Interactions of Yeast Dynein with Dynein Light Chain and Dynactin: GENERAL IMPLICATIONS FOR INTRINSICALLY DISORDERED DUPLEX SCAFFOLDS IN MULTIPROTEIN ASSEMBLIES. J Biol Chem 2015; 290:23863-74. [PMID: 26253171 DOI: 10.1074/jbc.m115.649715] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Indexed: 11/06/2022] Open
Abstract
Intrinsically disordered protein (IDP) duplexes composed of two IDP chains cross-linked by bivalent partner proteins form scaffolds for assembly of multiprotein complexes. The N-terminal domain of dynein intermediate chain (N-IC) is one such IDP that forms a bivalent scaffold with multiple dynein light chains including LC8, a hub protein that promotes duplex formation of diverse IDP partners. N-IC also binds a subunit of the dynein regulator, dynactin. Here we characterize interactions of a yeast ortholog of N-IC (N-Pac11) with yeast LC8 (Dyn2) or with the intermediate chain-binding subunit of yeast dynactin (Nip100). Residue level changes in Pac11 structure are monitored by NMR spectroscopy, and binding energetics are monitored by isothermal titration calorimetry (ITC). N-Pac11 is monomeric and primarily disordered except for a single α-helix (SAH) at the N terminus and a short nascent helix, LH, flanked by the two Dyn2 recognition motifs. Upon binding Dyn2, the only Pac11 residues making direct protein-protein interactions are in and immediately flanking the recognition motifs. Dyn2 binding also orders LH residues of Pac11. Upon binding Nip100, only Pac11 SAH residues make direct protein-protein interactions, but LH residues at a distant sequence position and L1 residues in an adjacent linker are also ordered. The long distance, ligand-dependent ordering of residues reveals new elements of dynamic structure within IDP linker regions.
Collapse
Affiliation(s)
- Jing Jie
- From the Department of Biochemistry and Biophysics, Oregon State University, Corvallis, Oregon 97331 and
| | - Frank Löhr
- the Institute of Biophysical Chemistry, Goethe-University, D-60438 Frankfurt, Germany
| | - Elisar Barbar
- From the Department of Biochemistry and Biophysics, Oregon State University, Corvallis, Oregon 97331 and
| |
Collapse
|
42
|
Samejima K, Platani M, Wolny M, Ogawa H, Vargiu G, Knight PJ, Peckham M, Earnshaw WC. The Inner Centromere Protein (INCENP) Coil Is a Single α-Helix (SAH) Domain That Binds Directly to Microtubules and Is Important for Chromosome Passenger Complex (CPC) Localization and Function in Mitosis. J Biol Chem 2015; 290:21460-72. [PMID: 26175154 PMCID: PMC4571873 DOI: 10.1074/jbc.m115.645317] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Indexed: 11/06/2022] Open
Abstract
The chromosome passenger complex (CPC) is a master regulator of mitosis. Inner centromere protein (INCENP) acts as a scaffold regulating CPC localization and activity. During early mitosis, the N-terminal region of INCENP forms a three-helix bundle with Survivin and Borealin, directing the CPC to the inner centromere where it plays essential roles in chromosome alignment and the spindle assembly checkpoint. The C-terminal IN box region of INCENP is responsible for binding and activating Aurora B kinase. The central region of INCENP has been proposed to comprise a coiled coil domain acting as a spacer between the N- and C-terminal domains that is involved in microtubule binding and regulation of the spindle checkpoint. Here we show that the central region (213 residues) of chicken INCENP is not a coiled coil but a ∼ 32-nm-long single α-helix (SAH) domain. The N-terminal half of this domain directly binds to microtubules in vitro. By analogy with previous studies of myosin 10, our data suggest that the INCENP SAH might stretch up to ∼ 80 nm under physiological forces. Thus, the INCENP SAH could act as a flexible "dog leash," allowing Aurora B to phosphorylate dynamic substrates localized in the outer kinetochore while at the same time being stably anchored to the heterochromatin of the inner centromere. Furthermore, by achieving this flexibility via an SAH domain, the CPC avoids a need for dimerization (required for coiled coil formation), which would greatly complicate regulation of the proximity-induced trans-phosphorylation that is critical for Aurora B activation.
Collapse
Affiliation(s)
- Kumiko Samejima
- From The Wellcome Trust Centre for Cell Biology, University of Edinburgh, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, Scotland, United Kingdom and
| | - Melpomeni Platani
- From The Wellcome Trust Centre for Cell Biology, University of Edinburgh, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, Scotland, United Kingdom and
| | - Marcin Wolny
- The Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Hiromi Ogawa
- From The Wellcome Trust Centre for Cell Biology, University of Edinburgh, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, Scotland, United Kingdom and
| | - Giulia Vargiu
- From The Wellcome Trust Centre for Cell Biology, University of Edinburgh, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, Scotland, United Kingdom and
| | - Peter J Knight
- The Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Michelle Peckham
- The Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - William C Earnshaw
- From The Wellcome Trust Centre for Cell Biology, University of Edinburgh, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, Scotland, United Kingdom and
| |
Collapse
|
43
|
Sakai T, Jung HS, Sato O, Yamada MD, You DJ, Ikebe R, Ikebe M. Structure and Regulation of the Movement of Human Myosin VIIA. J Biol Chem 2015; 290:17587-98. [PMID: 26001786 DOI: 10.1074/jbc.m114.599365] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Indexed: 11/06/2022] Open
Abstract
Human myosin VIIA (HM7A) is responsible for human Usher syndrome type 1B, which causes hearing and visual loss in humans. Here we studied the regulation of HM7A. The actin-activated ATPase activity of full-length HM7A (HM7AFull) was lower than that of tail-truncated HM7A (HM7AΔTail). Deletion of the C-terminal 40 amino acids and mutation of the basic residues in this region (R2176A or K2179A) abolished the inhibition. Electron microscopy revealed that HM7AFull is a monomer in which the tail domain bends back toward the head-neck domain to form a compact structure. This compact structure is extended at high ionic strength or in the presence of Ca(2+). Although myosin VIIA has five isoleucine-glutamine (IQ) motifs, the neck length seems to be shorter than the expected length of five bound calmodulins. Supporting this observation, the IQ domain bound only three calmodulins in Ca(2+), and the first IQ motif failed to bind calmodulin in EGTA. These results suggest that the unique IQ domain of HM7A is important for the tail-neck interaction and, therefore, regulation. Cellular studies revealed that dimer formation of HM7A is critical for its translocation to filopodial tips and that the tail domain (HM7ATail) markedly reduced the filopodial tip localization of the HM7AΔTail dimer, suggesting that the tail-inhibition mechanism is operating in vivo. The translocation of the HM7AFull dimer was significantly less than that of the HM7AΔTail dimer, and R2176A/R2179A mutation rescued the filopodial tip translocation. These results suggest that HM7A can transport its cargo molecules, such as USH1 proteins, upon release of the tail-dependent inhibition.
Collapse
Affiliation(s)
- Tsuyoshi Sakai
- From the Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, Massachusetts 01605, the Department of Cellular and Molecular Biology, University of Texas Health Science Center at Tyler, Tyler, Texas 75708
| | - Hyun Suk Jung
- the Division of Electron Microscopic Research, Korea Basic Science Institute, 169-148 Gwahak-ro, Daejeon 305-333, Korea, and the Department of Biochemistry, College of Natural Sciences, Kangwon National University, 1, Kangwondaehak-gil, Chuncheon-si, Gangwon-do 200-701, Korea
| | - Osamu Sato
- From the Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, Massachusetts 01605, the Department of Cellular and Molecular Biology, University of Texas Health Science Center at Tyler, Tyler, Texas 75708
| | - Masafumi D Yamada
- From the Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - Dong-Ju You
- the Division of Electron Microscopic Research, Korea Basic Science Institute, 169-148 Gwahak-ro, Daejeon 305-333, Korea, and
| | - Reiko Ikebe
- From the Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, Massachusetts 01605, the Department of Cellular and Molecular Biology, University of Texas Health Science Center at Tyler, Tyler, Texas 75708
| | - Mitsuo Ikebe
- From the Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, Massachusetts 01605, the Department of Cellular and Molecular Biology, University of Texas Health Science Center at Tyler, Tyler, Texas 75708,
| |
Collapse
|
44
|
Abstract
Myosin-X (Myo10) is a motor protein best known for its role in filopodia formation. New research implicates Myo10 in a number of disease states including cancer metastasis and pathogen infection. This review focuses on these developments with emphasis on the emerging roles of Myo10 in formation of cancer cell protrusions and metastasis. A number of aggressive cancers show high levels of Myo10 expression and knockdown of Myo10 has been shown to dramatically limit cancer cell motility in 2D and 3D systems. Myo10 knockdown also limits spread of intracellular pathogens marburgvirus and Shigella flexneri. Consideration is given to how these properties might arise and potential paths of future research.
Collapse
Affiliation(s)
- David S Courson
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, United States; Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, United States
| | - Richard E Cheney
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, United States; Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, United States.
| |
Collapse
|
45
|
Baker EG, Bartlett GJ, Crump MP, Sessions RB, Linden N, Faul CFJ, Woolfson DN. Local and macroscopic electrostatic interactions in single α-helices. Nat Chem Biol 2015; 11:221-8. [PMID: 25664692 PMCID: PMC4668598 DOI: 10.1038/nchembio.1739] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Accepted: 12/01/2014] [Indexed: 11/09/2022]
Abstract
The noncovalent forces that stabilize protein structures are not fully understood. One way to address this is to study equilibria between unfolded states and α-helices in peptides. Electrostatic forces-which include interactions between side chains, the backbone and side chains, and side chains and the helix macrodipole-are believed to contribute to these equilibria. Here we probe these interactions experimentally using designed peptides. We find that both terminal backbone-side chain and certain side chain-side chain interactions (which include both local effects between proximal charges and interatomic contacts) contribute much more to helix stability than side chain-helix macrodipole electrostatics, which are believed to operate at larger distances. This has implications for current descriptions of helix stability, the understanding of protein folding and the refinement of force fields for biomolecular modeling and simulations. In addition, this study sheds light on the stability of rod-like structures formed by single α-helices, which are common in natural proteins such as non-muscle myosins.
Collapse
Affiliation(s)
- Emily G. Baker
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS, UK
| | - Gail J. Bartlett
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS, UK
| | - Matthew P. Crump
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS, UK
| | - Richard B. Sessions
- School of Biochemistry, University of Bristol, Medical Sciences Building, University Walk, Bristol, BS8 1TD, UK
| | - Noah Linden
- School of Mathematics, University of Bristol, University Walk, Bristol, BS8 1TW, UK
| | - Charl F. J. Faul
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS, UK
| | - Derek N. Woolfson
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS, UK
- School of Biochemistry, University of Bristol, Medical Sciences Building, University Walk, Bristol, BS8 1TD, UK
| |
Collapse
|
46
|
Abstract
The human genome contains 39 myosin genes, divided up into 12 different classes. The structure, cellular function and biochemical properties of many of these isoforms remain poorly characterized and there is still some controversy as to whether some myosin isoforms are monomers or dimers. Myosin isoforms 6 and 10 contain a stable single α-helical (SAH) domain, situated just after the canonical lever. The SAH domain is stiff enough to be able to lengthen the lever allowing the myosin to take a larger step. In addition, atomic force microscopy and atomistic simulations show that SAH domains unfold at relatively low forces and have a high propensity to refold. These properties are likely to be important for protein function, enabling motors to carry cargo in dense actin networks, and other proteins to remain attached to binding partners in the crowded cell.
Collapse
|
47
|
Norris SR, Soppina V, Dizaji AS, Schimert KI, Sept D, Cai D, Sivaramakrishnan S, Verhey KJ. A method for multiprotein assembly in cells reveals independent action of kinesins in complex. ACTA ACUST UNITED AC 2014; 207:393-406. [PMID: 25365993 PMCID: PMC4226728 DOI: 10.1083/jcb.201407086] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
A new system for generating cellular protein assemblies of defined spacing and composition reveals that kinesin motors located near each other function independently rather than cooperatively and are influenced primarily by the characteristics of the microtubule track on which they are moving. Teams of processive molecular motors are critical for intracellular transport and organization, yet coordination between motors remains poorly understood. Here, we develop a system using protein components to generate assemblies of defined spacing and composition inside cells. This system is applicable to studying macromolecular complexes in the context of cell signaling, motility, and intracellular trafficking. We use the system to study the emergent behavior of kinesin motors in teams. We find that two kinesin motors in complex act independently (do not help or hinder each other) and can alternate their activities. For complexes containing a slow kinesin-1 and fast kinesin-3 motor, the slow motor dominates motility in vitro but the fast motor can dominate on certain subpopulations of microtubules in cells. Both motors showed dynamic interactions with the complex, suggesting that motor–cargo linkages are sensitive to forces applied by the motors. We conclude that kinesin motors in complex act independently in a manner regulated by the microtubule track.
Collapse
Affiliation(s)
- Stephen R Norris
- Department of Biophysics, Department of Cell and Developmental Biology, and Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109 Department of Biophysics, Department of Cell and Developmental Biology, and Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109
| | - Virupakshi Soppina
- Department of Biophysics, Department of Cell and Developmental Biology, and Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109
| | - Aslan S Dizaji
- Department of Biophysics, Department of Cell and Developmental Biology, and Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109
| | - Kristin I Schimert
- Department of Biophysics, Department of Cell and Developmental Biology, and Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109
| | - David Sept
- Department of Biophysics, Department of Cell and Developmental Biology, and Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109
| | - Dawen Cai
- Department of Biophysics, Department of Cell and Developmental Biology, and Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109
| | - Sivaraj Sivaramakrishnan
- Department of Biophysics, Department of Cell and Developmental Biology, and Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109 Department of Biophysics, Department of Cell and Developmental Biology, and Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109 Department of Biophysics, Department of Cell and Developmental Biology, and Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109
| | - Kristen J Verhey
- Department of Biophysics, Department of Cell and Developmental Biology, and Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109 Department of Biophysics, Department of Cell and Developmental Biology, and Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109
| |
Collapse
|
48
|
Simm D, Hatje K, Kollmar M. Waggawagga: comparative visualization of coiled-coil predictions and detection of stable single α-helices (SAH domains). Bioinformatics 2014; 31:767-9. [PMID: 25338722 DOI: 10.1093/bioinformatics/btu700] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
UNLABELLED Waggawagga is a web-based tool for the comparative visualization of coiled-coil predictions and the detection of stable single α-helices (SAH domains). Overview schemes show the predicted coiled-coil regions found in the query sequence and provide sliders, which can be used to select segments for detailed helical wheel and helical net views. A window-based score has been developed to predict SAH domains. Export to several bitmap and vector graphics formats is supported. AVAILABILITY AND IMPLEMENTATION http://waggawagga.motorprotein.de
Collapse
Affiliation(s)
- Dominic Simm
- Department of NMR-based Structural Biology, Max-Planck-Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany
| | - Klas Hatje
- Department of NMR-based Structural Biology, Max-Planck-Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany
| | - Martin Kollmar
- Department of NMR-based Structural Biology, Max-Planck-Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany
| |
Collapse
|
49
|
Lu Q, Li J, Zhang M. Cargo recognition and cargo-mediated regulation of unconventional myosins. Acc Chem Res 2014; 47:3061-70. [PMID: 25230296 DOI: 10.1021/ar500216z] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Organized motions are hallmarks of living organisms. Such motions range from collective cell movements during development and muscle contractions at the macroscopic scale all the way down to cellular cargo (e.g., various biomolecules and organelles) transportation and mechanoforce sensing at more microscopic scales. Energy required for these biological motions is almost invariably provided by cellular chemical fuels in the form of nucleotide triphosphate. Biological systems have designed a group of nanoscale engines, known as molecular motors, to convert cellular chemical fuels into mechanical energy. Molecular motors come in various forms including cytoskeleton motors (myosin, kinesin, and dynein), nucleic-acid-based motors, cellular membrane-based rotary motors, and so on. The main focus of this Account is one subfamily of actin filament-based motors called unconventional myosins (other than muscle myosin II, the remaining myosins are collectively referred to as unconventional myosins). In general, myosins can use ATP to fuel two types of mechanomotions: dynamic tethering actin filaments with various cellular compartments or structures and actin filament-based intracellular transport. In contrast to rich knowledge accumulated over many decades on ATP hydrolyzing motor heads and their interactions with actin filaments, how various myosins recognize their specific cargoes and whether and how cargoes can in return regulate functions of motors are less understood. Nonetheless, a series of biochemical and structural investigations in the past few years, including works from our own laboratory, begin to shed lights on these latter questions. Some myosins (e.g., myosin-VI) can function both as cellular transporters and as mechanical tethers. To function as a processive transporter, myosins need to form dimers or multimers. To be a mechanical tether, a monomeric myosin is sufficient. It has been shown for myosin-VI that its cellular cargo proteins can play critical roles in determining the motor properties. Dab2, an adaptor protein linking endocytic vesicles with actin-filament-bound myosin-VI, can induce the motor to form a transport competent dimer. Such a cargo-mediated dimerization mechanism has also been observed in other myosins including myosin-V and myosin-VIIa. The tail domains of myosins are very diverse both in their lengths and protein domain compositions and thus enable motors to engage a broad range of different cellular cargoes. Remarkably, the cargo binding tail of one myosin alone often can bind to multiple distinct target proteins. A series of atomic structures of myosin-V/cargo complexes solved recently reveals that the globular cargo binding tail of the motor contains a number of nonoverlapping target recognition sites for binding to its cargoes including melanophilin, vesicle adaptors RILPL2, and vesicle-bound GTPase Rab11. The structures of the MyTH4-FERM tandems from myosin-VIIa and myosin-X in complex with their respective targets reveal that MyTH4 and FERM domains extensively interact with each other forming structural and functional supramodules in both motors and demonstrate that the structurally similar MyTH4-FERM tandems of the two motors display totally different target binding modes. These structural studies have also shed light on why numerous mutations found in these myosins can cause devastating human diseases such as deafness and blindness, intellectual disabilities, immune disorders, and diabetes.
Collapse
Affiliation(s)
- 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
| | - 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
| | - 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
| |
Collapse
|
50
|
Toepfer C, Sellers JR. Use of fluorescent techniques to study the in vitro movement of myosins. EXPERIENTIA SUPPLEMENTUM (2012) 2014; 105:193-210. [PMID: 25095996 PMCID: PMC4178934 DOI: 10.1007/978-3-0348-0856-9_9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Myosins are a large superfamily of actin-dependent molecule motors that carry out many functions in cells. Some myosins are cargo carriers that move processively along actin which means that a single molecule of myosin can take many ATP-dependent steps on actin per initial encounter. Other myosins are designed to work in large ensembles such as myosin thick filaments. In vitro motility assays are a powerful method for studying the function of myosins. These assays in general use small amounts of protein, are simple to implement, and can be done on microscopes commonly found in many laboratories. There are two basic versions of the assay which involve different geometries. In the sliding actin in vitro motility assay, myosin molecules are bound to a coverslip surface in a simply constructed microscopic flow chamber. Fluorescently labeled actin filaments are added to the flow chamber in the presence of ATP, and the movement of these actin filaments powered by the surface-bound myosins is observed. This assay has been used widely for a variety of myosins including both processive and non-processive ones. From this assay, one can easily measure the rate at which myosin is translocating actin. The single-molecule motility assay uses an inverted geometry compared to the sliding actin in vitro motility assay. It is most useful for processive myosins. Here, actin filaments are affixed to the coverslip surface. Fluorescently labeled single molecules of myosins (usually ones with processive kinetics) are introduced, and the movement of single molecules along the actin filaments is observed. This assay typically uses total internal reflection fluorescent (TIRF) microscopy to reduce the background signal arising from myosins in solution. From this assay, one can measure the velocity of movement, the frequency of movement, and the run length. If sufficient photons can be collected, one can use Gaussian fitting of the point spread function to determine the position of the labeled myosin to within a few nanometers which allows for measurement of the step size and the stepping kinetics. Together, these two assays are powerful tools to elucidate myosin function.
Collapse
Affiliation(s)
- Christopher Toepfer
- Laboratory of Molecular Physiology, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - James R. Sellers
- Laboratory of Molecular Physiology, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| |
Collapse
|