DOCSLIB.ORG

Kinesins at a Glance Sharyn A

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Kinesins at a Glance Sharyn A Erratum Kinesins at a glance Sharyn A. Endow, F. Jon Kull and Honglei Liu Journal of Cell Science 123, 4000 © 2010. Published by The Company of Biologists Ltd doi:10.1242/jcs.082667doi:10. There was an error published in J. Cell Sci. 123, 3420-3423. We misprinted the sentence in the acknowledgements that states the American Heart Association (AHA) as the funding body supporting F. Jon Kull. The correct sentence is given below: The authors’ research on kinesins is supported by NIH GM046225 and March of Dimes 1-FY07-443 Grants to S.A.E., and AHA Scientist Development Grant 0330345N to F.J.K. We apologise for this mistake. 3420 Cell Science at a Glance Kinesins at a glance Kinesin was discovered in 1985 – 25 years ago – into the public databases (Yang et al., 1989). The based on its motility in cytoplasm extruded predicted KHC protein contained a motor Sharyn A. Endow1,*, F. Jon Kull2 from the giant axon of the squid (Allen et al., domain with ATP- and microtubule-binding and Honglei Liu1 1982; Brady et al., 1982; Vale et al., 1985). The sites, an -helical coiled-coil dimerization 1Department of Cell Biology, Duke University Medical purified protein, now known as kinesin-1, domain (also referred to as the stalk), and a tail Center, Durham, NC 27710, USA consisted of two heavy chains with motor that can interact with vesicles or organelles 2 Department of Chemistry, Dartmouth College, New activity that were associated with two light through light chains. A large number of kinesin- Hanover, NH 03755, USA *Author for correspondence ([email protected]) chains, which mediate motor binding to vesicles related proteins were identified in rapid and other cargo. Vesicle movement was distal to succession by sequence homology to Drosophila Journal of Cell Science 123, 3420-3424 © 2010. Published by The Company of Biologists Ltd the cell body, towards microtubule plus ends, KHC. They included the first kinesin-14 doi:10.1242/jcs.064113 consistent with the proposal that the motor was proteins, which, despite their sequence the basis of fast axonal transport (Allen et al., homology to kinesin-1, were subsequently This article is part of a Minifocus on microtubule 1982; Brady et al., 1982). demonstrated to be minus-end motors. Screens dynamics. For further reading, please see related For several years, kinesin-1 was the only for kinesins, on the basis of conserved protein articles: ‘Microtubule plus-end tracking proteins motor protein known that moved on motifs, revealed a large number of kinesin- (+TIPs)’ by Anna Akhmanova and Michel O. Steinmetz (J. Cell Sci. 123, 3415-3419), ‘Tubulin microtubules towards their plus ends, the related proteins in a given organism – as many as depolymerization may be an ancient biological motor opposite direction the previously discovered ~50 in human – each containing a highly process’ by J. Richard McIntosh et al. (J. Cell Sci. 123, 3425-3434), ‘Towards a quantitative understanding of axonemal dyneins move. Strikingly, many conserved motor domain that identified the mitotic spindle assembly and mechanics’ by Alex kinesin-related proteins were reported in the protein as a kinesin family member. Mogilner and Erin Craig (J. Cell Sci. 123, 3435-3445) early 1990s, soon after the first sequence of a Phylogenetic analysis defined groups within and ‘Post-translational modifications of microtubules’ by Dorota Wloga and Jacek Gaertig (J. Cell Sci. 123, gene encoding a kinesin-1 heavy chain, the kinesin family that perform similar cellular pp. 3447-3455). Drosophila melanogaster Khc, was deposited functions in different cells or organisms (Kim Journal of Cell Science (See poster insert) Journal of Cell Science 123 (20) 3421 and Endow, 2000). A standardized system of microtubules. Kinesin-5, a homotetrameric side, a design conserved in the myosins (Kull et kinesin nomenclature was introduced in 2004, motor, contains a stalk formed by interactions al., 1996; Sablin et al., 1996). The nucleotide- renaming the groups by number (Lawrence et between the coiled coils of two anti-parallel binding cleft on one side of the central -sheet al., 2004). There are currently 14 groups and dimers (Tao et al., 2006); the motor can bind by contains a highly conserved GQTGSGKT many ungrouped or orphan kinesins. Among its heads to different microtubules to crosslink motif that forms the P-loop. The microtubule- these, three kinesins – kinesin-1, kinesin-14 and and slide microtubules in mitosis. binding site on the opposite side includes the kinesin-13 – highlight the diverse structure and Other kinesins dimerize dynamically by structural elements L11-4-L12-5, which function of the family. coiled-coil stalk formation, thereby regulating interact with tubulin and undergo movement motor activity. C. elegans kinesin-3 Unc104 between the ADP and ATP states. The motor Kinesin diversity exists as a monomer, but, remarkably, forms contains highly conserved switch I (SSRSH) Kinesin-1, the first-discovered kinesin, has been dimers with velocities much faster than kinesin- and II (DLAGSE) motifs, which change in studied extensively. The development of single- 1 (Tomishige et al., 2002). The monomer neck – conformation during the ATP hydrolysis cycle, molecule assays and the early finding that single the region of the stalk adjacent to the head – can similar to their counterparts in G-proteins kinesin-1 molecules move processively along inhibit dimerizaton by folding back onto itself (Rice et al., 1999; Yun et al., 2001; Hirose et microtubules (Howard et al., 1989) made it (Al-Bassam et al., 2003). Unc104 binds to lipid al., 2006). Switch I and II form a salt-bridge possible to measure the steps and force produced membranes and can dimerize when clustered in that, in myosin, closes the nucleotide-binding by single motors. Mutant analysis showed that rafts (Klopfenstein et al., 2002). cleft, enabling the motor to hydrolyze ATP kinesin-1 has an essential role in vesicle Some kinesins associate with different (Geeves and Holmes, 1999). The closed transport in neuronal cells (Saxton et al., 1991). proteins through a coiled-coil stalk. For conformation has now been seen in a crystal Homologs have been found in a wide range of example, two different kinesin proteins dimerize structure of frog kinesin-5 Eg5 bound to AMP- organisms: from yeast, Caenorhabditis elegans and associate with a non-motor protein to form PNP (a nonhydrolyzable ATP analog) (Parke et and Drosophila, to the mouse and human. hetereotrimeric kinesin-2 (Cole et al., 1993); al., 2010). Two other kinesins – Ncd, a Drosophila budding yeast kinesin-14 Kar3, however, can The motor domain is structurally conserved kinesin-14, and MCAK, a Chinese hamster dimerize either with itself or with two non- among the kinesin proteins; differences in kinesin-13 – have been widely studied because motor proteins, Vik1 and Cik1 (Manning et al., motility and cellular function are largely due to of their distinct motor properties. Ncd was the 1999; Barrett et al., 2000). Dimerization with regions outside the catalytic core. Motor first minus-end kinesin motor reported (Walker Cik1 alters Kar3 structurally and converts it into directionality is determined by the region et al., 1990; McDonald et al., 1990) and has a faster motor (Chu et al., 2005). Strikingly, the adjacent to the motor core, the kinesin-1 neck provided crucial information regarding motor Vik1 C-terminal globular domain contains a linker or Ncd neck (Endow, 1999). The directionality and the mechanism of kinesin fold similar to the kinesin catalytic core, kinesin-1 neck linker connects the head to function. MCAK was identified in an antibody although it lacks an ATP-binding cleft the stalk (Kozielski et al., 1997) and has been screen for kinesins and shown to be a (Allingham et al., 2007). proposed to dock onto the motor core in the ATP centromere-associated protein (Wordeman and The tail binds to cellular cargo and is state and undock after hydrolysis, producing Mitchison, 1995). Subsequent studies resulted important for transport, but has been less well force to drive motor movement along Journal of Cell Science in the provocative finding that the motor is studied than the head and stalk. Kinesin-1 microtubules (Rice et al., 1999). Although neck targeted to microtubule ends where it removes binding to vesicles and organelles can occur linker docking has been observed in crystal tubulin dimers, destabilizing microtubules and through light chains that exist in different structures, its role in generating force has been regulating microtubule dynamics (Desai et al., isoforms and arise by alternative splicing (Cyr controversial because it occurs with a small free 1999; Wordeman, 2010; Ems-McClung and et al., 1991), although adaptor or scaffold energy change (Rice et al., 2003). Recently, the Walczak, 2010). proteins have now been identified that bind ‘cover strand’, a structural element at the N- kinesins to cargo (Hirokawa et al., 2009). For terminus of the motor, has been proposed to Kinesin structural organization and example, the adaptor protein Milton mediates dock onto the catalytic domain together with the regulation kinesin-1 binding to mitochondria, which is neck linker to drive kinesin-1 steps along All kinesins contain a motor domain – the head – inhibited by Ca2+. Further molecules are being microtubules (Hwang et al., 2008). This usually attached to a stalk and tail, but the discovered that facilitate kinesin-1 binding to hypothesis is supported by mutant analysis position of the head varies – it is at the N- endosomes, vesicles and organelles (Hirokawa showing that the cover strand is essential for terminus of kinesin-1, C-terminus of kinesin-14 et al., 2009). Other kinesins, such as kinesin-14 kinesin-1 motility (Khalil et al., 2008). and centrally located in kinesin-13 (Kim and Ncd, bind to microtubules by their tails, as well Ncd and other kinesin-14 motors lack a neck Endow, 2000).
Load more

Recommended publications
  • Mechanical Design of Translocating Motor Proteins
    Cell Biochem Biophys (2009) 54:11–22 DOI 10.1007/s12013-009-9049-4 REVIEW PAPER Mechanical Design of Translocating Motor Proteins Wonmuk Hwang Æ Matthew J. Lang Published online: 19 May 2009 Ó Humana Press Inc. 2009 Abstract Translocating motors generate force and move Introduction along a biofilament track to achieve diverse functions including gene transcription, translation, intracellular cargo Motor proteins form distinct classes in the protein universe transport, protein degradation, and muscle contraction. as they can convert chemical energy directly into mechan- Advances in single molecule manipulation experiments, ical work. Among them, translocating motors move along structural biology, and computational analysis are making biopolymer tracks, such as nucleic acids, polypeptides, or it possible to consider common mechanical design princi- quaternary biofilament structures like F-actin or microtu- ples of these diverse families of motors. Here, we propose a bule (Kolomeisky and Fisher proposed the term ‘‘translo- mechanical parts list that include track, energy conversion case’’ for these motors [41]. However, we prefer to use machinery, and moving parts. Energy is supplied not just ‘‘translocating motor,’’ since translocase refers to mem- by burning of a fuel molecule, but there are other sources brane-bound motors such as SecA, whose function is to or sinks of free energy, by binding and release of a fuel or translocate a protein across the membrane [24]). Movement products, or similarly between the motor and the track. is an essential part of their function. For example, RNA Dynamic conformational changes of the motor domain can polymerase (RNAP) walks along the DNA molecule and be regarded as controlling the flow of free energy to and transcribes the genetic code into RNA [25].
    [Show full text]
  • Kinesin-4 KIF21B Limits Microtubule Growth to Allow Rapid Centrosome
    RESEARCH ARTICLE Kinesin-4 KIF21B limits microtubule growth to allow rapid centrosome polarization in T cells Peter Jan Hooikaas1†, Hugo GJ Damstra1†, Oane J Gros1, Wilhelmina E van Riel1‡, Maud Martin1§, Yesper TH Smits2, Jorg van Loosdregt2, Lukas C Kapitein1, Florian Berger1*, Anna Akhmanova1* 1Cell Biology, Neurobiology and Biophysics, Department of Biology, Faculty of Science, Utrecht University, Utrecht, Netherlands; 2Center for Translational Immunology, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands Abstract When a T cell and an antigen-presenting cell form an immunological synapse, rapid dynein-driven translocation of the centrosome toward the contact site leads to reorganization of microtubules and associated organelles. Currently, little is known about how the regulation of *For correspondence: microtubule dynamics contributes to this process. Here, we show that the knockout of KIF21B, a [email protected] (FB); kinesin-4 linked to autoimmune disorders, causes microtubule overgrowth and perturbs [email protected] (AA) centrosome translocation. KIF21B restricts microtubule length by inducing microtubule pausing typically followed by catastrophe. Catastrophe induction with vinblastine prevented microtubule †These authors contributed overgrowth and was sufficient to rescue centrosome polarization in KIF21B-knockout cells. equally to this work Biophysical simulations showed that a relatively small number of KIF21B molecules can restrict ‡ Present address: Netherlands mirotubule length and promote an imbalance
    [Show full text]
  • Theory of Cytoskeletal Reorganization During Crosslinker-Mediated Mitotic Spindle Assembly
    bioRxiv preprint doi: https://doi.org/10.1101/419135; this version posted March 1, 2019. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. Theory of cytoskeletal reorganization during crosslinker-mediated mitotic spindle assembly A. R. Lamson, C. J. Edelmaier, M. A. Glaser, and M. D. Betterton Abstract Cells grow, move, and respond to outside stimuli by large-scale cytoskeletal reorganization. A prototypical example of cytoskeletal remodeling is mitotic spindle assembly, during which micro- tubules nucleate, undergo dynamic instability, bundle, and organize into a bipolar spindle. Key mech- anisms of this process include regulated filament polymerization, crosslinking, and motor-protein activity. Remarkably, using passive crosslinkers, fission yeast can assemble a bipolar spindle in the absence of motor proteins. We develop a torque-balance model that describes this reorganization due to dynamic microtubule bundles, spindle-pole bodies, the nuclear envelope, and passive crosslink- ers to predict spindle-assembly dynamics. We compare these results to those obtained with kinetic Monte Carlo-Brownian dynamics simulations, which include crosslinker-binding kinetics and other stochastic effects. Our results show that rapid crosslinker reorganization to microtubule overlaps facilitates crosslinker-driven spindle assembly, a testable prediction for future experiments. Combin- ing these two modeling techniques, we illustrate a general method for studying cytoskeletal network reorganization. 1 bioRxiv preprint doi: https://doi.org/10.1101/419135; this version posted March 1, 2019. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved.
    [Show full text]
  • Construction and Loss of Bacterial Flagellar Filaments
    biomolecules Review Construction and Loss of Bacterial Flagellar Filaments Xiang-Yu Zhuang and Chien-Jung Lo * Department of Physics and Graduate Institute of Biophysics, National Central University, Taoyuan City 32001, Taiwan; [email protected] * Correspondence: [email protected] Received: 31 July 2020; Accepted: 4 November 2020; Published: 9 November 2020 Abstract: The bacterial flagellar filament is an extracellular tubular protein structure that acts as a propeller for bacterial swimming motility. It is connected to the membrane-anchored rotary bacterial flagellar motor through a short hook. The bacterial flagellar filament consists of approximately 20,000 flagellins and can be several micrometers long. In this article, we reviewed the experimental works and models of flagellar filament construction and the recent findings of flagellar filament ejection during the cell cycle. The length-dependent decay of flagellar filament growth data supports the injection-diffusion model. The decay of flagellar growth rate is due to reduced transportation of long-distance diffusion and jamming. However, the filament is not a permeant structure. Several bacterial species actively abandon their flagella under starvation. Flagellum is disassembled when the rod is broken, resulting in an ejection of the filament with a partial rod and hook. The inner membrane component is then diffused on the membrane before further breakdown. These new findings open a new field of bacterial macro-molecule assembly, disassembly, and signal transduction. Keywords: self-assembly; injection-diffusion model; flagellar ejection 1. Introduction Since Antonie van Leeuwenhoek observed animalcules by using his single-lens microscope in the 18th century, we have entered a new era of microbiology.
    [Show full text]
  • Review of Molecular Motors
    REVIEWS CYTOSKELETAL MOTORS Moving into the cell: single-molecule studies of molecular motors in complex environments Claudia Veigel*‡ and Christoph F. Schmidt§ Abstract | Much has been learned in the past decades about molecular force generation. Single-molecule techniques, such as atomic force microscopy, single-molecule fluorescence microscopy and optical tweezers, have been key in resolving the mechanisms behind the power strokes, ‘processive’ steps and forces of cytoskeletal motors. However, it remains unclear how single force generators are integrated into composite mechanical machines in cells to generate complex functions such as mitosis, locomotion, intracellular transport or mechanical sensory transduction. Using dynamic single-molecule techniques to track, manipulate and probe cytoskeletal motor proteins will be crucial in providing new insights. Molecular motors are machines that convert free energy, data suggest that during the force-generating confor- mostly obtained from ATP hydrolysis, into mechanical mational change, known as the power stroke, the lever work. The cytoskeletal motor proteins of the myosin and arm of myosins8,11 rotates around its base at the catalytic kinesin families, which interact with actin filaments and domain11–17, which can cause the displacement of bound microtubules, respectively, are the best understood. Less cargo by several nanometres18 (FIG. 1B). In kinesins, the is known about the dynein family of cytoskeletal motors, switching of the neck linker (~13 amino acids connecting which interact with microtubules. Cytoskeletal motors the catalytic core to the cargo-binding stalk domain) from power diverse forms of motility, ranging from the move- an ‘undocked’ state to a state in which it is ‘docked’ to the ment of entire cells (as occurs in muscular contraction catalytic domain, is the equivalent of the myosin power or cell locomotion) to intracellular structural dynamics stroke10.
    [Show full text]
  • A Standardized Kinesin Nomenclature • Lawrence Et Al
    JCB: COMMENT A standardized kinesin nomenclature Carolyn J. Lawrence,1 R. Kelly Dawe,1,2 Karen R. Christie,3,4 Don W. Cleveland,3,5 Scott C. Dawson,3,6 Sharyn A. Endow,3,7 Lawrence S.B. Goldstein,3,8 Holly V. Goodson,3,9 Nobutaka Hirokawa,3,10 Jonathon Howard,3,11 Russell L. Malmberg,1,3 J. Richard McIntosh,3,12 Harukata Miki,3,10 Timothy J. Mitchison,3,13 Yasushi Okada,3,10 Anireddy S.N. Reddy,3,14 William M. Saxton,3,15 Manfred Schliwa,3,16 Jonathan M. Scholey,3,17 Ronald D. Vale,3,18 Claire E. Walczak,3,19 and Linda Wordeman3,20 1Department of Plant Biology, The University of Georgia, Athens, GA 30602 2Department of Genetics, The University of Georgia, Athens, GA 30602 3These authors contributed equally to this work and are listed alphabetically 4Department of Genetics, School of Medicine, Stanford University, Stanford, CA 94305 5Ludwig Institute for Cancer Research, 3080 CMM-East, 9500 Gilman Drive, La Jolla, CA 92093 6Department of Molecular and Cellular Biology, University of California, Berkeley, CA 94720 7Department of Cell Biology, Duke University Medical Center, Durham, NC 27710 8Department of Cellular and Molecular Medicine, Howard Hughes Medical Institute, School of Medicine, University of California, San Diego, La Jolla, CA 92093 9Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46628 10Department of Cell Biology and Anatomy, University of Tokyo, Graduate School of Medicine, Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan 11Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany 12Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder, CO 80309 13Institute for Chemistry and Cell Biology, Harvard Medical School, Boston, MA 02115 Downloaded from 14Department of Biology and Program in Cell and Molecular Biology, Colorado State University, Fort Collins, CO 80523 15Department of Biology, Indiana University, Bloomington, IN 47405 16Adolf-Butenandt-Institut, Zellbiologie, University of Munich, Schillerstr.
    [Show full text]
  • Cell Architecture: Putting the Building Blocks Together
    COCEBI-1090; NO. OF PAGES 3 Available online at www.sciencedirect.com Cell architecture: putting the building blocks together Editorial overview Anna Akhmanova and Tim Stearns Current Opinion in Cell Biology 2012, 25:xx–yy 0955-0674/$ – see front matter, # 2012 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.ceb.2012.12.003 Anna Akhmanova Cell Biology, Faculty of Science, Utrecht In considering cell architecture it is important to realize that for cells, as for University, Padualaan 8, 3584 CH Utrecht, buildings, the underpinning for the external shape is provided by a complex The Netherlands internal superstructure. And for cells, this cytoskeletal underpinning must e-mail: [email protected] be highly dynamic to effect the changes in morphology and organization associated with division, growth and differentiation. Cytoskeletal elements Anna Akhmanova is Professor of Cell Biology at Utrecht University, the Netherlands, and a were some of the first components of intracellular structure described by member of EMBO. Her lab uses cell early microscopists in the late 19th century, but it was not until a century biological approaches, in vitro reconstitutions later that the remarkable complexity of the cytoskeleton, in both compo- and high-resolution microscopy to study sition and behavior, has been revealed. Advances in genomics and proteo- molecular mechanisms of microtubule mics have provided us with near-comprehensive lists of the molecular dynamics and vesicle trafficking and their players associated with the various cytoskeletal systems. The challenge contribution to mammalian development and human disease. now is to understand how these components work together, and this is one of the central themes of this issue of Current Opinion in Cell Biology.
    [Show full text]
  • Tension on the Linker Gates the ATP-Dependent Release of Dynein from Microtubules
    ARTICLE Received 4 Apr 2014 | Accepted 3 Jul 2014 | Published 11 Aug 2014 DOI: 10.1038/ncomms5587 Tension on the linker gates the ATP-dependent release of dynein from microtubules Frank B. Cleary1, Mark A. Dewitt1, Thomas Bilyard2, Zaw Min Htet2, Vladislav Belyy1, Danna D. Chan2, Amy Y. Chang2 & Ahmet Yildiz2 Cytoplasmic dynein is a dimeric motor that transports intracellular cargoes towards the minus end of microtubules (MTs). In contrast to other processive motors, stepping of the dynein motor domains (heads) is not precisely coordinated. Therefore, the mechanism of dynein processivity remains unclear. Here, by engineering the mechanical and catalytic properties of the motor, we show that dynein processivity minimally requires a single active head and a second inert MT-binding domain. Processivity arises from a high ratio of MT-bound to unbound time, and not from interhead communication. In addition, nucleotide-dependent microtubule release is gated by tension on the linker domain. Intramolecular tension sensing is observed in dynein’s stepping motion at high interhead separations. On the basis of these results, we propose a quantitative model for the stepping characteristics of dynein and its response to chemical and mechanical perturbation. 1 Biophysics Graduate Group, University of California, Berkeley, California 94720, USA. 2 Department of Physics, University of California, Berkeley, California 94720, USA. Correspondence and requests for materials should be addressed to A.Y. (email: [email protected]). NATURE COMMUNICATIONS | 5:4587 | DOI: 10.1038/ncomms5587 | www.nature.com/naturecommunications 1 & 2014 Macmillan Publishers Limited. All rights reserved. ARTICLE NATURE COMMUNICATIONS | DOI: 10.1038/ncomms5587 ytoplasmic dynein is responsible for nearly all microtubule dynein’s MT-binding domain (MTBD) is located at the end of a (MT) minus-end-directed transport in eukaryotes1.In coiled-coil stalk10.
    [Show full text]
  • EMBO Facts & Figures
    excellence in life sciences Reykjavik Helsinki Oslo Stockholm Tallinn EMBO facts & figures & EMBO facts Copenhagen Dublin Amsterdam Berlin Warsaw London Brussels Prague Luxembourg Paris Vienna Bratislava Budapest Bern Ljubljana Zagreb Rome Madrid Ankara Lisbon Athens Jerusalem EMBO facts & figures HIGHLIGHTS CONTACT EMBO & EMBC EMBO Long-Term Fellowships Five Advanced Fellows are selected (page ). Long-Term and Short-Term Fellowships are awarded. The Fellows’ EMBO Young Investigators Meeting is held in Heidelberg in June . EMBO Installation Grants New EMBO Members & EMBO elects new members (page ), selects Young EMBO Women in Science Young Investigators Investigators (page ) and eight Installation Grantees Gerlind Wallon EMBO Scientific Publications (page ). Programme Manager Bernd Pulverer S Maria Leptin Deputy Director Head A EMBO Science Policy Issues report on quotas in academia to assure gender balance. R EMBO Director + + A Conducts workshops on emerging biotechnologies and on H T cognitive genomics. Gives invited talks at US National Academy E IC of Sciences, International Summit on Human Genome Editing, I H 5 D MAN 201 O N Washington, DC.; World Congress on Research Integrity, Rio de A M Janeiro; International Scienti c Advisory Board for the Centre for Eilish Craddock IT 2 015 Mammalian Synthetic Biology, Edinburgh. Personal Assistant to EMBO Fellowships EMBO Scientific Publications EMBO Gold Medal Sarah Teichmann and Ido Amit receive the EMBO Gold the EMBO Director David del Álamo Thomas Lemberger Medal (page ). + Programme Manager Deputy Head EMBO Global Activities India and Singapore sign agreements to become EMBC Associate + + Member States. EMBO Courses & Workshops More than , participants from countries attend 6th scienti c events (page ); participants attend EMBO Laboratory Management Courses (page ); rst online course EMBO Courses & Workshops recorded in collaboration with iBiology.
    [Show full text]
  • Single-Molecule Analysis of a Novel Kinesin Motor Protein
    Single-Molecule Analysis of a Novel Kinesin Motor Protein Jeremy Meinke Advisor: Dr. Weihong Qiu Oregon State University, Department of Physics June 7, 2017 Abstract Kinesins are intracellular motor proteins that transform chemical energy into mechanical energy through ATP hydrolysis to move along microtubules. Kinesin roles can vary among transportation, regulation, and spindle alignment within most cells. Many kinesin have been found to move towards the plus end of microtubules at a steady velocity. For this experiment, we investigate BimC - a kinesin-5 as- sociated with mitotic spindle regulation - under high salt conditions. Using single molecule imaging with Total Internal Reflection Fluorescence Microscopy, we found BimC to be directed towards the minus end of microtubules at a high velocity of 597±214 nm/s (mean±S.D, n=124). BimC then joins the few other kinesin found so far to be minus-end-directed. However, preliminary results at low salt condi- tions suggest that BimC switches towards the plus end. BimC could very well be an early example of a kinesin motor protein that is directionally-dependent upon ionic strength. These results suggest multiple branches of further investigation into directionally-dependent kinesin proteins and what purposes they might have. Contents 1 Introduction 1 1.1 Kinesin Proteins . 1 1.2 Total Internal Reflection Fluorescence Microscopy . 3 1.3 Protein Motion Analysis . 3 2 Methods 5 2.1 Design, Expression, and Purification of BimC . 5 2.2 Single Molecule Imaging . 7 2.3 Analysis of Data/Results . 7 3 Results 9 3.1 Single Molecule Imaging of BimC . 9 3.2 Directionality of BimC in High Salt Conditions .
    [Show full text]
  • 3053.Full.Pdf
    The Journal of Neuroscience, April 1995, 75(4): 3053-3064 The Activation of Protein Kinase A Pathway Selectively Inhibits Anterograde Axonal Transport of Vesicles but Not Mitochondria Transport or Retrograde Transport ~II viva Yasushi Okada, Reiko Sato-Yoshitake, and Nobutaka Hirokawa Department of Anatomy and Cell Biology, Faculty of Medicine, University of Tokyo, Hongo, Tokyo, 113, Japan To shed light on how axonal transport is regulated, we ex- is an especially well developed intracellular organelle transport amined the possible roles of protein kinase A (PKA) in viva system. Many studies have been focused on the mechanismof suggested by our previous work (Sato-Yoshitake et al., this transport, but little is known about its regulation. As a pu- 1992). Pharmacological probes or the purified catalytic tative mechanismfor the regulation, we have proposeda model subunit of PKA were applied to the permeabilized-reacti- from our recent studies (Hirokawa et al., 1990, 1991) that the vated model of crayfish walking leg giant axon, and the anterogrademotor kinesin is decommissionedat the axon ter- effect was monitored by the quantitative video-enhanced minal, and that the retrogrademotor cytoplasmic dynein is trans- light microscopy and the quantitative electron microscopy. ported, presumably in an inactive form, by the anterogradeor- Dibutyryl cyclic AMP caused concentration-dependent ganelle transport to the axon terminal, where it should be transient reduction in the number of anterogradely trans- activated to support the retrograde organelle transport. ported small vesicles, while the retrogradely transported Our present study was undertakento examine this regulation organelles and anterogradely transported mitochondria mechanism.One plausiblemechanism is through protein kinases showed no decrease.
    [Show full text]
  • Motor-Driven Dynamics in Actin-Myosin Networks Loïc Le Goff, François Amblard, Eric Furst
    Motor-Driven Dynamics in Actin-Myosin Networks Loïc Le Goff, François Amblard, Eric Furst To cite this version: Loïc Le Goff, François Amblard, Eric Furst. Motor-Driven Dynamics in Actin-Myosin Networks. Physical Review Letters, American Physical Society, 2001, 88 (1), pp.018101. 10.1103/phys- revlett.88.018101. hal-02415553 HAL Id: hal-02415553 https://hal.archives-ouvertes.fr/hal-02415553 Submitted on 19 Dec 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. VOLUME 88, NUMBER 1PHYSICALREVIEWLETTERS7JANUARY 2002 Motor-Driven Dynamics in Actin-Myosin Networks Loïc Le Goff, François Amblard,* and Eric M. Furst† Institut Curie, Physico-Chimie Curie, UMR CNRS/IC 168, 26 rue d’Ulm, 75248 Paris Cedex 05, France (Received 29 May 2001; published 14 December 2001) The effect of myosin motor protein activity on the filamentous actin (F-actin) rheological response is studied using diffusing wave spectroscopy. Under conditions of saturating motor activity, we find an enhancement of longitudinal filament fluctuations corresponding to a scaling of the viscoelastic shear 7͞8 modulus Gd͑v͒ϳv . As the adenosine tri-phosphate reservoir sustaining motor activity is depleted, we find an abrupt transient to a passive, “rigor state” and a return to dissipation dominated by transverse filament modes.
    [Show full text]