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Microtubule Structure
Published by Anonymous on 2007/9/28 (2635 reads)
1: Tanpakushitsu Kakusan Koso. 2006 May;51(6 Suppl):535-42.


[Structure and function of microtubule-associated proteins]

[Article in Japanese]

Kotani S, Matsusima K, Hisanaga S.

kotani-bio@kanagawa-u.ac.jp

Publication Types:
Review

PMID: 16719309 [PubMed - indexed for MEDLINE]

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2: Adv Protein Chem. 2005;71:299-344.


The structure of microtubule motor proteins.

Marx A, Müller J, Mandelkow E.

Max-Planck-Unit for Structural Molecular Biology; Notkestrasse 85, 22607 Hamburg, Germany.

Microtubules are the intracellular tracks for two classes of motor proteins: kinesins and dyneins. During the past few years, the motor domain structures of several kinesins from different organisms have been determined by X-ray crystallography. Compared with kinesins, dyneins are much larger proteins and attempts to crystallize them have failed so far. Structural information about these proteins comes mostly from electron microscopy. In this chapter, we mainly focus on the crystal structures of kinesin motor domains.

Publication Types:
Comparative Study
Review

PMID: 16230115 [PubMed - indexed for MEDLINE]

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3: Int Rev Cytol. 2004;239:179-272.


MAPping the eukaryotic tree of life: structure, function, and evolution of the MAP215/Dis1 family of microtubule-associated proteins.

Gard DL, Becker BE, Josh Romney S.

Department of Biology, University of Utah, Salt Lake City, Utah 84112-0840, USA.

The MAP215/Dis1 family of proteins is an evolutionarily ancient family of microtubule-associated proteins, with characterized members in all major kingdoms of eukaryotes, including fungi (Stu2 in S. cerevisiae, Dis1 and Alp14 in S. pombe), Dictyostelium (DdCP224), plants (Mor1 in A. thaliana and TMBP200 in N. tabaccum), and animals (Zyg9 in C. elegans, Msps in Drosophila, XMAP215 in Xenopus, and ch-TOG in humans). All MAP215/Dis1 proteins (with the exception of those in plants) localize to microtubule-organizing centers (MTOCs), including spindle pole bodies in yeast and centrosomes in animals, and all bind to microtubules in vitro and?or in vivo. Diverse roles in regulating microtubule assembly and organization have been proposed for individual family members, and a substantial body of evidence suggests that MAP215/Dis1-related proteins play critical roles in the assembly and function of the meiotic/mitotic spindles and/or cell division. An extensive search of public databases (including both EST and genome databases) identified partial sequences predicted to encode more than three dozen new members of the MAP215/Dis1 family, including putative MAP215/Dis1-related proteins in Giardia lamblia and four other protists, sixteen additional species of fungi, six plants, and twelve animals. The structure and function of MAP215/Dis1 proteins are discussed in relation to the evolution of this ancient family of microtubule-associated proteins.

Publication Types:
Research Support, U.S. Gov't, Non-P.H.S.
Review

PMID: 15464854 [PubMed - indexed for MEDLINE]

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4: Yakugaku Zasshi. 2000 Oct;120(10):875-89.


[Natural organic compounds that affect to microtubule functions: syntheses and structure-activity relationships of combretastatins, curacin A and their analogs as the colchicine-site ligands on tubulin]

[Article in Japanese]

Iwasaki S, Shirai R.

Kitasato Institute, Research Center for Biological Function, Tokyo, Japan.

Microtubules (MT) are cylindrical polymers of the protein tubulin (TN) alpha, beta-heterodimer, and are known to be the main component of spindles in mitotic apparatus of eucaryotic cells. MT are also involved in many other basic and essential cell functions. There are a number of natural and synthetic compounds that interfere with MT function to cause the mitotic arrest of eucaryotic cells. Such antimitotic agents show a broad biological activity, and can be used for medicinal and agrochemical purposes. On the other hand, they are important also as the biochemical tools for understanding the dynamics of MT network. Most of such antimitotic agents, with a few exceptions, bind to beta-TN. Among them, colchicine (CLC), vinblastine and taxol have played major roles in practical uses as well as in biochemical studies of MT functions. They all bind to beta-TN but their binding sites are different. We have worked on a variety of antimitotic agents that bind to either of colchicine-site, vinblastine-site and taxol-site, in discovery, structures, biological actions and/or interactions with TN. In this paper, the results of our studies on CLC-site ligands were summarized; (1) synthetic analogs of combretastatin A-4 (CBS A-4), isolated as a cytotoxic compound produced by a species of South African tree Combretum caffrum, (2) curacin A (CU-A), a cytotoxic metabolite of a marine cyanobacteria Lyngbya majuscula, and its related compounds. Interactions of these compounds with TN were studied and structure-activity relationships of these two classes of compounds were discussed.

Publication Types:
English Abstract
Review

PMID: 11082700 [PubMed - indexed for MEDLINE]

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5: Biol Cell. 1999 May-Jun;91(4-5):343-54.


Centrosome structure and microtubule nucleation in animal cells.

Tassin AM, Bornens M.

Institut Curie, Section Recherche, UMR 144 du CNRS, Paris, France.

Genetic studies in the budding yeast have led to the molecular characterization of gamma-tubulin associated proteins and to the identification of orthologues in animal cells. While the gamma-tubulin complex is more complex in animal cells than in budding yeast, its function is probably maintained throughout evolution. In this review we discuss some of the possible regulations of the nucleation activity in the light of the centrosome structure. A potential cross-talk between microtubule nucleation and centrosome duplication is suggested by some, still scarce, data.

Publication Types:
Review

PMID: 10519000 [PubMed - indexed for MEDLINE]

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6: Chem Biol. 1999 Mar;6(3):R65-9.


How Taxol stabilises microtubule structure.

Amos LA, Löwe J.

MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, UK. laa@mrc-lmb.cam.ac.uk

The structure of tubulin shows paclitaxel (Taxol(R)) binding to a pocket in beta tubulin on the microtubule's inner surface, which counteracts the effects of GTP hydrolysis occurring on the other side of the monomer.

Publication Types:
Review

PMID: 10074470 [PubMed - indexed for MEDLINE]

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7: Curr Opin Struct Biol. 1998 Dec;8(6):785-91.


Tubulin structure: insights into microtubule properties and functions.

Downing KH, Nogales E.

Donner Laboratory Life Science Division Lawrence Berkeley National Laboratory Molecular and Cell Biology University of California Berkely CA 94720 USA. khdowning@lbl.gov

The structure of tubulin has recently been determined by electron crystallography, paving the way for a clearer understanding of the unique properties of tubulin that allow its varied functions within the cell. Some of the ongoing work on tubulin can be interpreted in terms of its structure, which can serve to guide future studies.

Publication Types:
Review

PMID: 9914260 [PubMed - indexed for MEDLINE]

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8: Eur Biophys J. 1998;27(5):446-54.


Organisation and structure of microtubules and microtubule-motor protein complexes.

Wade RH, Meurer-Grob P, Metoz F, Arnal I.

Instiut de Biologie Structurale (CEA & CNRS), Grenoble, France.

We present a short overview of the current status of work on the organisation and structure of microtubules and of microtubule-motor protein complexes. At present there is great interest in obtaining structural information that can help us to understand the movement of the kinesin family of microtubule associated molecular motors. Using electron cryomicroscopy and image reconstruction methods three dimensional maps of microtubule-motor complexes have been obtained in the presence of different nucleotides. We address a number of principles involved in different aspects of this work.

Publication Types:
Research Support, Non-U.S. Gov't
Review

PMID: 9760726 [PubMed - indexed for MEDLINE]

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9: Biochim Biophys Acta. 1998 Aug 14;1404(1-2):113-26.


The role of microtubule-based motor proteins in maintaining the structure and function of the Golgi complex.

Burkhardt JK.

Department of Pathology, The University of Chicago, 5841 S. Maryland Ave. MC1089, Chicago, IL 60637, USA. jburkhar@flowcity.bsd.uchicago.edu

The intimate association between the Golgi complex and the microtubule cytoskeleton plays an important role in Golgi structure and function. Recent evidence indicates that the dynamic flow of material from the ER to the Golgi is crucial to maintaining the integrity of the Golgi complex and its characteristic location within the cell, and it is now clear that this flow is dependent on the ongoing activity of microtubule motor proteins. This review focuses primarily on recent microinjection and expression studies which have explored the role of individual microtubule motor proteins in controlling Golgi dynamics. The collective evidence shows that one or more isoforms of cytoplasmic dynein, together with its cofactor the dynactin complex, are required to maintain a juxtanuclear Golgi complex in fibroblasts. Although questions remain about how dynein and dynactin are linked to the Golgi, there is evidence that the Golgi-spectrin lattice is involved. Kinesin and kinesin-like proteins appear to play a smaller role in Golgi dynamics, though this may be very cell-type specific. Moreover, new evidence about the role of kinesin family members continues to emerge. Thanks in part to recent advances in our understanding of these molecular motors, our current view of the Golgi complex is of an organelle in flux, undergoing constant renewal. Future research will be aimed at elucidating how and to what extent these motor proteins function as regulators of Golgi function.

Publication Types:
Review

PMID: 9714769 [PubMed - indexed for MEDLINE]

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10: Curr Opin Cell Biol. 1998 Feb;10(1):16-22.


Tubulin and microtubule structure.

Downing KH, Nogales E.

Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA. KHDowning@lbl.gov

Our knowledge of microtubule structure and its relationship to microtubule function continue to grow. Cryo-electron microscopy has given us new images of the microtubule polymerization and depolymerization processes and of the interaction of these polymers with motor proteins. We now know more about the effect of nucleotide state on the structure and dynamic instability of microtubules. The atomic model of tubulin, very recently obtained by electron crystallography, is bringing new insight into the properties of this protein and its self-assembly into microtubules, and promises to inspire new experimental efforts that should lead us to an understanding of the microtubule system at the molecular level.

Publication Types:
Review

PMID: 9484591 [PubMed - indexed for MEDLINE]

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11: Curr Opin Cell Biol. 1997 Feb;9(1):12-7.


Microtubule structure and dynamics.

Wade RH, Hyman AA.

Institut de Biologie Structurale, 41 Avenue des Martyrs, 38027 Grenoble Cedex1, France.

The study of microtubules always manages to surprise and fascinate us, and it has done so yet again over the past year as significant progress has been made in the areas of microtubule nucleation, growth and structural polarity. Microtubule nucleation has been the subject of publications that show the involvement of gamma-tubulin-containing complexes as nucleating templates in the microtubule-organizing centre. It is unclear how this nucleation is compatible with microtubule growth, which appears to take place by an unusual, and perhaps unique, process involving sheet-like extensions that continuously close into tubes as growth proceeds. The related, and longstanding, problem is that of the relationship between tubulin dimer structure and microtubule polarity. This problem appears to be solved. A number of approaches have converged to suggest that the tubulin dimer is organized with beta-tubulin pointing towards the microtubule fast-growing plus end and with alpha-tubulin towards the minus end. Specific decoration with kinesin monomers shows that all microtubules examined to date are basically organized as B-lattices.

Publication Types:
Review

PMID: 9013674 [PubMed - indexed for MEDLINE]

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12: Curr Opin Cell Biol. 1997 Feb;9(1):4-11.


The structure of microtubule-motor complexes.

Amos LA, Hirose K.

Medical Research Council Laboratory of Molecular Biology, Medical Research Council, Centre Hills Road, Cambridge CB2 2QH, UK. laa@mrc-lmb.cam.ac.uk

New images, calculated from electron micrographs, show the three-dimensional structures of microtubules and tubulin sheets decorated stoichiometrically with globular motor protein domains (heads). Single heads of kinesin and ncd, the kinesin-related protein that moves in the reverse direction to kinesin, bind in the same way to the same site on tubulin. Dimeric kinesin and dimeric ncd show an interesting difference in the positions of their second heads.

Publication Types:
Review

PMID: 9013667 [PubMed - indexed for MEDLINE]

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13: Ann N Y Acad Sci. 1996 Jan 17;777:96-106.


Structure, microtubule interactions, and phosphorylation of tau protein.

Mandelkow EM, Schweers O, Drewes G, Biernat J, Gustke N, Trinczek B, Mandelkow E.

Max-Planck-Unit for Structural Molecular Biology, Hamburg, Germany. mand@mpasmb.desy.de

This paper summarizes recent structural and functional studies on tau protein, its interactions with microtubules, its self-assembly into paired helical filaments (PHF)-like fibers, and its modification by phosphorylation. The structure of tau in solution resembles that of a random coil. Both tau and Alzheimer PHFs have very little secondary structure, making it improbable that the assembly of tau into PHFs is based on interacting beta sheets. Tau's binding to microtubules can be described by a "jaws" effect. The domain containing the repeats binds very weakly, while the flanking regions (jaws) bind strongly, even without the repeats. However, only the combination of flanking regions and repeats makes binding productive in terms of microtubule nucleation and assembly. Although the majority of Alzheimer-like phosphorylation sites are outside the repeats they have only a weak influence on binding, whereas the phosphorylation at Ser262 inside the repeats inhibits binding and makes microtubules dynamically unstable. This site can be phosphorylated by kinases present in brain tissue, and it is uniquely phosphorylated in Alzheimer brain.

Publication Types:
Research Support, Non-U.S. Gov't
Review

PMID: 8624133 [PubMed - indexed for MEDLINE]

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14: Yakugaku Zasshi. 1994 Jul;114(7):435-47.


[Structure and function of mammalian brain microtubule-associated proteins]

[Article in Japanese]

Fujii T.

Department of Functional Polymer Science, Faculty of Textile Science and Technology, Shinshu University, Ueda, Japan.

Cytoplasmic microtubules are fibrous intracellular organelles found in almost all eukaryotic cells and play an important role in maintenance of cell shape, cell division, axonal transport, secretion and receptor activity. Besides tubulin dimers, microtubule proteins consist of several other components called MAPs which promote microtubule assembly and form long filamentous projection on the surface of the polymer. In mammalian brain, two classes of MAPs have been characterized; one is structural MAPs including MAP1 (1A and 1B), MAP2 (2A, 2B and 2C) and tau which function in the morphogenesis and maintenance of neural tissues and cells, and the other contains motor MAPs (kinesin and MAP1C) which are related to translocation of vesicles along microtubules in axon and to mitosis. The primary sequences of MAPs have been determined from their cDNAs. The functions of structural MAPs are modulated by their binding to other intracellular components, different expressions of isoforms during brain development and phosphorylation-dephosphorylation by various protein kinases and phosphatases. Biochemical characterization of MAP2 and tau have been well investigated. However, little is known about the function of MAP1 under the biochemical level, because MAP1 is unstable and high sensitive to proteases. We have developed a simple and rapid purification procedure for MAP1 using poly (L-aspartic acid) and taxol, and observed MAP1-F-actin interaction as well as MAP1-microtubules interaction. Recently, we have found that three specific kinases which can phosphorylate MAP1A and 1B are associated with MAP1 preparation and called it MAP1 kinase. Some evidence suggest that one of them is an unknown kinase and others are casein kinase I- and II-like kinases. Further studies to examine MAP1 kinase and phosphorylation of MAP1 provide a valuable insight for understanding thoroughly the microtubule-mediated functions.

Publication Types:
English Abstract
Review

PMID: 7932091 [PubMed - indexed for MEDLINE]

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15: Pharmacol Ther. 1991 Nov;52(2):159-71.


Resistance to antimitotic agents as genetic probes of microtubule structure and function.

Cabral F, Barlow SB.

Department of Pharmacology, University of Texas Medical School, Houston 77225.

Much of our knowledge about microtubules has come from detailed morphological, biochemical, and cell biological studies. As more is learned about these organelles, questions regarding the in vivo regulation of their expression and function become increasingly important. Genetics provides an approach to address these more subtle questions in the living cell. Mammalian mutants with microtubule alterations have been isolated using selections for resistance to the cytotoxic effects of a number of antimitotic drugs. A subset of these mutants have clearly defined alterations in alpha- or in beta-tubulin, and these have been used to explore the mechanisms by which mammalian cells acquire resistance to this class of drugs. In addition, the mutants are providing valuable insights into how tubulin expression is regulated, into what factors determine the extent of microtubule assembly in living cells, into the domains of tubulin that are involved in assembly, and into the role of microtubules in essential cellular processes.

Publication Types:
Research Support, U.S. Gov't, P.H.S.
Review

PMID: 1818334 [PubMed - indexed for MEDLINE]

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16: Int Rev Cytol. 1991;124:217-73.


Molecular structure and function of microtubule-associated proteins.

Wiche G, Oberkanins C, Himmler A.

Institut für Biochemie, Universität Wien, Vienna, Austria.

Publication Types:
Research Support, Non-U.S. Gov't
Review

PMID: 2001917 [PubMed - indexed for MEDLINE]

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17: Cell Motil Cytoskeleton. 1990;15(1):1-6.


The yeast microtubule cytoskeleton: genetic approaches to structure and function.

Stearns T.

Department of Biology, Massachusetts Institute of Technology, Cambridge.

Publication Types:
Review

PMID: 2403845 [PubMed - indexed for MEDLINE]

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18: Annu Rev Biophys Biophys Chem. 1985;14:161-88.


Pathway of the microtubule-dynein ATPase and the structure of dynein: a comparison with actomyosin.

Johnson KA.

Dynein and myosin show several important similarities in design as well as some interesting differences in detail. Both ATPases function as crossbridges that undergo microscopic movements to drive the sliding of filaments, which results in macroscopic movements. They share a common design employing globular heads attached to flexible strands. Each head contains one ATP-binding site and one filament-binding site, and the binding of ATP induces an extremely rapid dissociation of the crossbridge-filament "rigor" complex. Following ATP hydrolysis, which is readily reversible, the crossbridge reassociates with the filament and returns to its original state with the release of products. Thus, the nucleotide-induced changes in conformation are effectively used to couple the hydrolysis of ATP to the dissociation and reassociation of the crossbridge in order to produce a force for net movement according to the Lymn-Taylor-Eisenberg model. The utilization of nucleotide-binding energy to induce a change in conformation can be rationalized in terms of our understanding of enzyme catalysis in general, whereby substrate binding energy is used to induce a change in conformation that stabilizes the transition state for catalysis. In these crossbridge ATPases, the substrate-induced change in conformation also serves to weaken the crossbridge-filament interaction. The pathway is symmetrical, with a return to the tight (filament) binding state coupled to product release. The ball on a string design may provide a reasonable basis to explain how a unidirectional force is obtained from a symmetrical cycle; opposite changes in conformation with the binding and release of the nucleotide produce a significant force only when pulling on the flexible strand. Moreover, the very rapid dissociation of the crossbridge following ATP binding limits the time that a negative force is in effect and also prevents a rigor crossbridge from retarding the sliding movements generated by other crossbridges. Myosin and dynein exhibit nearly identical kinetic constants governing ATP binding and the ATP-induced dissociation of the crossbridge. These appear as invariant steps that may reflect the basic principles of enzyme catalysis as applied to the mechanochemical cycle. The rates of ATP hydrolysis and synthesis by myosin and dynein differ slightly, but in each case the reactions are readily reversible with an equilibrium constant less than one. Steps involving the loss and rebinding of products occur at rates two to three orders of magnitude faster for dynein than for myosin.(ABSTRACT TRUNCATED AT 400 WORDS)

Publication Types:
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, P.H.S.
Review

PMID: 3159394 [PubMed - indexed for MEDLINE]

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19: Usp Sovrem Biol. 1982 Nov-Dec;94(3):360-75.


[Structure of the microtubule organizational centers from the comparative evolutionary aspect]

[Article in Russian]

Onishchenko GE.

Publication Types:
Comparative Study
Review

PMID: 6186098 [PubMed - indexed for MEDLINE]

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