Academic literature on the topic 'Tubulin dimer'

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Journal articles on the topic "Tubulin dimer"

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Inclan, Y. F., and E. Nogales. "Structural models for the self-assembly and microtubule interactions of gamma-, delta- and epsilon-tubulin." Journal of Cell Science 114, no. 2 (January 15, 2001): 413–22. http://dx.doi.org/10.1242/jcs.114.2.413.

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alphabeta-tubulin heterodimers self-assemble to form microtubules nucleated by gamma-tubulin in the cell. Gamma-tubulin is believed to recruit the alphabeta-tubulin dimers that form the minus ends of microtubules, but the molecular mechanism of this action remains a matter of heated controversy. Still less is known about the function and molecular interactions of delta-tubulin and epsilon-tubulin. delta-tubulin may seed the formation of the C triplet tubules in the basal bodies of Chlamydomonas and epsilon-tubulin is known to localize to the centrosome in a cell cycle-dependent manner. Using the structure of alphabeta tubulin as a model, we have analyzed the sequences of gamma-, delta- and epsilon-tubulin in regions corresponding to different polymerization interfaces in the tubulin alphabeta dimer. The sequence comparisons sometimes show clear conservation, pointing to similar types of contacts being functionally important for the new tubulin considered. Conversely, certain surfaces show marked differences that rule out equivalent interactions for non-microtubular tubulins. This sequence/structure analysis has led us to structural models of how these special tubulins may be involved in protein-protein contacts that affect microtubule self-assembly. delta-tubulin most likely interacts longitudinally with alpha-tubulin at the minus ends of microtubules, while epsilon-tubulin most likely binds to the plus end of beta-tubulin. Conservation of key residues in gamma-tubulin suggests that it is capable of longitudinal self-assembly. The implications for the protofilament and template models of nucleation are considered.
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Caplow, Michael, and Lanette Fee. "Dissociation of the Tubulin Dimer Is Extremely Slow, Thermodynamically Very Unfavorable, and Reversible in the Absence of an Energy Source." Molecular Biology of the Cell 13, no. 6 (June 2002): 2120–31. http://dx.doi.org/10.1091/mbc.e01-10-0089.

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The finding that exchange of tubulin subunits between tubulin dimers (α-β + α′β′ ↔ α′β + αβ′) does not occur in the absence of protein cofactors and GTP hydrolysis conflicts with the assumption that pure tubulin dimer and monomer are in rapid equilibrium. This assumption underlies the many physical chemical measurements of the K d for dimer dissociation. To resolve this discrepancy we used surface plasmon resonance to determine the rate constant for dimer dissociation. The half-time for dissociation was ∼9.6 h with tubulin-GTP, 2.4 h with tubulin-GDP, and 1.3 h in the absence of nucleotide. AK d equal to 10−11 M was calculated from the measured rate for dissociation and an estimated rate for association. Dimer dissociation was found to be reversible, and dimer formation does not require GTP hydrolysis or folding information from protein cofactors, because 0.2 μM tubulin-GDP incubated for 20 h was eluted as dimer when analyzed by size exclusion chromatography. Because 20 h corresponds to eight half-times for dissociation, only monomer would be present if dissociation were an irreversible reaction and if dimer formation required GTP or protein cofactors. Additional evidence for a 10−11 M K d was obtained from gel exclusion chromatography studies of 0.02–2 nM tubulin-GDP. The slow dissociation of the tubulin dimer suggests that protein tubulin cofactors function to catalyze dimer dissociation, rather than dimer assembly. Assuming N-site-GTP dissociation is from monomer, our results agree with the 16-h half-time for N-site GTP in vitro and 33 h half-life for tubulin N-site-GTP in CHO cells.
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Hoyle, Henry D., F. Rudolf Turner, Linda Brunick, and Elizabeth C. Raff. "Tubulin Sorting during Dimerization In Vivo." Molecular Biology of the Cell 12, no. 7 (July 2001): 2185–94. http://dx.doi.org/10.1091/mbc.12.7.2185.

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We demonstrate sorting of β-tubulins during dimerization in theDrosophila male germ line. Different β-tubulin isoforms exhibit distinct affinities for α-tubulin during dimerization. Our data suggest that differences in dimerization properties are important in determining isoform-specific microtubule functions. The differential use of β-tubulin during dimerization reveals structural parameters of the tubulin heterodimer not discernible in the resolved three-dimensional structure. We show that the variable β-tubulin carboxyl terminus, a surface feature in the heterodimer and in microtubules, and which is disordered in the crystallographic structure, is of key importance in forming a stable α-β heterodimer. If the availability of α-tubulin is limiting, α-β dimers preferentially incorporate intact β-tubulins rather than a β-tubulin missing the carboxyl terminus (β2ΔC). When α-tubulin is not limiting, β2ΔC forms stable α-β heterodimers. Once dimers are formed, no further sorting occurs during microtubule assembly: α-β2ΔC dimers are incorporated into axonemes in proportion to their contribution to the total dimer pool. Co-incorporation of β2ΔC and wild-type β2-tubulin results in nonmotile axonemes because of a disruption of the periodicity of nontubulin axonemal elements. Our data show that the β-tubulin carboxyl terminus has two distinct roles: 1) forming the α-β heterodimer, important for all microtubules and 2) providing contacts for nontubulin components required for specific microtubule structures, such as axonemes.
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Maruta, H., K. Greer, and J. L. Rosenbaum. "The acetylation of alpha-tubulin and its relationship to the assembly and disassembly of microtubules." Journal of Cell Biology 103, no. 2 (August 1, 1986): 571–79. http://dx.doi.org/10.1083/jcb.103.2.571.

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A tight association between Chlamydomonas alpha-tubulin acetyltransferase (TAT) and flagellar axonemes, and the cytoplasmic localization of both tubulin deacetylase (TDA) and an inhibitor of tubulin acetylation have been demonstrated by the use of calf brain tubulin as substrate for these enzymes. A major axonemal TAT of 130 kD has been solubilized by high salt treatment, purified, and characterized. Using the Chlamydomonas TAT with brain tubulin as substrate, we have studied the effects of acetylation on the assembly and disassembly of microtubules in vitro. We also determined the relative rates of acetylation of tubulin dimers and polymers. The acetylation does not significantly affect the temperature-dependent polymerization or depolymerization of tubulin in vitro. Furthermore, polymerization of tubulin is not a prerequisite for the acetylation, although the polymer is a better substrate for TAT than the dimer. The acetylation is sensitive to calcium ions which completely inhibit the acetylation of both dimers and polymers of tubulin. Acetylation of the dimer is not inhibited by colchicine; the effect of colchicine on acetylation of the polymer can be explained by its depolymerizing effect on the polymer.
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Anders, Kirk R., and David Botstein. "Dominant-Lethal α-Tubulin Mutants Defective in Microtubule Depolymerization in Yeast." Molecular Biology of the Cell 12, no. 12 (December 2001): 3973–86. http://dx.doi.org/10.1091/mbc.12.12.3973.

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The dynamic instability of microtubules has long been understood to depend on the hydrolysis of GTP bound to β-tubulin, an event stimulated by polymerization and necessary for depolymerization. Crystallographic studies of tubulin show that GTP is bound by β-tubulin at the longitudinal dimer-dimer interface and contacts particular α-tubulin residues in the next dimer along the protofilament. This structural arrangement suggests that these contacts could account for assembly-stimulated GTP hydrolysis. As a test of this hypothesis, we examined, in yeast cells, the effect of mutating the α-tubulin residues predicted, on structural grounds, to be involved in GTPase activation. Mutation of these residues to alanine (i.e., D252A and E255A) created poisonous α-tubulins that caused lethality even as minor components of the α-tubulin pool. When the mutant α-tubulins were expressed from the galactose-inducible promoter ofGAL1, cells rapidly acquired aberrant microtubule structures. Cytoplasmic microtubules were largely bundled, spindle assembly was inhibited, preexisting spindles failed to completely elongate, and occasional, stable microtubules were observed unattached to spindle pole bodies. Time-lapse microscopy showed that microtubule dynamics had ceased. Microtubules containing the mutant proteins did not depolymerize, even in the presence of nocodazole. These data support the view that α-tubulin is a GTPase-activating protein that acts, during microtubule polymerization, to stimulate GTP hydrolysis in β-tubulin and thereby account for the dynamic instability of microtubules.
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Montecinos-Franjola, Felipe, Peter Schuck, and Dan L. Sackett. "Tubulin Dimer Reversible Dissociation." Journal of Biological Chemistry 291, no. 17 (March 2, 2016): 9281–94. http://dx.doi.org/10.1074/jbc.m115.699728.

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Liu, Ning, Ramana Pidaparti, and Xianqiao Wang. "Effect of amino acid mutations on intra-dimer tubulin–tubulin binding strength of microtubules." Integrative Biology 9, no. 12 (2017): 925–33. http://dx.doi.org/10.1039/c7ib00113d.

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Binding strength inside αβ-tubulin dimers of a microtubule (MT) with atomic resolutions are of importance in determining the structural stability of the MT as well as designing self-assembled functional structures from it. Through simulations, this study proposes a new strategy to tune the binding strength inside microtubules through point mutations of amino acids on the intra-dimer interface.
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Prota, Andrea E., Maria M. Magiera, Marijn Kuijpers, Katja Bargsten, Daniel Frey, Mara Wieser, Rolf Jaussi, et al. "Structural basis of tubulin tyrosination by tubulin tyrosine ligase." Journal of Cell Biology 200, no. 3 (January 28, 2013): 259–70. http://dx.doi.org/10.1083/jcb.201211017.

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Tubulin tyrosine ligase (TTL) catalyzes the post-translational retyrosination of detyrosinated α-tubulin. Despite the indispensable role of TTL in cell and organism development, its molecular mechanism of action is poorly understood. By solving crystal structures of TTL in complex with tubulin, we here demonstrate that TTL binds to the α and β subunits of tubulin and recognizes the curved conformation of the dimer. Biochemical and cellular assays revealed that specific tubulin dimer recognition controls the activity of the enzyme, and as a consequence, neuronal development. The TTL–tubulin structure further illustrates how the enzyme binds the functionally crucial C-terminal tail sequence of α-tubulin and how this interaction catalyzes the tyrosination reaction. It also reveals how TTL discriminates between α- and β-tubulin, and between different post-translationally modified forms of α-tubulin. Together, our data suggest that TTL has specifically evolved to recognize and modify tubulin, thus highlighting a fundamental role of the evolutionary conserved tubulin tyrosination cycle in regulating the microtubule cytoskeleton.
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Sackett, D. L., and J. Wolff. "Proteolysis of tubulin and the substructure of the tubulin dimer." Journal of Biological Chemistry 261, no. 19 (July 1986): 9070–76. http://dx.doi.org/10.1016/s0021-9258(19)84489-7.

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Serrano, L., and J. Avila. "The interaction between subunits in the tubulin dimer." Biochemical Journal 230, no. 2 (September 1, 1985): 551–56. http://dx.doi.org/10.1042/bj2300551.

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Limited proteolysis and chemical cross-linking techniques have been used to study the interaction between α- and β-tubulin subunits. Trypsin digestion of tubulin dimer resulted in the cleavage of the α-subunit into two fragments, whereas chymotrypsin cleaved the β-subunit into two distinct fragments. All of these fragments have been mapped on the tubulin subunits by further proteolysis with formic acid. Cross-linking of trypsin- and chymotrypsin-cleaved subunits has been performed with two different cross-linker agents of different cross-linking distance. The addition of formaldehyde resulted in the cross-linking of the α-tubulin N-terminal fragment with β-tubulin C-terminal domain. The same result was obtained when methyl 4-mercaptobutyrimidate was used.
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Dissertations / Theses on the topic "Tubulin dimer"

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BONANOMI, MARCELLA. "Normal and pathogenic ataxin-3: biological roles, toxicity and fibrillogenesis." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2014. http://hdl.handle.net/10281/50225.

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Ataxin-3 (AT3) is a deubiquitinating enzyme that triggers the inherited neurodegenerative disorder spinocerebellar ataxia type 3 when its polyglutamine (polyQ) stretch close to the C-terminus exceeds a critical length. It consists of the N-terminal globular Josephin domain (JD) and the C-terminal disordered one. Regarding its physiological role, it has ubiquitin hydrolase activity implicated in the function of the ubiquitin-proteasome system, but also plays a role in the pathway that sorts aggregated protein to aggresomes via microtubules. In the first part of this work, we further investigated its function(s) by taking advantage of Small Angle X-ray Scattering (SAXS) and Surface Plasmon Resonance (SPR). We demonstrated that an AT3 oligomer consisting of 6-7 subunits tightly binds to the tubulin hexameric oligomer at the level of three distinct tubulin-binding regions, one located in the JD, and the two others in the disordered domain, upstream and downstream of the polyQ stretch. By SPR we have also provided the first evidence of direct binding of AT3 to HDAC6, one of the components of the transport machinery that sorts protein to the aggresome. In the second part of this work, we have investigated the mechanisms of AT3 cytotoxicity triggered by expanded variants. For this purpose, we used Saccharomyces cerevisiae as a eukaryotic cellular model. We expressed a wild type (Q26), a pathogenic (Q85) and a truncated (291Δ) variant of the protein. The expanded form caused reduction in viability, accumulation of reactive oxygen species, imbalance of the antioxidant defense system and loss in cell membrane integrity. An AT3 variant truncated upstream of the polyQ also exerted a detrimental effect on cell growth and similar cytotoxicity, although to a lesser extent, which points to the involvement of also non-polyQ regions in cytotoxicity. Finally, we sought to evaluate the effects of tetracycline and epigallocatechin-3-gallate (EGCG), two well-known inhibitors of amyloid aggregation, on AT3 fibrillogenesis and cytotoxicity. We observed that tetracycline does not apparently change the aggregation mode, as supported by Fourier Transform Infrared spectroscopy and Atomic Force Microscopy data, but slightly retards further aggregation of the earliest soluble oligomers. In contrast, EGCG apparently increases the aggregation rate but also leads to the formation of off-pathway, non-amyloid, final aggregates. Despite these different effects, co-incubation of the AT3 with either compounds resulted in significantly lower cytotoxicity during AT3 aggregation.
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Škultétyová, Ľubica. "Hydrolasy závislé na zinku: Studium struktury a funkce glutamátkarboxypeptidasy II a histondeacetylasy 6." Doctoral thesis, 2018. http://www.nusl.cz/ntk/nusl-379495.

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Zinc-binding proteins represent approximately one tenth of the proteome and a good portion of them are zinc-dependent hydrolases. This thesis focuses on biochemical and structural characterization of glutamate carboxypeptidase II (GCPII) and histone deacetylase 6 (HDAC6), two members of the zinc-dependent metallohydrolase superfamily. We describe here their interactions with natural substrates and inhibitors. GCPII is a homodimeric membrane protease catalyzing hydrolytic cleavage of glutamate from the neurotransmitter N-acetylaspartylglutamate (NAAG) and dietary folates in the central and peripheral nervous systems and small intestine, respectively. This enzyme is associated with several neurological disorders and also presents an ideal target for imaging and treatment of prostate cancer. GCPII inhibitors typically consist of a zinc-binding group (ZBG) linked to an S1' docking moiety (a glutamate moiety or its isostere). As such, these compounds are highly hydrophilic molecules therefore unable to cross the blood-brain barrier and this hampers targeting GCPII to the central nervous system. Different approaches are adopted to alter the S1' docking moiety of the existing inhibitors. As a part of this thesis, we present different strategies relying on replacement of the canonical P1' glutamate residue...
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Černohorská, Markéta. "Nové regulační mechanismy nukleace mikrotubulů." Doctoral thesis, 2016. http://www.nusl.cz/ntk/nusl-350103.

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MT nucleation from γ-tubulin complexes, located at centrosome, is an essential step in the formation of MT cytoskeleton. In mammalian cells, -tubulin is encoded by two genes. We functionally characterized two γ-tubulin proteins and have found that both are functionally equivalent. γ-Tubulin 2 is able to substitute for γ-tubulin 1 in MT nucleation. However, we revealed that unlike TUBG1, TUBG2 expression is downregulated in mouse preimplantation development. Mast cells represent effectors of the allergy reaction. Their activation by antigen induces number of cellular processes such as degranulation, proliferation and cytoskeleton rearrangements. The regulatory mechanisms of MT reorganization during mast cell activation are unknown. We identified new signaling proteins, GIT1 and PIX that interact with - tubulin. Depletion of GIT1 or PIX leads to changes in MT nucleation. GIT1 is phosphorylated on tyrosine and associates with γ-tubulin in a Ca2+ -dependent manner. Our data suggested a novel signaling pathway for MT rearrangement in mast cells where tyrosine kinase-activated GIT1 and βPIX work in concert with Ca2+ signaling to regulate MT nucleation. We tested the capability of GIT1 and PIX to influence -tubulin function in more cell types. We found out that GIT1/βPIX signaling proteins together...
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Book chapters on the topic "Tubulin dimer"

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Sackett, Dan L. "Structure and Function in the Tubulin Dimer and the Role of the Acidic Carboxyl Terminus." In Subcellular Biochemistry, 255–302. Boston, MA: Springer US, 1995. http://dx.doi.org/10.1007/978-1-4899-1727-0_9.

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Lalani, M., and D. Galbraith. "Underwater strengthening, modification and repair techniques With and without diver or ROV intervention." In Tubular Structures VI, 215–21. London: Routledge, 2021. http://dx.doi.org/10.1201/9780203735015-32.

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Pizzi, R., S. Fiorentini, G. Strini, and M. Pregnolato. "Exploring Structural and Dynamical Properties Microtubules by Means of Artificial Neural Networks." In Complexity Science, Living Systems, and Reflexing Interfaces, 78–91. IGI Global, 2013. http://dx.doi.org/10.4018/978-1-4666-2077-3.ch005.

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Microtubules (MTs) are cylindrical polymers of the tubulin dimer, are constituents of all eukaryotic cells cytoskeleton and are involved in key cellular functions and are claimed to be involved as sub-cellular information or quantum information communication systems. The authors evaluated some biophysical properties of MTs by means of specific physical measures of resonance and birefringence in presence of electromagnetic field, on the assumption that when tubulin and MTs show different biophysical behaviours, this should be due to their special structural properties. Actually, MTs are the closest biological equivalent to the well-known carbon nanotubes (CNTs), whose interesting biophysical and quantum properties are due to their peculiar microscopic structure. The experimental results highlighted a physical behaviour of MTs in comparison with tubulin. The dynamic simulation of MT and tubulin subjected to electromagnetic field was performed via MD tools. Their level of self-organization was evaluated using artificial neural networks, which resulted to be an effective method to gather the dynamical behaviour of cellular and non-cellular structures and to compare their physical properties.
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Conference papers on the topic "Tubulin dimer"

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Deriu, Marco A., Monica Soncini, Mario Orsi, Mishal Patel, Jonathan W. Essex, Franco M. Montevecchi, and Alberto Redaelli. "Elastic Network Normal Mode Analysis for Microtubule Mechanics." In ASME 2009 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2009. http://dx.doi.org/10.1115/sbc2009-206618.

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The cellular microtubules MTs are hollow cylinder-shaped biopolymers with inner and outer diameter of about 17 and 25 nm and length ranging from 1 to 10 μm. They are constituted by αβ-tubulins arranged in protofilaments with a head-to-tail motif [1]. The protofilaments bind together laterally along the MT’s long axis with a slight shift generating a spiral with a pitch of 2, 3 or 4 monomers’ length (Fig.1a). The building-block of the MT, the αβ-tubulin, is a hetero-dimer made of two globular monomers, α- and β-tubulin, each of them consisting of about 450 residues with high degree of sequence similarity from the primary to the tertiary structure level [1].
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Deriu, Marco A., Søren Enemark, Emiliano Votta, Franco M. Montevecchi, Alberto Redaelli, and Monica Soncini. "Bottom-Up Mesoscale Model of Microtubule." In ASME 2007 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2007. http://dx.doi.org/10.1115/sbc2007-176115.

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Microtubules (MTs) are fundamental structural elements in the cytoskeleton of all eukaryotic cells. The MTs are hollow cylinder-shaped biopolymers with inner and outer diameter of about 18 and 30 nm respectively and length ranging from 1 to 10 μm. They are constituted by αβ-tubulins arranged in protofilaments with head-to-tail motif. The protofilaments bind together laterally along the MT’s long axis with a slight shift generating a spiral with a pitch of 2, 3 or 4 monomers’ length [1]. The building-block of the MT, αβ-tubulin, is a hetero-dimer made of two globular monomers, α- and β-tubulin. α- and β-tubulin monomers consists of about 450 residues and shows a high degree of similarity from the primary to the tertiary structure level. However, one important difference is that the α-monomer binds a GTP molecule while the β-monomer binds a GDP molecule [2].
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Enemark, So̸ren, Marco A. Deriu, and Monica Soncini. "Mechanical Properties of Tubulin Molecules by Molecular Dynamics Simulations." In ASME 8th Biennial Conference on Engineering Systems Design and Analysis. ASMEDC, 2006. http://dx.doi.org/10.1115/esda2006-95674.

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The basic unit in microtubules is αβ-tubulin, a hetero-dimer consisting of an α- and a β-tubulin monomer. The mechanical characteristics of the dimer as well as of the individual monomers may be used to obtain new insight into the microtubule tensile properties. In the present work we evaluate the elastic constants of each of the monomers and the interaction force between them by means of molecular dynamics simulations. Molecular models of α-, β-, and αβ-tubulin were developed starting from the 1TUB.pdb structure from the RSCB database. Simulations were carried out in a solvated environment using explicit water molecules. In order to measure the monomers’ elastic constants, simulations were performed by mimicking experiments carried out with atomic force microscopy. A different approach was used to determine the interaction force between the α- and β-monomers using 8 different monomer configurations based on different inter-monomer distances. The obtained results show an elastic constant value for α-tubulin of 3.4–3.9 N/m, while for the β-tubulin the elastic constant was measured to be 1.8–2.4 N/m. The maximum interaction force between the monomers was estimated to be 11.2 nN. In perspective, these outcomes will allow exchanging atomic level description with key mechanical features enabling microtubule characterisation by continuum mechanics approach.
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McMicken, Brady, and Lorenzo Brancaleon. "Photoinduced unfolding of tubulin dimers bound to meso-tetrakis (sulfonatophenyl) porphyrin." In SPIE BiOS, edited by E. Duco Jansen and Robert J. Thomas. SPIE, 2011. http://dx.doi.org/10.1117/12.881730.

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Allen, Kathleen B., and Bradley E. Layton. "Mechanical Neural Growth Models." In ASME 2005 International Mechanical Engineering Congress and Exposition. ASMEDC, 2005. http://dx.doi.org/10.1115/imece2005-79445.

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Critical to being able to control the growth patterns of cell-based sensors is being able to understand how the cytoskeleton of the cell maintains its structure and integrity both under mechanical load and in a load-free environment. Our approach to a better understanding of cell growth is to use a computer simulation that incorporates the primary structures, microtubules, necessary for growth along with their observed behaviors and experimentally determined mechanical properties. Microtubules are the main compressive structural support elements for the axon of a neuron and are created via polymerization of α-β tubulin dimers. Our de novo simulation explores the mechanics of the forces between microtubules and the membrane. We hypothesize that axonal growth is most influenced by the location and direction of the force exerted by the microtubule on the membrane, and furthermore that the interplay of forces between microtubules and the inner surface of the cell membrane dictates the polar structure of axons. The simulation will be used to understand cytoskeletal mechanics for the purpose of engineering cells to be used as sensors.
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Zhang, Y. H., and A. Stacey. "Review and Assessment of Fatigue Data for Offshore Structural Components Containing Through-Thickness Cracks." In ASME 2008 27th International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2008. http://dx.doi.org/10.1115/omae2008-57503.

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In recent years, structural integrity management schemes for offshore installations have placed increased reliance on the use of flooded member detection (FMD) as the principal inspection method. This method can be routinely employed in a remotely operated vehicle, which enables a large number of members to be inspected fairly quickly at a much reduced cost compared to using diver operated techniques. However, reliance on FMD for safety assurance requires that welded joints retain sufficient fatigue life and static strength after through-thickness cracking. A comprehensive examination of published work containing data on fatigue lives beyond through-thickness cracking in offshore structures was carried out, resulting in the development of a database of 281 relevant tests. The database was used to perform a statistical assessment of the effects of different testing conditions and geometrical parameters on the remaining fatigue life beyond the occurrence of through-thickness cracking, N3, which was represented by a parameter Re. Whilst the data showed a large amount of scatter, it was found that Re depends strongly on chord thickness, loading mode, type of joint and testing environment. In some cases, a significant amount of remaining life existed. This was often associated with T-type tubular joints with thin chord thickness under out-of-plane loading and a seawater (with CP) environment. The influence of the relevant parameters on Re is discussed and attributed to their effect on crack shape, stress distribution, cracking location and crack propagation path.
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