• filaments
  • Microtubules can also morph into other forms such as helical filaments, which are observed in protist organisms like foraminifera. (wikipedia.org)
  • Usually, it is the C-terminal domain of the MAP that interacts with tubulin, while the N-terminal domain can bind with cellular vesicles, intermediate filaments or other microtubules. (wikipedia.org)
  • In earlier work, Frey's group had shown that the density of molecular motors attached to the filaments has an impact on whether the microtubule grows or shrinks, and that their effect depends on the length of the filament concerned. (uni-muenchen.de)
  • Microtubules are one of three cytoskeletal filaments found in eukaryotic cells, which exhibit a constant transition between growth and shrinkage states. (foresight.org)
  • In conclusion, by analyzing the experimental data for pure isotype microtubules we were able to determine varying nanoscale mechanical properties of these filaments such as force generation and rigidity. (foresight.org)
  • Kinesins move along microtubule (MT) filaments, and are powered by the hydrolysis of adenosine triphosphate (ATP) (thus kinesins are ATPases). (wikipedia.org)
  • The common methods in nanobiomechanics are summarized below: Atomic force microscope Optical tweezers Magnetic twisting cytometry bone and its hierarchical constituents such as single collagen fibrils single living cells actin filaments and microtubules synthetic peptide nanotubes In addition to experimental aspect, research has been expanding through computational methods. (wikipedia.org)
  • protofilaments
  • Microtubules were modeled as anisotropic, with the Young's modulus corresponding to the resistance of protofilaments to stretching and the shear modulus describing the weak interaction between the protofilaments. (epfl.ch)
  • Bending measurements performed on microtubules deposited on lithographically fabricated substrates show that this temperature dependence is due to changing shear modulus, implying that the lateral interaction between the protofilaments is strongly determined by the temperature. (epfl.ch)
  • cytoplasmic microtubules
  • Building on the earlier work by Sinnott and Bloch, who had shown that wounding the existing tracheary elements in a Coleus stem induced neighboring parenchyma cells to differentiate into new tracheary elements, Hepler showed that cytoplasmic microtubules were localized specifically in the cortical cytoplasm immediately over the bands of new secondary wall thickenings. (wikipedia.org)
  • depolymerization
  • This cap provides both stability and protection to the microtubule (-) end from enzymes that could lead to its depolymerization, while also inhibiting (-) end growth. (wikipedia.org)
  • This is partly due to phosphorylation of XMAP215, which makes catastrophes (rapid depolymerization of microtubules) more likely. (wikipedia.org)
  • Experiments performed at about the same time showed that treatment of A. nucleofilum cells with agents that cause microtubule depolymerization-mainly, hydrostatic pressure and colchicine treatment-gave similar results (Tilney et al. (rupress.org)
  • In this paper we analyze the differences between the polymerization and depolymerization rates of purified β-II, β-III, and β-IV microtubules. (foresight.org)
  • Microtubules (MTs) are dynamic polar polymers assembled from tubulin heterodimers and alternating polymerization and depolymerization phases at their ends . (plos.org)
  • regulate
  • Together with Guoqiang Gu, Ph.D., associate professor of Cell and Developmental Biology, and other Vanderbilt laboratories, the investigators demonstrated using multiple systems and technologies that microtubules negatively regulate insulin secretion in beta cells. (eurekalert.org)
  • The insulin granules 'walk' randomly on the microtubule mesh, and the microtubules regulate the number of granules at the cell periphery to prevent over-secretion," Kaverina said. (eurekalert.org)
  • cellular
  • Microtubules are very important in a number of cellular processes. (wikipedia.org)
  • Microtubules can spontaneously self-organize, transforming from many singular components into one large cellular structure capable of performing specific tasks. (eurekalert.org)
  • Microtubules are at the heart of cellular self-organization, and their dynamic nature allows them to explore the intracellular space and mediate the transport of cargoes from the nucleus to the outer edges of the cell and back. (springer.com)
  • Microtubules -- cellular "highways" that deliver cargo to the cell membrane for secretion -- have a surprising role in pancreatic beta cells. (eurekalert.org)
  • The findings reveal that microtubules act as a cellular "rheostat" to precisely control insulin secretion and suggest that disturbance of this control may contribute to beta cell dysfunction and type 2 diabetes. (eurekalert.org)
  • stability
  • Thus, the hyperphosphorylation of tau leads to massive detachment, which in turn greatly reduces the stability of microtubules in nerve cells. (wikipedia.org)
  • Microtubules not only confer mechanical stability on cells and help to dictate their form, they also serve as an intracellular transport network. (uni-muenchen.de)
  • cortical
  • Spinning disk confocal microscopy revealed that CESA complexes in the plasma membrane moved at constant rates in linear tracks that were aligned and were coincident with cortical microtubules. (sciencemag.org)
  • He received his B.S. in chemistry from the University of New Hampshire in 1958 and earned his Ph.D. in plant cell biology from University of Wisconsin in 1964, studying the role of cortical microtubules in plant cell development with Eldon H. Newcomb. (wikipedia.org)
  • cilia
  • Microtubules are nucleated and organized by microtubule organizing centers (MTOCs), such as the centrosome found in the center of many animal cells or the basal bodies found in cilia and flagella, or the spindle pole bodies found in most fungi. (wikipedia.org)
  • In epithelial cells, MTOCs also anchor and organize the microtubules that make up cilia. (wikipedia.org)
  • The axoneme of primary cilia typically has a ring of nine outer microtubule doublets (called a 9+0 axoneme), and the axoneme of a motile cilium has two central microtubule singlets in addition to the nine outer doublets (called a 9+2 axoneme). (wikipedia.org)
  • MAP2
  • A single study has suggested that MAP2 and tau bind on the inner microtubule surface on the same site in tubulin monomers as the drug Taxol, which is used in treating cancer, but this study has not been confirmed. (wikipedia.org)
  • Like MAP2 and tau, MAP4 is responsible for stabilization of microtubules. (wikipedia.org)
  • MTOCs
  • Some cells however, such as those of higher plants and oocytes, lack distinct MTOCs and microtubules are nucleated via a non-centrosomal pathway. (wikipedia.org)
  • Other cells, such as neurons, skeletal muscle cells, and epithelial cells, which do have MTOCs, possess arrays of microtubules not associated with a centrosome. (wikipedia.org)
  • mitotic spindle
  • Furthermore, microtubules are the major constituents of the mitotic spindle, which mediates the orderly segregation of the replicated chromosome sets into the two daughter cells during cell division. (uni-muenchen.de)
  • Earlier work by Inoué (1952) had shown that when cells are exposed to cold temperatures the mitotic spindle-later shown to be composed of microtubules-disappears. (rupress.org)
  • axoneme
  • Undulipodia are an extension of the cell membrane containing both cytoplasm and a regular arrangement of microtubules known as an axoneme. (wikipedia.org)
  • geometries
  • These non-centrosomal microtubule arrays can take on various geometries-such as those lead to the long, slender shape of myotubes, the fine protrusions of an axon, or the strongly polarized domains of an epithelial cell. (wikipedia.org)
  • Microtubules deposited on prefabricated substrates were deformed in an atomic force microscope during imaging, in two different experimental geometries. (epfl.ch)
  • MTOC
  • The γ-TuRC is typically found as the core functional unit in a microtubule organizing center (MTOC), such as the centrosome in animal cells or the spindle pole bodies in fungi and algae. (wikipedia.org)
  • Microtubules are anchored at the MTOC by their minus ends, while their plus ends continue to grow into the cell periphery. (wikipedia.org)
  • binds
  • meaning, the heads only binds to the microtubule in one orientation, while ATP binding gives each step its direction through a process known as neck linker zippering. (wikipedia.org)
  • novel
  • A better understanding of how microtubule dynamic instability is regulated could open new opportunities for improving the potency and selectivity of existing anti-cancer drugs, as well as facilitate the development of novel agents," Nogales says. (lbl.gov)
  • Self organization of the kinesin-microtubule system was implemented as a novel template to create percolated nanofiber networks. (springer.com)
  • organize
  • Very quickly, we saw that these microtubules organize into networks that spontaneously contract," Foster said. (eurekalert.org)
  • In this work, the use of self-organized microtubule architectures as a template to organize nanomaterials was demonstrated using cellulose nanowhiskers. (springer.com)
  • The decentralized microtubule arrays appear to self-organize, but this is coordinated by plus- and minus-end-directed kinesin motors. (biologists.org)
  • growth
  • The γ-TuRC also acts as a cap of the (−) end while the microtubule continues growth from its (+) end. (wikipedia.org)
  • There is also, a class of the +TIPs which substantiates a TOG domain, arranged properly these domains allow mediation of binding to tubulin and are important for microtubule growth correlated activity. (wikipedia.org)
  • At the end, motor-dependent shrinkage thus competes with microtubule growth. (uni-muenchen.de)
  • The authors concluded that "microtubules are intimately involved not only with the maintenance of the axopodia but also with their growth. (rupress.org)
  • We developed a model that describes the different growth and shrinkage behavior of each isotype in terms of a recursive map representation based on a modified random walk with four independent probabilistic variables describing the possible states of a microtubule. (foresight.org)
  • Using further probabilistic methods, we simulated the growth and shrinkage behavior of isotypically pure microtubules and determined their average growth and shrinkage rate constants and their probability distributions. (foresight.org)
  • This variation in growth and shrinkage rates subsequently leads to a variation in the forces generated by isotypically purified microtubules that were calculated from a force-velocity relationship. (foresight.org)
  • It has also been suggested that microtubule rigidity is directly related to the rate of growth, and that slower growing microtubules are stiffer. (foresight.org)
  • Here again, the β-tubulin isotype composition can be varied in order to produce a microtubule with a specific growth rate, in order to produce a microtubule of desired rigidity. (foresight.org)
  • Stoppin-Mellet V, Fache V, Portran D, Martiel J-L, Vantard M (2013) MAP65 Coordinate Microtubule Growth during Bundle Formation. (plos.org)
  • anticancer drugs
  • Beyond their importance to our understanding of basic cell biology, microtubules are a major target for anticancer drugs, such as Taxol, which can prevent the transition from growing to shrinking nucleotide states or vice versa. (lbl.gov)
  • mammalian
  • The new results show that the extra load is lightened in mammalian cells at late anaphase, when microtubules were released both individually and in clusters. (rupress.org)
  • The addition of the DAD to mammalian cells induces actin filament formation, stabilises microtubules, and activates serum-response mediated transcription. (wikipedia.org)
  • structures
  • Particularly for the Golgi apparatus, structures associated with the apparatus travel towards the minus end of a microtubule and aid in the overall structure and site of the Golgi in the cell. (wikipedia.org)
  • Gregory Alushin and Eva Nogales studying images of microtubule structures. (lbl.gov)
  • Microtubules (MTs) are highly dynamical structures that play a crucial role in cell physiology. (plos.org)
  • dynamic
  • These dyneins have their light chains (static portion) attached to the cell membrane, and their globular parts (dynamic portions) attached to the microtubules. (wikipedia.org)
  • In this fashion dynamic arrays of microtubules can be generated without the aid of the γ-TuRC. (wikipedia.org)
  • Because the freed microtubules are not protected at their minus ends, they are more dynamic and turn over more rapidly than attached microtubules. (rupress.org)
  • The dynamic instability that makes it possible for microtubules to transition from a rigid polymerized or "assembled" nucleotide state to a flexible depolymerized or "disassembled" nucleotide state is driven by guanosine triphosphate (GTP) hydrolysis in the microtubule lattice. (lbl.gov)
  • The findings suggest that in response to the increased demand for insulin in diabetes, microtubules become more dense and less dynamic as a feedback mechanism, ultimately shutting down beta cell function, Gu said. (eurekalert.org)
  • This enables us to extrapolate these results to a model that can predict the dynamic instability of microtubules with an arbitrary isotype composition. (foresight.org)