scholarly journals Tubulin Lattice in Cilia is in a Stressed Form Regulated by Microtubule Inner Proteins

2019 ◽  
Author(s):  
Muneyoshi Ichikawa ◽  
Ahmad Abdelzaher Khalifa ◽  
Kaustuv Basu ◽  
Daniel Dai ◽  
Mohammad Amin Faghfor Maghrebi ◽  
...  
Keyword(s):  
Lattice Structure ◽  
Atomic Resolution ◽  
High Frequencies ◽  
Lateral Angle ◽  
A Cell ◽  
Longitudinal Compaction ◽  
Resolution Map

AbstractCilia, the hair-like protrusions that beat at high frequencies to propel a cell or move fluid around the cell, are composed of radially bundled doublet microtubules. The doublet microtubule is composed of a 13-protofilament A-tubule, a partial 10-protofilament B-tubule and microtubule inner proteins (MIPs) inside the tubulin lattice. In this study, we present the near-atomic resolution map of theTetrahymenadoublet microtubules. The map demonstrates that the network of microtubule inner proteins is weaving into the tubulin lattice, forming an inner sheath of proteins. In addition, we also obtain the tubulin lattice structure with missing MIPs by Sarkosyl treatment. In this structure, the tubulin lattice showed significant longitudinal compaction and lateral angle changes between protofilaments. These results are evidence that the binding of MIPs directly affects and stabilizes the tubulin lattice. It is also suggested that the doublet microtubule is an intrinsically stressed filament and this stress could be exploited in the regulation of ciliary waveforms.

scholarly journals Tubulin lattice in cilia is in a stressed form regulated by microtubule inner proteins

2019 ◽  
Vol 116 (40) ◽  
pp. 19930-19938 ◽  
Author(s):  
Muneyoshi Ichikawa ◽  
Ahmad Abdelzaher Zaki Khalifa ◽  
Shintaroh Kubo ◽  
Daniel Dai ◽  
Kaustuv Basu ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
De Novo ◽  
Lattice Structure ◽  
Mass Spectrometry Data ◽  
Atomic Resolution ◽  
High Frequencies ◽  
Tubulin Dimer ◽  
Angle Change ◽  
A Cell ◽  
Longitudinal Compaction

Cilia, the hair-like protrusions that beat at high frequencies to propel a cell or move fluid around are composed of radially bundled doublet microtubules. In this study, we present a near-atomic resolution map of the Tetrahymena doublet microtubule by cryoelectron microscopy. The map demonstrates that the network of microtubule inner proteins weaves into the tubulin lattice and forms an inner sheath. From mass spectrometry data and de novo modeling, we identified Rib43a proteins as the filamentous microtubule inner proteins in the protofilament ribbon region. The Rib43a–tubulin interaction leads to an elongated tubulin dimer distance every 2 dimers. In addition, the tubulin lattice structure with missing microtubule inner proteins (MIPs) by sarkosyl treatment shows significant longitudinal compaction and lateral angle change between protofilaments. These results are evidence that the MIPs directly affect and stabilize the tubulin lattice. It suggests that the doublet microtubule is an intrinsically stressed filament and that this stress could be manipulated in the regulation of ciliary waveforms.

scholarly journals 3P147 Approach to obtain near-atomic resolution map of actin-myosin rigor complex by cryo-EM(11. Molecular motor,Poster)

2013 ◽  
Vol 53 (supplement1-2) ◽  
pp. S236
Author(s):  
Norihiro Shimizu ◽  
Yoshihiro Tsukada ◽  
Takuo Yasunaga
Keyword(s):  
Molecular Motor ◽  
Atomic Resolution ◽  
Resolution Map

scholarly journals Crystallization and Preliminary X-Ray Analysis of Rotavirus Protein VP6

1998 ◽  
Vol 72 (9) ◽  
pp. 7615-7619 ◽  
Author(s):  
Isabelle Petitpas ◽  
Jean Lepault ◽  
Patrice Vachette ◽  
Annie Charpilienne ◽  
Magali Mathieu ◽  
...  
Keyword(s):  
Atomic Resolution ◽  
Asymmetric Unit ◽  
Tubular Structures ◽  
Solvent Content ◽  
X Ray ◽  
X Ray Scattering ◽  
A Cell ◽  
Crystallization Conditions ◽  
Insight Into ◽  
Better Than

ABSTRACT As a first step to gain insight into the structure of the rotavirus virion at atomic resolution, we report here the expression, purification, and crystallization of recombinant rotavirus protein VP6. This protein has the property of polymerizing in the form of tubular structures in solution which have hindered crystallization thus far. Using a combination of electron microscopy and small-angle X-ray scattering, we found that addition of Ca2+ at concentrations higher than 100 mM results in depolymerization of the tubes, leading to an essentially monodisperse solution of trimeric VP6 even at high protein concentrations (higher than 10 mg/ml), thereby enabling us to search for crystallization conditions. We have thus obtained crystals of VP6 which diffract to better than 2.4 Å resolution and belong to the cubic space group P4132 with a cell dimension a of 160 Å. The crystals contain a trimer of VP6 lying along the diagonal of the cubic unit cell, resulting in one VP6 monomer per asymmetric unit and a solvent content of roughly 70%.

scholarly journals Cell Culture on Low-Fluorescence and High-Resolution Photoresist

Micromachines ◽  
2020 ◽  
Vol 11 (6) ◽  
pp. 571
Author(s):  
Hidetaka Ueno ◽  
Katsuya Maruo ◽  
Masatoshi Inoue ◽  
Hidetoshi Kotera ◽  
Takaaki Suzuki
Keyword(s):  
Cell Culture ◽  
Hela Cells ◽  
Lattice Structure ◽  
Plastic Substrate ◽  
Cell Analysis ◽  
Surface Conditions ◽  
Wide Range ◽  
A Cell ◽  
Adhesion Rate ◽  
Auto Fluorescence

2D and 3D topographic cues made of photoresist, a polymer, are used for cell culture and cell analysis. Photoresists used for cell analysis provide the surface conditions necessary for proper cell growth, along with patterning properties of a wide range and high precision, and low auto-fluorescence that does not affect fluorescence imaging. In this study, we developed a thick negative photoresist SJI-001 possessing the aforementioned properties. We evaluated the surface conditions of SJI-001 affecting cell culture. First, we studied the wettability of SJI-001, which was changed by plasma treatment, conducted as a pretreatment on a plastic substrate before cell seeding. SJI-001 was more chemically stable than SU-8 used for fabricating the micro-electromechanical systems (MEMS). Furthermore, the doubling time and adhesion rate of adherent HeLa cells cultured on untreated SJI-001 were 25.2 h and 74%, respectively, thus indicating its suitability for cell culture over SU-8. In addition, we fabricated a cell culture plate with a 3D lattice structure, three micrometers in size, using SJI-001. HeLa cells seeded on this plate remained attached over five days. Therefore, SJI-001 exhibits surface conditions suitable for cell culture and has several bioapplications including microstructures and cell chips for cell culture and cell analysis.

scholarly journals Maintenance of neuronal size gradient in MNTB requires sound-evoked activity

2017 ◽  
Vol 117 (2) ◽  
pp. 756-766 ◽  
Author(s):  
Jessica H. Weatherstone ◽  
Conny Kopp-Scheinpflug ◽  
Nadia Pilati ◽  
Yuan Wang ◽  
Ian D. Forsythe ◽  
...  
Keyword(s):  
Cell Size ◽  
Calcium Atpase ◽  
Plasma Membrane Calcium Atpase ◽  
High Frequencies ◽  
Medial Nucleus ◽  
Soma Size ◽  
A Cell ◽  
Evoked Activity ◽  
Size Gradient ◽  
Trapezoid Body

The medial nucleus of the trapezoid body (MNTB) is an important source of inhibition during the computation of sound location. It transmits fast and precisely timed action potentials at high frequencies; this requires an efficient calcium clearance mechanism, in which plasma membrane calcium ATPase 2 (PMCA2) is a key component. Deafwaddler ( dfw 2J) mutant mice have a null mutation in PMCA2 causing deafness in homozygotes ( dfw 2J/ dfw 2J) and high-frequency hearing loss in heterozygotes (+/ dfw 2J). Despite the deafness phenotype, no significant differences in MNTB volume or cell number were observed in dfw 2J homozygous mutants, suggesting that PMCA2 is not required for MNTB neuron survival. The MNTB tonotopic axis encodes high to low sound frequencies across the medial to lateral dimension. We discovered a cell size gradient along this axis: lateral neuronal somata are significantly larger than medially located somata. This size gradient is decreased in +/ dfw 2J and absent in dfw 2J/ dfw 2J. The lack of acoustically driven input suggests that sound-evoked activity is required for maintenance of the cell size gradient. This hypothesis was corroborated by selective elimination of auditory hair cell activity with either hair cell elimination in Pou4f3 DTR mice or inner ear tetrodotoxin (TTX) treatment. The change in soma size was reversible and recovered within 7 days of TTX treatment, suggesting that regulation of the gradient is dependent on synaptic activity and that these changes are plastic rather than permanent. NEW & NOTEWORTHY Neurons of the medial nucleus of the trapezoid body (MNTB) act as fast-spiking inhibitory interneurons within the auditory brain stem. The MNTB is topographically organized, with low sound frequencies encoded laterally and high frequencies medially. We discovered a cell size gradient along this axis: lateral neurons are larger than medial neurons. The absence of this gradient in deaf mice lacking plasma membrane calcium ATPase 2 suggests an activity-dependent, calcium-mediated mechanism that controls neuronal soma size.

scholarly journals Atomic resolution map of the soluble amyloid beta assembly toxic surfaces

2019 ◽  
Vol 10 (24) ◽  
pp. 6072-6082 ◽  
Author(s):  
Rashik Ahmed ◽  
Michael Akcan ◽  
Adree Khondker ◽  
Maikel C. Rheinstädter ◽  
José C. Bozelli ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Amyloid Beta ◽  
Atomic Resolution ◽  
Resolution Map

Atomic resolution map of the soluble amyloid beta assembly (Aβn) “toxic surfaces” that facilitate the early pathogenic events in Alzheimer's disease (AD).

scholarly journals Combined Spectrophotometric— Electrochemical Impedance Imaging System for Biofilm Research

2005 ◽  
Vol 10 (1) ◽  
pp. 16-23 ◽  
Author(s):  
Chirag Patel ◽  
Stanley Dunn ◽  
Paul Takhistov
Keyword(s):  
Electrochemical Impedance ◽  
Imaging System ◽  
Impedance Analysis ◽  
Low Frequencies ◽  
High Frequencies ◽  
Impedance Imaging ◽  
Noninvasive Analysis ◽  
A Cell ◽  
Computer Controlled ◽  
Automatic Scanning

We propose an automatic scanning microscope that is capable of analyzing the properties of the biofilm-associated cells by using optical and impedance spectroscopy. The operating principle of the instrument is based on measuring the electrical impedance of cell culture grown on a conductive substratum that is used as one of the electrodes. At low frequencies, the impedance analysis is capable of characterizing a biofilm at the macroscale, and at high frequencies it is capable of analyzing the peculiarities of a cell layer at the level of single microorganisms. The combination of these two techniques is sufficient to give a quantitative and structural composition of a biofilm at both levels. The developed instrument can be useful in the broad range of biofilmrelated research studies, providing the data for detailed, real-time, computer-controlled, noninvasive analysis of cell-to-cell and cell-to-surface interactions.

Atomic Resolution Map of Hierarchical Self-Assembly for an Amyloidogenic Protein Probed through Thermal 15N–R2 Correlation Matrices

2021 ◽  
Vol 143 (12) ◽  
pp. 4668-4679
Author(s):  
Rashik Ahmed ◽  
Jinfeng Huang ◽  
Madoka Akimoto ◽  
Tongyu Shi ◽  
Giuseppe Melacini
Keyword(s):  
Self Assembly ◽  
Atomic Resolution ◽  
Correlation Matrices ◽  
Amyloidogenic Protein ◽  
Resolution Map

The Effects of Vibrations on Particle Motion Near a Wall in a Semi-Infinite Fluid Cell

2005 ◽  
Vol 73 (4) ◽  
pp. 610-621 ◽  
Author(s):  
Samer Hassan ◽  
Masahiro Kawaji ◽  
Tatyana P. Lyubimova ◽  
Dmitry V. Lyubimov
Keyword(s):  
Cell Wall ◽  
Resonance Frequency ◽  
Particle Motion ◽  
Equilibrium Position ◽  
Inviscid Fluid ◽  
High Frequencies ◽  
Theoretical Predictions ◽  
A Cell ◽  
Wall Proximity ◽  
Fluid Cell

The effects of small vibrations on a particle-fluid system relevant to material processing such as crystal growth in space have been investigated experimentally and theoretically. An inviscid model for a spherical particle of radius, R0, suspended by a thin wire and moving normal to a cell wall in a semi-infinite liquid-filled cell subjected to external horizontal vibrations, was developed to predict the vibration-induced particle motion under normal gravity. The wall effects were studied by varying the distance between the equilibrium position of the particle and the nearest cell wall, H. The method of images was used to derive the equation of motion for the particle oscillating in an inviscid fluid normal to the nearest cell wall. The particle amplitude in a semi-infinite cell increased linearly with the cell vibration amplitude as expected from the results for an infinite cell, however, the particle amplitude also changed with the distance between the equilibrium position of the particle and the nearest wall. The particle amplitude was also found to increase or decrease depending on whether the cell vibration frequency was below or above the resonance frequency, respectively. The theoretical predictions of the particle amplitudes in the semi-infinite cell agreed well with the experimental data, where the effect of the wall proximity on the particle amplitude was found to be significant for (H∕R0<2) especially near the resonance frequency. Experiments performed at high frequencies well above the resonance frequency showed that the particle amplitude reaches an asymptotic value independent of the wire length.

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