Read by QxMD icon Read


Eleni Fegaras, Arthur Forer
In a typical cell division, chromosomes align at the metaphase plate before anaphase commences. This is not the case in Mesostoma spermatocytes. Throughout prometaphase, the three bivalents persistently oscillate towards and away from either pole, at average speeds of 5-6 μm/min, without ever aligning at a metaphase plate. In our experiments, nocodazole (NOC) was added to prometaphase spermatocytes to depolymerize the microtubules. Traditional theories state that microtubules are the producers of force in the spindle, either by tubulin depolymerizing at the kinetochore (PacMan) or at the pole (Flux)...
February 21, 2018: Protoplasma
Yuka Yamagishi, Kazumasa Oya, Akira Matsuura, Hiroshi Abe
Two types of Arp2/3 complex inhibitors, CK-666/636 and CK-548/869, are commonly used to study Arp2/3 complex-dependent actin assembly both in vitro and in vivo. However, we found that CK-548 and CK-869 directly suppress microtubule (MT) assembly independent of the actin cytoskeleton. Treatment of cultured mammalian cells with 50 μM CK-869 dramatically decreased MT networks and, instead, accumulated tubulin at the cell periphery, as did nocodazole that inhibits MT assembly. An in vitro MT-sedimentation assay revealed that CK-548 and CK-869 significantly suppressed MT polymerization...
January 27, 2018: Biochemical and Biophysical Research Communications
Jing Shen, Jiang-Hui Zhang, Han Xiao, Ji-Min Wu, Kang-Min He, Zhi-Zhen Lv, Zi-Jian Li, Ming Xu, You-Yi Zhang
Membrane nanotubes (MNTs) act as "highways" between cells to facilitate the transfer of multiple signals and play an important role in many diseases. Our previous work reported on the transfer of mitochondria via MNTs between cardiomyocytes (CMs) and cardiac myofibroblasts (MFs); however, the elucidation of the underlying mechanism and pathophysiological significance of this transfer requires additional study. In this study, we determined that the mean movement velocity of mitochondria in MNTs between CMs and MFs was approximately 17...
January 23, 2018: Cell Death & Disease
Eleni Petsalaki, Maria Dandoulaki, George Zachos
The mitotic spindle checkpoint delays anaphase onset in the presence of unattached kinetochores, and efficient checkpoint signaling requires kinetochore localization of the Rod-ZW10-Zwilch (RZZ) complex. In the present study, we show that human Chmp4c, a protein involved in membrane remodeling, localizes to kinetochores in prometaphase but is reduced in chromosomes aligned at the metaphase plate. Chmp4c promotes stable kinetochore-microtubule attachments and is required for proper mitotic progression, faithful chromosome alignment, and segregation...
January 23, 2018: Journal of Cell Biology
Yajuan Lu, Sen Li, Zhaokang Cui, Xiaoxin Dai, Mianqun Zhang, Yilong Miao, Changyin Zhou, Xianghong Ou, Bo Xiong
Esco1 has been reported to function as a cohesion establishment factor that mediates chromosome cohesion and segregation in mitotic cells. However, its exact roles in meiosis have not been clearly defined. Here, we document that Esco1 is expressed and localized to both the nucleus and cytoplasm during mouse oocyte meiotic maturation. Depletion of Esco1 by siRNA microinjection causes the meiotic progression arrest with a severe spindle abnormality and chromosome misalignment, which is coupled with a higher incidence of the erroneous kinetochore-microtubule attachments and activation of spindle assembly checkpoint...
January 19, 2018: Nucleic Acids Research
Yang Yang, Xuan Zhang, Hongfei Ge, Wei Liu, Eryi Sun, Yuanyuan Ma, Hengli Zhao, Rongwei Li, Weixiang Chen, Jichao Yuan, Qianwei Chen, Yujie Chen, Xin Liu, John H Zhang, Rong Hu, Xiaotang Fan, Hua Feng
BACKGROUND: Many previous clinical studies have demonstrated that the nigrostriatal pathway, which plays a vital role in movement adjustment, is significantly impaired after stroke, according to medical imaging and autopsies. However, the basic pathomorphological changes have been poorly investigated to date. This study was designed to explore the pathomorphological changes, mechanism, and therapeutic method of nigrostriatal impairment after intracerebral hemorrhage (ICH). METHODS AND RESULTS: Intrastriatal injection of autologous blood or microtubule depolymerization reagent nocodazole was performed to mimic the pathology of ICH in C57/BL6 mice...
January 18, 2018: Journal of the American Heart Association
David S Moura, Ignacio Campillo-Marcos, Marta Vázquez-Cedeira, Pedro A Lazo
Regulation of cell division requires the integration of signals implicated in chromatin reorganization and coordination of its sequential changes in mitosis. Vaccinia-related kinase 1 (VRK1) and Aurora B (AURKB) are two nuclear kinases involved in different steps of cell division. We have studied whether there is any functional connection between these two nuclear kinases, which phosphorylate histone H3 in Thr3 and Ser10, respectively. VRK1 and AURKB are able to form a stable protein complex, which represents only a minor subpopulation of each kinase within the cell and is detected following nocodazole release...
January 16, 2018: Cellular and Molecular Life Sciences: CMLS
Yinghui Mao
Accurate sister chromatid segregation is pivotal in the faithful transmission of genetic information during each cell division. To ensure accurate segregation, eukaryotic organisms have evolved a "mitotic (or spindle assembly) checkpoint" to prevent premature advance to anaphase before successful attachment of every chromosome to the microtubules of the mitotic spindle. An unattached kinetochore generates a diffusible signal that inhibits ubiquitination of substrates such as cyclin B and securins. This protocol presents an in vitro assay for studying the mitotic checkpoint using Xenopus laevis egg extracts...
January 10, 2018: Cold Spring Harbor Protocols
Chuang Zhang, Wenxue Wang, Wenhui He, Ning Xi, Yuechao Wang, Lianqing Liu
Studies on the contractile dynamics of heart cells have attracted broad attention for the development of both heart disease therapies and cardiomyocyte-actuated micro-robotics. In this study, a linear dynamic model of a single cardiomyocyte cell was proposed at the subcellular scale to characterize the contractile behaviors of heart cells, with system parameters representing the mechanical properties of the subcellular components of living cardiomyocytes. The system parameters of the dynamic model were identified with the cellular beating pattern measured by a scanning ion conductance microscope...
January 9, 2018: Biophysical Journal
Lijuan He, Alexandra Sneider, Weitong Chen, Michelle Karl, Vishnu Prasath, Pei-Hsun Wu, Gunnar Mattson, Denis Wirtz
The study of how mammalian cell division is regulated in a 3D environment remains largely unexplored despite its physiological relevance and therapeutic significance. Possible reasons for the lack of exploration are the experimental limitations and technical challenges that render the study of cell division in 3D culture inefficient. Here, we describe an imaging-based method to efficiently study mammalian cell division and cell-matrix interactions in 3D collagen matrices. Cells labeled with fluorescent H2B are synchronized using the combination of thymidine blocking and nocodazole treatment, followed by a mechanical shake-off technique...
November 29, 2017: Journal of Visualized Experiments: JoVE
Johanna Lindman, Makhala M Khammy, Pia R Lundegaard, Christian Aalkjær, Thomas A Jepps
Microtubules can regulate GPCR (G protein-coupled receptor) signaling in various cell types. In vascular smooth muscle, activation of the β-adrenoceptor leads to production of cAMP to mediate a vasorelaxation. Little is known about the role of microtubules in smooth muscle, and given the importance of this pathway in vascular smooth muscle cells, we investigated the role of microtubule stability on β-adrenoceptor signaling in rat renal and mesenteric arteries. In isometric tension experiments, incubation with the microtubule inhibitors colchicine and nocodazole enhanced isoprenaline-mediated relaxations of renal and mesenteric arteries that the microtubule stabilizer, paclitaxel, prevented...
December 26, 2017: Hypertension
Shuai Shao, Cheng Xiang, Kairong Qin, Aziz Ur Rehman Aziz, Xiaoling Liao, Bo Liu
Disturbed flow can eliminate the alignment of endothelial cells in the direction of laminar flow, and significantly impacts on atherosclerosis in collateral arteries near the bifurcation and high curvature regions. While shear stress induced Rac polarity has been shown to play crucial roles in cell polarity and migration, little is known about the spatiotemporal map of Rac under disturbed flow, and the mechanism of flow-induced cell polarity still needs to be elucidated. In this paper, disturbed flow or laminar flow with 15 dyn/cm2 of average shear stress was applied on bovine aortic endothelial cells (BAECs) for 30 minutes...
2017: PloS One
Juliana Alves-Silva, Isabela P Tavares, Erika S Guimarães, Miriam M Costa Franco, Barbara C Figueiredo, João T Marques, Gary Splitter, Sergio C Oliveira
The microtubule (MT) cytoskeleton regulates several cellular processes related to the immune system. For instance, an intricate intracellular transport mediated by MTs is responsible for the proper localization of vesicular receptors of innate immunity and its adaptor proteins. In the present study, we used nocodazole to induce MTs depolymerization and paclitaxel or recombinant (r) TIR (Toll/interleukin-1 receptor) domain containing protein (TcpB) to induce MT stabilization in bone marrow-derived macrophages infected with Brucella abortus ...
2017: Frontiers in Microbiology
Xihan Guo, Juan Ni, Yuqian Zhu, Tao Zhou, Xiaoling Ma, Jinglun Xue, Xu Wang
Folates comprise the essential B9 vitamin that act as cofactors and cosubstrates in one-carbon metabolism for both biosynthesis and methylation of DNA and RNA. Folate deficiency (FD) has been shown to induce chromosomal instability (CIN), yet the underlying mechanisms are poorly understood. Here, we used human NCM460 colon mucosal cells as a model to investigate the effect of FD on spindle assembly checkpoint (SAC), a cell-cycle regulatory pathway preventing CIN during mitosis. Cells were maintained in medium containing 1...
November 19, 2017: Mutagenesis
Keyvan Mollaeian, Yi Liu, Siyu Bi, Juan Ren
Intracellular network deformation of the cell plays an important role in cellular shape formation. Recent studies suggest that cell reshaping and deformation due to external forces involve cellular volume, pore size, elasticity, and intracellular filaments polymerization degree change. This cell behavior can be described by poroelastic models due to the porous structure of the cytoplasm. In this study, the nanoscale poroelasticity of human mammary basal/claudin low carcinoma cell (MDA-MB-231) was investigated using indentation-based atomic force microscopy...
November 11, 2017: Journal of the Mechanical Behavior of Biomedical Materials
Ping Liu, Violetta Weinreb, Marc Ridilla, Laurie Betts, Pratik Patel, Aravinda M de Silva, Nancy L Thompson, Ken Jacobson
C-type lectins, including dendritic cell-specific intercellular adhesion molecule-3-grabbing nonintegrin (DC-SIGN), are all-purpose pathogen receptors that exist in nanoclusters in plasma membranes of dendritic cells. A small fraction of these clusters, obvious from the videos, can undergo rapid, directed transport in the plane of the plasma membrane at average speeds of more than 1 μm/s in both dendritic cells and MX DC-SIGN murine fibroblasts ectopically expressing DC-SIGN. Surprisingly, instantaneous speeds can be considerably greater...
November 2017: Science Advances
Susanna Krapp, Christian Schuy, Eva Greiner, Irina Stephan, Barbara Alberter, Christina Funk, Manfred Marschall, Christina Wege, Susanne M Bailer, Tatjana Kleinow, Björn Krenz
Geminiviral single-stranded circular DNA genomes replicate in nuclei so that the progeny DNA has to cross both the nuclear envelope and the plasmodesmata for systemic spread within plant tissues. For intra- and intercellular transport, two proteins are required: a nuclear shuttle protein (NSP) and a movement protein (MP). New characteristics of ectopically produced Abutilon mosaic virus (AbMV) MP (MPAbMV ), either authentically expressed or fused to a yellow fluorescent protein or epitope tags, respectively, were determined by localization studies in mammalian cell lines in comparison to plant cells...
November 9, 2017: Viruses
Pablo A Mendoza, Patricio Silva, Jorge Díaz, Cecilia Arriagada, Jimena Canales, Oscar Cerda, Vicente A Torres
The early endosome protein Rab5 was recently shown to promote cell migration by enhancing focal adhesion disassembly through mechanisms that remain elusive. Focal adhesion disassembly is associated to proteolysis of talin, in a process that requires calpain2. Since calpain2 has been found at vesicles and endosomal compartments, we hypothesized that Rab5 stimulates calpain2 activity, leading to enhanced focal adhesion disassembly in migrating cells. We observed that calpain2 co-localizes with EEA1-positive early endosomes and co-immunoprecipitate with EEA1 and Rab5 in A549 lung carcinoma cells undergoing spreading, whereas Rab5 knock-down decreased the accumulation of calpain2 at early endosomal-enriched fractions...
November 3, 2017: Cell Adhesion & Migration
Bing-Bing Hu, Min Chen, Rong-Chen Huang, Yu-Bin Huang, Yang Xu, Wu Yin, Lei Li, Bing Hu
Zebrafish is an excellent model to study central nervous system (CNS) axonal degeneration and regeneration since we can observe these processes in vivo and in real time in transparent larvae. Previous studies have shown that Mauthner cell (M-cell) axon regenerates poorly after mechanical spinal cord injury. Inconsistent with this result, however, we have found that M-cell possesses a great capacity for axon regeneration after two-photon laser ablation. By using ZEISS LSM 710 two-photon microscope, we performed specific unilateral axotomy of GFP labeled M-cells in the Tol-056 enhancer trap line larvae...
February 2018: Experimental Neurology
Dulce Consuelo Guzmán-Ocampo, Rodrigo Aguayo-Ortiz, Lucia Cano-González, Alicia Hernández-Campos, Rafael Castillo, Laura Dominguez
Regulation of microtubule assembly by antimitotic agents is a potential therapeutic strategy for the treatment of cancer, parasite infections, and neurodegenerative diseases. One of these agents is Nocodazole (NZ), which inhibits microtubule polymerization by binding to β-tubulin. NZ was recently co-crystallized in Gallus gallus tubulin, displaying novel information of the interaction features for ligand recognition and stability. In this work, we employed state of the art computational approaches to evaluate the protonation effects of titratable residues and the presence of water molecules in the binding of NZ...
October 23, 2017: ChemMedChem
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"