Abstract：
:Serial sections of mitotic spindles of the marine cryptophycean alga, Cryptomonas, were analysed to determine what types of microtubules they contained and which of these microtubules came close enough to each other (50 nm or less) for the commonly described crossbridging to be possible. Interpolar microtubules were rare (less than or equal to 1%) but from prometaphase through anaphase there was a substantial interpolar framework of free and polar microtubules which came close enough to one another to cross-bridge and generate anaphase spindle elongation by intermicrotubule sliding. However, such elongation would also require some concomitant polar microtubule polymerization. In contrast, only about 12% of the chromosomal microtubules came within bridging distance of interpolar framework microtubules. Thus, assuming that microtubules were accurately fixed in their in vivo positions, crossbridging between chromosomal and interpolar framework microtubules is unlikely to function in chromosome-to-pole movement. In all stages the great majority of chromosomal microtubules were found to extend all the way from the chromatin to the pole. Although the identification of intermicrotubular bridges in section is often ambiguous, the best and most frequent examples of bridges in the present material were between polar microtubules and between chromosomal microtubules but not between the 2 different categories. The spindles also contained 5-nm-diameter microfilaments associated mainly with chromosomal microtubules and occasionally with polar microtubules. A specific model for the possible involvement of these filaments in mitosis is presented.
journal_name
J Cell Scijournal_title
Journal of cell scienceauthors
Oakley BR,Heath IBsubject
Has Abstractpub_date
1978-06-01 00:00:00pages
53-70eissn
0021-9533issn
1477-9137journal_volume
31pub_type
杂志文章abstract：:The Arp2/3 complex is important for morphogenesis in various developmental systems, but specific in vivo roles for this complex in cells that move during morphogenesis are not well understood. We have examined cellular roles for Arp2/3 in the Caenorhabditis elegans embryo. In C. elegans, the first morphogenetic moveme...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.057562
更新日期：2009-11-01 00:00:00
abstract：:In fibroblasts, platelet-derived growth factor (PDGF) and epidermal growth factor (EGF) stimulate the formation of actin-rich, circular dorsal ruffles (CDRs) and phosphatidylinositol 3-kinase (PI3K)-dependent phosphorylation of Akt. To test the hypothesis that CDRs increase synthesis of phosphorylated Akt1 (pAkt), we ...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.220517
更新日期：2018-11-16 00:00:00
abstract：:The role of basal epithelial cells in prostatic function, development and carcinogenesis is unknown. The ability of basal prostatic epithelial cells to acquire a luminal phenotype was explored in vitro using the NRP-152 rat dorsal-lateral prostate epithelial cell line as a model system. NRP-152, which was spontaneousl...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1999-01-01 00:00:00
abstract：:Sequence similarity between the Drosophila segment polarity protein Armadillo and the vertebrate adherens junction protein beta-catenin raised the possibility that adherens junctions function in transduction of intercellular signals like that mediated by Wingless/Wnt-1. To substantiate the sequence similarity, propert...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1993-08-01 00:00:00
abstract：:The translationally controlled tumor protein (TCTP; also known as TPT1 in mammals) is highly conserved and ubiquitously expressed in eukaryotes. It is involved in growth and development, cell cycle progression, protection against cellular stresses and apoptosis, indicating the multifunctional role of the protein. Here...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.206417
更新日期：2018-05-10 00:00:00
abstract：:Following fertilization, there are rapid changes in the appearance of the Fucus egg. Large electron-translucent vesicles (V1) accumulate fibrillar material, and following pronuclear fusion, they are largely electron-opaque. These vesicles (V1) are formed originally in unfertilized eggs by smooth endoplasmic reticulum ...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1976-03-01 00:00:00
abstract：:African trypanosomes undergo extensive changes in cellular morphology, biochemistry and surface antigen expression as they differentiate from their bloodstream form to those forms that colonise the midgut of their tsetse fly vector. If initiated with stumpy-form cells, a non-dividing sub-type of the bloodstream parasi...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1997-10-01 00:00:00
abstract：:Quantitative experimental data from studies of intracellular processing and transport of secretory and membrane proteins are only rarely evaluated using kinetic modelling. Instead, the analysis of such data is usually limited to calculating either the apparent half-life or the transit time. Neither of these parameters...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1989-03-01 00:00:00
abstract：:Casein kinase 1 (CK1) plays central roles in various signal transduction pathways and performs many cellular activities. For many years CK1 was thought to act independently of modulatory subunits and in a constitutive manner. Recently, DEAD box RNA helicases, in particular DEAD box RNA helicase 3 X-linked (DDX3X), wer...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.207316
更新日期：2018-01-04 00:00:00
abstract：:In plants, many nucleus-encoded proteins are targeted to both mitochondria and plastids, and this process is generally mediated by ambiguous N-terminal targeting sequences that are recognized by receptors on both organelles. In many algae, however, plastids were acquired by secondarily engulfing green or red algae, wh...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.116533
更新日期：2012-12-15 00:00:00
abstract：:Abnormal cardiac valve morphogenesis is a common cause of human congenital heart disease. The molecular mechanisms regulating endocardial cell proliferation and differentiation into cardiac valves remain largely unknown, although great progress has been made on the endocardial contribution to the atrioventricular cush...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.116996
更新日期：2013-03-15 00:00:00
abstract：:Rab GTPases are key regulators of intracellular trafficking, and cycle between a GTP-bound active state and a GDP-bound inactive state. This cycle is regulated by guanine-nucleotide exchange factors (GEFs) and GTPase-activating proteins (GAPs). Several efforts have been made in connecting the correct GEFs and GAPs to ...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.216630
更新日期：2018-09-03 00:00:00
abstract：:During directed cell migration, the movement of the nucleus is coupled to the forward progression of the cell. The microtubule motor cytoplasmic dynein is required for both cell polarization and cell motility. Here, we investigate the mechanism by which dynein contributes to directed migration. Knockdown of dynein slo...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.033878
更新日期：2008-10-01 00:00:00
abstract：:We report a fast method for the isolation of homogeneous C-protein from bovine skeletal muscle. In electron micrographs C-protein appears as short rods with a relatively uniform length of about 50 nm. Protein sequencing shows a single N-terminal sequence. Radio-labelled C-protein strongly decorates titin II and myosin...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1992-08-01 00:00:00
abstract：:The large GTPase dynamin, long known for its role in endocytosis, has most recently been implicated as a facilitator of cell migration and invasion. Recent observations link dynamin to the cycle of membrane expansion and retraction essential for cell motility. Its role in actin polymerization, membrane deformation and...
journal_title：Journal of cell science
pub_type： 杂志文章,评审
doi：10.1242/jcs.02963
更新日期：2006-05-01 00:00:00
abstract：:Rabbit muscle is a major source of material for biochemical experiments and spin labelling studies of contraction, and so it is important to establish how closely this material resembles the frog and fish muscles usually used for structural studies. Previous studies have shown that relaxed rabbit muscle thick filament...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1993-07-01 00:00:00
abstract：:The microtubule-associated protein tau interacts with the SH3 domain of non-receptor Src family protein tyrosine kinases. A potential consequence of the SH3 interaction is the upregulation of tyrosine kinase activity. Here we investigated the activation of Src or Fyn by tau, both in vitro and in vivo. Tau increased th...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.03378
更新日期：2007-03-01 00:00:00
abstract：:The molecular motor dynein is essential for mitotic spindle orientation, which defines the axis of cell division. The light intermediate chain subunits, LIC1 and LIC2, define biochemically and functionally distinct vertebrate dynein complexes, with LIC2-dynein playing a crucial role in ensuring spindle orientation. We...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.239673
更新日期：2020-06-23 00:00:00
abstract：:Homologous to E6AP C-terminus (HECT) E3 ubiquitin ligases play a critical role in various cellular pathways, including but not limited to protein trafficking, subcellular localization, innate immune response, viral infections, DNA damage responses and apoptosis. To date, 28 HECT E3 ubiquitin ligases have been identifi...
journal_title：Journal of cell science
pub_type： 杂志文章,评审
doi：10.1242/jcs.228072
更新日期：2020-04-07 00:00:00
abstract：:Epidermal growth factor receptor (EGFR) ligands undergo a complex series of processing events during their maturation to active signaling proteins. Like its mammalian homologs, the predominant Drosophila EGFR ligand Spitz is produced as a transmembrane pro-protein. In the secretory pathway, Spitz is cleaved within its...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.131169
更新日期：2013-10-01 00:00:00
abstract：:MicroRNAs are short non-coding RNAs involved in post-transcriptional regulation of multiple messenger RNA targets. The miR-1/miR-206 family is expressed during skeletal muscle differentiation and is an integral component of myogenesis. To better understand miR-1/miR-206 function during myoblast differentiation we iden...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.101758
更新日期：2012-08-01 00:00:00
abstract：:We show that muscle satellite cells, traditionally considered as committed myogenic precursors, are comprised of Pax7-expressing progenitors that preserve a mesenchymal repertoire extending beyond a mere myogenic potential. Mouse satellite cells from freshly isolated single myofibers, cultured individually in serum-ri...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.01419
更新日期：2004-10-15 00:00:00
abstract：:The tachyzoite stage of the protozoan parasite Toxoplasma gondii has two populations of microtubules: spindle microtubules and subpellicular microtubules. To determine how these two microtubule populations are regulated, we investigated microtubule behavior during the cell cycle following treatment with microtubule-di...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：2002-03-01 00:00:00
abstract：:Antithrombin inhibits chemokine-induced migration of neutrophils by activating heparan sulfate proteoglycan-dependent signaling. Whether antithrombin affects migration of other types of leukocytes is not known. We investigated the effects of antithrombin on spontaneous and chemokine-triggered migration of lymphocytes ...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：2002-01-01 00:00:00
abstract：:Cadherin has an intimate spatial relationship with actin filaments (AF) in various types of cells, forming the cell-to-cell adherens junction (AJ). We compared the AJ/AF relationship between non-polarized fibroblasts (NRK cells) and polarized epithelial cells (MTD-1A cells). E/P-cadherin, alpha-catenin, ZO-1 and vincu...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1995-01-01 00:00:00
abstract：:Recently, we demonstrated in cultured endothelial cells and in vivo that deficiency of an isoform of intersectin-1, ITSN-1s, impairs caveolae and clathrin-mediated endocytosis and functionally upregulates compensatory pathways and their morphological carriers (i.e. enlarged endocytic structures, membranous rings or tu...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.163030
更新日期：2015-04-15 00:00:00
abstract：:The GGGGCC (G4C2) repeat expansion mutation in the C9ORF72 gene is the most common genetic cause of frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS). Transcription of the repeat and formation of nuclear RNA foci, which sequester specific RNA-binding proteins, is one of the possible pathological me...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.224303
更新日期：2019-03-07 00:00:00
abstract：:During pre-mRNA splicing, introns are removed and exons are ligated to form an mRNA. Exon choice is determined by different nuclear protein concentrations varying among tissues and cell types or by developmental stage. These can be altered by different cellular circumstances such as physiological stimuli, environmenta...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.01720
更新日期：2005-03-15 00:00:00
abstract：:A number of structural and functional subnuclear compartments have been described, including regions exclusive of chromosomes previously hypothesized to form a reactive nuclear space. We have now explored this accessible nuclear space and interchromosomal nucleoplasmic domains experimentally using Xenopus vimentin eng...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1998-05-01 00:00:00
abstract：:Mammalian Staufen2 (Stau2) is involved in mRNA transport in neurons. Here, we report that Stau2 is a double-stranded RNA-binding protein that is mainly expressed in the brain. We show that Stau2 is found in the somatodendritic compartment of neurons. In dendrites, Stau2 is aligned on individual tracts and colocalizes ...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：2002-08-15 00:00:00
