Abstract:
:Immediately following embryonic cleavage, the cells of Astrephomene have four equal-sized basal bodies, two of which are connected by a striated distal fibre and two striated proximal fibres. The four microtubular rootlets, which alternate between having 3/1 and 2 members, are arranged cruciately. The two basal bodies that are connected by the striated fibres then extend into flagella, while the two accessory basal bodies are now markedly shorter. At this stage the flagellar apparatus has 180 degrees rotational symmetry and is very similar to the flagellar apparatus of the unicellular Chlamydomonas and related algae. Development proceeds with a number of concurrent events. The basal bodies begin to separate at their proximal ends and become nearly parallel. Each striated proximal fibre detaches at one end from one of the basal bodies. Each half of the flagellar apparatus, which consists of a flagellum and attached basal body, an accessory basal body, two rootlets and a striated fibre (formerly one of the proximal striated fibres), rotates about 90 degrees, the two halves rotating in opposite directions. An electron-dense strut forms near one two-membered rootlet and grows past both basal bodies. During this time a fine, fibrous component appears between newly developed spade-like structures and associated amorphous material connected to each basal body. The basal bodies continue to separate as the distal fibre stretches and finally detaches from one of them. These processes result in the loss of the 180 degree rotational symmetry present in previous stages. Although the flagella continue to separate, there is no further reorganization of the components of the flagellar apparatus. In the mature cell of Astrephomene, the two flagella are inserted separately and are parallel. The four microtubular rootlets are no longer arranged cruciately. Three of the rootlets are nearly parallel, while the fourth is approximately perpendicular to the other three. A straited fibre connects each basal body to the underside of the strut. These fibres run in the direction of the effective stroke of the flagella and might be important either in anchoring the basal bodies or in the initiation of flagellar motion. Unlike the case in the unicellular Chlamydomonas, the two flagella beat in the same direction and in parallel planes. The flagella of a given cell may or may not beat in synchrony. The combination of this type of flagellar motion and the parallel, separate flagella appears to be suited to the motion of this colonial organism.
journal_name
J Cell Scijournal_title
Journal of cell scienceauthors
Hoops HJ,Floyd GLsubject
Has Abstractpub_date
1983-09-01 00:00:00pages
21-41eissn
0021-9533issn
1477-9137journal_volume
63pub_type
杂志文章abstract::The Wnt signal transduction pathway regulates various aspects of embryonal development and is involved in cancer formation. Wnts induce the stabilisation of cytosolic (beta)-catenin, which then associates with TCF transcription factors to regulate expression of Wnt-target genes. At various levels the Wnt pathway is su...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:2000-03-01 00:00:00
abstract::When malignant human cells are crossed with diploid human keratinocytes, malignancy, as defined by progressive growth in vivo, is suppressed so long as the hybrid cells continue to produce involucrin, a protein that characterizes terminal differentiation in the keratinocyte. When, on continued cultivation in vitro, th...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1987-04-01 00:00:00
abstract::The LEM domain (for lamina-associated polypeptide, emerin, MAN1 domain) defines a group of nuclear proteins that bind chromatin through interaction of the LEM motif with the conserved DNA crosslinking protein, barrier-to-autointegration factor (BAF). Here, we describe a LEM protein annotated in databases as 'Ankyrin r...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.098392
更新日期:2012-02-15 00:00:00
abstract::Plasmid DNA or artificial mRNA injected intramuscularly into skeletal muscle via a 27 g needle expressed transgenes at relatively efficient levels in skeletal myofibers and cardiac cells. In the present study, several approaches were used to determine the mechanism of cellular uptake. After exposure of naked plasmid D...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1992-12-01 00:00:00
abstract::Human cytomegalovirus (HCMV) establishes life-long latent infection in hematopoietic progenitor cells and circulating monocytes in infected individuals. Myeloid differentiation coupled with immune dysregulation leads to viral reactivation, which can cause severe disease and mortality. Reactivation of latent virus requ...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.254268
更新日期:2021-01-25 00:00:00
abstract::Recent biochemical and molecular approaches have begun to establish the protein interactions that lead to desmosome assembly. To determine whether these associations occur in native desmosomes we have performed ultrastructural localisation of specific domains of the major desmosomal components and have used the result...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1999-12-01 00:00:00
abstract::Start is the main decision point in the eukaryotic cell cycle at which cells commit to a new round of cell division. It involves the irreversible activation of a transcriptional programme through the inactivation of Start transcriptional repressors: the retinoblastoma family in mammals, or Whi5 and its recently identi...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.251413
更新日期:2020-12-21 00:00:00
abstract::The mammalian inactive X chromosome (Xi) is a model for facultative heterochromatin. Increased DNA compaction for the Xi, and for facultative heterochromatin in general, has long been assumed based on recognition of a distinct Barr body using nucleic-acid staining. This conclusion has been challenged by a report revea...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.026104
更新日期:2008-04-01 00:00:00
abstract::Triosephosphate isomerase (TPI) is a glycolytic enzyme that converts dihydroxyacetone phosphate (DHAP) into glyceraldehyde 3-phosphate (GAP). Glycolytic enzyme dysfunction leads to metabolic diseases collectively known as glycolytic enzymopathies. Of these enzymopathies, TPI deficiency is unique in the severity of neu...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.124586
更新日期:2013-07-15 00:00:00
abstract::The HB2 cell line, developed from luminal epithelial cells cultured from milk, forms ball-like structures in collagen gels which show a uniform branching response to hepatocyte growth factor. The alpha2beta1 integrin is the major integrin expressed by luminal epithelial cells, and the role of this integrin in mammary ...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1998-02-01 00:00:00
abstract::An essential step in mammalian fertilisation is the sperm acrosome reaction (AR) - exocytosis of a single large vesicle (the acrosome) that surrounds the nucleus at the apical sperm head. The acrosomal and plasma membranes fuse, resulting in both the release of factors that might facilitate penetration of the zona pel...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.030379
更新日期:2008-07-01 00:00:00
abstract::Mammalian Delta9 stearoyl-CoA desaturase 1 (SCD1) is a key enzyme in the biosynthesis of mono-unsaturated fatty acids in the endoplasmic reticulum (ER). It is a short-lived multispanning ER membrane protein, reported to be degraded by the ubiquitin-proteasome-independent pathway. We have examined SCD1 protein degradat...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.02951
更新日期:2006-06-01 00:00:00
abstract::In primary cultures of rat cerebellar granule cells with a functional network of glutamatergic neurons, the expression pattern of the different subunits of nitric-oxide (NO)-sensitive guanylyl cyclase changes during cell differentiation. These cells express the alpha1, alpha2 and beta1 subunits of NO-sensitive guanyly...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.00620
更新日期:2003-08-01 00:00:00
abstract::Dispersion of neural crest cells and their ultimate regroupment into peripheral ganglia are associated with precisely coordinated regulations both in time and space of the expression and function of cell adhesion receptors. In particular, the disappearance of N-cadherin from the cell surface at the onset of migration ...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1995-12-01 00:00:00
abstract::When green cells of Euglena gracilis, strain Z, were light-grown for several months on a solid medium containing an excess of sodium acetate (1.0% instead of the normal 0.1%), some 30% of the cells were colourless. The 'acetate-bleached' organisms, isolated by plating methods and subsequently incubated in the light in...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1983-05-01 00:00:00
abstract::Myofibrillar proteins assemble to form the highly ordered repetitive contractile structural unit known as a sarcomere. Studies of myogenesis in vertebrate cell culture and embryonic developmental systems have identified some of the processes involved during sarcomere formation. However, isoform changes during vertebra...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.01024
更新日期:2004-04-01 00:00:00
abstract::Electrical synapses (gap junctions) rapidly transmit signals between neurons and are composed of connexins. In neurons, connexin36 (Cx36) is the most abundant isoform; however, the mechanisms underlying formation of Cx36-containing electrical synapses are unknown. We focus on homocellular and heterocellular gap juncti...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.133066
更新日期:2014-03-15 00:00:00
abstract::Smooth muscle cells may be isolated from the taenia coli muscle of the guinea pig which, when made permeable by treatment with Triton X-100 (0-05%) show a sensitivity to Ca for contraction with MgATP. The rate of contraction, about 10 micron s-1, corresponds closely to the maximum velocity of shortening of the intact ...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1977-04-01 00:00:00
abstract::Low doses of the muscarinic agonist pilocarpine (0.1-1 microM) and the beta-adrenergic agonist isoproterenol (0.5-4 nM) stimulate a minor regulated secretory pathway for salivary proteins in rat parotid lobules. Newly synthesized proteins (labeled biosynthetically) are selectively discharged, and they are secreted in ...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1996-10-01 00:00:00
abstract::Melanotransferrin (p97) is an iron-binding membrane glycoprotein with 40% homology to transferrin and lactoferrin. It was first identified on the basis of its high level of expression in melanoma cells, as compared to normal melanocytes. It is also present in many cultured cell types. In normal tissues, p97 is express...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1993-04-01 00:00:00
abstract::The neural cell adhesion molecule NCAM plays an important role during neural development and in the adult brain. To study the intracellular trafficking of NCAM in neurons, two major isoforms, NCAM140 or NCAM180, were expressed in primary cortical neurons and in the rat B35 neuroblastoma cell line. NCAM was endocytosed...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.019729
更新日期:2007-11-15 00:00:00
abstract::During the assembly of Plasmodium falciparum merozoites within the schizont stage, the parasite synthesizes and positions three sets of secretory vesicles (rhoptries, micronemes and dense granules) that are active during red cell invasion. There are up to 40 micronemes per merozoite, shaped like long-necked bottles, a...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.00665
更新日期:2003-09-15 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::In order to determine whether fibronexus morphogenesis is involved in the establishment of more normal cellular morphology and substrate adhesion patterns in Nil/HSV transformed fibroblasts induced by treatment with exogenous fibronectin (FN), this system was studied with electron microscopy (EM), immunocytochemistry,...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1982-08-01 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::Intracellular membrane fusion occurs with exquisite coordination and specificity. Each fusion event requires three basic components: Rab-GTPases organize the fusion site; SNARE proteins act during fusion; and N-ethylmaleimide-sensitive factor (NSF) plus its cofactor alpha-SNAP are required for recycling or activation ...
journal_title:Journal of cell science
pub_type: 杂志文章,评审
doi:10.1242/jcs.02561
更新日期:2005-09-01 00:00:00
abstract::We have investigated the effect of nitric oxide (NO) on apoptosis in Swiss 3T3 fibroblasts and compared it to the effect of the nitrosonium cation (NO+). Both species induced apoptosis, confirmed by electron microscopy, propidium iodide staining, DNA laddering and activation of caspases. The kinetics of triggering apo...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1997-09-01 00:00:00
abstract::Mitochondrial DNA (mtDNA) replication and transcription are crucial for cell function, but these processes are poorly understood at the single-cell level. We describe a novel fluorescence in situ hybridization protocol, called mTRIP (mitochondrial transcription and replication imaging protocol), that reveals simultane...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.114322
更新日期:2013-02-15 00:00:00
abstract::The phagocytic ability of macrophages empowers them to enforce innate immunity. RAW264.7, THP-1 and peripheral blood mononuclear cell-derived macrophages display considerable variability with regards to their phagocytic ability. We identify the underlying causes that attenuate the phagocytic abilities of a macrophage....
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.236471
更新日期:2020-03-02 00:00:00
abstract::Cytoplasm of Paramecium caudatum syngen 3 in the period of sexual immaturity was effective in inducing immaturity when injected into mating-reactive cells of other syngens of P. caudatum. When immature cytoplasm of P. caudatum was injected into mature cells of P. multimicronucleatum, immaturity was also induced in the...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1979-04-01 00:00:00