Abstract:
:Nascent transcripts in permeabilized HeLa cells were elongated by approximately 30-2,000 nucleotides in Br-UTP or biotin-14-CTP, before incorporation sites were immunolabelled either pre- or post-embedding, and visualized by light or electron microscopy. Analogues were concentrated in approximately 2,100 (range 2,000-2,700) discrete sites attached to a nucleoskeleton and surrounded by chromatin. A typical site contained a cluster (diameter 71 nm) of at least 4, and probably about 20, engaged polymerases, plus associated transcripts that partially overlapped a zone of RNA polymerase II, ribonucleoproteins, and proteins rich in thiols and acidic groups. As each site probably contains many transcription units, these results suggest that active polymerases are confined to these sites, which we call transcription 'factories'. Results are consistent with transcription occurring as templates slide past attached polymerases, as nascent RNA is extruded into the factories.
journal_name
J Cell Scijournal_title
Journal of cell scienceauthors
Iborra FJ,Pombo A,Jackson DA,Cook PRsubject
Has Abstractpub_date
1996-06-01 00:00:00pages
1427-36eissn
0021-9533issn
1477-9137journal_volume
109 ( Pt 6)pub_type
杂志文章abstract::Genetic analysis in the yeast Schizosaccharomyces pombe has shown that three genes cdc18, cut5, and cdt1, are essential for DNA synthesis and also for the checkpoint control that couples completion of DNA replication to the onset of mitosis. To test whether assembly of the replication initiation complex is an importan...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1995-09-01 00:00:00
abstract::Clathrin-mediated endocytosis requires cargo-specific adaptor proteins that recognize specific receptors and recruit them into coated pits. ARH [also called low-density lipoprotein receptor (LDLR) adaptor protein] serves as an adaptor for LDLR endocytosis in liver. However, ARH is dispensable for LDL uptake by some ot...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.03217
更新日期:2006-10-15 00:00:00
abstract::A dysregulation in the clearance of apoptotic material is considered a major pathogenetic factor for the emergence of autoimmune diseases. Apoptotic-cell-derived membrane microparticles (AdMPs), which are released from the cell surface during apoptosis, have been implicated in the pathogenesis of autoimmunity. Also of...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.162735
更新日期:2015-07-15 00:00:00
abstract::Ryanodine receptors (RyRs) are expressed on the endoplasmic reticulum of many cells, where they form intracellular Ca2+-release channels that participate in the generation of intracellular Ca2+ signals. Here we report studies on the intracellular localisation and functional properties of transfected RyR1 or RyR3 chann...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:2002-06-15 00:00:00
abstract::In order to replicate, most pathogens need to enter their target cells. Many viruses enter the host cell through an endocytic pathway and hijack endosomes for their journey towards sites of replication. For delivery of their genome to the host cell cytoplasm and to avoid degradation, viruses have to escape this endoso...
journal_title:Journal of cell science
pub_type: 杂志文章,评审
doi:10.1242/jcs.216259
更新日期:2018-08-03 00:00:00
abstract::The development of DNA microarrays to study simultaneously the level of mRNA expressed from thousands of genes offers great promise to cell biologists. Microarrays can be used to gain detailed information about transcriptional changes involved in a specific pathway, potentially leading to the identification of novel c...
journal_title:Journal of cell science
pub_type: 杂志文章,评审
doi:
更新日期:2000-12-01 00:00:00
abstract::Meiotic cell cycles differ from mitotic cell cycles in that the former lack S-phase in the interphase between meiosis I and meiosis II. To obtain clues for mechanisms involved in the cell cycle regulation unique to meiosis, we have examined changes in chromosomal morphology and H1 kinase activity during a meiotic peri...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1994-11-01 00:00:00
abstract::Maintenance of epithelial polarity depends on the correct localization and levels of polarity determinants. The evolutionarily conserved transmembrane protein Crumbs is crucial for the size and identity of the apical membrane, yet little is known about the molecular mechanisms controlling the amount of Crumbs at the s...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.174573
更新日期:2015-12-15 00:00:00
abstract::We have identified a novel mammalian protein, MIR1, with microtubule-binding activity. MIR1 is a relative of MID1/midin, the protein implicated in Opitz G/BBB syndrome. In tissue culture cells, MIR1 is enriched at the centrosome. MIR1 dissociates from centrosomes at the G2/M transition and is recruited back to spindle...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:2002-09-01 00:00:00
abstract::A simplified model of TIRF optics was used to quantitate the relative membrane/substratum separation distances from the spatial pattern of TIRF image brightness. Phase-contrast and total internal reflection fluorescence microscopy (TIRFM) images were collected of bovine aortic endothelial cells (BAEC) plated onto glas...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1992-10-01 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::Localization of mRNAs is currently thought to be partially responsible for molecular sorting to specific compartments within the cell. In mammalian cells the best-studied example is the beta-actin mRNA that is localized to the cell processes, and its localization is necessary in migratory responses of cells. It is rea...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1998-10-01 00:00:00
abstract::The coordinated cellular responses to physiological stress are known to be effected in part by the activation of heat-shock factor 1, a transcriptional activator protein capable of binding to, and inducing transcription from genes containing heat shock elements. Other stress responsive signal transduction pathways als...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1996-05-01 00:00:00
abstract::Basonuclin is a zinc finger protein mainly expressed in keratinocytes of the basal layer of epidermis and the outer root sheath of hair follicles. It is also found in abundance in the germ cells of testis and ovary. In cultured keratinocytes, basonuclin is associated with chromatin in all phases of the cell cycle, inc...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1999-09-01 00:00:00
abstract::Cardiac fibrosis is linked to fibroblast-to-myofibroblast phenoconversion and proliferation but the mechanisms underlying this are poorly understood. Ski is a negative regulator of TGF-β-Smad signaling in myofibroblasts, and might redirect the myofibroblast phenotype back to fibroblasts. Meox2 could alter TGF-β-mediat...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.126722
更新日期:2014-01-01 00:00:00
abstract::Naegleria gruberi is a single-celled eukaryote best known for its remarkable ability to form an entire microtubule cytoskeleton de novo during its metamorphosis from an amoeba into a flagellate, including basal bodies (equivalent to centrioles), flagella and a cytoplasmic microtubule array. Our publicly available full...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.077453
更新日期:2010-12-01 00:00:00
abstract::Errors in mitotic chromosome segregation can lead to DNA damage and aneuploidy, both hallmarks of cancer. To achieve synchronous error-free segregation, mitotic chromosomes must align at the metaphase plate with stable amphitelic attachments to microtubules emanating from opposing spindle poles. The astrin-kinastrin (...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.251025
更新日期:2021-01-08 00:00:00
abstract::In the central nervous system, oligodendrocytes synthesize vast amounts of myelin, a multilamellar membrane wrapped around axons that dramatically enhances nerve transmission. A complex apparatus appears to coordinate trafficking of proteins and lipids during myelin synthesis, but the molecular interactions involved a...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.02785
更新日期:2006-03-01 00:00:00
abstract::In the developing Drosophila eye, the centrioles of the differentiating retinal cells are not surrounded by the microtubule-nucleating γ-tubulin, suggesting that they are unable to organize functional microtubule-organizing centers. Consistent with this idea, Cnn and Spd-2, which are involved in γ-tubulin recruitment,...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.211441
更新日期:2018-02-22 00:00:00
abstract::Yeast Reb1 and its mammalian ortholog TTF1 are conserved Myb-type DNA-binding proteins that bind to specific sites near the 3'-end of rRNA genes (rDNA). Here, they participate in the termination of transcription driven by RNA polymerase I and block DNA replication forks approaching in the opposite direction. We found ...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.070987
更新日期:2011-01-01 00:00:00
abstract::Bone morphogenetic protein (BMP)-6 is a member of the transforming growth factor (TGF)-(&bgr;) superfamily, and is most similar to BMP-5, osteogenic protein (OP)-1/BMP-7, and OP-2/BMP-8. In the present study, we characterized the endogenous BMP-6 signaling pathway during osteoblast differentiation. BMP-6 strongly indu...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1999-10-01 00:00:00
abstract::Glutathione (GSH) levels progressively decline during aging and in neurodegenerative disorders. However, the contribution of such event in mediating neuronal cell death is still uncertain. In this report, we show that, in neuroblastoma cells as well as in primary mouse cortical neurons, GSH decrease, induced by buthio...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.077149
更新日期:2011-04-01 00:00:00
abstract::Tau is a neuronal microtubule-associated protein that appears to function in the formation and maintenance of axons by influencing microtubule organisation. Tau is a phosphoprotein and is more heavily phosphorylated in fetal than in adult brain, and is also hyperphosphorylated in Alzheimer's disease where it forms the...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1996-06-01 00:00:00
abstract::The specification of organs, tissues and cell types results from cell fate restrictions enacted by nuclear transcription factors under the control of conserved signaling pathways. The progenitor epithelium of the Drosophila compound eye, the eye imaginal disc, is a premier model for the study of such processes. Early ...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.237834
更新日期:2020-05-26 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::Vimentin expression in human mammary epithelial MCF10A cells was examined as a function of their migratory status using an in vitro wound-healing model. Analysis of the trajectories of the cells and their migratory speeds by time lapse-video microscopy revealed that vimentin mRNA and protein expression were exclusivel...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1999-12-01 00:00:00
abstract::Xenopus embryos initiate replication at random closely spaced sites until a certain concentration of nuclei is achieved within the embryo, after which fewer, more specific chromosomal sites are utilized as origins. We have examined the relationship between nucleo-cytosolic ratio and origin specification when Chinese h...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1998-10-01 00:00:00
abstract::Activity of AURKA is controlled through multiple mechanisms including phosphorylation, ubiquitin-mediated degradation and allosteric interaction with TPX2. Activity peaks at mitosis, before AURKA is degraded during and after mitotic exit in a process strictly dependent on the APC/C coactivator FZR1. We used FZR1 knock...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.243071
更新日期:2020-06-16 00:00:00
abstract::Murine mesenchymal stem cells are capable of differentiating in vitro into different lineages under stimulation with certain cytokines, growth factors and chemicals. However, the true capacity of these cells to contribute to different cell-types in vivo is still unclear, especially under minimal injury conditions. In ...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.01488
更新日期:2004-11-01 00:00:00
abstract::Members of the ezrin-radixin-moesin (ERM) family of proteins are involved in multiple aspects of cell migration by acting both as crosslinkers between the membrane, receptors and the actin cytoskeleton, and as regulators of signalling molecules that are implicated in cell adhesion, cell polarity and migration. Increas...
journal_title:Journal of cell science
pub_type: 杂志文章,评审
doi:10.1242/jcs.133108
更新日期:2014-01-15 00:00:00