Abstract:
:We have developed a procedure for sequential silver staining and in situ hybridization to analyze the relationship between the amount of rDNA present in nucleolar organizer regions, as estimated by in situ hybridization, and their level of expression, as estimated by the silver signal. For simplicity we used cells from the insectivorous mole Talpa occidentalis, which have a single pair of nucleolar organizer regions in chromosome pair 3. The relative content of ribosomal cistrons was also related to the hierarchy of activation of the nucleolar organizer regions present in this chromosomal pair. Statistical analyses demonstrated that both the relative level of expression and the activation hierarchy depended mainly on the number of ribosomal cistrons in nucleolar organizer regions. We propose a functional two-step hypothesis, which is consistent with most known data concerning interchromosomal, intercellular and interindividual variation in a number of plant and animal species, including Talpa occidentalis. In step one, the first available transcription factors bind randomly to the ribosomal promoters, such that larger nucleolar organizer regions are more likely to recruit them. In the second step the remaining transcription factors are recruited in a cooperative way, thus completing activation of one nucleolar organizer region, before the next one becomes active.
journal_name
J Cell Scijournal_title
Journal of cell scienceauthors
Zurita F,Jiménez R,Burgos M,de la Guardia RDsubject
Has Abstractpub_date
1998-05-01 00:00:00pages
1433-9eissn
0021-9533issn
1477-9137journal_volume
111 ( Pt 10)pub_type
杂志文章abstract::In adipocytes and muscle cells, the GLUT4 glucose transporter isoform is present in intracellular vesicles which continuously recycle between an intracytoplasmic location and the plasma membrane. It is not clear whether the GLUT4-vesicles represent a specific kind of vesicle or resemble typical secretory granules or s...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1996-06-01 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::Maternally inherited cytoplasmic bacteria have occasionally been observed in embryos and adults of different strains of several Drosophila species. While there is a considerable body of data on the relationship between bacteria and embryo viability, little is known about the behavior of these bacteria during the early...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1994-03-01 00:00:00
abstract::Nearly all intermediate filament (IF) proteins share two sequence motifs located at the N- and the C-terminal ends of their helical rod domain ('coil 1a' and 'coil 2b', respectively). To examine the structural role of the coil 2b motif, we have performed in vitro assembly studies and in vivo microinjection experiments...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1992-05-01 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::We have identified a liver-regulating protein involved in cell contact-mediated regulation of Sertoli cell function by primary spermatocytes in rat testis. Liver-regulating protein was studied using monoclonal antibody L8 prepared from rat primitive biliary epithelial cells. This molecule was located in vivo at the in...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1995-03-01 00:00:00
abstract::The structural events in the stigma and transmitting tissue of Petunia hybrida pistils that accompany compatible and incompatible intraspecific pollinations have been investigated in detail, together with the changes in reserve levels that also take place at this time. Many of these phenomena may be explained in terms...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1979-04-01 00:00:00
abstract::The formation and maturation of membrane carriers that transport cargo from the ER to the Golgi complex involves the sequential action of the coat protein complexes COPII and COPI. Recruitment of COPI to nascent carriers requires activation of ADP-ribosylation factors by a BrefeldinA-sensitive guanine nucleotide excha...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.03173
更新日期:2006-09-15 00:00:00
abstract::The co-repressor proteins SMRT and NCoR concentrate in specific subnuclear compartments and function with DNA-binding factors to inhibit transcription. To provide detailed mechanistic understanding of these activities, this study tested the hypothesis that functional interactions with transcription factors, such as th...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.02450
更新日期:2005-08-01 00:00:00
abstract::Integrin-mediated cell adhesion is central to cell survival, differentiation and motility. Many cell responses induced by integrins require both receptor occupancy and receptor aggregation, and appear to be regulated by both biochemical and biophysical means. Multidomain extracellular matrix molecules may serve to fos...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:2002-04-01 00:00:00
abstract::Hormone secretion by pituitary cells is decreased by roscovitine, an inhibitor of cyclin-dependent kinase 5 (Cdk5). Roscovitine treatment reorganizes cortical actin and ultrastructural analysis demonstrates that roscovitine limits the ability of secretory granules to approach the plasma membrane or one another. Trio, ...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.01333
更新日期:2004-09-15 00:00:00
abstract::Ca(2+) signaling mediated by phospholipase C that produces inositol 1,4,5-trisphosphate [Ins(1,4,5)P(3)] and diacylglycerol (DAG) controls lymphocyte activation. In contrast to store-operated Ca(2+) entry activated by Ins(1,4,5)P(3)-induced Ca(2+) release from endoplasmic reticulum, the importance of DAG-activated Ca(...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.061051
更新日期:2010-03-15 00:00:00
abstract::The function of DAXX, a highly conserved mammalian gene, has remained controversial; this is due, in part, to its identification in a variety of yeast two-hybrid screens. Targeted deletion in the mouse revealed that DAXX is essential for embryonic development. Furthermore, the increased levels of apoptosis observed in...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.00234
更新日期:2003-01-15 00:00:00
abstract::Using epitope mapping we have demonstrated that a high molecular weight protein (Mr approximately 115 x 10(3)) present in brain and spinal cord is a member of the tau family of microtubule-associated proteins. Antibodies directed against the amino-terminal, middle and carboxyl-terminal portions of tau recognize this p...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1991-09-01 00:00:00
abstract::A comparison of stained cytosolic proteins, in vivo 80 S ribosome translation products and in vitro translation products of poly(A)+ RNA from three species of Acetabularia was performed after characterization of their molecular weights and isoelectric points via two-dimensional electrophoresis. A total of 803 stained ...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1983-03-01 00:00:00
abstract::Postsynaptic density protein 95 (PSD-95/SAP-90) is a palmitoylated membrane-associated guanylate kinase that oligomerizes and clusters ion channels and associated signaling machinery at excitatory synapses in brain. However, the mechanism for PSD-95 oligomerization and its relationship to ion channel clustering remain...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.00617
更新日期:2003-08-01 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 Birt-Hogg-Dubé (BHD) syndrome related protein FLCN has recently been implicated in the vesicular trafficking processes by interacting with several Rab family GTPases. In the previous studies, we have shown that FLCN could inhibit the binding of overexpressed PAT1, which is a membrane-bound amino acid transporter, ...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.218792
更新日期:2018-12-19 00:00:00
abstract::The protein product of the gene responsible for ocular albinism type 1, named OA1, is a pigment-cell-specific membrane glycoprotein, displaying features of G-protein-coupled receptors, yet exclusively localized to late endosomes, lysosomes and melanosomes. To dissect the signals responsible for the intracellular local...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.02930
更新日期:2006-05-15 00:00:00
abstract::Muscle regulatory factors activate myogenesis in all vertebrates, but their role has been studied in great detail only in the mouse embryo, where all but myogenin--Myod, Myf5 and Mrf4--are sufficient to activate (albeit not completely) skeletal myogenesis. In the zebrafish embryo, myod and myf5 are required for induct...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.038356
更新日期:2009-02-15 00:00:00
abstract::It remains unclear how GPI-anchored proteins (GPIAPs), which lack cytoplasmic domains, transduce signals triggered by specific ligation. Such signal transduction has been speculated to require the ligated GPIAP to associate with membrane-spanning proteins that communicate with obligate cytoplasmic proteins. Transient ...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.049346
更新日期:2009-11-01 00:00:00
abstract::The invasiveness of mouse lymphocytes and thymocytes, rabbit peritoneal neutrophil granulocytes (PMNs), mouse peritoneal macrophages (both activated and non-activated) and pig endothelial cells was assayed by implanting these cells to the chick wing bud. Cells of each type moved into the wing mesenchyme, although acti...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1979-12-01 00:00:00
abstract::Although the 11.5 kDa Zn(2+)-binding protein (ZnBP, parathymosin-alpha) possesses a functional bipartite nuclear localization signal it was found in most tissues in the cytoplasm. The cultivation of freshly isolated rat hepatocytes for 24 hours under standard conditions was associated with an almost complete transloca...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1999-11-01 00:00:00
abstract::Recent studies have shown that Src-family kinases (SFKs) play an important role in mediating integrin signalling, and the beta3 subunit of alphaIIbbeta3 integrin has been shown to interact with multiple SFK members. Here, we analyzed the interactions and functional consequences of Fyn and Src binding to alphaIIbbeta3....
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.014076
更新日期:2008-05-15 00:00:00
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-...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1996-06-01 00:00:00
abstract::Although endocytosis and exocytosis have been extensively studied in budding yeast, there have been relatively few investigations of these complex processes in the fission yeast Schizosaccharomyces pombe. Here we identify and characterize fission yeast Mug33, a novel Tea1-interacting protein, and show that Mug33 is in...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.084038
更新日期:2011-07-01 00:00:00
abstract::The extracellular environment and tissue architecture contribute to proper cell function and growth control. Cells growing in monolayers on standard polystyrene tissue culture plates differ in their shape, growth rate and response to external stimuli, compared with cells growing in vivo. Here, we showed that the EGFR ...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.054551
更新日期:2009-12-01 00:00:00
abstract::CDC6, a replication licensing protein, is partially exported to the cytoplasm in human cells through phosphorylation by Cdk during S phase, but a significant proportion remains in the nucleus. We report here that human CDC6 physically interacts with ATR, a crucial checkpoint kinase, in a manner that is stimulated by p...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.058693
更新日期:2010-01-15 00:00:00
abstract::Candida albicans is a dimorphic fungus capable of growing as a budding yeast and as a filamentous hypha. We have used the technique of immunofluorescence to study the changes in the microtubule cytoskeleton during the cell cycle in both growth forms. This approach has revealed the presence of an extensive system of mi...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1988-10-01 00:00:00
abstract::Inositol-(1,4,5)-triphosphate receptors (InsP(3)Rs) are ligand-gated Ca(2+) channels that control Ca(2+) release from intracellular stores and play a central role in a wide range of cellular responses. In most epithelial cells, InsP(3)Rs are not uniformly distributed within the endoplasmic reticulum (ER) membrane, wit...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.108738
更新日期:2012-11-15 00:00:00