Abstract：
:Electron-microscope autoradiography has been used to obtain information on the localization of DNA labelled with [3H]thymidine in chloroplasts known to be replicating and concomitantly synthesizing and segregating DNA, in cultured leaf disks. The studies were made using both Microdol-X developer and a 'compact' developer which gave a smaller grain size. About 80% of the grains were associated with the granal membranes and with presumptive DNA regions (3-nm fibril material in clear areas). Few grains occurred in association with the chloroplast envelope. We suggest that the DNA of chloroplasts is associated with the grana lamellae and extends into the stroma. Some light-microscope autoradiographs of whole chloroplasts show spiral or helical-like labelling patterns. We interpret these patterns as demonstration of the possibility that DNA occurs along the length of a continuous lamellar membrane system. Chloroplast fractionation experiments provided data consistent with the electron-microscope autoradiographic studies as most of the label was associated with chlorophyll-containing lamellae. We consider an association of chloroplast DNA molecules along the length of a continuous lamellar system would ensure an orderly segregation of DNA to daughter chloroplasts, during the binary fission of spinach chloroplasts by constriction division.
journal_name
J Cell Scijournal_title
Journal of cell scienceauthors
Rose RJ,Possingham JVkeywords:
subject
Has Abstractpub_date
1976-03-01 00:00:00pages
341-55issue
2eissn
0021-9533issn
1477-9137journal_volume
20pub_type
杂志文章abstract：:Pharmacological inhibitors of JNK (SP600125) and p38 (PD169316) sensitize tumor cells to Fas-mediated apoptosis. PD169316 is less potent than SP600125 and diminishes its effect when present together. Because the p38 isoforms that promote (p38alpha) or inhibit (p38beta) apoptosis are both suppressed by PD169316, we inv...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.01573
更新日期：2004-12-15 00:00:00
abstract：:Junctional adhesion molecules (JAMs) are members of an immunoglobulin subfamily expressed by leukocytes and platelets as well as by epithelial and endothelial cells, in which they localize to cell-cell contacts and are specifically enriched at tight junctions. The recent identification of extracellular ligands and int...
journal_title：Journal of cell science
pub_type： 杂志文章,评审
doi：10.1242/jcs.00930
更新日期：2004-01-01 00:00:00
abstract：:Monoclonal mouse hybridoma antibodies were obtained for secreted cellular fibronectin (cFn) from A8387 fibrosarcoma cells. One of them, 52-DH1 (DH), reacted exclusively with cFns but not with plasma Fns (pFns) in immunoblotting and solid-phase EIA. The DH antibody also recognized thermolysin cFn fragments and beta-gal...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1987-11-01 00:00:00
abstract：:The adaptor protein SETA/CIN85/Ruk is involved in regulating diverse signal transduction pathways, including the internalization of tyrosine kinase receptors via the Cbl ubiquitin ligases, and attenuating PI3K activity by interaction with its regulatory subunit. Here we present evidence for a new aspect of SETA functi...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.00522
更新日期：2003-07-15 00:00:00
abstract：:Quantitative studies on the adhesive properties of transformed cells have yielded inconclusive and sometimes contradictory results. The present investigation has examined adhesive interactions between normal human fibroblasts, established as well as virus-transformed animal cell lines, and human tumour-derived cell li...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1978-10-01 00:00:00
abstract：:RIF1 controls both DNA replication timing and the DNA double-strand break (DSB) repair pathway to maintain genome integrity. However, it remains unclear how RIF1 links these two processes following exposure to ionizing radiation (IR). Here, we show that inhibition of homologous recombination repair (HRR) by RIF1 occur...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.240036
更新日期：2020-06-22 00:00:00
abstract：:Signalling by target-derived neurotrophins is essential for the correct development of the nervous system and its maintenance throughout life. Several aspects concerning the lifecycle of neurotrophins and their receptors have been characterised over the years, including the formation, endocytosis and trafficking of si...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.242412
更新日期：2020-03-30 00:00:00
abstract：:Previously, we documented the role of the programmed death-1 (PD-1, also known as PDCD1) pathway in macrophage apoptosis and the downregulation of this signaling during infection by the intra-macrophage parasite Leishmania donovani However, we also found that, during the late phase of infection, PD-1 expression was si...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.226274
更新日期：2019-05-02 00:00:00
abstract：:Rac1 and Rac3 are highly homologous regulatory proteins that belong to the small GTPases of the Rho family. Previously, we showed that Rac3 induces cell rounding and prevents neuronal differentiation, in contrast to its close relative Rac1, which stimulates cell spreading and neuritogenesis. To explain these opposing ...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.039958
更新日期：2009-06-15 00:00:00
abstract：:The polarized functions of epithelia require an intact tight junction (TJ) to restrict paracellular movement and to separate membrane proteins into specific domains. TJs contain scaffolding, integral membrane and signaling proteins, but the mechanisms that regulate TJs and their assembly are not well defined. Galpha12...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.014878
更新日期：2008-03-15 00:00:00
abstract：:Cell migration is essential for normal development and many pathological processes. Rho-family small GTPases play important roles in this event. In particular, Rac regulates lamellipodia formation at the leading edge during migration. The small GTPase RhoG activates Rac through its effector ELMO and the ELMO-binding p...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.02720
更新日期：2006-01-01 00:00:00
abstract：:In adherent cells, the relevance of a physical mechanotransduction pathway provided by the perinuclear actin cap stress fibers has recently emerged. Here, we investigate the impact of a functional actin cap on the cellular adaptive response to topographical cues and uniaxial cyclic strain. Lmna-deficient fibroblasts a...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.184838
更新日期：2017-02-15 00:00:00
abstract：:Cofilin has emerged as a key regulator of actin dynamics at the leading edge of motile cells. Through its actin-severing activity, it creates new actin barbed ends for polymerization and also depolymerizes old actin filaments. Its function is tightly regulated in the cell. Spatially, its activity is restricted by othe...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.01631
更新日期：2005-01-01 00:00:00
abstract：:Endoblast and hypoblast tissue, dissected from early chick embryos, was explanted and cultured on glass or plastic substrata. These tissues grew rapidly to form epithelial sheets. Under the same conditions, mesoderm, dissected without the aid of dissociating agents, grew poorly. After 24 h in culture, the mesoderm exp...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1980-08-01 00:00:00
abstract：:Sorting endosomes (SEs) are the regulatory hubs for sorting cargo to multiple organelles, including lysosome-related organelles, such as melanosomes in melanocytes. In parallel, melanosome biogenesis is initiated from SEs with the processing and sequential transport of melanocyte-specific proteins toward maturing mela...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.216226
更新日期：2018-09-20 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：:HSP27 and alphaB-crystallin are both members of the small heat shock protein family. alphaB-crystalllin has been proposed to modulate intermediate filaments and recently a mutation in alphaB-crystallin has been identified as the genetic basis of desmin related myopathy. This disease is characterised in its pathology b...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1999-07-01 00:00:00
abstract：:The purpose of our studies was to determine the fate of different cell types present in early primary cultures of tracheal epithelial cells and, if possible, to elucidate the role they play in the establishment of the cultures. Epithelial cells were isolated from rat tracheas with 0.5% Pronase and were cultured on col...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1985-03-01 00:00:00
abstract：:Cannabinoid receptors (CBRs) belong to the G protein-coupled receptor superfamily, and activation of CBRs in salivary cells inhibits agonist-stimulated salivation and modifies saliva content. However, the role of different CBR subtypes in acinar cell physiology and in intracellular signalling remains unclear. Here, we...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.088930
更新日期：2012-04-15 00:00:00
abstract：:Cellular senescence suppresses cancer by arresting cells at risk of malignant tumorigenesis. However, senescent cells also secrete molecules that can stimulate premalignant cells to proliferate and form tumors, suggesting the senescence response is antagonistically pleiotropic. We show that premalignant mammary epithe...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.01635
更新日期：2005-02-01 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：:The protozoan parasite Giardia intestinalis (also known as Giardia lamblia) is a major waterborne pathogen. During its life cycle, Giardia alternates between the actively growing trophozoite, which has two diploid nuclei with low levels of allelic heterozygosity, and the infectious cyst, which has four nuclei and a to...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.103879
更新日期：2012-05-15 00:00:00
abstract：:Phosphatidylinositol phosphates are important regulators of processes such as the cytoskeleton organization, membrane trafficking and gene transcription, which are all crucial for polarized cell growth. In particular, phosphatidylinositol 4,5-bisphosphate [PtdIns(4,5)P2] has essential roles in polarized growth as well...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.122606
更新日期：2013-08-15 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：:Rickettsia conorii, the causative agent of Mediterranean spotted fever, is able to attach to and invade a variety of cell types both in vitro and in vivo. Although previous studies show that entry of R. conorii into non-phagocytic cells relies on actin polymerization, little else is known about the molecular details g...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.01382
更新日期：2004-10-01 00:00:00
abstract：:The specific phosphatase inhibitor okadaic acid (OA) induced fragmentation of the Golgi apparatus in interphase HeLa cells. Immunoelectron microscopy for galactosyltransferase identified a major Golgi fragment composed of a cluster of vesicles and tubules that was morphologically indistinguishable from the 'Golgi clus...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1991-12-01 00:00:00
abstract：:Wound healing crucially relies on the mechanical activity of fibroblasts responding to TGFβ1 and to forces transmitted across focal adhesions. Integrin-linked kinase (ILK) is a central adapter recruited to integrin β1 tails in focal adhesions mediating the communication between cells and extracellular matrix. Here, we...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.063024
更新日期：2010-11-15 00:00:00
abstract：:Na+/H+ exchangers (NHEs) are transporters that exchange sodium and proton ions across the plasma membrane at the expense of their chemical gradient. In higher eukaryotes these transporters exist as multiple specialized isoforms. For example, NHE1, the ubiquitously expressed form is a major pH-regulating system whereas...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1996-05-01 00:00:00
abstract：:The telomeric repeat binding factor 2 (TRF2) specifically recognizes TTAGGG tandem repeats at chromosomal ends. Unexpectedly immunofluorescence studies revealed a prominent nucleolar localization of TRF2 in human cells, which appeared as discrete dots with sizes similar to those present in the nucleoplasm. The TRF2 do...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.01249
更新日期：2004-08-01 00:00:00
abstract：:Earlier studies have established that the average speed of a replication fork is two to three times slower in early S-phase than in late S-phase and that the intracellular 2'-deoxyribonucleoside 5'-triphosphate pools grow during S-phase. In this study, the effect of the exogenous 2'-deoxyribonucleoside 5'-triphosphate...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：2001-02-01 00:00:00
