Abstract:
:The vacuolar H(+)-ATPase (V-ATPase) is a multi-subunit enzyme that plays important roles in eukaryotic cells. In Dictyostelium, it is found primarily in membranes of the contractile vacuole complex, where it energizes fluid accumulation by this osmoregulatory organelle and also in membranes of endolysosomes, where it serves to acidify the endosomal lumen. In the present study, a fusion was created between vatM, the gene encoding the 100 kDa transmembrane subunit of the V-ATPase, and the gene encoding Green Fluorescent Protein (GFP). When expressed in Dictyostelium cells, this fusion protein, VatM-GFP, was correctly targeted to contractile vacuole and endolysosomal membranes and was competent to direct assembly of the V-ATPase enzyme complex. Protease treatment of isolated endosomes indicated that the GFP moiety, located on the C-terminus of VatM, was exposed to the cytoplasmic side of the endosomal membrane rather than to the lumenal side. VatM-GFP labeling of the contractile vacuole complex revealed clearly the dynamics of this pleiomorphic vesiculotubular organelle. VatM-GFP labeling of endosomes allowed direct visualization of the trafficking of vacuolar proton pumps in this pathway, which appeared to be entirely independent from the contractile vacuole membrane system. In cells whose endosomes were pre-labeled with TRITC-dextran and then fed yeast particles, VatM-GFP was delivered to newly formed yeast phagosomes with the same time course as TRITC-dextran, consistent with transfer via a direct fusion of endosomes with phagosomes. Several minutes were required before the intensity of the VatM-GFP labeling of new phagosomes reached the level observed in older phagosomes, suggesting that this fusion process was progressive and continuous. VatM-GFP was retrieved from the phagosome membrane prior to exocytosis of the indigestible remnants of the yeast particle. These data suggest that vacuolar proton pumps are recycled by fusion of advanced with newly formed endosomes.
journal_name
J Cell Scijournal_title
Journal of cell scienceauthors
Clarke M,Köhler J,Arana Q,Liu T,Heuser J,Gerisch Gkeywords:
subject
Has Abstractpub_date
2002-07-15 00:00:00pages
2893-905issue
Pt 14eissn
0021-9533issn
1477-9137journal_volume
115pub_type
杂志文章abstract::Little is known of the molecular basis for the diversity of microtubule structure and function found within the eukaryotic flagellum. Antibodies that discriminate between tyrosinated alpha tubulin and post-translationally detyrosinated alpha tubulin were used to localize these complementary tubulin isoforms in flagell...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1998-02-01 00:00:00
abstract::A number of recent studies have highlighted the importance of autophagy and the ubiquitin-proteasome in the pathogenesis of muscle wasting in different types of inherited muscle disorders. Autophagy is crucial for the removal of dysfunctional organelles and protein aggregates, whereas the ubiquitin-proteasome is impor...
journal_title:Journal of cell science
pub_type: 杂志文章,评审
doi:10.1242/jcs.114041
更新日期:2013-12-01 00:00:00
abstract::Dishevelled-3 (Dvl3) is a multivalent scaffold protein that is essential to Wnt signaling during development. Although Dvl-based punctae have been visualized by fluorescence microscopy; the physical nature and dynamic character of the such complexes are enigmatic. We use steric-exclusion chromatography, affinity pull-...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.075275
更新日期:2010-11-01 00:00:00
abstract::Eukaryotic plasma membranes assemble actin filaments within seconds of activation of many receptors, especially during chemotaxis. Here, serum or sphingosine-1-phosphate stimulation of J774 and RAW macrophages released ADP within seconds into the extracellular medium, along with an adenylate kinase activity that conve...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.034207
更新日期:2009-02-15 00:00:00
abstract::We have examined the pattern of expression of four different matrix metalloproteinases (MMPs), collagenase, stromelysin, 92 kD gelatinase, and 72 kD gelatinase, by primary and passaged cultures of rabbit corneal fibroblasts. Primary cultures of this cell type have previously been shown to reproduce the normal tissue r...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1990-10-01 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::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::The small GTP-binding protein Rho rapidly stimulates the formation of focal adhesions and actin stress fibres when microinjected into serum-starved Swiss 3T3 fibroblasts. This response is inhibited by tyrosine kinase inhibitors. Addition of growth factors such as lysophosphatidic acid and bombesin to Swiss 3T3 cells s...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1996-05-01 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::Treatment of cells arrested in the cell cycle at the G1/S-phase boundary with 5 mM caffeine induces premature mitosis, resulting in chromosomal fragmentation and detachment of centromere-kinetochore fragments, which are subsequently attached to the mitotic spindle and segregated in anaphase. Taking advantage of this i...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1993-06-01 00:00:00
abstract::ADP-ribosylation factors (Arfs) and ADP-ribosylation factor-like proteins (Arls) are highly conserved small GTPases that function as main regulators of vesicular trafficking and cytoskeletal reorganization. Arl1, the first identified member of the large Arl family, is an important regulator of Golgi complex structure ...
journal_title:Journal of cell science
pub_type: 杂志文章,评审
doi:10.1242/jcs.201319
更新日期:2017-05-15 00:00:00
abstract::Chloroquine resistance in the human malaria parasite, Plasmodium falciparum, arises from decreased accumulation of the drug in the ;digestive vacuole' of the parasite, an acidic compartment in which chloroquine exerts its primary toxic effect. It has been proposed that changes in the pH of the digestive vacuole might ...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.02795
更新日期:2006-03-15 00:00:00
abstract::We have isolated the human genes encoding the Pyst1 (MKP-3) and Pyst2 (MKP-X) MAP kinase phosphatases. Both genes consist of three exons interrupted by two introns and lack an intron which is conserved in all the other members of this gene family characterised to date. This reinforces the conclusion that Pyst1 and Pys...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1998-11-01 00:00:00
abstract::We describe here the expression during development, tissue distribution and molecular properties of GP90: a major concanavalin A (ConA)-binding glycoprotein present in the neuronal membrane skeleton from chicken brain. GP90 is co-isolated with, and has a similar developmental profile to contactin (previously called GP...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1989-05-01 00:00:00
abstract::To clarify the involvement of actin in the formation of the yeast cell wall, reverting protoplasts of Schizosaccharomyces pombe were used as a simple model system. Actin of reverting protoplasts was labeled with rhodamine-conjugated phalloidin and observed by conventional fluorescence microscopy and laser scanning con...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1989-12-01 00:00:00
abstract::In Saccharomyces cerevisiae, three classes of sphingolipids contain myo-inositol--inositol phosphorylceramide (IPC), mannosylinositol phosphorylceramide (MIPC) and mannosyldiinositol phosphorylceramide [M(IP)(2)C]. No fission yeast equivalent of Ipt1p, the inositolphosphotransferase that synthesizes M(IP)(2)C from MIP...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.059139
更新日期:2010-05-01 00:00:00
abstract::Recently, several 3D images of kinesin-family motor domains interacting with microtubules have been obtained by analysis of electron microscope images of frozen hydrated complexes at much higher resolutions (9-12 A) than in previous reports (15-30 A). The high-resolution maps show a complex interaction interface betwe...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.016931
更新日期:2007-11-15 00:00:00
abstract::In chondrocytes, PTHrP maintains them in a proliferative state and prevents premature hypertrophy. The mechanism by which PTHrP does this is not fully understood. Both Runx2 and Runx3 are required for chondrocyte maturation. We recently demonstrated that cyclin D1 induces Runx2 protein phosphorylation and degradation....
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.040709
更新日期:2009-05-01 00:00:00
abstract::The Cep63-Cep152 complex located at the mother centriole recruits Plk4 to initiate centriole biogenesis. How the complex is targeted to mother centrioles, however, is unclear. In this study, we show that Cep57 and its paralog, Cep57l1, colocalize with Cep63 and Cep152 at the proximal end of mother centrioles in both c...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.241836
更新日期:2020-07-03 00:00:00
abstract::The main neuropathological features of Parkinson's disease are dopaminergic nigrostriatal neuron degeneration, and intraneuronal and intraneuritic proteinaceous inclusions named Lewy bodies and Lewy neurites, respectively, which mainly contain α-synuclein (α-syn, also known as SNCA). The neuronal phosphoprotein synaps...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.157867
更新日期:2015-07-01 00:00:00
abstract::Moving the nucleus to a specific position within the cell is an important event during many cell and developmental processes. Several different molecular mechanisms exist to position nuclei in various cell types. In this Commentary, we review the recent progress made in elucidating mechanisms of nuclear migration in a...
journal_title:Journal of cell science
pub_type: 杂志文章,评审
doi:10.1242/jcs.179788
更新日期:2016-05-15 00:00:00
abstract::Endothelial barrier dysfunction leads to edema and vascular leak, causing high morbidity and mortality. Previously, Abl kinase inhibition has been shown to protect against vascular leak. Using the distinct inhibitory profiles of clinically available Abl kinase inhibitors, we aimed to provide a mechanistic basis for no...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.240077
更新日期:2020-05-14 00:00:00
abstract::Major histocompatibility complex class I (MHC-I) molecules signal infection or transformation by engaging receptors on T lymphocytes. The spatial organization of MHC-I on the plasma membranes is important for this engagement. We and others have shown that MHC-I molecules, like other membrane proteins, are not uniforml...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.187112
更新日期:2016-09-01 00:00:00
abstract::In somatic cells, the heterodimeric Structural Maintenance of Chromosomes (SMC) proteins are involved in chromosome condensation and gene dosage compensation (SMC2 and 4), and sister chromatid cohesion and DNA recombination (SMC1 and 3). We report here evidence for an involvement of mammalian SMC1 and SMC3 proteins in...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:2000-02-01 00:00:00
abstract::Structures retaining many of the morphological features of nuclei may be released by gently lysing human cells in solutions containing non-ionic detergents and high concentrations of salt. These nucleoids contain superhelical DNA. Using a double-labelling procedure we have compared, at different salt concentrations, t...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1978-02-01 00:00:00
abstract::Endothelial cells (ECs) sense shear stress and transduce blood flow information into functional responses that play important roles in vascular homeostasis and pathophysiology. A unique feature of shear-stress-sensing is the involvement of many different types of membrane-bound molecules, including receptors, ion chan...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.119628
更新日期:2013-03-01 00:00:00
abstract::A UV-damaged DNA binding protein (UV-DDB) is the major source of UV-damaged DNA binding activity in mammalian cell extracts. This activity is defective in at least some xeroderma pigmentosum group E (XP-E) patients; microinjection of the UV-DDB protein into their fibroblasts corrects nucleotide excision repair (NER). ...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1997-05-01 00:00:00
abstract::KLP61F in Drosophila and other BimC kinesins are essential for spindle bipolarity across species; loss of BimC function generates high frequencies of monopolar spindles. Concomitant loss of Kar3 kinesin function increases the frequency of bipolar spindles although the underlying mechanism is not known. Recent studies ...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:10.1242/jcs.01334
更新日期:2004-10-01 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::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