Mitochondrial transcription factor A induction by redox activation of nuclear respiratory factor 1.
AuthorsPiantadosi CA,Suliman HB
JournalThe Journal of biological chemistry
PubMed ID16230352
Identification of the hyaluronan receptor for endocytosis (HARE).
AuthorsZhou B, Weigel JA, Fauss L, Weigel PH
JournalJ Biol Chem
PubMed ID10952975
'Rat liver sinusoidal endothelial cells (LECs) express two hyaluronan (HA) receptors, of 175 and 300 kDa, responsible for the endocytic clearance of HA. We have characterized eight monoclonal antibodies (mAbs) raised against the 175-kDa HA receptor partially purified from rat LECs. These mAbs also cross-react with the 300-kDa HA receptor. ... More
Identification of 12-lipoxygenase interaction with cellular proteins by yeast two-hybrid screening.
AuthorsTang K, Finley RL, Nie D, Honn KV
JournalBiochemistry
PubMed ID10727209
'The platelet isoform of 12-lipoxygenase (12-LOX) is expressed in a variety of human tumors. 12-LOX metabolizes arachidonic acid to 12(S)-hydroxyeicosateraenoic acid (12(S)-HETE), which induces a number of cellular responses associated with tumor progression and metastasis. Little is known about 12-LOX regulation and no direct regulators of 12-LOX activity have been ... More
Retrograde transport from the pre-Golgi intermediate compartment and the Golgi complex is affected by the vacuolar H+-ATPase inhibitor bafilomycin A1.
AuthorsPalokangas H, Ying M, Väänänen K, Saraste J
JournalMol Biol Cell
PubMed ID9843588
'The effect of the vacuolar H+-ATPase inhibitor bafilomycin A1 (Baf A1) on the localization of pre-Golgi intermediate compartment (IC) and Golgi marker proteins was used to study the role of acidification in the function of early secretory compartments. Baf A1 inhibited both brefeldin A- and nocodazole-induced retrograde transport of Golgi ... More
Activation of the MAPK signal cascade by the neural cell adhesion molecule L1 requires L1 internalization.
AuthorsSchaefer AW, Kamiguchi H, Wong EV, Beach CM, Landreth G, Lemmon V
JournalJ Biol Chem
PubMed ID10608864
'L1-mediated axon growth involves intracellular signaling, but the precise mechanisms involved are not yet clear. We report a role for the mitogen-activated protein kinase (MAPK) cascade in L1 signaling. L1 physically associates with the MAPK cascade components Raf-1, ERK2, and the previously identified p90(rsk) in brain. In vitro, ERK2 can ... More
Cloning and functional identification of a neuronal glutamine transporter.
AuthorsVaroqui H, Zhu H, Yao D, Ming H, Erickson JD
JournalJ Biol Chem
PubMed ID10660562
'Glutamine is the preferred precursor for the neurotransmitter pool of glutamate, the major excitatory transmitter in the mammalian central nervous system. We have isolated a complementary DNA clone (designated GlnT) encoding a plasma membrane glutamine transporter from glutamatergic neurons in culture, and its properties have been examined using the T7 ... More
Hu protein as an early marker of neuronal phenotypic differentiation by subependymal zone cells of the adult songbird forebrain.
AuthorsBarami K, Iversen K, Furneaux H, Goldman SA
JournalJ Neurobiol
PubMed ID8586967
'The avian forebrain exhibits neurogenesis in adulthood, with neuronal production from ependymal/subependymal zone (SZ) precursor cells. To follow the commitment of newborn cells to neuronal lineage, we used their expression of the Hu family of neuronal RNA-binding proteins to identify them before their migration from the SZ. Adult canaries were ... More
Simultaneous visualization of G- and F-actin in endothelial cells.
AuthorsHaugland RP, You W, Paragas VB, Wells KS, DuBose DA
JournalJ Histochem Cytochem
PubMed ID8308251
'We developed site-specific fluorescent probes that permit simultaneous microscopic observation of G- and F-actin in bovine endothelial cells. G-actin distribution was visualized with fluorescein-deoxyribonuclease I (DNAse I). F-actin was labeled with phalloidin conjugated to the new long-wavelength fluorophore BODIPY 581/591 (581-nm excitation, 591-nm emission), which is spectrally similar to Texas ... More
Immunological evidence for methylglyoxal-derived modifications in vivo. Determination of antigenic epitopes.
AuthorsShamsi FA, Partal A, Sady C, Glomb MA, Nagaraj RH
JournalJ Biol Chem
PubMed ID9506998
'The Maillard reaction, a non-enzymatic reaction of ketones and aldehydes with amino groups of proteins, contributes to the aging of proteins and to complications associated with diabetes. Methylglyoxal (MG) is a 2-oxoaldehyde derived from glycolytic intermediates and produced during the Maillard reaction. We reported previously the formation of a lysine-lysine ... More
Identification of a novel domain in two mammalian inositol-polyphosphate 5-phosphatases that mediates membrane ruffle localization. The inositol 5-phosphatase skip localizes to the endoplasmic reticulum and translocates to membrane ruffles following epidermal growth factor stimulation.
AuthorsGurung R, Tan A, Ooms LM, McGrath MJ, Huysmans RD, Munday AD, Prescott M, Whisstock JC, Mitchell CA
JournalJ Biol Chem
PubMed ID12536145
'SKIP (skeletal muscle and kidney enriched inositol phosphatase) is a recently identified phosphatidylinositol 3,4,5-trisphosphate- and phosphatidylinositol 4,5-bisphosphate-specific 5-phosphatase. In this study, we investigated the intracellular localization of SKIP. Indirect immunofluorescence and subcellular fractionation showed that, in serum-starved cells, both endogenous and recombinant SKIP colocalized with markers of the endoplasmic reticulum ... More
Microtubule-associated movement of mitochondria and small particles in Acanthamoeba castellanii.
AuthorsBaumann O, Murphy DB
JournalCell Motil Cytoskeleton
PubMed ID8608609
'Using video-enhanced differential interference microscopy and digital image processing, we have observed organelle motility in Acanthamoeba castellanii. In amoebae taken from cultures in rapid growth phase, mitochondria and small particles moved over distances of several microns and at an average velocity of approximately 2 microns/s. Mitochondrial motility was verified by ... More
Single-cell analyses reveal two defects in peptide-specific activation of naive T cells from aged mice.
AuthorsGarcia GG, Miller RA
JournalJ Immunol
PubMed ID11207267
'Confocal fluorescent microscopy was used to study redistribution of membrane-associated proteins in naive T cells from young and old mice from a transgenic stock whose T cells express a TCR specific for a peptide derived from pigeon cytochrome C. About 50% of the T cells from young mice that formed ... More
Visualization of replication initiation and elongation in Drosophila.
AuthorsClaycomb JM, MacAlpine DM, Evans JG, Bell SP, Orr-Weaver TL
JournalJ Cell Biol
PubMed ID12403810
'Chorion gene amplification in the ovaries of Drosophila melanogaster is a powerful system for the study of metazoan DNA replication in vivo. Using a combination of high-resolution confocal and deconvolution microscopy and quantitative realtime PCR, we found that initiation and elongation occur during separate developmental stages, thus permitting analysis of ... More
Abnormal migration phenotype of mitogen-activated protein kinase-activated protein kinase 2-/- neutrophils in Zigmond chambers containing formyl-methionyl-leucyl-phenylalanine gradients.
AuthorsHannigan MO, Zhan L, Ai Y, Kotlyarov A, Gaestel M, Huang CK
JournalJ Immunol
PubMed ID11564814
'Time-lapsed video microscopy and confocal imaging were used to study the migration of wild-type (WT) and mitogen-activated protein kinase-activated protein kinase 2 (MK2-/-) mouse neutrophils in Zigmond chambers containing fMLP gradients. Confocal images of polarized WT neutrophils showed an intracellular gradient of phospho-MK2 from the anterior to the posterior region ... More
Ubiquitous GFP expression in transgenic chickens using a lentiviral vector.
AuthorsChapman SC, Lawson A, Macarthur WC, Wiese RJ, Loechel RH, Burgos-Trinidad M, Wakefield JK, Ramabhadran R, Mauch TJ, Schoenwolf GC
JournalDevelopment
PubMed ID15673573
'We report the first ubiquitous green fluorescent protein expression in chicks using a lentiviral vector approach, with eGFP under the control of the phosphoglycerol kinase promoter. Several demonstrations of germline transmission in chicks have been reported previously, using markers that produce tissue-specific, but not ubiquitous, expression. Using embryos sired by ... More
Sarcolipin regulates the activity of SERCA1, the fast-twitch skeletal muscle sarcoplasmic reticulum Ca2+-ATPase.
AuthorsOdermatt A, Becker S, Khanna VK, Kurzydlowski K, Leisner E, Pette D, MacLennan DH
JournalJ Biol Chem
PubMed ID9575189
'The 31-amino acid proteolipid, sarcolipin (SLN), is associated with the fast-twitch skeletal muscle sarcoplasmic reticulum Ca2+-ATPase (SERCA1). Constructs of human and rabbit SLN and of rabbit SLN with the FLAG epitope at its N terminus (NF-SLN) or its C terminus (SLN-FC) were coexpressed with SERCA1 in HEK-293 T-cells. Immunohistochemistry was ... More
Characterization of dominant negative arrestins that inhibit beta2-adrenergic receptor internalization by distinct mechanisms.
AuthorsOrsini MJ, Benovic JL
JournalJ Biol Chem
PubMed ID9852134
'Arrestins have been shown to act as adaptor proteins that mediate the interaction of G protein-coupled receptors with the endocytic machinery. In this study, the role of arrestin-3 in receptor internalization was investigated by constructing different arrestin-3 minigenes that could potentially act as dominant negative inhibitors of arrestin function. Expression ... More
MAUB is a new mucin antigen associated with bladder cancer.
AuthorsBergeron A, Champetier S, LaRue H, Fradet Y
JournalJ Biol Chem
PubMed ID8636121
'The M344 tumor-associated antigen, expressed in 70% of superficial bladder tumors, is a sialylated carbohydrate present on a high molecular mass thiol-reducible secreted mucin, which we named MAUB for mucin antigen of the urinary bladder. Herein we studied the relationship between MAUB and other known mucins in the MGH-U3 bladder ... More
Lipid rafts in the maintenance of synapses, dendritic spines, and surface AMPA receptor stability.
AuthorsHering H, Lin CC, Sheng M
JournalJ Neurosci
PubMed ID12716933
'Cholesterol/sphingolipid microdomains (lipid rafts) in the membrane are involved in protein trafficking, formation of signaling complexes, and regulation of actin cytoskeleton. Here, we show that lipid rafts exist abundantly in dendrites of cultured hippocampal neurons, in which they are associated with several postsynaptic proteins including surface AMPA receptors. Depletion of ... More
An analysis of changes in the expression of cyclins A and B1 by the cell array system during the cell cycle: comparison between cell synchronization methods.
AuthorsTakita M, Furuya T, Sugita T, Kawauchi S, Oga A, Hirano T, Tsunoda S, Sasaki K
JournalCytometry A
PubMed ID12938185
'BACKGROUND: A novel high-throughput analysis, cell array system, was developed for an extensive study of the expression of genes and/or the degradation of gene products at the cellular level. To exemplify the usefulness of this system, we showed the changes in the expression level of cyclin A and B1 during ... More
Involvement of raft-like plasma membrane domains of Entamoeba histolytica in pinocytosis and adhesion.
AuthorsLaughlin RC, McGugan GC, Powell RR, Welter BH, Temesvari LA
JournalInfect Immun
PubMed ID15322032
'Lipid rafts are highly ordered, cholesterol-rich, and detergent-resistant microdomains found in the plasma membrane of many eukaryotic cells. These domains play important roles in endocytosis, secretion, and adhesion in a variety of cell types. The parasitic protozoan Entamoeba histolytica, the causative agent of amoebic dysentery, was determined to have raft-like ... More
Direct observation of endocytosis of gastrin releasing peptide and its receptor.
Authors Grady E F; Slice L W; Brant W O; Walsh J H; Payan D G; Bunnett N W;
JournalJ Biol Chem
PubMed ID7876231
'Endocytosis of the gastrin releasing peptide receptor (GRP-R) may regulate cellular responses to GRP. We observed endocytosis in transfected epithelial cells by confocal microscopy using cyanine 3-GRP (cyanine 3.18-labeled gastrin releasing peptide) and GRP-R antibodies. At 4 degrees C, cy3-GRP and GRP-R were confined to the plasma membrane. After 5 ... More
Inositol 1,4,5-trisphosphate and ryanodine receptor distributions and patterns of acetylcholine- and caffeine-induced calcium release in cultured mouse hippocampal neurons.
AuthorsSeymour-Laurent KJ, Barish ME
JournalJ Neurosci
PubMed ID7722617
'The distributions of inositol 1,4,5-trisphosphate and ryanodine receptors (InsP3R and RyR) and the patterns of increase in intracellular calcium ion concentration ([Ca2+]i) elicited by their activation were compared in cultured hippocampal neurons. InsP3R and RyR were labeled using specific antibodies and formed small aggregations in the somata and dendrites of ... More
Comparison of anti-fading agents used in fluorescence microscopy: image analysis and laser confocal microscopy study.
AuthorsLongin A, Souchier C, Ffrench M, Bryon PA
JournalJ Histochem Cytochem
PubMed ID8245431
'To ascertain the ability of commercial and home-made anti-fading media to reduce the decrease of fluorescein isothiocyanate (FITC) fluorescence, we studied the bleaching characteristics of FITC-stained Reh 6 cells mounted in buffered glycerol and in anti-fading media. We measured the intensity of fluorescence over time with a confocal laser scanning ... More
Interaction of human breast fibroblasts with collagen I increases secretion of procathepsin B.
Authors Koblinski Jennifer E; Dosescu Julie; Sameni Mansoureh; Moin Kamiar; Clark Katherine; Sloane Bonnie F;
JournalJ Biol Chem
PubMed ID12072442
'Interactions of stromal and tumor cells with the extracellular matrix may regulate expression of proteases including the lysosomal proteases cathepsins B and D. In the present study, we determined whether the expression of these two proteases in human breast fibroblasts was modulated by interactions with the extracellular matrix component, collagen ... More
Effect of cytotoxic necrotizing factor-1 on actin cytoskeleton in human monocytes: role in the regulation of integrin-dependent phagocytosis.
'Cytotoxic necrotizing factor-1 (CNF1) is isolated from pathogenic strains of Escherichia coli and catalyzes the activation of Rho GTPases by the deamidation of a glutamine residue. This toxin induces stress fiber formation, cell spreading, and membrane folding and promotes phagocytosis competence in epithelial cells. We show that CNF1 induces morphologic ... More
Imaging proteolysis by living human glioma cells.
AuthorsSameni M, Dosescu J, Sloane BF
JournalBiol Chem
PubMed ID11517931
'Degradation of basement membrane is an essential step for tumor invasion. In order to study degradation in real time as well as localize the site of proteolysis, we have established an assay with living human cancer cells in which we image cleavage of quenched-fluorescent basement membrane type IV collagen (DQ-collagen ... More
Liver fatty acid-binding protein colocalizes with peroxisome proliferator activated receptor alpha and enhances ligand distribution to nuclei of living cells.
AuthorsHuang H, Starodub O, McIntosh A, Atshaves BP, Woldegiorgis G, Kier AB, Schroeder F
JournalBiochemistry
PubMed ID14992586
'Although it is hypothesized that long-chain fatty acyl CoAs (LCFA-CoAs) and long-chain fatty acids (LCFAs) regulate transcription in the nucleus, little is known regarding factors that determine the distribution of these ligands to nuclei of living cells. Immunofluorescence colocalization showed that liver fatty acid-binding protein (L-FABP; binds LCFA-CoA as well ... More
Visualization of agonist-induced sequestration and down-regulation of a green fluorescent protein-tagged beta2-adrenergic receptor.
AuthorsKallal L, Gagnon AW, Penn RB, Benovic JL
JournalJ Biol Chem
PubMed ID9417083
'To date, the visualization of beta2-adrenergic receptor (beta2AR) trafficking has been largely limited to immunocytochemical analyses of acute internalization events of epitope-tagged receptors in various transfection systems. The development of a beta2AR conjugated with green fluorescent protein (beta2AR-GFP) provides the opportunity for a more extensive optical analysis of beta2AR sequestration, ... More
Electric field-directed fibroblast locomotion involves cell surface molecular reorganization and is calcium independent.
AuthorsBrown MJ, Loew LM
JournalJ Cell Biol
PubMed ID7929557
'Directional cellular locomotion is thought to involve localized intracellular calcium changes and the lateral transport of cell surface molecules. We have examined the roles of both calcium and cell surface glycoprotein redistribution in the directional migration of two murine fibroblastic cell lines, NIH 3T3 and SV101. These cell types exhibit ... More
Activation-induced deaminase cloning, localization, and protein extraction from young VH-mutant rabbit appendix.
'Studies in mouse, human, and chicken suggest that activation-induced deaminase (AID) is involved in three known processes leading to antibody diversification: somatic hypermutation, gene conversion, and class-switch recombination. Developing rabbit appendix provides a particularly good site for studying all three of these B cell maturation events. We report here successful ... More
Phosphorylation and subcellular redistribution of pleckstrin in human neutrophils.
AuthorsBrumell JH, Craig KL, Ferguson D, Tyers M, Grinstein S
JournalJ Immunol
PubMed ID9144502
'Pleckstrin, originally described as a major substrate of protein kinase C (PKC) in platelets, was found to be highly expressed in human neutrophils (intracellular concentration, approximately 15 microM). As PKC isoforms play an important role in mediating neutrophil antimicrobial responses, we studied the regulation of pleckstrin phosphorylation in response to ... More
NO inhibits stretch-induced MAPK activity by cytoskeletal disruption.
AuthorsIngram AJ, James L, Cai L, Thai K, Ly H, Scholey JW
JournalJ Biol Chem
PubMed ID10984494
'Mesangial cells (MC) grown on extracellular matrix protein-coated plates and exposed to cyclic strain/relaxation proliferate and produce extracellular matrix protein, providing an in vitro model of signaling in stretched MC. Intracellular transduction of mechanical strain involves mitogen-activated protein kinases, and we have shown that p42/44 mitogen-activated protein kinase (extracellular signal-regulated ... More
Peroxisome senescence in human fibroblasts.
AuthorsLegakis JE, Koepke JI, Jedeszko C, Barlaskar F, Terlecky LJ, Edwards HJ, Walton PA, Terlecky SR
JournalMol Biol Cell
PubMed ID12475949
'The molecular mechanisms of peroxisome biogenesis have begun to emerge; in contrast, relatively little is known about how the organelle functions as cells age. In this report, we characterize age-related changes in peroxisomes of human cells. We show that aging compromises peroxisomal targeting signal 1 (PTS1) protein import, affecting in ... More
Comparison of methods for monitoring bacterial transport in the subsurface.
'The purpose of this study was to compare in a laboratory experiment, a suite of methods developed to track viable bacteria during field transport experiments. The criteria for development and selection of these methods included: (1) the ability to track bacteria within the environment from which they were isolated; (2) ... More
Evaluation of cell morphology by video recording and computer-assisted image analysis.
AuthorsBerezin V, Skladchikova G, Bock E
JournalCytometry
PubMed ID9012377
'The aim of this study was to evaluate the effects of various cell culture conditions on cell morphology. Cell morphology was estimated by means of video recording and computer-assisted image analysis. Cell contours from the stored images of either live cells or fixed and stained cells were determined automatically, and ... More
Antifading agents for confocal fluorescence microscopy.
AuthorsBerrios M, Conlon KA, Colflesh DE
JournalMethods Enzymol
PubMed ID10506967
Fluorescence microscopy techniques for the study of G protein-coupled receptor trafficking.
AuthorsKallal L, Benovic JL
JournalMethods Enzymol
PubMed ID11665588
Spectra and lifetimes of fluorescence resonance energy transfer fluorophores under two-photon excitation.
AuthorsAshman R, Crimeen-Irwin B, Ludford-Menting M, Russell S, Gu M
JournalScanning
PubMed ID12866644
We show two-photon spectra and lifetimes acquired using conventional confocal microscopes equipped with an ultra-short pulsed laser and a time-gated intensified charge coupled device. We report on the two-photon spectra and lifetimes of Alexa350, enhanced green fluorescent protein (EGFP), EGFP-CD46, and Cy3 labelled antibodies. Cellular and extracellular EGFP two-photon spectra ... More
Anti-fading agents for confocal immunofluorescence: colocalization of nuclear polypeptides.
AuthorsBerrios M, Colflesh DE
JournalBiotech Histochem
PubMed ID7779989
We evaluated the performance of four anti-fading agents during acquisition of multiple optical sections near the widest diameter of Drosophila accessory gland nuclei using indirect immunofluorescence and confocal laser scanning microscopy. Two commercially available agents, Vectashield and SlowFade showed anti-fading properties that alleviated fluorochrome fading associated with the acquisition of ... More
Correlative microscopy using FluoroNanogold on ultrathin cryosections. Proof of principle.
AuthorsTakizawa T, Suzuki K, Robinson JM
JournalJ Histochem Cytochem
PubMed ID9742065
We demonstrate a fluorescent ultrasmall immunogold probe, FluoroNanogold (FNG), to be a versatile reporter system for immunocytochemical labeling of ultrathin cryosections. FNG-labeled molecules in the same ultrathin cryosections can be resolved by two imaging techniques (i.e., fluorescence and electron microscopy). Lactoferrin, a marker protein for the specific granules in human ... More
An unfolded putative transmembrane polypeptide, which can lead to endoplasmic reticulum stress, is a substrate of Parkin.
AuthorsImai Y, Soda M, Inoue H, Hattori N, Mizuno Y, Takahashi R
JournalCell
PubMed ID11439185
A putative G protein-coupled transmembrane polypeptide, named Pael receptor, was identified as an interacting protein with Parkin, a gene product responsible for autosomal recessive juvenile Parkinsonism (AR-JP). When overexpressed in cells, this receptor tends to become unfolded, insoluble, and ubiquitinated in vivo. The insoluble Pael receptor leads to unfolded protein-induced ... More
Synaptic regulation of glial protein expression in vivo.
We investigated signaling between individual nerve terminals and perisynaptic Schwann cells, the teloglial cells that cover neuromuscular junctions. When deprived of neuronal activity in vivo, either by motor nerve transection or tetrodotoxin injection, perisynaptic Schwann cells rapidly up-regulated glial fibrillary acidic protein. Addition of transcription or translation inhibitors to excised ... More
Two distinct pathways remove mammalian cohesin from chromosome arms in prophase and from centromeres in anaphase.
AuthorsWaizenegger IC, Hauf S, Meinke A, Peters JM
JournalCell
PubMed ID11081627
In yeast, anaphase depends on cohesin cleavage. How anaphase is controlled in vertebrates is unknown because their cohesins dissociate from chromosomes before anaphase. We show that residual amounts of the cohesin SCC1 remain associated with human centromeres until the onset of anaphase when a similarly small amount of SCC1 is ... More
Contactin orchestrates assembly of the septate-like junctions at the paranode in myelinated peripheral nerve.
AuthorsBoyle ME, Berglund EO, Murai KK, Weber L, Peles E, Ranscht B
JournalNeuron
PubMed ID11395001
Rapid nerve impulse conduction depends on specialized membrane domains in myelinated nerve, the node of Ranvier, the paranode, and the myelinated internodal region. We report that GPI-linked contactin enables the formation of the paranodal septate-like axo-glial junctions in myelinated peripheral nerve. Contactin clusters at the paranodal axolemma during Schwann cell ... More
Tenascin-C suppresses Rho activation.
AuthorsWenk MB, Midwood KS, Schwarzbauer JE
JournalJ Cell Biol
PubMed ID10953015
Cell binding to extracellular matrix (ECM) components changes cytoskeletal organization by the activation of Rho family GTPases. Tenascin-C, a developmentally regulated matrix protein, modulates cellular responses to other matrix proteins, such as fibronectin (FN). Here, we report that tenascin-C markedly altered cell phenotype on a three-dimensional fibrin matrix containing FN, ... More
Regulation of Schizosaccharomyces pombe Wee1 tyrosine kinase.
AuthorsAligue R, Wu L, Russell P
JournalJ Biol Chem
PubMed ID9148953
Wee1 tyrosine kinase regulates mitosis by carrying out the inhibitory tyrosine 15 phosphorylation of Cdc2 M-phase inducing kinase. Schizosaccharomyces pombe Wee1 is a large protein, consisting of a C-terminal catalytic domain of approximately 350 amino acids preceded by a N-terminal domain of approximately 550 residues. The functional properties of the ... More
ATP-dependent regulation of sodium-calcium exchange in Chinese hamster ovary cells transfected with the bovine cardiac sodium-calcium exchanger.
Chinese hamster ovary cells expressing the bovine cardiac Na/Ca exchanger were treated with ouabain to increase [Na+]i and stimulate Ca2+ influx by Na/Ca exchange. Depletion of cellular ATP inhibited 45Ca uptake by 40% or more and reduced the half-maximal Na+ concentration for inhibition of 45Ca uptake from 90 to 55 ... More
Dynamic elastic behavior of alpha-satellite DNA domains visualized in situ in living human cells.
AuthorsShelby RD, Hahn KM, Sullivan KF
JournalJ Cell Biol
PubMed ID8909532
We have constructed a fluorescent alpha-satellite DNA-binding protein to explore the motile and mechanical properties of human centromeres. A fusion protein consisting of human CENP-B coupled to the green fluorescent protein (GFP) of A. victoria specifically targets to centromeres when expressed in human cells. Morphometric analysis revealed that the alpha-satellite ... More
The mammalian Scribble polarity protein regulates epithelial cell adhesion and migration through E-cadherin.
AuthorsQin Y, Capaldo C, Gumbiner BM, Macara IG
JournalJ Cell Biol
PubMed ID16344308
Scribble (Scrib) is a conserved polarity protein required in Drosophila melanogaster for synaptic function, neuroblast differentiation, and epithelial polarization. It is also a tumor suppressor. In rodents, Scrib has been implicated in receptor recycling and planar polarity but not in apical/basal polarity. We now show that knockdown of Scrib disrupts ... More
The role of endocytosis in regulating L1-mediated adhesion.
AuthorsLong KE, Asou H, Snider MD, Lemmon V
JournalJ Biol Chem
PubMed ID11035015
L1 is a neural cell adhesion molecule critical for neural development. Full-length L1 (L1(FL)) contains an alternatively spliced cytoplasmic sequence, RSLE, which is absent in L1 expressed in nonneuronal cells. The RSLE sequence follows a tyrosine, creating an endocytic motif that allows rapid internalization via clathrin-mediated endocytosis. We hypothesized that ... More
Regulation of cyclin D1 by calpain protease.
AuthorsChoi YH, Lee SJ, Nguyen P, Jang JS, Lee J, Wu ML, Takano E, Maki M, Henkart PA, Trepel JB
JournalJ Biol Chem
PubMed ID9353308
Cyclin D1, a critical positive regulator of G1 progression, has been implicated in the pathogenesis of certain cancers. Regulation of cyclin D1 occurs at the transcriptional and posttranscriptional level. Here we present evidence that cyclin D1 levels are regulated at the posttranscriptional level by the Ca2+-activated protease calpain. Serum starvation ... More
Spatial and temporal dynamics of DNA replication sites in mammalian cells.
Fluorescence microscopic analysis of newly replicated DNA has revealed discrete granular sites of replication (RS). The average size and number of replication sites from early to mid S-phase suggest that each RS contains numerous replicons clustered together. We are using fluorescence laser scanning confocal microscopy in conjunction with multidimensional image ... More
The protease-activated receptor-2 upregulates keratinocyte phagocytosis.
AuthorsSharlow ER, Paine CS, Babiarz L, Eisinger M, Shapiro S, Seiberg M
JournalJ Cell Sci
PubMed ID10934047
The protease-activated receptor-2 (PAR-2) belongs to the family of seven transmembrane domain receptors, which are activated by the specific enzymatic cleavage of their extracellular amino termini. Synthetic peptides corresponding to the tethered ligand domain (SLIGRL in mouse, SLIGKV in human) can activate PAR-2 without the need for receptor cleavage. PAR-2 ... More
Delayed retraction of filopodia in gelsolin null mice.
AuthorsLu M, Witke W, Kwiatkowski DJ, Kosik KS
JournalJ Cell Biol
PubMed ID9298983
Growth cones extend dynamic protrusions called filopodia and lamellipodia as exploratory probes that signal the direction of neurite growth. Gelsolin, as an actin filament-severing protein, may serve an important role in the rapid shape changes associated with growth cone structures. In wild-type (wt) hippocampal neurons, antibodies against gelsolin labeled the ... More
Role of clathrin-mediated endocytosis in agonist-induced down-regulation of the beta2-adrenergic receptor.
AuthorsGagnon AW, Kallal L, Benovic JL
JournalJ Biol Chem
PubMed ID9507004
Previous studies have demonstrated that non-visual arrestins function as adaptors in clathrin-mediated endocytosis to promote agonist-induced internalization of the beta2-adrenergic receptor (beta2AR). Here, we characterized the effects of arrestins and other modulators of clathrin-mediated endocytosis on down-regulation of the beta2AR. In COS-1 and HeLa cells, non-visual arrestins promote agonist-induced internalization ... More
Evidence that dynamin-2 functions as a signal-transducing GTPase.
AuthorsFish KN, Schmid SL, Damke H
JournalJ Cell Biol
PubMed ID10893263
The role of dynamin GTPases in the regulation of receptor-mediated endocytosis is well established. Here, we present new evidence that the ubiquitously expressed isoform dynamin-2 (dyn2) can also function in a signal transduction pathway(s). A </=5-fold increase of dyn2 relative to endogenous levels activates the transcription factor p53 and induces ... More
Caveolin-1 inhibits epidermal growth factor-stimulated lamellipod extension and cell migration in metastatic mammary adenocarcinoma cells (MTLn3). Transformation suppressor effects of adenovirus-mediated gene delivery of caveolin-1.
Caveolin-1 is a principal component of caveolae membranes that may function as a transformation suppressor. For example, the human caveolin-1 gene is localized to a suspected tumor suppressor locus (D7S522; 7q31.1) that is deleted in human cancers, including mammary carcinomas. However, little is known about the role of caveolins in ... More
Arabidopsis eIF3e (INT-6) associates with both eIF3c and the COP9 signalosome subunit CSN7.
AuthorsYahalom A, Kim TH, Winter E, Karniol B, von Arnim AG, Chamovitz DA
JournalJ Biol Chem
PubMed ID11029466
The Arabidopsis COP9 signalosome is a multisubunit repressor of photomorphogenesis that is conserved among eukaryotes. This complex may have a general role in development. As a step in dissecting the biochemical mode of action of the COP9 signalosome, we determined the sequence of proteins that copurify with this complex. Here ... More
Phagocytic and macropinocytic activity in MARCKS-deficient macrophages and fibroblasts.
AuthorsCarballo E, Pitterle DM, Stumpo DJ, Sperling RT, Blackshear PJ
JournalAm J Physiol
PubMed ID10409119
Macrophages express high levels of the myristoylated, alanine-rich, C kinase substrate (MARCKS), an actin cross-linking protein. To investigate a possible role of MARCKS in macrophage function, fetal liver-derived macrophages were generated from wild-type and MARCKS knockout mouse embryos. No differences between the wild-type and MARCKS-deficient macrophages with respect to morphology ... More
The PTPmu protein-tyrosine phosphatase binds and recruits the scaffolding protein RACK1 to cell-cell contacts.
AuthorsMourton T, Hellberg CB, Burden-Gulley SM, Hinman J, Rhee A, Brady-Kalnay SM
JournalJ Biol Chem
PubMed ID11278757
PTPmu, an Ig superfamily receptor protein-tyrosine phosphatase, promotes cell-cell adhesion and interacts with the cadherin-catenin complex. The signaling pathway downstream of PTPmu is unknown; therefore, we used a yeast two-hybrid screen to identify additional PTPmu interacting proteins. The membrane-proximal catalytic domain of PTPmu was used as bait. Sequencing of two ... More
Rabphilin localizes with the cell actin cytoskeleton and stimulates association of granules with F-actin cross-linked by {alpha}-actinin.
In endocrine cell, granules accumulate within an F-actin-rich region below the plasma membrane. The mechanisms involved in this process are largely unknown. Rabphilin is a cytosolic protein that is expressed in neurons and neuroendocrine cells and binds with high affinity to members of the Rab3 family of GTPases localized to ... More
Integral membrane proteins of the nuclear envelope are dispersed throughout the endoplasmic reticulum during mitosis.
AuthorsYang L, Guan T, Gerace L
JournalJ Cell Biol
PubMed ID9182656
We have analyzed the fate of several integral membrane proteins of the nuclear envelope during mitosis in cultured mammalian cells to determine whether nuclear membrane proteins are present in a vesicle population distinct from bulk ER membranes after mitotic nuclear envelope disassembly or are dispersed throughout the ER. Using immunofluorescence ... More
Accelerated phagocytosis of amyloid-beta by mouse and human microglia overexpressing the macrophage colony-stimulating factor receptor.
AuthorsMitrasinovic OM, Murphy GM Jr.
JournalJ Biol Chem
PubMed ID12032144
Microglia surrounding A beta plaques in Alzheimer's disease and in the APPV717F transgenic mouse model of Alzheimer's disease have enhanced immunoreactivity for the macrophage colony-stimulating factor receptor (M-CSFR), encoded by the proto-oncogene c-fms. Increased expression of M-CSFR on cultured microglia results in proliferation and release of pro-inflammatory cytokines and expression ... More
Keratocytes pull with similar forces on their dorsal and ventral surfaces.
AuthorsGalbraith CG, Sheetz MP
JournalJ Cell Biol
PubMed ID10601343
As cells move forward, they pull rearward against extracellular matrices (ECMs), exerting traction forces. However, no rearward forces have been seen in the fish keratocyte. To address this discrepancy, we have measured the propulsive forces generated by the keratocyte lamella on both the ventral and the dorsal surfaces. On the ... More
Serum from patients with type 2 diabetes with neuropathy induces complement-independent, calcium-dependent apoptosis in cultured neuronal cells.
AuthorsSrinivasan S, Stevens MJ, Sheng H, Hall KE, Wiley JW
JournalJ Clin Invest
PubMed ID9769338
We hypothesized that sera from type 2 diabetic patients with neuropathy contains an autoimmune immunoglobulin that promotes complement-independent, calcium-dependent apoptosis in neuronal cell lines. Neuronal cells were cultured in the presence of complement-inactivated sera obtained from patients with type 2 diabetes with and without neuropathy and healthy adult control patients. ... More
A role for tissue factor in cell adhesion and migration mediated by interaction with actin-binding protein 280.
AuthorsOtt I, Fischer EG, Miyagi Y, Mueller BM, Ruf W
JournalJ Cell Biol
PubMed ID9490735
Tissue factor (TF), the protease receptor initiating the coagulation system, functions in vascular development, angiogenesis, and tumor cell metastasis by poorly defined molecular mechanisms. We demonstrate that immobilized ligands for TF specifically support cell adhesion, migration, spreading, and intracellular signaling, which are not inhibited by RGD peptides. Two-hybrid screening identified ... More
Intracellular CD22 rapidly moves to the cell surface in a tyrosine kinase-dependent manner following antigen receptor stimulation.
CD22 is a key accessory molecule for Ag receptor signaling in B cells that becomes tyrosine phosphorylated in the signaling process. CD22 associates with sIg and strongly amplifies sIg-induced signals. During B cell development, CD22 is initially expressed intracellularly, with surface expression appearing with IgD expression. We used confocal laser-scanning ... More
Analysis by fluorescence microscopy of the development of compartment-specific gene expression during sporulation of Bacillus subtilis.
AuthorsBylund JE, Zhang L, Haines MA, Higgins ML, Piggot PJ
JournalJ Bacteriol
PubMed ID8188591
The use of a fluorogenic substrate, 5-octanoylaminofluorescein-di-beta-D-galactopyranoside, for beta-galactosidase has made it possible to visualize enzyme activity in individual cells of sporulating populations of Bacillus subtilis by fluorescence microscopy. lacZ fusions to different sporulation-associated genes have been used to investigate the cell compartmentalization of gene expression during sporulation. A strain ... More
Rac1-induced endocytosis is associated with intracellular proteolysis during migration through a three-dimensional matrix.
AuthorsAhram M, Sameni M, Qiu RG, Linebaugh B, Kirn D, Sloane BF
JournalExp Cell Res
PubMed ID11035924
Transfection of Rat1 fibroblasts with an activated form of rac1 (V12rac1) stimulated cell migration in vitro compared to transfection of Rat1 fibroblasts with vector only or with dominant negative rac1 (N17rac1). To investigate the involvement of proteases in this migration, we used a novel confocal assay to evaluate the ability ... More
Localization of L-type Ca2+ channels at perisynaptic glial cells of the frog neuromuscular junction.
AuthorsRobitaille R, Bourque MJ, Vandaele S
JournalJ Neurosci
PubMed ID8613781
The presence of L-type Ca2+ channels at the frog neuromuscular junction (nmj) was studied by monitoring changes in intracellular Ca2+ evoked in presynaptic terminals and perisynaptic Schwann cells (PSCs) and by studying the distribution of Ca2+ channels using a monoclonal antibody directed against the alpha 2/delta subunit of L channels. ... More
Dynamin-mediated internalization of caveolae.
AuthorsHenley JR, Krueger EW, Oswald BJ, McNiven MA
JournalJ Cell Biol
PubMed ID9531550
The dynamins comprise an expanding family of ubiquitously expressed 100-kD GTPases that have been implicated in severing clathrin-coated pits during receptor-mediated endocytosis. Currently, it is unclear whether the different dynamin isoforms perform redundant functions or participate in distinct endocytic processes. To define the function of dynamin II in mammalian epithelial ... More
Imaging proteolysis by living human breast cancer cells.
AuthorsSameni M, Moin K, Sloane BF
JournalNeoplasia
PubMed ID11228542
Malignant progression is accompanied by degradation of extracellular matrix proteins. Here we describe a novel confocal assay in which we can observe proteolysis by living human breast cancer cells (BT20 and BT549) through the use of quenched-fluorescent protein substrates. Degradation thus was imaged, by confocal optical sectioning, as an accumulation ... More
The ELF -97 phosphatase substrate provides a sensitive, photostable method for labelling cytological targets.
AuthorsParagas VB, Kramer JA, Fox C, Haugland RP, Singer VL
JournalJ Microsc
PubMed ID12000550
We compared fluorescent signals obtained with fluorescein conjugates and the ELF-97 (enzyme-labelled fluorescence) phosphatase substrate [2-(5'-chloro-2-phosphoryloxyphenyl)-6-chloro-4(3H)-quinazolinone] in labelling cytological structures requiring high spatial resolution. Enzymatic cleavage of the ELF-97 phosphatase substrate yields an extremely fine precipitate that remains well localized to the site of enzymatic activity. This precipitate fluoresces bright ... More
A 133Cs nuclear magnetic resonance study of endothelial Na(+)-K(+)-ATPase activity: can actin regulate its activity?
AuthorsGruwel ML, Culíc O, Schrader J
JournalBiophys J
PubMed ID9168052
Using (133)Cs+ NMR, we developed a technique to repetitively measure, in vivo, Na(+)-K(+)-ATPase activity in endothelial cells. The measurements were made without the use of an exogenous shift reagent, because of the large chemical shift of 1.36 +/- 0.13 ppm between intra- and extracellular Cs+. Intracellularly we obtained a spin ... More
Heregulin regulates cytoskeletal reorganization and cell migration through the p21-activated kinase-1 via phosphatidylinositol-3 kinase.
The mechanisms through which heregulin (HRG) regulates the activities of breast cancer cells are currently unknown. We demonstrate that HRG stimulation of noninvasive breast cancer cells enhanced the conversion of globular to filamentous actin and the formation of membrane ruffles, stress fibers, filopodia, and lamellipodia and accompanied by increased cell ... More
Identification, sequence, and expression of an invertebrate caveolin gene family from the nematode Caenorhabditis elegans. Implications for the molecular evolution of mammalian caveolin genes.
Caveolae are vesicular organelles that represent an appendage of the plasma membrane. Caveolin, a 21-24-kDa integral membrane protein, is a principal component of caveolae membranes in vivo. Caveolin has been proposed to function as a plasma membrane scaffolding protein to organize and concentrate signaling molecules within caveolae, including heterotrimeric G ... More
The fibronectin extra domain A activates matrix metalloproteinase gene expression by an interleukin-1-dependent mechanism.
AuthorsSaito S, Yamaji N, Yasunaga K, Saito T, Matsumoto S, Katoh M, Kobayashi S, Masuho Y
JournalJ Biol Chem
PubMed ID10521465
The extra domain-A (EDA), present in fibronectin (FN) molecules arising from alternatively spliced transcripts, appears only during specific biological and pathogenic processes. However, its function is poorly understood. To define the physiologic role of this domain in joint connective tissue, the biological effects on rabbit cartilage explants, chondrocytes, and synovial ... More
The apical submembrane cytoskeleton participates in the organization of the apical pole in epithelial cells.
AuthorsSalas PJ, Rodriguez ML, Viciana AL, Vega-Salas DE, Hauri HP
JournalJ Cell Biol
PubMed ID9128248
In a previous publication (Rodriguez, M.L., M. Brignoni, and P.J.I. Salas. 1994. J. Cell Sci. 107: 3145-3151), we described the existence of a terminal web-like structure in nonbrush border cells, which comprises a specifically apical cytokeratin, presumably cytokeratin 19. In the present study we confirmed the apical distribution of cytokeratin ... More
Visualization of melanosome dynamics within wild-type and dilute melanocytes suggests a paradigm for myosin V function In vivo.
AuthorsWu X, Bowers B, Rao K, Wei Q, Hammer JA
JournalJ Cell Biol
PubMed ID9864363
Unlike wild-type mouse melanocytes, where melanosomes are concentrated in dendrites and dendritic tips, melanosomes in dilute (myosin Va-) melanocytes are concentrated in the cell center. Here we sought to define the role that myosin Va plays in melanosome transport and distribution. Actin filaments that comprise a cortical shell running the ... More
Torsin A and its torsion dystonia-associated mutant forms are lumenal glycoproteins that exhibit distinct subcellular localizations.
AuthorsKustedjo K, Bracey MH, Cravatt BF
JournalJ Biol Chem
PubMed ID10871631
Early-onset torsion dystonia is an autosomal dominant hyperkinetic movement disorder that has recently been linked to a 3-base pair deletion in the DYT1 gene. The DYT1 gene encodes a 332-amino acid protein, torsin A, that bears low but significant homology to the Hsp100/Clp family of ATPase chaperones. The deletion in ... More
Localization and regulation of thyrotropin receptors within lipid rafts.
AuthorsLatif R, Ando T, Daniel S, Davies TF
JournalEndocrinology
PubMed ID12960014
The TSH receptor (TSHR) is a prototypic G protein-coupled receptor with a large extracellular domain. We have previously demonstrated homophilic interactions of TSHRs and their existence as constitutive oligomers. However, we have also shown that TSH itself promotes the formation of receptor monomers. We hypothesized, therefore, that TSHR monomers induced ... More
Oligomerized transferrin receptors are selectively retained by a lumenal sorting signal in a long-lived endocytic recycling compartment.
AuthorsMarsh EW, Leopold PL, Jones NL, Maxfield FR
JournalJ Cell Biol
PubMed ID7790351
Cross-linking of surface receptors results in altered receptor trafficking in the endocytic system. To better understand the cellular and molecular mechanisms by which receptor cross-linking affects the intracellular trafficking of both ligand and receptor, we studied the intracellular trafficking of the transferrin receptor (TfR) bound to multivalent-transferrin (Tf10) which was ... More
Regulation of aquaporin-2 trafficking by vasopressin in the renal collecting duct. Roles of ryanodine-sensitive Ca2+ stores and calmodulin.
In the renal collecting duct, vasopressin increases osmotic water permeability (P(f)) by triggering trafficking of aquaporin-2 vesicles to the apical plasma membrane. We investigated the role of vasopressin-induced intracellular Ca(2+) mobilization in this process. In isolated inner medullary collecting ducts (IMCDs), vasopressin (0.1 nm) and 8-(4-chlorophenylthio)-cAMP (0.1 mm) elicited marked ... More
Dependence of both spontaneous and antibody-dependent, granule exocytosis-mediated NK cell cytotoxicity on extracellular signal-regulated kinases.
AuthorsTrotta R, Puorro KA, Paroli M, Azzoni L, Abebe B, Eisenlohr LC, Perussia B
JournalJ Immunol
PubMed ID9862693
Extracellular signal-regulated kinases (ERK, also known as mitogen-activated protein kinases) are serine-threonine kinases transducing signals elicited upon ligand binding to several tyrosine kinase-associated receptors. We have reported that ERK2 phosphorylation and activation follows engagement of the low affinity receptor for the Fc portion of IgG (CD16) on NK cells, and ... More
Structure-function analysis of G protein-coupled receptor kinase-5. Role of the carboxyl terminus in kinase regulation.
AuthorsPronin AN, Carman CV, Benovic JL
JournalJ Biol Chem
PubMed ID9813065
Many G protein-coupled receptors are phosphorylated and regulated by a distinct family of G protein-coupled receptor kinases (GRKs) that specifically target the activated form of the receptor. Recent studies have revealed that the GRKs are also subject to post-translational regulation. For example, GRK5 activity is strongly inhibited by protein kinase ... More
Localization and insulin-regulated relocation of phosphoinositide 5-kinase PIKfyve in 3T3-L1 adipocytes.
AuthorsShisheva A, Rusin B, Ikonomov OC, DeMarco C, Sbrissa D
JournalJ Biol Chem
PubMed ID11112776
The mammalian phosphoinositide kinase PIKfyve catalyzes the synthesis of phosphatidylinositol 5-P and phosphatidylinositol 3,5-P(2), thought essential in cellular functions, including membrane trafficking. To discern the intracellular loci of PIKfyve products' formation, we have examined the localization of PIKfyve protein versus enzymatic activity and a possible acutely regulated redistribution in 3T3-L1 ... More
Calcium-mediated translocation of cytosolic phospholipase A2 to the nuclear envelope and endoplasmic reticulum.
AuthorsSchievella AR, Regier MK, Smith WL, Lin LL
JournalJ Biol Chem
PubMed ID8530515
Cytosolic phospholipase A2 (cPLA2) is activated by a wide variety of stimuli to release arachidonic acid, the precursor of the potent inflammatory mediators prostaglandin and leukotriene. Specifically, cPLA2 releases arachidonic acid in response to agents that increase intracellular Ca2+. In vitro data have suggested that these agents induce a translocation ... More
Development of a vital fluorescent staining method for monitoring bacterial transport in subsurface environments.
Previous bacterial transport studies have utilized fluorophores which have been shown to adversely affect the physiology of stained cells. This research was undertaken to identify alternative fluorescent stains that do not adversely affect the transport or viability of bacteria. Initial work was performed with a groundwater isolate, Comamonas sp. strain ... More
Plasma membrane cholesterol is a key molecule in shear stress-dependent activation of extracellular signal-regulated kinase.
AuthorsPark H, Go YM, St John PL, Maland MC, Lisanti MP, Abrahamson DR, Jo H
JournalJ Biol Chem
PubMed ID9822710
Shear stress, the dragging force generated by fluid flow, differentially activates extracellular signal-regulated kinase (ERK) and c-Jun NH2-terminal kinase (JNK) in bovine aortic endothelial cells (BAEC) (Jo, H., Sipos, K., Go, Y. M., Law, R., Rong, J., and McDonald, J. M. (1997) J. Biol. Chem. 272, 1395-1401). Here, we examine ... More
Regulation of microfilament reorganization and invasiveness of breast cancer cells by kinase dead p21-activated kinase-1.
AuthorsAdam L, Vadlamudi R, Mandal M, Chernoff J, Kumar R
JournalJ Biol Chem
PubMed ID10766836
Stimulation of growth factor signaling has been implicated in the development of invasive phenotype and p21-activated kinase (PAK1) activation in human breast epithelial cancer cells. To further explore the roles of PAK1 in the invasive behavior of breast cancer cells, in the present study we investigated the influence of inhibition ... More
Pericellular pH affects distribution and secretion of cathepsin B in malignant cells.
AuthorsRozhin J, Sameni M, Ziegler G, Sloane BF
JournalCancer Res
PubMed ID7987851
Redistribution of lysosomes to the cell surface and secretion of lysosomal proteases appear to be general phenomena in cells that participate in local proteolysis. In the present study, we have determined whether malignant progression affects the intracellular distribution and secretion of the lysosomal protease cathepsin B in three model systems, ... More