'It is uncertain how antiviral lymphocytes are activated in draining lymph nodes, the site where adaptive immune responses are initiated. Here, using intravital microscopy we show that after infection of mice with vaccinia virus (a large DNA virus) or vesicular stomatitis virus (a small RNA virus), virions drained to the ... More
Regulation of neuronal traits by a novel transcriptional complex.
AuthorsBallas N, Battaglioli E, Atouf F, Andres ME, Chenoweth J, Anderson ME, Burger C, Moniwa M, Davie JR, Bowers WJ, Federoff HJ, Rose DW, Rosenfeld MG, Brehm P, Mandel G
JournalNeuron
PubMed ID11516394
'The transcriptional repressor, REST, helps restrict neuronal traits to neurons by blocking their expression in nonneuronal cells. To examine the repercussions of REST expression in neurons, we generated a neuronal cell line that expresses REST conditionally. REST expression inhibited differentiation by nerve growth factor, suppressing both sodium current and neurite ... More
Active nuclear import and export pathways regulate E2F-5 subcellular localization.
'Epidermal keratinocyte differentiation is accompanied by differential regulation of E2F genes, including up-regulation of E2F-5 and its concomitant association with the retinoblastoma family protein p130. This complex appears to play a role in irreversible withdrawal from the cell cycle in differentiating keratinocytes. We now report that keratinocyte differentiation is also ... More
Regulation of endothelial CD73 by adenosine: paracrine pathway for enhanced endothelial barrier function.
AuthorsNarravula S, Lennon PF, Mueller BU, Colgan SP
JournalJ Immunol
PubMed ID11046060
'During episodes of inflammation, multiple cell types release adenine nucleotides in the form of ATP, ADP, 5''-AMP, and adenosine. In particular, following activation, polymorphonuclear leukocytes release larger quantities of 5''-AMP. Extracellular 5''-AMP is metabolized to adenosine by surface-expressed 5''-ectonucleotidase (CD73). Adenosine liberated by this process activates surface adenosine A(2B) receptors, ... More
A role for phosphoinositide 3-kinase in the completion of macropinocytosis and phagocytosis by macrophages.
AuthorsAraki N, Johnson MT, Swanson JA
JournalJ Cell Biol
PubMed ID8947549
'Phosphoinositide 3-kinase (PI 3-kinase) has been implicated in growth factor signal transduction and vesicular membrane traffic. It is thought to mediate the earliest steps leading from ligation of cell surface receptors to increased cell surface ruffling. We show here that inhibitors of PI 3-kinase inhibit endocytosis in macrophages, not by ... More
Identification of distinct luminal domains for macromolecules, erythrocytes, and leukocytes within mammalian capillaries.
AuthorsVink H, Duling BR
JournalCirc Res
PubMed ID8781491
'A thick endothelial surface coat consisting of the glycocalyx and associated plasma proteins has been hypothesized to reduce functional capillary volume available for flowing plasma macromolecules and blood cells. The purpose of this study was to compare anatomic and functional capillary diameters available for macromolecules, RBCs, and WBCs in hamster ... More
The FKBP12-rapamycin-binding domain is required for FKBP12-rapamycin-associated protein kinase activity and G1 progression.
AuthorsVilella-Bach M, Nuzzi P, Fang Y, Chen J
JournalJ Biol Chem
PubMed ID9933627
'The immunosuppressant rapamycin, in complex with its cellular receptor FKBP12, targets the cellular protein FKBP12-rapamycin-associated protein/mammalian target of rapamycin/rapamycin and FKBP12 target 1 (FRAP/mTOR/RAFT1) and inhibits/delays G1 cell cycle progression in mammalian cells. As a member of the novel phosphatidylinositol kinase-related kinase family, FRAP''s kinase activity is essential for its ... More
Transport of cytoskeletal elements in the squid giant axon.
AuthorsTerasaki M, Schmidek A, Galbraith JA, Gallant PE, Reese TS
JournalProc Natl Acad Sci U S A
PubMed ID8524791
'In order to explore how cytoskeletal proteins are moved by axonal transport, we injected fluorescent microtubules and actin filaments as well as exogenous particulates into squid giant axons and observed their movements by confocal microscopy. The squid giant axon is large enough to allow even cytoskeletal assemblies to be injected ... More
Direct measurement of endosomal pH in living cells of the rat yolk sac epithelium by laser confocal microscopy.
AuthorsIchimura T, Hatae T, Ishida T
JournalEur J Cell Biol
PubMed ID9309389
'Endocytosis of dual-fluorescent dextran by epithelial cells was observed in the perfused rat yolk sac using a confocal laser scanning microscope. Endosomal pH was quantified from confocal images using a dual-fluorescence ratiometry technique. Changes in endosomal pH were followed over time up to 32 min with and without Brefeldin A ... More
Splicing promotes rapid and efficient mRNA export in mammalian cells.
AuthorsValencia P, Dias AP, Reed R,
JournalProc Natl Acad Sci U S A
PubMed ID18287003
'The numerous steps in protein gene expression are extensively coupled to one another through complex networks of physical and functional interactions. Indeed, >25 coupled reactions, often reciprocal, have been documented among such steps as transcription, capping, splicing, and polyadenylation. Coupling is usually not essential for gene expression, but instead enhances ... More
Delivery of macromolecules into live cells by simple co-incubation with a peptide.
AuthorsLee YJ, Erazo-Oliveras A, Pellois JP,
JournalChembiochem
PubMed ID20029930
'n this report, we test the hypothesis that optimized cell-penetrating peptides (CPPs) might deliver macromolecules to the cytosol of live cells by simple co-incubation and without the requirement for any type of conjugation, whether covalent or noncovalent. This hypothesis is based on the observation that the binding of TAT and ... More
Arteriolar, capillary, and venular FITC-dextran time-concentration curves and plasma flow velocities.
AuthorsBaker CH, Davis DL, Sutton ET
JournalProc Soc Exp Biol Med
PubMed ID461465
Membrane proximal lysosomes are the major vesicles responsible for calcium-dependent exocytosis in nonsecretory cells.
AuthorsJaiswal JK, Andrews NW, Simon SM
JournalJ Cell Biol
PubMed ID12438417
Similar to its role in secretory cells, calcium triggers exocytosis in nonsecretory cells. This calcium-dependent exocytosis is essential for repair of membrane ruptures. Using total internal reflection fluorescence microscopy, we observed that many organelles implicated in this process, including ER, post-Golgi vesicles, late endosomes, early endosomes, and lysosomes, were within ... More
Activation of lysosomal function during dendritic cell maturation.
AuthorsTrombetta ES, Ebersold M, Garrett W, Pypaert M, Mellman I
JournalScience
PubMed ID12610307
In response to a variety of stimuli, dendritic cells (DCs) transform from immature cells specialized for antigen capture into mature cells specialized for T cell stimulation. During maturation, the DCs acquire an enhanced capacity to form and accumulate peptide-MHC (major histocompatibility complex) class II complexes. Here we show that a ... More
Carboxyfluorescein. A dye for evaluating the corneal endothelial barrier function in vivo.
AuthorsAraie M
JournalExp Eye Res
PubMed ID3699104
The relationship of the cornea-aqueous distribution ratio (r ca) and concentration in vitro was established for fluorescein and carboxyfluorescein. The value of rca for fluorescein was found to fall from 3.20 +/- 0.25 (mean +/- S.D., n V 6) to 1.78 as the concentration of the free fluorescein in the ... More
Mammalian reovirus, a nonfusogenic nonenveloped virus, forms size-selective pores in a model membrane.
AuthorsAgosto MA, Ivanovic T, Nibert ML
JournalProc Natl Acad Sci U S A
PubMed ID17053074
During cell entry, reovirus particles with a diameter of 70-80 nm must penetrate the cellular membrane to access the cytoplasm. The mechanism of penetration, without benefit of membrane fusion, is not well characterized for any such nonenveloped animal virus. Lysis of RBCs is an in vitro assay for the membrane ... More
Movement of the free catalytic subunit of cAMP-dependent protein kinase into and out of the nucleus can be explained by diffusion.
AuthorsHarootunian AT, Adams SR, Wen W, Meinkoth JL, Taylor SS, Tsien RY
JournalMol Biol Cell
PubMed ID8298196
The catalytic (C) subunit of cyclic AMP (cAMP) dependent protein kinase (PKA) has previously been shown to enter and exit the nucleus of cells when intracellular cAMP is raised and lowered, respectively. To determine the mechanism of nuclear translocation, fluorescently labeled C subunit was injected into living REF52 fibroblasts either ... More
Measurement of cerebral capillary perfusion with a fluorescent label.
AuthorsWeiss HR
JournalMicrovasc Res
PubMed ID3141746
The aim of this study was to evaluate methods of labeling the perfused cerebral capillary bed using fluorescein isothiocyanate (FITC)-dextran or FITC-globulin. An alkaline phosphatase stain was used to identify the total capillary bed. All experiments were conducted on anesthetized rats. FITC labels were injected and the rats were sacrificed ... 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
A dominant-negative clathrin mutant differentially affects trafficking of molecules with distinct sorting motifs in the class II major histocompatibility complex (MHC) pathway.
AuthorsLiu SH, Marks MS, Brodsky FM
JournalJ Cell Biol
PubMed ID9490717
The role of clathrin in intracellular sorting was investigated by expression of a dominant-negative mutant form of clathrin, termed the hub fragment. Hub inhibition of clathrin-mediated membrane transport was established by demonstrating a block of transferrin internalization and an alteration in the intracellular distribution of the cation-independent mannose-6-phosphate receptor. Hubs ... More
Aldolase exists in both the fluid and solid phases of cytoplasm.
AuthorsPagliaro L, Taylor DL
JournalJ Cell Biol
PubMed ID2458365
We have prepared a functional fluorescent analogue of the glycolytic enzyme aldolase (rhodamine [Rh]-aldolase), using the succinimidyl ester of carboxytetramethyl-rhodamine. Fluorescence redistribution after photobleaching measurements of the diffusion coefficient of Rh-aldolase in aqueous solutions gave a value of 4.7 x 10(-7) cm2/S, and no immobile fraction. In the presence of ... More
Cellular dimensions affecting the nucleocytoplasmic volume ratio.
AuthorsSwanson JA, Lee M, Knapp PE
JournalJ Cell Biol
PubMed ID1955464
Although it has long been appreciated that larger eukaryotic cells have larger nuclei, little is known about how this size relationship is maintained. Here we describe a method for measuring the aqueous volume ratio of nucleus to cytoplasm, two compartments which are interconnected via the pores in the nuclear envelope. ... More
Exocytosis and endocytosis of small vesicles in PC12 cells studied with TEPIQ (two-photon extracellular polar-tracer imaging-based quantification) analysis.
AuthorsLiu TT, Kishimoto T, Hatakeyama H, Nemoto T, Takahashi N, Kasai H
JournalJ Physiol
PubMed ID16150796
We investigated exocytosis of PC12 cells using two-photon excitation imaging and extracellular polar tracers (TEP imaging) in the lateral membranes not facing the glass-cover slip. Upon photolysis of a caged Ca2+ compound, TEP imaging with FM1-43 (a polar membrane tracer) detected massive exocytosis of vesicles with a time constant of ... More
Redistribution of cytoplasmic components during germinal vesicle breakdown in starfish oocytes.
AuthorsTerasaki M
JournalJ Cell Sci
PubMed ID7527047
The starfish oocyte is relatively clear optically, and its nucleus, termed the germinal vesicle, is large. These characteristics allowed studies by confocal microscopy of germinal vesicle breakdown during maturation in living oocytes. Three fluorescent probes for cytoplasmic components were used: fluorescein 70 kDa dextran, which does not cross the nuclear ... More
Low pH fusion of mouse liver nuclei with liposomes bearing covalently bound lysozyme.
AuthorsArvinte T, Wahl P, Nicolau C
JournalBiochim Biophys Acta
PubMed ID3580361
Lysozyme covalently bound to liposomes induces the fusion of liposomes with isolated mouse liver nuclei. The fusion behavior is very similar to the case of erythrocyte ghosts (Arvinte, T., Hildenbrand, K., Wahl, P. and Nicolau, C. (1986) Proc. Natl. Acad. Sci. USA 83, 962-966). Kinetic studies showed that membrane lipid ... More
Build them up and break them down: Tight junctions of cell lines expressing typical hepatocyte polarity with a varied repertoire of claudins.
Authors
JournalTissue Barriers
PubMed ID24665408
Zonula occludens-2 regulates Rho proteins activity and the development of epithelial cytoarchitecture and barrier function.
Authors
JournalBiochim Biophys Acta Mol Cell Res
PubMed ID28554775
Unbiased Analysis Method for Measurement of Red Blood Cell Size and Velocity With Laser Scanning Microscopy.
Authors
JournalFront Neurosci
PubMed ID31316334
Real-time brain-wide multi-planar microscopy for simultaneous cortex and hippocampus imaging at the cellular resolution in mice.
Authors
JournalBiomed Opt Express
PubMed ID33996203
Placozoan fiber cells: mediators of innate immunity and participants in wound healing.
Authors
JournalSci Rep
PubMed ID34857844
Injured Podocytes Are Sensitized to Angiotensin II-Induced Calcium Signaling.
Authors
JournalJ Am Soc Nephrol
PubMed ID31924670
Cerebral capillary blood flow upsurge during REM sleep is mediated by A2a receptors.
Authors
JournalCell Rep
PubMed ID34407410
Activation of Glutamate Transport Increases Arteriole Diameter in v ivo: Implications for Neurovascular Coupling.
Authors
JournalFront Cell Neurosci
PubMed ID35308116
Astrocytic neogenin/netrin-1 pathway promotes blood vessel homeostasis and function in mouse cortex.
Authors
JournalJ Clin Invest
PubMed ID32853179
Cancer Cells Resist Mechanical Destruction in Circulation via RhoA/Actomyosin-Dependent Mechano-Adaptation.