Clathrin-mediated endocytosis near active zones in snake motor boutons.
AuthorsTeng H,Wilkinson RS
JournalThe Journal of neuroscience : the official journal of the Society for Neuroscience
PubMed ID11050119
We have used the activity-dependent probe FM1-43 with electron microscopy (EM) to examine endocytosis at the vertebrate nerveâmuscle synapse. Preparations were fixed after very brief neural stimulation at reduced temperature, and internalized FM1-43 was photoconverted into an electron-dense reaction product. To locate the reaction product, we reconstructed computer renderings of ... More
Properties of fast endocytosis at hippocampal synapses.
AuthorsKavalali ET,Klingauf J,Tsien RW
JournalPhilosophical transactions of the Royal Society of London. Series B, Biological sciences
PubMed ID10212482
Regulation of synaptic transmission is a widespread means for dynamic alterations in nervous system function. In several cases, this regulation targets vesicular recycling in presynaptic terminals and may result in substantial changes in efficiency of synaptic transmission. Traditionally, experimental accessibility of the synaptic vesicle cycle in central neuronal synapses has ... More
Endosome fusion and microtubule-based dynamics in the early endocytic pathway of dictyostelium.
AuthorsClarke M, Köhler J, Heuser J, Gerisch G
JournalTraffic
PubMed ID12383345
Dictyostelium amoebae, like mammalian macrophages, take up fluid by macropinocytosis. The present study used fluorescent fluid-phase markers and GFP-labeled microtubules to visualize the uptake, dynamics, and fusion of early endosomes in Dictyostelium. Consecutive labeling with two fluorescent fluid-phase markers demonstrated that within the first few minutes after uptake, new macropinosomes ... More
High spatial resolution confocal microscopy of young MDCK cells stained with the lipophilic probe 1,1'-dihexadecyl-3,3,3',3'- tetramethylindocarbocyanine perchlorate (DiIC(16)) revealed a reticulated fluorescence pattern on the apical membrane. DiIC(16) was delivered as crystals to live cells to minimize possible solvent perturbations of the membrane lipids. The ratio of the integrated fluorescence ... More
Visualization of changes in presynaptic function during long-term synaptic plasticity.
AuthorsZakharenko SS, Zablow L, Siegelbaum SA
JournalNat Neurosci
PubMed ID11426227
Controversy exists regarding the site of modification of synaptic transmission during long-term plasticity in the mammalian hippocampus. Here we used a fluorescent marker of presynaptic activity, FM 1-43, to directly image changes in presynaptic function during both short-term and long-term forms of plasticity at presynaptic boutons of CA3-CA1 excitatory synapses ... More
A developmental switch in neurotransmitter flux enhances synaptic efficacy by affecting AMPA receptor activation.
AuthorsRenger JJ, Egles C, Liu G
JournalNeuron
PubMed ID11239436
'Formation of glutamatergic synapses entails development of "silent" immature contacts into mature functional synapses. To determine how this transformation occurs, we investigated the development of neurotransmission at single synapses in vitro. Maturation of presynaptic function, assayed with endocytotic markers, followed accumulation of synapsin I. During this period, synaptic transmission was ... More
Drosophila Hsc70-4 is critical for neurotransmitter exocytosis in vivo.
AuthorsBronk P, Wenniger JJ, Dawson-Scully K, Guo X, Hong S, Atwood HL, Zinsmaier KE
JournalNeuron
PubMed ID11395008
'Previous in vitro studies of cysteine-string protein (CSP) imply a potential role for the clathrin-uncoating ATPase Hsc70 in exocytosis. We show that hypomorphic mutations in Drosophila Hsc70-4 (Hsc4) impair nerve-evoked neurotransmitter release, but not synaptic vesicle recycling in vivo. The loss of release can be restored by increasing external or ... More
Focal exocytosis of VAMP3-containing vesicles at sites of phagosome formation.
AuthorsBajno L, Peng XR, Schreiber AD, Moore HP, Trimble WS, Grinstein S
JournalJ Cell Biol
PubMed ID10791982
'Phagocytosis involves the receptor-mediated extension of plasmalemmal protrusions, called pseudopods, which fuse at their tip to engulf a particle. Actin polymerizes under the nascent phagosome and may propel the protrusion of pseudopods. Alternatively, membrane extension could result from the localized insertion of intracellular membranes into the plasmalemma next to the ... More
Long-term maintenance of presynaptic function in the absence of target muscle fibers.
AuthorsDunaevsky A, Connor EA
JournalJ Neurosci
PubMed ID7666196
'Here we have investigated the role of the muscle fiber in the maintenance of presynaptic function at frog motor nerve terminals. Muscle fibers were selectively damaged and prevented from regenerating while leaving the motor innervation intact. Presynaptic activity of the resulting target-deprived nerve terminals was assayed using the fluorescent dye, ... More
Proliferation of functional hair cells in vivo in the absence of the retinoblastoma protein.
'In mammals, hair cell loss causes irreversible hearing and balance impairment because hair cells are terminally differentiated and do not regenerate spontaneously. By profiling gene expression in developing mouse vestibular organs, we identified the retinoblastoma protein (pRb) as a candidate regulator of cell cycle exit in hair cells. Differentiated and ... 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
Nectin: an adhesion molecule involved in formation of synapses.
AuthorsMizoguchi A, Nakanishi H, Kimura K, Matsubara K, Ozaki-Kuroda K, Katata T, Honda T, Kiyohara Y, Heo K, Higashi M, Tsutsumi T, Sonoda S, Ide C, Takai Y
JournalJ Cell Biol
PubMed ID11827984
'The nectin-afadin system is a novel cell-cell adhesion system that organizes adherens junctions cooperatively with the cadherin-catenin system in epithelial cells. Nectin is an immunoglobulin-like adhesion molecule, and afadin is an actin filament-binding protein that connects nectin to the actin cytoskeleton. Nectin has four isoforms (-1, -2, -3, and -4). ... More
Okadaic acid disrupts clusters of synaptic vesicles in frog motor nerve terminals.
AuthorsBetz WJ, Henkel AW
JournalJ Cell Biol
PubMed ID8120104
'The fluorophore FM1-43 appears to stain membranes of recycled synaptic vesicles. We used FM1-43 to study mechanisms of synaptic vesicle clustering and mobilization in living frog motor nerve terminals. FM1-43 staining of these terminals produces a linear series of fluorescent spots, each spot marking the cluster of several hundred synaptic ... More
Empty synaptic vesicles recycle and undergo exocytosis at vesamicol-treated motor nerve terminals.
AuthorsParsons RL, Calupca MA, Merriam LA, Prior C
JournalJ Neurophysiol
PubMed ID10368389
'We investigated whether recycled cholinergic synaptic vesicles, which were not refilled with ACh, would join other synaptic vesicles in the readily releasable store near active zones, dock, and continue to undergo exocytosis during prolonged stimulation. Snake nerve-muscle preparations were treated with 5 microM vesamicol to inhibit the vesicular ACh transporter ... More
Somatic exocytosis of serotonin mediated by L-type calcium channels in cultured leech neurones.
AuthorsTrueta C, Méndez B, De-Miguel FF
JournalJ Physiol
PubMed ID12562971
'We studied somatic exocytosis of serotonin and its mediation by L-type calcium (Ca2+) channels in cultured Retzius neurones of the leech. Exocytosis was induced by trains of impulses at different frequencies or by depolarisation with 40 mM potassium (K+), and was quantified by use of the fluorescent dye FM 1-43. ... More
Electrical resonance and Ca2+ influx in the synaptic terminal of depolarizing bipolar cells from the goldfish retina.
AuthorsBurrone J, Lagnado L
JournalJ Physiol
PubMed ID9457636
'1. Whole-cell recordings and fura-2 measurements of cytoplasmic [Ca2+] were made in depolarizing bipolar cells isolated from the retinae of goldfish. The aim was to study the voltage signal that regulates Ca2+ influx in the synaptic terminal. 2. The current-voltage relation was linear up to about -44 mV. At this ... More
Quantitative measurement of mast cell degranulation using a novel flow cytometric annexin-V binding assay.
AuthorsDemo SD, Masuda E, Rossi AB, Throndset BT, Gerard AL, Chan EH, Armstrong RJ, Fox BP, Lorens JB, Payan DG, Scheller RH, Fisher JM
JournalCytometry
PubMed ID10404150
'BACKGROUND: Mast cells are primary mediators of allergic inflammation. Antigen-mediated crosslinking of their cell surface immunoglobulin E (IgE) receptors results in degranulation and the release of proinflammatory mediators including histamine, tumor necrosis factor-alpha, and leukotrienes. METHODS: Mast cells were stimulated to degranulate by using either IgE crosslinking or ionophore treatment. ... More
Control of secretion by temporal patterns of action potentials in adrenal chromaffin cells.
AuthorsDuan K, Yu X, Zhang C, Zhou Z
JournalJ Neurosci
PubMed ID14657183
'Action potentials (APs) are the principal physiological stimuli for neurotransmitter secretion in neurons. Most studies on stimulus-secretion coupling have been performed under voltage clamp using artificial electrical stimuli. To investigate the modulatory effects of AP codes on neural secretion, we introduce a capacitance method to study AP-induced secretion in single ... More
Na+ channel-mediated Ca2+ entry leads to glutamate secretion in mouse neocortical preplate.
AuthorsPlatel JC, Boisseau S, Dupuis A, Brocard J, Poupard A, Savasta M, Villaz M, Albrieux M
JournalProc Natl Acad Sci U S A
PubMed ID16357207
'Before synaptogenesis, early excitability implicating voltage-dependent and transmitter-activated channels is known to be crucial for neuronal development. We previously showed that preplate (PP) neurons of the mouse neocortex express functional Na(+) channels as early as embryonic day 12. In this study, we investigated the role of these Na(+) channels in ... More
Kinetics of synaptic depression and vesicle recycling after tetanic stimulation of frog motor nerve terminals.
AuthorsWu LG, Betz WJ
JournalBiophys J
PubMed ID9635754
'We measured the time courses of two key components of the synaptic vesicle cycle during recovery from synaptic depression under different conditions, and used this and other information to create a kinetic model of the vesicle cycle. End plate potential (EPP) amplitudes were used to follow recovery from synaptic depression ... More
Clusters of GABAA receptors on cultured hippocampal cells correlate only partially with functional synapses.
AuthorsKannenberg K, Sieghart W, Reuter H
JournalEur J Neurosci
PubMed ID10103120
'We describe a method to label gamma-aminobutyric acid (GABA)A receptors on the surface of living hippocampal neurons in primary culture, and we compare the distribution of receptors with that of active synapses. To visualize GABAA receptors, the affinity-purified antibody beta3(1-13), recognizing the extracellular N-termini of the GABAA receptor beta2- and ... More
Two modes of vesicle recycling in the rat calyx of Held.
Authorsde Lange RP, de Roos AD, Borst JG
JournalJ Neurosci
PubMed ID14602833
'Vesicle recycling was studied in the rat calyx of Held, a giant brainstem terminal involved in sound localization. Stimulation of brain slices containing the calyx-type synapse with a high extracellular potassium ion concentration in the presence of horseradish peroxidase resulted within several minutes in a reduction of the number of ... More
Long-term staining of live Merkel cells with FM dyes.
AuthorsFukuda J, Ishimine H, Masaki Y
JournalCell Tissue Res
PubMed ID12658440
'Live Merkel cells in the skin and hair follicles are known to incorporate a fluorescence dye, quinacrine, which has been utilized to identify and dissect the cells for experiments. Quinacrine fluorescence of the cells is, however, quickly lost and quinacrine-stained Merkel cells soon become difficult to identify in tissue culture. ... More
Compartmentalized IgE receptor-mediated signal transduction in living cells.
AuthorsStauffer TP, Meyer T
JournalJ Cell Biol
PubMed ID9396750
'Several receptor-mediated signal transduction pathways, including EGF and IgE receptor pathways, have been proposed to be spatially restricted to plasma membrane microdomains. However, the experimental evidence for signaling events in these microdomains is largely based on biochemical fractionation and immunocytochemical studies and only little is known about their spatial dynamics ... More
Two mechanisms of synaptic vesicle recycling in rat brain nerve terminals.
AuthorsCousin MA, Robinson PJ
JournalJ Neurochem
PubMed ID10987846
'KCl and 4-aminopyridine (4-AP) evoke glutamate release from rat brain cortical nerve terminals by voltage clamping or by Na(+) channel-generated repetitive action potentials, respectively. Stimulation by 4-AP but not KCl is largely mediated by protein kinase C (PKC). To determine whether KCl and 4-AP utilise the same mechanism to release ... More
Phosphatidylinositol 4,5-bisphosphate functions as a second messenger that regulates cytoskeleton-plasma membrane adhesion.
AuthorsRaucher D, Stauffer T, Chen W, Shen K, Guo S, York JD, Sheetz MP, Meyer T
JournalCell
PubMed ID10660045
'Binding interactions between the plasma membrane and the cytoskeleton define cell functions such as cell shape, formation of cell processes, cell movement, and endocytosis. Here we use optical tweezers tether force measurements and show that plasma membrane phosphatidylinositol 4,5-bisphosphate (PIP2) acts as a second messenger that regulates the adhesion energy ... More
Elemental propagation of calcium signals in response-specific patterns determined by environmental stimulus strength.
AuthorsGoddard H, Manison NF, Tomos D, Brownlee C
JournalProc Natl Acad Sci U S A
PubMed ID10677557
'Plant cells can respond qualitatively and quantitatively to a wide range of environmental signals. Ca(2+) is used as an intracellular signal for volume regulation in response to external osmotic changes. We show here that the spatiotemporal patterns of hypo-osmotically induced Ca(2+) signals vary dramatically with stimulus strength in embryonic cells ... More
A cell-free system for regulated exocytosis in PC12 cells.
AuthorsAvery J, Ellis DJ, Lang T, Holroyd P, Riedel D, Henderson RM, Edwardson JM, Jahn R
JournalJ Cell Biol
PubMed ID10648564
'We have developed a cell-free system for regulated exocytosis in the PC12 neuroendocrine cell line. Secretory vesicles were preloaded with acridine orange in intact cells, and the cells were sonicated to produce flat, carrier-supported plasma membrane patches with attached vesicles. Exocytosis resulted in the release of acridine orange which was ... More
Heterogeneous release properties of visualized individual hippocampal synapses.
AuthorsMurthy VN, Sejnowski TJ, Stevens CF
JournalNeuron
PubMed ID9136769
'We have used endocytotic uptake of the styryl dye FM1-43 at synaptic terminals (Betz and Bewick, 1992) to study properties of individual synapses formed by axons of single hippocampal neurons in tissue culture. The distribution of values for probability of evoked transmitter release p estimated by dye uptake is continuous, ... More
Direct monitoring of vesicular release and uptake in brain slices by multiphoton excitation of the styryl FM 1-43.
AuthorsWinterer J, Stanton PK, Müller W
JournalBiotechniques
PubMed ID16568823
'Fluorescence imaging using FM 1-43 and related styryl dyes has provided invaluable insights into presynaptic function of synapses in culture preparations, but has been limited in use for studying central synapses in vivo or in brain slices, because of excessive fluorescence background due to nonspecific membrane binding of dye. We ... More
Dynamics of the mitochondrial reticulum in live cells using Fourier imaging correlation spectroscopy and digital video microscopy.
AuthorsMargineantu D, Capaldi RA, Marcus AH
JournalBiophys J
PubMed ID11023889
'We report detailed studies of the dynamics of the mitochondrial reticulum in live cells using two independent experimental techniques: Fourier imaging correlation spectroscopy and digital video fluorescence microscopy. When both methods are used to study the same system, it is possible to directly compare measurements of preaveraged statistical dynamical quantities ... More
Two-photon laser-scanning microscopy: tests of objective lenses and Ca2+ probes.
AuthorsKuba K, Nakayama S
JournalNeurosci Res
PubMed ID9875569
'The characteristics of objective lenses and Ca2+-sensitive probes were examined for imaging with a two-photon laser-scanning microscope (TP-LSM). The brightness of the images of beads taken by different objectives greatly varied and depended predominantly on their numerical aperture (NA) and less on transmittance and chirping effects. Lateral and axial resolutions, ... More
Mechanical forces impeding exocytotic surfactant release revealed by optical tweezers.
AuthorsSinger W, Frick M, Haller T, Bernet S, Ritsch-Marte M, Dietl P
JournalBiophys J
PubMed ID12547815
'The release of surfactant from alveolar type II cells is essential to lower the surface tension in the lung and to facilitate inspiration. However, the factors controlling dispersal and diffusion of this hydrophobic material are still poorly understood. Here we report that release of surfactant from the fused vesicle, termed ... More
Glutamate exocytosis from cerebellar granule cells: the mechanism of a transition to an L-type Ca2+ channel coupling.
'When cerebellar granule cells in the presence of 1.3 mM calcium chloride (Ca2+) are depolarized by high potassium chloride (KCl), the release of endogenous glutamate is coupled to a high threshold Ca2+ channel blocked by the spider toxin omega Agatoxin-glutamate-release-inhibitor (Aga-GI) and insensitive to the L-type voltage-dependent Ca2+ channel-inhibitor nifedipine. ... More
A toxin from the spider Phoneutria nigriventer that blocks calcium channels coupled to exocytosis.
AuthorsGuatimosim C, Romano-Silva MA, Cruz JS, Beirão PS, Kalapothakis E, Moraes-Santos T, Cordeiro MN, Diniz CR, Gomez MV, Prado MA
JournalBr J Pharmacol
PubMed ID9351520
'1. The aim of the present experiments was to investigate the pharmacological action of a toxin from the spider Phoneutria nigriventer, Tx3-3, on the function of calcium channels that control exocytosis of synaptic vesicles. 2. Tx3-3, in confirmation of previous work, diminished the intracellular calcium increase induced by membrane depolarization ... More
PHYTOCHROME KINASE SUBSTRATE 1 is a phototropin 1 binding protein required for phototropism.
AuthorsLariguet P, Schepens I, Hodgson D, Pedmale UV, Trevisan M, Kami C, de Carbonnel M, Alonso JM, Ecker JR, Liscum E, Fankhauser C
JournalProc Natl Acad Sci U S A
PubMed ID16777956
'Phototropism, or plant growth in response to unidirectional light, is an adaptive response of crucial importance. Lateral differences in low fluence rates of blue light are detected by phototropin 1 (phot1) in Arabidopsis. Only NONPHOTOTROPIC HYPOCOTYL 3 (NPH3) and root phototropism 2, both belonging to the same family of proteins, ... More
A candidate gene for the mouse mutation tubby.
AuthorsNoben-Trauth K, Naggert JK, North MA, Nishina PM
JournalNature
PubMed ID8606774
'A mutation in the tub gene causes maturity-onset obesity, insulin resistance, and sensory deficits. In contrast to the rapid juvenile-onset weight gain seen in diabetes (db) and obese (ob) mice, obesity in tubby mice develops gradually, and strongly resembles the late-onset obesity seen in the human population. Excessive deposition of ... More
Bulk membrane retrieval in the synaptic terminal of retinal bipolar cells.
AuthorsHolt M, Cooke A, Wu MM, Lagnado L
JournalJ Neurosci
PubMed ID12598621
'The mechanism of bulk membrane uptake at the synapse remains poorly defined, although exocytosis of synaptic vesicles is followed by compensatory membrane retrieval into both small vesicles and large cisternas or vacuoles. We investigated bulk retrieval in the presynaptic terminal of retinal bipolar cells. Fluorescence imaging of the membrane dye ... More
An inhibitory role of calcineurin in endocytosis of synaptic vesicles at nerve terminals of Drosophila larvae.
AuthorsKuromi H, Yoshihara M, Kidokoro Y
JournalNeurosci Res
PubMed ID9100252
'In this study, we tested a hypothesis that activation of calcineurin, Ca2+/calmodulin-dependent protein phosphatase 2B, is an initiating signal for synaptic vesicle endocytosis. We examined effects of calcineurin inhibitors, cyclosporin A or FK506 and calmodulin inhibitors on stimulus-induced FM1-43 uptake into nerve terminals of Drosophila larvae. Fluorescent FM1-43 labels recycling ... More
Cell death-associated translocation of plasma membrane components induced by CTL.
AuthorsKawasaki Y, Saito T, Shirota-Someya Y, Ikegami Y, Komano H, Lee MH, Froelich CJ, Shinohara N, Takayama H
JournalJ Immunol
PubMed ID10779768
'In the very early stages of target cell apoptosis induced by CTL, we found that fluorescence of labeling probes of the target plasma membrane, such as N-(3-triethylammoniumpropyl)-4-(p-dibutylaminostyryl)pyridin ium dibromide (FM1-43), was translocated into intracellular membrane structures including nuclear envelope and mitochondria. This translocation was associated with the execution of CTL-mediated ... More
Comparison of FM1-43 staining patterns and electrophysiological measures of transmitter release at the frog neuromuscular junction.
AuthorsBetz WJ, Ridge RM, Bewick GS
JournalJ Physiol Paris
PubMed ID7511018
'Frog motor nerve terminals were stained with the activity-dependent dye FM1-43, which appears to stain recycled synaptic vesicles. Superficial end plates which could be visualized in their entirety were imaged and end plate potentials (EPPs) evoked by low frequency nerve stimulation were recorded from the muscle fibers which were innervated ... More
The synaptic vesicle cycle.
AuthorsBetz WJ, Angleson JK
JournalAnnu Rev Physiol
PubMed ID9558468
'The ins and outs of the synaptic vesicle cycle are being examined in increasing detail with diverse investigative tools in a variety of cell types, particularly those with large granules. The cycle begins with the opening of a fusion pore that connects the vesicle lumen to the extracellular fluid. Sensitive ... More
Intracellular acidification reversibly reduces endocytosis at the neuromuscular junction.
AuthorsLindgren CA, Emery DG, Haydon PG
JournalJ Neurosci
PubMed ID9096142
'The close spatial and temporal coupling of endocytosis and exocytosis in nerve terminals has made it difficult to elucidate the mechanisms and the regulation of endocytosis per se. Despite significant advances in our knowledge of the molecules involved in endocytosis, it has not yet been possible to selectively manipulate endocytosis ... More
Synaptic vesicle dynamics in rat fast and slow motor nerve terminals.
AuthorsReid B, Slater CR, Bewick GS
JournalJ Neurosci
PubMed ID10087065
'We have investigated whether rat motor nerve terminals with different in vivo activity patterns also have different vesicle trafficking characteristics. To do this, we monitored, using combined optical and electrical techniques, the rate of exocytosis (during different frequencies and patterns of activity), the releasable pool size, and the recycle time ... More
The timing of synaptic vesicle endocytosis.
AuthorsRyan TA, Smith SJ, Reuter H
JournalProc Natl Acad Sci U S A
PubMed ID8643616
'Alternative models to describe the endocytosis phase of synaptic vesicle recycling are associated with time scales of vesicle recovery ranging from milliseconds to tens of seconds. There have been suggestions that one of the major models, envisioned as a slow process that occurs only after complete fusion of the vesicle ... More
Calmodulin and immunophilin are required as functional partners of a ryanodine receptor in ascidian oocytes at fertilization.
AuthorsAlbrieux M, Moutin MJ, Grunwald D, Villaz M
JournalDev Biol
PubMed ID10964467
'Fertilization of oocytes incites numerous changes relying on Ca(2+) signaling. In inseminated ascidian eggs, an increase in the egg surface membrane, monitored by a change in electrical capacitance, is recorded at the onset of meiosis resumption. This membrane addition to the cell surface is controlled by calcium release through a ... More
Calcitonin stimulates lysosomal enzyme release and uptake in LLC-PK1 cells.
AuthorsGoto M, Mizunashi K
JournalJ Am Soc Nephrol
PubMed ID10446931
'Renal tubular targeted hormones increase urinary excretion of a lysosomal enzyme, N-acetyl-beta-D-glucosaminidase (NAG). To elucidate the mechanism of this event, the calcitonin effect on NAG handling by LLC-PK1 cells was examined. Calcitonin (1 nM to 1 microM), phorbol myristate (10 nM to 1 microM), and ionomycin (1 to 10 microM) ... More
The mechanism of facilitated cell membrane resealing.
AuthorsTogo T, Alderton JM, Bi GQ, Steinhardt RA
JournalJ Cell Sci
PubMed ID9973606
'Disruption of the plasma membrane evokes an exocytotic response that is required for rapid membrane resealing. We show here in Swiss 3T3 fibroblasts that a second disruption at the same site reseals more rapidly than the initial wound. This facilitated response of resealing was inhibited by both low external Ca2+ ... More
Presynaptic function during muscle remodeling in insect metamorphosis.
AuthorsConsoulas C, Levine RB
JournalJ Neurosci
PubMed ID9671669
'During metamorphosis the leg neuromuscular system of the moth Manduca sexta undergoes an extensive remodeling as the larval muscles degenerate and are replaced by new muscles in the adult. The terminal processes of persistent leg motoneurons undergo severe regression followed by regrowth (Consoulas et al., 1996), accompanied, as shown here, ... More
High-resolution iontophoresis for single-synapse stimulation.
AuthorsMurnick JG, Dubé G, Krupa B, Liu G
JournalJ Neurosci Methods
PubMed ID12007984
'We present a technique for stimulating post-synaptic receptors with neurotransmitter locally at a single synapse and with a concentration profile that is comparable to endogenous stimulation. We modify the technique of iontophoresis to use a 0.1 microm electrode tip for local stimulation, and we combine it with fast capacitance compensation ... More
Role of mitochondrial dysfunction in the Ca2+-induced decline of transmitter release at K+-depolarized motor neuron terminals.
'The present study tested whether a Ca2+-induced disruption of mitochondrial function was responsible for the decline in miniature endplate current (MEPC) frequency that occurs with nerve-muscle preparations maintained in a 35 mM potassium propionate (35 mM KP) solution containing elevated calcium. When the 35 mM KP contained control Ca2+ (1 ... More
Visualization of exocytosis during sea urchin egg fertilization using confocal microscopy.
AuthorsTerasaki M
JournalJ Cell Sci
PubMed ID7673349
'A Ca2+ wave at fertilization triggers cortical granule exocytosis in sea urchin eggs. New methods for visualizing exocytosis of individual cortical granules were developed using fluorescent probes and confocal microscopy. Electron microscopy previously provided evidence that cortical granule exocytosis results in the formation of long-lived depressions in the cell surface. ... More
Exocytosis and selective neurite calcium responses in rat cerebellar granule cells during field stimulation.
AuthorsCousin MA, Held B, Nicholls DG
JournalEur J Neurosci
PubMed ID8845942
'The free calcium concentration, [Ca2+]c, in fura-2-loaded rat cerebellar granule cells was investigated by digital imaging during trains of uniform field stimuli in order to compare the ability of calcium channels in somata and neurites to respond to brief, physiologically relevant depolarizations. Very few somata responded to 20 Hz trains ... More
Ca2+ influx-independent synaptic potentiation mediated by mitochondrial Na(+)-Ca2+ exchanger and protein kinase C.
AuthorsYang F, He XP, Russell J, Lu B
JournalJ Cell Biol
PubMed ID14610054
'Activity-dependent modulation of synaptic transmission is an essential mechanism underlying many brain functions. Here we report an unusual form of synaptic modulation that depends on Na+ influx and mitochondrial Na(+)-Ca2+ exchanger, but not on Ca2+ influx. In Ca(2+)-free medium, tetanic stimulation of Xenopus motoneurons induced a striking potentiation of transmitter ... More
Phospholipid scramblase activation pathways in lymphocytes.
AuthorsWilliamson P, Christie A, Kohlin T, Schlegel RA, Comfurius P, Harmsma M, Zwaal RF, Bevers EM
JournalBiochemistry
PubMed ID11434775
'In erythrocytes and platelets, activation of a nonspecific lipid flipsite termed the scramblase allows rapid, bidirectional transbilayer movement of all types of phospholipids. When applied to lymphoid cells, scramblase assays reveal a similar activity, with scrambling rates intermediate between those seen in platelets and erythrocytes. Scrambling activity initiated in lymphoid ... More
FM1-43 is a permeant blocker of mechanosensitive ion channels in sensory neurons and inhibits behavioural responses to mechanical stimuli.
AuthorsDrew LJ, Wood JN,
JournalMol Pain
PubMed ID17207285
'The molecular identity and pharmacological properties of mechanically gated ion channels in sensory neurons are poorly understood. We show that FM1-43, a styryl dye used to fluorescently label cell membranes, permeates mechanosensitive ion channels in cultured dorsal root ganglion neurons, resulting in blockade of three previously defined subtypes of mechanically ... More
Visualization of sequential exocytosis in rat pancreatic islet beta cells.
AuthorsLeung YM, Sheu L, Kwan E, Wang G, Tsushima R, Gaisano H
JournalBiochem Biophys Res Commun
PubMed ID11944911
'The examination of insulin exocytosis at the single cell level by conventional electrophysiologic and amperometric methods possesses inherent limitations, and may not accurately reflect the morphologic events of exocytosis of the insulin granule. To overcome some of these limitations, we show by epifluorescent microscopy of a fluorescent dye, FM1-43, its ... More
Osmotically evoked shrinking of guard-cell protoplasts causes vesicular retrieval of plasma membrane into the cytoplasm.
AuthorsKubitscheck U, Homann U, Thiel G
JournalPlanta
PubMed ID10750900
'The dye FM1-43 was used alone or in combination with measurements of the membrane capacitance (Cm) to monitor membrane changes in protoplasts from Vicia faba L. guard cells. Confocal images of protoplasts incubated with FM1-43 (10 microM) at constant ambient osmotic pressure (pi omicron) revealed in confocal images a slow ... More
Properties of synaptic transmission at single hippocampal synaptic boutons.
AuthorsLiu G, Tsien RW
JournalNature
PubMed ID7760934
'Synaptic transmission between individual presynaptic terminals and postsynaptic dendrites is a fundamental element of communication among central nervous system neurons. Yet little is known about evoked neurotransmission at the level of single presynaptic boutons. Here we describe key functional characteristics of individual presynaptic boutons of hippocampal neurons in culture. Excitatory ... More
Real-time analysis of the role of Ca(2+) in flagellar movement and motility in single sea urchin sperm.
AuthorsWood CD, Nishigaki T, Furuta T, Baba SA, Darszon A
JournalJ Cell Biol
PubMed ID15928204
'Eggs of many marine and mammalian species attract sperm by releasing chemoattractants that modify the bending properties of flagella to redirect sperm paths toward the egg. This process, called chemotaxis, is dependent on extracellular Ca(2+). We used stroboscopic fluorescence imaging to measure intracellular Ca(2+) concentration ([Ca(2+)]i) in the flagella of ... More
Actin disassembles reversibly during electrically induced recycling of synaptic vesicles in cultured neurons.
AuthorsBernstein BW, DeWit M, Bamburg JR
JournalBrain Res Mol Brain Res
PubMed ID9473683
'We have studied depolarization-induced regulation of actin assembly in exocytotically active areas of dissociated chick sympathetic neurons. Active areas were identified with the fluorescent dye FM1-43 which labels synaptic vesicles that recycle in these regions. Exocytosis (electrically stimulated) was monitored in real time through depletion of FM1-43 fluorescence. To study ... More
Early synaptogenesis in vitro: role of axon target distance.
Authorsvan den Pol AN, Obrietan K, Belousov AB, Yang Y, Heller HC
JournalJ Comp Neurol
PubMed ID9741482
'In contrast to some previous reports suggesting a delay in synapse formation in vitro, we found that under ideal conditions, most hippocampal and hypothalamic rat neurons were synaptically coupled after 3 or 4 days in vitro. Synaptophysin immunocytochemistry revealed strongly stained presynaptic boutons by 3 days in vitro. Studies with ... More
Optical monitoring of the neural activity evoked by mechanical stimulation in the earthworm nervous system with a fluorescent dye, FM1-43.
AuthorsShimizu R, Oka K, Ogawa H, Suzuki K, Saito J, Mizutani K, Tanishita K
JournalNeurosci Lett
PubMed ID10406029
'In the central nervous system of the earthworm, sensory and motor neurons have direct synapses on three giant fibers. To determine the locations of synapses and neural network activated by mechanical stimuli, we optically monitored the activity-dependent staining in the earthworm ventral nerve cord with a styryl dye, N-(3-triethylammoniumpropyl)-4- (4-(dibutylamino)styryl)pyridinium ... More
Membrane expansion increases endocytosis rate during mitosis.
AuthorsRaucher D, Sheetz MP
JournalJ Cell Biol
PubMed ID9971744
'Mitosis in mammalian cells is accompanied by a dramatic inhibition of endocytosis. We have found that the addition of amphyphilic compounds to metaphase cells increases the endocytosis rate even to interphase levels. Detergents and solvents all increased endocytosis rate, and the extent of increase was in direct proportion to the ... More
Motor deficit in a Drosophila model of mucolipidosis type IV due to defective clearance of apoptotic cells.
'Disruption of the Transient Receptor Potential (TRP) mucolipin 1 (TRPML1) channel results in the neurodegenerative disorder mucolipidosis type IV (MLIV), a lysosomal storage disease with severe motor impairments. The mechanisms underlying MLIV are poorly understood and there is no treatment. Here, we report a Drosophila MLIV model, which recapitulates the ... More
Optical measurement of stimulus-evoked membrane dynamics in single pancreatic acinar cells.
AuthorsGiovannucci DR, Yule DI, Stuenkel EL
JournalAm J Physiol
PubMed ID9730956
'Stimulation of pancreatic acinar cells induces the release of digestive enzymes via the exocytotic fusion of zymogen granules and activates postfusion granule membrane retrieval and receptor cycling. In the present study, changes in membrane surface area of rat single pancreatic acinar cells were monitored by cell membrane capacitance (Cm) measurements ... More
The wheat proteins puroindoline-a and alpha1-purothionin induce nodal swelling in myelinated axons.
AuthorsMattei C, Elmorjani K, Molgó J, Marion D, Benoit E
JournalNeuroreport
PubMed ID9875708
'The effects of two basic cysteine-rich lipid-binding proteins isolated from wheat seedlings, puroindoline-a and alpha1-purothionin, were studied on single frog myelinated axons stained with the fluorescent dye FM1-43 using confocal laser scanning microscopy. During exposure to either puroindoline-a or alpha1-purothionin (10 and 100 microM) a marked swelling of nodes of ... More
TRPA1 is a candidate for the mechanosensitive transduction channel of vertebrate hair cells.
AuthorsCorey DP, García-Añoveros J, Holt JR, Kwan KY, Lin SY, Vollrath MA, Amalfitano A, Cheung EL, Derfler BH, Duggan A, Géléoc GS, Gray PA, Hoffman MP, Rehm HL, Tamasauskas D, Zhang DS
JournalNature
PubMed ID15483558
'Mechanical deflection of the sensory hair bundles of receptor cells in the inner ear causes ion channels located at the tips of the bundle to open, thereby initiating the perception of sound. Although some protein constituents of the transduction apparatus are known, the mechanically gated transduction channels have not been ... More
Circulation of the plasma membrane in Dictyostelium.
AuthorsAguado-Velasco C, Bretscher MS
JournalMol Biol Cell
PubMed ID10588667
'We have developed a fluorimetric assay with the use of the dye FM1-43 to determine the rate at which Dictyostelium amoebae endocytose their surface membrane. Our results show that they do so about once each 4-10 min. A clathrin null mutant takes its surface up only approximately 30% more slowly, ... More
Differential regulation of granule-to-granule and granule-to-plasma membrane fusion during secretion from rat pituitary lactotrophs.
AuthorsCochilla AJ, Angleson JK, Betz WJ
JournalJ Cell Biol
PubMed ID10953007
'We used fluorescence imaging of individual exocytic events together with electron microscopy to study the regulation of dense core granule-to-plasma membrane fusion and granule-to-granule fusion events that occur during secretion from rat pituitary lactotrophs. Stimulating secretion with elevated extracellular potassium, with the calcium ionophore ionomycin, or with thyrotropin releasing hormone ... More
Synaptic vesicles retain their identity through the endocytic cycle.
AuthorsMurthy VN, Stevens CF
JournalNature
PubMed ID9548254
'After fusion of synaptic vesicles with presynaptic membrane and secretion of the contents of the vesicles into the synaptic cleft (a process known as exocytosis), the vesicular membrane is retrieved by endocytosis (internalization) for re-use. Several issues regarding endocytosis at central synapses are unresolved, including the location of membrane retrieval ... More
Continuous and transient vesicle cycling at a ribbon synapse.
AuthorsRouze NC, Schwartz EA
JournalJ Neurosci
PubMed ID9786969
'Optical methods were used to study the Ca2+ dependence of vesicle cycling in bipolar cells isolated from goldfish retinas. Uniformly raising the Ca2+ concentration to between 0.8 and 20 microM produced a continuous vesicle cycle of balanced exocytosis and endocytosis with a maximum rate equivalent to the turnover of the ... More
Exocytotic and nonexocytotic modes of glutamate release from cultured cerebellar granule cells during chemical ischaemia.
AuthorsPocock JM, Nicholls DG
JournalJ Neurochem
PubMed ID9453577
'The mechanism of glutamate release from cultured cerebellar granule neurones in response to a chemical model of ischaemia (10 mM 2-deoxyglucose plus 1 mM sodium cyanide) was investigated. In the first 2 min of ischaemia, release of preloaded D-[3H]aspartate could be extensively attenuated by tetanus toxin and bafilomycin A1 and ... More
GPI-anchored influenza hemagglutinin induces hemifusion to both red blood cell and planar bilayer membranes.
AuthorsMelikyan GB, White JM, Cohen FS
JournalJ Cell Biol
PubMed ID7593189
'Under fusogenic conditions, fluorescent dye redistributed from the outer monolayer leaflet of red blood cells (RBCs) to cells expressing glycophosphatidylinositol-anchored influenza virus hemagglutinin (GPI-HA) without transfer of aqueous dye. This suggests that hemifusion, but not full fusion, occurred (Kemble, G. W., T. Danieli, and J. M. White. 1994. Cell. 76:383-391). ... More
FM dyes label sterol-rich plasma membrane domains and are internalized independently of the cytoskeleton in characean internodal cells.
AuthorsKlima A, Foissner I,
JournalPlant Cell Physiol
PubMed ID18757863
'We applied the endocytic markers FM1-43, FM4-64 and filipin to internodal cells of the green alga Chara corallina. Both FM dyes stained stable, long-living plasma membrane patches with a diameter of up to 1 microm. After 5 min, FM dyes labeled cortical, trembling structures up to 500 nm in size. ... More
Plasma membrane domains participate in pH banding of Chara internodal cells.
AuthorsSchmölzer PM, Höftberger M, Foissner I,
JournalPlant Cell Physiol
PubMed ID21659328
'We investigated the identity and distribution of cortical domains, stained by the endocytic marker FM 1-43, in branchlet internodal cells of the characean green algae Chara corallina and Chara braunii. Co-labeling with NBD C(6)-sphingomyelin, a plasma membrane dye, which is not internalized, confirmed their location in the plasma membrane, and ... More
Nucleoside diphosphate kinase, a source of GTP, is required for dynamin-dependent synaptic vesicle recycling.
AuthorsKrishnan KS, Rikhy R, Rao S, Shivalkar M, Mosko M, Narayanan R, Etter P, Estes PS, Ramaswami M
JournalNeuron
PubMed ID11343655
'Nucleoside diphosphate kinase (NDK), an enzyme encoded by the Drosophila abnormal wing discs (awd) or human nm23 tumor suppressor genes, generates nucleoside triphosphates from respective diphosphates. We demonstrate that NDK regulates synaptic vesicle internalization at the stage where function of the dynamin GTPase is required. awd mutations lower the temperature ... More
Tracing surfactant transformation from cellular release to insertion into an air-liquid interface.
AuthorsHaller T, Dietl P, Stockner H, Frick M, Mair N, Tinhofer I, Ritsch A, Enhorning G, Putz G
JournalAm J Physiol Lung Cell Mol Physiol
PubMed ID14704221
'Pulmonary surfactant is secreted by alveolar type II cells as lipid-rich, densely packed lamellar body-like particles (LBPs). The particulate nature of released LBPs might be the result of structural and/or thermodynamic forces. Thus mechanisms must exist that promote their transformation into functional units. To further define these mechanisms, we developed ... More
An incremental approach to automated protein localisation.
AuthorsTscherepanow M, Jensen N, Kummert F,
JournalBMC Bioinformatics
PubMed ID18937856
'BACKGROUND: The subcellular localisation of proteins in intact living cells is an important means for gaining information about protein functions. Even dynamic processes can be captured, which can barely be predicted based on amino acid sequences. Besides increasing our knowledge about intracellular processes, this information facilitates the development of innovative ... More
Visualization of myoglobin-facilitated mitochondrial O(2) delivery in a single isolated cardiomyocyte.
AuthorsTakahashi E, Endoh H, Doi K
JournalBiophys J
PubMed ID10828001
'The purpose of the present study was to visualize myoglobin-facilitated oxygen delivery to mitochondria at a critical mitochondrial oxygen supply in single isolated cardiomyocytes of rats. Using the autofluorescence of mitochondrial reduced nicotinamide adenine dinucleotide (phosphate) (NAD(P)H), the mitochondrial oxygen supply was imaged from approximately 1.4 microm inside the cell ... More
The optically determined size of exo/endo cycling vesicle pool correlates with the quantal content at the neuromuscular junction of Drosophila larvae.
AuthorsKuromi H, Kidokoro Y
JournalJ Neurosci
PubMed ID10024343
'According to the current theory of synaptic transmission, the amplitude of evoked synaptic potentials correlates with the number of synaptic vesicles released at the presynaptic terminals. Synaptic vesicles in presynaptic boutons constitute two distinct pools, namely, exo/endo cycling and reserve pools (). We defined the vesicles that were endocytosed and ... More
Paired-pulse depression of unitary quantal amplitude at single hippocampal synapses.
AuthorsChen G, Harata NC, Tsien RW
JournalProc Natl Acad Sci U S A
PubMed ID14722357
'At central synapses, quantal size is generally regarded as fluctuating around a fixed mean with little change during short-term synaptic plasticity. We evoked quantal release by brief electric stimulation at single synapses visualized with FM 1-43 dye in hippocampal cultures. The majority of quantal events evoked at single synapses were ... More
Exocytosis in alveolar type II cells revealed by cell capacitance and fluorescence measurements.
AuthorsMair N, Haller T, Dietl P
JournalAm J Physiol
PubMed ID9950901
'Measurement of lamellar body (LB) exocytosis at high spatial and temporal resolution was recently enabled by fluorescence of the dye FM 1-43 (FFM1-43). Here, the capabilities of this method were further examined and extended by simultaneous measurement of the cell membrane capacitance (Cm) and laser-scanning confocal microscopy. Step increases in ... More
Caspase dependence of target cell damage induced by cytotoxic lymphocytes.
AuthorsSarin A, Haddad EK, Henkart PA
JournalJ Immunol
PubMed ID9743340
'Since the CTL secreted granule protease granzyme B can activate multiple target caspases, it has been proposed that this pathway is responsible for CTL-induced cytolysis of Fas-negative targets. However, target lysis via the granule exocytosis pathway is completely resistant to caspase inhibitors. To test the possibility that granzymes trigger a ... More
Fluorescence microscopy of calcium and synaptic vesicle dynamics during synapse formation in tissue culture.
AuthorsDai Z, Peng HB
JournalHistochem J
PubMed ID10188926
'The signal transduction process involved in the development of the nerve terminal is an intriguing question in developmental neurobiology. During the formation of the neuromuscular junction, presynaptic development is induced by growth cone''s contact with the target muscle cell. Fluorescence microscopy with specific markers has made it possible to follow ... More
Intracellular movements of fluorescently labeled synaptic vesicles in frog motor nerve terminals during nerve stimulation.
AuthorsBetz WJ, Bewick GS, Ridge RM
JournalNeuron
PubMed ID1418996
'We stained synaptic vesicles in frog motor nerve terminals with FM1-43 and studied changes in the shape and position of vesicle clusters during nerve stimulation. Each stained vesicle cluster appeared as a fluorescent spot. During repetitive nerve stimulation the spots gradually dimmed, most without changing shape or position. Occasionally, however, ... More
Fluorescent probes for living cells.
AuthorsJohnson I
JournalHistochem J
PubMed ID10188922
'The functional characteristics of fluorescent probes used for imaging and measuring dynamic processes in living cells are reviewed. Initial consideration is given to general design requirements for delivery, targeting, detectability and fluorescence readout, and current technologies for attaining them. Discussion then proceeds to the more application-specific properties of intracellular ion ... More
A role for actin dynamics in individualization during spermatogenesis in Drosophila melanogaster.
AuthorsNoguchi T, Miller KG
JournalDevelopment
PubMed ID12642486
'In order to better understand the mechanism of sperm individualization during spermatogenesis in Drosophila melanogaster, we have developed an in vitro culture system in which we can perform live observation of individualization in isolated cysts. The whole process of individualization, during which a bundle of 64 syncytial spermatids is separated ... More
Membrane changes associated with secretion occur in the absence of external calcium or after treatment with cytoskeletal disrupting agents.
AuthorsStafford SV, Schofield JG
JournalBiochem Soc Trans
PubMed ID7958208
Fluorescent high-throughput screening of chemical inducers of neuronal differentiation in skeletal muscle cells.
AuthorsWilliams DR, Kim GH, Lee MR, Shin I,
JournalNat Protoc
PubMed ID18451791
'This protocol describes detailed procedures for the fluorescent high-throughput screening of small molecules that induce neurogenesis in cultures of skeletal muscle cells. The detection of neurogenesis relies on a fluorescent dye, FM 1-43, which is used to study the neuronal property of depolarization-induced synaptic vesicle recycling. Thus, small molecules with ... More
Estrogen enhances depolarization-induced glutamate release through activation of phosphatidylinositol 3-kinase and mitogen-activated protein kinase in cultured hippocampal neurons.
AuthorsYokomaku D, Numakawa T, Numakawa Y, Suzuki S, Matsumoto T, Adachi N, Nishio C, Taguchi T, Hatanaka H
JournalMol Endocrinol
PubMed ID12554763
'Changes in synaptic efficacy are considered necessary for learning and memory. Recently, it has been suggested that estrogen controls synaptic function in the central nervous system. However, it is unclear how estrogen regulates synaptic function in central nervous system neurons. We found that estrogen potentiated presynaptic function in cultured hippocampal ... More
Structure and functional connections of presynaptic terminals in the vertebrate retina revealed by activity-dependent dyes and confocal microscopy.
'The fluorescent dyes sulforhodamine 101 (SR 101) and FM1-43 were used as activity-dependent dyes (ADDs) to label presynaptic terminals in the retinas of a broad range of animals, including amphibians, mammals, fish, and turtles. The pattern of dye uptake was studied in live retinal preparations by using brightfield, fluorescence, and ... More
Visualization of synaptic activity in hippocampal slices with FM1-43 enabled by fluorescence quenching.
AuthorsPyle JL, Kavalali ET, Choi S, Tsien RW
JournalNeuron
PubMed ID10624944
'Fluorescence imaging of presynaptic uptake and release of styryl dyes such as FM1-43 has provided valuable insights into synaptic function. However, in studies of CNS neurons, the utility of these dyes has been severely limited by nonsynaptic background fluorescence. This has thwarted the use of FM dyes in systems more ... More
alpha-Latrotoxin releases calcium in frog motor nerve terminals.
AuthorsTsang CW, Elrick DB, Charlton MP
JournalJ Neurosci
PubMed ID11102474
'alpha-Latrotoxin (alpha-LTX) is a neurotoxin that accelerates spontaneous exocytosis independently of extracellular Ca(2+). Although alpha-LTX increases spontaneous transmitter release at synapses, the mechanism is unknown. We tested the hypothesis that alpha-LTX causes transmitter release by mobilizing intracellular Ca(2+) in frog motor nerve terminals. Transmitter release was measured electrophysiologically and with ... More
Two-photon imaging of spontaneous vesicular release in acute brain slices and its modulation by presynaptic GABAA receptors.
AuthorsAxmacher N, Winterer J, Stanton PK, Draguhn A, Müller W
JournalNeuroimage
PubMed ID15193633
'Action potential-independent spontaneous vesicular release of gamma-aminobutyric acid (GABA) in the CNS mediates miniature inhibitory postsynaptic currents (mIPSCs) and exerts an important control on central excitability. Using dual-photon laser scan microscopy and hyperosmotic loading of the readily releasable vesicle pool with the fluorescent styryl dye FM1-43 in hippocampal slice, we ... More
Single synaptic vesicle tracking in individual hippocampal boutons at rest and during synaptic activity.
AuthorsLemke EA, Klingauf J
JournalJ Neurosci
PubMed ID16306416
'How synaptic vesicles move within central nervous synapses to their docking sites at the plasma membrane is widely discussed in synaptic physiology. This question is especially difficult to investigate in the small hippocampal boutons, which themselves can slowly move during observation in primary cell culture. Here, we describe a single ... More
Actin has a molecular scaffolding, not propulsive, role in presynaptic function.
AuthorsSankaranarayanan S, Atluri PP, Ryan TA
JournalNat Neurosci
PubMed ID12536209
'We used actin tagged with enhanced green fluorescent protein (EGFP-actin) to characterize the distribution and dynamics of actin in living presynaptic terminals in rat CNS neurons. Actin was preferentially concentrated around--and appeared to surround--the presynaptic vesicle cluster. In resting terminals, approximately 30% of actin was found to be in a ... More
'Vertebrate mechanosensory hair cells contain a narrow "pericuticular" zone which is densely populated with small vesicles between the cuticular plate and cellular junctions near the apical surface. The presence of many cytoplasmic vesicles suggests that the apical surface of hair cells has a high turnover rate. The significance of intense ... More
Monitoring clathrin-mediated endocytosis during synaptic activity.
AuthorsMueller VJ, Wienisch M, Nehring RB, Klingauf J
JournalJ Neurosci
PubMed ID14985443
'To visualize clathrin redistribution during endocytosis in hippocampal boutons, we used a fusion protein of clathrin light chain with enhanced green fluorescent protein. Both high potassium and electric field stimulation lead after a stimulus-dependent delay to a transient increase of fluorescence in synapses, but a slight and transient decrease in ... More
Rapid insulin-induced exocytosis in white rat adipocytes.
AuthorsChowdhury HH, Kreft M, Zorec R
JournalPflugers Arch
PubMed ID12466937
'Insulin is believed to increase glucose permeability of adipocytes by regulating the incorporation of glucose transporters into the plasma membrane by exocytosis. This process involves fusion of membrane-bound cellular compartments with the plasma membrane, thus influencing the plasma membrane area. However, insulin-induced changes in plasma membrane area have not yet ... More