Mitochondrial modulation of Ca2+ -induced Ca2+ -release in rat sensory neurons.
AuthorsJackson JG, Thayer SA
JournalJ Neurophysiol
PubMed ID16760347
'Ca2+ -induced Ca2+ -release (CICR) from ryanodine-sensitive Ca2+ stores provides a mechanism to amplify and propagate a transient increase in intracellular calcium concentration ([Ca2+]i). A subset of rat dorsal root ganglion neurons in culture exhibited regenerative CICR when sensitized by caffeine. [Ca2+]i oscillated in the maintained presence of 5 mM ... More
Selective, high-resolution fluorescence imaging of mitochondrial Ca2+ concentration.
AuthorsGerencsér AA AA, Adam-Vizi V
JournalCell Calcium
PubMed ID11733937
'We have developed a digital image processing technique based on highpass filtering of microfluorimetric images for selective transmission of fine image details corresponding to mitochondria. This technique enabled the detection of the mitochondrial calcium signals with high selectivity, simultaneously with the cytosolic calcium signal. The validity of this technique was ... More
Use of fluorescent Ca2+ dyes with green fluorescent protein and its variants: problems and solutions.
AuthorsBolsover S, Ibrahim O, O'luanaigh N, Williams H, Cockcroft S
JournalBiochem J
PubMed ID11368760
'We have studied the degree to which fluorescent Ca(2+) indicator dyes, and green fluorescent protein and its variants, can be used together. We find that the most commonly used fluorescent protein, enhanced green fluorescent protein (EGFP), seriously contaminates fura 2 signals. We suggest two alternative combinations for which there is ... More
CXCR4 regulates growth of both primary and metastatic breast cancer.
AuthorsSmith MC, Luker KE, Garbow JR, Prior JL, Jackson E, Piwnica-Worms D, Luker GD
JournalCancer Res
PubMed ID15574767
'The chemokine receptor CXCR4 and its cognate ligand CXCL12 recently have been proposed to regulate the directional trafficking and invasion of breast cancer cells to sites of metastases. However, effects of CXCR4 on the growth of primary breast cancer tumors and established metastases and survival have not been determined. We ... More
A novel method for assessing effects of hydrostatic fluid pressure on intracellular calcium: a study with bovine articular chondrocytes.
AuthorsMizuno S
JournalAm J Physiol Cell Physiol
PubMed ID15643052
'Chondrocytes in articular cartilage are exposed to hydrostatic pressure and distortional stress during weight bearing and joint loading. Because these stresses occur simultaneously in articular cartilage, the mechanism of mechanosignal transduction due to hydrostatic pressure alone in chondrocytes is not clear. In this study, we attempted to characterize the change ... More
Extrusion of Ca2+ from mouse motor terminal mitochondria via a Na+-Ca2+ exchanger increases post-tetanic evoked release.
AuthorsGarcía-Chacón LE, Nguyen KT, David G, Barrett EF
JournalJ Physiol
PubMed ID16613870
'Mitochondria sequester much of the Ca2+ that enters motor nerve terminals during repetitive stimulation at frequencies exceeding 10-20 Hz. We studied the post-stimulation extrusion of Ca2+ from mitochondria by measuring changes in matrix [Ca2+] with fluorescent indicators loaded into motor terminal mitochondria in the mouse levator auris longus muscle. Trains ... More
The Psi(m) depolarization that accompanies mitochondrial Ca2+ uptake is greater in mutant SOD1 than in wild-type mouse motor terminals.
AuthorsNguyen KT, García-Chacón LE, Barrett JN, Barrett EF, David G,
JournalProc Natl Acad Sci U S A
PubMed ID19174508
'The electrical gradient across the mitochondrial inner membrane (Psi(m)) is established by electron transport chain (ETC) activity and permits mitochondrial Ca(2+) sequestration. Using rhodamine-123, we determined how repetitive nerve stimulation (100 Hz) affects Psi(m) in motor terminals innervating mouse levator auris muscles. Stimulation-induced Psi(m) depolarizations in wild-type (WT) terminals were ... More
Complex interplay between glutamate receptors and intracellular Ca2+ stores during ischaemia in rat spinal cord white matter.
AuthorsOuardouz M, Malek S, Coderre E, Stys PK
JournalJ Physiol
PubMed ID16945971
'Electrophysiological recordings of propagated compound action potentials (CAPs) and axonal Ca(2+) measurements using confocal microscopy were used to study the interplay between AMPA receptors and intracellullar Ca(2+) stores in rat spinal dorsal columns subjected to in vitro combined oxygen and glucose deprivation (OGD). Removal of Ca(2+) or Na(+) from the ... More
Epigenetic Regulation of the Electrophysiological Phenotype of Human Embryonic Stem Cell-Derived Ventricular Cardiomyocytes: Insights for Driven Maturation and Hypertrophic Growth.
AuthorsChow MZ, Geng L, Kong CW, Keung W, Fung JC, Boheler KR, Li RA,
JournalStem Cells Dev
PubMed ID23656529
'Epigenetic regulation is implicated in embryonic development and the control of gene expression in a cell-specific manner. However, little is known about the role of histone methylation changes on human cardiac differentiation and maturation. Using human embryonic stem cells (hESCs) and their derived ventricular (V) cardiomyocytes (CMs) as a model, ... More
Real-time measurement of free Ca2+ changes in CNS myelin by two-photon microscopy.
AuthorsMicu I, Ridsdale A, Zhang L, Woulfe J, McClintock J, Brantner CA, Andrews SB, Stys PK
JournalNat Med
PubMed ID17603496
'Here we describe a technique for measuring changes in Ca2+ in the cytosolic domain of mature compact myelin of live axons in the central nervous system (CNS). We label the myelin sheath of optic nerve and dorsal column axons by using the Ca2+ indicator X-rhod-1 coupled with DiOC6(3) to produce ... More
Retinal glial (Müller ) cells: sensing and responding to tissue stretch.
AuthorsLindqvist N, Liu Q, Zajadacz J, Franze K, Reichenbach A,
JournalInvest Ophthalmol Vis Sci
PubMed ID19892866
'To test whether Müller glial cells sense, and respond to, mechanical tension in the retina. A device was designed to stretch the retina at right angles to its surface, across retinal layers. Pieces of retina were mounted between two hollow tubes, and uniaxial force was applied to the tissue using ... More
'Our understanding of the underlying mechanisms of Ca2+ signaling as well as our appreciation for its ubiquitous role in cellular processes has been rapidly advanced, in large part, due to the development of fluorescent Ca2+ indicators. In this chapter, we discuss some of the most common chemical Ca2+ indicators that ... More
Confocal Ca2+ imaging of organelles, cells, tissues, and organs.
AuthorsWilliams DA, Bowser DN, Petrou S
JournalMethods Enzymol
PubMed ID10506988
Imaging mitochondrial calcium signalling with fluorescent probes and single or two photon confocal microscopy.
AuthorsDavidson SM, Duchen MR,
JournalMethods Mol Biol
PubMed ID22057570
The concentration of calcium ions in the mitochondria has a profound impact on mitochondrial function, modulating respiratory activity at physiological concentrations, while causing lethal damage during calcium overload. The ... More
Predicting and avoiding subcellular compartmentalization artifacts arising from acetoxymethyl ester calcium imaging probes. The case of fluo-3 AM and a general account of the phenomenon including a problem avoidance chart.
AuthorsThompson K, Dockery P, Horobin RW,
JournalBiotech Histochem
PubMed ID22984940
Stimulated by difficulties experienced when using fluo-3 AM, we developed a general mechanistic model to aid understanding and practical application of calcium probes applied as acetoxymethyl (AM) esters. Several practical issues previously overlooked or under-emphasized are considered by this model. First, some AM ester probes are ... More
Ca2+ microfluorimetry in retinal Müller glial cells.
AuthorsWurm A, Pannicke T, Reichenbach A,
JournalMethods Mol Biol
PubMed ID23150374
Calcium acts as a prominent second messenger in virtually every cell type and modulates a plethora of cell functions. Thus, Ca(2+) microfluorimetry became a valuable tool to assess information about mechanisms involved in the regulation of the intracellular calcium level in research on living tissues. Here we offer insight into ... More
Assessing mitochondrial potential, calcium, and redox state in isolated mammalian cells using confocal microscopy.
AuthorsDavidson SM, Yellon D, Duchen MR,
JournalMethods Mol Biol
PubMed ID18314743
Mitochondria play a vital role in the regulation of intracellular calcium dynamics. Fluorescent dyes can be used to provide a direct measurement of the redox state, mitochondrial membrane potential, and mitochondrial calcium content. The simplicity of this approach lends itself to high-throughput assays and time-resolved analyses; however, care must be ... More
Lateral diffusion of Toll-like receptors reveals that they are transiently confined within lipid rafts on the plasma membrane.
AuthorsTriantafilou M, Morath S, Mackie A, Hartung T, Triantafilou K
JournalJ Cell Sci
PubMed ID15286178
The innate immune system utilises pattern recognition receptors in order to recognise microbial conserved molecular patterns. The family of Toll-like receptors (TLRs) has been shown to act as the main pattern recognition receptors for the innate immune system. Using biochemical as well as fluorescence imaging techniques, TLR2 and TLR4 were ... More
A transient receptor potential channel expressed in taste receptor cells.
AuthorsPérez CA, Huang L, Rong M, Kozak JA, Preuss AK, Zhang H, Max M, Margolskee RF
JournalNat Neurosci
PubMed ID12368808
We used differential screening of cDNAs from individual taste receptor cells to identify candidate taste transduction elements in mice. Among the differentially expressed clones, one encoded Trpm5, a member of the mammalian family of transient receptor potential (TRP) channels. We found Trpm5 to be expressed in a restricted manner, with ... More
Role of polyhydroxybutyrate in mitochondrial calcium uptake.
AuthorsSmithen M, Elustondo PA, Winkfein R, Zakharian E, Abramov AY, Pavlov E,
Journal
PubMed ID23702223
Polyhydroxybutyrate (PHB) is a biological polymer which belongs to the class of polyesters and is ubiquitously present in all living organisms. Mammalian mitochondrial membranes contain PHB consisting of up to 120 hydroxybutyrate residues. Roles played by PHB in mammalian mitochondria remain obscure. It was previously demonstrated that PHB of the ... More
Evidence for Ca(2+)-regulated ATP release in gastrointestinal stromal tumors.
AuthorsBerglund E, Berglund D, Akcakaya P, Ghaderi M, Daré E, Berggren PO, Köhler M, Aspinwall CA, Lui WO, Zedenius J, Larsson C, Bränström R,
JournalExp Cell Res
PubMed ID23499741
Gastrointestinal stromal tumors (GISTs) are thought to originate from the electrically active pacemaker cells of the gastrointestinal tract. Despite the presence of synaptic-like vesicles and proteins involved in cell secretion it remains unclear whether GIST cells possess regulated release mechanisms. The GIST tumor cell line GIST882 was used as a ... More
Necrosis is a form of cell death characterized by cytoplasmic and organelle swelling, compromised -membrane integrity, intracellular acidification, and increased levels of reactive oxygen species (ROS) and cytosolic Ca(2+). In the Drosophila ovary, two distinct forms of cell death occur naturally. In response to starvation, caspase-dependent cell death occurs during ... More
Animal cells connected by nanotubes can be electrically coupled through interposed gap-junction channels.
AuthorsWang X, Veruki ML, Bukoreshtliev NV, Hartveit E, Gerdes HH,
JournalProc Natl Acad Sci U S A
PubMed ID20855598
Tunneling nanotubes (TNTs) are recently discovered conduits for a previously unrecognized form of cell-to-cell communication. These nanoscale, F-actin-containing membrane tubes connect cells over long distances and facilitate the intercellular exchange of small molecules and organelles. Using optical membrane-potential measurements combined with mechanical stimulation and whole-cell patch-clamp recording, we demonstrate that ... More
FM dyes enter via a store-operated calcium channel and modify calcium signaling of cultured astrocytes.
AuthorsLi D, Hérault K, Oheim M, Ropert N,
JournalProc Natl Acad Sci U S A
PubMed ID20007370
The amphiphilic fluorescent styryl pyridinium dyes FM1-43 and FM4-64 are used to probe activity-dependent synaptic vesicle cycling in neurons. Cultured astrocytes can internalize FM1-43 and FM4-64 inside vesicles but their uptake is insensitive to the elevation of cytosolic calcium (Ca(2+)) concentration and the underlying mechanism remains unclear. Here we used ... More
PINK1-associated Parkinson's disease is caused by neuronal vulnerability to calcium-induced cell death.
AuthorsGandhi S, Wood-Kaczmar A, Yao Z, Plun-Favreau H, Deas E, Klupsch K, Downward J, Latchman DS, Tabrizi SJ, Wood NW, Duchen MR, Abramov AY,
JournalMol Cell
PubMed ID19285945
Mutations in PINK1 cause autosomal recessive Parkinson's disease. PINK1 is a mitochondrial kinase of unknown function. We investigated calcium homeostasis and mitochondrial function in PINK1-deficient mammalian neurons. We demonstrate physiologically that PINK1 regulates calcium efflux from the mitochondria via the mitochondrial Na(+)/Ca(2+) exchanger. PINK1 deficiency causes mitochondrial accumulation of calcium, ... More
Delayed development of adult-generated granule cells in dentate gyrus.
A substantial fraction of adult-generated granule cells in the dentate gyrus survive and integrate into the existing neuronal network. These newborn neurons must navigate the environment of the adult brain, a setting that is presumably less optimized for neuronal maturation compared with that in the developing brain. We used EGFP ... More
Dynamic regulation of spine-dendrite coupling in cultured hippocampal neurons.
AuthorsKorkotian E, Holcman D, Segal M
JournalEur J Neurosci
PubMed ID15548208
We investigated the role of dendritic spine morphology in spine-dendrite calcium communication using novel experimental and theoretical approaches. A transient rise in [Ca2+]i was produced in individual spine heads of Fluo-4-loaded cultured hippocampal neurons by flash photolysis of caged calcium. Following flash photolysis in the spine head, a delayed [Ca2+]i ... More
To reveal heterogeneity of mitochondrial function on the single-mitochondrion level we have studied the spatiotemporal dynamics of the mitochondrial Ca2+ signaling and the mitochondrial membrane potential using wide-field fluorescence imaging and digital image processing techniques. Here we demonstrate first-time discrete sites--intramitochondrial hotspots--of Ca2+ uptake after Ca2+ release from intracellular stores, ... More
Bradykinin-induced nuclear factor of activated T-cells-dependent transcription in rat dorsal root ganglion neurons.
AuthorsJackson JG, Usachev YM, Thayer SA
JournalMol Pharmacol
PubMed ID17485565
Bradykinin produced at sites of tissue injury and inflammation elicits acute pain and alters the sensitivity of nociceptive neurons to subsequent stimuli. We tested the hypothesis that bradykinin could elicit long-lasting changes in nociceptor function by activating members of the nuclear factor of activated T-cells (NFAT) family of transcription factors. ... More
NMDA receptors mediate calcium accumulation in myelin during chemical ischaemia.
AuthorsMicu I, Jiang Q, Coderre E, Ridsdale A, Zhang L, Woulfe J, Yin X, Trapp BD, McRory JE, Rehak R, Zamponi GW, Wang W, Stys PK
JournalNature
PubMed ID16372019
Central nervous system myelin is a specialized structure produced by oligodendrocytes that ensheaths axons, allowing rapid and efficient saltatory conduction of action potentials. Many disorders promote damage to and eventual loss of the myelin sheath, which often results in significant neurological morbidity. However, little is known about the fundamental mechanisms ... More
Limited plasticity of mesenchymal stem cells cocultured with adult cardiomyocytes.
AuthorsGallo MP, Ramella R, Alloatti G, Penna C, Pagliaro P, Marcantoni A, Bonafé F, Losano G, Levi R
JournalJ Cell Biochem
PubMed ID16888800
In order to assess, in a controlled in vitro model, the differentiation potential of adult bone marrow derived stem cells we have developed a coculture procedure using adult rat cardiomyocytes and mesenchymal stem cells (MSCs) from transgenic GFP positive rats. We investigated in the cocultured MSCs the time course of ... More
A calcium-induced calcium influx factor, nitric oxide, modulates the refilling of calcium stores in astrocytes.
AuthorsLi N, Sul JY, Haydon PG
JournalJ Neurosci
PubMed ID14614089
The roles of nitric oxide are primarily undefined in astrocytes, cells that are active partners in synaptic transmission. Because nitric oxide synthases are present in astrocytes, we imaged the formation of nitric oxide in cultured murine cortical astrocytes using DAF-FM (4-amino-5-methylamino-2',7'-difluorofluorescein diacetate). We demonstrated that physiological concentrations of ATP induced ... More
P2Y1 receptor-evoked glutamate exocytosis from astrocytes: control by tumor necrosis factor-alpha and prostaglandins.
AuthorsDomercq M, Brambilla L, Pilati E, Marchaland J, Volterra A, Bezzi P
JournalJ Biol Chem
PubMed ID16882655
ATP, released by both neurons and glia, is an important mediator of brain intercellular communication. We find that selective activation of purinergic P2Y1 receptors (P2Y1R) in cultured astrocytes triggers glutamate release. By total internal fluorescence reflection imaging of fluorescence-labeled glutamatergic vesicles, we document that such release occurs by regulated exocytosis. ... More
Effects of laser polarization on responses of the fluorescent Ca2+ indicator X-Rhod-1 in neurons and myelin.
Authors
JournalNeurophotonics
PubMed ID28612034
Regulation of the Muscarinic M3 Receptor by Myocardin-Related Transcription Factors.
Authors
JournalFront Physiol
PubMed ID34539433
Optogenetic Inhibition of Gαq Protein Signaling Reduces Calcium Oscillation Stochasticity.
Authors
JournalACS Synth Biol
PubMed ID29792810
Oscillatory cortical forces promote three dimensional cell intercalations that shape the murine mandibular arch.
Authors
JournalNat Commun
PubMed ID30979871
Intravital quantification reveals dynamic calcium concentration changes across B cell differentiation stages.
Authors
JournalElife
PubMed ID33749591
Ca2+-Dependent Inactivation of GluN2A and GluN2B NMDA Receptors Occurs by a Common Kinetic Mechanism.
Authors
JournalBiophys J
PubMed ID31629478
Direct optogenetic stimulation of smooth muscle cells to control gastric contractility.