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Lawal TA, Wires ES, Terry NL, Dowling JJ, Todd JJ. Preclinical model systems of ryanodine receptor 1-related myopathies and malignant hyperthermia: a comprehensive scoping review of works published 1990-2019. Orphanet J Rare Dis 2020; 15:113. [PMID: 32381029 PMCID: PMC7204063 DOI: 10.1186/s13023-020-01384-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Accepted: 04/14/2020] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Pathogenic variations in the gene encoding the skeletal muscle ryanodine receptor (RyR1) are associated with malignant hyperthermia (MH) susceptibility, a life-threatening hypermetabolic condition and RYR1-related myopathies (RYR1-RM), a spectrum of rare neuromuscular disorders. In RYR1-RM, intracellular calcium dysregulation, post-translational modifications, and decreased protein expression lead to a heterogenous clinical presentation including proximal muscle weakness, contractures, scoliosis, respiratory insufficiency, and ophthalmoplegia. Preclinical model systems of RYR1-RM and MH have been developed to better understand underlying pathomechanisms and test potential therapeutics. METHODS We conducted a comprehensive scoping review of scientific literature pertaining to RYR1-RM and MH preclinical model systems in accordance with the PRISMA Scoping Reviews Checklist and the framework proposed by Arksey and O'Malley. Two major electronic databases (PubMed and EMBASE) were searched without language restriction for articles and abstracts published between January 1, 1990 and July 3, 2019. RESULTS Our search yielded 5049 publications from which 262 were included in this review. A majority of variants tested in RYR1 preclinical models were localized to established MH/central core disease (MH/CCD) hot spots. A total of 250 unique RYR1 variations were reported in human/rodent/porcine models with 95% being missense substitutions. The most frequently reported RYR1 variant was R614C/R615C (human/porcine total n = 39), followed by Y523S/Y524S (rabbit/mouse total n = 30), I4898T/I4897T/I4895T (human/rabbit/mouse total n = 20), and R163C/R165C (human/mouse total n = 18). The dyspedic mouse was utilized by 47% of publications in the rodent category and its RyR1-null (1B5) myotubes were transfected in 23% of publications in the cellular model category. In studies of transfected HEK-293 cells, 57% of RYR1 variations affected the RyR1 channel and activation core domain. A total of 15 RYR1 mutant mouse strains were identified of which ten were heterozygous, three were compound heterozygous, and a further two were knockout. Porcine, avian, zebrafish, C. elegans, canine, equine, and drosophila model systems were also reported. CONCLUSIONS Over the past 30 years, there were 262 publications on MH and RYR1-RM preclinical model systems featuring more than 200 unique RYR1 variations tested in a broad range of species. Findings from these studies have set the foundation for therapeutic development for MH and RYR1-RM.
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Affiliation(s)
- Tokunbor A Lawal
- National Institute of Nursing Research, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Emily S Wires
- National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD, USA
| | - Nancy L Terry
- National Institutes of Health Library, National Institutes of Health, Bethesda, MD, USA
| | - James J Dowling
- Program for Genetics and Genome Biology, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Joshua J Todd
- National Institute of Nursing Research, National Institutes of Health, Bethesda, MD, 20892, USA.
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Arias-Calderón M, Almarza G, Díaz-Vegas A, Contreras-Ferrat A, Valladares D, Casas M, Toledo H, Jaimovich E, Buvinic S. Characterization of a multiprotein complex involved in excitation-transcription coupling of skeletal muscle. Skelet Muscle 2016; 6:15. [PMID: 27069569 PMCID: PMC4827232 DOI: 10.1186/s13395-016-0087-5] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Accepted: 03/19/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Electrical activity regulates the expression of skeletal muscle genes by a process known as "excitation-transcription" (E-T) coupling. We have demonstrated that release of adenosine 5'-triphosphate (ATP) during depolarization activates membrane P2X/P2Y receptors, being the fundamental mediators between electrical stimulation, slow intracellular calcium transients, and gene expression. We propose that this signaling pathway would require the proper coordination between the voltage sensor (dihydropyridine receptor, DHPR), pannexin 1 channels (Panx1, ATP release conduit), nucleotide receptors, and other signaling molecules. The goal of this study was to assess protein-protein interactions within the E-T machinery and to look for novel constituents in order to characterize the signaling complex. METHODS Newborn derived myotubes, adult fibers, or triad fractions from rat or mouse skeletal muscles were used. Co-immunoprecipitation, 2D blue native SDS/PAGE, confocal microscopy z-axis reconstruction, and proximity ligation assays were combined to assess the physical proximity of the putative complex interactors. An L6 cell line overexpressing Panx1 (L6-Panx1) was developed to study the influence of some of the complex interactors in modulation of gene expression. RESULTS Panx1, DHPR, P2Y2 receptor (P2Y2R), and dystrophin co-immunoprecipitated in the different preparations assessed. 2D blue native SDS/PAGE showed that DHPR, Panx1, P2Y2R and caveolin-3 (Cav3) belong to the same multiprotein complex. We observed co-localization and protein-protein proximity between DHPR, Panx1, P2Y2R, and Cav3 in adult fibers and in the L6-Panx1 cell line. We found a very restricted location of Panx1 and Cav3 in a putative T-tubule zone near the sarcolemma, while DHPR was highly expressed all along the transverse (T)-tubule. By Panx1 overexpression, extracellular ATP levels were increased both at rest and after electrical stimulation. Basal mRNA levels of the early gene cfos and the oxidative metabolism markers citrate synthase and peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1α) were significantly increased by Panx1 overexpression. Interleukin 6 expression evoked by 20-Hz electrical stimulation (270 pulses, 0.3 ms each) was also significantly upregulated in L6-Panx1 cells. CONCLUSIONS We propose the existence of a relevant multiprotein complex that coordinates events involved in E-T coupling. Unveiling the molecular actors involved in the regulation of gene expression will contribute to the understanding and treatment of skeletal muscle disorders due to wrong-expressed proteins, as well as to improve skeletal muscle performance.
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MESH Headings
- Adenosine Triphosphate/metabolism
- Animals
- Animals, Newborn
- Calcium Channels, L-Type/genetics
- Calcium Channels, L-Type/metabolism
- Caveolin 3/genetics
- Caveolin 3/metabolism
- Cell Line
- Connexins/genetics
- Connexins/metabolism
- Dystrophin/genetics
- Dystrophin/metabolism
- Electric Stimulation
- Gene Expression Regulation
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Multiprotein Complexes
- Muscle Contraction
- Muscle Fibers, Skeletal/metabolism
- Muscle Proteins/genetics
- Muscle Proteins/metabolism
- Nerve Tissue Proteins/genetics
- Nerve Tissue Proteins/metabolism
- Protein Binding
- Rats, Wistar
- Receptors, Purinergic P2Y2/genetics
- Receptors, Purinergic P2Y2/metabolism
- Transcription, Genetic
- Transcriptional Activation
- Transfection
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Affiliation(s)
- Manuel Arias-Calderón
- />Centro de Estudios Moleculares de la Célula, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, 8380453 Chile
- />Instituto de Investigación en Ciencias Odontológicas, Facultad de Odontología, Universidad de Chile, Sergio Livingstone Pohlhammer 943, 8380492 Santiago, Chile
| | - Gonzalo Almarza
- />Centro de Estudios Moleculares de la Célula, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, 8380453 Chile
| | - Alexis Díaz-Vegas
- />Centro de Estudios Moleculares de la Célula, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, 8380453 Chile
| | - Ariel Contreras-Ferrat
- />Centro de Estudios Moleculares de la Célula, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, 8380453 Chile
| | - Denisse Valladares
- />Centro de Estudios Moleculares de la Célula, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, 8380453 Chile
| | - Mariana Casas
- />Centro de Estudios Moleculares de la Célula, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, 8380453 Chile
| | - Héctor Toledo
- />Programa de Biología Molecular y Celular, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, 8380453 Chile
| | - Enrique Jaimovich
- />Centro de Estudios Moleculares de la Célula, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, 8380453 Chile
- />Programa de Biología Molecular y Celular, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, 8380453 Chile
| | - Sonja Buvinic
- />Instituto de Investigación en Ciencias Odontológicas, Facultad de Odontología, Universidad de Chile, Sergio Livingstone Pohlhammer 943, 8380492 Santiago, Chile
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Filipova D, Walter AM, Gaspar JA, Brunn A, Linde NF, Ardestani MA, Deckert M, Hescheler J, Pfitzer G, Sachinidis A, Papadopoulos S. Gene profiling of embryonic skeletal muscle lacking type I ryanodine receptor Ca(2+) release channel. Sci Rep 2016; 6:20050. [PMID: 26831464 PMCID: PMC4735524 DOI: 10.1038/srep20050] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Accepted: 12/22/2015] [Indexed: 12/20/2022] Open
Abstract
In mature skeletal muscle, the intracellular Ca2+ concentration rises dramatically upon membrane depolarization, constituting the link between excitation and contraction. This process requires Ca2+ release from the sarcoplasmic reticulum via the type 1 ryanodine receptor (RYR1). However, RYR1’s potential roles in muscle development remain obscure. We used an established RyR1- null mouse model, dyspedic, to investigate the effects of the absence of a functional RYR1 and, consequently, the lack of RyR1-mediated Ca2+ signaling, during embryogenesis. Homozygous dyspedic mice die after birth and display small limbs and abnormal skeletal muscle organization. Skeletal muscles from front and hind limbs of dyspedic fetuses (day E18.5) were subjected to microarray analyses, revealing 318 differentially expressed genes. We observed altered expression of multiple transcription factors and members of key signaling pathways. Differential regulation was also observed for genes encoding contractile as well as muscle-specific structural proteins. Additional qRT-PCR analysis revealed altered mRNA levels of the canonical muscle regulatory factors Six1, Six4, Pax7, MyoD, MyoG and MRF4 in mutant muscle, which is in line with the severe developmental retardation seen in dyspedic muscle histology analyses. Taken together, these findings suggest an important non-contractile role of RyR1 or RYR1-mediated Ca2+ signaling during muscle organ development.
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Affiliation(s)
- Dilyana Filipova
- Center of Physiology and Pathophysiology, Institute of Vegetative Physiology, Medical Faculty of the University of Cologne, Robert-Koch-Str. 39, Cologne 50931, Germany
| | - Anna M Walter
- Center of Physiology and Pathophysiology, Institute of Vegetative Physiology, Medical Faculty of the University of Cologne, Robert-Koch-Str. 39, Cologne 50931, Germany
| | - John A Gaspar
- Center of Physiology and Pathophysiology, Institute of Neurophysiology, Medical Faculty of the University of Cologne, Robert-Koch-Str. 39, Cologne 50931, Germany
| | - Anna Brunn
- Department of Neuropathology, University Hospital of Cologne, Cologne, Germany
| | - Nina F Linde
- Center of Physiology and Pathophysiology, Institute of Vegetative Physiology, Medical Faculty of the University of Cologne, Robert-Koch-Str. 39, Cologne 50931, Germany
| | - Mostafa A Ardestani
- Center of Physiology and Pathophysiology, Institute of Vegetative Physiology, Medical Faculty of the University of Cologne, Robert-Koch-Str. 39, Cologne 50931, Germany
| | - Martina Deckert
- Department of Neuropathology, University Hospital of Cologne, Cologne, Germany
| | - Jürgen Hescheler
- Center of Physiology and Pathophysiology, Institute of Neurophysiology, Medical Faculty of the University of Cologne, Robert-Koch-Str. 39, Cologne 50931, Germany
| | - Gabriele Pfitzer
- Center of Physiology and Pathophysiology, Institute of Vegetative Physiology, Medical Faculty of the University of Cologne, Robert-Koch-Str. 39, Cologne 50931, Germany
| | - Agapios Sachinidis
- Center of Physiology and Pathophysiology, Institute of Neurophysiology, Medical Faculty of the University of Cologne, Robert-Koch-Str. 39, Cologne 50931, Germany
| | - Symeon Papadopoulos
- Center of Physiology and Pathophysiology, Institute of Vegetative Physiology, Medical Faculty of the University of Cologne, Robert-Koch-Str. 39, Cologne 50931, Germany
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Phosphoinositides in Ca(2+) signaling and excitation-contraction coupling in skeletal muscle: an old player and newcomers. J Muscle Res Cell Motil 2015; 36:491-9. [PMID: 26377756 DOI: 10.1007/s10974-015-9422-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Accepted: 09/09/2015] [Indexed: 10/23/2022]
Abstract
Since the postulate, 30 years ago, that phosphatidylinositol 4,5-bisphosphate (PtdIns(4,5)P 2) as the precursor of inositol 1,4,5-trisphosphate (Ins(1,4,5)P 3) would be critical for skeletal muscle excitation-contraction (EC) coupling, the issue of whether phosphoinositides (PtdInsPs) may have something to do with Ca(2+) signaling in muscle raised limited interest, if any. In recent years however, the PtdInsP world has expanded considerably with new functions for PtdIns(4,5)P 2 but also with functions for the other members of the PtdInsP family. In this context, the discovery that genetic deficiency in a PtdInsP phosphatase has dramatic consequences on Ca(2+) homeostasis in skeletal muscle came unanticipated and opened up new perspectives in regards to how PtdInsPs modulate muscle Ca(2+) signaling under normal and disease conditions. This review intends to make an update of the established, the questioned, and the unknown regarding the role of PtdInsPs in skeletal muscle Ca(2+) homeostasis and EC coupling, with very specific emphasis given to Ca(2+) signals in differentiated skeletal muscle fibers.
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Xie W, Wang JQ, Wang QC, Wang Y, Yao S, Tang TS. Adult neural progenitor cells from Huntington's disease mouse brain exhibit increased proliferation and migration due to enhanced calcium and ROS signals. Cell Prolif 2015; 48:517-31. [PMID: 26269226 DOI: 10.1111/cpr.12205] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Accepted: 06/10/2015] [Indexed: 12/20/2022] Open
Abstract
OBJECTIVES Huntington's disease (HD) is an inherited human neurodegenerative disorder characterized by uncontrollable movement, psychiatric disturbance and cognitive decline. Impaired proliferative/differentiational potentials of adult neural progenitor cells (ANPCs) have been thought to be a pathogenic mechanism involved in it. In this study, we aimed to elucidate intrinsic properties of ANPCs subjected to neurodegenerative condition in YAC128 HD mice. MATERIALS AND METHODS ANPCs were isolated from the SVZ regions of 4-month-old WT and YAC128 mice. Cell proliferation, migration and neuronal differentiation in vitro were compared between these two genotypes with/without Ca(2+) inhibitors or ROS scavenger treatments. Differences in ANPC proliferation and differentiation capabilities in vivo between the two genotypes were evaluated using Ki-67 and Doublecortin (DCX) immunofluorescence respectively. RESULTS Compared to WT ANPCs, YAC128 ANPCs had significantly enhanced cell proliferation, migration and neuronal differentiation in vitro, accompanied by increased Ca(2+) and ROS signals. Raised proliferation and migration in YAC128 ANPCs were abolished by Ca(2+) signalling antagonists and ROS scavenging. However, in vivo, HD ANPCs failed to show any elevated proliferation or differentiation. CONCLUSIONS Increased Ca(2+) signalling and higher level of ROS conferred HD ANPC enhancement of proliferation and migration potentials. However, the in vivo micro-environment did not support endogenous ANPCs to respond appropriately to neuronal loss in these YAC128 mouse brains.
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Affiliation(s)
- Wenjuan Xie
- State Key Laboratory of Biomembrane and Membrane Biotechnology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Jiu-Qiang Wang
- State Key Laboratory of Biomembrane and Membrane Biotechnology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Qiao-Chu Wang
- State Key Laboratory of Biomembrane and Membrane Biotechnology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Yun Wang
- State Key Laboratory of Biomembrane and Membrane Biotechnology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Sheng Yao
- Department of Neurology, Navy General Hospital, Beijing, 100048, China
| | - Tie-Shan Tang
- State Key Laboratory of Biomembrane and Membrane Biotechnology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
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6
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O-Uchi J, Jhun BS, Hurst S, Bisetto S, Gross P, Chen M, Kettlewell S, Park J, Oyamada H, Smith GL, Murayama T, Sheu SS. Overexpression of ryanodine receptor type 1 enhances mitochondrial fragmentation and Ca2+-induced ATP production in cardiac H9c2 myoblasts. Am J Physiol Heart Circ Physiol 2013; 305:H1736-51. [PMID: 24124188 DOI: 10.1152/ajpheart.00094.2013] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Ca(+) influx to mitochondria is an important trigger for both mitochondrial dynamics and ATP generation in various cell types, including cardiac cells. Mitochondrial Ca(2+) influx is mainly mediated by the mitochondrial Ca(2+) uniporter (MCU). Growing evidence also indicates that mitochondrial Ca(2+) influx mechanisms are regulated not solely by MCU but also by multiple channels/transporters. We have previously reported that skeletal muscle-type ryanodine receptor (RyR) type 1 (RyR1), which expressed at the mitochondrial inner membrane, serves as an additional Ca(2+) uptake pathway in cardiomyocytes. However, it is still unclear which mitochondrial Ca(2+) influx mechanism is the dominant regulator of mitochondrial morphology/dynamics and energetics in cardiomyocytes. To investigate the role of mitochondrial RyR1 in the regulation of mitochondrial morphology/function in cardiac cells, RyR1 was transiently or stably overexpressed in cardiac H9c2 myoblasts. We found that overexpressed RyR1 was partially localized in mitochondria as observed using both immunoblots of mitochondrial fractionation and confocal microscopy, whereas RyR2, the main RyR isoform in the cardiac sarcoplasmic reticulum, did not show any expression at mitochondria. Interestingly, overexpression of RyR1 but not MCU or RyR2 resulted in mitochondrial fragmentation. These fragmented mitochondria showed bigger and sustained mitochondrial Ca(2+) transients compared with basal tubular mitochondria. In addition, RyR1-overexpressing cells had a higher mitochondrial ATP concentration under basal conditions and showed more ATP production in response to cytosolic Ca(2+) elevation compared with nontransfected cells as observed by a matrix-targeted ATP biosensor. These results indicate that RyR1 possesses a mitochondrial targeting/retention signal and modulates mitochondrial morphology and Ca(2+)-induced ATP production in cardiac H9c2 myoblasts.
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Affiliation(s)
- Jin O-Uchi
- Center for Translational Medicine, Department of Medicine, Jefferson Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania
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Shang Y, Chen L, Liu Z, Wang X, Ma X, Miao L. Cytosolic Ca(2+) as a multifunctional modulator is required for spermiogenesis in Ascaris suum. Protein Cell 2013; 4:456-66. [PMID: 23686736 DOI: 10.1007/s13238-013-3019-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Accepted: 04/07/2013] [Indexed: 10/26/2022] Open
Abstract
The dynamic polar polymers actin filaments and microtubules are usually employed to provide the structural basis for establishing cell polarity in most eukaryotic cells. Radially round and immotile spermatids from nematodes contain almost no actin or tubulin, but still have the ability to break symmetry to extend a pseudopod and initiate the acquisition of motility powered by the dynamics of cytoskeleton composed of major sperm protein (MSP) during spermiogenesis (sperm activation). However, the signal transduction mechanism of nematode sperm activation and motility acquisition remains poorly understood. Here we show that Ca(2+) oscillations induced by the Ca(2+) release from intracellular Ca(2+) store through inositol (1,4,5)-trisphosphate receptor are required for Ascaris suum sperm activation. The chelation of cytosolic Ca(2+) suppresses the generation of a functional pseudopod, and this suppression can be relieved by introducing exogenous Ca(2+) into sperm cells. Ca(2+) promotes MSP-based sperm motility by increasing mitochondrial membrane potential and thus the energy supply required for MSP cytoskeleton assembly. On the other hand, Ca(2+) promotes MSP disassembly by activating Ca(2+)/calmodulin-dependent serine/threonine protein phosphatase calcineurin. In addition, Ca(2+)/camodulin activity is required for the fusion of sperm-specifi c membranous organelle with the plasma membrane, a regulated exocytosis required for sperm motility. Thus, Ca(2+) plays multifunctional roles during sperm activation in Ascaris suum.
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Affiliation(s)
- Yunlong Shang
- Laboratory of Noncoding RNA, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
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Yarotskyy V, Dirksen RT. Temperature and RyR1 regulate the activation rate of store-operated Ca²+ entry current in myotubes. Biophys J 2012; 103:202-11. [PMID: 22853897 DOI: 10.1016/j.bpj.2012.06.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2011] [Revised: 05/29/2012] [Accepted: 06/04/2012] [Indexed: 01/22/2023] Open
Abstract
Store-operated calcium entry (SOCE) is an important Ca(2+) entry pathway in skeletal muscle. However, direct electrophysiological recording and full characterization of the underlying SOCE current in skeletal muscle cells (I(SkCRAC)) has not been reported. Here, we characterized the biophysical properties, pharmacological profile, and molecular identity of I(SkCRAC) in skeletal myotubes, as well as the regulation of its rate of activation by temperature and the type I ryanodine receptor (RyR1). I(SkCRAC) exhibited many hallmarks of Ca(2+) release activated Ca(2+) currents (I(CRAC)): store dependence, strong inward rectification, positive reversal potential, limited cesium permeability, and sensitivity to SOCE channel blockers. I(SkCRAC) was reduced by siRNA knockdown of stromal interaction molecule 1 and expression of dominant negative Orai1. Average I(SkCRAC) current density at -80mV was 1.00 ± 0.05 pA/pF. In the presence of 20 mM intracellular EGTA, I(SkCRAC) activation occurred over tens of seconds during repetitive depolarization at 0.5Hz and was inhibited by treatment with 100 μM ryanodine. The rate of SOCE activation was reduced threefold in myotubes from RyR1-null mice and increased 4.6-fold at physiological temperatures (35-37°C). These results show that I(SkCRAC) exhibits similar biophysical, pharmacological, and molecular properties as I(CRAC) in nonexcitable cells and its rate of activation during repetitive depolarization is strongly regulated by temperature and RyR1 activity.
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Affiliation(s)
- Viktor Yarotskyy
- Department of Pharmacology and Physiology, University of Rochester Medical Center, Rochester, New York, USA
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Measurement of calcium release due to inositol trisphosphate receptors in skeletal muscle. Methods Mol Biol 2012; 798:383-93. [PMID: 22130849 DOI: 10.1007/978-1-61779-343-1_22] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Calcium transients elicited by IP(3) receptors upon electrical stimulation of skeletal muscle cells (slow calcium signals) are often hard to visualize due to their relatively small amplitude compared to the large transient originated from ryanodine receptors associated to excitation-contraction coupling. The study of slow calcium transients, however, is relevant due to their function in regulation of muscle gene expression and in the process of excitation-transcription coupling. Discussed here are the procedures used to record slow calcium signals from both cultured mouse myotubes and from cultured adult skeletal muscle fibers.
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Quarta M, Scorzeto M, Canato M, Dal Maschio M, Conte D, Blaauw B, Vassanelli S, Reggiani C. The modulation of myogenic cells differentiation using a semiconductor-muscle junction. Biomaterials 2011; 32:4228-37. [DOI: 10.1016/j.biomaterials.2011.02.024] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2010] [Accepted: 02/12/2011] [Indexed: 10/18/2022]
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Sobol KV, Belostotskaya GB, Nesterov VP. Slow calcium waves in cultivated postnatal rat skeletal myocytes. Biophysics (Nagoya-shi) 2010. [DOI: 10.1134/s0006350910060151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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12
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Two inhibitors of store operated Ca2+ entry suppress excitation contraction coupling in frog skeletal muscle. J Muscle Res Cell Motil 2010; 31:127-39. [DOI: 10.1007/s10974-010-9216-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2009] [Accepted: 06/14/2010] [Indexed: 10/19/2022]
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13
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Jorquera G, Juretić N, Jaimovich E, Riveros N. Membrane depolarization induces calcium-dependent upregulation of Hsp70 and Hmox-1 in skeletal muscle cells. Am J Physiol Cell Physiol 2009; 297:C581-90. [PMID: 19570893 DOI: 10.1152/ajpcell.00167.2009] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Heat shock proteins (HSPs) are a conserved family of cytoprotective polypeptides, synthesized by cells in response to stress. Hsp70 and heme oxygenase 1 (Hmox-1) are induced by a variety of cellular stressors in skeletal muscle, playing a role in long-term adaptations and muscle fibers regeneration. Though HSPs expression after exercise has been intensely investigated, the molecular mechanisms concerning Hsp70 and Hmox-1 induction are poorly understood. The aim of this work was to investigate the involvement of calcium in Hsp70 and Hmox-1 expression upon depolarization of skeletal muscle cells. We observed that depolarization of myotubes increased both mRNA levels and protein expression for Hsp70 and Hmox-1. Stimulation in the presence of intracellular calcium chelator BAPTA-AM resulted in a complete inhibition of Hsp70-induced expression. It is known that inositol-1,4,5-trisphophate (IP(3))-mediated slow Ca(2+) transients, evoked by membrane depolarization, are involved in the regulation of gene expression. Here we demonstrated that inhibition of IP(3)-dependent calcium signals decreased both Hsp70 mRNA induction and Hsp70 and Hmox-1 protein expression. Inhibitors of calcium-dependent protein kinase C also abolished Hsp70 mRNA induction. Our results provide evidence that membrane depolarization increases Hsp70 and Hmox-1 expression in cultured skeletal muscle cells, which the effect is critically dependent on Ca(2+) released from IP(3)-sensitive intracellular stores and that it involves PKC as an upstream effector in Hsp70 mRNA-induced expression.
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Affiliation(s)
- Gonzalo Jorquera
- Centro de Estudios Moleculares de la Célula, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago 7, Chile
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Sodium-dependent action potentials induced by brevetoxin-3 trigger both IP3 increase and intracellular Ca2+ release in rat skeletal myotubes. Cell Calcium 2008; 44:289-97. [DOI: 10.1016/j.ceca.2007.12.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2006] [Revised: 12/13/2007] [Accepted: 12/14/2007] [Indexed: 01/27/2023]
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Valdés JA, Gaggero E, Hidalgo J, Leal N, Jaimovich E, Carrasco MA. NFAT activation by membrane potential follows a calcium pathway distinct from other activity-related transcription factors in skeletal muscle cells. Am J Physiol Cell Physiol 2008; 294:C715-25. [DOI: 10.1152/ajpcell.00195.2007] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Depolarization of skeletal muscle cells triggers intracellular Ca2+ signals mediated by ryanodine and inositol 1,4,5-trisphosphate (IP3) receptors. Previously, we have reported that K+-induced depolarization activates transcriptional regulators ERK, cAMP response element-binding protein, c- fos, c- jun, and egr-1 through IP3-dependent Ca2+ release, whereas NF-κB activation is elicited by both ryanodine and IP3 receptor-mediated Ca2+ signals. We have further shown that field stimulation with electrical pulses results in an NF-κB activation increase dependent of the amount of pulses and independent of their frequency. In this work, we report the results obtained for nuclear factor of activated T cells (NFAT)-mediated transcription and translocation generated by both K+ and electrical stimulation protocols in primary skeletal muscle cells and C2C12 cells. The Ca2+ source for NFAT activation is through release by ryanodine receptors and extracellular Ca2+ entry. We found this activation to be independent of the number of pulses within a physiological range of stimulus frequency and enhanced by long-lasting low-frequency stimulation. Therefore, activation of the NFAT signaling pathway differs from that of NF-κB and other transcription factors. Calcineurin enzyme activity correlated well with the relative activation of NFAT translocation and transcription using different stimulation protocols. Furthermore, both K+-induced depolarization and electrical stimulation increased mRNA levels of the type 1 IP3 receptor mediated by calcineurin activity, which suggests that depolarization may regulate IP3 receptor transcription. These results confirm the presence of at least two independent pathways for excitation-transcription coupling in skeletal muscle cells, both dependent on Ca2+ release and triggered by the same voltage sensor but activating different intracellular release channels.
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16
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Juretić N, Urzúa U, Munroe DJ, Jaimovich E, Riveros N. Differential gene expression in skeletal muscle cells after membrane depolarization. J Cell Physiol 2007; 210:819-30. [PMID: 17146758 DOI: 10.1002/jcp.20902] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Skeletal muscle is a highly plastic tissue with a remarkable capacity to adapt itself to challenges imposed by contractile activity. Adaptive response, that include hypertrophy and activation of oxidative mechanisms have been associated with transient changes in transcriptional activity of specific genes. To define the set of genes regulated by a depolarizing stimulus, we used 22 K mouse oligonucleotide microarrays. Total RNA from C2C12 myotubes was obtained at 2, 4, 18, and 24 h after high K+ stimulation. cDNA from control and depolarized samples was labeled with cyanine 3 or 5 dyes prior to microarray hybridization. Loess normalization followed by statistical analysis resulted in 423 differentially expressed genes using an unadjusted P-value < or = 0.01 as cut off. Depolarization affects transcriptional activity of a limited number of genes, mainly associated with metabolism, cell communication and response to stress. A number of genes related to Ca2+ signaling pathways are induced at 4 h, reinforcing the potential role of Ca2+ in early steps of signal transduction that leads to gene expression. Significant changes in the expression of molecules involved in muscle cell structure were observed; K+-depolarization increased Tnni1 and Acta1 mRNA levels in both differentiated C2C12 and rat skeletal muscle cells in primary culture. Of these two, depolarization induced slow Ca2+ transients appear to have a role only in the regulation of Tnni1 transcriptional activity. We suggest that depolarization induced expression of a small set of genes may underlie Ca2+ dependent plasticity of skeletal muscle cells.
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Affiliation(s)
- Nevenka Juretić
- Centro de Estudios Moleculares de la Célula, Facultad de Medicina, Instituto de Ciencias Biomédicas, Universidad de Chile, Santiago, Chile
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17
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Haines N, Stewart BA. Functional roles for beta1,4-N-acetlygalactosaminyltransferase-A in Drosophila larval neurons and muscles. Genetics 2007; 175:671-9. [PMID: 17151241 PMCID: PMC1800592 DOI: 10.1534/genetics.106.065565] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2006] [Accepted: 11/07/2006] [Indexed: 11/18/2022] Open
Abstract
Adult Drosophila mutant for the glycosyltransferase beta1,4-N-acetlygalactosaminyltransferase-A (beta4GalNAcTA) display an abnormal locomotion phenotype, indicating a role for this enzyme, and the glycan structures that it generates, in the neuromuscular system. To investigate the functional role of this enzyme in more detail, we turned to the accessible larval neuromuscular system and report here that larvae mutant for beta4GalNAcTA display distinct nerve and muscle phenotypes. Mutant larvae exhibit abnormal backward crawling, reductions in nerve terminal bouton number, decreased spontaneous transmitter-release frequency, and short, wide muscles. This muscle shape change appears to result from hypercontraction since the individual sarcomeres are shorter in mutant muscles. Analysis of muscle calcium signals showed altered calcium handling in the mutant, suggesting a mechanism by which hypercontraction could occur. All of these phenotypes can be rescued by a transgene carrying the beta4GalNAcTA genomic region. Tissue-specific expression, using the Gal4-UAS system, reveals that neural expression rescues the mutant crawling phenotype, while muscle expression rescues the muscle defect. Tissue-specific expression did not appear to rescue the decrease in neuromuscular junction bouton number, suggesting that this defect arises from cooperation between nerve and muscle. Altogether, these results suggest that beta4GalNAcTA has at least three distinct functional roles.
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Affiliation(s)
- Nicola Haines
- Department of Biology, University of Toronto, Mississauga, Ontario L5L 1C6, Canada.
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18
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Valdés JA, Hidalgo J, Galaz JL, Puentes N, Silva M, Jaimovich E, Carrasco MA. NF-kappaB activation by depolarization of skeletal muscle cells depends on ryanodine and IP3 receptor-mediated calcium signals. Am J Physiol Cell Physiol 2007; 292:C1960-70. [PMID: 17215326 DOI: 10.1152/ajpcell.00320.2006] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Depolarization of skeletal muscle cells by either high external K(+) or repetitive extracellular field potential pulses induces calcium release from internal stores. The two components of this release are mediated by either ryanodine receptors or inositol 1,4,5-trisphosphate (IP(3)) receptors and show differences in kinetics, amplitude, and subcellular localization. We have reported that the transcriptional regulators including ERKs, cAMP/Ca(2+)-response element binding protein, c-fos, c-jun, and egr-1 are activated by K(+)-induced depolarization and that their activation requires IP(3)-dependent calcium release. We presently describe the activation of the nuclear transcription factor NF-kappaB in response to depolarization by either high K(+) (chronic) or electrical pulses (fluctuating). Calcium transients of relative short duration activate an NF-kappaB reporter gene to an intermediate level, whereas long-lasting calcium increases obtained by prolonged electrical stimulation protocols of various frequencies induce maximal activation of NF-kappaB. This activation is independent of extracellular calcium, whereas calcium release mediated by either ryanodine or IP(3) receptors contribute in all conditions tested. NF-kappaB activation is mediated by IkappaBalpha degradation and p65 translocation to the nucleus. Partial blockade by N-acetyl-l-cysteine, a general antioxidant, suggests the participation of reactive oxygen species. Calcium-dependent signaling pathways such as those linked to calcineurin and PKC also contribute to NF-kappaB activation by depolarization, as assessed by blockade through pharmacological agents. These results suggest that NF-kappaB activation in skeletal muscle cells is linked to membrane depolarization and depends on the duration of elevated intracellular calcium. It can be regulated by sequential activation of calcium release mediated by the ryanodine and by IP(3) receptors.
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MESH Headings
- Active Transport, Cell Nucleus
- Animals
- Animals, Newborn
- Calcineurin/metabolism
- Calcium/metabolism
- Calcium Signaling
- Cell Line
- Electric Stimulation
- I-kappa B Proteins/metabolism
- Inositol 1,4,5-Trisphosphate Receptors/metabolism
- Kinetics
- Membrane Potentials
- Mice
- Muscle Fibers, Skeletal/metabolism
- Muscle, Skeletal/cytology
- Muscle, Skeletal/metabolism
- Myoblasts, Skeletal/metabolism
- NF-KappaB Inhibitor alpha
- NF-kappa B/genetics
- NF-kappa B/metabolism
- Potassium/metabolism
- Promoter Regions, Genetic
- Protein Kinase C/metabolism
- Rats
- Rats, Sprague-Dawley
- Reactive Oxygen Species/metabolism
- Ryanodine Receptor Calcium Release Channel/metabolism
- Transcription Factor RelA/metabolism
- Transcription, Genetic
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Affiliation(s)
- Juan Antonio Valdés
- Centro Fondo Nacional de Investigación en Areas Prioritarias de Estudios Moleculares de la Célula, Facultad de Medicina, Universidad de Chile, Santiago, Chile
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19
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Carrasco MA, Hidalgo C. Calcium microdomains and gene expression in neurons and skeletal muscle cells. Cell Calcium 2006; 40:575-83. [PMID: 17034850 DOI: 10.1016/j.ceca.2006.08.021] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2006] [Accepted: 08/23/2006] [Indexed: 01/14/2023]
Abstract
Neurons generate particular calcium microdomains in response to different stimuli. Calcium microdomains have a central role in a variety of neuronal functions. In particular, calcium microdomains participate in long-lasting synaptic plasticity--a neuronal response presumably correlated with cognitive brain functions that requires expression of new gene products. Stimulation of skeletal muscle generates - with few milliseconds delay - calcium microdomains that have a central role in the ensuing muscle contraction. In addition, recent evidence indicates that sustained stimulation of skeletal muscle cells in culture generates calcium microdomains, which stimulate gene expression but not muscle contraction. The mechanisms whereby calcium microdomains activate signaling cascades that lead to the transcription of genes known to participate in specific cellular responses are the central topic of this review. Thus, we will discuss here the signaling pathways and molecular mechanisms, which via activation of particular calcium-dependent transcription factors regulate the expression of specific genes or set of genes in neurons or skeletal muscle cells.
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Affiliation(s)
- M Angélica Carrasco
- Centro FONDAP de Estudios Moleculares de la Célula, Facultad de Medicina, Universidad de Chile, Santiago, Chile.
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20
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Balghi H, Sebille S, Constantin B, Patri S, Thoreau V, Mondin L, Mok E, Kitzis A, Raymond G, Cognard C. Mini-dystrophin expression down-regulates overactivation of G protein-mediated IP3 signaling pathway in dystrophin-deficient muscle cells. ACTA ACUST UNITED AC 2006; 127:171-82. [PMID: 16446505 PMCID: PMC2151485 DOI: 10.1085/jgp.200509456] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We present here evidence for the enhancement of an inositol 1,4,5-trisphosphate (IP3) mediated calcium signaling pathway in myotubes from dystrophin-deficient cell lines (SolC1(−)) as compared to a cell line from the same origin but transfected with mini-dystrophin (SolD(+)). With confocal microscopy, we demonstrated that calcium rise, induced by the perifusion of a solution containing a high potassium concentration, was higher in SolC1(−) than in SolD(+) myotubes. The analysis of amplitude and kinetics of the calcium increase in SolC1(−) and in SolD(+) myotubes during the exposure with SR Ca2+ channel inhibitors (ryanodine and 2-APB) suggested the presence of two mechanisms of SR calcium release: (1) a fast SR calcium release that depended on ryanodine receptors and (2) a slow SR calcium release mediated by IP3 receptors. Detection analyses of mRNAs (reverse transcriptase [RT]-PCR) and proteins (Western blot and immunolocalization) demonstrated the presence of the three known isoforms of IP3 receptors in both SolC1(−) and SolD(+) myotubes. Furthermore, analysis of the kinetics of the rise in calcium revealed that the slow IP3-dependent release may be increased in the SolC1(−) as compared to the SolD(+), suggesting an inhibitory effect of mini-dystrophin in this signaling pathway. Upon incubation with pertussis toxin (PTX), an inhibitory effect similar to that of the IP3R inhibitor (2-APB) was observed on K+-evoked calcium release. This result suggests the involvement of a Gi protein upstream of the IP3 pathway in these stimulation conditions. A hypothetical model is depicted in which both Gi protein and IP3 production could be involved in K+-evoked calcium release as well as a possible interaction with mini-dystrophin. Our findings demonstrate the existence of a potential relationship between mini-dystrophin and SR calcium release as well as a regulatory role of mini-dystrophin on intracellular signaling.
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MESH Headings
- Animals
- Blotting, Western
- Calcium/metabolism
- Calcium Channels/analysis
- Calcium Channels/chemistry
- Calcium Channels/drug effects
- Calcium Channels/genetics
- Calcium Channels/metabolism
- Calcium Channels/physiology
- Calcium Signaling
- Cell Line
- Down-Regulation
- Dystrophin/analysis
- Dystrophin/deficiency
- Dystrophin/genetics
- Dystrophin/physiology
- GTP-Binding Protein alpha Subunits, Gi-Go/physiology
- GTP-Binding Proteins/physiology
- Gene Expression
- Inositol 1,4,5-Trisphosphate/metabolism
- Inositol 1,4,5-Trisphosphate Receptors
- Mice
- Mice, Inbred C3H
- Microscopy, Confocal
- Muscle Fibers, Skeletal/metabolism
- Pertussis Toxin/pharmacology
- Potassium/pharmacology
- RNA, Messenger/analysis
- Receptors, Cytoplasmic and Nuclear/chemistry
- Receptors, Cytoplasmic and Nuclear/genetics
- Receptors, Cytoplasmic and Nuclear/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- Ryanodine Receptor Calcium Release Channel/physiology
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Affiliation(s)
- Haouaria Balghi
- Institut de Physiologie et Biologie Cellulaires, CNRS UMR 6187, Université de Poitiers, France
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21
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Campbell NR, Podugu SP, Ferrari MB. Spatiotemporal characterization of short versus long duration calcium transients in embryonic muscle and their role in myofibrillogenesis. Dev Biol 2006; 292:253-64. [PMID: 16460724 DOI: 10.1016/j.ydbio.2005.11.040] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2005] [Revised: 11/10/2005] [Accepted: 11/29/2005] [Indexed: 10/25/2022]
Abstract
Intracellular calcium (Ca(2+)) signals are essential for several aspects of muscle development, including myofibrillogenesis-the terminal differentiation of the sarcomeric lattice. Ryanodine receptor (RyR) Ca(2+) stores must be operative during this period and contribute to the production of spontaneous global Ca(2+) transients of long duration (LDTs; mean duration approximately 80 s). In this study, high-speed confocal imaging of intracellular Ca(2+) in embryonic myocytes reveals a novel class of spontaneous Ca(2+) transient. These short duration transients (SDTs; mean duration approximately 2 s) are blocked by ryanodine, independent of extracellular Ca(2+), insensitive to changes in membrane potential, and propagate in the subsarcolemmal space. SDTs arise from RyR stores localized to the subsarcolemmal space during myofibrillogenesis. While both LDTs and SDTs occur prior to myofibrillogenesis, LDT production ceases and only SDTs persist during a period of rapid sarcomere assembly. However, eliminating SDTs during this period results in only minor myofibril disruption. On the other hand, artificial extension of LDT production completely inhibits sarcomere assembly. In conjunction with earlier work, these results suggest that LDTs have at least two roles during myofibrillogenesis-activation of sarcoplasmic regulatory cascades and regulation of gene expression. The distinct spatiotemporal patterns of LDTs versus SDTs may be utilized for differential regulation of cytosolic cascades, control of nuclear gene expression, and localized activation of assembly events at the sarcolemma.
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Affiliation(s)
- Nolan R Campbell
- School of Biological Sciences, University of Missouri, 5100 Rockhill Road, Kansas City, MO 64110-2499, USA.
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22
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Cárdenas C, Liberona JL, Molgó J, Colasante C, Mignery GA, Jaimovich E. Nuclear inositol 1,4,5-trisphosphate receptors regulate local Ca2+ transients and modulate cAMP response element binding protein phosphorylation. J Cell Sci 2006; 118:3131-40. [PMID: 16014380 DOI: 10.1242/jcs.02446] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Several lines of evidence indicate that increases in nuclear Ca(2+) have specific biological effects that differ from those of cytosolic Ca(2+), suggesting that they occur independently. The mechanisms involved in controlling nuclear Ca(2+) signaling are both controversial and still poorly understood. Using hypotonic shock combined with mechanical disruption, we obtained and characterized a fraction of purified nuclei from cultured rat skeletal myotubes. Both immunoblot studies and radiolabeled inositol 1,4,5-trisphosphate [IP(3)] binding revealed an important concentration of IP(3) receptors in the nuclear fraction. Immunofluorescence and immunoelectron microscopy studies localized type-1 and type-3 IP(3) receptors in the nucleus with type-1 receptors preferentially localized in the inner nuclear membrane. Type-2 IP(3) receptor was confined to the sarcoplasmic reticulum. Isolated nuclei responded to IP(3) with rapid and transient Ca(2+) concentration elevations, which were inhibited by known blockers of IP(3) signals. Similar results were obtained with isolated nuclei from the 1B5 cell line, which does not express ryanodine receptors but releases nuclear Ca(2+) in an IP(3)-dependent manner. Nuclear Ca(2+) increases triggered by IP(3) evoked phosphorylation of cAMP response element binding protein with kinetics compatible with sequential activation. These results support the idea that Ca(2+) signals, mediated by nuclear IP(3) receptors in muscle cells, are part of a distinct Ca(2+) release component that originates in the nucleus and probably participates in gene regulation mediated by cAMP response element binding protein.
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MESH Headings
- Animals
- Blotting, Western
- Calcium/metabolism
- Calcium Channels/biosynthesis
- Calcium Channels/genetics
- Calcium Channels/metabolism
- Calcium Signaling/physiology
- Cell Nucleus/metabolism
- Cells, Cultured
- Cyclic AMP Response Element-Binding Protein/metabolism
- Fluorometry
- Immunohistochemistry
- Inositol 1,4,5-Trisphosphate/metabolism
- Inositol 1,4,5-Trisphosphate Receptors
- Microscopy, Confocal
- Microscopy, Immunoelectron
- Muscle, Skeletal/cytology
- Muscle, Skeletal/drug effects
- Muscle, Skeletal/metabolism
- Nuclear Envelope/metabolism
- Phosphorylation
- Protein Binding
- Protein Isoforms
- Rats
- Receptors, Cytoplasmic and Nuclear/biosynthesis
- Receptors, Cytoplasmic and Nuclear/genetics
- Receptors, Cytoplasmic and Nuclear/metabolism
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Affiliation(s)
- Cesar Cárdenas
- Centro de Estudios Moleculares de la Célula, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Independencia 1027, Santiago 7, Chile
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23
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Juretić N, García-Huidobro P, Iturrieta JA, Jaimovich E, Riveros N. Depolarization-induced slow Ca2+ transients stimulate transcription of IL-6 gene in skeletal muscle cells. Am J Physiol Cell Physiol 2005; 290:C1428-36. [PMID: 16381797 DOI: 10.1152/ajpcell.00449.2005] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Contracting skeletal muscle produces and releases interleukin-6 (IL-6) in high amounts. Nevertheless, the mechanisms underlying IL-6 expression are not understood. Because inositol-1,4,5-trisphosphate (IP(3))-mediated slow Ca(2+) signals evoked by depolarization of skeletal myotubes appears to play a role in the regulation of gene expression, we examined its involvement on IL-6 transcription. With the use of semiquantitative RT-PCR, we have shown that K(+) depolarization of myotubes induces a transient increase in IL-6 mRNA level, which peaks at 3-4 h and is independent of extracellular Ca(2+). Inhibitors of IP(3)-dependent Ca(2+) signals, like 2-aminoethoxydiphenyl borate (2-APB) and U-73122, decreased activation of IL-6 gene expression as did Ca(2+) signals inhibitor BAPTA-AM, whereas ryanodine, a fast Ca(2+) transient inhibitor, had no effect on IL-6 induction. Depolarization of myotubes transiently transfected with a reporter gene construct, containing 651 bp of IL-6 promoter, induced a twofold increase in promoter activity, which was abolished by either 2-APB or U-73122 and remained unaffected after ryanodine treatment. Site-directed mutagenesis of parental construct allowed us to identify activator protein-1 and NF-kappaB sequences as regulatory elements involved in IL-6 upregulation. Our results provide evidence for involvement of IP(3)-mediated Ca(2+) signals on IL-6 transcription in skeletal muscle cells.
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Affiliation(s)
- Nevenka Juretić
- Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Casilla 70086 Santiago-7, Santiago, Chile
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24
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Koopman WJH, Willems PHGM, Oosterhof A, van Kuppevelt TH, Gielen SCAM. Amplitude modulation of nuclear Ca2+ signals in human skeletal myotubes: A possible role for nuclear Ca2+ buffering. Cell Calcium 2005; 38:141-52. [PMID: 16054687 DOI: 10.1016/j.ceca.2005.06.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2004] [Revised: 05/17/2005] [Accepted: 06/02/2005] [Indexed: 11/20/2022]
Abstract
Video-rate confocal microscopy of Indo-1-loaded human skeletal myotubes was used to assess the relationship between the changes in sarcoplasmic ([Ca(2+)](S)) and nuclear ([Ca(2+)](N)) Ca(2+) concentration during low- and high-frequency electrostimulation. A single stimulus of 10 ms duration transiently increased [Ca(2+)] in both compartments with the same time of onset. Rate and amplitude of the [Ca(2+)] rise were significantly lower in the nucleus (4.0- and 2.5-fold, respectively). Similarly, [Ca(2+)](N) decayed more slowly than [Ca(2+)](S) (mono-exponential time constants of 6.1 and 2.5 s, respectively). After return of [Ca(2+)] to the prestimulatory level, a train of 10 stimuli was applied at a frequency of 1 Hz. The amplitude of the first [Ca(2+)](S) transient was 25% lower than that of the preceding single transient. Thereafter, [Ca(2+)](S) increased stepwise to a maximum that equalled that of the single transient. Similarly, the amplitude of the first [Ca(2+)](N) transient was 20% lower than that of the preceding single transient. In contrast to [Ca(2+)](S), [Ca(2+)](N) then increased to a maximum that was 2.3-fold higher than that of the single transient and equalled that of [Ca(2+)](S). In the nucleus, and to a lesser extent in the sarcoplasm, [Ca(2+)] decreased faster at the end of the stimulus train than after the preceding single stimulus (time constants of 3.3 and 2.1 s, respectively). To gain insight into the molecular principles underlying the shaping of the nuclear Ca(2+) signal, a 3-D mathematical model was constructed. Intriguingly, quantitative modelling required the inclusion of a satiable nuclear Ca(2+) buffer. Alterations in the concentration of this putative buffer had dramatic effects on the kinetics of the nuclear Ca(2+) signal. This finding unveils a possible mechanism by which the skeletal muscle can adapt to changes in physiological demand.
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Affiliation(s)
- Werner J H Koopman
- Department of 160 Biochemistry NCMLS, Radboud University Nijmegen Medical Center, The Netherlands
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25
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Jaimovich E, Mattei C, Liberona JL, Cardenas C, Estrada M, Barbier J, Debitus C, Laurent D, Molgó J. Xestospongin B, a competitive inhibitor of IP3-mediated Ca2+ signalling in cultured rat myotubes, isolated myonuclei, and neuroblastoma (NG108-15) cells. FEBS Lett 2005; 579:2051-7. [PMID: 15811317 DOI: 10.1016/j.febslet.2005.02.053] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2004] [Revised: 02/24/2005] [Accepted: 02/24/2005] [Indexed: 11/25/2022]
Abstract
Xestospongin B, a macrocyclic bis-1-oxaquinolizidine alkaloid extracted from the marine sponge Xestospongia exigua, was highly purified and tested for its ability to block inositol 1,4,5-trisphosphate (IP(3))-induced Ca(2+) release. In a concentration-dependent manner xestospongin B displaced [(3)H]IP(3) from both rat cerebellar membranes and rat skeletal myotube homogenates with an EC(50) of 44.6 +/- 1.1 microM and 27.4 +/- 1.1 microM, respectively. Xestospongin B, depending on the dose, suppressed bradykinin-induced Ca(2+) signals in neuroblastoma (NG108-15) cells, and also selectively blocked the slow intracellular Ca(2+) signal induced by membrane depolarization with high external K(+) (47 mM) in rat skeletal myotubes. This slow Ca(2+) signal is unrelated to muscle contraction, and involves IP(3) receptors. In highly purified isolated nuclei from rat skeletal myotubes, Xestospongin B reduced, or suppressed IP(3)-induced Ca(2+) oscillations with an EC(50) = 18.9 +/- 1.35 microM. In rat myotubes exposed to a Ca(2+)-free medium, Xestospongin B neither depleted sarcoplasmic reticulum Ca(2+) stores, nor modified thapsigargin action and did not affect capacitative Ca(2+) entry after thapsigargin-induced depletion of Ca(2+) stores. Ca(2+)-ATPase activity measured in skeletal myotube homogenates remained unaffected by Xestospongin B. It is concluded that xestospongin B is an effective cell-permeant, competitive inhibitor of IP(3) receptors in cultured rat myotubes, isolated myonuclei, and neuroblastoma (NG108-15) cells.
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Affiliation(s)
- Enrique Jaimovich
- Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, casilla 70005, Santiago 7, Chile
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26
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Gutierrez-Martin Y, Martin-Romero FJ, Henao F. Store-operated calcium entry in differentiated C2C12 skeletal muscle cells. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2005; 1711:33-40. [PMID: 15904661 DOI: 10.1016/j.bbamem.2005.02.017] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2004] [Revised: 02/17/2005] [Accepted: 02/22/2005] [Indexed: 10/25/2022]
Abstract
In this paper, we show further evidences for the existence of store-operated calcium entry in differentiated skeletal muscle C2C12 myotubes after Ca2+ depletion in sarcoplasmic reticulum, using thapsigargin, a potent sarcoplasmic reticulum Ca2+-ATPase inhibitor, caffeine as ryanodine receptor activator, and ATP which activates purinergic receptors. The quenching of fura 2 fluorescence emission by Mn2+ also provided evidences for store-operated calcium entry because this quenching was accelerated when sarcoplasmic reticulum was depleted of Ca2+. Ca2+ entry was sensitive to Ni2+, La3+, Gd3+ and 2-aminoethyl diphenyl borate but resistant to nifedipine, thus excluding L-type Ca2+ channels in this type of calcium entry. Our data obtained using ATP for store depletion suggest that the level of Ca2+ in internal stores could play a role in the regulation of store-operated calcium channel activity in this cell type.
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Affiliation(s)
- Yolanda Gutierrez-Martin
- Departamento de Bioquimica y Biologia Molecular y Genetica, Facultad de Ciencias, Universidad de Extremadura, 06071-Badajoz, Spain
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27
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Cárdenas C, Müller M, Jaimovich E, Pérez F, Buchuk D, Quest AFG, Carrasco MA. Depolarization of skeletal muscle cells induces phosphorylation of cAMP response element binding protein via calcium and protein kinase Calpha. J Biol Chem 2004; 279:39122-31. [PMID: 15262987 DOI: 10.1074/jbc.m401044200] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Membrane depolarization of skeletal muscle cells induces slow inositol trisphosphate-mediated calcium signals that regulate the activity of transcription factors such as the cAMP-response element-binding protein (CREB), jun, and fos. Here we investigated whether such signals regulate CREB phosphorylation via protein kinase C (PKC)-dependent pathways. Western blot analysis revealed the presence of seven isoforms (PKCalpha, -betaI, -betaII, -delta, -epsilon, -, and -zeta) in rat primary myotubes. The PKC inhibitors bisindolymaleimide I and Gö6976, blocked CREB phosphorylation. Chronic exposure to phorbol ester triggered complete down-regulation of several isoforms, but reduced PKCalpha levels to only 40%, and did not prevent CREB phosphorylation upon myotube depolarization. Immunocytochemical analysis revealed selective and rapid PKCalpha translocation to the nucleus following depolarization, which was blocked by 2-amino-ethoxydiphenyl borate, an inositol trisphosphate receptor inhibitor, and by the phospholipase C inhibitor U73122. In C2C12 cells, which expressed PKCalpha,-epsilon, and -zeta, CREB phosphorylation also depended on PKCalpha. These results strongly implicate nuclear PKCalpha translocation in CREB phosphorylation induced by skeletal muscle membrane depolarization.
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MESH Headings
- Active Transport, Cell Nucleus
- Animals
- Animals, Newborn
- Blotting, Western
- Cell Line
- Cell Nucleus/metabolism
- Cells, Cultured
- Cyclic AMP Response Element-Binding Protein/metabolism
- Down-Regulation
- Estrenes/pharmacology
- Immunohistochemistry
- Inositol 1,4,5-Trisphosphate/chemistry
- Mice
- Microscopy, Confocal
- Microscopy, Fluorescence
- Mitogen-Activated Protein Kinase 1/metabolism
- Mitogen-Activated Protein Kinase 3
- Mitogen-Activated Protein Kinases/metabolism
- Muscle, Skeletal/metabolism
- Phorbol Esters/pharmacology
- Phosphorylation
- Potassium/chemistry
- Precipitin Tests
- Protein Isoforms
- Protein Kinase C/metabolism
- Pyrrolidinones/pharmacology
- Rats
- Rats, Sprague-Dawley
- Reverse Transcriptase Polymerase Chain Reaction
- Time Factors
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Affiliation(s)
- César Cárdenas
- Centro de Estudios Moleculares de la Célula, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Independencia 1027, Santiago 7, Chile
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28
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Eltit JM, Hidalgo J, Liberona JL, Jaimovich E. Slow calcium signals after tetanic electrical stimulation in skeletal myotubes. Biophys J 2004; 86:3042-51. [PMID: 15111418 PMCID: PMC1304170 DOI: 10.1016/s0006-3495(04)74353-2] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2003] [Accepted: 01/22/2004] [Indexed: 11/21/2022] Open
Abstract
The fluorescent calcium signal from rat myotubes in culture was monitored after field-stimulation with tetanic protocols. After the calcium signal sensitive to ryanodine and associated to the excitation-contraction coupling, a second long-lasting calcium signal refractory to ryanodine was consistently found. The onset kinetics of this slow signal were slightly modified in nominally calcium-free medium, as were both the frequency and number of pulses during tetanus. No signal was detected in the presence of tetrodotoxin. The participation of the dihydropyridine receptor (DHPR) as the voltage sensor for this signal was assessed by treatment with agonist and antagonist dihydropyridines (Bay K 8644 and nifedipine), showing an enhanced and inhibitory response, respectively. In the dysgenic GLT cell line, which lacks the alpha1(S) subunit of the DHPR, the signal was absent. Transfection of these cells with the alpha1(S) subunit restored the slow signal. In myotubes, the inositol 1,4,5-trisphosphate (IP(3)) mass increase induced by a tetanus protocol preceded in time the slow calcium signal. Both an IP(3) receptor blocker and a phospholipase C inhibitor (xestospongin C and U73122, respectively) dramatically inhibit this signal. Long-lasting, IP(3)-generated slow calcium signals appear to be a physiological response to activity-related fluctuations in membrane potential sensed by the DHPR.
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MESH Headings
- 3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester/pharmacology
- Animals
- Calcium/metabolism
- Calcium Channel Agonists/pharmacology
- Calcium Channel Blockers/pharmacology
- Calcium Channels/metabolism
- Calcium Channels, L-Type/metabolism
- Cell Line
- Cell Membrane/metabolism
- Cells, Cultured
- Electrophysiology/methods
- Enzyme Inhibitors/pharmacology
- Estrenes/pharmacology
- Image Processing, Computer-Assisted
- Inositol 1,4,5-Trisphosphate Receptors
- Kinetics
- Macrocyclic Compounds
- Mice
- Muscle Fibers, Skeletal/metabolism
- Muscle, Skeletal/cytology
- Muscle, Skeletal/metabolism
- Nifedipine/pharmacology
- Oxazoles/pharmacology
- Pyrrolidinones/pharmacology
- Rats
- Receptors, Cytoplasmic and Nuclear/metabolism
- Ryanodine/metabolism
- Ryanodine/pharmacology
- Signal Transduction
- Time Factors
- Transfection
- Type C Phospholipases/metabolism
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Affiliation(s)
- José M Eltit
- Centro de Estudios Moleculares de la Célula, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
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29
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Kunerth S, Langhorst MF, Schwarzmann N, Gu X, Huang L, Yang Z, Zhang L, Mills SJ, Zhang LH, Potter BVL, Guse AH. Amplification and propagation of pacemaker Ca2+ signals by cyclic ADP-ribose and the type 3 ryanodine receptor in T cells. J Cell Sci 2004; 117:2141-9. [PMID: 15054112 DOI: 10.1242/jcs.01063] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Ligation of the T-cell receptor/CD3 complex results in global Ca(2+) signals that are essential for T-cell activation. We have recently reported that these global Ca(2+) signals are preceded by localized pacemaker Ca(2+) signals. Here, we demonstrate for the first time for human T cells that an increase in signal frequency of subcellular pacemaker Ca(2+) signals at sites close to the plasma membrane, in the cytosol and in the nucleus depends on the type 3 ryanodine receptor (RyR) and its modulation by cyclic ADP-ribose. The spatial distribution of D-myo-inositol 1,4,5-trisphosphate receptors and RyRs indicates a concerted action of both of these receptors/Ca(2+) channels in the generation of initial pacemaker signals localized close to the plasma membrane. Inhibition or knockdown of RyRs resulted in significant decreases in (1) the frequency of initial pacemaker signals localized close to the plasma membrane, and (2) the frequency of localized pacemaker Ca(2+) signals in the inner cytosol. Moreover, upon microinjection of cyclic ADP-ribose or upon extracellular addition of its novel membrane-permeant mimic N-1-ethoxymethyl-substituted cyclic inosine diphosphoribose, similarly decreased Ca(2+) signals were observed in both type 3 RyR-knockdown cells and in control cells microinjected with the RyR antagonist Ruthenium Red. Taken together, our results show that, under physiological conditions in human T cells, RyRs play crucial roles in the local amplification and the spatiotemporal development of subcellular Ca(2+) pacemaker signals.
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Affiliation(s)
- Svenja Kunerth
- University Hospital Hamburg-Eppendorf, Center for Experimental Medicine, Institute of Biochemistry and Molecular Biology I: Cellular Signal Transduction, Martinistr. 52, 20246 Hamburg, Germany
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30
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Ibarra C, Estrada M, Carrasco L, Chiong M, Liberona JL, Cardenas C, Díaz-Araya G, Jaimovich E, Lavandero S. Insulin-like growth factor-1 induces an inositol 1,4,5-trisphosphate-dependent increase in nuclear and cytosolic calcium in cultured rat cardiac myocytes. J Biol Chem 2003; 279:7554-65. [PMID: 14660553 DOI: 10.1074/jbc.m311604200] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In the heart, insulin-like growth factor-1 (IGF-1) is a pro-hypertrophic and anti-apoptotic peptide. In cultured rat cardiomyocytes, IGF-1 induced a fast and transient increase in Ca(2+)(i) levels apparent both in the nucleus and cytosol, releasing this ion from intracellular stores through an inositol 1,4,5-trisphosphate (IP(3))-dependent signaling pathway. Intracellular IP(3) levels increased after IGF-1 stimulation in both the presence and absence of extracellular Ca(2+). A different spatial distribution of IP(3) receptor isoforms in cardiomyocytes was found. Ryanodine did not prevent the IGF-1-induced increase of Ca(2+)(i) levels but inhibited the basal and spontaneous Ca(2+)(i) oscillations observed when cardiac myocytes were incubated in Ca(2+)-containing resting media. Spatial analysis of fluorescence images of IGF-1-stimulated cardiomyocytes incubated in Ca(2+)-containing resting media showed an early increase in Ca(2+)(i), initially localized in the nucleus. Calcium imaging suggested that part of the Ca(2+) released by stimulation with IGF-1 was initially contained in the perinuclear region. The IGF-1-induced increase on Ca(2+)(i) levels was prevented by 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid-AM, thapsigargin, xestospongin C, 2-aminoethoxy diphenyl borate, U-73122, pertussis toxin, and betaARKct (a peptide inhibitor of Gbetagamma signaling). Pertussis toxin also prevented the IGF-1-dependent IP(3) mass increase. Genistein treatment largely decreased the IGF-1-induced changes in both Ca(2+)(i) and IP(3). LY29402 (but not PD98059) also prevented the IGF-1-dependent Ca(2+)(i) increase. Both pertussis toxin and U73122 prevented the IGF-1-dependent induction of both ERKs and protein kinase B. We conclude that IGF-1 increases Ca(2+)(i) levels in cultured cardiac myocytes through a Gbetagamma subunit of a pertussis toxin-sensitive G protein-PI3K-phospholipase C signaling pathway that involves participation of IP(3).
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Affiliation(s)
- Cristian Ibarra
- Departament de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago
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31
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Protasi F, Shtifman A, Julian FJ, Allen PD. All three ryanodine receptor isoforms generate rapid cooling responses in muscle cells. Am J Physiol Cell Physiol 2003; 286:C662-70. [PMID: 14592807 DOI: 10.1152/ajpcell.00081.2003] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The rapid cooling (RC) response in muscle is an increase in cytoplasmic Ca2+ concentration ([Ca2+]i) that is probably caused by Ca2+ release from the sarcoplasmic reticulum (SR). However, the molecular bases of this response have not been completely elucidated. Three different isoforms of the SR Ca2+ release channels, or ryanodine receptors (RyRs), have been isolated (RyR1, RyR2, and RyR3). In the current investigation, the RC response was studied in RyR-null muscle cells (1B5) before and after transduction with HSV-1 virions containing the cDNAs encoding for RyR1, RyR2, or RyR3. Cells were loaded with fluo 4-AM to monitor changes in [Ca2+]i and perfused with either cold ( approximately 0 degrees C), room temperature (RT), or RT buffer containing 40 mM caffeine. Control cells showed no significant response to cold or caffeine, whereas robust Ca2+ transients were recorded in response to both RC and caffeine in transduced cells expressing any one of the three RyR isoforms. Our data demonstrate directly that RyRs are responsible for the RC response and that all three isoforms respond in a similar manner. Ca2+ release from RyRs is likely caused by a RC-induced conformational change of the channel from the closed to the open state.
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Affiliation(s)
- Feliciano Protasi
- Department of Anesthesia Research, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachussetts 02115, USA.
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32
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Kubis HP, Hanke N, Scheibe RJ, Meissner JD, Gros G. Ca2+ transients activate calcineurin/NFATc1 and initiate fast-to-slow transformation in a primary skeletal muscle culture. Am J Physiol Cell Physiol 2003; 285:C56-63. [PMID: 12606309 DOI: 10.1152/ajpcell.00377.2002] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The calcineurin-mediated signal transduction via nuclear factor of activated T cells (NFATc1) is involved in upregulating slow myosin heavy chain (MHC) gene expression during fast-to-slow transformation of skeletal muscle cells. This study aims to investigate the Ca2+ signal necessary to activate the calcineurin-NFATc1 cascade in skeletal muscle. Electrostimulation of primary myocytes from rabbit for 24 h induced a distinct fast-to-slow transformation at the MHC mRNA level and a full activation of the calcineurin-NFATc1 pathway, although resting Ca2+ concentration ([Ca2+]i) remained unaltered at 70 nM. During activation, the calcium transients of these myocytes reach a peak concentration of approximately 500 nM. Although 70 nM [Ca2+]i does not activate calcineurin-NFAT, we show by the use of Ca2+ ionophore that the system is fully activated when [Ca2+]i is >or=150 nM in a sustained manner. We conclude that the calcineurin signal transduction pathway and the slow MHC gene in cultured skeletal muscle cells are activated by repetition of the rapid high-amplitude calcium transients that are associated with excitation-contraction coupling rather than by a sustained elevation of resting Ca2+ concentration.
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Affiliation(s)
- Hans-Peter Kubis
- Zentrum Physiologie, Medizinische Hochschule Hannover, D-30625 Hannover, Germany.
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33
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Avila G, Lee EH, Perez CF, Allen PD, Dirksen RT. FKBP12 binding to RyR1 modulates excitation-contraction coupling in mouse skeletal myotubes. J Biol Chem 2003; 278:22600-8. [PMID: 12704193 DOI: 10.1074/jbc.m205866200] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The skeletal muscle sarcoplasmic reticulum (SR) Ca2+ release channel or ryanodine receptor (RyR1) binds four molecules of FKBP12, and the interaction of FKBP12 with RyR1 regulates both unitary and coupled gating of the channel. We have characterized the physiologic effects of previously identified mutations in RyR1 that disrupt FKBP12 binding (V2461G and V2461I) on excitation-contraction (EC) coupling and intracellular Ca2+ homeostasis following their expression in skeletal myotubes derived from RyR1-knockout (dyspedic) mice. Wild-type RyR1-, V246I-, and V2461G-expressing myotubes exhibited similar resting Ca2+ levels and maximal responses to caffeine (10 mm) and cyclopiazonic acid (30 microm). However, maximal voltage-gated Ca2+ release in V2461G-expressing myotubes was reduced by approximately 50% compared with that attributable to wild-type RyR1 (deltaF/Fmax = 1.6 +/- 0.2 and 3.1 +/- 0.4, respectively). Dyspedic myotubes expressing the V2461I mutant protein, that binds FKBP12.6 but not FKBP12, exhibited a comparable reduction in voltage-gated SR Ca2+ release (deltaF/Fmax = 1.0 +/- 0.1). However, voltage-gated Ca2+ release in V2461I-expressing myotubes was restored to a normal level (deltaF/Fmax = 2.9 +/- 0.6) following co-expression of FKBP12.6. None of the mutations that disrupted FKBP binding to RyR1 significantly affected RyR1-mediated enhancement of L-type Ca2+ channel activity (retrograde coupling). These data demonstrate that FKBP12 binding to RyR1 enhances the gain of skeletal muscle EC coupling.
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Affiliation(s)
- Guillermo Avila
- Department of Biochemistry, Cinvestav-IPN, AP 14-740, Mexico City, DF 07000, Mexico
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34
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Carrasco MA, Riveros N, Ríos J, Müller M, Torres F, Pineda J, Lantadilla S, Jaimovich E. Depolarization-induced slow calcium transients activate early genes in skeletal muscle cells. Am J Physiol Cell Physiol 2003; 284:C1438-47. [PMID: 12529240 DOI: 10.1152/ajpcell.00117.2002] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The signaling mechanisms by which skeletal muscle electrical activity leads to changes in gene expression remain largely undefined. We have reported that myotube depolarization induces calcium signals in the cytosol and nucleus via inositol 1,4,5-trisphosphate (IP(3)) and phosphorylation of both ERK1/2 and cAMP-response element-binding protein (CREB). We now describe the calcium dependence of P-CREB and P-ERK induction and of the increases in mRNA of the early genes c-fos, c-jun, and egr-1. Increased phosphorylation and early gene activation were maintained in the absence of extracellular calcium, while the increase in intracellular calcium induced by caffeine could mimic the depolarization stimulus. Depolarization performed either in the presence of the IP(3) inhibitors 2-aminoethoxydiphenyl borate or xestospongin C or on cells loaded with BAPTA-AM, in which slow calcium signals were abolished, resulted in decreased activation of the early genes examined. Both early gene activation and CREB phosphorylation were inhibited by ERK phosphorylation blockade. These data suggest a role for calcium in the transcription-related events that follow membrane depolarization in muscle cells.
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MESH Headings
- Animals
- Caffeine/metabolism
- Calcium/metabolism
- Cells, Cultured
- Cyclic AMP Response Element-Binding Protein/genetics
- Cyclic AMP Response Element-Binding Protein/metabolism
- DNA-Binding Proteins
- Early Growth Response Protein 1
- Enzyme Inhibitors/metabolism
- Gene Expression Regulation, Developmental
- Genes, Immediate-Early
- Genes, fos
- Genes, jun
- Immediate-Early Proteins
- Membrane Potentials/physiology
- Mitogen-Activated Protein Kinases/genetics
- Mitogen-Activated Protein Kinases/metabolism
- Muscle Fibers, Skeletal/cytology
- Muscle Fibers, Skeletal/metabolism
- Muscle, Skeletal/cytology
- Muscle, Skeletal/physiology
- Phosphorylation
- Potassium/metabolism
- RNA, Messenger/metabolism
- Rats
- Rats, Sprague-Dawley
- Signal Transduction/physiology
- Transcription Factors
- Transcriptional Activation
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Affiliation(s)
- Maria Angélica Carrasco
- Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago 6530499, Chile.
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35
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Araya R, Liberona JL, Cárdenas JC, Riveros N, Estrada M, Powell JA, Carrasco MA, Jaimovich E. Dihydropyridine receptors as voltage sensors for a depolarization-evoked, IP3R-mediated, slow calcium signal in skeletal muscle cells. J Gen Physiol 2003; 121:3-16. [PMID: 12508050 PMCID: PMC2217318 DOI: 10.1085/jgp.20028671] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The dihydropyridine receptor (DHPR), normally a voltage-dependent calcium channel, functions in skeletal muscle essentially as a voltage sensor, triggering intracellular calcium release for excitation-contraction coupling. In addition to this fast calcium release, via ryanodine receptor (RYR) channels, depolarization of skeletal myotubes evokes slow calcium waves, unrelated to contraction, that involve the cell nucleus (Jaimovich, E., R. Reyes, J.L. Liberona, and J.A. Powell. 2000. Am. J. Physiol. Cell Physiol. 278:C998-C1010). We tested the hypothesis that DHPR may also be the voltage sensor for these slow calcium signals. In cultures of primary rat myotubes, 10 micro M nifedipine (a DHPR inhibitor) completely blocked the slow calcium (fluo-3-fluorescence) transient after 47 mM K(+) depolarization and only partially reduced the fast Ca(2+) signal. Dysgenic myotubes from the GLT cell line, which do not express the alpha(1) subunit of the DHPR, did not show either type of calcium transient following depolarization. After transfection of the alpha(1) DNA into the GLT cells, K(+) depolarization induced slow calcium transients that were similar to those present in normal C(2)C(12) and normal NLT cell lines. Slow calcium transients in transfected cells were blocked by nifedipine as well as by the G protein inhibitor, pertussis toxin, but not by ryanodine, the RYR inhibitor. Since slow Ca(2+) transients appear to be mediated by IP(3), we measured the increase of IP(3) mass after K(+) depolarization. The IP(3) transient seen in control cells was inhibited by nifedipine and was absent in nontransfected dysgenic cells, but alpha(1)-transfected cells recovered the depolarization-induced IP(3) transient. In normal myotubes, 10 micro M nifedipine, but not ryanodine, inhibited c-jun and c-fos mRNA increase after K(+) depolarization. These results suggest a role for DHPR-mediated calcium signals in regulation of early gene expression. A model of excitation-transcription coupling is presented in which both G proteins and IP(3) appear as important downstream mediators after sensing of depolarization by DHPR.
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Affiliation(s)
- Roberto Araya
- Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago 6530499, Chile
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36
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Hidalgo J, Liberona JL, Molgó J, Jaimovich E. Pacific ciguatoxin-1b effect over Na+ and K+ currents, inositol 1,4,5-triphosphate content and intracellular Ca2+ signals in cultured rat myotubes. Br J Pharmacol 2002; 137:1055-62. [PMID: 12429578 PMCID: PMC1573594 DOI: 10.1038/sj.bjp.0704980] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
1. The action of the main ciguatoxin involved in ciguatera fish poisoning in the Pacific region (P-CTX-1b) was studied in myotubes originated from rat skeletal muscle cells kept in primary culture. 2. The effect of P-CTX-1b on sodium currents at short times of exposure (up to 1 min) showed a moderate increase in peak Na+ current. During prolonged exposures, P-CTX-1b decreased the peak Na+ current. This action was always accompanied by an increase of leakage currents, tail currents and outward Na+ currents, resulting in an intracellular Na+ accumulation. This effect is blocked by prior exposure to tetrodotoxin (TTX) and becomes evident only after washout of TTX. 3. Low to moderate concentrations of P-CTX-1b (2-5 nM) partially blocked potassium currents in a manner that was dependent on the membrane potential. 4. P-CTX-1b (2-12 nM) caused a small membrane depolarization (3-5 mV) and an increase in the frequency of spontaneous action potential discharges that reached in general low frequencies (0.1-0.5 Hz). 5. P-CTX-1b (10 nM) caused a transient increase of intracellular inositol 1,4,5-trisphosphate (IP(3)) mass levels, which was blocked by TTX. 6. In the presence of P-CTX-1b (10 nM) and in the absence of external Ca2+, the intracellular Ca2+ levels show a transient increase in the cytoplasm as well as in the nuclei. The time course of this effect may reflect the action of IP(3) over internal stores activated by P-CTX-1b-induced membrane depolarization.
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Affiliation(s)
- Jorge Hidalgo
- Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Casilla 70005, Correo 7, Santiago, Chile.
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37
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Bootman MD, Collins TJ, Mackenzie L, Roderick HL, Berridge MJ, Peppiatt CM. 2-aminoethoxydiphenyl borate (2-APB) is a reliable blocker of store-operated Ca2+ entry but an inconsistent inhibitor of InsP3-induced Ca2+ release. FASEB J 2002; 16:1145-50. [PMID: 12153982 DOI: 10.1096/fj.02-0037rev] [Citation(s) in RCA: 578] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Since its introduction to Ca2+ signaling in 1997, 2-aminoethoxydiphenyl borate (2-APB) has been used in many studies to probe for the involvement of inositol 1,4,5-trisphosphate receptors in the generation of Ca2+ signals. Due to reports of some nonspecific actions of 2-APB, and the fact that its principal antagonistic effect is on Ca2+ entry rather than Ca2+ release, this compound may not have the utility first suggested. However, 2-APB has thrown up some interesting results, particularly with respect to store-operated Ca2+ entry in nonexcitable cells. These data indicate that although it must be used with caution, 2-APB can be useful in probing certain aspects of Ca2+ signaling.
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Affiliation(s)
- Martin D Bootman
- Laboratory of Molecular Signalling, The Babraham Institute, Babraham, Cambridge CB2 4AT, UK.
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38
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Solovyova N, Fernyhough P, Glazner G, Verkhratsky A. Xestospongin C empties the ER calcium store but does not inhibit InsP3-induced Ca2+ release in cultured dorsal root ganglia neurones. Cell Calcium 2002; 32:49-52. [PMID: 12127062 DOI: 10.1016/s0143-4160(02)00094-5] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The action of Xestospongin C (XeC) on calcium concentration in the cytosol ([Ca2+]i) and within the lumen of endoplasmic reticulum (ER) ([Ca2+]L) was studied using cultured dorsal root ganglia (DRG) neurones. Application of 2.5 microM of XeC triggered a slow [Ca2+]i transient as measured by Fura-2 video-imaging. The kinetics and amplitude of XeC-induced [Ca2+]i response was similar to that triggered by 1 microM thapsigargin (TG). The [Ca2+]L was monitored in cells loaded with low-affinity Ca2+ indicator Mag-Fura-2. The cytosolic portion of Mag-Fura-2 was removed by permeabilisation of the plasmalemma with saponin. Application of XeC to these permeabilised neurones resulted in a slow depletion of the ER Ca2+ store. XeC, however, failed to inhibit inositol 1,4,5-trisphosphate (InsP3)-induced [Ca2+]L responses. We conclude that XeC is a potent inhibitor of sarco(endo)plasmic reticulum calcium ATPase, and it cannot be regarded as a specific inhibitor of InsP3 receptors in cultured DRG neurones.
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Affiliation(s)
- N Solovyova
- School of Biological Sciences, The University of Manchester, 1.124 Stopford Building, Oxford Road, Manchester, UK
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39
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Formigli L, Francini F, Meacci E, Vassalli M, Nosi D, Quercioli F, Tiribilli B, Bencini C, Piperio C, Bruni P, Orlandini SZ. Sphingosine 1-phosphate induces Ca2+ transients and cytoskeletal rearrangement in C2C12 myoblastic cells. Am J Physiol Cell Physiol 2002; 282:C1361-73. [PMID: 11997251 DOI: 10.1152/ajpcell.00378.2001] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In many cell systems, sphingosine 1-phosphate (SPP) increases cytosolic Ca2+ concentration ([Ca2+]i) by acting as intracellular mediator and extracellular ligand. We recently demonstrated (Meacci E, Cencetti F, Formigli L, Squecco R, Donati C, Tiribilli B, Quercioli F, Zecchi-Orlandini S, Francini F, and Bruni P. Biochem J 362: 349-357, 2002) involvement of endothelial differentiation gene (Edg) receptors (Rs) specific for SPP in agonist-mediated Ca2+ response of a mouse skeletal myoblastic (C2C12) cell line. Here, we investigated the Ca2+ sources of SPP-mediated Ca2+ transients in C2C12 cells and the possible correlation of ion response to cytoskeletal rearrangement. Confocal fluorescence imaging of C2C12 cells preloaded with Ca2+ dye fluo 3 revealed that SPP elicited a transient Ca2+ increase propagating as a wave throughout the cell. This response required extracellular and intracellular Ca2+ pool mobilization. Indeed, it was significantly reduced by removal of external Ca2+, pretreatment with nifedipine (blocker of L-type plasma membrane Ca2+ channels), and inositol 1,4,5-trisphosphate [Ins(1,4,5)P3]-mediated Ca2+ pathway inhibitors. Involvement of EdgRs was tested with suramin (specific inhibitor of Edg-3). Fluorescence associated with Ins(1,4,5)P3Rs and L-type Ca2+ channels was evident in C2C12 cells. SPP also induced C2C12 cell contraction. This event, however, was unrelated to [Ca2+]i increase, because the two phenomena were temporally shifted. We propose that SPP may promote C2C12 cell contraction through Ca2+-independent mechanisms.
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MESH Headings
- Aniline Compounds
- Animals
- Caffeine/pharmacology
- Calcium/metabolism
- Calcium Channel Blockers/pharmacology
- Calcium Channels, L-Type/metabolism
- Calcium Signaling/drug effects
- Calcium Signaling/physiology
- Cell Line
- Cytoskeleton/drug effects
- Cytoskeleton/metabolism
- Cytoskeleton/ultrastructure
- DNA-Binding Proteins/antagonists & inhibitors
- Diglycerides/biosynthesis
- Extracellular Space/metabolism
- Fluorescent Dyes
- I-kappa B Proteins
- Inositol 1,4,5-Trisphosphate/biosynthesis
- Inositol 1,4,5-Trisphosphate/pharmacology
- Intracellular Fluid/metabolism
- Lysophospholipids
- Mice
- Microscopy, Confocal
- Muscle Contraction/drug effects
- Muscle, Skeletal/cytology
- Muscle, Skeletal/drug effects
- Muscle, Skeletal/metabolism
- NF-KappaB Inhibitor alpha
- Potassium/pharmacology
- Receptors, Lysophospholipid
- Ryanodine Receptor Calcium Release Channel/drug effects
- Signal Transduction/drug effects
- Signal Transduction/physiology
- Sphingosine/analogs & derivatives
- Sphingosine/pharmacology
- Suramin/pharmacology
- Xanthenes
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Affiliation(s)
- Lucia Formigli
- Department of Anatomy, Histology, and Forensic Medicine, University of Florence, 50134 Florence, Italy
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Meacci E, Cencetti F, Formigli L, Squecco R, Donati C, Tiribilli B, Quercioli F, Zecchi Orlandini S, Francini F, Bruni P. Sphingosine 1-phosphate evokes calcium signals in C2C12 myoblasts via Edg3 and Edg5 receptors. Biochem J 2002; 362:349-57. [PMID: 11853542 PMCID: PMC1222394 DOI: 10.1042/0264-6021:3620349] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Sphingosine 1-phosphate (SPP) is a bioactive lipid that exerts multiple biological effects in a large variety of cell types, acting as either an intracellular messenger or an extracellular ligand coupled to Edg-family receptors (where Edg stands for endothelial differentiation gene). Here we report that in C(2)C(12) myoblasts SPP elicited significant Ca(2+) mobilization. Analysis of the process using a confocal laser-scanning microscope showed that the Ca(2+) response occurred in a high percentage of cells, despite variations in amplitude and kinetics. Quantitative analysis of SPP-induced Ca(2+) transients performed with a spectrophotofluorimeter showed that the rise in Ca(2+) was strictly dependent on availability of extracellular Ca(2+). Cell treatment with pertussis toxin partially prevented the Ca(2+) response induced by SPP, indicating that G(i)-coupled-receptors were involved. Indeed, SPP action was shown to be mediated by agonist-specific Edg receptors. In particular, suramin, an antagonist of the SPP-specific receptor Edg3, as well as down-regulation of Edg3 by cell transfection with antisense oligodeoxyribonucleotides (ODN), significantly reduced agonist-mediated Ca(2+) mobilization. Moreover, an antisense ODN designed to inhibit Edg5 expression also decreased the SPP-induced rise in Ca(2+), although to a lesser extent than that observed by inhibiting Edg3. On the contrary, the SPP response was unaffected in myoblasts loaded with antisense ODN specific for Edg1. Remarkably, the concomitant inhibition of Edg3 and Edg5 receptors abolished the SPP-induced Ca(2+) increase, supporting the notion that Ca(2+) mobilization in C(2)C(12) cells induced by SPP is a receptor-mediated process that involves Edg3 and Edg5, but not Edg1.
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Affiliation(s)
- Elisabetta Meacci
- Dipartimento di Scienze Biochimiche, Università degli Studi di Firenze, Viale G.B. Morgagni 50, 50134 Florence, Italy
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Powell JA, Carrasco MA, Adams DS, Drouet B, Rios J, Müller M, Estrada M, Jaimovich E. IP3 receptor function and localization in myotubes: an unexplored Ca2+ signaling pathway in skeletal muscle. J Cell Sci 2001; 114:3673-83. [PMID: 11707519 DOI: 10.1242/jcs.114.20.3673] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We present evidence for an unexplored inositol 1,4,5-trisphosphate-mediated Ca2+ signaling pathway in skeletal muscle. RT-PCR methods confirm expression of all three known isotypes of the inositol trisphosphate receptor in cultured rodent muscle. Confocal microscopy of cultured mouse muscle, doubly labeled for inositol receptor type 1 and proteins of known distribution, reveals that the receptors are localized to the I band of the sarcoplasmic reticulum, and this staining is continuous with staining of the nuclear envelope region. These results suggest that the receptors are positioned to mediate a slowly propagating Ca2+ wave that follows the fast Ca2+ transient upon K+ depolarization. This slow wave, imaged using fluo-3, resulted in an increase in nucleoplasmic Ca2+ lasting tens of seconds, but not contraction; the slow wave was blocked by both the inositol trisphosphate receptor inhibitor 2-aminoethoxydiphenyl borate and the phospholipase C inhibitor U-73122. To test the hypothesis that these slow Ca2+ signals are involved in signal cascades leading to regulation of gene expression, we assayed for early effects of K+ depolarization on mitogen-activated protein kinases, specifically extracellular-signal related kinases 1 and 2 and the transcription factor cAMP response element-binding protein (CREB). Within 30-60 seconds following depolarization, phosphorylation of both the kinases and CREB was evident and could be inhibited by 2-aminoethoxydiphenyl borate. These results suggest a signaling system mediated by Ca2+ and inositol trisphosphate that could regulate gene expression in muscle cells.
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Affiliation(s)
- J A Powell
- Department of Biological Sciences, Smith College, Northampton, MA 01063, USA.
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