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Wang H, Xie M, Rizzi G, Li X, Tan K, Fussenegger M. Identification of Sclareol As a Natural Neuroprotective Ca v 1.3-Antagonist Using Synthetic Parkinson-Mimetic Gene Circuits and Computer-Aided Drug Discovery. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2022; 9:e2102855. [PMID: 35040584 PMCID: PMC8895113 DOI: 10.1002/advs.202102855] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2021] [Revised: 11/30/2021] [Indexed: 05/14/2023]
Abstract
Parkinson's disease (PD) results from selective loss of substantia nigra dopaminergic (SNc DA) neurons, and is primarily caused by excessive activity-related Ca2+ oscillations. Although L-type voltage-gated calcium channel blockers (CCBs) selectively inhibiting Cav 1.3 are considered promising candidates for PD treatment, drug discovery is hampered by the lack of high-throughput screening technologies permitting isoform-specific assessment of Cav-antagonistic activities. Here, a synthetic-biology-inspired drug-discovery platform enables identification of PD-relevant drug candidates. By deflecting Cav-dependent activation of nuclear factor of activated T-cells (NFAT)-signaling to repression of reporter gene translation, they engineered a cell-based assay where reporter gene expression is activated by putative CCBs. By using this platform in combination with in silico virtual screening and a trained deep-learning neural network, sclareol is identified from a essential oils library as a structurally distinctive compound that can be used for PD pharmacotherapy. In vitro studies, biochemical assays and whole-cell patch-clamp recordings confirmed that sclareol inhibits Cav 1.3 more strongly than Cav 1.2 and decreases firing responses of SNc DA neurons. In a mouse model of PD, sclareol treatment reduced DA neuronal loss and protected striatal network dynamics as well as motor performance. Thus, sclareol appears to be a promising drug candidate for neuroprotection in PD patients.
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Affiliation(s)
- Hui Wang
- Department of Biosystems Science and EngineeringETH ZurichMattenstrasse 26Basel4058Switzerland
- Present address:
Lonza AGLonzastrasseVisp3930Switzerland
| | - Mingqi Xie
- Department of Biosystems Science and EngineeringETH ZurichMattenstrasse 26Basel4058Switzerland
- Present address:
Key Laboratory of Growth Regulation and Translational Research of Zhejiang ProvinceSchool of Life SciencesWestlake UniversityShilongshan Road 18HangzhouP. R. China
| | - Giorgio Rizzi
- BiozentrumUniversity of BaselKlingelbergstrasse 50/70Basel4056Switzerland
- Present address:
Inscopix IncEmbarcadero WayPalo AltoCA94303USA
| | - Xin Li
- Department of Biosystems Science and EngineeringETH ZurichMattenstrasse 26Basel4058Switzerland
- Present address:
Key Laboratory of Growth Regulation and Translational Research of Zhejiang ProvinceSchool of Life SciencesWestlake UniversityShilongshan Road 18HangzhouP. R. China
| | - Kelly Tan
- BiozentrumUniversity of BaselKlingelbergstrasse 50/70Basel4056Switzerland
| | - Martin Fussenegger
- Department of Biosystems Science and EngineeringETH ZurichMattenstrasse 26Basel4058Switzerland
- University of BaselFaculty of ScienceMattenstrasse 26BaselCH‐4058Switzerland
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2
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Little HJ. L-Type Calcium Channel Blockers: A Potential Novel Therapeutic Approach to Drug Dependence. Pharmacol Rev 2021; 73:127-154. [PMID: 34663686 DOI: 10.1124/pharmrev.120.000245] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
This review describes interactions between compounds, primarily dihydropyridines, that block L-type calcium channels and drugs that cause dependence, and the potential importance of these interactions. The main dependence-inducing drugs covered are alcohol, psychostimulants, opioids, and nicotine. In preclinical studies, L-type calcium channel blockers prevent or reduce important components of dependence on these drugs, particularly their reinforcing actions and the withdrawal syndromes. The channel blockers also reduce the development of tolerance and/or sensitization, and they have no intrinsic dependence liability. In some instances, their effects include reversal of brain changes established during drug dependence. Prolonged treatment with alcohol, opioids, psychostimulant drugs, or nicotine causes upregulation of dihydropyridine binding sites. Few clinical studies have been carried out so far, and reports are conflicting, although there is some evidence of effectiveness of L-channel blockers in opioid withdrawal. However, the doses of L-type channel blockers used clinically so far have necessarily been limited by potential cardiovascular problems and may not have provided sufficient central levels of the drugs to affect neuronal dihydropyridine binding sites. New L-type calcium channel blocking compounds are being developed with more selective actions on subtypes of L-channel. The preclinical evidence suggests that L-type calcium channels may play a crucial role in the development of dependence to different types of drugs. Mechanisms for this are proposed, including changes in the activity of mesolimbic dopamine neurons, genomic effects, and alterations in synaptic plasticity. Newly developed, more selective L-type calcium channel blockers could be of considerable value in the treatment of drug dependence. SIGNIFICANCE STATEMENT: Dependence on drugs is a very serious health problem with little effective treatment. Preclinical evidence shows drugs that block particular calcium channels, the L-type, reduce dependence-related effects of alcohol, opioids, psychostimulants, and nicotine. Clinical studies have been restricted by potential cardiovascular side effects, but new, more selective L-channel blockers are becoming available. L-channel blockers have no intrinsic dependence liability, and laboratory evidence suggests they reverse previously developed effects of dependence-inducing drugs. They could provide a novel approach to addiction treatment.
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Affiliation(s)
- Hilary J Little
- Section of Alcohol Research, National Addiction Centre, Institute of Psychiatry, King's College, London, United Kingdom
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Labandeira-Garcia JL, Valenzuela R, Costa-Besada MA, Villar-Cheda B, Rodriguez-Perez AI. The intracellular renin-angiotensin system: Friend or foe. Some light from the dopaminergic neurons. Prog Neurobiol 2020; 199:101919. [PMID: 33039415 PMCID: PMC7543790 DOI: 10.1016/j.pneurobio.2020.101919] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 08/20/2020] [Accepted: 10/04/2020] [Indexed: 12/11/2022]
Abstract
The renin-angiotensin system (RAS) is one of the oldest hormone systems in vertebrate phylogeny. RAS was initially related to regulation of blood pressure and sodium and water homeostasis. However, local or paracrine RAS were later identified in many tissues, including brain, and play a major role in their physiology and pathophysiology. In addition, a major component, ACE2, is the entry receptor for SARS-CoV-2. Overactivation of tissue RAS leads several oxidative stress and inflammatory processes involved in aging-related degenerative changes. In addition, a third level of RAS, the intracellular or intracrine RAS (iRAS), with still unclear functions, has been observed. The possible interaction between the intracellular and extracellular RAS, and particularly the possible deleterious or beneficial effects of the iRAS activation are controversial. The dopaminergic system is particularly interesting to investigate the RAS as important functional interactions between dopamine and RAS have been observed in the brain and several peripheral tissues. Our recent observations in mitochondria and nucleus of dopaminergic neurons may clarify the role of the iRAS. This may be important for the developing of new therapeutic strategies, since the effects on both extracellular and intracellular RAS must be taken into account, and perhaps better understanding of COVID-19 cell mechanisms.
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Affiliation(s)
- Jose L Labandeira-Garcia
- Laboratory of Cellular and Molecular Neurobiology of Parkinson's Disease, Research Center for Molecular Medicine and Chronic Diseases (CIMUS), Health Research Institute (IDIS), University of Santiago de Compostela, Santiago de Compostela, Spain; Networking Research Center on Neurodegenerative Diseases (CiberNed), Madrid, Spain.
| | - Rita Valenzuela
- Laboratory of Cellular and Molecular Neurobiology of Parkinson's Disease, Research Center for Molecular Medicine and Chronic Diseases (CIMUS), Health Research Institute (IDIS), University of Santiago de Compostela, Santiago de Compostela, Spain; Networking Research Center on Neurodegenerative Diseases (CiberNed), Madrid, Spain
| | - Maria A Costa-Besada
- Laboratory of Cellular and Molecular Neurobiology of Parkinson's Disease, Research Center for Molecular Medicine and Chronic Diseases (CIMUS), Health Research Institute (IDIS), University of Santiago de Compostela, Santiago de Compostela, Spain; Networking Research Center on Neurodegenerative Diseases (CiberNed), Madrid, Spain
| | - Begoña Villar-Cheda
- Laboratory of Cellular and Molecular Neurobiology of Parkinson's Disease, Research Center for Molecular Medicine and Chronic Diseases (CIMUS), Health Research Institute (IDIS), University of Santiago de Compostela, Santiago de Compostela, Spain; Networking Research Center on Neurodegenerative Diseases (CiberNed), Madrid, Spain
| | - Ana I Rodriguez-Perez
- Laboratory of Cellular and Molecular Neurobiology of Parkinson's Disease, Research Center for Molecular Medicine and Chronic Diseases (CIMUS), Health Research Institute (IDIS), University of Santiago de Compostela, Santiago de Compostela, Spain; Networking Research Center on Neurodegenerative Diseases (CiberNed), Madrid, Spain
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Fernandez DC, Fogerson PM, Lazzerini Ospri L, Thomsen MB, Layne RM, Severin D, Zhan J, Singer JH, Kirkwood A, Zhao H, Berson DM, Hattar S. Light Affects Mood and Learning through Distinct Retina-Brain Pathways. Cell 2018; 175:71-84.e18. [PMID: 30173913 PMCID: PMC6190605 DOI: 10.1016/j.cell.2018.08.004] [Citation(s) in RCA: 253] [Impact Index Per Article: 42.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Revised: 05/03/2018] [Accepted: 08/02/2018] [Indexed: 01/25/2023]
Abstract
Light exerts a range of powerful biological effects beyond image vision, including mood and learning regulation. While the source of photic information affecting mood and cognitive functions is well established, viz. intrinsically photosensitive retinal ganglion cells (ipRGCs), the central mediators are unknown. Here, we reveal that the direct effects of light on learning and mood utilize distinct ipRGC output streams. ipRGCs that project to the suprachiasmatic nucleus (SCN) mediate the effects of light on learning, independently of the SCN's pacemaker function. Mood regulation by light, on the other hand, requires an SCN-independent pathway linking ipRGCs to a previously unrecognized thalamic region, termed perihabenular nucleus (PHb). The PHb is integrated in a distinctive circuitry with mood-regulating centers and is both necessary and sufficient for driving the effects of light on affective behavior. Together, these results provide new insights into the neural basis required for light to influence mood and learning.
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Affiliation(s)
| | | | | | - Michael B Thomsen
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Robert M Layne
- Department of Biology, University of Maryland, College Park, MD 20742, USA
| | - Daniel Severin
- Department of Neuroscience, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Jesse Zhan
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Joshua H Singer
- Department of Biology, University of Maryland, College Park, MD 20742, USA
| | - Alfredo Kirkwood
- Department of Neuroscience, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Haiqing Zhao
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218, USA
| | - David M Berson
- Department of Neuroscience, Brown University, Providence, RI 02912, USA
| | - Samer Hattar
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218, USA.
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5
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The intracellular angiotensin system buffers deleterious effects of the extracellular paracrine system. Cell Death Dis 2017; 8:e3044. [PMID: 28880266 PMCID: PMC5636983 DOI: 10.1038/cddis.2017.439] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Revised: 07/25/2017] [Accepted: 07/31/2017] [Indexed: 12/30/2022]
Abstract
The 'classical' renin-angiotensin system (RAS) is a circulating system that controls blood pressure. Local/paracrine RAS, identified in a variety of tissues, including the brain, is involved in different functions and diseases, and RAS blockers are commonly used in clinical practice. A third type of RAS (intracellular/intracrine RAS) has been observed in some types of cells, including neurons. However, its role is still unknown. The present results indicate that in brain cells the intracellular RAS counteracts the intracellular superoxide/H2O2 and oxidative stress induced by the extracellular/paracrine angiotensin II acting on plasma membrane receptors. Activation of nuclear receptors by intracellular or internalized angiotensin triggers a number of mechanisms that protect the cell, such as an increase in the levels of protective angiotensin type 2 receptors, intracellular angiotensin, PGC-1α and IGF-1/SIRT1. Interestingly, this protective mechanism is altered in isolated nuclei from brains of aged animals. The present results indicate that at least in the brain, AT1 receptor blockers acting only on the extracellular or paracrine RAS may offer better protection of cells.
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6
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Ross CL, Siriwardane M, Almeida-Porada G, Porada CD, Brink P, Christ GJ, Harrison BS. The effect of low-frequency electromagnetic field on human bone marrow stem/progenitor cell differentiation. Stem Cell Res 2015; 15:96-108. [PMID: 26042793 PMCID: PMC4516580 DOI: 10.1016/j.scr.2015.04.009] [Citation(s) in RCA: 101] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Revised: 04/17/2015] [Accepted: 04/27/2015] [Indexed: 12/12/2022] Open
Abstract
Human bone marrow stromal cells (hBMSCs, also known as bone marrow-derived mesenchymal stem cells) are a population of progenitor cells that contain a subset of skeletal stem cells (hSSCs), able to recreate cartilage, bone, stroma that supports hematopoiesis and marrow adipocytes. As such, they have become an important resource in developing strategies for regenerative medicine and tissue engineering due to their self-renewal and differentiation capabilities. The differentiation of SSCs/BMSCs is dependent on exposure to biophysical and biochemical stimuli that favor early and rapid activation of the in vivo tissue repair process. Exposure to exogenous stimuli such as an electromagnetic field (EMF) can promote differentiation of SSCs/BMSCs via ion dynamics and small signaling molecules. The plasma membrane is often considered to be the main target for EMF signals and most results point to an effect on the rate of ion or ligand binding due to a receptor site acting as a modulator of signaling cascades. Ion fluxes are closely involved in differentiation control as stem cells move and grow in specific directions to form tissues and organs. EMF affects numerous biological functions such as gene expression, cell fate, and cell differentiation, but will only induce these effects within a certain range of low frequencies as well as low amplitudes. EMF has been reported to be effective in the enhancement of osteogenesis and chondrogenesis of hSSCs/BMSCs with no documented negative effects. Studies show specific EMF frequencies enhance hSSC/BMSC adherence, proliferation, differentiation, and viability, all of which play a key role in the use of hSSCs/BMSCs for tissue engineering. While many EMF studies report significant enhancement of the differentiation process, results differ depending on the experimental and environmental conditions. Here we review how specific EMF parameters (frequency, intensity, and time of exposure) significantly regulate hSSC/BMSC differentiation in vitro. We discuss optimal conditions and parameters for effective hSSC/BMSC differentiation using EMF treatment in an in vivo setting, and how these can be translated to clinical trials.
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Affiliation(s)
- Christina L Ross
- Wake Forest Institute for Regenerative Medicine, USA; Wake Forest Center for Integrative Medicine, Wake Forest School of Medicine, Medical Center Blvd., Winston-Salem, NC 27157, USA.
| | | | | | | | - Peter Brink
- Department of Physiology and Biophysics, SUNY Stony Brook, Stony Brook, NY 11794, USA
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7
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Park YH, Mueller BH, McGrady NR, Ma HY, Yorio T. AMPA receptor desensitization is the determinant of AMPA receptor mediated excitotoxicity in purified retinal ganglion cells. Exp Eye Res 2015; 132:136-50. [PMID: 25643624 DOI: 10.1016/j.exer.2015.01.026] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Revised: 12/08/2014] [Accepted: 01/29/2015] [Indexed: 01/15/2023]
Abstract
The ionotropic glutamate receptors (iGLuR) have been hypothesized to play a role in neuronal pathogenesis by mediating excitotoxic death. Previous studies on iGluR in the retina have focused on two broad classes of receptors: NMDA and non-NMDA receptors including the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic receptor (AMPAR) and kainate receptor. In this study, we examined the role of receptor desensitization on the specific excitotoxic effects of AMPAR activation on primary retinal ganglion cells (RGCs). Purified rat RGCs were isolated from postnatal day 4-7 Sprague-Dawley rats. Calcium imaging was used to identify the functionality of the AMPARs and selectivity of the s-AMPA agonist. Phosphorylated CREB and ERK1/2 expression were performed following s-AMPA treatment. s-AMPA excitotoxicity was determined by JC-1 mitochondrial membrane depolarization assay, caspase 3/7 luciferase activity assay, immunoblot analysis for α-fodrin, and Live (calcein AM)/Dead (ethidium homodimer-1) assay. RGC cultures of 98% purity, lacking Iba1 and GFAP expression were used for the present studies. Isolated prenatal RGCs expressed calcium permeable AMPAR and s-AMPA (100 μM) treatment of cultured RGCs significantly increased phosphorylation of CREB but not that of ERK1/2. A prolonged (6 h) AMPAR activation in purified RGCs using s-AMPA (100 μM) did not depolarize the RGC mitochondrial membrane potential. In addition, treatment of cultured RGCs with s-AMPA, both in the presence and absence of trophic factors (BDNF and CNTF), did not increase caspase 3/7 activities or the cleavage of α-fodrin (neuronal apoptosis marker), as compared to untreated controls. Lastly, a significant increase in cell survival of RGCs was observed after s-AMPA treatment as compared to control untreated RGCs. However, preventing the desensitization of AMPAR with the treatment with either kainic acid (100 μM) or the combination of s-AMPA and cyclothiazide (50 μM) significantly reduced cell survivability. Activation of the AMPAR in RGCs does not appear to activate a signaling cascade to apoptosis, suggesting that RGCs in vitro are not susceptible to AMPA excitotoxicity as previously hypothesized. Conversely, preventing AMPAR desensitization through differential agonist activation caused AMPAR mediated excitotoxicity. Activation of the AMPAR in increasing CREB phosphorylation was dependent on the presence of calcium, which may help explain this action in increasing RGC survival.
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Affiliation(s)
- Yong H Park
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX, USA; North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, TX, USA.
| | - Brett H Mueller
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX, USA; North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, TX, USA
| | - Nolan R McGrady
- Department of Cell Biology and Immunology, University of North Texas Health Science Center, Fort Worth, TX, USA; North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, TX, USA
| | - Hai-Ying Ma
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX, USA; North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, TX, USA
| | - Thomas Yorio
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX, USA; North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, TX, USA.
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8
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Baker KD, Edwards TM, Rickard NS. The role of intracellular calcium stores in synaptic plasticity and memory consolidation. Neurosci Biobehav Rev 2013; 37:1211-39. [PMID: 23639769 DOI: 10.1016/j.neubiorev.2013.04.011] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Revised: 04/18/2013] [Accepted: 04/22/2013] [Indexed: 12/20/2022]
Abstract
Memory processing requires tightly controlled signalling cascades, many of which are dependent upon intracellular calcium (Ca(2+)). Despite this, most work investigating calcium signalling in memory formation has focused on plasma membrane channels and extracellular sources of Ca(2+). The intracellular Ca(2+) release channels, ryanodine receptors (RyRs) and inositol (1,4,5)-trisphosphate receptors (IP3Rs) have a significant capacity to regulate intracellular Ca(2+) signalling. Evidence at both cellular and behavioural levels implicates both RyRs and IP3Rs in synaptic plasticity and memory formation. Pharmacobehavioural experiments using young chicks trained on a single-trial discrimination avoidance task have been particularly useful by demonstrating that RyRs and IP3Rs have distinct roles in memory formation. RyR-dependent Ca(2+) release appears to aid the consolidation of labile memory into a persistent long-term memory trace. In contrast, IP3Rs are required during long-term memory. This review discusses various functions for RyRs and IP3Rs in memory processing, including neuro- and glio-transmitter release, dendritic spine remodelling, facilitating vasodilation, and the regulation of gene transcription and dendritic excitability. Altered Ca(2+) release from intracellular stores also has significant implications for neurodegenerative conditions.
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Affiliation(s)
- Kathryn D Baker
- School of Psychology and Psychiatry, Monash University, Clayton 3800, Victoria, Australia.
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9
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Ryan MM, Mason-Parker SE, Tate WP, Abraham WC, Williams JM. Rapidly induced gene networks following induction of long-term potentiation at perforant path synapses in vivo. Hippocampus 2012; 21:541-53. [PMID: 20108223 DOI: 10.1002/hipo.20770] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The canonical view of the maintenance of long-term potentiation (LTP), a widely accepted experimental model for memory processes, is that new gene transcription contributes to its consolidation; however, the gene networks involved are unknown. To address this issue, we have used high-density Rat 230.2 Affymetrix arrays to establish a set of genes induced 20-min post-LTP, and using Ingenuity Pathway network analysis tools we have investigated how these early responding genes are interrelated. This analysis identified LTP-induced regulatory networks in which the transcription factors (TFs) nuclear factor-KB and serum response factor, which, to date, have not been widely recognized as coordinating the early gene response, play a key role alongside the more well-known TFs cyclic AMP response element-binding protein, and early growth response 1. Analysis of gene-regulatory promoter sites and chromosomal locations of the genes within the dataset reinforced the importance of these molecules in the early gene response and predicted that the coordinated action might arise from gene clustering on particular chromosomes. We have also identified a transcription-based response that affects mitogen-activated protein kinase signaling pathways and protein synthesis during the stabilization of the LTP response. Furthermore, evidence from biological function, networks, and regulatory analyses showed convergence on genes related to development, proliferation, and neurogenesis, suggesting that these functions are regulated early following LTP induction. This raises the interesting possibility that LTP-related gene expression plays a role in both synaptic reorganization and neurogenesis.
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Affiliation(s)
- Margaret M Ryan
- Department of Anatomy and Structural Biology, Otago School of Medical Sciences, P.O. Box 913, Dunedin, New Zealand
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Hagenston AM, Bading H. Calcium signaling in synapse-to-nucleus communication. Cold Spring Harb Perspect Biol 2011; 3:a004564. [PMID: 21791697 DOI: 10.1101/cshperspect.a004564] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Changes in the intracellular concentration of calcium ions in neurons are involved in neurite growth, development, and remodeling, regulation of neuronal excitability, increases and decreases in the strength of synaptic connections, and the activation of survival and programmed cell death pathways. An important aspect of the signals that trigger these processes is that they are frequently initiated in the form of glutamatergic neurotransmission within dendritic trees, while their completion involves specific changes in the patterns of genes expressed within neuronal nuclei. Accordingly, two prominent aims of research concerned with calcium signaling in neurons are determination of the mechanisms governing information conveyance between synapse and nucleus, and discovery of the rules dictating translation of specific patterns of inputs into appropriate and specific transcriptional responses. In this article, we present an overview of the avenues by which glutamatergic excitation of dendrites may be communicated to the neuronal nucleus and the primary calcium-dependent signaling pathways by which synaptic activity can invoke changes in neuronal gene expression programs.
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Affiliation(s)
- Anna M Hagenston
- CellNetworks-Cluster of Excellence, Department of Neurobiology, Interdisciplinary Center for Neurosciences, University of Heidelberg, 69120 Heidelberg, Germany
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11
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Gross J, Angerstein M, Fuchs J, Stute K, Mazurek B. Expression analysis of prestin and selected transcription factors in newborn rats. Cell Mol Neurobiol 2011; 31:1089-101. [PMID: 21614551 DOI: 10.1007/s10571-011-9708-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2011] [Accepted: 05/11/2011] [Indexed: 01/16/2023]
Abstract
Transcription factors (TFs) have a central role to play in regulating gene expression. To analyze the co-expression patterns of selected TFs with the motor protein prestin of the outer hair cells, we applied an real-time PCR approach combining several kinds of information: (i) expression changes during postnatal development, (ii) expression changes by exposure of organotypic cultures of the organ of Corti to factors which significantly affect prestin expression [thyroid hormone (T4), retinoic acid (RA), butyric acid (BA), increased KCl concentration] and (iii) changes along the apical-basal gradient. We found that the mRNA levels of the TF Brn-3c (Pou4f3), a member of the POU family, are significantly associated with the regulation of prestin during postnatal development and in cultures supplemented with T4 (0.5 μM), BA (0.5-2.0 mM), and high KCl (50 mM) concentration. The mRNA level of the constitutively active TF C/ebpb (CCAAT/enhancer binding protein beta) correlates positively with the prestin expression during postnatal development and in cultures exposed to T4 and RA (50-100 μM). The mRNA levels of the calcium-dependent TF CaRF correlates significantly with the prestin expression in cultures exposed to T4 and high KCl concentration. The observed coexpression patterns may suggest that the TFs Brn-3c, C/ebpb, and Carf contribute to regulating the expression of prestin under the investigated conditions.
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Affiliation(s)
- Johann Gross
- Molecular Biology Research Laboratory, Department of Otorhinolaryngology, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany.
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12
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Mouse mutants for the nicotinic acetylcholine receptor ß2 subunit display changes in cell adhesion and neurodegeneration response genes. PLoS One 2011; 6:e18626. [PMID: 21547082 PMCID: PMC3081876 DOI: 10.1371/journal.pone.0018626] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2010] [Accepted: 03/08/2011] [Indexed: 11/19/2022] Open
Abstract
Mice lacking expression of the ß2 subunit of the neuronal nicotinic acetylcholine receptor (CHRNB2) display abnormal retinal waves and a dispersed projection of retinal ganglion cell (RGC) axons to their dorsal lateral geniculate nuclei (dLGNs). Transcriptomes of LGN tissue from two independently generated Chrnb2−/− mutants and from wildtype mice were obtained at postnatal day 4 (P4), during the normal period of segregation of eye-specific afferents to the LGN. Microarray analysis reveals reduced expression of genes located on the cell membrane or in extracellular space, and of genes active in cell adhesion and calcium signaling. In particular, mRNA for cadherin 1 (Cdh1), a known axon growth regulator, is reduced to nearly undetectable levels in the LGN of P4 mutant mice and Lypd2 mRNA is similarly suppressed. Similar analysis of retinal tissue shows increased expression of crumbs 1 (Crb1) and chemokine (C-C motif) ligand 21 (Ccl21) mRNAs in Chrnb2−/− mutant animals. Mutations in these genes are associated with retinal neuronal degeneration. The retinas of Chrnb2−/− mutants are normal in appearance, but the increased expression of these genes may also be involved in the abnormal projection patterns of RGC to the LGN. These data may provide the tools to distinguish the interplay between neural activity and molecular expression. Finally, comparison of the transcriptomes of the two different Chrnb2−/− mutant strains reveals the effects of genetic background upon gene expression.
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Importance of Cationic Channels for Functioning of the Nuclear Envelope of Neurons as a Calcium Store. NEUROPHYSIOLOGY+ 2011. [DOI: 10.1007/s11062-011-9154-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Fedorenko EA, Duzhii DE, Marchenko SM. Voltage Dependence of the Activity of Inositol Trisphosphate Receptors of the Nuclear Envelope of Hippocampal Pyramidal Neurons. NEUROPHYSIOLOGY+ 2010. [DOI: 10.1007/s11062-010-9106-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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15
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Discriminative behavioral assessment unveils remarkable reactive astrocytosis and early molecular correlates in basal ganglia of 3-nitropropionic acid subchronic treated rats. Neurochem Int 2010; 56:152-60. [DOI: 10.1016/j.neuint.2009.09.013] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2009] [Revised: 08/21/2009] [Accepted: 09/18/2009] [Indexed: 01/28/2023]
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16
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Akiba Y, Sasaki H, Huerta PT, Estevez AG, Baker H, Cave JW. gamma-Aminobutyric acid-mediated regulation of the activity-dependent olfactory bulb dopaminergic phenotype. J Neurosci Res 2009; 87:2211-21. [PMID: 19301430 DOI: 10.1002/jnr.22055] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
gamma-Aminobutyric acid (GABA) regulates the proliferation and migration of olfactory bulb (OB) interneuron progenitors derived from the subventricular zone (SVZ), but the role of GABA in the differentiation of these progenitors has been largely unexplored. This study examines the role of GABA in the differentiation of OB dopaminergic interneurons using neonatal forebrain organotypic slice cultures prepared from transgenic mice expressing green fluorescent protein (GFP) under the control of the tyrosine hydroxylase (Th) gene promoter (ThGFP). KCl-mediated depolarization of the slices induced ThGFP expression. The addition of GABA to the depolarized slices further increased GFP fluorescence by inducing ThGFP expression in an additional set of periglomerular cells. These findings show that GABA promoted differentiation of SVZ-derived OB dopaminergic interneurons and suggest that GABA indirectly regulated Th expression and OB dopaminergic neuron differentiation through an acceleration of the maturation rate for the dopaminergic progenitors. Additional studies revealed that the effect of GABA on ThGFP expression required activation of L- and P/Q-type Ca2+ channels as well as GABA(A) and GABA(B) receptors. These voltage-gated Ca2+ channels and GABA receptors have previously been shown to be required for the coexpressed GABAergic phenotype in the OB interneurons. Together, these findings suggest that Th expression and the differentiation of OB dopaminergic interneurons are coupled to the coexpressed GABAergic phenotype and demonstrate a novel role for GABA in neurogenesis.
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Affiliation(s)
- Yosuke Akiba
- Burke Medical Research Institute, White Plains, NY 10605. USA
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17
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18
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Bezin S, Charpentier G, Lee HC, Baux G, Fossier P, Cancela JM. Regulation of nuclear Ca2+ signaling by translocation of the Ca2+ messenger synthesizing enzyme ADP-ribosyl cyclase during neuronal depolarization. J Biol Chem 2008; 283:27859-27870. [PMID: 18632662 DOI: 10.1074/jbc.m804701200] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In neurons, voltage-gated Ca(2+) channels and nuclear Ca(2+) signaling play important roles, such as in the regulation of gene expression. However, the link between electrical activity and biochemical cascade activation involved in the generation of the nuclear Ca(2+) signaling is poorly understood. Here we show that depolarization of Aplysia neurons induces the translocation of ADP-ribosyl cyclase, a Ca(2+) messenger synthesizing enzyme, from the cytosol into the nucleus. The translocation is dependent on Ca(2+) influx mainly through the voltage-dependent L-type Ca(2+) channels. We report also that specific nucleoplasmic Ca(2+) signals can be induced by three different calcium messengers, cyclic ADP-ribose, nicotinic acid adenine dinucleotide phosphate (NAADP), both produced by the ADP-ribosyl cyclase, and inositol 1,4,5-trisphosphate (IP(3)). Moreover, our pharmacological data show that NAADP acts on its own receptor, which cooperates with the IP(3) and the ryanodine receptors to generate nucleoplasmic Ca(2+) oscillations. We propose a new model where voltage-dependent L-type Ca(2+) channel-induced nuclear translocation of the cytosolic cyclase is a crucial step in the fine tuning of nuclear Ca(2+) signals in neurons.
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Affiliation(s)
- Stéphanie Bezin
- Laboratoire de Neurobiologie Cellulaire et Moléculaire, CNRS, UPR 9040, 1, Avenue de la Terrasse, 91198 Gif-Sur-Yvette Cedex, France
| | - Gilles Charpentier
- Laboratoire de Neurobiologie Cellulaire et Moléculaire, CNRS, UPR 9040, 1, Avenue de la Terrasse, 91198 Gif-Sur-Yvette Cedex, France; Université Bordeaux 1 Laboratoire DMPFCS, IECB, 2, Rue Robert Escarpit, 33607 Pessac, France
| | - Hon Cheung Lee
- Department of Physiology, University of Hong Kong, 4/F Lab Block, Faculty of Medicine Building, 21 Sassoon Road, Hong Kong
| | - Gérard Baux
- Laboratoire de Neurobiologie Cellulaire et Moléculaire, CNRS, UPR 9040, 1, Avenue de la Terrasse, 91198 Gif-Sur-Yvette Cedex, France
| | - Philippe Fossier
- Laboratoire de Neurobiologie Cellulaire et Moléculaire, CNRS, UPR 9040, 1, Avenue de la Terrasse, 91198 Gif-Sur-Yvette Cedex, France
| | - José-Manuel Cancela
- Laboratoire de Neurobiologie Cellulaire et Moléculaire, CNRS, UPR 9040, 1, Avenue de la Terrasse, 91198 Gif-Sur-Yvette Cedex, France.
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19
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Kerchove CM, Luna MSA, Zablith MB, Lazari MFM, Smaili SS, Yamanouye N. Alpha1-adrenoceptors trigger the snake venom production cycle in secretory cells by activating phosphatidylinositol 4,5-bisphosphate hydrolysis and ERK signaling pathway. Comp Biochem Physiol A Mol Integr Physiol 2008; 150:431-7. [PMID: 18555716 DOI: 10.1016/j.cbpa.2008.04.607] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2008] [Revised: 04/30/2008] [Accepted: 04/30/2008] [Indexed: 11/26/2022]
Abstract
Loss of venom from the venom gland after biting or manual extraction leads to morphological changes in venom secreting cells and the start of a cycle of production of new venom. We have previously shown that stimulation of both alpha- and beta-adrenoceptors in the secretory cells of the venom gland is essential for the onset of the venom production cycle in Bothrops jararaca. We investigated the signaling pathway by which the alpha-adrenoceptor initiates the venom production cycle. Our results show that the alpha(1)-adrenoceptor subtype is present in venom gland of the snake. In quiescent cells, stimulation of alpha(1)-adrenoceptor with phenylephrine increased the total inositol phosphate concentration, and this effect was blocked by the phospholipase C inhibitor U73122. Phenylephrine mobilized Ca(2+) from thapsigargin-sensitive stores and increased protein kinase C activity. In addition, alpha(1)-adrenoceptor stimulation increased the activity of ERK 1/2, partially via protein kinase C. Using RT-PCR approach we obtained a partial sequence of a snake alpha(1)-adrenoceptor (260 bp) with higher identity with alpha(1D) and alpha(1B)-adrenoceptors from different species. These results suggest that alpha(1)-adrenoceptors in the venom secreting cells are probably coupled to a G(q) protein and trigger the venom production cycle by activating the phosphatidylinositol 4,5-bisphosphate and ERK signaling pathway.
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Affiliation(s)
- Celine M Kerchove
- Laboratório de Farmacologia, Instituto Butantan, Av. Vital Brazil, 1500, 05503-900, São Paulo, SP, Brazil
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20
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Simonetti M, Giniatullin R, Fabbretti E. Mechanisms mediating the enhanced gene transcription of P2X3 receptor by calcitonin gene-related peptide in trigeminal sensory neurons. J Biol Chem 2008; 283:18743-52. [PMID: 18460469 DOI: 10.1074/jbc.m800296200] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The molecular mechanisms underlying migraine pain remain unclear and probably require sustained facilitation in pain-sensing P2X(3) receptors gated by extracellular ATP in nociceptive sensory neurons. The major migraine mediator calcitonin gene-related peptide (CGRP) is known to sensitize P2X(3) receptors to increase impulse flow to brainstem trigeminal nuclei. This process is mediated via changes in the expression and function of P2X(3) receptors initially through enhanced trafficking and, later, perhaps through augmented synthesis of P2X(3) receptors. To clarify the mechanisms responsible for CGRP-evoked long lasting alterations in P2X(3) receptors, we used as a model mouse trigeminal ganglion neurons in culture. CGRP activated Ca(2+)-calmodulin-dependent kinase II, which became localized to the perimembrane region and neuronal processes, a phenomenon already apparent after 30 min and accompanied by a parallel increase in cAMP-response element-binding protein (CREB) phosphorylation and nuclear translocation. These effects triggered increased P2X(3) receptor transcription and were prevented by expressing a dominant negative form of CREB. Increased P2X(3) receptor synthesis was partly mediated by endogenous brain-derived neurotrophic factor (BDNF) because of its block by anti-BDNF antibodies and mimicry by exogenous BDNF. Immunocytochemistry experiments indicated distinct subpopulations of BDNF- or CGRP-sensitive trigeminal neurons with only partial overlap. The present data indicate a novel mechanism for enhancing P2X(3) receptor expression and function in trigeminal sensory neurons by CGRP via CREB phosphorylation. BDNF was an intermediate to extend the sensitizing effect of CGRP also to CGRP-insensitive neurons. This combinatorial action could serve as a powerful process to amplify and prolong pain mediated by P2X(3) receptors.
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Affiliation(s)
- Manuela Simonetti
- Neurobiology Sector and Italian Institute of Technology Unit, International School for Advanced Studies (SISSA), 34014 Trieste, Italy
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21
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Mazurek B, Haupt H, Amarjargal N, Yarin YM, Machulik A, Gross J. Up-regulation of prestin mRNA expression in the organs of Corti of guinea pigs and rats following unilateral impulse noise exposure. Hear Res 2007; 231:73-83. [PMID: 17592749 DOI: 10.1016/j.heares.2007.05.008] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2006] [Revised: 05/15/2007] [Accepted: 05/15/2007] [Indexed: 12/27/2022]
Abstract
Prestin is the motor protein of the outer hair cells (OHCs) and is required for both their electromotility and for cochlear amplification. We investigated the prestin mRNA expression in guinea pigs and rats in relation to the degree of noise-induced hearing loss (NIHL) induced by unilateral impulse noise exposure (167dB peak SPL) for 2.5-5 min. Distortion product otoacoustic emissions (DPOAE) and auditory brainstem responses were recorded before and one week post exposure. Prestin mRNA was examined by quantitative reverse transcription-polymerase chain reaction. Either the whole organs of Corti or the apical, middle and basal parts were examined separately. The specimens were pooled and grouped according to the degree of NIHL measured in the exposed ears. In rats, the number of hair cells was counted. A clear base-to-apex gradient in the prestin mRNA expression was found to exist in guinea pig and rat controls. In both species, there was an increase in the number of prestin RNA transcripts at a mean NIHL of about 15-25 dB indicating an up-regulation in the remaining intact cells. In rats, this degree of NIHL corresponded to an OHC loss of about 40%. Interestingly, the contralateral ears also revealed an up-regulation of prestin mRNA accompanied by significant DPOAE improvements.
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Affiliation(s)
- Birgit Mazurek
- Charité-Universitätsmedizin Berlin, Campus Charité Mitte, Department of Otorhinolaryngology, Molecular Biological Research Laboratory, Charitéplatz 1, 10117 Berlin, Germany.
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22
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Gong P, Han J, Reddig K, Li HS. A potential dimerization region of dCAMTA is critical for termination of fly visual response. J Biol Chem 2007; 282:21253-8. [PMID: 17537720 DOI: 10.1074/jbc.m701223200] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
CAMTAs are a group of Ca(2+)/calmodulin binding transcription activators that are implicated in brain tumor suppression, cardiac hypertrophy, and plant sensory responses. The sole fly CAMTA, dCAMTA, stimulates expression of an F-box gene, dFbxl4, to potentiate rhodopsin deactivation, which enables rapid termination of fly visual responses. Here we report that a dCAMTA fragment associated with a full-length protein in co-transfected human embryonic kidney 293 cells. The interaction site was mapped to a region within the DNA-binding CG-1 domain. With this potential dimerization site mutated, the full-length dCAMTA had defective nuclear localization. In transgenic flies, this mutant dCAMTA variant failed to stimulate expression of dFbxl4 and rescue the slow termination of light response phenotype of a dCAMTA null mutant fly. Our data suggest that dCAMTA may function as a dimer during fly visual regulation and that the CG-1 domain may mediate dimerization of CAMTA transcription factors.
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Affiliation(s)
- Ping Gong
- Department of Neurobiology, University of Massachusetts Medical School, Worcester, Massachusetts 01605, USA
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23
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Raymond CR. LTP forms 1, 2 and 3: different mechanisms for the ‘long’ in long-term potentiation. Trends Neurosci 2007; 30:167-75. [PMID: 17292975 DOI: 10.1016/j.tins.2007.01.007] [Citation(s) in RCA: 142] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2006] [Revised: 12/21/2006] [Accepted: 01/31/2007] [Indexed: 11/23/2022]
Abstract
Long-term potentiation (LTP) of synaptic transmission is a primary experimental model of memory formation in neuronal circuits. Because of the intellectual appeal and scientific fecundity of the field, it is perhaps unsurprising that the literature on LTP contains many complex and often contradictory findings. Recognition that LTP is not a unitary phenomenon and mechanisms can differ between brain regions has resolved some controversy. However, further categorization can be made of mechanistically discrete forms of LTP at the same set of synapses. LTP1, LTP2 and LTP3 have previously been defined according to differences in the longevity and general molecular mechanisms of LTP. This review aims to reinvigorate and extend this concept as a useful framework to disentangle the mechanisms of LTP.
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Affiliation(s)
- Clarke R Raymond
- Division of Neuroscience, The John Curtin School of Medical Research, The Australian National University Canberra, ACT 0200, Australia.
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24
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Sun S, Liu Y, Lipsky S, Cho M. Physical manipulation of calcium oscillations facilitates osteodifferentiation of human mesenchymal stem cells. FASEB J 2007; 21:1472-80. [PMID: 17264165 DOI: 10.1096/fj.06-7153com] [Citation(s) in RCA: 145] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The role of cytosolic calcium oscillation has long been recognized in the regulation of cellular and molecular interactions. Information embedded in calcium oscillation can provide molecular cues for cell behavior such as cell differentiation. Although calcium dynamics are versatile and likely to depend on the cell type, the calcium dynamics in human mesenchymal stem cells (hMSCs) and its role in differentiation are yet to be fully elucidated. In the present study we characterized the calcium oscillation profiles in hMSCs before and after subjecting the cells to the osteoinductive factors. Our findings indicate that the calcium spikes decreased rapidly with osteodifferentiation to a level observed in terminally differentiated human osteoblasts. In addition, the calcium oscillations appear to serve as a bidirectional signal during hMSC differentiation. While an altered calcium oscillation pattern may be an indicator for hMSC differentiation, it is also likely to be involved in directing hMSC differentiation. Treatment of hMSCs with a noninvasive electrical stimulation, for example, not only altered the calcium oscillations but also facilitated osteodifferentiation. Regulation of calcium oscillation by external physical stimulation could amplify hMSC differentiation into a tissue-specific lineage and may offer an alternate biotechnology to harness the unique properties of stem cells.
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Affiliation(s)
- Shan Sun
- Department of Bioengineering, University of Illinois, Chicago, Chicago, IL 60607, USA
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25
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Spontaneously active ion channels of membranes of the nuclear envelope of hippocampal pyramidal neurons. NEUROPHYSIOLOGY+ 2007. [DOI: 10.1007/s11062-007-0001-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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26
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Abstract
UNLABELLED Injury to the nerve can produce changes in dorsal horn function and pain. This facilitated processing may be mediated in part by voltage-sensitive calcium channels. Activation of these channels increases intracellular calcium, thereby mediating transmitter release and activating cascades serving to alter membrane excitability and initiate protein transcription. Molecular techniques reveal the complexity and multiplicity of these channels. At the spinal level, blocking of several of these calcium channels, notably those of the N type, can prominently alter pain behavior. These effects are consistent with the high levels of expression on primary afferents and dorsal horn neurons of these channels. More recently, agents binding to auxiliary subunits such as the alpha2delta of these calcium channels diminish excitability of the membrane without completely blocking channel function. Drugs that bind to this site, highly expressed in the superficial dorsal horn, will diminish neuropathic pain states. Continuing developments in our understanding of these channel functions promises to advance the control of aberrant spinal functions initiated by nerve injury. PERSPECTIVE Pharmacologic studies showing the role of spinal voltage-sensitive calcium channels in neuropathic pain models provide evidence suggesting their applicability in human pain states.
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Affiliation(s)
- Tony L Yaksh
- Department of Anesthesiology, University of California, San Diego, La Jolla, California 92093-0818, USA.
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27
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Verkhratsky A. Physiology and Pathophysiology of the Calcium Store in the Endoplasmic Reticulum of Neurons. Physiol Rev 2005; 85:201-79. [PMID: 15618481 DOI: 10.1152/physrev.00004.2004] [Citation(s) in RCA: 557] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The endoplasmic reticulum (ER) is the largest single intracellular organelle, which is present in all types of nerve cells. The ER is an interconnected, internally continuous system of tubules and cisterns, which extends from the nuclear envelope to axons and presynaptic terminals, as well as to dendrites and dendritic spines. Ca2+release channels and Ca2+pumps residing in the ER membrane provide for its excitability. Regulated ER Ca2+release controls many neuronal functions, from plasmalemmal excitability to synaptic plasticity. Enzymatic cascades dependent on the Ca2+concentration in the ER lumen integrate rapid Ca2+signaling with long-lasting adaptive responses through modifications in protein synthesis and processing. Disruptions of ER Ca2+homeostasis are critically involved in various forms of neuropathology.
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Affiliation(s)
- Alexei Verkhratsky
- The University of Manchester, Faculty of Biological Sciences, United Kingdom.
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Quesada I, Martin F, Roche E, Soria B. Nutrients induce different Ca(2+) signals in cytosol and nucleus in pancreatic beta-cells. Diabetes 2004; 53 Suppl 1:S92-5. [PMID: 14749272 DOI: 10.2337/diabetes.53.2007.s92] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Specific activation of Ca(2+)-dependent functions is achieved by the particular dynamics and local restriction of Ca(2+) signals. It has been shown that changes in amplitude, duration, or frequency of Ca(2+) signals modulate gene transcription. Thus, Ca(2+) variations should be finely controlled within the nucleus. Although a variety of mechanisms in the nuclear membrane have been demonstrated to regulate nuclear Ca(2+), the existence of an autonomous Ca(2+) homeostasis within the nucleus is still questioned. In the pancreatic beta-cell, besides their effect on insulin secretion, Ca(2+) messages generated by nutrients also exert their action on gene expression. However, the dynamics of these Ca(2+) signals in relation to nuclear function have been explored little in islet cells. In the current study, Ca(2+) changes both in the nucleoplasm and in the cytosol of INS-1 and pancreatic beta-cells were monitored using spot confocal microscopy. We show that nutrients trigger Ca(2+) signals of higher amplitude in the nucleus than in the cytosol. These amplitude-modulated Ca(2+) signals transmitted to the nucleus might play an important role in the control of gene expression in the pancreatic beta-cell.
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Affiliation(s)
- Ivan Quesada
- Department of Bioengineering, University of Washington, Seattle, Washington, USA
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Soria B, Quesada I, Ropero AB, Pertusa JA, Martín F, Nadal A. Novel players in pancreatic islet signaling: from membrane receptors to nuclear channels. Diabetes 2004; 53 Suppl 1:S86-91. [PMID: 14749271 DOI: 10.2337/diabetes.53.2007.s86] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Glucose and other nutrients regulate many aspects of pancreatic islet physiology. This includes not only insulin release, but also insulin synthesis and storage and other aspects of beta-cell biology, including cell proliferation, apoptosis, differentiation, and gene expression. This implies that in addition to the well-described signals for insulin release, other intracellular signaling mechanisms are needed. Here we describe the role of global and local Ca(2+) signals in insulin release, the regulation of these signals by new membrane receptors, and the generation of nuclear Ca(2+) signals involved in gene expression. An integrated view of these pathways should improve the present description of the beta-cell biology and provide new targets for novel drugs.
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Affiliation(s)
- Bernat Soria
- Institute of Bioengineering, Miguel Hernandez University, Alicante, Spain.
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