51
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Li F, Eriksen J, Finer-Moore J, Chang R, Nguyen P, Bowen A, Myasnikov A, Yu Z, Bulkley D, Cheng Y, Edwards RH, Stroud RM. Ion transport and regulation in a synaptic vesicle glutamate transporter. Science 2020; 368:893-897. [PMID: 32439795 DOI: 10.1126/science.aba9202] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Accepted: 03/27/2020] [Indexed: 12/28/2022]
Abstract
Synaptic vesicles accumulate neurotransmitters, enabling the quantal release by exocytosis that underlies synaptic transmission. Specific neurotransmitter transporters are responsible for this activity and therefore are essential for brain function. The vesicular glutamate transporters (VGLUTs) concentrate the principal excitatory neurotransmitter glutamate into synaptic vesicles, driven by membrane potential. However, the mechanism by which they do so remains poorly understood owing to a lack of structural information. We report the cryo-electron microscopy structure of rat VGLUT2 at 3.8-angstrom resolution and propose structure-based mechanisms for substrate recognition and allosteric activation by low pH and chloride. A potential permeation pathway for chloride intersects with the glutamate binding site. These results demonstrate how the activity of VGLUTs can be coordinated with large shifts in proton and chloride concentrations during the synaptic vesicle cycle to ensure normal synaptic transmission.
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Affiliation(s)
- Fei Li
- Department of Biochemistry and Biophysics, University of California San Francisco (UCSF) School of Medicine, San Francisco, CA, USA.,Departments of Neurology and Physiology, UCSF School of Medicine, San Francisco, CA, USA
| | - Jacob Eriksen
- Departments of Neurology and Physiology, UCSF School of Medicine, San Francisco, CA, USA
| | - Janet Finer-Moore
- Department of Biochemistry and Biophysics, University of California San Francisco (UCSF) School of Medicine, San Francisco, CA, USA
| | - Roger Chang
- Departments of Neurology and Physiology, UCSF School of Medicine, San Francisco, CA, USA.,Graduate Program in Biomedical Sciences, UCSF, San Francisco, CA, USA
| | - Phuong Nguyen
- Department of Biochemistry and Biophysics, University of California San Francisco (UCSF) School of Medicine, San Francisco, CA, USA
| | - Alisa Bowen
- Department of Biochemistry and Biophysics, University of California San Francisco (UCSF) School of Medicine, San Francisco, CA, USA
| | - Alexander Myasnikov
- Department of Biochemistry and Biophysics, University of California San Francisco (UCSF) School of Medicine, San Francisco, CA, USA
| | - Zanlin Yu
- Department of Biochemistry and Biophysics, University of California San Francisco (UCSF) School of Medicine, San Francisco, CA, USA
| | - David Bulkley
- Department of Biochemistry and Biophysics, University of California San Francisco (UCSF) School of Medicine, San Francisco, CA, USA
| | - Yifan Cheng
- Department of Biochemistry and Biophysics, University of California San Francisco (UCSF) School of Medicine, San Francisco, CA, USA.,Howard Hughes Medical Institute, UCSF, San Francisco, CA, USA
| | - Robert H Edwards
- Departments of Neurology and Physiology, UCSF School of Medicine, San Francisco, CA, USA.
| | - Robert M Stroud
- Department of Biochemistry and Biophysics, University of California San Francisco (UCSF) School of Medicine, San Francisco, CA, USA.
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52
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Wang YB, de Lartigue G, Page AJ. Dissecting the Role of Subtypes of Gastrointestinal Vagal Afferents. Front Physiol 2020; 11:643. [PMID: 32595525 PMCID: PMC7300233 DOI: 10.3389/fphys.2020.00643] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Accepted: 05/20/2020] [Indexed: 12/22/2022] Open
Abstract
Gastrointestinal (GI) vagal afferents convey sensory signals from the GI tract to the brain. Numerous subtypes of GI vagal afferent have been identified but their individual roles in gut function and feeding regulation are unclear. In the past decade, technical approaches to selectively target vagal afferent subtypes and to assess their function has significantly progressed. This review examines the classification of GI vagal afferent subtypes and discusses the current available techniques to study vagal afferents. Investigating the distribution of GI vagal afferent subtypes and understanding how to access and modulate individual populations are essential to dissect their fundamental roles in the gut-brain axis.
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Affiliation(s)
- Yoko B Wang
- Vagal Afferent Research Group, Adelaide Medical School, The University of Adelaide, Adelaide, SA, Australia
| | - Guillaume de Lartigue
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL, United States.,Center for Integrative Cardiovascular and Metabolic Disease, University of Florida, Gainesville, FL, United States
| | - Amanda J Page
- Vagal Afferent Research Group, Adelaide Medical School, The University of Adelaide, Adelaide, SA, Australia.,Nutrition, Diabetes and Gut Health, Lifelong Health Theme, South Australian Health and Medical Research Institute, Adelaide, SA, Australia
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53
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Pietrancosta N, Djibo M, Daumas S, El Mestikawy S, Erickson JD. Molecular, Structural, Functional, and Pharmacological Sites for Vesicular Glutamate Transporter Regulation. Mol Neurobiol 2020; 57:3118-3142. [PMID: 32474835 PMCID: PMC7261050 DOI: 10.1007/s12035-020-01912-7] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Accepted: 03/30/2020] [Indexed: 12/11/2022]
Abstract
Vesicular glutamate transporters (VGLUTs) control quantal size of glutamatergic transmission and have been the center of numerous studies over the past two decades. VGLUTs contain two independent transport modes that facilitate glutamate packaging into synaptic vesicles and phosphate (Pi) ion transport into the synaptic terminal. While a transmembrane proton electrical gradient established by a vacuolar-type ATPase powers vesicular glutamate transport, recent studies indicate that binding sites and flux properties for chloride, potassium, and protons within VGLUTs themselves regulate VGLUT activity as well. These intrinsic ionic binding and flux properties of VGLUTs can therefore be modulated by neurophysiological conditions to affect levels of glutamate available for release from synapses. Despite their extraordinary importance, specific and high-affinity pharmacological compounds that interact with these sites and regulate VGLUT function, distinguish between the various modes of transport, and the different isoforms themselves, are lacking. In this review, we provide an overview of the physiologic sites for VGLUT regulation that could modulate glutamate release in an over-active synapse or in a disease state.
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Affiliation(s)
- Nicolas Pietrancosta
- Neuroscience Paris Seine - Institut de Biologie Paris Seine (NPS - IBPS) INSERM, CNRS, Sorbonne Université, Paris, France. .,Laboratoire des Biomolécules, Sorbonne Université, CNRS, ENS, LBM, 75005, Paris, France.
| | - Mahamadou Djibo
- Sorbonne Paris Cité, Université Paris Descartes, LCBPT, UMR 8601, 75006, Paris, France
| | - Stephanie Daumas
- Neuroscience Paris Seine - Institut de Biologie Paris Seine (NPS - IBPS) INSERM, CNRS, Sorbonne Université, Paris, France
| | - Salah El Mestikawy
- Neuroscience Paris Seine - Institut de Biologie Paris Seine (NPS - IBPS) INSERM, CNRS, Sorbonne Université, Paris, France. .,Douglas Hospital Research Center, Department of Psychiatry, McGill University, 6875 boulevard Lasalle, Verdun, Montreal, QC, Canada.
| | - Jeffrey D Erickson
- Neuroscience Center, Louisiana State University, New Orleans, LA, 70112, USA. .,Department of Pharmacology, Louisiana State University, New Orleans, LA, 70112, USA.
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54
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Eriksen J, Li F, Edwards RH. The mechanism and regulation of vesicular glutamate transport: Coordination with the synaptic vesicle cycle. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183259. [PMID: 32147354 DOI: 10.1016/j.bbamem.2020.183259] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Revised: 03/02/2020] [Accepted: 03/02/2020] [Indexed: 01/30/2023]
Abstract
The transport of classical neurotransmitters into synaptic vesicles generally relies on a H+ electrochemical gradient (∆μH+). Synaptic vesicle uptake of glutamate depends primarily on the electrical component ∆ψ as the driving force, rather than the chemical component ∆pH. However, the vesicular glutamate transporters (VGLUTs) belong to the solute carrier 17 (SLC17) family, which includes closely related members that function as H+ cotransporters. Recent work has also shown that the VGLUTs undergo allosteric regulation by H+ and Cl-, and exhibit an associated Cl- conductance. These properties appear to coordinate VGLUT activity with the large ionic shifts that accompany the rapid recycling of synaptic vesicles driven by neural activity. Recent structural information also suggests common mechanisms that underlie the apparently divergent function of SLC17 family members, and that confer allosteric regulation.
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Affiliation(s)
- Jacob Eriksen
- Department of Physiology, UCSF School of Medicine, United States of America; Department of Neurology, UCSF School of Medicine, United States of America
| | - Fei Li
- Department of Physiology, UCSF School of Medicine, United States of America; Department of Neurology, UCSF School of Medicine, United States of America
| | - Robert H Edwards
- Department of Physiology, UCSF School of Medicine, United States of America; Department of Neurology, UCSF School of Medicine, United States of America.
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55
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Du X, Li J, Li M, Yang X, Qi Z, Xu B, Liu W, Xu Z, Deng Y. Research progress on the role of type I vesicular glutamate transporter (VGLUT1) in nervous system diseases. Cell Biosci 2020; 10:26. [PMID: 32158532 PMCID: PMC7057577 DOI: 10.1186/s13578-020-00393-4] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Accepted: 02/24/2020] [Indexed: 12/14/2022] Open
Abstract
Glutamate (Glu) is the predominant excitatory neurotransmitter in the central nervous system (CNS). Glutamatergic transmission is critical for controlling neuronal activity. In presynaptic neurons, Glu is stored in synaptic vesicles and released by stimulation. The homeostasis of glutamatergic system is maintained by a set of transporters in the membrane of synaptic vesicles. The family of vesicular Glu transporters in mammals is comprised of three highly homologous proteins: VGLUT1-3. Among them, VGLUT1 accounts for the largest proportion. However, most of the Glu is transported into the synaptic vesicles via the type 1 vesicle Glu transporter (VGLUT1). So, the expression of particular VGLUT1 is largely complementary with limited overlap and so far it is most specific markers for neurons that use Glu as neurotransmitter. Controlling the activity of VGLUT1 could potentially modulate the efficiency of excitatory neuro-transmission and change the filling level of synaptic vesicles. This review summarizes the recent knowledge concerning molecular and functional characteristic of VGLUT1, their development, contribution to a series of central nervous system and peripheral nervous system diseases such as learning and memory disorders, Alzheimer's disease, Parkinson's disease and sensitized nociception or pain pathology et al.
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Affiliation(s)
- Xianchao Du
- Department of Environmental Health, School of Public Health, China Medical University, Shenyang, 110122 Liaoning People’s Republic of China
| | - Jiashuo Li
- Department of Environmental Health, School of Public Health, China Medical University, Shenyang, 110122 Liaoning People’s Republic of China
| | - Minghui Li
- Department of Environmental Health, School of Public Health, China Medical University, Shenyang, 110122 Liaoning People’s Republic of China
| | - Xinxin Yang
- Department of Environmental Health, School of Public Health, China Medical University, Shenyang, 110122 Liaoning People’s Republic of China
| | - Zhipeng Qi
- Department of Environmental Health, School of Public Health, China Medical University, Shenyang, 110122 Liaoning People’s Republic of China
| | - Bin Xu
- Department of Environmental Health, School of Public Health, China Medical University, Shenyang, 110122 Liaoning People’s Republic of China
| | - Wei Liu
- Department of Environmental Health, School of Public Health, China Medical University, Shenyang, 110122 Liaoning People’s Republic of China
| | - Zhaofa Xu
- Department of Environmental Health, School of Public Health, China Medical University, Shenyang, 110122 Liaoning People’s Republic of China
| | - Yu Deng
- Department of Environmental Health, School of Public Health, China Medical University, Shenyang, 110122 Liaoning People’s Republic of China
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56
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VGLUT2/Cdk5/p25 Signaling Pathway Contributed to Inflammatory Pain by Complete Freund's Adjuvant. Pain Res Manag 2020; 2020:4807674. [PMID: 32190166 PMCID: PMC7066405 DOI: 10.1155/2020/4807674] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Revised: 01/09/2020] [Accepted: 01/16/2020] [Indexed: 01/28/2023]
Abstract
Vesicular glutamate transporter type 2 (VGLUT2) is known to play an important role in mediating heat hyperalgesia induced by inflammation. However, the underlying mechanism for this activity is poorly understood. Cyclin-dependent kinase 5 (Cdk5), serving as a key regulator in modulating release of glutamate, acted a key player in the formation of heat hyperalgesia of inflammatory pain. However, it remains unknown whether there is a bridge between Cdk5 and VGLUT2 for mediating inflammatory pain. Therefore, we designed the experiment to determine whether VGLUT2 signaling pathway is involved in inflammatory pain mediated by Cdk5 in the inflammatory pain model induced by complete Freund's adjuvant (CFA). Our results showed that the coexpression of Cdk5/VGLUT2 in small- and medium-sized neuronal cells of the dorsal root ganglion (DRG) and spinal cord between days 1 and 3 following subcutaneous injection of CFA was significantly increased. Moreover, our study revealed that the expression of VGLUT2 protein in the DRG and spinal cord was remarkably increased between days 1 and 3 following CFA injection and was significantly reduced by roscovitine, a selective antagonist of Cdk5. Additionally, p25 but not p35, an activator of Cdk5, protein was significantly increased by CFA and reduced by roscovitine. Our findings suggested that VGLUT2/Cdk5 signaling pathway contributes to inflammatory pain mediated by Cdk5/p25.
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57
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Dong C, Li F, Yang T, Feng L, Zhang S, Li F, Li W, Xu G, Bao S, Wan X, Lucas WJ, Zhang Z. Theanine transporters identified in tea plants (Camellia sinensis L.). THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 101:57-70. [PMID: 31461558 DOI: 10.1111/tpj.14517] [Citation(s) in RCA: 69] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2019] [Revised: 08/12/2019] [Accepted: 08/19/2019] [Indexed: 05/07/2023]
Abstract
Theanine, a unique non-proteinogenic amino acid, is an important component of tea, as it confers the umami taste and relaxation effect of tea as a beverage. Theanine is primarily synthesized in tea roots and is subsequently transported to young shoots, which are harvested for tea production. Currently, the mechanism for theanine transport in the tea plant remains unknown. Here, by screening a yeast mutant library, followed by functional analyses, we identified the glutamine permease, GNP1 as a specific transporter for theanine in yeast. Although there is no GNP1 homolog in the tea plant, we assessed the theanine transport ability of nine tea plant amino acid permease (AAP) family members, with six exhibiting transport activity. We further determined that CsAAP1, CsAAP2, CsAAP4, CsAAP5, CsAAP6, and CsAAP8 exhibited moderate theanine affinities and transport was H+ -dependent. The tissue-specific expression of these six CsAAPs in leaves, vascular tissues, and the root suggested their broad roles in theanine loading and unloading from the vascular system, and in targeting to sink tissues. Furthermore, expression of these CsAAPs was shown to be seasonally regulated, coincident with theanine transport within the tea plant. Finally, CsAAP1 expression in the root was highly correlated with root-to-bud transport of theanine, in seven tea plant cultivars. Taken together, these findings support the hypothesis that members of the CsAAP family transport theanine and participate in its root-to-shoot delivery in the tea plant.
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Affiliation(s)
- Chunxia Dong
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, 230036, China
| | - Fang Li
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, 230036, China
| | - Tianyuan Yang
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, 230036, China
| | - Lin Feng
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, 230036, China
| | - Shupei Zhang
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, 230036, China
| | - Fangdong Li
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, 230036, China
| | - Weihong Li
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing, 210095, China
| | - Guohua Xu
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing, 210095, China
| | - Shilai Bao
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, 230036, China
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Xiaochun Wan
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, 230036, China
| | - William J Lucas
- Department of Plant Biology, College of Biological Sciences, University of California, Davis, CA, 95616, USA
| | - Zhaoliang Zhang
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, 230036, China
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58
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Root DH, Zhang S, Barker DJ, Miranda-Barrientos J, Liu B, Wang HL, Morales M. Selective Brain Distribution and Distinctive Synaptic Architecture of Dual Glutamatergic-GABAergic Neurons. Cell Rep 2019; 23:3465-3479. [PMID: 29924991 DOI: 10.1016/j.celrep.2018.05.063] [Citation(s) in RCA: 96] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2017] [Revised: 04/13/2018] [Accepted: 05/17/2018] [Indexed: 10/28/2022] Open
Abstract
For decades, it has been thought that glutamate and GABA are released by distinct neurons. However, some mouse neurons innervating the lateral habenula (LHb) co-release glutamate and GABA. Here, we mapped the distribution of neurons throughout the rat brain that co-express vesicular transporters for the accumulation of glutamate (VGluT2) or GABA (VGaT) and for GABA synthesis (GAD). We found concentrated groups of neurons that co-express VGluT2, VGaT, and GAD mRNAs within subdivisions of the ventral tegmental area (VTA), entopeduncular (EPN), and supramammillary (SUM) nuclei. Single axon terminals established by VTA, EPN, or SUM neurons form a common synaptic architecture involving asymmetric (putative excitatory) and symmetric (putative inhibitory) synapses. Within the LHb, which receives co-transmitted glutamate and GABA from VTA and EPN, VGluT2 and VGaT are distributed on separate synaptic vesicles. We conclude that single axon terminals from VGluT2 and VGaT co-expressing neurons co-transmit glutamate and GABA from distinct synaptic vesicles at independent synapses.
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Affiliation(s)
- David H Root
- Neuronal Networks Section, Integrative Neuroscience Research Branch, National Institute on Drug Abuse, 251 Bayview Blvd., Suite 200, Baltimore, MD 21224, USA
| | - Shiliang Zhang
- Electron Microscopy Core, National Institute on Drug Abuse, 251 Bayview Blvd., Suite 200, Baltimore, MD 21224, USA
| | - David J Barker
- Neuronal Networks Section, Integrative Neuroscience Research Branch, National Institute on Drug Abuse, 251 Bayview Blvd., Suite 200, Baltimore, MD 21224, USA
| | - Jorge Miranda-Barrientos
- Neuronal Networks Section, Integrative Neuroscience Research Branch, National Institute on Drug Abuse, 251 Bayview Blvd., Suite 200, Baltimore, MD 21224, USA
| | - Bing Liu
- Neuronal Networks Section, Integrative Neuroscience Research Branch, National Institute on Drug Abuse, 251 Bayview Blvd., Suite 200, Baltimore, MD 21224, USA
| | - Hui-Ling Wang
- Neuronal Networks Section, Integrative Neuroscience Research Branch, National Institute on Drug Abuse, 251 Bayview Blvd., Suite 200, Baltimore, MD 21224, USA
| | - Marisela Morales
- Neuronal Networks Section, Integrative Neuroscience Research Branch, National Institute on Drug Abuse, 251 Bayview Blvd., Suite 200, Baltimore, MD 21224, USA.
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59
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Bimpisidis Z, Wallén-Mackenzie Å. Neurocircuitry of Reward and Addiction: Potential Impact of Dopamine-Glutamate Co-release as Future Target in Substance Use Disorder. J Clin Med 2019; 8:E1887. [PMID: 31698743 PMCID: PMC6912639 DOI: 10.3390/jcm8111887] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Revised: 10/29/2019] [Accepted: 11/01/2019] [Indexed: 12/21/2022] Open
Abstract
Dopamine-glutamate co-release is a unique property of midbrain neurons primarily located in the ventral tegmental area (VTA). Dopamine neurons of the VTA are important for behavioral regulation in response to rewarding substances, including natural rewards and addictive drugs. The impact of glutamate co-release on behaviors regulated by VTA dopamine neurons has been challenging to probe due to lack of selective methodology. However, several studies implementing conditional knockout and optogenetics technologies in transgenic mice have during the past decade pointed towards a role for glutamate co-release in multiple physiological and behavioral processes of importance to substance use and abuse. In this review, we discuss these studies to highlight findings that may be critical when considering mechanisms of importance for prevention and treatment of substance abuse.
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60
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Zhang XM, François U, Silm K, Angelo MF, Fernandez-Busch MV, Maged M, Martin C, Bernard V, Cordelières FP, Deshors M, Pons S, Maskos U, Bemelmans AP, Wojcik SM, El Mestikawy S, Humeau Y, Herzog E. A proline-rich motif on VGLUT1 reduces synaptic vesicle super-pool and spontaneous release frequency. eLife 2019; 8:50401. [PMID: 31663854 PMCID: PMC6861006 DOI: 10.7554/elife.50401] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Accepted: 10/27/2019] [Indexed: 12/29/2022] Open
Abstract
Glutamate secretion at excitatory synapses is tightly regulated to allow for the precise tuning of synaptic strength. Vesicular Glutamate Transporters (VGLUT) accumulate glutamate into synaptic vesicles (SV) and thereby regulate quantal size. Further, the number of release sites and the release probability of SVs maybe regulated by the organization of active-zone proteins and SV clusters. In the present work, we uncover a mechanism mediating an increased SV clustering through the interaction of VGLUT1 second proline-rich domain, endophilinA1 and intersectin1. This strengthening of SV clusters results in a combined reduction of axonal SV super-pool size and miniature excitatory events frequency. Our findings support a model in which clustered vesicles are held together through multiple weak interactions between Src homology three and proline-rich domains of synaptic proteins. In mammals, VGLUT1 gained a proline-rich sequence that recruits endophilinA1 and turns the transporter into a regulator of SV organization and spontaneous release.
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Affiliation(s)
- Xiao Min Zhang
- Interdisciplinary Institute for Neuroscience, Université de Bordeaux, Bordeaux, France.,Interdisciplinary Institute for Neuroscience CNRS UMR 5297, Bordeaux, France.,Department of Molecular Neurobiology, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Urielle François
- Interdisciplinary Institute for Neuroscience, Université de Bordeaux, Bordeaux, France.,Interdisciplinary Institute for Neuroscience CNRS UMR 5297, Bordeaux, France
| | - Kätlin Silm
- Neuroscience Paris Seine NPS, Université Pierre et Marie Curie INSERM U1130 CNRS UMR8246, Paris, France
| | - Maria Florencia Angelo
- Interdisciplinary Institute for Neuroscience, Université de Bordeaux, Bordeaux, France.,Interdisciplinary Institute for Neuroscience CNRS UMR 5297, Bordeaux, France
| | - Maria Victoria Fernandez-Busch
- Interdisciplinary Institute for Neuroscience, Université de Bordeaux, Bordeaux, France.,Interdisciplinary Institute for Neuroscience CNRS UMR 5297, Bordeaux, France
| | - Mona Maged
- Interdisciplinary Institute for Neuroscience, Université de Bordeaux, Bordeaux, France.,Interdisciplinary Institute for Neuroscience CNRS UMR 5297, Bordeaux, France
| | - Christelle Martin
- Interdisciplinary Institute for Neuroscience, Université de Bordeaux, Bordeaux, France.,Interdisciplinary Institute for Neuroscience CNRS UMR 5297, Bordeaux, France
| | - Véronique Bernard
- Neuroscience Paris Seine NPS, Université Pierre et Marie Curie INSERM U1130 CNRS UMR8246, Paris, France
| | - Fabrice P Cordelières
- Bordeaux Imaging Center, Université de Bordeaux, CNRS UMS 3420, INSERM US4, Bordeaux, France
| | - Melissa Deshors
- Interdisciplinary Institute for Neuroscience, Université de Bordeaux, Bordeaux, France.,Interdisciplinary Institute for Neuroscience CNRS UMR 5297, Bordeaux, France
| | - Stéphanie Pons
- Institut Pasteur, CNRS UMR 3571, Unité NISC, Paris, France
| | - Uwe Maskos
- Institut Pasteur, CNRS UMR 3571, Unité NISC, Paris, France
| | - Alexis Pierre Bemelmans
- Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA), Direction de laRecherche Fondamentale (DRF), Institut de Biologie François Jacob (IBFJ), MolecularImaging Research Center (MIRCen), Fontenay-aux-Roses, France
| | - Sonja M Wojcik
- Department of Molecular Neurobiology, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Salah El Mestikawy
- Neuroscience Paris Seine NPS, Université Pierre et Marie Curie INSERM U1130 CNRS UMR8246, Paris, France.,Department of Psychiatry, Douglas Mental Health University Institute, McGill University, Montreal, Canada
| | - Yann Humeau
- Interdisciplinary Institute for Neuroscience, Université de Bordeaux, Bordeaux, France.,Interdisciplinary Institute for Neuroscience CNRS UMR 5297, Bordeaux, France
| | - Etienne Herzog
- Interdisciplinary Institute for Neuroscience, Université de Bordeaux, Bordeaux, France.,Interdisciplinary Institute for Neuroscience CNRS UMR 5297, Bordeaux, France
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61
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Separate vmPFC Ensembles Control Cocaine Self-Administration Versus Extinction in Rats. J Neurosci 2019; 39:7394-7407. [PMID: 31331999 DOI: 10.1523/jneurosci.0918-19.2019] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 07/02/2019] [Accepted: 07/09/2019] [Indexed: 01/06/2023] Open
Abstract
Recent studies suggest that the ventral medial prefrontal cortex (vmPFC) encodes both operant drug self-administration and extinction memories. Here, we examined whether these opposing memories are encoded by distinct neuronal ensembles within the vmPFC with different outputs to the nucleus accumbens (NAc) in male and female rats. Using cocaine self-administration (3 h/d for 14 d) and extinction procedures, we demonstrated that vmPFC was similarly activated (indexed by Fos) during cocaine-seeking tests after 0 (no-extinction) or 7 extinction sessions. Selective Daun02 lesioning of the self-administration ensemble (no-extinction) decreased cocaine seeking, whereas Daun02 lesioning of the extinction ensemble increased cocaine seeking. Retrograde tracing with fluorescent cholera toxin subunit B injected into NAc combined with Fos colabeling in vmPFC indicated that vmPFC self-administration ensembles project to NAc core while extinction ensembles project to NAc shell. Functional disconnection experiments (Daun02 lesioning of vmPFC and acute dopamine D1-receptor blockade with SCH39166 in NAc core or shell) confirm that vmPFC ensembles interact with NAc core versus shell to play dissociable roles in cocaine self-administration versus extinction, respectively. Our results demonstrate that neuronal ensembles mediating cocaine self-administration and extinction comingle in vmPFC but have distinct outputs to the NAc core and shell that promote or inhibit cocaine seeking.SIGNIFICANCE STATEMENT Neuronal ensembles within the vmPFC have recently been shown to play a role in self-administration and extinction of food seeking. Here, we used the Daun02 chemogenetic inactivation procedure, which allows selective inhibition of neuronal ensembles identified by the activity marker Fos, to demonstrate that different ensembles for cocaine self-administration and extinction memories coexist in the ventral mPFC and interact with distinct subregions of the nucleus accumbens.
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Katz M, Corson F, Keil W, Singhal A, Bae A, Lu Y, Liang Y, Shaham S. Glutamate spillover in C. elegans triggers repetitive behavior through presynaptic activation of MGL-2/mGluR5. Nat Commun 2019; 10:1882. [PMID: 31015396 PMCID: PMC6478929 DOI: 10.1038/s41467-019-09581-4] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Accepted: 03/20/2019] [Indexed: 01/08/2023] Open
Abstract
Glutamate is a major excitatory neurotransmitter, and impaired glutamate clearance following synaptic release promotes spillover, inducing extra-synaptic signaling. The effects of glutamate spillover on animal behavior and its neural correlates are poorly understood. We developed a glutamate spillover model in Caenorhabditis elegans by inactivating the conserved glial glutamate transporter GLT-1. GLT-1 loss drives aberrant repetitive locomotory reversal behavior through uncontrolled oscillatory release of glutamate onto AVA, a major interneuron governing reversals. Repetitive glutamate release and reversal behavior require the glutamate receptor MGL-2/mGluR5, expressed in RIM and other interneurons presynaptic to AVA. mgl-2 loss blocks oscillations and repetitive behavior; while RIM activation is sufficient to induce repetitive reversals in glt-1 mutants. Repetitive AVA firing and reversals require EGL-30/Gαq, an mGluR5 effector. Our studies reveal that cyclic autocrine presynaptic activation drives repetitive reversals following glutamate spillover. That mammalian GLT1 and mGluR5 are implicated in pathological motor repetition suggests a common mechanism controlling repetitive behaviors. Katz and colleagues examine glutamate spillover effects on C. elegans behaviour. They show that impaired synaptic glutamate clearance in glial glutamate transporter mutants, causes presynaptic mgl-2/mGluR5 activation, generating postsynaptic neural activity oscillations driving repetitive behaviour.
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Affiliation(s)
- Menachem Katz
- Laboratory of Developmental Genetics, The Rockefeller University, 1230 York Avenue, New York, NY, 10065, USA
| | - Francis Corson
- Laboratoire de Physique Statistique, Ecole Normale Supérieure, CNRS, Université Pierre et Marie Curie, Université Paris Diderot, 75005, Paris, France
| | - Wolfgang Keil
- Laboratory of Developmental Genetics, The Rockefeller University, 1230 York Avenue, New York, NY, 10065, USA.,Center for Studies in Physics and Biology, The Rockefeller University, 1230 York Avenue, New York, NY, 10065, USA
| | - Anupriya Singhal
- Laboratory of Developmental Genetics, The Rockefeller University, 1230 York Avenue, New York, NY, 10065, USA
| | - Andrea Bae
- Laboratory of Developmental Genetics, The Rockefeller University, 1230 York Avenue, New York, NY, 10065, USA
| | - Yun Lu
- Laboratory of Developmental Genetics, The Rockefeller University, 1230 York Avenue, New York, NY, 10065, USA
| | - Yupu Liang
- Research Bioinformatics, The Rockefeller University, 1230 York Avenue, New York, NY, 10065, USA
| | - Shai Shaham
- Laboratory of Developmental Genetics, The Rockefeller University, 1230 York Avenue, New York, NY, 10065, USA.
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63
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Amino acid transporters in the regulation of insulin secretion and signalling. Biochem Soc Trans 2019; 47:571-590. [PMID: 30936244 DOI: 10.1042/bst20180250] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 02/24/2019] [Accepted: 02/25/2019] [Indexed: 01/02/2023]
Abstract
Amino acids are increasingly recognised as modulators of nutrient disposal, including their role in regulating blood glucose through interactions with insulin signalling. More recently, cellular membrane transporters of amino acids have been shown to form a pivotal part of this regulation as they are primarily responsible for controlling cellular and circulating amino acid concentrations. The availability of amino acids regulated by transporters can amplify insulin secretion and modulate insulin signalling in various tissues. In addition, insulin itself can regulate the expression of numerous amino acid transporters. This review focuses on amino acid transporters linked to the regulation of insulin secretion and signalling with a focus on those of the small intestine, pancreatic β-islet cells and insulin-responsive tissues, liver and skeletal muscle. We summarise the role of the amino acid transporter B0AT1 (SLC6A19) and peptide transporter PEPT1 (SLC15A1) in the modulation of global insulin signalling via the liver-secreted hormone fibroblast growth factor 21 (FGF21). The role of vesicular vGLUT (SLC17) and mitochondrial SLC25 transporters in providing glutamate for the potentiation of insulin secretion is covered. We also survey the roles SNAT (SLC38) family and LAT1 (SLC7A5) amino acid transporters play in the regulation of and by insulin in numerous affective tissues. We hypothesise the small intestine amino acid transporter B0AT1 represents a crucial nexus between insulin, FGF21 and incretin hormone signalling pathways. The aim is to give an integrated overview of the important role amino acid transporters have been found to play in insulin-regulated nutrient signalling.
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64
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Expression of plasma membrane calcium ATPases confers Ca 2+/H + exchange in rodent synaptic vesicles. Sci Rep 2019; 9:4289. [PMID: 30862855 PMCID: PMC6414521 DOI: 10.1038/s41598-019-40557-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Accepted: 02/19/2019] [Indexed: 02/07/2023] Open
Abstract
Ca2+ transport into synaptic vesicles (SVs) at the presynaptic terminals has been proposed to be an important process for regulating presynaptic [Ca2+] during stimulation as well as at rest. However, the molecular identity of the transport system remains elusive. Previous studies have demonstrated that isolated SVs exhibit two distinct Ca2+ transport systems depending on extra-vesicular (cytosolic) pH; one is mediated by a high affinity Ca2+ transporter which is active at neutral pH and the other is mediated by a low affinity Ca2+/H+ antiporter which is maximally active at alkaline pH of 8.5. In addition, synaptic vesicle glycoprotein 2 s (SV2s), a major SV component, have been proposed to contribute to Ca2+ clearance from the presynaptic cytoplasm. Here, we show that at physiological pH, the plasma membrane Ca2+ ATPases (PMCAs) are responsible for both the Ca2+/H+ exchange activity and Ca2+ uptake into SVs. The Ca2+/H+ exchange activity monitored by acidification assay exhibited high affinity for Ca2+ (Km ~ 400 nM) and characteristic divalent cation selectivity for the PMCAs. Both activities were remarkably reduced by PMCA blockers, but not by a blocker of the ATPase that transfers Ca2+ from the cytosol to the lumen of sarcoplasmic endoplasmic reticulum (SERCA) at physiological pH. Furthermore, we rule out the contribution of SV2s, putative Ca2+ transporters on SVs, since both Ca2+/H+ exchange activity and Ca2+ transport were unaffected in isolated vesicles derived from SV2-deficient brains. Finally, using a PMCA1-pHluorin construct that enabled us to monitor cellular distribution and recycling properties in living neurons, we demonstrated that PMCA1-pHluorin localized to intracellular acidic compartments and recycled at presynaptic terminals in an activity-dependent manner. Collectively, our results imply that vesicular PMCAs may play pivotal roles in both presynaptic Ca2+ homeostasis and the modulation of H+ gradient in SVs.
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65
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Water-soluble CoQ10 as A Promising Anti-aging Agent for Neurological Dysfunction in Brain Mitochondria. Antioxidants (Basel) 2019; 8:antiox8030061. [PMID: 30862106 PMCID: PMC6466529 DOI: 10.3390/antiox8030061] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 02/19/2019] [Accepted: 03/08/2019] [Indexed: 11/17/2022] Open
Abstract
Mitochondrial function has been closely associated with normal aging and age-related diseases. Age-associated declines in mitochondrial function, such as changes in oxygen consumption rate, cytochrome c oxidase activity of complex IV, and mitochondrial coenzyme Q (CoQ) levels, begin as early as 12 to 15 months of age in male mouse brains. Brain mitochondrial dysfunction is accompanied by increased accumulation of phosphorylated α-synuclein in the motor cortex and impairment of motor activities, which are similar characteristics of Parkinson's disease. However, these age-associated defects are completely rescued by the administration of exogenous CoQ10 to middle-aged mice via its water solubilization by emulsification in drinking water. Further efforts to develop strategies to enhance the biological availability of CoQ10 to successfully ameliorate age-related brain mitochondrial dysfunction or neurodegenerative disorders may provide a promising anti-aging agent.
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66
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Kinetic Measurements of Endocytosis and Exocytosis in Cultured Neurons. Methods Mol Biol 2019. [PMID: 30771167 DOI: 10.1007/978-1-4939-9124-2_3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
The measurement of synaptic vesicle recycling in live neurons transfected with vesicular glutamate transporter fused to pHluorin (vGLUT-pHluorin) allows us to study exocytosis and endocytosis in neurons. When neurons are transfected with this protein we can measure the rate of vesicles fusing and internalizing from the membrane using live total internal reflection fluorescence (TIRF) imaging. Here, we describe transfection, culturing, and imaging of wild-type and αβγ-synuclein knockout hippocampal neurons. This technique can be used to evaluate the effect of different phenotypes and treatments in the physiology of synaptic vesicle recycling in cultured neurons.
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67
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Hannou L, Roy P, Ballester Roig MN, Mongrain V. Transcriptional control of synaptic components by the clock machinery. Eur J Neurosci 2019; 51:241-267. [DOI: 10.1111/ejn.14294] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Revised: 11/01/2018] [Accepted: 11/27/2018] [Indexed: 12/21/2022]
Affiliation(s)
- Lydia Hannou
- Center for Advanced Research in Sleep Medicine and Research CenterHôpital du Sacré‐Cœur de Montréal (CIUSSS‐NIM) Montreal Quebec Canada
- Department of PsychiatryUniversité de Montréal Montreal Quebec Canada
| | - Pierre‐Gabriel Roy
- Center for Advanced Research in Sleep Medicine and Research CenterHôpital du Sacré‐Cœur de Montréal (CIUSSS‐NIM) Montreal Quebec Canada
- Department of NeuroscienceUniversité de Montréal Montreal Quebec Canada
| | - Maria Neus Ballester Roig
- Center for Advanced Research in Sleep Medicine and Research CenterHôpital du Sacré‐Cœur de Montréal (CIUSSS‐NIM) Montreal Quebec Canada
- Department of NeuroscienceUniversité de Montréal Montreal Quebec Canada
| | - Valérie Mongrain
- Center for Advanced Research in Sleep Medicine and Research CenterHôpital du Sacré‐Cœur de Montréal (CIUSSS‐NIM) Montreal Quebec Canada
- Department of NeuroscienceUniversité de Montréal Montreal Quebec Canada
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68
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TAKAHASHI H, YOKOI N, SEINO S. Glutamate as intracellular and extracellular signals in pancreatic islet functions. PROCEEDINGS OF THE JAPAN ACADEMY. SERIES B, PHYSICAL AND BIOLOGICAL SCIENCES 2019; 95:246-260. [PMID: 31189778 PMCID: PMC6751295 DOI: 10.2183/pjab.95.017] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 03/08/2019] [Indexed: 05/25/2023]
Abstract
l-Glutamate is one of the most abundant amino acids in the body and is a constituent of proteins and a substrate in metabolism. It is well known that glutamate serves as a primary excitatory neurotransmitter and a critical neuromodulator in the brain. Recent studies have shown that in addition to its pivotal role in neural functions, glutamate plays many important roles in a variety of cellular functions, including those as intracellular and extracellular signals. In pancreatic islets, glutamate is now known to be required for the normal regulation of insulin secretion, such as incretin-induced insulin secretion. In this review, we primarily discuss the physiological and pathophysiological roles of glutamate as intracellular and extracellular signals in the functions of pancreatic islets.
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Affiliation(s)
- Harumi TAKAHASHI
- Division of Molecular and Metabolic Medicine, Department of Physiology and Cell Biology, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan
| | - Norihide YOKOI
- Division of Molecular and Metabolic Medicine, Department of Physiology and Cell Biology, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan
| | - Susumu SEINO
- Division of Molecular and Metabolic Medicine, Department of Physiology and Cell Biology, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan
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69
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Trudeau LE, El Mestikawy S. Glutamate Cotransmission in Cholinergic, GABAergic and Monoamine Systems: Contrasts and Commonalities. Front Neural Circuits 2018; 12:113. [PMID: 30618649 PMCID: PMC6305298 DOI: 10.3389/fncir.2018.00113] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Accepted: 12/03/2018] [Indexed: 11/13/2022] Open
Abstract
Multiple discoveries made since the identification of vesicular glutamate transporters (VGLUTs) two decades ago revealed that many neuronal populations in the brain use glutamate in addition to their "primary" neurotransmitter. Such a mode of cotransmission has been detected in dopamine (DA), acetylcholine (ACh), serotonin (5-HT), norepinephrine (NE) and surprisingly even in GABA neurons. Interestingly, work performed by multiple groups during the past decade suggests that the use of glutamate as a cotransmitter takes different forms in these different populations of neurons. In the present review, we will provide an overview of glutamate cotransmission in these different classes of neurons, highlighting puzzling differences in: (1) the proportion of such neurons expressing a VGLUT in different brain regions and at different stages of development; (2) the sub-cellular localization of the VGLUT; (3) the localization of the VGLUT in relation to the neurons' other vesicular transporter; and (4) the functional role of glutamate cotransmission.
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Affiliation(s)
- Louis-Eric Trudeau
- CNS Research Group, Department of Pharmacology and Physiology, Department of Neurosciences, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada
| | - Salah El Mestikawy
- Department of Psychiatry, Faculty of Medicine, Douglas Mental Health University Institute, McGill University, Montreal, QC, Canada.,Sorbonne Universités, Université Pierre et Marie Curie UM 119-CNRS UMR 8246-INSERM U1130, Neurosciences Paris Seine-Institut de Biologie Paris Seine (NPS-IBPS), Paris, France
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70
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Perez SM, Lodge DJ. Convergent Inputs from the Hippocampus and Thalamus to the Nucleus Accumbens Regulate Dopamine Neuron Activity. J Neurosci 2018; 38:10607-10618. [PMID: 30355626 PMCID: PMC6290296 DOI: 10.1523/jneurosci.2629-16.2018] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Revised: 09/21/2018] [Accepted: 09/22/2018] [Indexed: 01/12/2023] Open
Abstract
Aberrant hippocampal activity is observed in individuals with schizophrenia and is thought to underlie the augmented dopamine system function associated with psychosis. The pathway by which the ventral hippocampus (vHipp) regulates dopamine neuron activity has been demonstrated previously and involves a glutamatergic projection to the nucleus accumbens (NAc). Recent postmortem studies have confirmed glutamatergic abnormalities in the NAc of individuals with schizophrenia. Specifically, an increase in vesicular glutamate transporter 2 (vGlut2) expression was reported. Although projections from the hippocampus do express vGlut2, inputs from the thalamus are more likely to account for this alteration; however, the role of thalamic inputs to the NAc in the regulation of dopamine neuron activity has not been elucidated. Here, using male Sprague Dawley rats, we demonstrate that a subset of NAc medium spiny neurons receive convergent inputs from the vHipp and paraventricular nucleus of the thalamus (PVT), with both regions working synergistically to regulate dopamine neuron activity. Activation of either the vHipp or PVT increases the number of spontaneously active dopamine neurons in the ventral tegmental area. Moreover, this regulation requires simultaneous activity in both regions because PVT inactivation can reverse vHipp-induced increases in dopamine neuron population activity and vHipp inactivation can reverse PVT-induced increases. This is relevant to schizophrenia because inactivation of either the vHipp or PVT is sufficient to reverse aberrant dopamine system function in two distinct rodent models. These data suggest that thalamic abnormalities may contribute to the aberrant dopamine system function observed in schizophrenia and that the PVT represents a novel site of intervention for psychosis.SIGNIFICANCE STATEMENT Current treatments for schizophrenia are far from adequate and a more complete understanding of the pathophysiology underlying this disease is warranted if we are to discover novel therapeutic targets. We have previously demonstrated that the aberrant dopamine system function observed in individuals with schizophrenia and rodent models is driven by increases in hippocampal activity. We now demonstrate that thalamic (paraventricular nucleus, PVT) and ventral hippocampal afferents converge in the nucleus accumbens to regulate dopamine system function. Such information provides a potential site for therapeutic intervention for schizophrenia. Indeed, inactivation of the PVT can effectively reverse aberrant dopamine system function in two distinct rodent models displaying circuit level alterations and corresponding behavioral deficits relevant to schizophrenia.
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Affiliation(s)
- Stephanie M Perez
- Department of Pharmacology and Center for Biomedical Neuroscience, University of Texas Health Science Center, San Antonio, Texas 78229
| | - Daniel J Lodge
- Department of Pharmacology and Center for Biomedical Neuroscience, University of Texas Health Science Center, San Antonio, Texas 78229
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71
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Development of lentiviral vectors for efficient glutamatergic-selective gene expression in cultured hippocampal neurons. Sci Rep 2018; 8:15156. [PMID: 30310105 PMCID: PMC6181963 DOI: 10.1038/s41598-018-33509-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Accepted: 10/01/2018] [Indexed: 01/11/2023] Open
Abstract
Targeting gene expression to a particular subset of neurons helps study the cellular function of the nervous system. Although neuron-specific promoters, such as the synapsin I promoter and the α-CaMKII promoter, are known to exhibit selectivity for excitatory glutamatergic neurons in vivo, the cell type-specificity of these promoters has not been thoroughly tested in culture preparations. Here, by using hippocampal culture preparation from the VGAT-Venus transgenic mice, we examined the ability of five putative promoter sequences of glutamatergic-selective markers including synapsin I, α-CaMKII, the vesicular glutamate transporter 1 (VGLUT1), Dock10 and Prox1. Among these, a genomic fragment containing a 2.1 kb segment upstream of the translation start site (TSS) of the VGLUT1 implemented in a lentiviral vector with the Tet-Off inducible system achieved the highest preferential gene expression in glutamatergic neurons. Analysis of various lengths of the VGLUT1 promoter regions identified a segment between −2.1 kb and −1.4 kb from the TSS as a responsible element for the glutamatergic selectivity. Consistently, expression of channelrhodopsin under this promoter sequence allowed for selective light-evoked activation of excitatory neurons. Thus, the lentiviral system carrying the VGLUT1 promoter fragment can be used to effectively target exogenous gene expression to excitatory glutamatergic neurons in cultures.
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72
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Zhang FX, Ge SN, Dong YL, Shi J, Feng YP, Li Y, Li YQ, Li JL. Vesicular glutamate transporter isoforms: The essential players in the somatosensory systems. Prog Neurobiol 2018; 171:72-89. [PMID: 30273635 DOI: 10.1016/j.pneurobio.2018.09.006] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 08/28/2018] [Accepted: 09/23/2018] [Indexed: 02/08/2023]
Abstract
In nervous system, glutamate transmission is crucial for centripetal conveyance and cortical perception of sensory signals of different modalities, which necessitates vesicular glutamate transporters 1-3 (VGLUT 1-3), the three homologous membrane-bound protein isoforms, to load glutamate into the presysnaptic vesicles. These VGLUTs, especially VGLUT1 and VGLUT2, selectively label and define functionally distinct neuronal subpopulations at each relay level of the neural hierarchies comprising spinal and trigeminal sensory systems. In this review, by scrutinizing each structure of the organism's fundamental hierarchies including dorsal root/trigeminal ganglia, spinal dorsal horn/trigeminal sensory nuclear complex, somatosensory thalamic nuclei and primary somatosensory cortex, we summarize and characterize in detail within each relay the neuronal clusters expressing distinct VGLUT protein/transcript isoforms, with respect to their regional distribution features (complementary distribution in some structures), axonal terminations/peripheral innervations and physiological functions. Equally important, the distribution pattern and characteristics of VGLUT1/VGLUT2 axon terminals within these structures are also epitomized. Finally, the correlation of a particular VGLUT isoform and its physiological role, disclosed thus far largely via studying the peripheral receptors, is generalized by referring to reports on global and conditioned VGLUT-knockout mice. Also, researches on VGLUTs relating to future direction are tentatively proposed, such as unveiling the elusive differences between distinct VGLUTs in mechanism and/or pharmacokinetics at ionic/molecular level, and developing VGLUT-based pain killers.
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Affiliation(s)
- Fu-Xing Zhang
- Department of Anatomy and K.K. Leung Brain Research Centre, School of Basic Medicine, The Fourth Military Medical University, Xi'an 710032, PR China
| | - Shun-Nan Ge
- Department of Anatomy and K.K. Leung Brain Research Centre, School of Basic Medicine, The Fourth Military Medical University, Xi'an 710032, PR China; Department of Neurosurgery, Tangdu Hospital, The Fourth Military Medical University, Xi'an 710038, PR China
| | - Yu-Lin Dong
- Department of Anatomy and K.K. Leung Brain Research Centre, School of Basic Medicine, The Fourth Military Medical University, Xi'an 710032, PR China
| | - Juan Shi
- Department of Anatomy and K.K. Leung Brain Research Centre, School of Basic Medicine, The Fourth Military Medical University, Xi'an 710032, PR China
| | - Yu-Peng Feng
- Department of Anatomy and K.K. Leung Brain Research Centre, School of Basic Medicine, The Fourth Military Medical University, Xi'an 710032, PR China
| | - Yang Li
- Department of Neurosurgery, Tangdu Hospital, The Fourth Military Medical University, Xi'an 710038, PR China
| | - Yun-Qing Li
- Department of Anatomy and K.K. Leung Brain Research Centre, School of Basic Medicine, The Fourth Military Medical University, Xi'an 710032, PR China; Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200032, PR China.
| | - Jin-Lian Li
- Department of Anatomy and K.K. Leung Brain Research Centre, School of Basic Medicine, The Fourth Military Medical University, Xi'an 710032, PR China.
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73
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Direct imaging of uncoated biological samples enables correlation of super-resolution and electron microscopy data. Sci Rep 2018; 8:11610. [PMID: 30072703 PMCID: PMC6072772 DOI: 10.1038/s41598-018-29970-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Accepted: 07/23/2018] [Indexed: 11/08/2022] Open
Abstract
A simple method for imaging biological tissue samples by electron microscopy and its correlation with super-resolution light microscopy is presented. This room temperature protocol, based on protecting thin biological specimens with methylcellulose and imaging with low voltage scanning electron microscopy, circumvents complex classical electron microscopy sample preparation steps requiring dehydration, resin embedding and use of contrast agents. This technique facilitates visualization of subcellular structures e.g. synaptic clefts and synaptic vesicles in mouse brain tissue and the organization of mitochondrial cristae in the zebrafish retina. Application of immunogold protocols to these samples can determine the precise localization of synaptic proteins and, in combination with super-resolution light microscopy methods clearly pinpoints the subcellular distribution of several proteins in the tissue. The simplicity of the method, including section collection on a silicon wafer, reduces artefacts and correlates protein location with sample morphology.
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74
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Chang R, Eriksen J, Edwards RH. The dual role of chloride in synaptic vesicle glutamate transport. eLife 2018; 7:e34896. [PMID: 30040066 PMCID: PMC6057745 DOI: 10.7554/elife.34896] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Accepted: 06/07/2018] [Indexed: 01/23/2023] Open
Abstract
The transport of glutamate into synaptic vesicles exhibits an unusual form of regulation by Cl- as well as an associated Cl- conductance. To distinguish direct effects of Cl- on the transporter from indirect effects via the driving force Δψ, we used whole endosome recording and report the first currents due to glutamate flux by the vesicular glutamate transporters (VGLUTs). Chloride allosterically activates the VGLUTs from both sides of the membrane, and we find that neutralization of an arginine in transmembrane domain four suffices for the lumenal activation. The dose dependence suggests that Cl- permeates through a channel and glutamate through a transporter. Competition between the anions nonetheless indicates that they use a similar permeation pathway. By controlling both ionic gradients and Δψ, endosome recording isolates different steps in the process of synaptic vesicle filling, suggesting distinct roles for Cl- in both allosteric activation and permeation.
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Affiliation(s)
- Roger Chang
- Department of PhysiologyUCSF School of MedicineSan FranciscoUnited States
- Department of NeurologyUCSF School of MedicineSan FranciscoUnited States
- Graduate Program in Biomedical SciencesUCSF School of MedicineSan FranciscoUnited States
| | - Jacob Eriksen
- Department of PhysiologyUCSF School of MedicineSan FranciscoUnited States
- Department of NeurologyUCSF School of MedicineSan FranciscoUnited States
| | - Robert H Edwards
- Department of PhysiologyUCSF School of MedicineSan FranciscoUnited States
- Department of NeurologyUCSF School of MedicineSan FranciscoUnited States
- Graduate Program in Biomedical SciencesUCSF School of MedicineSan FranciscoUnited States
- Kavli Institute for Fundamental NeuroscienceUCSF School of MedicineSan FranciscoUnited States
- Weill Institute for NeurosciencesUCSF School of MedicineSan FranciscoUnited States
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75
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Liu Y, Li C, Jia X, Huang L, Weiss JW. AMPA Receptor-Dependent Glutamatergic Signaling is Present in the Carotid Chemoreceptor. Neuroscience 2018; 382:59-68. [PMID: 29723577 DOI: 10.1016/j.neuroscience.2018.04.032] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Revised: 04/18/2018] [Accepted: 04/20/2018] [Indexed: 12/24/2022]
Abstract
Exposure to both sustained and intermittent hypoxia for as little as a day produces sustained augmentation of carotid chemoreceptor sensitivity; however, the molecular basis for this chemoreflex plasticity remains uncertain. We previously reported that NMDA receptor-dependent glutamatergic signaling in rat carotid body played a role in altered hypoxic sensitivity after exposure to cyclic intermittent hypoxia (CIH). Here we found that mRNAs of multiple AMPA and Kainate glutamate receptors were expressed in rat carotid body. The AMPA receptor subunit GluR1 showed intense immunoreactivity in the carotid body, co-localizing with tyrosine hydroxylase in type I cells. Treatment of rat carotid body-derived primary cells with AMPA activated ERK1/2 in a time-dependent manner. Exposing Sprague-Dawley rats to CIH for 8 h/day for 3 weeks significantly enhanced the expression level of GluA1 mRNA as well as GluR1 protein in the carotid body. In addition, our results showed that multiple of vesicular glutamate transporters (VGLUTs) and excitatory amino acid transporters (EAATs) were expressed in the rat carotid body, indicating that glutamate might be as a neurotransmitter stored, released and uptake in the carotid body. Finally, we found that mRNAs of GluA1, GluA2 and GluA3 as well as PSD-95-like membrane-associated granulate kinase family members, PSD-95, PSD-93, and SAP97, were expressed in human carotid body. Our data suggest AMPA receptor-dependent glutamatergic signaling is present in the carotid body and might be involved in the carotid chemoreceptor response to hypoxia.
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Affiliation(s)
- Yuzhen Liu
- The First Affiliated Hospital of Xinxiang Medical University, Henan Key Laboratory of Neural Regeneration, Weihui, Henan 453100, China; Division of Pulmonary, Critical Care and Sleep Medicine, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA.
| | - Chaohong Li
- The First Affiliated Hospital of Xinxiang Medical University, Henan Key Laboratory of Neural Regeneration, Weihui, Henan 453100, China
| | - Xianglei Jia
- The First Affiliated Hospital of Xinxiang Medical University, Henan Key Laboratory of Neural Regeneration, Weihui, Henan 453100, China
| | - Lu Huang
- The First Affiliated Hospital of Xinxiang Medical University, Henan Key Laboratory of Neural Regeneration, Weihui, Henan 453100, China
| | - J Woodrow Weiss
- Division of Pulmonary, Critical Care and Sleep Medicine, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA
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76
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Hayashi MK. Structure-Function Relationship of Transporters in the Glutamate-Glutamine Cycle of the Central Nervous System. Int J Mol Sci 2018; 19:ijms19041177. [PMID: 29649168 PMCID: PMC5979278 DOI: 10.3390/ijms19041177] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 04/09/2018] [Accepted: 04/10/2018] [Indexed: 12/12/2022] Open
Abstract
Many kinds of transporters contribute to glutamatergic excitatory synaptic transmission. Glutamate is loaded into synaptic vesicles by vesicular glutamate transporters to be released from presynaptic terminals. After synaptic vesicle release, glutamate is taken up by neurons or astrocytes to terminate the signal and to prepare for the next signal. Glutamate transporters on the plasma membrane are responsible for transporting glutamate from extracellular fluid to cytoplasm. Glutamate taken up by astrocyte is converted to glutamine by glutamine synthetase and transported back to neurons through glutamine transporters on the plasma membranes of the astrocytes and then on neurons. Glutamine is converted back to glutamate by glutaminase in the neuronal cytoplasm and then loaded into synaptic vesicles again. Here, the structures of glutamate transporters and glutamine transporters, their conformational changes, and how they use electrochemical gradients of various ions for substrate transport are summarized. Pharmacological regulations of these transporters are also discussed.
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Affiliation(s)
- Mariko Kato Hayashi
- School of Medicine, International University of Health and Welfare, 4-3 Kozunomori, Narita, Chiba 286-8686, Japan.
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77
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Preobraschenski J, Cheret C, Ganzella M, Zander JF, Richter K, Schenck S, Jahn R, Ahnert-Hilger G. Dual and Direction-Selective Mechanisms of Phosphate Transport by the Vesicular Glutamate Transporter. Cell Rep 2018; 23:535-545. [DOI: 10.1016/j.celrep.2018.03.055] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Revised: 02/13/2018] [Accepted: 03/14/2018] [Indexed: 11/30/2022] Open
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Horváth HR, Fazekas CL, Balázsfi D, Jain SK, Haller J, Zelena D. Contribution of Vesicular Glutamate Transporters to Stress Response and Related Psychopathologies: Studies in VGluT3 Knockout Mice. Cell Mol Neurobiol 2018; 38:37-52. [PMID: 28776199 PMCID: PMC11482036 DOI: 10.1007/s10571-017-0528-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Accepted: 07/28/2017] [Indexed: 10/19/2022]
Abstract
Maintenance of the homeostasis in a constantly changing environment is a fundamental process of life. Disturbances of the homeostatic balance is defined as stress response and is induced by wide variety of challenges called stressors. Being the main excitatory neurotransmitter of the central nervous system glutamate is important in the adaptation process of stress regulating both the catecholaminergic system and the hypothalamic-pituitary-adrenocortical axis. Data are accumulating about the role of different glutamatergic receptors at all levels of these axes, but little is known about the contribution of different vesicular glutamate transporters (VGluT1-3) characterizing the glutamatergic neurons. Here we summarize basic knowledge about VGluTs, their role in physiological regulation of stress adaptation, as well as their contribution to stress-related psychopathology. Most of our knowledge comes from the VGluT3 knockout mice, as VGluT1 and 2 knockouts are not viable. VGluT3 was discovered later than, and is not as widespread as the VGluT1 and 2. It may co-localize with other transmitters, and participate in retrograde signaling; as such its role might be unique. Previous reports using VGluT3 knockout mice showed enhanced anxiety and innate fear compared to wild type. Moreover, these knockout animals had enhanced resting corticotropin-releasing hormone mRNA levels in the hypothalamus and disturbed glucocorticoid stress responses. In conclusion, VGluT3 participates in stress adaptation regulation. The neuroendocrine changes observed in VGluT3 knockout mice may contribute to their anxious, fearful phenotype.
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Affiliation(s)
- Hanga Réka Horváth
- Institute of Experimental Medicine, Hungarian Academy of Sciences, 43, Szigony utca, Szigony 43, 1083, Budapest, Hungary
| | - Csilla Lea Fazekas
- Institute of Experimental Medicine, Hungarian Academy of Sciences, 43, Szigony utca, Szigony 43, 1083, Budapest, Hungary
| | - Diána Balázsfi
- Institute of Experimental Medicine, Hungarian Academy of Sciences, 43, Szigony utca, Szigony 43, 1083, Budapest, Hungary
- János Szentágothai School of Neurosciences, Semmelweis University, 26, Üllői út, 1085, Budapest, Hungary
| | | | - József Haller
- Institute of Experimental Medicine, Hungarian Academy of Sciences, 43, Szigony utca, Szigony 43, 1083, Budapest, Hungary
| | - Dóra Zelena
- Institute of Experimental Medicine, Hungarian Academy of Sciences, 43, Szigony utca, Szigony 43, 1083, Budapest, Hungary.
- Centre for Neuroscience, Szentágothai Research Centre, Institute of Physiology, Medical School, University of Pécs, Pécs, Hungary.
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79
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Yu W, Shi X, Cui X, Niu Y, Zhang W, Bai X, Wang Q, Hu L, Wang S. Jian-Pi-Zhi-Dong-Decoction regulates the expression of glutamate transporters to attenuate glutamate excitotoxicity and exerts anti-tics effects in Tourette syndrome model rats. Neuropsychiatr Dis Treat 2018; 14:3381-3392. [PMID: 30587990 PMCID: PMC6301307 DOI: 10.2147/ndt.s185169] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
PURPOSE This study explored whether Jian-Pi-Zhi-Dong-Decoction (JPZDD) could regulate the metabolism of glutamate (GLU) and its transporters in the striatum to exert anti-tics effects in Tourette syndrome (TS) rats. MATERIALS AND METHODS We randomly assigned 56 Sprague Dawley rats into four groups, each with 14 rats: control, model, tiapride (Tia), and JPZDD. TS groups (model, Tia, and JPZDD) received intraperitoneal injection of 3,3'-iminodipropionitrile for 7 days to establish TS model. Thereafter, rats in the four groups were treated differently once a day for 6 weeks. Behavioral evaluation was performed each week by using stereotypy recording and autonomic activity test. The level of GLU in the striatum was examined by high-performance liquid chromatography. Expression of EAAT1 and VGLUT1 were measured by quantitative real-time PCR (qRT-PCR) and laser scanning confocal microscope. RESULTS Compared with the model group, the stereotypy score and autonomic activity were decreased in Tia and JPZDD groups. Notably, the model group had increased concentration of GLU, which decreased after JPZDD and Tia treatments. In the model group, EAAT1 and glial cells were highly co-expressed and the relative fluorescence intensity (FI) of EAAT1 was significantly lower than that in the control group. Treatment with JPZDD and Tia increased the relative FI of EAAT1. The mRNA level of EAAT1 decreased in the model group compared to that in the control group, although it was significantly elevated following JPZDD or Tia treatment. In the model group, there was low co-expression of VGLUT1 and axon cells and the FI of VGLUT1 was remarkably increased relative to that in the control group and reduced following treatment with JPZDD and Tia. A similar trend was observed in the mRNA and protein expression of VGLUT1, although it was not statistically significant. CONCLUSION The mechanism by which JPZDD alleviated behavioral dysfunction of TS rats may be associated with maintaining normal GLU transport by upregulating EAAT1 and down-regulating VGLUT1 in the striatum.
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Affiliation(s)
- Wenjing Yu
- Department of Pediatrics, Beijing University of Chinese Medicine Third Affiliated Hospital, Beijing University of Chinese Medicine, Beijing, China
| | - Xiaowei Shi
- School of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing, China
| | - Xia Cui
- Department of Pediatrics, Beijing University of Chinese Medicine Third Affiliated Hospital, Beijing University of Chinese Medicine, Beijing, China
| | - Yan Niu
- Department of Pediatrics, Beijing University of Chinese Medicine Third Affiliated Hospital, Beijing University of Chinese Medicine, Beijing, China
| | - Wen Zhang
- Department of Pediatrics, Beijing University of Chinese Medicine Third Affiliated Hospital, Beijing University of Chinese Medicine, Beijing, China
| | - Xue Bai
- Department of Pediatrics, First Affiliated Hospital, Heilongjiang University of Chinese Medicine, Harbin, China
| | - Qian Wang
- Department of Pediatrics, Beijing University of Chinese Medicine Third Affiliated Hospital, Beijing University of Chinese Medicine, Beijing, China
| | - Lijun Hu
- Department of Pediatrics, Beijing University of Chinese Medicine Third Affiliated Hospital, Beijing University of Chinese Medicine, Beijing, China
| | - Sumei Wang
- Department of Pediatrics, Dongfang Hospital, Beijing University of Chinese Medicine, Beijing, China,
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Martineau M, Guzman RE, Fahlke C, Klingauf J. VGLUT1 functions as a glutamate/proton exchanger with chloride channel activity in hippocampal glutamatergic synapses. Nat Commun 2017; 8:2279. [PMID: 29273736 PMCID: PMC5741633 DOI: 10.1038/s41467-017-02367-6] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Accepted: 11/24/2017] [Indexed: 12/18/2022] Open
Abstract
Glutamate is the major excitatory transmitter in the vertebrate nervous system. To maintain synaptic efficacy, recycling synaptic vesicles (SV) are refilled with glutamate by vesicular glutamate transporters (VGLUTs). The dynamics and mechanism of glutamate uptake in intact neurons are still largely unknown. Here, we show by live-cell imaging with pH- and chloride-sensitive fluorescent probes in cultured hippocampal neurons of wild-type and VGLUT1-deficient mice that in SVs VGLUT functions as a glutamate/proton exchanger associated with a channel-like chloride conductance. After endocytosis most internalized Cl− is substituted by glutamate in an electrically, and presumably osmotically, neutral manner, and this process is driven by both the Cl− gradient itself and the proton motive force provided by the vacuolar H+-ATPase. Our results shed light on the transport mechanism of VGLUT under physiological conditions and provide a framework for how modulation of glutamate transport via Cl− and pH can change synaptic strength. During neurotransmission synaptic vesicles are filled with glutamate by vesicular glutamate transporters (VGLUTs). Here, authors image intact neurons and show that in synaptic vesicles VGLUT functions as a glutamate/proton exchanger associated with a channel-like chloride conductance.
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Affiliation(s)
- Magalie Martineau
- Department of Cellular Biophysics, Institute for Medical Physics and Biophysics, University of Muenster, 48149, Muenster, Germany. .,University of Bordeaux and Centre National de la Recherche Scientifique, Interdisciplinary Institute for Neuroscience, UMR 5297, F-33000, Bordeaux, France.
| | - Raul E Guzman
- Institute of Complex Systems, Zelluläre Biophysik (ICS-4), Forschungszentrum Jülich, 52425, Jülich, Germany
| | - Christoph Fahlke
- Institute of Complex Systems, Zelluläre Biophysik (ICS-4), Forschungszentrum Jülich, 52425, Jülich, Germany
| | - Jürgen Klingauf
- Department of Cellular Biophysics, Institute for Medical Physics and Biophysics, University of Muenster, 48149, Muenster, Germany. .,IZKF Münster and Cluster of Excellence EXC 1003, Cells in Motion (CiM), 48149, Muenster, Germany.
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81
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Choudhary B, Kamak M, Ratnakaran N, Kumar J, Awasthi A, Li C, Nguyen K, Matsumoto K, Hisamoto N, Koushika SP. UNC-16/JIP3 regulates early events in synaptic vesicle protein trafficking via LRK-1/LRRK2 and AP complexes. PLoS Genet 2017; 13:e1007100. [PMID: 29145394 PMCID: PMC5716593 DOI: 10.1371/journal.pgen.1007100] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2017] [Revised: 12/05/2017] [Accepted: 11/02/2017] [Indexed: 01/02/2023] Open
Abstract
JIP3/UNC-16/dSYD is a MAPK-scaffolding protein with roles in protein trafficking. We show that it is present on the Golgi and is necessary for the polarized distribution of synaptic vesicle proteins (SVPs) and dendritic proteins in neurons. UNC-16 excludes Golgi enzymes from SVP transport carriers and facilitates inclusion of specific SVPs into the same transport carrier. The SVP trafficking roles of UNC-16 are mediated through LRK-1, whose localization to the Golgi is reduced in unc-16 animals. UNC-16, through LRK-1, also enables Golgi-localization of the μ-subunit of the AP-1 complex. AP1 regulates the size but not the composition of SVP transport carriers. Additionally, UNC-16 and LRK-1 through the AP-3 complex regulates the composition but not the size of the SVP transport carrier. These early biogenesis steps are essential for dependence on the synaptic vesicle motor, UNC-104 for axonal transport. Our results show that UNC-16 and its downstream effectors, LRK-1 and the AP complexes function at the Golgi and/or post-Golgi compartments to control early steps of SV biogenesis. The UNC-16 dependent steps of exclusion, inclusion and motor recruitment are critical for polarized distribution of neuronal cargo. Synaptic vesicles (SVs) have a defined composition and size at the synapse. The multiple synaptic vesicle proteins (SVPs) found on these vesicle membranes are synthesized at and trafficked out of the cell body in distinct transport carriers. However, we do not yet understand how different SVPs are sorted and trafficked to the synapse. We show that UNC-16/JIP3 plays a critical role, in a series of essential steps, to ensure proper membrane composition and size of the ensuing SVP carrier exiting the cell body. These processes are “exclusion” of resident Golgi enzymes followed by the “inclusion” of synaptic vesicle proteins in the same transport carrier. Regulation of composition and size seems to occur independently of each other and depends on two distinct AP complexes acting downstream to LRK-1. Our study further indicates that the composition of the transport carrier formed is important for the recruitment of motors and consequently for the polarized localization of SVPs.
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Affiliation(s)
- Bikash Choudhary
- National Centre for Biological Sciences-Tata Institute of Fundamental Research, Bangalore, Karnataka, India
| | - Madhushree Kamak
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, Maharashtra, India
| | - Neena Ratnakaran
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, Maharashtra, India
| | - Jitendra Kumar
- National Centre for Biological Sciences-Tata Institute of Fundamental Research, Bangalore, Karnataka, India
| | - Anjali Awasthi
- National Centre for Biological Sciences-Tata Institute of Fundamental Research, Bangalore, Karnataka, India
- Department of Biological Sciences, Birla Institute of Technology and Science, Pilani, Rajasthan, India
| | - Chun Li
- Group of Signaling Mechanisms, Nagoya University, Nagoya, Japan
| | - Ken Nguyen
- Center for C. elegans Anatomy, Albert Einstein College of Medicine, New York, New York, United States of America
| | | | - Naoki Hisamoto
- Group of Signaling Mechanisms, Nagoya University, Nagoya, Japan
| | - Sandhya P. Koushika
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, Maharashtra, India
- * E-mail:
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Sasakura Y, Hozumi A. Formation of adult organs through metamorphosis in ascidians. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2017; 7. [PMID: 29105358 DOI: 10.1002/wdev.304] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 08/28/2017] [Accepted: 09/11/2017] [Indexed: 02/05/2023]
Abstract
The representative characteristic of ascidians is their vertebrate-like, tadpole shape at the larval stage. Ascidians lose the tadpole shape through metamorphosis to become adults with a nonmotile, sessile body and a shape generally considered distinct from that of vertebrates. Solitary ascidians including Ciona species are extensively studied to understand the developmental mechanisms of ascidians, and to compare these mechanisms with their counterparts in vertebrates. In these ascidian species, the digestive and circulatory systems are not well developed in the larval trunk and the larvae do not take food. This is in contrast with the inner conditions of vertebrate tadpoles, which have functional organs comparable to those of adults. The adult organs and tissues of these ascidians become functional during metamorphosis that is completed quickly, suggesting that the ascidian larvae of solitary species are a transient stage of development. We here discuss how the cells and tissues in the ascidian larval body are converted into those of adults. The hearts of ascidians and vertebrates use closely related cellular and molecular mechanisms that suggest their shared origin. Hox genes of ascidians are essential for forming adult endodermal structures. To fully understand the development and evolution of chordates, a complete elucidation of the mechanisms underlying the adult tissue/organ formation of ascidians will be needed. WIREs Dev Biol 2018, 7:e304. doi: 10.1002/wdev.304 This article is categorized under: Comparative Development and Evolution > Body Plan Evolution Early Embryonic Development > Development to the Basic Body Plan.
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Affiliation(s)
- Yasunori Sasakura
- Shimoda Marine Research Center, University of Tsukuba, Shimoda, Shizuoka, Japan
| | - Akiko Hozumi
- Shimoda Marine Research Center, University of Tsukuba, Shimoda, Shizuoka, Japan
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83
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Júnior GAO, Perez BC, Cole JB, Santana MHA, Silveira J, Mazzoni G, Ventura RV, Júnior MLS, Kadarmideen HN, Garrick DJ, Ferraz JBS. Genomic study and Medical Subject Headings enrichment analysis of early pregnancy rate and antral follicle numbers in Nelore heifers. J Anim Sci 2017; 95:4796-4812. [PMID: 29293733 PMCID: PMC6292327 DOI: 10.2527/jas2017.1752] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 08/24/2017] [Indexed: 12/18/2022] Open
Abstract
Zebu animals () are known to take longer to reach puberty compared with taurine animals (), limiting the supply of animals for harvest or breeding and impacting profitability. Genomic information can be a helpful tool to better understand complex traits and improve genetic gains. In this study, we performed a genomewide association study (GWAS) to identify genetic variants associated with reproductive traits in Nelore beef cattle. Heifer pregnancy (HP) was recorded for 1,267 genotyped animals distributed in 12 contemporary groups (CG) with an average pregnancy rate of 0.35 (±0.01). Disregarding one of these CG, the number of antral follicles (NF) was also collected for 937 of these animals, with an average of 11.53 (±4.43). The animals were organized in CG: 12 and 11 for HP and NF, respectively. Genes in linkage disequilibrium (LD) with the associated variants can be considered in a functional enrichment analysis to identify biological mechanisms involved in fertility. Medical Subject Headings (MeSH) were detected using the MESHR package, allowing the extraction of broad meanings from the gene lists provided by the GWAS. The estimated heritability for HP was 0.28 ± 0.07 and for NF was 0.49 ± 0.09, with the genomic correlation being -0.21 ± 0.29. The average LD between adjacent markers was 0.23 ± 0.01, and GWAS identified genomic windows that accounted for >1% of total genetic variance on chromosomes 5, 14, and 18 for HP and on chromosomes 2, 8, 11, 14, 15, 16, and 22 for NF. The MeSH enrichment analyses revealed significant ( < 0.05) terms associated with HP-"Munc18 Proteins," "Fucose," and "Hemoglobins"-and with NF-"Cathepsin B," "Receptors, Neuropeptide," and "Palmitic Acid." This is the first study in Nelore cattle introducing the concept of MeSH analysis. The genomic analyses contributed to a better understanding of the genetic control of the reproductive traits HP and NF and provide new selection strategies to improve beef production.
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Affiliation(s)
| | - B. C. Perez
- Universidade de São Paulo (USP), Pirassununga, SP, Brazil
| | - J. B. Cole
- Animal Genomics and Improvement Laboratory, Agricultural Research Service, USDA, Beltsville, MD 20705-2350
| | | | - J. Silveira
- Universidade de São Paulo (USP), Pirassununga, SP, Brazil
| | - G. Mazzoni
- Department of Veterinary and Animal Sciences, University of Copenhagen, Denmark
- Section of Systems Genomics, Department of Bio and Health Informatics, Technical University of Denmark, Kemitorvet, 2800 Kgs. Lyngby, Denmark
| | - R. V. Ventura
- Beef Improvement Opportunities, Guelph, ON N1K1E5, Canada
- Centre for Genetic Improvement of Livestock, University of Guelph, Guelph, ON N1G2W1, Canada
| | | | - H. N. Kadarmideen
- Section of Systems Genomics, Department of Bio and Health Informatics, Technical University of Denmark, Kemitorvet, 2800 Kgs. Lyngby, Denmark
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Murao N, Yokoi N, Honda K, Han G, Hayami T, Gheni G, Takahashi H, Minami K, Seino S. Essential roles of aspartate aminotransferase 1 and vesicular glutamate transporters in β-cell glutamate signaling for incretin-induced insulin secretion. PLoS One 2017; 12:e0187213. [PMID: 29091932 PMCID: PMC5665537 DOI: 10.1371/journal.pone.0187213] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Accepted: 10/16/2017] [Indexed: 01/18/2023] Open
Abstract
Incretins (GLP-1 and GIP) potentiate insulin secretion through cAMP signaling in pancreatic β-cells in a glucose-dependent manner. We recently proposed a mechanistic model of incretin-induced insulin secretion (IIIS) that requires two critical processes: 1) generation of cytosolic glutamate through the malate-aspartate (MA) shuttle in glucose metabolism and 2) glutamate transport into insulin granules by cAMP signaling to promote insulin granule exocytosis. To directly prove the model, we have established and characterized CRISPR/Cas9-engineered clonal mouse β-cell lines deficient for the genes critical in these two processes: aspartate aminotransferase 1 (AST1, gene symbol Got1), a key enzyme in the MA shuttle, which generates cytosolic glutamate, and the vesicular glutamate transporters (VGLUT1, VGLUT2, and VGLUT3, gene symbol Slc17a7, Slc17a6, and Slc17a8, respectively), which participate in glutamate transport into secretory vesicles. Got1 knockout (KO) β-cell lines were defective in cytosolic glutamate production from glucose and showed impaired IIIS. Unexpectedly, different from the previous finding that global Slc17a7 KO mice exhibited impaired IIIS from pancreatic islets, β-cell specific Slc17a7 KO mice showed no significant impairment in IIIS, as assessed by pancreas perfusion experiment. Single Slc17a7 KO β-cell lines also retained IIIS, probably due to compensatory upregulation of Slc17a6. Interestingly, triple KO of Slc17a7, Slc17a6, and Slc17a8 diminished IIIS, which was rescued by exogenously introduced wild-type Slc17a7 or Slc17a6 genes. The present study provides direct evidence for the essential roles of AST1 and VGLUTs in β-cell glutamate signaling for IIIS and also shows the usefulness of the CRISPR/Cas9 system for studying β-cells by simultaneous disruption of multiple genes.
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Affiliation(s)
- Naoya Murao
- Division of Molecular and Metabolic Medicine, Department of Physiology and Cell Biology, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Norihide Yokoi
- Division of Molecular and Metabolic Medicine, Department of Physiology and Cell Biology, Kobe University Graduate School of Medicine, Kobe, Japan
- * E-mail: (NY); (SS)
| | - Kohei Honda
- Division of Molecular and Metabolic Medicine, Department of Physiology and Cell Biology, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Guirong Han
- Division of Molecular and Metabolic Medicine, Department of Physiology and Cell Biology, Kobe University Graduate School of Medicine, Kobe, Japan
- Kansai Electric Power Medical Research Institute, Kobe, Japan
- Division of Medical Chemistry, Department of Biophysics, Kobe University Graduate School of Health Sciences, Kobe, Japan
| | - Tomohide Hayami
- Division of Molecular and Metabolic Medicine, Department of Physiology and Cell Biology, Kobe University Graduate School of Medicine, Kobe, Japan
- Kansai Electric Power Medical Research Institute, Kobe, Japan
- Division of Diabetes, Department of Internal Medicine, Aichi Medical University, Nagakute, Japan
| | - Ghupurjan Gheni
- Division of Molecular and Metabolic Medicine, Department of Physiology and Cell Biology, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Harumi Takahashi
- Division of Molecular and Metabolic Medicine, Department of Physiology and Cell Biology, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Kohtaro Minami
- Division of Molecular and Metabolic Medicine, Department of Physiology and Cell Biology, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Susumu Seino
- Division of Molecular and Metabolic Medicine, Department of Physiology and Cell Biology, Kobe University Graduate School of Medicine, Kobe, Japan
- * E-mail: (NY); (SS)
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Li H, Santos MS, Park CK, Dobry Y, Voglmaier SM. VGLUT2 Trafficking Is Differentially Regulated by Adaptor Proteins AP-1 and AP-3. Front Cell Neurosci 2017; 11:324. [PMID: 29123471 PMCID: PMC5662623 DOI: 10.3389/fncel.2017.00324] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2017] [Accepted: 09/28/2017] [Indexed: 01/25/2023] Open
Abstract
Release of the major excitatory neurotransmitter glutamate by synaptic vesicle exocytosis depends on glutamate loading into synaptic vesicles by vesicular glutamate transporters (VGLUTs). The two principal isoforms, VGLUT1 and 2, exhibit a complementary pattern of expression in adult brain that broadly distinguishes cortical (VGLUT1) and subcortical (VGLUT2) systems, and correlates with distinct physiological properties in synapses expressing these isoforms. Differential trafficking of VGLUT1 and 2 has been suggested to underlie their functional diversity. Increasing evidence suggests individual synaptic vesicle proteins use specific sorting signals to engage specialized biochemical mechanisms to regulate their recycling. We observed that VGLUT2 recycles differently in response to high frequency stimulation than VGLUT1. Here we further explore the trafficking of VGLUT2 using a pHluorin-based reporter, VGLUT2-pH. VGLUT2-pH exhibits slower rates of both exocytosis and endocytosis than VGLUT1-pH. VGLUT2-pH recycling is slower than VGLUT1-pH in both hippocampal neurons, which endogenously express mostly VGLUT1, and thalamic neurons, which endogenously express mostly VGLUT2, indicating that protein identity, not synaptic vesicle membrane or neuronal cell type, controls sorting. We characterize sorting signals in the C-terminal dileucine-like motif, which plays a crucial role in VGLUT2 trafficking. Disruption of this motif abolishes synaptic targeting of VGLUT2 and essentially eliminates endocytosis of the transporter. Mutational and biochemical analysis demonstrates that clathrin adaptor proteins (APs) interact with VGLUT2 at the dileucine-like motif. VGLUT2 interacts with AP-2, a well-studied adaptor protein for clathrin mediated endocytosis. In addition, VGLUT2 also interacts with the alternate adaptors, AP-1 and AP-3. VGLUT2 relies on distinct recycling mechanisms from VGLUT1. Abrogation of these differences by pharmacological and molecular inhibition reveals that these mechanisms are dependent on the adaptor proteins AP-1 and AP-3. Further, shRNA-mediated knockdown reveals differential roles for AP-1 and AP-3 in VGLUT2 recycling.
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Affiliation(s)
- Haiyan Li
- Department of Psychiatry, School of Medicine, Weill Institute for Neurosciences, Kavli Institute for Fundamental Neuroscience, University of California, San Francisco, San Francisco, CA, United States
| | - Magda S Santos
- Department of Psychiatry, School of Medicine, Weill Institute for Neurosciences, Kavli Institute for Fundamental Neuroscience, University of California, San Francisco, San Francisco, CA, United States
| | - Chihyung K Park
- Department of Psychiatry, School of Medicine, Weill Institute for Neurosciences, Kavli Institute for Fundamental Neuroscience, University of California, San Francisco, San Francisco, CA, United States
| | - Yuriy Dobry
- Department of Psychiatry, School of Medicine, Weill Institute for Neurosciences, Kavli Institute for Fundamental Neuroscience, University of California, San Francisco, San Francisco, CA, United States
| | - Susan M Voglmaier
- Department of Psychiatry, School of Medicine, Weill Institute for Neurosciences, Kavli Institute for Fundamental Neuroscience, University of California, San Francisco, San Francisco, CA, United States
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El-Ansary A, Bjørklund G, Chirumbolo S, Alnakhli OM. Predictive value of selected biomarkers related to metabolism and oxidative stress in children with autism spectrum disorder. Metab Brain Dis 2017; 32:1209-1221. [PMID: 28497358 DOI: 10.1007/s11011-017-0029-x] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/26/2016] [Accepted: 05/01/2017] [Indexed: 10/19/2022]
Abstract
Autism spectrum disorder (ASD) as a neurodevelopmental disorder is characterized by impairments in social interaction, communication, and restricted, repetitive behavior. Several and reproducible studies have suggested that oxidative stress may represent one of the primary etiological mechanism of ASD that can be targeted for therapeutic intervention. In the present study, multiple regression and combined receiver operating characteristic (ROC) analysis were used to search for a relationship between impaired energy and oxidative metabolic pathways in the etiology of ASD and to find the linear combination that maximizes the partial area under a ROC curve for a pre-identified set of markers related to energy metabolism and oxidative stress. Thirty children with ASD and 30 age and gender matched controls were enrolled in the study. Using either spectrophotometric or ELISA-colorimetric assay, levels of lipid peroxides, vitamin E, vitamin C, glutathione (GSH)/glutathione disulfide (GSSG) together with the enzymatic activity of catalase, plasma glutathione peroxidase (GPx), and blood superoxide dismutase (SOD), were measured in peripheral blood samples, as biomarkers related to oxidative stress. Creatine kinase, ectonucleotidases (ADPase and ATPase) Na+/K+ (ATPase), lactate, inorganic phosphate, and levels of adenosine monophosphate (AMP), adenosine diphosphate (ADP), and adenosine triphosphate (ATP) together with adenylate energy charge, were also measured as markers of impaired energy metabolism. Statistical analysis using ROC curves, multiple and logistic regression were performed. A remarkable increase in the area under the curve for most of the combined markers, representing both energy impaired metabolism or oxidative stress, was observed by using combined ROC analyses. Moreover, higher specificity and sensitivity of the combined markers were also reported. The present study indicated that the measurement of the predictive value of selected biomarkers related to energy metabolism and oxidative stress in children with ASD using ROC analysis should lead to the better identification of the etiological mechanism of ASD associated with metabolism and diet. Agents with activity against the impaired metabolic pathway associated with ASD including the metabolic defects and involved enzymes hold a promise as a novel therapy for ASD.
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Affiliation(s)
- Afaf El-Ansary
- Central Laboratory, Female Center for Medical Studies and Scientific Section, King Saud University, Riyadh, Saudi Arabia.
| | - Geir Bjørklund
- Council for Nutritional and Environmental Medicine, Mo i Rana, Norway
| | - Salvatore Chirumbolo
- Department of Neurological and Movement Sciences, University of Verona, Verona, Italy
| | - Osima M Alnakhli
- Central Laboratory, Female Center for Medical Studies and Scientific Section, King Saud University, Riyadh, Saudi Arabia
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88
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Schenck S, Kunz L, Sahlender D, Pardon E, Geertsma ER, Savtchouk I, Suzuki T, Neldner Y, Štefanić S, Steyaert J, Volterra A, Dutzler R. Generation and Characterization of Anti-VGLUT Nanobodies Acting as Inhibitors of Transport. Biochemistry 2017; 56:3962-3971. [DOI: 10.1021/acs.biochem.7b00436] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Stephan Schenck
- Department
of Biochemistry, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Laura Kunz
- Department
of Biochemistry, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Daniela Sahlender
- Department
of Fundamental Neurosciences, University of Lausanne, Rue du Bugnon 9, 1005 Lausanne, Switzerland
| | - Els Pardon
- VIB
Center for Structural Biology, VIB, 1050 Brussels, Belgium
- Structural
Biology Brussels, Vrije Universiteit Brussel, 1050 Brussels, Belgium
| | - Eric R. Geertsma
- Department
of Biochemistry, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
- Institute
of Biochemistry, Biocenter, Goethe-University Frankfurt, Max-von-Laue-Straβe
9, 60438 Frankfurt
am Main, Germany
| | - Iaroslav Savtchouk
- Department
of Fundamental Neurosciences, University of Lausanne, Rue du Bugnon 9, 1005 Lausanne, Switzerland
| | - Toshiharu Suzuki
- Department
of Applied Chemistry, School of Engineering, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Yvonne Neldner
- Department
of Biochemistry, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Saša Štefanić
- Institute
of Parasitology, University of Zurich, Winterthurerstrasse 266a, 8057 Zurich, Switzerland
| | - Jan Steyaert
- VIB
Center for Structural Biology, VIB, 1050 Brussels, Belgium
- Structural
Biology Brussels, Vrije Universiteit Brussel, 1050 Brussels, Belgium
| | - Andrea Volterra
- Department
of Fundamental Neurosciences, University of Lausanne, Rue du Bugnon 9, 1005 Lausanne, Switzerland
| | - Raimund Dutzler
- Department
of Biochemistry, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
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89
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Distinct Fos-Expressing Neuronal Ensembles in the Ventromedial Prefrontal Cortex Mediate Food Reward and Extinction Memories. J Neurosci 2017; 36:6691-703. [PMID: 27335401 DOI: 10.1523/jneurosci.0140-16.2016] [Citation(s) in RCA: 95] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Accepted: 05/09/2016] [Indexed: 11/21/2022] Open
Abstract
UNLABELLED In operant learning, initial reward-associated memories are thought to be distinct from subsequent extinction-associated memories. Memories formed during operant learning are thought to be stored in "neuronal ensembles." Thus, we hypothesize that different neuronal ensembles encode reward- and extinction-associated memories. Here, we examined prefrontal cortex neuronal ensembles involved in the recall of reward and extinction memories of food self-administration. We first trained rats to lever press for palatable food pellets for 7 d (1 h/d) and then exposed them to 0, 2, or 7 daily extinction sessions in which lever presses were not reinforced. Twenty-four hours after the last training or extinction session, we exposed the rats to either a short 15 min extinction test session or left them in their homecage (a control condition). We found maximal Fos (a neuronal activity marker) immunoreactivity in the ventral medial prefrontal cortex of rats that previously received 2 extinction sessions, suggesting that neuronal ensembles in this area encode extinction memories. We then used the Daun02 inactivation procedure to selectively disrupt ventral medial prefrontal cortex neuronal ensembles that were activated during the 15 min extinction session following 0 (no extinction) or 2 prior extinction sessions to determine the effects of inactivating the putative food reward and extinction ensembles, respectively, on subsequent nonreinforced food seeking 2 d later. Inactivation of the food reward ensembles decreased food seeking, whereas inactivation of the extinction ensembles increased food seeking. Our results indicate that distinct neuronal ensembles encoding operant reward and extinction memories intermingle within the same cortical area. SIGNIFICANCE STATEMENT A current popular hypothesis is that neuronal ensembles in different prefrontal cortex areas control reward-associated versus extinction-associated memories: the dorsal medial prefrontal cortex (mPFC) promotes reward seeking, whereas the ventral mPFC inhibits reward seeking. In this paper, we use the Daun02 chemogenetic inactivation procedure to demonstrate that Fos-expressing neuronal ensembles mediating both food reward and extinction memories intermingle within the same ventral mPFC area.
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90
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Kljakic O, Janickova H, Prado VF, Prado MAM. Cholinergic/glutamatergic co-transmission in striatal cholinergic interneurons: new mechanisms regulating striatal computation. J Neurochem 2017; 142 Suppl 2:90-102. [PMID: 28421605 DOI: 10.1111/jnc.14003] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Revised: 02/28/2017] [Accepted: 03/01/2017] [Indexed: 01/22/2023]
Abstract
It is well established that neurons secrete neuropeptides and ATP with classical neurotransmitters; however, certain neuronal populations are also capable of releasing two classical neurotransmitters by a process named co-transmission. Although there has been progress in our understanding of the molecular mechanism underlying co-transmission, the individual regulation of neurotransmitter secretion and the functional significance of this neuronal 'bilingualism' is still unknown. Striatal cholinergic interneurons (CINs) have been shown to secrete glutamate (Glu) in addition to acetylcholine (ACh) and are recognized for their role in the regulation of striatal circuits and behavior. Our review highlights the recent research into identifying mechanisms that regulate the secretion and function of Glu and ACh released by CINs and the roles these neurons play in regulating dopamine secretion and striatal activity. In particular, we focus on how the transporters for ACh (VAChT) and Glu (VGLUT3) influence the storage of neurotransmitters in CINs. We further discuss how these individual neurotransmitters regulate striatal computation and distinct aspects of behavior that are regulated by the striatum. We suggest that understanding the distinct and complementary functional roles of these two neurotransmitters may prove beneficial in the development of therapies for Parkinson's disease and addiction. Overall, understanding how Glu and ACh secreted by CINs impacts striatal activity may provide insight into how different populations of 'bilingual' neurons are able to develop sophisticated regulation of their targets by interacting with multiple receptors but also by regulating each other's vesicular storage. This is an article for the special issue XVth International Symposium on Cholinergic Mechanisms.
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Affiliation(s)
- Ornela Kljakic
- Robarts Research Institute, Schulich School of Medicine & Dentistry, University of Western Ontario, London, Ontario, Canada.,Department of Anatomy and Cell Biology, Schulich School of Medicine & Dentistry, University of Western Ontario, London, Ontario, Canada
| | - Helena Janickova
- Robarts Research Institute, Schulich School of Medicine & Dentistry, University of Western Ontario, London, Ontario, Canada
| | - Vania F Prado
- Robarts Research Institute, Schulich School of Medicine & Dentistry, University of Western Ontario, London, Ontario, Canada.,Department of Anatomy and Cell Biology, Schulich School of Medicine & Dentistry, University of Western Ontario, London, Ontario, Canada.,Department of Physiology and Pharmacology, Schulich School of Medicine & Dentistry, University of Western Ontario, London, Ontario, Canada
| | - Marco A M Prado
- Robarts Research Institute, Schulich School of Medicine & Dentistry, University of Western Ontario, London, Ontario, Canada.,Department of Anatomy and Cell Biology, Schulich School of Medicine & Dentistry, University of Western Ontario, London, Ontario, Canada.,Department of Physiology and Pharmacology, Schulich School of Medicine & Dentistry, University of Western Ontario, London, Ontario, Canada
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91
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Farsi Z, Jahn R, Woehler A. Proton electrochemical gradient: Driving and regulating neurotransmitter uptake. Bioessays 2017; 39. [PMID: 28383767 DOI: 10.1002/bies.201600240] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Accumulation of neurotransmitters in the lumen of synaptic vesicles (SVs) relies on the activity of the vacuolar-type H+ -ATPase. This pump drives protons into the lumen, generating a proton electrochemical gradient (ΔμH+ ) across the membrane. Recent work has demonstrated that the balance between the chemical (ΔpH) and electrical (ΔΨ) components of ΔμH+ is regulated differently by some distinct vesicle types. As different neurotransmitter transporters use ΔpH and ΔΨ with different relative efficiencies, regulation of this gradient balance has the potential to influence neurotransmitter uptake. Nevertheless, the underlying mechanisms responsible for this regulation remain poorly understood. In this review, we provide an overview of current neurotransmitter uptake models, with a particular emphasis on the distinct roles of the electrical and chemical gradients and current hypotheses for regulatory mechanisms.
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Affiliation(s)
- Zohreh Farsi
- Max-Delbrück Center for Molecular Medicine, Berlin Institute for Medical Systems Biology, Berlin, Germany
| | - Reinhard Jahn
- Department of Neurobiology, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Andrew Woehler
- Max-Delbrück Center for Molecular Medicine, Berlin Institute for Medical Systems Biology, Berlin, Germany
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92
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Characterization of a Human Point Mutation of VGLUT3 (p.A211V) in the Rodent Brain Suggests a Nonuniform Distribution of the Transporter in Synaptic Vesicles. J Neurosci 2017; 37:4181-4199. [PMID: 28314816 DOI: 10.1523/jneurosci.0282-16.2017] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2016] [Revised: 02/21/2017] [Accepted: 02/23/2017] [Indexed: 11/21/2022] Open
Abstract
The atypical vesicular glutamate transporter type 3 (VGLUT3) is expressed by subpopulations of neurons using acetylcholine, GABA, or serotonin as neurotransmitters. In addition, VGLUT3 is expressed in the inner hair cells of the auditory system. A mutation (p.A211V) in the gene that encodes VGLUT3 is responsible for progressive deafness in two unrelated families. In this study, we investigated the consequences of the p.A211V mutation in cell cultures and in the CNS of a mutant mouse. The mutation substantially decreased VGLUT3 expression (-70%). We measured VGLUT3-p.A211V activity by vesicular uptake in BON cells, electrophysiological recording of isolated neurons, and its ability to stimulate serotonergic accumulation in cortical synaptic vesicles. Despite a marked loss of expression, the activity of the mutated isoform was only minimally altered. Furthermore, mutant mice displayed none of the behavioral alterations that have previously been reported in VGLUT3 knock-out mice. Finally, we used stimulated emission depletion microscopy to analyze how the mutation altered VGLUT3 distribution within the terminals of mice expressing the mutated isoform. The mutation appeared to reduce the expression of the VGLUT3 transporter by simultaneously decreasing the number of VGLUT3-positive synaptic vesicles and the amount of VGLUT3 per synapses. These observations suggested that VGLUT3 global activity is not linearly correlated with VGLUT3 expression. Furthermore, our data unraveled a nonuniform distribution of VGLUT3 in synaptic vesicles. Identifying the mechanisms responsible for this complex vesicular sorting will be critical to understand VGLUT's involvement in normal and pathological conditions.SIGNIFICANCE STATEMENT VGLUT3 is an atypical member of the vesicular glutamate transporter family. A point mutation of VGLUT3 (VGLUT3-p.A211V) responsible for a progressive loss of hearing has been identified in humans. We observed that this mutation dramatically reduces VGLUT3 expression in terminals (∼70%) without altering its function. Furthermore, using stimulated emission depletion microscopy, we found that reducing the expression levels of VGLUT3 diminished the number of VGLUT3-positive vesicles at synapses. These unexpected findings challenge the vision of a uniform distribution of synaptic vesicles at synapses. Therefore, the overall activity of VGLUT3 is not proportional to the level of VGLUT3 expression. These data will be key in interpreting the role of VGLUTs in human pathologies.
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93
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Crescenzi R, DeBrosse C, Nanga RP, Byrne MD, Krishnamoorthy G, D’Aquilla K, Nath H, Morales KH, Iba M, Hariharan H, Lee VM, Detre JA, Reddy R. Longitudinal imaging reveals subhippocampal dynamics in glutamate levels associated with histopathologic events in a mouse model of tauopathy and healthy mice. Hippocampus 2017; 27:285-302. [PMID: 27997993 PMCID: PMC5396955 DOI: 10.1002/hipo.22693] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Revised: 12/02/2016] [Accepted: 12/02/2016] [Indexed: 11/08/2022]
Abstract
Tauopathies are neurodegenerative disorders characterized by abnormal intracellular aggregates of tau protein, and include Alzheimer's disease, corticobasal degeneration, frontotemporal dementia, and traumatic brain injury. Glutamate metabolism is altered in neurodegenerative disorders manifesting in higher or lower concentrations of glutamate, its transporters or receptors. Previously, glutamate chemical exchange saturation transfer (GluCEST) magnetic resonance imaging (MRI) demonstrated that glutamate levels are reduced in regions of synapse loss in the hippocampus of a mouse model of late-stage tauopathy. We performed a longitudinal GluCEST imaging experiment paired with a cross-sectional study of histologic markers of tauopathy to determine whether (1) early GluCEST changes are associated with synapse loss before volume loss occurs in the hippocampus, and whether (2) subhippocampal dynamics in GluCEST are associated with histopathologic events related to glutamate alterations in tauopathy. Live imaging of the hippocampus in three serial slices was performed without exogenous contrast agents, and subregions were segmented based on a k-means cluster model. Subregions of the hippocampus were analyzed (cornu ammonis CA1, CA3, dentate gyrus DG, and ventricle) in order to associate local MRI-observable changes in glutamate with histological measures of glial cell proliferation (GFAP), synapse density (synaptophysin, VGlut1) and glutamate receptor (NMDA-NR1) levels. Early differences in GluCEST between healthy and tauopathy mice were measured in the CA1 and DG subregions (30% reduction, P ≤ 0.001). Synapse density was also significantly reduced in every subregion of the hippocampus in tauopathy mice by 6 months. Volume was not significantly reduced in any subregion until 13 months. Further, a gradient in glutamate levels was observed in vivo along hippocampal axes that became polarized as tauopathy progressed. Dynamics in hippocampal glutamate levels throughout lifetime were most closely correlated with combined changes in synaptophysin and GFAP, indicating that GluCEST imaging may be a surrogate marker of glutamate concentration in glial cells and at the synaptic level. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Rachelle Crescenzi
- Department of Biochemistry & Molecular Biophysics (BMB), University of Pennsylvania, Philadelphia, PA, USA
- Center for Magnetic Resonance and Optical Imaging (CMROI), University of Pennsylvania, Philadelphia, PA, USA
| | - Catherine DeBrosse
- Department of Biochemistry & Molecular Biophysics (BMB), University of Pennsylvania, Philadelphia, PA, USA
- Center for Magnetic Resonance and Optical Imaging (CMROI), University of Pennsylvania, Philadelphia, PA, USA
| | - Ravi P.R. Nanga
- Center for Magnetic Resonance and Optical Imaging (CMROI), University of Pennsylvania, Philadelphia, PA, USA
| | - Matthew D. Byrne
- Center for Neurodegenerative Disease Research (CNDR), University of Pennsylvania, Philadelphia, PA, USA
| | - Guruprasad Krishnamoorthy
- Center for Magnetic Resonance and Optical Imaging (CMROI), University of Pennsylvania, Philadelphia, PA, USA
| | - Kevin D’Aquilla
- Center for Magnetic Resonance and Optical Imaging (CMROI), University of Pennsylvania, Philadelphia, PA, USA
| | - Hari Nath
- Center for Magnetic Resonance and Optical Imaging (CMROI), University of Pennsylvania, Philadelphia, PA, USA
| | - Knashawn H. Morales
- Department of Biostatistics and Epidemiology, University of Pennsylvania, Philadelphia, PA, USA
| | - Michiyo Iba
- Center for Neurodegenerative Disease Research (CNDR), University of Pennsylvania, Philadelphia, PA, USA
| | - Hari Hariharan
- Center for Magnetic Resonance and Optical Imaging (CMROI), University of Pennsylvania, Philadelphia, PA, USA
| | - Virginia M.Y Lee
- Center for Neurodegenerative Disease Research (CNDR), University of Pennsylvania, Philadelphia, PA, USA
| | - John A. Detre
- Center for Functional Neuroimaging (CfN), University of Pennsylvania, Philadelphia, PA, USA
| | - Ravinder Reddy
- Center for Magnetic Resonance and Optical Imaging (CMROI), University of Pennsylvania, Philadelphia, PA, USA
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94
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Moriyama S, Iharada M, Omote H, Moriyama Y, Hiasa M. Function and expression of a splicing variant of vesicular glutamate transporter 1. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2017; 1859:931-940. [PMID: 28188742 DOI: 10.1016/j.bbamem.2017.02.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Revised: 01/30/2017] [Accepted: 02/05/2017] [Indexed: 10/20/2022]
Abstract
Vesicular glutamate transporter (VGLUT) is an active transporter responsible for vesicular storage of glutamate in synaptic vesicles and plays an essential role in glutamatergic neurotransmission. VGLUT consists of three isoforms, VGLUT1, VGLUT2, and VGLUT3. The VGLUT1 variant, VGLUT1v, with an additional 75-base pair sequence derived from a second intron between exons 2 and 3, which corresponds to 25 amino acid residues in the 1st loop of VGLUT1, is the only splicing variant among VGLUTs, although whether VGLUT1v protein is actually translated at the protein level remains unknown. In the present study, VGLUT1v was expressed in insect cells, solubilized, purified to near homogeneity, and its transport activity was examined. Proteoliposomes containing purified VGLUT1v were shown to accumulate glutamate upon imposition of an inside-positive membrane potential (Δψ). The Δψ-driven glutamate uptake activity requires Cl- and its pharmacological profile and kinetics are comparable to those of other VGLUTs. The retinal membrane contained two VGLUT1 moieties with apparent molecular masses of 65 and 57kDa. VGLUT1v-specific antibodies against an inserted 25-amino acid residue sequence identified a 65-kDa immunoreactive polypeptide. Immunohistochemical analysis indicated that VGLUT1v immunoreactivity is present in photoreceptor cells and is associated with synaptic vesicles. VGLUT1v immunoreactivity is also present in pinealocytes, but not in other areas, including the brain. These results indicated that VGLUT1v exists in a functional state in rat photosensitive cells and is involved in glutamatergic chemical transmission.
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Affiliation(s)
- Satomi Moriyama
- Department of Membrane Biochemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama 700-8530, Japan
| | - Masafumi Iharada
- Department of Membrane Biochemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama 700-8530, Japan
| | - Hiroshi Omote
- Department of Membrane Biochemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama 700-8530, Japan
| | - Yoshinori Moriyama
- Department of Membrane Biochemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama 700-8530, Japan.
| | - Miki Hiasa
- Department of Membrane Biochemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama 700-8530, Japan.
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95
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Nibbeling EAR, Delnooz CCS, de Koning TJ, Sinke RJ, Jinnah HA, Tijssen MAJ, Verbeek DS. Using the shared genetics of dystonia and ataxia to unravel their pathogenesis. Neurosci Biobehav Rev 2017; 75:22-39. [PMID: 28143763 DOI: 10.1016/j.neubiorev.2017.01.033] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Revised: 12/09/2016] [Accepted: 01/24/2017] [Indexed: 12/13/2022]
Abstract
In this review we explore the similarities between spinocerebellar ataxias and dystonias, and suggest potentially shared molecular pathways using a gene co-expression network approach. The spinocerebellar ataxias are a group of neurodegenerative disorders characterized by coordination problems caused mainly by atrophy of the cerebellum. The dystonias are another group of neurological movement disorders linked to basal ganglia dysfunction, although evidence is now pointing to cerebellar involvement as well. Our gene co-expression network approach identified 99 shared genes and showed the involvement of two major pathways: synaptic transmission and neurodevelopment. These pathways overlapped in the two disorders, with a large role for GABAergic signaling in both. The overlapping pathways may provide novel targets for disease therapies. We need to prioritize variants obtained by whole exome sequencing in the genes associated with these pathways in the search for new pathogenic variants, which can than be used to help in the genetic counseling of patients and their families.
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Affiliation(s)
- Esther A R Nibbeling
- University of Groningen, University Medical Center Groningen, Department of Genetics, Groningen, The Netherlands
| | - Cathérine C S Delnooz
- University of Groningen, University Medical Center Groningen, Department of Neurology, Groningen, The Netherlands
| | - Tom J de Koning
- University of Groningen, University Medical Center Groningen, Department of Genetics, Groningen, The Netherlands; University of Groningen, University Medical Center Groningen, Department of Neurology, Groningen, The Netherlands
| | - Richard J Sinke
- University of Groningen, University Medical Center Groningen, Department of Genetics, Groningen, The Netherlands
| | - Hyder A Jinnah
- Departments of Neurology, Human Genetics and Pediatrics, Emory Clinic, Atlanta, USA
| | - Marina A J Tijssen
- University of Groningen, University Medical Center Groningen, Department of Neurology, Groningen, The Netherlands
| | - Dineke S Verbeek
- University of Groningen, University Medical Center Groningen, Department of Genetics, Groningen, The Netherlands.
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96
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Schoonover KE, McCollum LA, Roberts RC. Protein Markers of Neurotransmitter Synthesis and Release in Postmortem Schizophrenia Substantia Nigra. Neuropsychopharmacology 2017; 42:540-550. [PMID: 27550734 PMCID: PMC5399235 DOI: 10.1038/npp.2016.164] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Revised: 07/15/2016] [Accepted: 08/13/2016] [Indexed: 12/30/2022]
Abstract
The substantia nigra (SN) provides the largest dopaminergic input to the brain, projects to the striatum (the primary locus of action for antipsychotic medication), and receives GABAergic and glutamatergic inputs. This study used western blot analysis to compare protein levels of tyrosine hydroxylase (TH), glutamate decarboxylase (GAD67), and vesicular glutamate transporters (vGLUT1 and vGLUT2) in postmortem human SN in schizophrenia subjects (n=13) and matched controls (n=12). As a preliminary analysis, the schizophrenia group was subdivided by (1) treatment status: off medication (n=4) or on medication (n=9); or (2) treatment response: treatment resistant (n=5) or treatment responsive (n=4). The combined schizophrenia group had higher TH and GAD67 protein levels than controls (an increase of 69.6%, P=0.01 and 19.5%, P=0.004, respectively). When subdivided by medication status, these increases were found in the on-medication subjects (TH 88.3%, P=0.008; GAD67 40.6%, P=0.003). In contrast, unmedicated schizophrenia subjects had higher vGLUT2 levels than controls (an increase of 28.7%, P=0.041), but vGLUT2 levels were similar between medicated schizophrenia subjects and controls. Treatment-resistant subjects had significantly higher TH and GAD67 levels than controls (an increase of 121.0%, P=0.0003 and 58.7%, P=0.004, respectively). These data suggest increases in dopamine and GABA transmission in the SN in schizophrenia, with a potential relation to treatment and response.
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Affiliation(s)
- Kirsten E Schoonover
- Department of Psychology and Behavioral Neuroscience, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Lesley A McCollum
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Rosalinda C Roberts
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA
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97
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Takami C, Eguchi K, Hori T, Takahashi T. Impact of vesicular glutamate leakage on synaptic transmission at the calyx of Held. J Physiol 2016; 595:1263-1271. [PMID: 27801501 DOI: 10.1113/jp273467] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Accepted: 10/17/2016] [Indexed: 11/08/2022] Open
Abstract
KEY POINTS It is controversial whether glutamate can leak out of vesicles in the nerve terminal. To address this issue, we abolished vesicular glutamate uptake by washing out presynaptic cytosolic glutamate or by blocking vacuolar ATPase activity using bafilomycin A1. In the absence of vesicular glutamate uptake, both spontaneous and nerve-evoked EPSCs underwent a rundown, suggesting that vesicular glutamate can leak out of vesicles. However, the rundown of evoked EPSCs was caused mainly by accumulation of unfilled vesicles after exocytic release of glutamate, suggesting a minor influence of glutamate leakage on synaptic transmission. ABSTRACT Glutamate leaks out of synaptic vesicles when the transvesicular proton gradient is dissipated in isolated vesicle preparations. In the nerve terminal, however, it is controversial whether glutamate can leak out of vesicles. To address this issue, we abolished vesicular glutamate uptake by washing out presynaptic cytosolic glutamate in whole-cell dialysis or by blocking vacuolar ATPase using bafilomycin A1 (Baf) at the calyx of Held in mouse brainstem slices. Presynaptic glutamate washout or Baf application reduced the mean amplitude and frequency of spontaneous miniature (m)EPSCs and the mean amplitude of EPSCs evoked every 10 min. The percentage reduction of mEPSC amplitude was much less than that of EPSC amplitude or mEPSC frequency, and tended to reach a plateau. The mean amplitude of mEPSCs after glutamate washout or Baf application remained high above the detection limit, deduced from the reduction of mEPSC amplitude by the AMPA receptor blocker 6-cyano-7-nitroquinoxaline-2,3-dione. Membrane capacitance measurements from presynaptic terminals indicated no effect of glutamate washout on exocytosis or endocytosis of synaptic vesicles. We conclude that glutamate can leak out of vesicles unless it is continuously taken up from presynaptic cytosol. However, the magnitude of glutamate leakage was small and had only a minor effect on synaptic responses. In contrast, prominent rundowns of EPSC amplitude and mEPSC frequency observed after glutamate washout or Baf application are likely to be caused by accumulation of unfilled vesicles in presynaptic terminals retrieved after spontaneous and evoked glutamate release.
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Affiliation(s)
- Chihiro Takami
- Graduate School of Brain Science and Faculty of Life and Medical Sciences, Doshisha University, Kyotanabe, Kyoto, 610-0394, Japan
| | - Kohgaku Eguchi
- Okinawa Institute of Science and Technology Graduate University, 1919-1, Tancha, Onna-son, Kunigami, Okinawa, 904-0495, Japan
| | - Tetsuya Hori
- Graduate School of Brain Science and Faculty of Life and Medical Sciences, Doshisha University, Kyotanabe, Kyoto, 610-0394, Japan
| | - Tomoyuki Takahashi
- Okinawa Institute of Science and Technology Graduate University, 1919-1, Tancha, Onna-son, Kunigami, Okinawa, 904-0495, Japan
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98
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Piyabhan P, Wannasiri S, Naowaboot J. Bacopa monnieri(Brahmi) improved novel object recognition task and increased cerebral vesicular glutamate transporter type 3 in sub-chronic phencyclidine rat model of schizophrenia. Clin Exp Pharmacol Physiol 2016; 43:1234-1242. [DOI: 10.1111/1440-1681.12658] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 08/01/2016] [Accepted: 08/17/2016] [Indexed: 12/12/2022]
Affiliation(s)
- Pritsana Piyabhan
- Division of Physiology; Department of Preclinical Science; Faculty of Medicine; Thammasat University; Klongluang Pathumthani Thailand
| | - Supaporn Wannasiri
- Division of Physiology; Department of Preclinical Science; Faculty of Medicine; Thammasat University; Klongluang Pathumthani Thailand
| | - Jarinyaporn Naowaboot
- Division of Pharmacology; Department of Preclinical Science; Faculty of Medicine; Thammasat University; Klongluang Pathumthani Thailand
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99
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Cao Z, Xu J, Hulsizer S, Cui Y, Dong Y, Pessah IN. Influence of tetramethylenedisulfotetramine on synchronous calcium oscillations at distinct developmental stages of hippocampal neuronal cultures. Neurotoxicology 2016; 58:11-22. [PMID: 27984050 DOI: 10.1016/j.neuro.2016.10.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Revised: 10/18/2016] [Accepted: 10/18/2016] [Indexed: 12/20/2022]
Abstract
The spatial and temporal patterns of spontaneous synchronous Ca2+ oscillations (SCOs) regulate physiological pathways that influence neuronal development, excitability, and health. Hippocampal neuronal cultures (HN) and neuron/glia co-cultures (HNG) produced from neonatal mice were loaded with Fluo-4/AM and SCOs recorded in real-time using a Fluorescence Imaging Plate Reader at different developmental stages in vitro. HNG showed an earlier onset of SCOs, with low amplitude and low frequency SCOs at 4days in vitro (DIV), whereas HN were quiescent at this point. SCO amplitude peaked at 9 DIV for both cultures. SCO network frequency peaked at 12 DIV in HN, whereas in HNG the frequency peaked at 6 DIV. SCO patterns were associated with the temporal development of neuronal networks and their ratio of glutamatergic to GABAergic markers of excitatory/inhibitory balance. HN and HNG exhibited differential responses to the convulsant tetramethylenedisulfotetramine (TETS) and were highly dependent on DIV. In HN, TETS triggered an acute rise of intracellular Ca2+ (Phase I response) only in 14 DIV and a sustained decrease of SCO frequency with increased amplitude (Phase II response) at all developmental stages. In HNG, TETS decreased the SCO frequency and increased the amplitude at 6 and 14 but not 9 DIV. There was no acute Ca2+ rise (Phase I response) in any age of HNG tested with TETS. These data demonstrated the importance of glia and developmental stage in modulating neuronal responses to TETS. Our results illustrate the applicability of the model for investigating how caged convulsants elicit abnormal network activity during the development of HN and HNG cultures in vitro.
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Affiliation(s)
- Zhengyu Cao
- State Key Laboratory of Natural Medicines & Jiangsu Provincial Key Laboratory for TCM Evaluation and Translational Development, China Pharmaceutical University, Nanjing, 211198, PR China; Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, 95616, United States.
| | - Jian Xu
- State Key Laboratory of Natural Medicines & Jiangsu Provincial Key Laboratory for TCM Evaluation and Translational Development, China Pharmaceutical University, Nanjing, 211198, PR China
| | - Susan Hulsizer
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, 95616, United States
| | - Yanjun Cui
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, 95616, United States
| | - Yao Dong
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, 95616, United States
| | - Isaac N Pessah
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, 95616, United States.
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100
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Weingarten CP, Doraiswamy PM, Fisher MPA. A New Spin on Neural Processing: Quantum Cognition. Front Hum Neurosci 2016; 10:541. [PMID: 27833543 PMCID: PMC5080346 DOI: 10.3389/fnhum.2016.00541] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Accepted: 10/12/2016] [Indexed: 11/20/2022] Open
Affiliation(s)
- Carol P Weingarten
- Department of Psychiatry and Behavioral Sciences, Duke University Medical CenterDurham, NC, USA; Brain Imaging and Analysis Center, Duke University Medical CenterDurham, NC, USA
| | - P Murali Doraiswamy
- Department of Psychiatry and Behavioral Sciences, Duke University Medical CenterDurham, NC, USA; Duke Institute for Brain Sciences, Duke UniversityDurham, NC, USA
| | - Matthew P A Fisher
- Department of Physics, University of California, Santa Barbara Santa Barbara, CA USA
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