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Lamotte JDD, Roqueviere S, Gautier H, Raban E, Bouré C, Fonfria E, Krupp J, Nicoleau C. hiPSC-Derived Neurons Provide a Robust and Physiologically Relevant In Vitro Platform to Test Botulinum Neurotoxins. Front Pharmacol 2021; 11:617867. [PMID: 33519485 PMCID: PMC7840483 DOI: 10.3389/fphar.2020.617867] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Accepted: 11/26/2020] [Indexed: 12/16/2022] Open
Abstract
Botulinum neurotoxins (BoNTs) are zinc metalloproteases that block neurotransmitter release at the neuromuscular junction (NMJ). Their high affinity for motor neurons combined with a high potency have made them extremely effective drugs for the treatment of a variety of neurological diseases as well as for aesthetic applications. Current in vitro assays used for testing and developing BoNT therapeutics include primary rodent cells and immortalized cell lines. Both models have limitations concerning accuracy and physiological relevance. In order to improve the translational value of preclinical data there is a clear need to use more accurate models such as human induced Pluripotent Stem Cells (hiPSC)-derived neuronal models. In this study we have assessed the potential of four different human iPSC-derived neuronal models including Motor Neurons for BoNT testing. We have characterized these models in detail and found that all models express all proteins needed for BoNT intoxication and showed that all four hiPSC-derived neuronal models are sensitive to both serotype A and E BoNT with Motor Neurons being the most sensitive. We showed that hiPSC-derived Motor Neurons expressed authentic markers after only 7 days of culture, are functional and able to form active synapses. When cultivated with myotubes, we demonstrated that they can innervate myotubes and induce contraction, generating an in vitro model of NMJ showing dose-responsive sensitivity BoNT intoxication. Together, these data demonstrate the promise of hiPSC-derived neurons, especially Motor Neurons, for pharmaceutical BoNT testing and development.
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2
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Hua R, Wei H, Liu C, Zhang Y, Liu S, Guo Y, Cui Y, Zhang X, Guo X, Li W, Liu M. FBXO47 regulates telomere-inner nuclear envelope integration by stabilizing TRF2 during meiosis. Nucleic Acids Res 2020; 47:11755-11770. [PMID: 31724724 PMCID: PMC7145685 DOI: 10.1093/nar/gkz992] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 10/11/2019] [Accepted: 10/15/2019] [Indexed: 02/06/2023] Open
Abstract
During meiosis, telomere attachment to the inner nuclear envelope is required for proper pairing of homologous chromosomes and recombination. Here, we identified F-box protein 47 (FBXO47) as a regulator of the telomeric shelterin complex that is specifically expressed during meiotic prophase I. Knockout of Fbxo47 in mice leads to infertility in males. We found that the Fbxo47 deficient spermatocytes are unable to form a complete synaptonemal complex. FBXO47 interacts with TRF1/2, and the disruption of Fbxo47 destabilizes TRF2, leading to unstable telomere attachment and slow traversing through the bouquet stage. Our findings uncover a novel mechanism of FBXO47 in telomeric shelterin subunit stabilization during meiosis.
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Affiliation(s)
- Rong Hua
- State Key Laboratory of Reproductive Medicine, Center for Global Health, Nanjing Medical University, Nanjing, Jiangsu, 211166, P.R. China
| | - Huafang Wei
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, P.R. China.,University of Chinese Academy of Sciences, Beijing 100049, P.R. China
| | - Chao Liu
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, P.R. China.,University of Chinese Academy of Sciences, Beijing 100049, P.R. China
| | - Yue Zhang
- State Key Laboratory of Reproductive Medicine, Center for Global Health, Nanjing Medical University, Nanjing, Jiangsu, 211166, P.R. China
| | - Siyu Liu
- State Key Laboratory of Reproductive Medicine, Center for Global Health, Nanjing Medical University, Nanjing, Jiangsu, 211166, P.R. China
| | - Yueshuai Guo
- State Key Laboratory of Reproductive Medicine, Center for Global Health, Nanjing Medical University, Nanjing, Jiangsu, 211166, P.R. China
| | - Yiqiang Cui
- State Key Laboratory of Reproductive Medicine, Center for Global Health, Nanjing Medical University, Nanjing, Jiangsu, 211166, P.R. China
| | - Xin Zhang
- State Key Laboratory of Reproductive Medicine, Center for Global Health, Nanjing Medical University, Nanjing, Jiangsu, 211166, P.R. China
| | - Xuejiang Guo
- State Key Laboratory of Reproductive Medicine, Center for Global Health, Nanjing Medical University, Nanjing, Jiangsu, 211166, P.R. China
| | - Wei Li
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, P.R. China.,University of Chinese Academy of Sciences, Beijing 100049, P.R. China
| | - Mingxi Liu
- State Key Laboratory of Reproductive Medicine, Center for Global Health, Nanjing Medical University, Nanjing, Jiangsu, 211166, P.R. China
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3
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Pregnant rats exposed to low-level methylmercury exhibit cerebellar synaptic and neuritic remodeling during the perinatal period. Arch Toxicol 2020; 94:1335-1347. [DOI: 10.1007/s00204-020-02696-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Accepted: 03/02/2020] [Indexed: 12/14/2022]
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4
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Simó A, Cilleros-Mañé V, Just-Borràs L, Hurtado E, Nadal L, Tomàs M, Garcia N, Lanuza MA, Tomàs J. nPKCε Mediates SNAP-25 Phosphorylation of Ser-187 in Basal Conditions and After Synaptic Activity at the Neuromuscular Junction. Mol Neurobiol 2019; 56:5346-5364. [PMID: 30607888 DOI: 10.1007/s12035-018-1462-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Accepted: 12/18/2018] [Indexed: 12/14/2022]
Abstract
Protein kinase C (PKC) and substrates like SNAP-25 regulate neurotransmission. At the neuromuscular junction (NMJ), PKC promotes neurotransmitter release during synaptic activity. Thirty minutes of muscle contraction enhances presynaptic PKC isoform levels, specifically cPKCβI and nPKCε, through retrograde BDNF/TrkB signaling. This establishes a larger pool of these PKC isoforms ready to promote neuromuscular transmission. The PKC phosphorylation site in SNAP-25 has been mapped to the serine 187 (Ser-187), which is known to enhance calcium-dependent neurotransmitter release in vitro. Here, we localize SNAP-25 at the NMJ and investigate whether cPKCβI and/or nPKCε regulate SNAP-25 phosphorylation. We also investigate whether nerve and muscle cell activities regulate differently SNAP-25 phosphorylation and the involvement of BDNF/TrkB signaling. Our results demonstrate that nPKCε isoform is essential to positively regulate SNAP-25 phosphorylation on Ser-187 and that muscle contraction prevents it. TrkB and cPKCβI do not regulate SNAP-25 protein level or its phosphorylation during neuromuscular activity. The results provide evidence that nerve terminals need both pre- and postsynaptic activities to modulate SNAP-25 phosphorylation and ensure an accurate neurotransmission process.
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Affiliation(s)
- Anna Simó
- Unitat d'Histologia i Neurobiologia (UHNEUROB), Facultat de Medicina i Ciències de la Salut, Universitat Rovira i Virgili, Sant Llorenç 21, 43201, Reus, Spain
| | - Victor Cilleros-Mañé
- Unitat d'Histologia i Neurobiologia (UHNEUROB), Facultat de Medicina i Ciències de la Salut, Universitat Rovira i Virgili, Sant Llorenç 21, 43201, Reus, Spain
| | - Laia Just-Borràs
- Unitat d'Histologia i Neurobiologia (UHNEUROB), Facultat de Medicina i Ciències de la Salut, Universitat Rovira i Virgili, Sant Llorenç 21, 43201, Reus, Spain
| | - Erica Hurtado
- Unitat d'Histologia i Neurobiologia (UHNEUROB), Facultat de Medicina i Ciències de la Salut, Universitat Rovira i Virgili, Sant Llorenç 21, 43201, Reus, Spain
| | - Laura Nadal
- Unitat d'Histologia i Neurobiologia (UHNEUROB), Facultat de Medicina i Ciències de la Salut, Universitat Rovira i Virgili, Sant Llorenç 21, 43201, Reus, Spain
| | - Marta Tomàs
- Unitat d'Histologia i Neurobiologia (UHNEUROB), Facultat de Medicina i Ciències de la Salut, Universitat Rovira i Virgili, Sant Llorenç 21, 43201, Reus, Spain
| | - Neus Garcia
- Unitat d'Histologia i Neurobiologia (UHNEUROB), Facultat de Medicina i Ciències de la Salut, Universitat Rovira i Virgili, Sant Llorenç 21, 43201, Reus, Spain
| | - Maria A Lanuza
- Unitat d'Histologia i Neurobiologia (UHNEUROB), Facultat de Medicina i Ciències de la Salut, Universitat Rovira i Virgili, Sant Llorenç 21, 43201, Reus, Spain.
| | - Josep Tomàs
- Unitat d'Histologia i Neurobiologia (UHNEUROB), Facultat de Medicina i Ciències de la Salut, Universitat Rovira i Virgili, Sant Llorenç 21, 43201, Reus, Spain.
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5
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Pozzi D, Corradini I, Matteoli M. The Control of Neuronal Calcium Homeostasis by SNAP-25 and its Impact on Neurotransmitter Release. Neuroscience 2018; 420:72-78. [PMID: 30476527 DOI: 10.1016/j.neuroscience.2018.11.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Revised: 11/05/2018] [Accepted: 11/08/2018] [Indexed: 01/14/2023]
Abstract
The process of neurotransmitter release is central to the control of cell-to-cell communication in brain. SNAP-25 is a component of the SNARE complex, which, together with syntaxin-1 and synaptobrevin, mediates synaptic vesicle fusion with the plasma membrane. The genetic ablation of the protein or its proteolytic cleavage by botulinum neurotoxins results in a complete block of synaptic transmission. In the last years, several evidences have indicated that SNAP-25 also plays additional modulatory roles in neurotransmission through the control of voltage-gated calcium channels and presynaptic calcium ion concentration. Consistently, reduced levels of the protein affect presynaptic calcium homeostasis and result in pathologically enhanced glutamate exocytosis. The SNAP-25-dependent alterations of synaptic calcium dynamics may have direct impact on the development of neuropsychiatric disorders where the Snap-25 gene has been found to be involved.
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Affiliation(s)
- Davide Pozzi
- Humanitas University, Via Rita Levi Montalcini, 4, 20090 Pieve Emanuele, Milano, Italy; IRCCS Humanitas, via Manzoni 56, 20089 Rozzano, Italy.
| | - Irene Corradini
- CNR Institute of Neuroscience, via Vanvitelli 32, 20129 Milano, Italy
| | - Michela Matteoli
- Humanitas University, Via Rita Levi Montalcini, 4, 20090 Pieve Emanuele, Milano, Italy; IRCCS Humanitas, via Manzoni 56, 20089 Rozzano, Italy.
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6
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Hussain S, Ringsevjen H, Schupp M, Hvalby Ø, Sørensen JB, Jensen V, Davanger S. A possible postsynaptic role for SNAP-25 in hippocampal synapses. Brain Struct Funct 2018; 224:521-532. [PMID: 30377802 DOI: 10.1007/s00429-018-1782-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Accepted: 10/19/2018] [Indexed: 12/17/2022]
Abstract
The SNARE protein SNAP-25 is well documented as regulator of presynaptic vesicle exocytosis. Increasing evidence suggests roles for SNARE proteins in postsynaptic trafficking of glutamate receptors as a basic mechanism in synaptic plasticity. Despite these indications, detailed quantitative subsynaptic localization studies of SNAP-25 have never been performed. Here, we provide novel electron microscopic data of SNAP-25 localization in postsynaptic spines. In addition to its expected presynaptic localization, we show that the protein is also present in the postsynaptic density (PSD), the postsynaptic lateral membrane and on small vesicles in the postsynaptic cytoplasm. We further investigated possible changes in synaptic SNAP-25 protein expression after hippocampal long-term potentiation (LTP). Quantitative analysis of immunogold-labeled electron microscopy sections did not show statistically significant changes of SNAP-25 gold particle densities 1 h after LTP induction, indicating that local trafficking of SNAP-25 does not play a role in the early phases of LTP. However, the strong expression of SNAP-25 in postsynaptic plasma membranes suggests a function of the protein in postsynaptic vesicle exocytosis and a possible role in hippocampal synaptic plasticity.
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Affiliation(s)
- S Hussain
- Division of Anatomy, Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - H Ringsevjen
- Division of Anatomy, Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - M Schupp
- Department of Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Ø Hvalby
- Division of Physiology, Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - J B Sørensen
- Department of Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - V Jensen
- Division of Physiology, Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - S Davanger
- Division of Anatomy, Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway. .,Laboratory of Synaptic Plasticity, Division of Anatomy, Institute of Basic Medical Sciences, P.O.Box 1105, Blindern, 0317, Oslo, Norway.
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7
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Critical role for Annexin A7 in secondary brain injury mediated by its phosphorylation after experimental intracerebral hemorrhage in rats. Neurobiol Dis 2018; 110:82-92. [DOI: 10.1016/j.nbd.2017.11.012] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 10/14/2017] [Accepted: 11/27/2017] [Indexed: 01/27/2023] Open
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8
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Li C, Ma Y, Zhang K, Gu J, Tang F, Chen S, Cao L, Li S, Jin Y. Aberrant transcriptional networks in step-wise neurogenesis of paroxysmal kinesigenic dyskinesia-induced pluripotent stem cells. Oncotarget 2018; 7:53611-53627. [PMID: 27449084 PMCID: PMC5288209 DOI: 10.18632/oncotarget.10680] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Accepted: 06/30/2016] [Indexed: 12/31/2022] Open
Abstract
Paroxysmal kinesigenic dyskinesia (PKD) is an episodic movement disorder with autosomal-dominant inheritance and marked variability in clinical manifestations. Proline-rich transmembrane protein 2 (PRRT2) has been identified as a causative gene of PKD, but the molecular mechanism underlying the pathogenesis of PKD still remains a mystery. The phenotypes and transcriptional patterns of the PKD disease need further clarification. Here, we report the generation and neural differentiation of iPSC lines from two familial PKD patients with c.487C>T (p. Gln163X) and c.573dupT (p. Gly192Trpfs*8) PRRT2 mutations, respectively. Notably, an extremely lower efficiency in neural conversion from PKD-iPSCs than control-iPSCs is observed by a step-wise neural differentiation method of dual inhibition of SMAD signaling. Moreover, we show the high expression level of PRRT2 throughout the human brain and the expression pattern of PRRT2 in other human tissues for the first time. To gain molecular insight into the development of the disease, we conduct global gene expression profiling of PKD cells at four different stages of neural induction and identify altered gene expression patterns, which peculiarly reflect dysregulated neural transcriptome signatures and a differentiation tendency to mesodermal development, in comparison to control-iPSCs. Additionally, functional and signaling pathway analyses indicate significantly different cell fate determination between PKD-iPSCs and control-iPSCs. Together, the establishment of PKD-specific in vitro models and the illustration of transcriptome features in PKD cells would certainly help us with better understanding of the defects in neural conversion as well as further investigations in the pathogenesis of the PKD disease.
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Affiliation(s)
- Chun Li
- Laboratory of Molecular Developmental Biology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Yu Ma
- Laboratory of Molecular Developmental Biology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Kunshan Zhang
- Stem Cell Translational Research Center, Tongji Hospital, Tongji University School of Medicine, Shanghai 200065, China
| | - Junjie Gu
- Laboratory of Molecular Developmental Biology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Fan Tang
- Laboratory of Molecular Developmental Biology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Shengdi Chen
- Department of Neurology, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.,Key Laboratory of Stem Cell Biology, Center for The Excellence in Molecular and Cell Sciences, Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences and Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Li Cao
- Department of Neurology, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Siguang Li
- Stem Cell Translational Research Center, Tongji Hospital, Tongji University School of Medicine, Shanghai 200065, China.,Collaborative Innovation Center for Brain Science, Tongji University, Shanghai 200092, China
| | - Ying Jin
- Laboratory of Molecular Developmental Biology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.,Key Laboratory of Stem Cell Biology, Center for The Excellence in Molecular and Cell Sciences, Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences and Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
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9
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van der Stijl R, Withoff S, Verbeek DS. Spinocerebellar ataxia: miRNAs expose biological pathways underlying pervasive Purkinje cell degeneration. Neurobiol Dis 2017; 108:148-158. [PMID: 28823930 DOI: 10.1016/j.nbd.2017.08.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Revised: 07/21/2017] [Accepted: 08/16/2017] [Indexed: 01/09/2023] Open
Abstract
Recent work has demonstrated the importance of miRNAs in the pathogenesis of various brain disorders including the neurodegenerative disorder spinocerebellar ataxia (SCA). This review focuses on the role of miRNAs in the shared pathogenesis of the different SCA types. We examine the novel findings of a recent cell-type-specific RNA-sequencing study in mouse brain and discuss how the identification of Purkinje-cell-enriched miRNAs highlights biological pathways that expose the mechanisms behind pervasive Purkinje cell degeneration in SCA. These key pathways are likely to contain targets for therapeutic development and represent potential candidate genes for genetically unsolved SCAs.
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Affiliation(s)
- Rogier van der Stijl
- Department of Genetics, University of Groningen, University Medical Centre Groningen, Groningen, The Netherlands
| | - Sebo Withoff
- Department of Genetics, University of Groningen, University Medical Centre Groningen, Groningen, The Netherlands
| | - Dineke S Verbeek
- Department of Genetics, University of Groningen, University Medical Centre Groningen, Groningen, The Netherlands.
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10
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Ogata K, Kushida M, Miyata K, Sumida K, Takeda S, Izawa T, Kuwamura M, Yamate J. Alteration of microRNA expressions in the pons and medulla in rats after 3,3'-iminodipropionitrile administration. J Toxicol Pathol 2016; 29:229-236. [PMID: 27821907 PMCID: PMC5097965 DOI: 10.1293/tox.2016-0019] [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] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Accepted: 05/02/2016] [Indexed: 11/19/2022] Open
Abstract
Although 3,3′-iminodipropionitrile (IDPN) is widely used as a neurotoxicant to cause axonopathy due to accumulation of neurofilaments in several rodent models, its mechanism of neurotoxicity has not been fully understood. In particular, no information regarding microRNA (miRNA) alteration associated with IDPN is available. This study was conducted to reveal miRNA alteration related to IDPN-induced neurotoxicity. Rats were administered IDPN (20, 50, or 125 mg/kg/day) orally for 3, 7, and 14 days. Histopathological features were investigated using immunohistochemistry for neurofilaments and glial cells, and miRNA alterations were analyzed by microarray and reverse transcription polymerase chain reaction. Nervous symptoms such as ataxic gait and head bobbing were observed from Day 9 at 125 mg/kg. Axonal swelling due to accumulation of neurofilaments was observed especially in the pons, medulla, and spinal cord on Day 7 at 125 mg/kg and on Day 14 at 50 and 125 mg/kg. Furthermore, significant upregulation of miR-547* was observed in the pons and medulla in treated animals only on Day 14 at 125 mg/kg. This is the first report indicating that miR-547* is associated with IDPN-induced neurotoxicity, especially in an advanced stage of axonopathy.
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Affiliation(s)
- Keiko Ogata
- Environmental Health Science Laboratory, Sumitomo Chemical Co., Ltd., Osaka 554-8558, Japan; Laboratory of Veterinary Pathology, Division of Veterinary Sciences, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Osaka 598-8531, Japan
| | - Masahiko Kushida
- Environmental Health Science Laboratory, Sumitomo Chemical Co., Ltd., Osaka 554-8558, Japan
| | - Kaori Miyata
- Environmental Health Science Laboratory, Sumitomo Chemical Co., Ltd., Osaka 554-8558, Japan
| | - Kayo Sumida
- Environmental Health Science Laboratory, Sumitomo Chemical Co., Ltd., Osaka 554-8558, Japan
| | - Shuji Takeda
- Environmental Health Science Laboratory, Sumitomo Chemical Co., Ltd., Osaka 554-8558, Japan
| | - Takeshi Izawa
- Laboratory of Veterinary Pathology, Division of Veterinary Sciences, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Osaka 598-8531, Japan
| | - Mitsuru Kuwamura
- Laboratory of Veterinary Pathology, Division of Veterinary Sciences, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Osaka 598-8531, Japan
| | - Jyoji Yamate
- Laboratory of Veterinary Pathology, Division of Veterinary Sciences, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Osaka 598-8531, Japan
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11
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Knocking down of heat-shock protein 27 directs differentiation of functional glutamatergic neurons from placenta-derived multipotent cells. Sci Rep 2016; 6:30314. [PMID: 27444754 PMCID: PMC4957209 DOI: 10.1038/srep30314] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Accepted: 07/04/2016] [Indexed: 01/06/2023] Open
Abstract
This study presents human placenta-derived multipotent cells (PDMCs) as a source from which functional glutamatergic neurons can be derived. We found that the small heat-shock protein 27 (HSP27) was downregulated during the neuronal differentiation process. The in vivo temporal and spatial profiles of HSP27 expression were determined and showed inverted distributions with neuronal proteins during mouse embryonic development. Overexpression of HSP27 in stem cells led to the arrest of neuronal differentiation; however, the knockdown of HSP27 yielded a substantially enhanced ability of PDMCs to differentiate into neurons. These neurons formed synaptic networks and showed positive staining for multiple neuronal markers. Additionally, cellular phenomena including the absence of apoptosis and rare proliferation in HSP27-silenced PDMCs, combined with molecular events such as cleaved caspase-3 and the loss of stemness with cleaved Nanog, indicated that HSP27 is located upstream of neuronal differentiation and constrains that process. Furthermore, the induced neurons showed increasing intracellular calcium concentrations upon glutamate treatment. These differentiated cells co-expressed the N-methyl-D-aspartate receptor, vesicular glutamate transporter, and synaptosomal-associated protein 25 but did not show expression of tyrosine hydroxylase, choline acetyltransferase or glutamate decarboxylase 67. Therefore, we concluded that HSP27-silenced PDMCs differentiated into neurons possessing the characteristics of functional glutamatergic neurons.
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12
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Fontaine SN, Zheng D, Sabbagh JJ, Martin MD, Chaput D, Darling A, Trotter JH, Stothert AR, Nordhues BA, Lussier A, Baker J, Shelton L, Kahn M, Blair LJ, Stevens SM, Dickey CA. DnaJ/Hsc70 chaperone complexes control the extracellular release of neurodegenerative-associated proteins. EMBO J 2016; 35:1537-49. [PMID: 27261198 PMCID: PMC4946142 DOI: 10.15252/embj.201593489] [Citation(s) in RCA: 129] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Revised: 04/25/2016] [Accepted: 04/27/2016] [Indexed: 12/12/2022] Open
Abstract
It is now known that proteins associated with neurodegenerative disease can spread throughout the brain in a prionlike manner. However, the mechanisms regulating the trans-synaptic spread propagation, including the neuronal release of these proteins, remain unknown. The interaction of neurodegenerative disease-associated proteins with the molecular chaperone Hsc70 is well known, and we hypothesized that much like disaggregation, refolding, degradation, and even normal function, Hsc70 may dictate the extracellular fate of these proteins. Here, we show that several proteins, including TDP-43, α-synuclein, and the microtubule-associated protein tau, can be driven out of the cell by an Hsc70 co-chaperone, DnaJC5. In fact, DnaJC5 overexpression induced tau release in cells, neurons, and brain tissue, but only when activity of the chaperone Hsc70 was intact and when tau was able to associate with this chaperone. Moreover, release of tau from neurons was reduced in mice lacking the DnaJC5 gene and when the complement of DnaJs in the cell was altered. These results demonstrate that the dynamics of DnaJ/Hsc70 complexes are critically involved in the release of neurodegenerative disease proteins.
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Affiliation(s)
- Sarah N Fontaine
- Department of Molecular Medicine, College of Medicine, Byrd Alzheimer's Institute, University of South Florida, Tampa, FL, USA James A. Haley Veteran's Hospital, Tampa, FL, USA
| | - Dali Zheng
- Department of Molecular Medicine, College of Medicine, Byrd Alzheimer's Institute, University of South Florida, Tampa, FL, USA
| | - Jonathan J Sabbagh
- Department of Molecular Medicine, College of Medicine, Byrd Alzheimer's Institute, University of South Florida, Tampa, FL, USA James A. Haley Veteran's Hospital, Tampa, FL, USA
| | - Mackenzie D Martin
- Department of Molecular Medicine, College of Medicine, Byrd Alzheimer's Institute, University of South Florida, Tampa, FL, USA James A. Haley Veteran's Hospital, Tampa, FL, USA
| | - Dale Chaput
- Department of Cell, Molecular and Life Sciences, University of South Florida, Tampa, FL, USA
| | - April Darling
- Department of Molecular Medicine, College of Medicine, Byrd Alzheimer's Institute, University of South Florida, Tampa, FL, USA
| | - Justin H Trotter
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA, USA
| | - Andrew R Stothert
- Department of Molecular Medicine, College of Medicine, Byrd Alzheimer's Institute, University of South Florida, Tampa, FL, USA
| | - Bryce A Nordhues
- Department of Molecular Medicine, College of Medicine, Byrd Alzheimer's Institute, University of South Florida, Tampa, FL, USA
| | - April Lussier
- Department of Molecular Medicine, College of Medicine, Byrd Alzheimer's Institute, University of South Florida, Tampa, FL, USA
| | - Jeremy Baker
- Department of Molecular Medicine, College of Medicine, Byrd Alzheimer's Institute, University of South Florida, Tampa, FL, USA
| | - Lindsey Shelton
- Department of Molecular Medicine, College of Medicine, Byrd Alzheimer's Institute, University of South Florida, Tampa, FL, USA
| | - Mahnoor Kahn
- Department of Molecular Medicine, College of Medicine, Byrd Alzheimer's Institute, University of South Florida, Tampa, FL, USA
| | - Laura J Blair
- Department of Molecular Medicine, College of Medicine, Byrd Alzheimer's Institute, University of South Florida, Tampa, FL, USA
| | - Stanley M Stevens
- Department of Cell, Molecular and Life Sciences, University of South Florida, Tampa, FL, USA
| | - Chad A Dickey
- Department of Molecular Medicine, College of Medicine, Byrd Alzheimer's Institute, University of South Florida, Tampa, FL, USA James A. Haley Veteran's Hospital, Tampa, FL, USA
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Li M, Niu F, Zhu X, Wu X, Shen N, Peng X, Liu Y. PRRT2 Mutant Leads to Dysfunction of Glutamate Signaling. Int J Mol Sci 2015; 16:9134-51. [PMID: 25915028 PMCID: PMC4463582 DOI: 10.3390/ijms16059134] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Revised: 04/10/2015] [Accepted: 04/13/2015] [Indexed: 01/28/2023] Open
Abstract
Paroxysmal kinesigenic choreoathetosis (PKC) is an inherited disease of the nervous system. We previously identified PRRT2 as the causative gene of PKC. However, as little is known about the function of PRRT2, elucidating its function will benefit not only PKC studies, but also many other related disorders. Here, we reveal higher levels of glutamate in the plasma of PKC patients and the culture medium of neurons following knock-out Prrt2 expression. Using double immunostaining assays we confirm Prrt2 is located at the glutamatergic neurons in accordance with its function. Our co-immunoprecipitation assays reveal mutant PRRT2 interferes with SNAP25 and GRIA1 interactions, respectively. Furthermore, using live-labeling techniques, we confirmed co-transfection with mutant PRRT2 caused an increase in GRIA1 distribution on the cell surface. Therefore, our results suggest that mutant PRRT2, probably through its weakened interaction with SNAP25, affects glutamate signaling and glutamate receptor activity, resulting in the increase of glutamate release and subsequent neuronal hyperexcitability.
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Affiliation(s)
- Ming Li
- State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing 100005, China.
| | - Fenghe Niu
- State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing 100005, China.
| | - Xilin Zhu
- State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing 100005, China.
| | - Xiaopan Wu
- State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing 100005, China.
| | - Ning Shen
- State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing 100005, China.
| | - Xiaozhong Peng
- State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing 100005, China.
| | - Ying Liu
- State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing 100005, China.
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Distribution of SNAP25, VAMP1 and VAMP2 in mature and developing deep cerebellar nuclei after estrogen administration. Neuroscience 2014; 266:102-15. [DOI: 10.1016/j.neuroscience.2014.02.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2014] [Revised: 02/04/2014] [Accepted: 02/06/2014] [Indexed: 11/19/2022]
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Puglisi F, Vanni V, Ponterio G, Tassone A, Sciamanna G, Bonsi P, Pisani A, Mandolesi G. Torsin A Localization in the Mouse Cerebellar Synaptic Circuitry. PLoS One 2013; 8:e68063. [PMID: 23840813 PMCID: PMC3686744 DOI: 10.1371/journal.pone.0068063] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Accepted: 05/24/2013] [Indexed: 11/19/2022] Open
Abstract
Torsin A (TA) is a ubiquitous protein belonging to the superfamily of proteins called "ATPases associated with a variety of cellular activities" (AAA(+) ATPase). To date, a great deal of attention has been focused on neuronal TA since its mutant form causes early-onset (DYT1) torsion dystonia, an inherited movement disorder characterized by sustained muscle contractions and abnormal postures. Interestingly, it has been proposed that TA, by interacting with the cytoskeletal network, may contribute to the control of neurite outgrowth and/or by acting as a chaperone at synapses could affect synaptic vesicle turnover and neurotransmitter release. Accordingly, both its peculiar developmental expression in striatum and cerebellum and evidence from DYT1 knock-in mice suggest that TA may influence dendritic arborization and synaptogenesis in the brain. Therefore, to better understand TA function a detailed description of its localization at synaptic level is required. Here, we characterized by means of rigorous quantitative confocal analysis TA distribution in the mouse cerebellum at postnatal day 14 (P14), when both cerebellar synaptogenesis and TA expression peak. We observed that the protein is broadly distributed both in cerebellar cortex and in the deep cerebellar nuclei (DCN). Of note, Purkinje cells (PC) express high levels of TA also in the spines and axonal terminals. In addition, abundant expression of the protein was found in the main GABA-ergic and glutamatergic inputs of the cerebellar cortex. Finally, TA was observed also in glial cells, a cellular population little explored so far. These results extend our knowledge on TA synaptic localization providing a clue to its potential role in synaptic development.
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Affiliation(s)
- Francesca Puglisi
- Department of Systems Medicine, University of Rome Tor Vergata/Laboratory of Neurophysiology and Synaptic Plasticity, Fondazione Santa Lucia, Rome, Italy
| | - Valentina Vanni
- Department of Systems Medicine, University of Rome Tor Vergata/Laboratory of Neurophysiology and Synaptic Plasticity, Fondazione Santa Lucia, Rome, Italy
| | - Giulia Ponterio
- Department of Systems Medicine, University of Rome Tor Vergata/Laboratory of Neurophysiology and Synaptic Plasticity, Fondazione Santa Lucia, Rome, Italy
| | - Annalisa Tassone
- Department of Systems Medicine, University of Rome Tor Vergata/Laboratory of Neurophysiology and Synaptic Plasticity, Fondazione Santa Lucia, Rome, Italy
| | - Giuseppe Sciamanna
- Department of Systems Medicine, University of Rome Tor Vergata/Laboratory of Neurophysiology and Synaptic Plasticity, Fondazione Santa Lucia, Rome, Italy
| | - Paola Bonsi
- Department of Systems Medicine, University of Rome Tor Vergata/Laboratory of Neurophysiology and Synaptic Plasticity, Fondazione Santa Lucia, Rome, Italy
| | - Antonio Pisani
- Department of Systems Medicine, University of Rome Tor Vergata/Laboratory of Neurophysiology and Synaptic Plasticity, Fondazione Santa Lucia, Rome, Italy
- * E-mail:
| | - Georgia Mandolesi
- Department of Systems Medicine, University of Rome Tor Vergata/Laboratory of Neurophysiology and Synaptic Plasticity, Fondazione Santa Lucia, Rome, Italy
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Reduced SNAP-25 alters short-term plasticity at developing glutamatergic synapses. EMBO Rep 2013; 14:645-51. [PMID: 23732542 DOI: 10.1038/embor.2013.75] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2012] [Revised: 05/13/2013] [Accepted: 05/14/2013] [Indexed: 02/07/2023] Open
Abstract
SNAP-25 is a key component of the synaptic-vesicle fusion machinery, involved in several psychiatric diseases including schizophrenia and ADHD. SNAP-25 protein expression is lower in different brain areas of schizophrenic patients and in ADHD mouse models. How the reduced expression of SNAP-25 alters the properties of synaptic transmission, leading to a pathological phenotype, is unknown. We show that, unexpectedly, halved SNAP-25 levels at 13-14 DIV not only fail to impair synaptic transmission but instead enhance evoked glutamatergic neurotransmission. This effect is possibly dependent on presynaptic voltage-gated calcium channel activity and is not accompanied by changes in spontaneous quantal events or in the pool of readily releasable synaptic vesicles. Notably, synapses of 13-14 DIV neurons with reduced SNAP-25 expression show paired-pulse depression as opposed to paired-pulse facilitation occurring in their wild-type counterparts. This phenotype disappears with synapse maturation. As alterations in short-term plasticity represent a new mechanism contributing to cognitive impairments in intellectual disabilities, our data provide mechanistic clues for neuronal circuit alterations in psychiatric diseases characterized by reduced expression of SNAP-25.
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Abstract
The concept of a tripartite synapse including a presynaptic terminal, a postsynaptic spine, and an astrocytic process that responds to neuronal activity by fast gliotransmitter release, confers to the electrically silent astrocytes an active role in information processing. However, the mechanisms of gliotransmitter release are still highly controversial. The reported expression of all three vesicular glutamate transporters (VGLUT1-3) by astrocytes suggests that astrocytes, like neurons, may release glutamate by exocytosis. However, the demonstration of astrocytic VGLUT expression is largely based on immunostaining, and the possibility of nonspecific labeling needs to be systematically addressed. We therefore examined the expression of VGLUT1-3 in astrocytes, both in culture and in situ. We used Western blots and single-vesicle imaging by total internal reflection fluorescence microscopy in live cultured astrocytes, and confocal microscopy, at the cellular level in cortical, hippocampal, and cerebellar brain slices, combined with quantitative image analysis. Control experiments were systematically performed in cultured astrocytes using wild-type, VGLUT1-3 knock-out, VGLUT1(Venus) knock-in, and VGLUT2-EGFP transgenic mice. In fixed brain slices, we quantified the degree of overlap between VGLUT1-3 and neuronal or astrocytic markers, both in an object-based manner using fluorescence line profiles, and in a pixel-based manner using dual-color scatter plots followed by the calculation of Pearson's correlation coefficient over all pixels with intensities significantly different from background. Our data provide no evidence in favor of the expression of any of the three VGLUTs by gray matter protoplasmic astrocytes of the primary somatosensory cortex, the thalamic ventrobasal nucleus, the hippocampus, and the cerebellum.
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Neuronal Nogo-A negatively regulates dendritic morphology and synaptic transmission in the cerebellum. Proc Natl Acad Sci U S A 2012; 110:1083-8. [PMID: 23277570 DOI: 10.1073/pnas.1214255110] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Neuronal signal integration as well as synaptic transmission and plasticity highly depend on the morphology of dendrites and their spines. Nogo-A is a membrane protein enriched in the adult central nervous system (CNS) myelin, where it restricts the capacity of axons to grow and regenerate after injury. Nogo-A is also expressed by certain neurons, in particular during development, but its physiological function in this cell type is less well understood. We addressed this question in the cerebellum, where Nogo-A is transitorily highly expressed in the Purkinje cells (PCs) during early postnatal development. We used general genetic ablation (KO) as well as selective overexpression of Nogo-A in PCs to analyze its effect on dendritogenesis and on the formation of their main input synapses from parallel (PFs) and climbing fibers (CFs). PC dendritic trees were larger and more complex in Nogo-A KO mice and smaller than in wild-type in Nogo-A overexpressing PCs. Nogo-A KO resulted in premature soma-to-dendrite translocation of CFs and an enlargement of the CF territory in the molecular layer during development. Although spine density was not influenced by Nogo-A, the size of postsynaptic densities of PF-PC synapses was negatively correlated with the Nogo-A expression level. Electrophysiological studies revealed that Nogo-A negatively regulates the strength of synaptic transmission at the PF-PC synapse. Thus, Nogo-A appears as a negative regulator of PC input synapses, which orchestrates cerebellar connectivity through regulation of synapse morphology and the size of the PC dendritic tree.
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VAMP-2, SNAP-25A/B and syntaxin-1 in glutamatergic and GABAergic synapses of the rat cerebellar cortex. BMC Neurosci 2011; 12:118. [PMID: 22094010 PMCID: PMC3228762 DOI: 10.1186/1471-2202-12-118] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2011] [Accepted: 11/17/2011] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND The aim of this study was to assess the distribution of key SNARE proteins in glutamatergic and GABAergic synapses of the adult rat cerebellar cortex using light microscopy immunohistochemical techniques. Analysis was made of co-localizations of vGluT-1 and vGluT-2, vesicular transporters of glutamate and markers of glutamatergic synapses, or GAD, the GABA synthetic enzyme and marker of GABAergic synapses, with VAMP-2, SNAP-25A/B and syntaxin-1. RESULTS The examined SNARE proteins were found to be diffusely expressed in glutamatergic synapses, whereas they were rarely observed in GABAergic synapses. However, among glutamatergic synapses, subpopulations which did not contain VAMP-2, SNAP-25A/B and syntaxin-1 were detected. They included virtually all the synapses established by terminals of climbing fibres (immunoreactive for vGluT-2) and some synapses established by terminals of parallel and mossy fibres (immunoreactive for vGluT-1, and for vGluT-1 and 2, respectively). The only GABA synapses expressing the SNARE proteins studied were the synapses established by axon terminals of basket neurons. CONCLUSION The present study supplies a detailed morphological description of VAMP-2, SNAP-25A/B and syntaxin-1 in the different types of glutamatergic and GABAergic synapses of the rat cerebellar cortex. The examined SNARE proteins characterize most of glutamatergic synapses and only one type of GABAergic synapses. In the subpopulations of glutamatergic and GABAergic synapses lacking the SNARE protein isoforms examined, alternative mechanisms for regulating trafficking of synaptic vesicles may be hypothesized, possibly mediated by different isoforms or homologous proteins.
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Type VI adenylyl cyclase regulates neurite extension by binding to Snapin and Snap25. Mol Cell Biol 2011; 31:4874-86. [PMID: 21986494 DOI: 10.1128/mcb.05593-11] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
3'-5'-Cyclic AMP (cAMP) is an important second messenger which regulates neurite outgrowth. We demonstrate here that type VI adenylyl cyclase (AC6), an enzyme which catalyzes cAMP synthesis, regulates neurite outgrowth by direct interaction with a binding protein (Snapin) of Snap25 at the N terminus of AC6 (AC6-N). We first showed that AC6 expression increased during postnatal brain development. In primary hippocampal neurons and Neuro2A cells, elevated AC6 expression suppressed neurite outgrowth, whereas the downregulation or genetic removal of AC6 promoted neurite extension. An AC6 variant (AC6-N5) that contains the N terminus of AC5 had no effect, indicating the importance of AC6-N. The downregulation of endogenous Snapin or the overexpression of a Snapin mutant (Snap(Δ33-51)) that does not bind to AC6, or another Snapin mutant (Snapin(S50A)) that does not interact with Snap25, reversed the inhibitory effect of AC6. Pulldown assays and immunoprecipitation-AC assays revealed that the complex formation of AC6, Snapin, and Snap25 is dependent on AC6-N and the phosphorylation of Snapin. The overexpression of Snap25 completely reversed the action of AC6. Collectively, in addition to cAMP production, AC6 plays a complex role in modulating neurite outgrowth by redistributing localization of the SNARE apparatus via its interaction with Snapin.
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Grasselli G, Mandolesi G, Strata P, Cesare P. Impaired sprouting and axonal atrophy in cerebellar climbing fibres following in vivo silencing of the growth-associated protein GAP-43. PLoS One 2011; 6:e20791. [PMID: 21695168 PMCID: PMC3112224 DOI: 10.1371/journal.pone.0020791] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2011] [Accepted: 05/09/2011] [Indexed: 01/19/2023] Open
Abstract
The adult mammalian central nervous system has a limited ability to establish new connections and to recover from traumatic or degenerative events. The olivo-cerebellar network represents an excellent model to investigate neuroprotection and repair in the brain during adulthood, due to its high plasticity and ordered synaptic organization. To shed light on the molecular mechanisms involved in these events, we focused on the growth-associated protein GAP-43 (also known as B-50 or neuromodulin). During development, this protein plays a crucial role in growth and in branch formation of neurites, while in the adult it is only expressed in a few brain regions, including the inferior olive (IO) where climbing fibres (CFs) originate. Following axotomy GAP-43 is usually up-regulated in association with regeneration. Here we describe an in vivo lentiviral-mediated gene silencing approach, used for the first time in the olivo-cerebellar system, to efficiently and specifically downregulate GAP-43 in rodents CFs. We show that lack of GAP-43 causes an atrophy of the CF in non-traumatic conditions, consisting in a decrease of its length, branching and number of synaptic boutons. We also investigated CF regenerative ability by inducing a subtotal lesion of the IO. Noteworthy, surviving CFs lacking GAP-43 were largely unable to sprout on surrounding Purkinje cells. Collectively, our results demonstrate that GAP-43 is essential both to maintain CFs structure in non-traumatic condition and to promote sprouting after partial lesion of the IO.
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Grumelli C, Corradini I, Matteoli M, Verderio C. Intrinsic calcium dynamics control botulinum toxin A susceptibility in distinct neuronal populations. Cell Calcium 2010; 47:419-24. [DOI: 10.1016/j.ceca.2010.03.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2010] [Revised: 02/23/2010] [Accepted: 03/01/2010] [Indexed: 11/25/2022]
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