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Basso V, Döbrössy MD, Thompson LH, Kirik D, Fuller HR, Gates MA. State of the Art in Sub-Phenotyping Midbrain Dopamine Neurons. BIOLOGY 2024; 13:690. [PMID: 39336117 PMCID: PMC11428604 DOI: 10.3390/biology13090690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2024] [Revised: 08/27/2024] [Accepted: 08/29/2024] [Indexed: 09/30/2024]
Abstract
Dopaminergic neurons in the ventral tegmental area (VTA) and the substantia nigra pars compacta (SNpc) comprise around 75% of all dopaminergic neurons in the human brain. While both groups of dopaminergic neurons are in close proximity in the midbrain and partially overlap, development, function, and impairments in these two classes of neurons are highly diverse. The molecular and cellular mechanisms underlying these differences are not yet fully understood, but research over the past decade has highlighted the need to differentiate between these two classes of dopaminergic neurons during their development and in the mature brain. This differentiation is crucial not only for understanding fundamental circuitry formation in the brain but also for developing therapies targeted to specific dopaminergic neuron classes without affecting others. In this review, we summarize the state of the art in our understanding of the differences between the dopaminergic neurons of the VTA and the SNpc, such as anatomy, structure, morphology, output and input, electrophysiology, development, and disorders, and discuss the current technologies and methods available for studying these two classes of dopaminergic neurons, highlighting their advantages, limitations, and the necessary improvements required to achieve more-precise therapeutic interventions.
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Affiliation(s)
- Valentina Basso
- School of Medicine, Keele University, Staffordshire ST5 5BG, UK
| | - Máté D Döbrössy
- Laboratory of Stereotaxy and Interventional Neurosciences, Department of Stereotactic and Functional, Neurosurgery, Medical Center, University of Freiburg, 79106 Freiburg im Breisgau, Germany
- Department of Stereotactic and Functional Neurosurgery, Medical Center, University of Freiburg, 79106 Freiburg im Breisgau, Germany
- Faculty of Biology, University of Freiburg, 79104 Freiburg im Breisgau, Germany
| | - Lachlan H Thompson
- Charles Perkins Centre, Faculty of Medicine and Health, School of Medical Sciences, The University of Sydney, Sydney, NSW 2006, Australia
- Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA
| | - Deniz Kirik
- Brain Repair and Imaging in Neural Systems (B.R.A.I.N.S) Unit, Department of Experimental Medical Science, Lund University, BMC D11, 22184 Lund, Sweden
| | - Heidi R Fuller
- School of Pharmacy and Bioengineering, Keele University, Staffordshire ST5 5BG, UK
- Wolfson Centre for Inherited Neuromuscular Disease, TORCH Building, RJAH Orthopaedic Hospital, Oswestry SY10 7AG, UK
| | - Monte A Gates
- School of Medicine, Keele University, Staffordshire ST5 5BG, UK
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2
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Vaglietti S, Villeri V, Dell’Oca M, Marchetti C, Cesano F, Rizzo F, Miller D, LaPierre L, Pelassa I, Monje FJ, Colnaghi L, Ghirardi M, Fiumara F. PolyQ length-based molecular encoding of vocalization frequency in FOXP2. iScience 2023; 26:108036. [PMID: 37860754 PMCID: PMC10582585 DOI: 10.1016/j.isci.2023.108036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 07/18/2023] [Accepted: 09/21/2023] [Indexed: 10/21/2023] Open
Abstract
The transcription factor FOXP2, a regulator of vocalization- and speech/language-related phenotypes, contains two long polyQ repeats (Q1 and Q2) displaying marked, still enigmatic length variation across mammals. We found that the Q1/Q2 length ratio quantitatively encodes vocalization frequency ranges, from the infrasonic to the ultrasonic, displaying striking convergent evolution patterns. Thus, species emitting ultrasonic vocalizations converge with bats in having a low ratio, whereas species vocalizing in the low-frequency/infrasonic range converge with elephants and whales, which have higher ratios. Similar, taxon-specific patterns were observed for the FOXP2-related protein FOXP1. At the molecular level, we observed that the FOXP2 polyQ tracts form coiled coils, assembling into condensates and fibrils, and drive liquid-liquid phase separation (LLPS). By integrating evolutionary and molecular analyses, we found that polyQ length variation related to vocalization frequency impacts FOXP2 structure, LLPS, and transcriptional activity, thus defining a novel form of polyQ length-based molecular encoding of vocalization frequency.
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Affiliation(s)
- Serena Vaglietti
- Rita Levi Montalcini Department of Neuroscience, University of Turin, 10125 Turin, Italy
| | - Veronica Villeri
- Rita Levi Montalcini Department of Neuroscience, University of Turin, 10125 Turin, Italy
| | - Marco Dell’Oca
- Rita Levi Montalcini Department of Neuroscience, University of Turin, 10125 Turin, Italy
| | - Chiara Marchetti
- Rita Levi Montalcini Department of Neuroscience, University of Turin, 10125 Turin, Italy
| | - Federico Cesano
- Department of Chemistry, University of Turin, 10125 Turin, Italy
| | - Francesca Rizzo
- Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon Tong, Hong Kong SAR 518057, China
| | - Dave Miller
- Cascades Pika Watch, Oregon Zoo, Portland, OR 97221, USA
| | - Louis LaPierre
- Deptartment of Natural Science, Lower Columbia College, Longview, WA 98632, USA
| | - Ilaria Pelassa
- Rita Levi Montalcini Department of Neuroscience, University of Turin, 10125 Turin, Italy
| | - Francisco J. Monje
- Department of Neurophysiology and Neuropharmacology, Medical University of Vienna, 1090 Vienna, Austria
| | - Luca Colnaghi
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, 20132 Milan, Italy
- School of Medicine, Vita-Salute San Raffaele University, 20132 Milan, Italy
| | - Mirella Ghirardi
- Rita Levi Montalcini Department of Neuroscience, University of Turin, 10125 Turin, Italy
| | - Ferdinando Fiumara
- Rita Levi Montalcini Department of Neuroscience, University of Turin, 10125 Turin, Italy
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Bustos Plonka F, Sosa LJ, Quiroga S. Sec3 exocyst component knockdown inhibits axonal formation and cortical neuronal migration during brain cortex development. J Neurochem 2021; 160:203-217. [PMID: 34862972 DOI: 10.1111/jnc.15554] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 10/27/2021] [Accepted: 11/25/2021] [Indexed: 12/22/2022]
Abstract
Neurons are the largest known cells, with complex and highly polarized morphologies and consist of a cell body (soma), several dendrites, and a single axon. The establishment of polarity necessitates initial axonal outgrowth in concomitance with the addition of new membrane to the axon's plasmalemma. Axolemmal expansion occurs by exocytosis of plasmalemmal precursor vesicles primarily at the neuronal growth cone membrane. The multiprotein exocyst complex drives spatial location and specificity of vesicle fusion at plasma membrane. However, the specific participation of its different proteins on neuronal differentiation has not been fully established. In the present work we analyzed the role of Sec3, a prominent exocyst complex protein on neuronal differentiation. Using mice hippocampal primary cultures, we determined that Sec3 is expressed in neurons at early stages prior to neuronal polarization. Furthermore, we determined that silencing of Sec3 in mice hippocampal neurons in culture precluded polarization. Moreover, using in utero electroporation experiments, we determined that Sec3 knockdown affected cortical neurons migration and morphology during neocortex formation. Our results demonstrate that the exocyst complex protein Sec3 plays an important role in axon formation in neuronal differentiation and the migration of neuronal progenitors during cortex development.
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Affiliation(s)
- Florentyna Bustos Plonka
- Facultad de Ciencias Químicas, Departamento de Química Biológica Ranwel Caputto, Universidad Nacional de Córdoba y CIQUIBIC-CONICET, Córdoba, Argentina
| | - Lucas J Sosa
- Facultad de Ciencias Químicas, Departamento de Química Biológica Ranwel Caputto, Universidad Nacional de Córdoba y CIQUIBIC-CONICET, Córdoba, Argentina
| | - Santiago Quiroga
- Facultad de Ciencias Químicas, Departamento de Química Biológica Ranwel Caputto, Universidad Nacional de Córdoba y CIQUIBIC-CONICET, Córdoba, Argentina
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4
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Calleja-Felipe M, Wojtas MN, Diaz-González M, Ciceri D, Escribano R, Ouro A, Morales M, Knafo S. FORTIS: a live-cell assay to monitor AMPA receptors using pH-sensitive fluorescence tags. Transl Psychiatry 2021; 11:324. [PMID: 34045447 PMCID: PMC8160262 DOI: 10.1038/s41398-021-01457-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 05/09/2021] [Accepted: 05/18/2021] [Indexed: 11/26/2022] Open
Abstract
The real-time live fluorescent monitoring of surface AMPA receptors (AMPARs) could open new opportunities for drug discovery and phenotypic screening concerning neuropsychiatric disorders. We have developed FORTIS, a tool based on pH sensitivity capable of detecting subtle changes in surface AMPARs at a neuronal population level. The expression of SEP-GluA1 or pHuji-GluA1 recombinant AMPAR subunits in mammalian neurons cultured in 96-well plates enables surface AMPARs to be monitored with a microplate reader. Thus, FORTIS can register rapid changes in surface AMPARs induced by drugs or genetic modifications without having to rely on conventional electrophysiology or imaging. By combining FORTIS with pharmacological manipulations, basal surface AMPARs, and plasticity-like changes can be monitored. We expect that employing FORTIS to screen for changes in surface AMPARs will accelerate both neuroscience research and drug discovery.
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Affiliation(s)
- María Calleja-Felipe
- Department of Physiology and Cell Biology, Faculty of Health Sciences, The National Institute for Biotechnology in the Negev, and The Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer-Sheva, Israel
- Instituto Biofisika (UPV/EHU, CSIC), University of the Basque Country, Leioa, E-48940, Spain
| | - Magdalena Natalia Wojtas
- Department of Physiology and Cell Biology, Faculty of Health Sciences, The National Institute for Biotechnology in the Negev, and The Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Marta Diaz-González
- Department of Physiology and Cell Biology, Faculty of Health Sciences, The National Institute for Biotechnology in the Negev, and The Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Dalila Ciceri
- Instituto Biofisika (UPV/EHU, CSIC), University of the Basque Country, Leioa, E-48940, Spain
| | - Raúl Escribano
- Fundación Biofísica Bizkaia/Biofisika Bizkaia Fundazioa (FBB), Barrio Sarriena s/n, Leioa, E-48940, Spain
| | - Alberto Ouro
- Department of Physiology and Cell Biology, Faculty of Health Sciences, The National Institute for Biotechnology in the Negev, and The Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Miguel Morales
- Instituto Biofisika (UPV/EHU, CSIC), University of the Basque Country, Leioa, E-48940, Spain
| | - Shira Knafo
- Department of Physiology and Cell Biology, Faculty of Health Sciences, The National Institute for Biotechnology in the Negev, and The Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
- Instituto Biofisika (UPV/EHU, CSIC), University of the Basque Country, Leioa, E-48940, Spain.
- Ikerbasque, Basque Foundation for Science, Bilbao, 48013, Spain.
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5
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Bartko JC, Li Y, Sun G, Halterman MW. Phosphorylation within the bipartite NLS alters the localization and toxicity of the ER stress response factor DDIT3/CHOP. Cell Signal 2020; 74:109713. [PMID: 32673756 DOI: 10.1016/j.cellsig.2020.109713] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 07/06/2020] [Accepted: 07/09/2020] [Indexed: 02/04/2023]
Abstract
Regulated nuclear-cytoplasmic trafficking is a well-established mechanism utilized by cells to regulate adaptive and maladaptive responses to acute oxidant stress. Commonly associated with endoplasmic reticulum stress, the bZIP transcription factor CCAAT/enhancer-binding protein homologous protein (CHOP/DDIT3) mediates the cellular response to redox stress with effects on cellular growth, differentiation, and survival. We show through functional analyses that CHOP contains a conserved, compound pat4/bipartite nuclear localization signal within the basic DNA-binding domain. Using phylogenetic analyses and mass spectrometry, we now show that Ser107 located within the linker region of the bipartite NLS domain is a substrate for phosphorylation under standard culture conditions. Studies using the S107E phospho-mimic of CHOP indicate that changes in the charge properties at this residue regulate CHOP's nuclear-to-cytoplasmic ratio. And while co-stimulation with the SERCA inhibitor thapsigargin induced injury in cells expressing wild-type CHOP, the S107A point-mutant blocked this response. These findings indicate that phosphorylation within the bipartite NLS exerts regulatory effects on both the subcellular localization and toxic potential of DDIT3/CHOP. Future studies geared towards defining the relevant kinase/phosphatase networks that converge on the phosphorylation-regulated NLS (prNLS) phosphoepitope may provide an opportunity to constrain cellular damage in the context of acute ER stress.
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Affiliation(s)
- Jonathan C Bartko
- Departments of Pathology and Laboratory Medicine, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, United States
| | - Yinghui Li
- Department of Neurology, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, United States
| | - George Sun
- Department of Neurology, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, United States
| | - Marc W Halterman
- Department of Neurology, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, United States; Department of Neuroscience, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, United States.
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6
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Zhang N, Chin JS, Chew SY. Localised non-viral delivery of nucleic acids for nerve regeneration in injured nervous systems. Exp Neurol 2018; 319:112820. [PMID: 30195695 DOI: 10.1016/j.expneurol.2018.09.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Revised: 08/31/2018] [Accepted: 09/05/2018] [Indexed: 02/07/2023]
Abstract
Axons damaged by traumatic injuries are often unable to spontaneously regenerate in the adult central nervous system (CNS). Although the peripheral nervous system (PNS) has some regenerative capacity, its ability to regrow remains limited across large lesion gaps due to scar tissue formation. Nucleic acid therapy holds the potential of improving regeneration by enhancing the intrinsic growth ability of neurons and overcoming the inhibitory environment that prevents neurite outgrowth. Nucleic acids modulate gene expression by over-expression of neuronal growth factor or silencing growth-inhibitory molecules. Although in vitro outcomes appear promising, the lack of efficient non-viral nucleic acid delivery methods to the nervous system has limited the application of nucleic acid therapeutics to patients. Here, we review the recent development of efficient non-viral nucleic acid delivery platforms, as applied to the nervous system, including the transfection vectors and carriers used, as well as matrices and scaffolds that are currently used. Additionally, we will discuss possible improvements for localised nucleic acid delivery.
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Affiliation(s)
- Na Zhang
- School of Chemical and Biomedical Engineering, Nanyang Technological University, 637459, Singapore
| | - Jiah Shin Chin
- School of Chemical and Biomedical Engineering, Nanyang Technological University, 637459, Singapore; NTU Institute of Health Technologies, Interdisciplinary Graduate School, Nanyang Technological University, 639798, Singapore
| | - Sing Yian Chew
- School of Chemical and Biomedical Engineering, Nanyang Technological University, 637459, Singapore; Lee Kong Chian School of Medicine, Nanyang Technological University, 308232, Singapore.
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7
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Lopes FM, Bristot IJ, da Motta LL, Parsons RB, Klamt F. Mimicking Parkinson's Disease in a Dish: Merits and Pitfalls of the Most Commonly used Dopaminergic In Vitro Models. Neuromolecular Med 2017; 19:241-255. [PMID: 28721669 DOI: 10.1007/s12017-017-8454-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Accepted: 07/12/2017] [Indexed: 12/27/2022]
Abstract
Parkinson's disease (PD) is the second most common neurodegenerative disorder and has both unknown etiology and non-curative therapeutic options. Patients begin to present the classic motor symptoms of PD-tremor at rest, bradykinesia and rigidity-once 50-70% of the dopaminergic neurons of the nigrostriatal pathway have degenerated. As a consequence of this, it is difficult to investigate the early-stage events of disease pathogenesis. In vitro experimental models are used extensively in PD research because they present a controlled environment that enables the direct investigation of the early molecular mechanisms that are potentially involved with dopaminergic degeneration, as well as for the screening of potential therapeutic drugs. However, the establishment of PD in vitro models is a controversial issue for neuroscience research not only because it is challenging to mimic, in isolated cell systems, the physiological neuronal environment, but also the pathophysiological conditions experienced by human dopaminergic cells in vivo during the progression of the disease. Since no previous work has attempted to systematically review the literature regarding the establishment of an optimal in vitro model, and/or the features presented by available models used in the PD field, this review aims to summarize the merits and limitations of the most widely used dopaminergic in vitro models in PD research, which may help the PD researcher to choose the most appropriate model for studies directed at the elucidation of the early-stage molecular events underlying PD onset and progression.
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Affiliation(s)
- Fernanda Martins Lopes
- Laboratório de Bioquímica Celular, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul (UFRGS), Rua Ramiro Barcelos, 2600, Porto Alegre, RS, 90035-003, Brazil. .,Institute of Pharmaceutical Science, King's College London, 150 Stamford Street, London, SE1 9NH, UK.
| | - Ivi Juliana Bristot
- Laboratório de Bioquímica Celular, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul (UFRGS), Rua Ramiro Barcelos, 2600, Porto Alegre, RS, 90035-003, Brazil
| | - Leonardo Lisbôa da Motta
- Laboratório de Bioquímica Celular, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul (UFRGS), Rua Ramiro Barcelos, 2600, Porto Alegre, RS, 90035-003, Brazil
| | - Richard B Parsons
- Institute of Pharmaceutical Science, King's College London, 150 Stamford Street, London, SE1 9NH, UK
| | - Fabio Klamt
- Laboratório de Bioquímica Celular, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul (UFRGS), Rua Ramiro Barcelos, 2600, Porto Alegre, RS, 90035-003, Brazil.
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8
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Grassi D, Plonka FB, Oksdath M, Guil AN, Sosa LJ, Quiroga S. Selected SNARE proteins are essential for the polarized membrane insertion of igf-1 receptor and the regulation of initial axonal outgrowth in neurons. Cell Discov 2015; 1:15023. [PMID: 27462422 PMCID: PMC4860833 DOI: 10.1038/celldisc.2015.23] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Accepted: 07/07/2015] [Indexed: 02/08/2023] Open
Abstract
The establishment of polarity necessitates initial axonal outgrowth and,
therefore, the addition of new membrane to the axon’s plasmalemma.
Axolemmal expansion occurs by exocytosis of plasmalemmal precursor vesicles
(PPVs) primarily at the neuronal growth cone. Little is known about the SNAREs
family proteins involved in the regulation of PPV fusion with the neuronal
plasmalemma at early stages of differentiation. We show here that five SNARE
proteins (VAMP2, VAMP4, VAMP7, Syntaxin6 and SNAP23) were expressed by
hippocampal pyramidal neurons before polarization. Expression silencing of three
of these proteins (VAMP4, Syntaxin6 and SNAP23) repressed axonal outgrowth and
the establishment of neuronal polarity, by inhibiting IGF-1 receptor exocytotic
polarized insertion, necessary for neuronal polarization. In addition,
stimulation with IGF-1 triggered the association of VAMP4, Syntaxin6 and SNAP23
to vesicular structures carrying the IGF-1 receptor and overexpression of a
negative dominant form of Syntaxin6 significantly inhibited exocytosis of IGF-1
receptor containing vesicles at the neuronal growth cone. Taken together, our
results indicated that VAMP4, Syntaxin6 and SNAP23 functions are essential for
regulation of PPV exocytosis and the polarized insertion of IGF-1 receptor and,
therefore, required for initial axonal elongation and the establishment of
neuronal polarity.
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Affiliation(s)
- Diego Grassi
- Departamento de Química Biológica-CIQUIBIC, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba-CONICET , Córdoba, Argentina
| | - Florentyna Bustos Plonka
- Departamento de Química Biológica-CIQUIBIC, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba-CONICET , Córdoba, Argentina
| | - Mariana Oksdath
- Departamento de Química Biológica-CIQUIBIC, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba-CONICET , Córdoba, Argentina
| | - Alvaro Nieto Guil
- Departamento de Química Biológica-CIQUIBIC, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba-CONICET , Córdoba, Argentina
| | - Lucas J Sosa
- Departamento de Química Biológica-CIQUIBIC, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba-CONICET , Córdoba, Argentina
| | - Santiago Quiroga
- Departamento de Química Biológica-CIQUIBIC, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba-CONICET , Córdoba, Argentina
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9
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Pulido-Salgado M, Vidal-Taboada JM, Saura J. C/EBPβ and C/EBPδ transcription factors: Basic biology and roles in the CNS. Prog Neurobiol 2015; 132:1-33. [PMID: 26143335 DOI: 10.1016/j.pneurobio.2015.06.003] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Revised: 05/08/2015] [Accepted: 06/16/2015] [Indexed: 02/01/2023]
Abstract
CCAAT/enhancer binding protein (C/EBP) β and C/EBPδ are transcription factors of the basic-leucine zipper class which share phylogenetic, structural and functional features. In this review we first describe in depth their basic molecular biology which includes fascinating aspects such as the regulated use of alternative initiation codons in the C/EBPβ mRNA. The physical interactions with multiple transcription factors which greatly opens the number of potentially regulated genes or the presence of at least five different types of post-translational modifications are also remarkable molecular mechanisms that modulate C/EBPβ and C/EBPδ function. In the second part, we review the present knowledge on the localization, expression changes and physiological roles of C/EBPβ and C/EBPδ in neurons, astrocytes and microglia. We conclude that C/EBPβ and C/EBPδ share two unique features related to their role in the CNS: whereas in neurons they participate in memory formation and synaptic plasticity, in glial cells they regulate the pro-inflammatory program. Because of their role in neuroinflammation, C/EBPβ and C/EBPδ in microglia are potential targets for treatment of neurodegenerative disorders. Any strategy to reduce C/EBPβ and C/EBPδ activity in neuroinflammation needs to take into account its potential side-effects in neurons. Therefore, cell-specific treatments will be required for the successful application of this strategy.
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Affiliation(s)
- Marta Pulido-Salgado
- Biochemistry and Molecular Biology Unit, School of Medicine, University of Barcelona, IDIBAPS, Casanova 143, planta 3, 08036 Barcelona, Spain
| | - Jose M Vidal-Taboada
- Biochemistry and Molecular Biology Unit, School of Medicine, University of Barcelona, IDIBAPS, Casanova 143, planta 3, 08036 Barcelona, Spain
| | - Josep Saura
- Biochemistry and Molecular Biology Unit, School of Medicine, University of Barcelona, IDIBAPS, Casanova 143, planta 3, 08036 Barcelona, Spain.
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10
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Zhao XS, Fu WY, Hung KW, Chien WWY, Li Z, Fu AK, Ip NY. NRC-interacting factor directs neurite outgrowth in an activity-dependent manner. Neuroscience 2015; 289:207-13. [PMID: 25573434 DOI: 10.1016/j.neuroscience.2014.12.041] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2014] [Revised: 12/05/2014] [Accepted: 12/24/2014] [Indexed: 11/18/2022]
Abstract
Nuclear hormone receptor coregulator-interacting factor 1 (NIF-1) is a zinc finger nuclear protein that was initially identified to enhance nuclear hormone receptor transcription via its interaction with nuclear hormone receptor coregulator (NRC). NIF-1 may regulate gene transcription either by modulating general transcriptional machinery or remodeling chromatin structure through interactions with specific protein partners. We previously reported that the cytoplasmic/nuclear localization of NIF-1 is regulated by the neuronal Cdk5 activator p35, suggesting potential neuronal functions for NIF-1. The present study reveals that NIF-1 plays critical roles in regulating neuronal morphogenesis at early stages. NIF-1 was prominently expressed in the nuclei of developing rat cortical neurons. Knockdown of NIF-1 expression attenuated both neurite outgrowth in cultured cortical neurons and retinoic acid (RA)-treated Neuro-2a neuroblastoma cells. Furthermore, activity-induced Ca(2+) influx, which is critical for neuronal morphogenesis, stimulated the nuclear localization of NIF-1 in cortical neurons. Suppression of NIF-1 expression reduced the up-regulation of neuronal activity-dependent gene transcription. These findings collectively suggest that NIF-1 directs neuronal morphogenesis during early developmental stages through modulating activity-dependent gene transcription.
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Affiliation(s)
- X-S Zhao
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - W-Y Fu
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - K-W Hung
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - W W Y Chien
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - Z Li
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - A K Fu
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - N Y Ip
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
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11
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Aoshima Y, Hokama R, Sou K, Sarker SR, Iida K, Nakamura H, Inoue T, Takeoka S. Cationic amino acid based lipids as effective nonviral gene delivery vectors for primary cultured neurons. ACS Chem Neurosci 2013; 4:1514-9. [PMID: 24087930 PMCID: PMC3867963 DOI: 10.1021/cn400036j] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The delivery of specific genes into neurons offers a potent approach for treatment of diseases as well as for the study of neuronal cell biology. Here we investigated the capabilities of cationic amino acid based lipid assemblies to act as nonviral gene delivery vectors in primary cultured neurons. An arginine-based lipid, Arg-C3-Glu2C14, and a lysine-based lipid, Lys-C3-Glu2C14, with two different types of counterion, chloride ion (Cl-) and trifluoroacetic acid (TFA-), were shown to successfully mediate transfection of primary cultured neurons with plasmid DNA encoding green fluorescent protein. Among four types of lipids, we optimized their conditions such as the lipid-to-DNA ratio and the amount of pDNA and conducted a cytotoxicity assay at the same time. Overall, Arg-C3-Glu2C14 with TFA- induced a rate of transfection in primary cultured neurons higher than that of Lys-C3-Glu2C14 using an optimal weight ratio of lipid-to-plasmid DNA of 1. Moreover, it was suggested that Arg-C3-Glu2C14 with TFA- showed the optimized value higher than that of Lipofectamine2000 in experimental conditions. Thus, Arg-C3-Glu2C14 with TFA- is a promising candidate as a reliable transfection reagent for primary cultured neurons with a relatively low cytotoxicity.
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Affiliation(s)
- Yumiko Aoshima
- Department of Life Science
and Medical Bioscience, Graduate School of
Advanced Science and Engineering, Waseda
University (TWIns), 2-2 Wakamatsu-cho,
Shinjuku-ku, Tokyo 162-8480, Japan
| | - Ryosuke Hokama
- Department of Life Science
and Medical Bioscience, Graduate School of
Advanced Science and Engineering, Waseda
University (TWIns), 2-2 Wakamatsu-cho,
Shinjuku-ku, Tokyo 162-8480, Japan
| | - Keitaro Sou
- Department of Life Science
and Medical Bioscience, Graduate School of
Advanced Science and Engineering, Waseda
University (TWIns), 2-2 Wakamatsu-cho,
Shinjuku-ku, Tokyo 162-8480, Japan
| | - Satya Ranjan Sarker
- Department of Life Science
and Medical Bioscience, Graduate School of
Advanced Science and Engineering, Waseda
University (TWIns), 2-2 Wakamatsu-cho,
Shinjuku-ku, Tokyo 162-8480, Japan
| | - Kabuto Iida
- Department of Life Science
and Medical Bioscience, Graduate School of
Advanced Science and Engineering, Waseda
University (TWIns), 2-2 Wakamatsu-cho,
Shinjuku-ku, Tokyo 162-8480, Japan
| | - Hideki Nakamura
- Department of Life Science
and Medical Bioscience, Graduate School of
Advanced Science and Engineering, Waseda
University (TWIns), 2-2 Wakamatsu-cho,
Shinjuku-ku, Tokyo 162-8480, Japan
| | - Takafumi Inoue
- Department of Life Science
and Medical Bioscience, Graduate School of
Advanced Science and Engineering, Waseda
University (TWIns), 2-2 Wakamatsu-cho,
Shinjuku-ku, Tokyo 162-8480, Japan
| | - Shinji Takeoka
- Department of Life Science
and Medical Bioscience, Graduate School of
Advanced Science and Engineering, Waseda
University (TWIns), 2-2 Wakamatsu-cho,
Shinjuku-ku, Tokyo 162-8480, Japan
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12
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Zhang L, Hu C, Fan Y, Wu Y. Binary gene vectors based on hyperbranched poly(l-lactide-co-polyglycerol) and polyethylenimine for prolonged transgene expression via co-assembly with DNA into fiber core-shell triplexes. J Mater Chem B 2013; 1:6271-6282. [PMID: 32261700 DOI: 10.1039/c3tb21150a] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Hyper-branched PG6-PLA polymers based on hydrophilic hyperbranched polyglycerol (PG6) and the ester chain poly(l-lactide) (PLA) were synthesized and facilitated to develop a novel biocompatible release-controlled gene vector. The hyper-branched structure of PG6-PLA was verified by NMR, FT-IR and SEC-MALLS analysis. The co-assembly of PG6-PLA with high molecular weight polyethylenimine (PEI) of 25 kDa was discussed. The results of TEM, fluorescence tracking and size/zeta-potential analysis revealed that the PG6-PLA/PEI25k/DNA could co-assemble to generate a novel fiber core-shell conformation. In vitro cell experiment demonstrated that PG6-PLA significantly enhanced the ability of PEI25k to remain within cells and mediate luciferase and EGFP expression in the human embryonic kidney cell line 293T and human cervical carcinoma cell line HeLa, which was accompanied by improved cell biocompatibility and an extended period of transgene expression. Importantly, the binary vector PG6-PLA/PEI25k exhibited specific affinity to some tumour cell lines including HeLa and the HepG2 human hepatoma cell line. These results suggested that the novel gene delivery system based on fiber core-shell PG6-PLA/PEI25k/DNA can serve as a gene delivery system to mediate more efficient transgene expression.
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Affiliation(s)
- Lei Zhang
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, PR China.
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13
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Tahara K, Moriuchi T, Tsukui M, Hirota A, Maeno T, Toriyama M, Inagaki N, Kikuchi JI. Ceramic Coating of Liposomal Gene Carrier for Minimizing Toxicity to Primary Hippocampal Neurons. CHEM LETT 2013. [DOI: 10.1246/cl.130541] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Keishiro Tahara
- Graduate School of Materials Science, Nara Institute of Science and Technology
| | - Takanobu Moriuchi
- Graduate School of Materials Science, Nara Institute of Science and Technology
| | - Miku Tsukui
- Graduate School of Materials Science, Nara Institute of Science and Technology
| | - Akira Hirota
- Graduate School of Materials Science, Nara Institute of Science and Technology
| | - Takanori Maeno
- Graduate School of Biological Sciences, Nara Institute of Science and Technology
| | - Michinori Toriyama
- Graduate School of Biological Sciences, Nara Institute of Science and Technology
| | - Naoyuki Inagaki
- Graduate School of Biological Sciences, Nara Institute of Science and Technology
| | - Jun-ichi Kikuchi
- Graduate School of Materials Science, Nara Institute of Science and Technology
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14
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Zhao Y, Chen F, Chen S, Liu X, Cui M, Dong Q. The Parkinson's disease-associated gene PINK1
protects neurons from ischemic damage by decreasing mitochondrial translocation of the fission promoter Drp1. J Neurochem 2013; 127:711-22. [PMID: 23772688 DOI: 10.1111/jnc.12340] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2013] [Revised: 06/12/2013] [Accepted: 06/12/2013] [Indexed: 01/28/2023]
Affiliation(s)
- Yanxin Zhao
- Department of Neurology; The 10th People's Hospital; Tongji University; Shanghai China
| | - Fangzhe Chen
- Department of Neurology; Huashan hospital; State Key Laboratory of Medical Neurobiology; Fudan University; Shanghai China
| | - Shufen Chen
- Department of Neurology; Huashan hospital; State Key Laboratory of Medical Neurobiology; Fudan University; Shanghai China
| | - Xueyuan Liu
- Department of Neurology; The 10th People's Hospital; Tongji University; Shanghai China
| | - Mei Cui
- Department of Neurology; Huashan hospital; State Key Laboratory of Medical Neurobiology; Fudan University; Shanghai China
| | - Qiang Dong
- Department of Neurology; Huashan hospital; State Key Laboratory of Medical Neurobiology; Fudan University; Shanghai China
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15
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Cui X, Chopp M, Shehadah A, Zacharek A, Kuzmin-Nichols N, Sanberg CD, Dai J, Zhang C, Ueno Y, Roberts C, Chen J. Therapeutic benefit of treatment of stroke with simvastatin and human umbilical cord blood cells: neurogenesis, synaptic plasticity, and axon growth. Cell Transplant 2012; 21:845-56. [PMID: 22405262 DOI: 10.3727/096368911x627417] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The therapeutic efficacy of cell-based therapy after stroke can be enhanced by making the host brain tissue more receptive to the administered cells, which thereby facilitates brain plasticity. We hypothesized that simvastatin increases human umbilical cord blood cell (HUCBC) migration into the ischemic brain and promotes brain plasticity and neurological functional outcome after stroke. Rats were subjected to 2-h middle cerebral artery occlusion (MCAo) and administered subtherapeutic doses of simvastatin (0.5 mg/kg, gavaged daily for 7 days), HUCBCs (1 × 10(6), one time injection via tail vein), or combination simvastatin with HUCBCs starting at 24 h after stroke. Combination treatment of stroke showed an interactive effect in improvement of neurological outcome compared with simvastatin or HUCBC monotherapy groups. In addition, combination treatment significantly increased brain-derived neurotrophic factor/TrkB expression and the number of engrafted HUCBCs in the ischemic brain compared with HUCBC monotherapy. The number of engrafted HUCBCs was significantly correlated with functional outcome (modified neurological severity score). Combination treatment significantly increased neurogenesis and synaptic plasticity in the ischemic brain, and promoted neuroblast migration in cultured subventricular zone explants. Using primary cultured neurons (PCNs), we found that combination treatment enhanced neurite outgrowth compared with nontreatment control, simvastatin or HUCBC supernatant monotherapy. Inhibition of TrkB significantly attenuated combination treatment-induced neurite outgrowth. Our data indicate that combination simvastatin and HUCBC treatment of stroke increases BDNF/TrkB expression, enhances HUCBC migration into the ischemic brain, amplifies endogenous neurogenesis, synaptic plasticity and axonal growth, and thereby improves functional outcome after stroke.
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Affiliation(s)
- Xu Cui
- Department of Neurology, Henry Ford Hospital, Detroit, MI 48202, USA
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16
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Cui X, Chopp M, Zacharek A, Roberts C, Buller B, Ion M, Chen J. Niacin treatment of stroke increases synaptic plasticity and axon growth in rats. Stroke 2010; 41:2044-9. [PMID: 20671245 DOI: 10.1161/strokeaha.110.589333] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
BACKGROUND AND PURPOSE Niacin is the most effective medication in current clinical use for increasing high-density lipoprotein cholesterol. We tested the hypothesis that niacin treatment of stroke promotes synaptic plasticity and axon growth in the ischemic brain. METHODS Male Wistar rats were subjected to 2 hours of middle cerebral artery occlusion and treated with or without Niaspan (a prolonged-release formulation of niacin, 40 mg/kg) daily for 14 days starting 24 hours after middle cerebral artery occlusion. The expression of synaptophysin, Nogo receptor, Bielschowsky silver, brain-derived neurotrophic factor, and its receptor tropomyosin-related kinase B were measured by immunohistostaining and Western blot, respectively, in the ischemic brain. Complementing in vivo studies, primary cultured neurons were used to test the effect of niacin and high-density lipoprotein on neurite outgrowth and brain-derived neurotrophic factor/tropomyosin-related kinase B expression. RESULTS Niaspan treatment of stroke significantly increased synaptophysin, Bielschowsky silver, brain-derived neurotrophic factor/tropomyosin-related kinase B expression, and decreased Nogo receptor expression in the ischemic brain compared with middle cerebral artery occlusion control animals (P<0.05, n=8/group). Niacin and high-density lipoprotein treatment significantly increased neurite outgrowth and brain-derived neurotrophic factor/tropomyosin-related kinase B expression in primary cultured neurons. Tropomyosin-related kinase B inhibitor attenuated niacin-induced neurite outgrowth (P<0.05, n=6/group). CONCLUSIONS Niacin treatment of stroke promotes synaptic plasticity and axon growth, which is mediated, at least partially, by the brain-derived neurotrophic factor/tropomyosin-related kinase B pathways.
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Affiliation(s)
- Xu Cui
- Department of Neurology, Henry Ford Hospital, Detroit, Mich 48202, USA
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17
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Cui M, Tang X, Christian WV, Yoon Y, Tieu K. Perturbations in mitochondrial dynamics induced by human mutant PINK1 can be rescued by the mitochondrial division inhibitor mdivi-1. J Biol Chem 2010; 285:11740-52. [PMID: 20164189 DOI: 10.1074/jbc.m109.066662] [Citation(s) in RCA: 159] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Mutations in the mitochondrial encoded protein PTEN-induced putative kinase 1 (PINK1) cause autosomal recessive Parkinson disease (PD). In mammalian cells, mutant PINK1 has been reported to promote fission or inhibit fusion in mitochondria; however, the mechanism by which this process occurs remains elusive. Using an ecdysone-inducible expression system in mammalian dopaminergic neuronal cells, we report here that human mutant PINK1 (L347P and W437X) mediates an overall fission effect by increasing the ratio of mitochondrial fission over fusion proteins, leading to excessive dysfunctional fragmented mitochondria. Knocking down endogenous Pink1 produces similar effects. In contrast, overexpressing human wild type PINK1 produces a pro-fusion effect by increasing the ratio of mitochondrial fusion/fission proteins without resulting in functionally compromised mitochondria. Parkin knockdown blocks the imbalance in fission/fusion proteins. Furthermore, overexpressing parkin and ubiquitin increases degradation of the mitochondrial fission hFis1 protein, suggesting PINK1 and parkin maintain proper mitochondrial function and integrity via the fission/fusion machinery. Through genetic manipulations and treatment with the small molecule mitochondrial division inhibitor (mdivi-1), which inhibits DLP1/Drp1, both structural and functional mitochondrial defects induced by mutant PINK1 were attenuated, highlighting a potential novel therapeutic avenue for Parkinson disease.
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Affiliation(s)
- Mei Cui
- Department of Neurology, University of Rochester School of Medicine, Rochester, New York 14642, USA
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18
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Daub A, Sharma P, Finkbeiner S. High-content screening of primary neurons: ready for prime time. Curr Opin Neurobiol 2009; 19:537-43. [PMID: 19889533 DOI: 10.1016/j.conb.2009.10.002] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2009] [Accepted: 10/01/2009] [Indexed: 12/14/2022]
Abstract
High-content screening (HCS), historically limited to drug-development companies, is now a powerful and affordable technology for academic researchers. Through automated routines, this technology acquires large datasets of fluorescence images depicting the functional states of thousands to millions of cells. Information on shapes, textures, intensities, and localizations is then used to create unique representations, or 'phenotypic signatures,' of each cell. These signatures quantify physiologic or diseased states, for example, dendritic arborization, drug response, or cell coping strategies. Live-cell imaging in HCS adds the ability to correlate cellular events at different points in time, thereby allowing sensitivities and observations not possible with fixed endpoint analysis. HCS with live-cell imaging therefore provides an unprecedented capability to detect spatiotemporal changes in cells and is particularly suited for time-dependent, stochastic processes such as neurodegenerative disorders.
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Affiliation(s)
- Aaron Daub
- Gladstone Institute of Neurological Disease, San Francisco, CA 94158, United States
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19
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Ray B, Bailey JA, Sarkar S, Lahiri DK. Molecular and immunocytochemical characterization of primary neuronal cultures from adult rat brain: Differential expression of neuronal and glial protein markers. J Neurosci Methods 2009; 184:294-302. [PMID: 19720084 DOI: 10.1016/j.jneumeth.2009.08.018] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2009] [Revised: 08/12/2009] [Accepted: 08/22/2009] [Indexed: 11/30/2022]
Abstract
Neurobiological studies using primary neuronal cultures commonly employ fetal-derived neurons, but much less often adult brain-derived neurons. Our goal is to perform morphological and molecular characterization of primary neuronal cultures from adult rat brain, including the relative expression of neuronal and glial cell markers at different time points. We tested the hypothesis that long-term neuronal viability is compatible with glial proliferation in adult neuron culture. We examined neuron culture from adult rat brain, which was maintained at steady state up to 24 days, and characterized them on the basis of cellular, molecular and biochemical properties at different time points of the culture. We identified neuronal and glial cells by both immunocytochemical and western immunoblotting techniques using NSE and Tau as neuronal markers and GFAP as glial protein marker, which revealed the presence of predominantly neuronal cells in the initial phase of the culture and a rise in glial cells from day 12 onwards. Notably, neuronal cells were preserved in the culture along with the glial cells even at day 24. Transfection of the cultured cells with a GFP expression vector and plasmids containing a luciferase reporter gene under the control of two different gene promoters demonstrated DNA transfectability. Taken together, these results suggest a differential expression of neuronal and glial cells at different time points and long-term neuronal viability in the presence of glial proliferation. Such adult neurons serve as a suitable system for the application of neurodegeneration models and for drug target discovery in various brain disorders including Alzheimer's disease.
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Affiliation(s)
- Balmiki Ray
- Department of Psychiatry, Institute of Psychiatric Research, Indiana University School of Medicine, 791 Union Drive, Indianapolis, IN 46202, USA
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20
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Li Y, Lim S, Hoffman D, Aspenstrom P, Federoff HJ, Rempe DA. HUMMR, a hypoxia- and HIF-1alpha-inducible protein, alters mitochondrial distribution and transport. ACTA ACUST UNITED AC 2009; 185:1065-81. [PMID: 19528298 PMCID: PMC2711615 DOI: 10.1083/jcb.200811033] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Mitochondrial transport is critical for maintenance of normal neuronal function. Here, we identify a novel mitochondria protein, hypoxia up-regulated mitochondrial movement regulator (HUMMR), which is expressed in neurons and is markedly induced by hypoxia-inducible factor 1 α (HIF-1α). Interestingly, HUMMR interacts with Miro-1 and Miro-2, mitochondrial proteins that are critical for mediating mitochondrial transport. Interestingly, knockdown of HUMMR or HIF-1 function in neurons exposed to hypoxia markedly reduces mitochondrial content in axons. Because mitochondrial transport and distribution are inextricably linked, the impact of reduced HUMMR function on the direction of mitochondrial transport was also explored. Loss of HUMMR function in hypoxia diminished the percentage of motile mitochondria moving in the anterograde direction and enhanced the percentage moving in the retrograde direction. Thus, HUMMR, a novel mitochondrial protein induced by HIF-1 and hypoxia, biases mitochondria transport in the anterograde direction. These findings have broad implications for maintenance of neuronal viability and function during physiological and pathological states.
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Affiliation(s)
- Yan Li
- Department of Neurology, Center for Neural Development and Disease, University of Rochester School of Medicine & Dentistry, Rochester, NY 14642, USA
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