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Padmanabhan D, Naksuk N, Killu AK, Kapa S, Witt C, Sugrue A, DeSimone CV, Madhavan M, Groot JR, O'Brien B, Rabbette T, Coffey K, Asirvatham SJ. Electroporation of epicardial autonomic ganglia: Safety and efficacy in medium‐term canine models. J Cardiovasc Electrophysiol 2019; 30:607-615. [DOI: 10.1111/jce.13860] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 01/19/2019] [Accepted: 01/19/2019] [Indexed: 11/27/2022]
Affiliation(s)
- Deepak Padmanabhan
- Department of Cardiovascular MedicineAcademic Medical CenterAmsterdam The Netherlands
| | - Niyada Naksuk
- Department of Cardiovascular MedicineAcademic Medical CenterAmsterdam The Netherlands
| | - Ammar K. Killu
- Department of Cardiovascular MedicineAcademic Medical CenterAmsterdam The Netherlands
| | - Suraj Kapa
- Department of Cardiovascular MedicineAcademic Medical CenterAmsterdam The Netherlands
| | - Chance Witt
- Department of Cardiovascular MedicineAcademic Medical CenterAmsterdam The Netherlands
| | - Alan Sugrue
- Department of Cardiovascular MedicineAcademic Medical CenterAmsterdam The Netherlands
| | | | - Malini Madhavan
- Department of Cardiovascular MedicineAcademic Medical CenterAmsterdam The Netherlands
| | - J. R. Groot
- Heart Center, Department of Cardiology, Academic Medical CenterAmsterdam The Netherlands
| | - Barry O'Brien
- Biomedical engineering, National University of IrelandGalway Ireland
| | - Tadhg Rabbette
- Biomedical engineering, National University of IrelandGalway Ireland
| | - Kenneth Coffey
- Biomedical engineering, National University of IrelandGalway Ireland
| | - Samuel J. Asirvatham
- Division of Pediatric CardiologyAcademic Medical CenterAmsterdam The Netherlands
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Jin L, Lange W, Kempmann A, Maybeck V, Günther A, Gruteser N, Baumann A, Offenhäusser A. High-efficiency transduction and specific expression of ChR2opt for optogenetic manipulation of primary cortical neurons mediated by recombinant adeno-associated viruses. J Biotechnol 2016; 233:171-80. [DOI: 10.1016/j.jbiotec.2016.07.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Revised: 06/29/2016] [Accepted: 07/01/2016] [Indexed: 10/21/2022]
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Vergara MN, Gutierrez C, Canto-Soler MV. Efficient Gene Transfer in Chick Retinas for Primary Cell Culture Studies: An Ex-ovo Electroporation Approach. J Vis Exp 2015:e52002. [PMID: 26556302 DOI: 10.3791/52002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
The cone photoreceptor-enriched cultures derived from embryonic chick retinas have become an indispensable tool for researchers around the world studying the biology of retinal neurons, particularly photoreceptors. The applications of this system go beyond basic research, as they can easily be adapted to high throughput technologies for drug development. However, genetic manipulation of retinal photoreceptors in these cultures has proven to be very challenging, posing an important limitation to the usefulness of the system. We have recently developed and validated an ex ovo plasmid electroporation technique that increases the rate of transfection of retinal cells in these cultures by five-fold compared to other currently available protocols(1). In this method embryonic chick eyes are enucleated at stage 27, the RPE is removed, and the retinal cup is placed in a plasmid-containing solution and electroporated using easily constructed custom-made electrodes. The retinas are then dissociated and cultured using standard procedures. This technique can be applied to overexpression studies as well as to the downregulation of gene expression, for example via the use of plasmid-driven RNAi technology, commonly achieving transgene expression in 25% of the photoreceptor population. The video format of the present publication will make this technology easily accessible to researchers in the field, enabling the study of gene function in primary retinal cultures. We have also included detailed explanations of the critical steps of this procedure for a successful outcome and reproducibility.
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Affiliation(s)
- M Natalia Vergara
- Wilmer Eye Institute, The Johns Hopkins University School of Medicine
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Yu L, Reynaud F, Falk J, Spencer A, Ding YD, Baumlé V, Lu R, Castellani V, Yuan C, Rudkin BB. Highly efficient method for gene delivery into mouse dorsal root ganglia neurons. Front Mol Neurosci 2015; 8:2. [PMID: 25698920 PMCID: PMC4313362 DOI: 10.3389/fnmol.2015.00002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Accepted: 01/06/2015] [Indexed: 01/21/2023] Open
Abstract
The development of gene transfection technologies has greatly advanced our understanding of life sciences. While use of viral vectors has clear efficacy, it requires specific expertise and biological containment conditions. Electroporation has become an effective and commonly used method for introducing DNA into neurons and in intact brain tissue. The present study describes the use of the Neon® electroporation system to transfect genes into dorsal root ganglia neurons isolated from embryonic mouse Day 13.5–16. This cell type has been particularly recalcitrant and refractory to physical or chemical methods for introduction of DNA. By optimizing the culture condition and parameters including voltage and duration for this specific electroporation system, high efficiency (60–80%) and low toxicity (>60% survival) were achieved with robust differentiation in response to Nerve growth factor (NGF). Moreover, 3–50 times fewer cells are needed (6 × 104) compared with other traditional electroporation methods. This approach underlines the efficacy of this type of electroporation, particularly when only limited amount of cells can be obtained, and is expected to greatly facilitate the study of gene function in dorsal root ganglia neuron cultures.
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Affiliation(s)
- Lingli Yu
- Differentiation and Cell Cycle Group, Laboratoire de Biologie Moléculaire de la Cellule, UMR 5239, Centre National de la Recherche Scientifique, Ecole normale Supérieure de Lyon, University of Lyon 1 Claude Bernard, University of Lyon Lyon, France ; Laboratory of Molecular and Cellular Neurophysiology, East China Normal University Shanghai, China ; Joint Laboratory of Neuropathogenesis, Key Laboratory of Brain Functional Genomics, Chinese Ministry of Education, East China Normal University, Centre National de la Recherche Scientifique, Ecole Normale Supérieure de Lyon Shanghai, China
| | - Florie Reynaud
- Centre de Génétique et Physiologie Moléculaire et Cellulaire, UMR Centre National de la Recherche Scientifique 5534, University of Lyon 1 Claude Bernard, University of Lyon Villeurbanne, France
| | - Julien Falk
- Centre de Génétique et Physiologie Moléculaire et Cellulaire, UMR Centre National de la Recherche Scientifique 5534, University of Lyon 1 Claude Bernard, University of Lyon Villeurbanne, France
| | - Ambre Spencer
- Differentiation and Cell Cycle Group, Laboratoire de Biologie Moléculaire de la Cellule, UMR 5239, Centre National de la Recherche Scientifique, Ecole normale Supérieure de Lyon, University of Lyon 1 Claude Bernard, University of Lyon Lyon, France ; Laboratory of Molecular and Cellular Neurophysiology, East China Normal University Shanghai, China ; Joint Laboratory of Neuropathogenesis, Key Laboratory of Brain Functional Genomics, Chinese Ministry of Education, East China Normal University, Centre National de la Recherche Scientifique, Ecole Normale Supérieure de Lyon Shanghai, China
| | - Yin-Di Ding
- Differentiation and Cell Cycle Group, Laboratoire de Biologie Moléculaire de la Cellule, UMR 5239, Centre National de la Recherche Scientifique, Ecole normale Supérieure de Lyon, University of Lyon 1 Claude Bernard, University of Lyon Lyon, France ; Laboratory of Molecular and Cellular Neurophysiology, East China Normal University Shanghai, China ; Joint Laboratory of Neuropathogenesis, Key Laboratory of Brain Functional Genomics, Chinese Ministry of Education, East China Normal University, Centre National de la Recherche Scientifique, Ecole Normale Supérieure de Lyon Shanghai, China
| | - Véronique Baumlé
- Differentiation and Cell Cycle Group, Laboratoire de Biologie Moléculaire de la Cellule, UMR 5239, Centre National de la Recherche Scientifique, Ecole normale Supérieure de Lyon, University of Lyon 1 Claude Bernard, University of Lyon Lyon, France ; Joint Laboratory of Neuropathogenesis, Key Laboratory of Brain Functional Genomics, Chinese Ministry of Education, East China Normal University, Centre National de la Recherche Scientifique, Ecole Normale Supérieure de Lyon Shanghai, China
| | - Ruisheng Lu
- Laboratory of Molecular and Cellular Neurophysiology, East China Normal University Shanghai, China ; Joint Laboratory of Neuropathogenesis, Key Laboratory of Brain Functional Genomics, Chinese Ministry of Education, East China Normal University, Centre National de la Recherche Scientifique, Ecole Normale Supérieure de Lyon Shanghai, China
| | - Valérie Castellani
- Centre de Génétique et Physiologie Moléculaire et Cellulaire, UMR Centre National de la Recherche Scientifique 5534, University of Lyon 1 Claude Bernard, University of Lyon Villeurbanne, France
| | - Chonggang Yuan
- Differentiation and Cell Cycle Group, Laboratoire de Biologie Moléculaire de la Cellule, UMR 5239, Centre National de la Recherche Scientifique, Ecole normale Supérieure de Lyon, University of Lyon 1 Claude Bernard, University of Lyon Lyon, France ; Joint Laboratory of Neuropathogenesis, Key Laboratory of Brain Functional Genomics, Chinese Ministry of Education, East China Normal University, Centre National de la Recherche Scientifique, Ecole Normale Supérieure de Lyon Shanghai, China
| | - Brian B Rudkin
- Laboratory of Molecular and Cellular Neurophysiology, East China Normal University Shanghai, China ; Joint Laboratory of Neuropathogenesis, Key Laboratory of Brain Functional Genomics, Chinese Ministry of Education, East China Normal University, Centre National de la Recherche Scientifique, Ecole Normale Supérieure de Lyon Shanghai, China
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Kulesa PM, McKinney MC, McLennan R. Developmental imaging: the avian embryo hatches to the challenge. ACTA ACUST UNITED AC 2014; 99:121-33. [PMID: 23897596 DOI: 10.1002/bdrc.21036] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2013] [Accepted: 05/31/2013] [Indexed: 01/27/2023]
Abstract
The avian embryo provides a multifaceted model to study developmental mechanisms because of its accessibility to microsurgery, fluorescence cell labeling, in vivo imaging, and molecular manipulation. Early two-dimensional planar growth of the avian embryo mimics human development and provides unique access to complex cell migration patterns using light microscopy. Later developmental events continue to permit access to both light and other imaging modalities, making the avian embryo an excellent model for developmental imaging. For example, significant insights into cell and tissue behaviors within the primitive streak, craniofacial region, and cardiovascular and peripheral nervous systems have come from avian embryo studies. In this review, we provide an update to recent advances in embryo and tissue slice culture and imaging, fluorescence cell labeling, and gene profiling. We focus on how technical advances in the chick and quail provide a clearer understanding of how embryonic cell dynamics are beautifully choreographed in space and time to sculpt cells into functioning structures. We summarize how these technical advances help us to better understand basic developmental mechanisms that may lead to clinical research into human birth defects and tissue repair.
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Affiliation(s)
- Paul M Kulesa
- Stowers Institute for Medical Research, Kansas City, MO 64110, USA.
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Li F, Yamaguchi K, Okada K, Matsushita K, Enatsu N, Chiba K, Yue H, Fujisawa M. Efficient Transfection of DNA into Primarily Cultured Rat Sertoli Cells by Electroporation1. Biol Reprod 2013; 88:61. [DOI: 10.1095/biolreprod.112.106260] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
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Ex vivo electroporation of retinal cells: a novel, high efficiency method for functional studies in primary retinal cultures. Exp Eye Res 2013; 109:40-50. [PMID: 23370269 DOI: 10.1016/j.exer.2013.01.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2012] [Revised: 12/17/2012] [Accepted: 01/19/2013] [Indexed: 11/22/2022]
Abstract
Primary retinal cultures constitute valuable tools not only for basic research on retinal cell development and physiology, but also for the identification of factors or drugs that promote cell survival and differentiation. In order to take full advantage of the benefits of this system it is imperative to develop efficient and reliable techniques for the manipulation of gene expression. However, achieving appropriate transfection efficiencies in these cultures has remained challenging. The purpose of this work was to develop and optimize a technique that would allow the transfection of chick retinal cells with high efficiency and reproducibility for multiple applications. We developed an ex vivo electroporation method applied to dissociated retinal cell cultures that offers a significant improvement over other currently available transfection techniques, increasing efficiency by five-fold. In this method, eyes were enucleated, devoid of RPE, and electroporated with GFP-encoding plasmids using custom-made electrodes. Electroporated retinas were then dissociated into single cells and plated in low density conditions, to be analyzed after 4 days of incubation. Parameters such as voltage and number of electric pulses, as well as plasmid concentration and developmental stage of the animal were optimized for efficiency. The characteristics of the cultures were assessed by morphology and immunocytochemistry, and cell viability was determined by ethidium homodimer staining. Cell imaging and counting was performed using an automated high-throughput system. This procedure resulted in transfection efficiencies in the order of 22-25% of cultured cells, encompassing both photoreceptors and non-photoreceptor neurons, and without affecting normal cell survival and differentiation. Finally, the feasibility of the technique for cell-autonomous studies of gene function in a biologically relevant context was tested by carrying out gain and loss-of-function experiments for the transcription factor PAX6. Electroporation of a plasmid construct expressing PAX6 resulted in a marked upregulation in the expression levels of this protein that could be measured in the whole culture as well as cell-intrinsically. This was accompanied by a significant decrease in the percentage of cells differentiating as photoreceptors among the transfected population. Conversely, electroporation of an RNAi construct targeting PAX6 resulted in a significant decrease in the levels of this protein, with a concomitant increase in the proportion of photoreceptors. Taken together these results provide strong proof-of-principle of the suitability of this technique for genetic studies in retinal cultures. The combination of the high transfection efficiency obtained by this method with automated high-throughput cell analysis supplies the scientific community with a powerful system for performing functional studies in a cell-autonomous manner.
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Satkauskas S, Ruzgys P, Venslauskas MS. Towards the mechanisms for efficient gene transfer into cells and tissues by means of cell electroporation. Expert Opin Biol Ther 2012; 12:275-86. [PMID: 22339479 DOI: 10.1517/14712598.2012.654775] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
INTRODUCTION Intracellular gene electrotransfer by means of electroporation has been on the increase during the past decade. Significant progress has been achieved both in characterizing mechanisms of gene electrotransfer and in optimizing the protocol in many preclinical trials. Recently this has led to initiation of clinical trials of gene electrotransfer to treat metastatic melanomas. Further progress with the method in various clinical trials requires better understanding of mechanisms of gene electrotransfer. AREAS COVERED A summary of recent progress in understanding mechanisms of gene electrotransfer, imparting general knowledge of cell electroporation and intracellular molecule electrotransfer. EXPERT OPINION Gene electrotransfer into cells and tissues is a complex process involving multiple steps that lead to plasmid DNA passage from the extracellular region to the cell nucleus crossing the barriers of the plasma membrane, cytoplasm and nucleus membrane. Electrical parameters of pulses used for gene electrotransfer affect the initial steps of DNA translocation through the plasma membrane and play a crucial role in determining the transfection efficiency. When considering gene electrotransfer into tissues it becomes clear that other nonelectrical conditions are also of primary importance.
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Affiliation(s)
- Saulius Satkauskas
- Vytautas Magnus University, Biology Department, Biophysical Research Group, Vileikos 8, Kaunas LT-44404, Lithuania.
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Mthunzi P, Dholakia K, Gunn-Moore F. Phototransfection of mammalian cells using femtosecond laser pulses: optimization and applicability to stem cell differentiation. JOURNAL OF BIOMEDICAL OPTICS 2010; 15:041507. [PMID: 20799785 DOI: 10.1117/1.3430733] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Recently, femtosecond laser pulses have been utilized for the targeted introduction of genetic matter into mammalian cells. This rapidly expanding and developing novel optical technique using a tightly focused laser light beam is called phototransfection. Extending previous studies [Stevenson et al., Opt. Express 14, 7125-7133 (2006)], we show that femtosecond lasers can be used to phototransfect a range of different cell lines, and specifically that this novel technology can also transfect mouse embryonic stem cell colonies with approximately 25% efficiency. Notably, we show the ability of differentiating these cells into the extraembryonic endoderm using phototransfection. Furthermore, we present two new findings aimed at optimizing the phototransfection method and improving applicability: first, the influence of the cell passage number on the transfection efficiency is explored and, second, the ability to enhance the transfection efficiency via whole culture treatments. Our results should encourage wider uptake of this methodology.
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Affiliation(s)
- Patience Mthunzi
- University of St. Andrews, School of Physics and Astronomy, North Haugh, St. Andrews, Fife, Scotland, United Kingdom
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Amiri M, Hollenbeck PJ. Mitochondrial biogenesis in the axons of vertebrate peripheral neurons. Dev Neurobiol 2009; 68:1348-61. [PMID: 18666204 DOI: 10.1002/dneu.20668] [Citation(s) in RCA: 114] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Mitochondria are widely distributed via regulated transport in neurons, but their sites of biogenesis remain uncertain. Most mitochondrial proteins are encoded in the nuclear genome, and evidence has suggested that mitochondrial DNA (mtDNA) replication occurs mainly or entirely in the cell body. However, it has also become clear that nuclear-encoded mitochondrial proteins can be translated in the axon and that components of the mitochondrial replication machinery reside there as well. We assessed directly whether mtDNA replication can occur in the axons of chick peripheral neurons labeled with 5-bromo-2'-deoxyuridine (BrdU). In axons that were physically separated from the cell body or had disrupted organelle transport between the cell bodies and axons, a significant fraction of mtDNA synthesis continued. We also detected the mitochondrial fission protein Drp1 in neurons by immunofluorescence or expression of GFP-Drp1. Its presence and distribution on the majority of axonal mitochondria indicated that a substantial number had undergone recent division in the axon. Because the morphology of mitochondria is maintained by the balance of fission and fusion events, we either inhibited Drp1 expression by RNAi or overexpressed the fusion protein Mfn1. Both methods resulted in significantly longer mitochondria in axons, including many at a great distance from the cell body. These data indicate that mitochondria can replicate their DNA, divide, and fuse locally within the axon; thus, the biogenesis of mitochondria is not limited to the cell body.
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Affiliation(s)
- Mandana Amiri
- Department of Biological Sciences, Purdue University, West Lafayette, Indiana 47906, USA
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Van Raay TJ, Lassiter RT, Stark MR. Electroporation strategies for genetic manipulation and cell labeling. Methods Mol Biol 2008; 438:305-317. [PMID: 18369766 DOI: 10.1007/978-1-59745-133-8_23] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Electroporation has emerged as an effective method for cell labeling and manipulation of gene expression. In the past decade, electroporation applications have expanded to include in vivo chick, mouse, Xenopus, and zebrafish techniques, along with numerous in vitro strategies for cell and tissue culture. We focus on applications relevant to neural stem cell research, providing detailed protocols for in ovo chick electroporation and in vitro targeting of neuroepithelial precursor cells. Electroporation descriptions and related figures identify the tools and reagents needed to carry out targeting of the neuroepithelium. Various applications of the electroporation technique in neural stem cell research are highlighted, along with corresponding publications.
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Affiliation(s)
- Terence J Van Raay
- Department of Biological Sciences, Vanderbilt University, Nashville, TN, USA
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Tropism and toxicity of adeno-associated viral vector serotypes 1, 2, 5, 6, 7, 8, and 9 in rat neurons and glia in vitro. Virology 2007; 372:24-34. [PMID: 18035387 DOI: 10.1016/j.virol.2007.10.007] [Citation(s) in RCA: 113] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2007] [Revised: 08/01/2007] [Accepted: 10/05/2007] [Indexed: 12/19/2022]
Abstract
Recombinant adeno-associated viral (rAAV) vectors are frequently used for gene delivery to the central nervous system and are capable of transducing neurons and glia in vitro. In this study, seven serotypes of a rAAV vector expressing green fluorescent protein (GFP) were characterized for tropism and toxicity in primary cortical cells derived from embryonic rat brain. At 2 days after transduction, serotypes 1 and 5 through 8 expressed GFP predominately in glia, but by 6 days post-transduction expression was neuronal except for AAV5. AAV2 and 9 produced minimal GFP expression. Using cell viability assays, toxicity was observed at higher multiplicities of infection (MOI) for all serotypes except AAV2 and 9. The toxicity of AAV1 and 5-8 affected mostly glia as indicated by a loss of glial-marker immunoreactivity. A frameshift mutation in the GFP gene reduced overall toxicity for serotypes 1, 5 and 6, but not 7 and 8 suggesting that the toxicity was not solely due to the overexpression of GFP. Collectively, a differential tropism and toxicity was observed among the AAV serotypes on primary cortical cultures with an overall preferential glial transduction and toxicity.
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Falk J, Drinjakovic J, Leung KM, Dwivedy A, Regan AG, Piper M, Holt CE. Electroporation of cDNA/Morpholinos to targeted areas of embryonic CNS in Xenopus. BMC DEVELOPMENTAL BIOLOGY 2007; 7:107. [PMID: 17900342 PMCID: PMC2147031 DOI: 10.1186/1471-213x-7-107] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/08/2007] [Accepted: 09/27/2007] [Indexed: 02/07/2023]
Abstract
Background Blastomere injection of mRNA or antisense oligonucleotides has proven effective in analyzing early gene function in Xenopus. However, functional analysis of genes involved in neuronal differentiation and axon pathfinding by this method is often hampered by earlier function of these genes during development. Therefore, fine spatio-temporal control of over-expression or knock-down approaches is required to specifically address the role of a given gene in these processes. Results We describe here an electroporation procedure that can be used with high efficiency and low toxicity for targeting DNA and antisense morpholino oligonucleotides (MOs) into spatially restricted regions of the Xenopus CNS at a critical time-window of development (22–50 hour post-fertilization) when axonal tracts are first forming. The approach relies on the design of "electroporation chambers" that enable reproducible positioning of fixed-spaced electrodes coupled with accurate DNA/MO injection. Simple adjustments can be made to the electroporation chamber to suit the shape of different aged embryos and to alter the size and location of the targeted region. This procedure can be used to electroporate separate regions of the CNS in the same embryo allowing separate manipulation of growing axons and their intermediate and final targets in the brain. Conclusion Our study demonstrates that electroporation can be used as a versatile tool to investigate molecular pathways involved in axon extension during Xenopus embryogenesis. Electroporation enables gain or loss of function studies to be performed with easy monitoring of electroporated cells. Double-targeted transfection provides a unique opportunity to monitor axon-target interaction in vivo. Finally, electroporated embryos represent a valuable source of MO-loaded or DNA transfected cells for in vitro analysis. The technique has broad applications as it can be tailored easily to other developing organ systems and to other organisms by making simple adjustments to the electroporation chamber.
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Affiliation(s)
- Julien Falk
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3DY, UK
| | - Jovana Drinjakovic
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3DY, UK
| | - Kin Mei Leung
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3DY, UK
| | - Asha Dwivedy
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3DY, UK
| | - Aoife G Regan
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3DY, UK
| | - Michael Piper
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3DY, UK
- The Queensland Brain Institute, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Christine E Holt
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3DY, UK
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Tretyakova I, Zolotukhin AS, Tan W, Bear J, Propst F, Ruthel G, Felber BK. Nuclear Export Factor Family Protein Participates in Cytoplasmic mRNA Trafficking. J Biol Chem 2005; 280:31981-90. [PMID: 16014633 DOI: 10.1074/jbc.m502736200] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In eukaryotes, the nuclear export of mRNA is mediated by nuclear export factor 1 (NXF1) receptors. Metazoans encode additional NXF1-related proteins of unknown function, which share homology and domain organization with NXF1. Some mammalian NXF1-related genes are expressed preferentially in the brain and are thought to participate in neuronal mRNA metabolism. To address the roles of NXF1-related factors, we studied the two mouse NXF1 homologues, mNXF2 and mNXF7. In neuronal cells, mNXF2, but not mNXF7, exhibited mRNA export activity similar to that of Tip-associated protein/NXF1. Surprisingly, mNXF7 incorporated into mobile particles in the neurites that contained poly(A) and ribosomal RNA and colocalized with Staufen1-containing transport granules, indicating a role in neuronal mRNA trafficking. Yeast two-hybrid interaction, coimmunoprecipitation, and in vitro binding studies showed that NXF proteins bound to brain-specific microtubule-associated proteins (MAP) such as MAP1B and the WD repeat protein Unrip. Both in vitro and in vivo, MAP1B also bound to NXF export cofactor U2AF as well as to Staufen1 and Unrip. These findings revealed a network of interactions likely coupling the export and cytoplasmic trafficking of mRNA. We propose a model in which MAP1B tethers the NXF-associated mRNA to microtubules and facilitates their translocation along dendrites while Unrip provides a scaffold for the assembly of these transport intermediates.
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Affiliation(s)
- Irina Tretyakova
- Human Retrovirus Pathogenesis Section, Vaccine Branch, Center for Cancer Research, NCI-Frederick, National Institutes of Health, Frederick, Maryland 21702, USA
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Abstract
The study of embryonic events using different animal model systems is crucial for gaining insights into human development and birth defects. Biological imaging plays a major role in this effort by providing a spatiotemporal framework to link complex cell movements with molecular data. However, depending on the age of the embryo and the location of a morphogenetic event, visualization often requires the design of novel culture and imaging techniques. One of the primary model systems for biological imaging is the avian embryo, due to its accessibility to manipulation, relatively two-dimensional morphogenesis early on, and viability when grown in culture. Significant work in avian embryo culture and cell labeling, together with advances in imaging technology, now make it possible to monitor many developmental events within the period from egg laying to hatching. Here, we present the latest in avian developmental imaging, focusing on cell labeling, embryo culture, and imaging technologies.
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Affiliation(s)
- Paul M Kulesa
- Stowers Institute for Medical Research, Kansas City, Missouri 64110, USA.
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Abstract
The chicken embryo has served as a classic model system for developmental studies due to its easy access for surgical manipulations and a wealth of data about chicken embryogenesis. Notably, the mechanisms controlling limb development have been explored best in the chick. Recently, the method of in ovo electroporation has been used successfully to transfect particular cells/tissues during embryonic development, without the production or infectivity associated with retroviruses. With the sequencing of the chicken genome near completion, this approach will provide a powerful opportunity to examine the function of chicken genes and their counterparts in other species. In ovo electroporation has been most effectively used to date for ectopic or overexpression analyses. However, recent studies indicate that this approach can be used successfully for loss-of-function analyses, including protein knockdown experiments with morpholinos and RNAi. Here, I will discuss parameters for using in ovo electroporation successfully to study developmental processes.
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Affiliation(s)
- Catherine E Krull
- Biological Sciences, University of Missouri-Columbia, Columbia, Missouri 65211, USA.
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