1
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Ubba V, Joseph S, Awe O, Jones D, Dsilva MK, Feng M, Wang J, Fu X, Akbar RJ, Bodnar BH, Hu W, Wang H, Yang X, Yang L, Yang P, Taib B, Ahima R, Divall S, Wu S. Reproductive Profile of Neuronal Androgen Receptor Knockout Female Mice With a Low Dose of DHT. Endocrinology 2024; 165:bqad199. [PMID: 38156784 PMCID: PMC10794876 DOI: 10.1210/endocr/bqad199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 09/08/2023] [Accepted: 12/29/2023] [Indexed: 01/03/2024]
Abstract
Hyperandrogenism and polycystic ovarian syndrome result from the imbalance or increase of androgen levels in females. Androgen receptor (AR) mediates the effects of androgens, and this study examines whether neuronal AR plays a role in reproduction under normal and increased androgen conditions in female mice. The neuron-specific AR knockout (KO) mouse (SynARKO) was generated from a female mouse (synapsin promoter driven Cre) and a male mouse (Ar fl/y). Puberty onset and the levels of reproductive hormones such as LH, FSH, testosterone, and estradiol were comparable between the control and the SynARKO mice. There were no differences in cyclicity and fertility between the control and SynARKO mice, with similar impairment in both groups on DHT treatment. Neuronal AR KO, as in this SynARKO mouse model, did not alleviate the infertility associated with DHT treatment. These studies suggest that neuronal AR KO neither altered reproductive function under physiological androgen levels, nor restored fertility under hyperandrogenic conditions.
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Affiliation(s)
- Vaibhave Ubba
- Center for Metabolic Disease Research, Temple University School of Medicine, Philadelphia, PA, 19140, USA
| | - Serene Joseph
- Center for Metabolic Disease Research, Temple University School of Medicine, Philadelphia, PA, 19140, USA
| | - Olubusayo Awe
- Department of Cellular and Molecular Physiology, Johns Hopkins University School of Medicine, Baltimore, MD, 21287, USA
| | - Dustin Jones
- Department of Cellular and Molecular Physiology, Johns Hopkins University School of Medicine, Baltimore, MD, 21287, USA
| | - Milan K Dsilva
- Center for Metabolic Disease Research, Temple University School of Medicine, Philadelphia, PA, 19140, USA
| | - Mingxiao Feng
- Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD, 21087, USA
| | - Junjiang Wang
- Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD, 21087, USA
- Departments of Gastrointestinal Surgery and General Surgery, Guangdong Provincial People’s Hospital, Southern Medical University, Guangzhou, 510080, China
| | - Xiaomin Fu
- Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD, 21087, USA
- Department of Endocrinology, The First Medical Center, Chinese PLA General Hospital, Beijing, 100853, China
| | - Razeen J Akbar
- Center for Metabolic Disease Research, Temple University School of Medicine, Philadelphia, PA, 19140, USA
| | - Brittany H Bodnar
- Center for Metabolic Disease Research, Temple University School of Medicine, Philadelphia, PA, 19140, USA
| | - Wenhui Hu
- Center for Metabolic Disease Research, Temple University School of Medicine, Philadelphia, PA, 19140, USA
| | - Hong Wang
- Center for Metabolic Disease Research, Temple University School of Medicine, Philadelphia, PA, 19140, USA
| | - Xiaofeng Yang
- Center for Metabolic Disease Research, Temple University School of Medicine, Philadelphia, PA, 19140, USA
| | - Ling Yang
- Department of Medical Genetics & Molecular Biochemistry, Temple University School of Medicine, Philadelphia, PA, 19140, USA
| | - Peixin Yang
- Department of Obstetrics, Gynecology and Reproductive Sciences, University of Maryland School of Medicine, Baltimore, 21201, USA
| | - Bouchra Taib
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, 21287, USA
| | - Rexford Ahima
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, 21287, USA
| | - Sara Divall
- Department of Pediatrics, University of Washington, Seattle’s Children’s Hospital, Seattle, WA, 98145-5005, USA
| | - Sheng Wu
- Center for Metabolic Disease Research, Temple University School of Medicine, Philadelphia, PA, 19140, USA
- Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD, 21087, USA
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2
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Baghdadi M, Mesaros A, Purrio M, Partridge L. Sex-specific effects of Cre expression in Syn1Cre mice. Sci Rep 2023; 13:10037. [PMID: 37340054 DOI: 10.1038/s41598-023-37029-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Accepted: 06/14/2023] [Indexed: 06/22/2023] Open
Abstract
The Cre-loxP system has been used to generate cell-type specific mutations in mice, allowing researchers to investigate the underlying biological mechanisms of disease. However, the Cre-recombinase alone can induce phenotypes that confound comparisons among genotypes if the appropriate Cre control is not included. In this study, we characterised behavioural, morphological and metabolic phenotypes of the pan-neuronal Syn1Cre line. We found that these mice possess intact neuromuscular parameters but have reduced exploratory activity and a male-specific increase in anxiety-like behaviour. Moreover, we observed a male-specific deficit in learning and long-term memory of Syn1Cre mice that could be a result of decreased visual acuity. Furthermore, we found that over-expression of human growth hormone (hGH) from Syn1Cre results in a male-specific reduction in body weight and femur length, potentially through decreased hepatic Igf1 expression. However, metabolic characteristics of Syn1Cre mice such as glucose metabolism, energy expenditure and feeding were unaffected by the presence of Syn1Cre. In conclusion, our data demonstrate that Syn1Cre expression has effects on behavioural and morphological traits. This finding highlights the importance of including the Cre control in all comparisons, while the male-specific effects on some phenotypes highlight the importance of including both sexes.
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Affiliation(s)
| | - Andrea Mesaros
- Max-Planck Institute for Biology of Ageing, Cologne, Germany
| | - Martin Purrio
- Max-Planck Institute for Biology of Ageing, Cologne, Germany
| | - Linda Partridge
- Max-Planck Institute for Biology of Ageing, Cologne, Germany.
- Institute of Healthy Ageing, and GEE, UCL, London, UK.
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3
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Ersing I, Rego M, Wang C, Zhang Y, DeMaio KH, Tillgren M, Fava A, Clouse G, Patrick M, Guerin K, Fan M. Quality control for Adeno-associated viral vector production. NEUROMETHODS 2023; 195:77-101. [PMID: 38585382 PMCID: PMC10997381 DOI: 10.1007/978-1-0716-2918-5_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
Adeno-associated viral vectors (AAV) are frequently used by neuroscientists to deliver tools, such as biosensors and optogenetic and chemogenetic actuators, in vivo. Despite its widespread use, AAV vector characterization and quality control can vary between labs and viral vector cores leading to variable results and irreproducibility. This protocol describes some of the characterization and quality control assays necessary to confirm an AAV vector's titer, genomic identity, serotype and purity.
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Affiliation(s)
- Ina Ersing
- Addgene, 490 Arsenal Way, Suite 100, Watertown, MA 02472, USA
| | - Meghan Rego
- Addgene, 490 Arsenal Way, Suite 100, Watertown, MA 02472, USA
| | - Chen Wang
- Addgene, 490 Arsenal Way, Suite 100, Watertown, MA 02472, USA
| | - Yijun Zhang
- Addgene, 490 Arsenal Way, Suite 100, Watertown, MA 02472, USA
| | | | | | - Alanna Fava
- Addgene, 490 Arsenal Way, Suite 100, Watertown, MA 02472, USA
| | | | | | - Karen Guerin
- Vedere Bio II, Inc, 300 Technology square, Cambridge, MA 02139, USA
| | - Melina Fan
- Addgene, 490 Arsenal Way, Suite 100, Watertown, MA 02472, USA
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4
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Kim YE, Kim S, Kim IH. Neural circuit-specific gene manipulation in mouse brain in vivo using split-intein-mediated split-Cre system. STAR Protoc 2022; 3:101807. [PMID: 36386891 PMCID: PMC9641071 DOI: 10.1016/j.xpro.2022.101807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Neural network studies require efficient genetic tools to analyze individual neural circuit functions in vivo. Thus, we developed an advanced circuit-selective gene manipulating tool utilizing anterograde and retrograde adeno-associated viruses (AAVs) encoding split-intein-mediated split-Cre. This strategy can be applied to visualize a specific neural circuit as well as manipulate multiple genes in the circuit neurons. Here, we describe the production and purification of the AAVs, viral injection to the mouse brain, and imaging analysis for a specific neural circuit. For complete details on the use and execution of this protocol, please refer to Kim et al. (2022).
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Affiliation(s)
- Yong-Eun Kim
- Department of Anatomy and Neurobiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA; Neuroscience Institute, University of Tennessee Health Science Center, Memphis, TN 38163, USA.
| | - Sunwhi Kim
- Department of Anatomy and Neurobiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA; Neuroscience Institute, University of Tennessee Health Science Center, Memphis, TN 38163, USA.
| | - Il Hwan Kim
- Department of Anatomy and Neurobiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA; Neuroscience Institute, University of Tennessee Health Science Center, Memphis, TN 38163, USA.
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5
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Paton KM, Selfridge J, Guy J, Bird A. Comparative analysis of potential broad-spectrum neuronal Cre drivers. Wellcome Open Res 2022; 7:185. [PMID: 35966957 PMCID: PMC9353198 DOI: 10.12688/wellcomeopenres.17965.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/01/2022] [Indexed: 11/20/2022] Open
Abstract
Cre/Lox technology is a powerful tool in the mouse genetics tool-box as it enables tissue-specific and inducible mutagenesis of specific gene loci. Correct interpretation of phenotypes depends upon knowledge of the Cre expression pattern in the chosen mouse driver line to ensure that appropriate cell types are targeted. For studies of the brain and neurological disease a pan-neuronal promoter that reliably drives efficient neuron-specific transgene expression would be valuable. Here we compare a widely used "pan-neuronal" mouse Cre driver line, Syn1-cre, with a little-known alternative, Snap25-IRES2-cre. Our results show that the Syn1-cre line broadly expresses in the brain but is indetectable in more than half of all neurons and weakly active in testes. In contrast the Snap25-IRES2-cre line expressed Cre in a high proportion of neurons (~85%) and was indetectable in all non-brain tissues that were analysed, including testes. Our findings suggest that for many purposes Snap25-IRES2-cre is superior to Syn1-cre as a potential pan-neuronal cre driver.
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Affiliation(s)
- Katie M Paton
- Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh, EH9 3BF, UK
| | - Jim Selfridge
- Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh, EH9 3BF, UK
| | - Jacky Guy
- Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh, EH9 3BF, UK
| | - Adrian Bird
- Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh, EH9 3BF, UK
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6
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Kreher C, Favret J, Weinstock NI, Maulik M, Hong X, Gelb MH, Wrabetz L, Feltri ML, Shin D. Neuron-specific ablation of the Krabbe disease gene galactosylceramidase in mice results in neurodegeneration. PLoS Biol 2022; 20:e3001661. [PMID: 35789331 PMCID: PMC9255775 DOI: 10.1371/journal.pbio.3001661] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 05/06/2022] [Indexed: 12/21/2022] Open
Abstract
Krabbe disease is caused by a deficiency of the lysosomal galactosylceramidase (GALC) enzyme, which results in the accumulation of galactosylceramide (GalCer) and psychosine. In Krabbe disease, the brunt of demyelination and neurodegeneration is believed to result from the dysfunction of myelinating glia. Recent studies have shown that neuronal axons are both structurally and functionally compromised in Krabbe disease, even before demyelination, suggesting a possible neuron-autonomous role of GALC. Using a novel neuron-specific Galc knockout (CKO) model, we show that neuronal Galc deletion is sufficient to cause growth and motor coordination defects and inflammatory gliosis in mice. Furthermore, psychosine accumulates significantly in the nervous system of neuron-specific Galc-CKO. Confocal and electron microscopic analyses show profound neuro-axonal degeneration with a mild effect on myelin structure. Thus, we prove for the first time that neuronal GALC is essential to maintain and protect neuronal function independently of myelin and may directly contribute to the pathogenesis of Krabbe disease.
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Affiliation(s)
- Conlan Kreher
- Institute for Myelin and Glia Exploration, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo—SUNY, Buffalo, New York, United States of America
| | - Jacob Favret
- Department of Biotechnical and Clinical Laboratory Sciences, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo—SUNY, Buffalo, New York, United States of America
| | - Nadav I. Weinstock
- Institute for Myelin and Glia Exploration, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo—SUNY, Buffalo, New York, United States of America
- Department of Neurology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo—SUNY, Buffalo, New York, United States of America
| | - Malabika Maulik
- Department of Biotechnical and Clinical Laboratory Sciences, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo—SUNY, Buffalo, New York, United States of America
| | - Xinying Hong
- Departments of Chemistry and Biochemistry, University of Washington, Seattle, Washington, United States of America
| | - Michael H. Gelb
- Departments of Chemistry and Biochemistry, University of Washington, Seattle, Washington, United States of America
| | - Lawrence Wrabetz
- Institute for Myelin and Glia Exploration, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo—SUNY, Buffalo, New York, United States of America
- Department of Neurology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo—SUNY, Buffalo, New York, United States of America
- Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo—SUNY, Buffalo, New York, United States of America
| | - M. Laura Feltri
- Institute for Myelin and Glia Exploration, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo—SUNY, Buffalo, New York, United States of America
- Department of Neurology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo—SUNY, Buffalo, New York, United States of America
- Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo—SUNY, Buffalo, New York, United States of America
| | - Daesung Shin
- Institute for Myelin and Glia Exploration, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo—SUNY, Buffalo, New York, United States of America
- Department of Biotechnical and Clinical Laboratory Sciences, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo—SUNY, Buffalo, New York, United States of America
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7
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Robinson RA, Griffiths SC, van de Haar LL, Malinauskas T, van Battum EY, Zelina P, Schwab RA, Karia D, Malinauskaite L, Brignani S, van den Munkhof MH, Düdükcü Ö, De Ruiter AA, Van den Heuvel DMA, Bishop B, Elegheert J, Aricescu AR, Pasterkamp RJ, Siebold C. Simultaneous binding of Guidance Cues NET1 and RGM blocks extracellular NEO1 signaling. Cell 2021; 184:2103-2120.e31. [PMID: 33740419 PMCID: PMC8063088 DOI: 10.1016/j.cell.2021.02.045] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 01/15/2021] [Accepted: 02/22/2021] [Indexed: 12/13/2022]
Abstract
During cell migration or differentiation, cell surface receptors are simultaneously exposed to different ligands. However, it is often unclear how these extracellular signals are integrated. Neogenin (NEO1) acts as an attractive guidance receptor when the Netrin-1 (NET1) ligand binds, but it mediates repulsion via repulsive guidance molecule (RGM) ligands. Here, we show that signal integration occurs through the formation of a ternary NEO1-NET1-RGM complex, which triggers reciprocal silencing of downstream signaling. Our NEO1-NET1-RGM structures reveal a "trimer-of-trimers" super-assembly, which exists in the cell membrane. Super-assembly formation results in inhibition of RGMA-NEO1-mediated growth cone collapse and RGMA- or NET1-NEO1-mediated neuron migration, by preventing formation of signaling-compatible RGM-NEO1 complexes and NET1-induced NEO1 ectodomain clustering. These results illustrate how simultaneous binding of ligands with opposing functions, to a single receptor, does not lead to competition for binding, but to formation of a super-complex that diminishes their functional outputs.
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Affiliation(s)
- Ross A Robinson
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Samuel C Griffiths
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Lieke L van de Haar
- Department of Translational Neuroscience, UMC Utrecht Brain Center, University Medical Center, Utrecht University, Universiteitsweg 100, 3584 CG Utrecht, the Netherlands
| | - Tomas Malinauskas
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Eljo Y van Battum
- Department of Translational Neuroscience, UMC Utrecht Brain Center, University Medical Center, Utrecht University, Universiteitsweg 100, 3584 CG Utrecht, the Netherlands
| | - Pavol Zelina
- Department of Translational Neuroscience, UMC Utrecht Brain Center, University Medical Center, Utrecht University, Universiteitsweg 100, 3584 CG Utrecht, the Netherlands
| | - Rebekka A Schwab
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Dimple Karia
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Lina Malinauskaite
- MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Sara Brignani
- Department of Translational Neuroscience, UMC Utrecht Brain Center, University Medical Center, Utrecht University, Universiteitsweg 100, 3584 CG Utrecht, the Netherlands
| | - Marleen H van den Munkhof
- Department of Translational Neuroscience, UMC Utrecht Brain Center, University Medical Center, Utrecht University, Universiteitsweg 100, 3584 CG Utrecht, the Netherlands
| | - Özge Düdükcü
- Department of Translational Neuroscience, UMC Utrecht Brain Center, University Medical Center, Utrecht University, Universiteitsweg 100, 3584 CG Utrecht, the Netherlands
| | - Anna A De Ruiter
- Department of Translational Neuroscience, UMC Utrecht Brain Center, University Medical Center, Utrecht University, Universiteitsweg 100, 3584 CG Utrecht, the Netherlands
| | - Dianne M A Van den Heuvel
- Department of Translational Neuroscience, UMC Utrecht Brain Center, University Medical Center, Utrecht University, Universiteitsweg 100, 3584 CG Utrecht, the Netherlands
| | - Benjamin Bishop
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Jonathan Elegheert
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - A Radu Aricescu
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK; MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - R Jeroen Pasterkamp
- Department of Translational Neuroscience, UMC Utrecht Brain Center, University Medical Center, Utrecht University, Universiteitsweg 100, 3584 CG Utrecht, the Netherlands.
| | - Christian Siebold
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK.
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8
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Haery L, Deverman BE, Matho KS, Cetin A, Woodard K, Cepko C, Guerin KI, Rego MA, Ersing I, Bachle SM, Kamens J, Fan M. Adeno-Associated Virus Technologies and Methods for Targeted Neuronal Manipulation. Front Neuroanat 2019; 13:93. [PMID: 31849618 PMCID: PMC6902037 DOI: 10.3389/fnana.2019.00093] [Citation(s) in RCA: 128] [Impact Index Per Article: 25.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Accepted: 10/30/2019] [Indexed: 12/14/2022] Open
Abstract
Cell-type-specific expression of molecular tools and sensors is critical to construct circuit diagrams and to investigate the activity and function of neurons within the nervous system. Strategies for targeted manipulation include combinations of classical genetic tools such as Cre/loxP and Flp/FRT, use of cis-regulatory elements, targeted knock-in transgenic mice, and gene delivery by AAV and other viral vectors. The combination of these complex technologies with the goal of precise neuronal targeting is a challenge in the lab. This report will discuss the theoretical and practical aspects of combining current technologies and establish best practices for achieving targeted manipulation of specific cell types. Novel applications and tools, as well as areas for development, will be envisioned and discussed.
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Affiliation(s)
| | - Benjamin E. Deverman
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA, United States
| | | | - Ali Cetin
- Allen Institute for Brain Science, Seattle, WA, United States
| | - Kenton Woodard
- Penn Vector Core, Gene Therapy Program, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Connie Cepko
- Department of Genetics, Harvard Medical School, Howard Hughes Medical Institute, Boston, MA, United States
- Department of Ophthalmology, Harvard Medical School, Howard Hughes Medical Institute, Boston, MA, United States
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9
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Bruggeman EC, Garretson JT, Wu R, Shi H, Xue B. Neuronal Dnmt1 Deficiency Attenuates Diet-Induced Obesity in Mice. Endocrinology 2018; 159:145-162. [PMID: 29145563 PMCID: PMC5761599 DOI: 10.1210/en.2017-00267] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2017] [Accepted: 11/09/2017] [Indexed: 12/22/2022]
Abstract
Aberrant neuronal DNA methylation patterns have been implicated in the promotion of obesity development; however, the role of neuronal DNA methyltransferases (Dnmts), enzymes that catalyze DNA methylation, in energy balance remains poorly understood. We investigated whether neuronal Dnmt1 regulates normal energy homeostasis and obesity development using a neuronal Dnmt1 knockout (ND1KO) mouse model, Dnmt1fl/fl Synapsin1Cre, which specifically deletes Dnmt1 in neurons. Neuronal Dnmt1 deficiency reduced adiposity in chow-fed mice and attenuated obesity in high-fat diet (HFD)-fed male mice. ND1KO male mice had reduced food intake and increased energy expenditure with the HFD. Furthermore, these mice had improved insulin sensitivity, as measured using an insulin tolerance test. The HFD-fed ND1KO mice had smaller fat pads and upregulation of thermogenic genes in brown adipose tissue. These data suggest that neuronal Dnmt1 plays an important role in regulating energy homeostasis. Notably, ND1KO male mice had elevated estrogen receptor-α (ERα) gene expression in the medial hypothalamus, which previously has been shown to control body weight. Immunohistochemistry experiments revealed that ERα protein expression was upregulated specifically in the dorsomedial region of the ventromedial hypothalamus, a region that might mediate the central effect of leptin. We conclude that neuronal Dnmt1 regulates energy homeostasis through pathways controlling food intake and energy expenditure. In addition, ERα expression in the dorsomedial region of the ventromedial hypothalamus might mediate these effects.
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MESH Headings
- Adipose Tissue, Brown/metabolism
- Adipose Tissue, Brown/pathology
- Adiposity
- Animals
- Crosses, Genetic
- DNA (Cytosine-5-)-Methyltransferase 1/deficiency
- DNA (Cytosine-5-)-Methyltransferase 1/genetics
- DNA (Cytosine-5-)-Methyltransferase 1/metabolism
- DNA Methylation
- Diet, High-Fat/adverse effects
- Energy Intake
- Energy Metabolism
- Estrogen Receptor alpha/genetics
- Estrogen Receptor alpha/metabolism
- Female
- Gene Expression Regulation
- Hypothalamus, Middle/enzymology
- Hypothalamus, Middle/metabolism
- Hypothalamus, Middle/pathology
- Insulin Resistance
- Male
- Mice, Knockout
- Mice, Transgenic
- Nerve Tissue Proteins/deficiency
- Nerve Tissue Proteins/genetics
- Nerve Tissue Proteins/metabolism
- Neurons/enzymology
- Neurons/metabolism
- Neurons/pathology
- Obesity/etiology
- Obesity/metabolism
- Obesity/pathology
- Obesity/prevention & control
- Promoter Regions, Genetic
- Sex Characteristics
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Affiliation(s)
- Emily C. Bruggeman
- Neuroscience Institute, Georgia State University,
Atlanta, Georgia 30302
- Center for Obesity Reversal, Georgia State University,
Atlanta, Georgia 30302
| | - John T. Garretson
- Neuroscience Institute, Georgia State University,
Atlanta, Georgia 30302
- Center for Obesity Reversal, Georgia State University,
Atlanta, Georgia 30302
| | - Rui Wu
- Center for Obesity Reversal, Georgia State University,
Atlanta, Georgia 30302
- Department of Biology, Georgia State University, Atlanta,
Georgia 30302
| | - Hang Shi
- Neuroscience Institute, Georgia State University,
Atlanta, Georgia 30302
- Center for Obesity Reversal, Georgia State University,
Atlanta, Georgia 30302
- Department of Biology, Georgia State University, Atlanta,
Georgia 30302
| | - Bingzhong Xue
- Neuroscience Institute, Georgia State University,
Atlanta, Georgia 30302
- Center for Obesity Reversal, Georgia State University,
Atlanta, Georgia 30302
- Department of Biology, Georgia State University, Atlanta,
Georgia 30302
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10
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Lopez TP, Giles K, Dugger BN, Oehler A, Condello C, Krejciova Z, Castaneda JA, Carlson GA, Prusiner SB. A novel vector for transgenesis in the rat CNS. Acta Neuropathol Commun 2017; 5:84. [PMID: 29157304 PMCID: PMC5697436 DOI: 10.1186/s40478-017-0484-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 10/18/2017] [Indexed: 01/11/2023] Open
Abstract
The larger brain of the rat enables a much greater repertoire of complex behaviors than mice, likely making rats preferential for investigating neurodegeneration. Because molecular tools for specific expression of transgenes in the rat brain are sparse, we chose Prnp encoding the prion protein (PrP) to develop a novel vector to drive transgene expression in the rat brain. We compared the rat Prnp sequence with mouse and Syrian hamster Prnp sequences, identifying conserved genetic elements and hypothesizing that these elements would be able to drive neuronal transgene expression. We investigated this by generating a vector termed RaPrnp that encompasses portions of the rat Prnp gene. Importantly, we replaced the rat Prnp open reading frame (ORF) with a cloning site for rapid and seamless In-Fusion cloning. To validate the in vivo neuronal specificity of the RaPrnp vector in rats, we generated stable RaPrnp-LacZ/enhanced green fluorescent protein (EGFP) transgenic (Tg) rat lines, which led to robust LacZ activity and high EGFP fluorescence in the central nervous system of embryos and adult animals. Next, we restored the rat Prnp ORF and generated multiple Tg(RaPrnp-PrP) lines, demonstrating that overexpression of Prnp accelerates the onset of scrapie. While the incubation time in wild-type (WT) rats was 175 ± 3 days post inoculation (dpi), one line, Tg2919, overexpressed RaPrPC at 4.4-fold and exhibited a reduced incubation time of 149 ± 2 dpi. The second line, Tg2922, overexpressed RaPrPC at 9.7-fold compared with WT animals and had an incubation time of 112 ± 0 dpi. Tg2922 rats inoculated with rat RML showed extensive vacuolation of the brainstem in contrast to WT and Tg2919 animals in which vacuolation was most prominent in the hippocampus and striatum as well as the motor and sensory cortices. It is possible that construction of Tg rats with modified phenotypes will prove more advantageous than mice for neurodegeneration studies.
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Affiliation(s)
- T Peter Lopez
- Institute for Neurodegenerative Diseases, Weill Institute for Neurosciences, University of California, San Francisco, Sandler Neurosciences Center, 675 Nelson Rising Lane, San Francisco, CA, 94158, USA
| | - Kurt Giles
- Institute for Neurodegenerative Diseases, Weill Institute for Neurosciences, University of California, San Francisco, Sandler Neurosciences Center, 675 Nelson Rising Lane, San Francisco, CA, 94158, USA
- Department of Neurology, University of California San Francisco, San Francisco, CA, 94158, USA
| | - Brittany N Dugger
- Institute for Neurodegenerative Diseases, Weill Institute for Neurosciences, University of California, San Francisco, Sandler Neurosciences Center, 675 Nelson Rising Lane, San Francisco, CA, 94158, USA
- Department of Neurology, University of California San Francisco, San Francisco, CA, 94158, USA
| | - Abby Oehler
- Institute for Neurodegenerative Diseases, Weill Institute for Neurosciences, University of California, San Francisco, Sandler Neurosciences Center, 675 Nelson Rising Lane, San Francisco, CA, 94158, USA
| | - Carlo Condello
- Institute for Neurodegenerative Diseases, Weill Institute for Neurosciences, University of California, San Francisco, Sandler Neurosciences Center, 675 Nelson Rising Lane, San Francisco, CA, 94158, USA
- Department of Neurology, University of California San Francisco, San Francisco, CA, 94158, USA
| | - Zuzana Krejciova
- Institute for Neurodegenerative Diseases, Weill Institute for Neurosciences, University of California, San Francisco, Sandler Neurosciences Center, 675 Nelson Rising Lane, San Francisco, CA, 94158, USA
| | - Julian A Castaneda
- Institute for Neurodegenerative Diseases, Weill Institute for Neurosciences, University of California, San Francisco, Sandler Neurosciences Center, 675 Nelson Rising Lane, San Francisco, CA, 94158, USA
| | - George A Carlson
- Institute for Neurodegenerative Diseases, Weill Institute for Neurosciences, University of California, San Francisco, Sandler Neurosciences Center, 675 Nelson Rising Lane, San Francisco, CA, 94158, USA
- Department of Neurology, University of California San Francisco, San Francisco, CA, 94158, USA
| | - Stanley B Prusiner
- Institute for Neurodegenerative Diseases, Weill Institute for Neurosciences, University of California, San Francisco, Sandler Neurosciences Center, 675 Nelson Rising Lane, San Francisco, CA, 94158, USA.
- Department of Neurology, University of California San Francisco, San Francisco, CA, 94158, USA.
- Department of Biochemistry and Biophysics, University of California, San Francisco, CA, 94158, USA.
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11
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Yamasaki T, Deki-Arima N, Kaneko A, Miyamura N, Iwatsuki M, Matsuoka M, Fujimori-Tonou N, Okamoto-Uchida Y, Hirayama J, Marth JD, Yamanashi Y, Kawasaki H, Yamanaka K, Penninger JM, Shibata S, Nishina H. Age-dependent motor dysfunction due to neuron-specific disruption of stress-activated protein kinase MKK7. Sci Rep 2017; 7:7348. [PMID: 28779160 PMCID: PMC5544763 DOI: 10.1038/s41598-017-07845-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Accepted: 07/03/2017] [Indexed: 11/23/2022] Open
Abstract
c-Jun N-terminal kinase (JNK) is a member of the mitogen-activated protein kinase family and controls various physiological processes including apoptosis. A specific upstream activator of JNKs is the mitogen-activated protein kinase kinase 7 (MKK7). It has been reported that MKK7-JNK signaling plays an important regulatory role in neural development, however, post-developmental functions in the nervous system have not been elucidated. In this study, we generated neuron-specific Mkk7 knockout mice (MKK7 cKO), which impaired constitutive activation of JNK in the nervous system. MKK7 cKO mice displayed impaired circadian behavioral rhythms and decreased locomotor activity. MKK7 cKO mice at 8 months showed motor dysfunctions such as weakness of hind-limb and gait abnormality in an age-dependent manner. Axonal degeneration in the spinal cord and muscle atrophy were also observed, along with accumulation of the axonal transport proteins JNK-interacting protein 1 and amyloid beta precursor protein in the brains and spinal cords of MKK7 cKO mice. Thus, the MKK7-JNK signaling pathway plays important roles in regulating circadian rhythms and neuronal maintenance in the adult nervous system.
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Affiliation(s)
- Tokiwa Yamasaki
- Department of Developmental and Regenerative Biology, Medical Research Institute, Tokyo Medical and Dental University (TMDU), 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Norie Deki-Arima
- Department of Developmental and Regenerative Biology, Medical Research Institute, Tokyo Medical and Dental University (TMDU), 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Asahito Kaneko
- Laboratory of Physiology and Pharmacology, School of Advanced Science and Engineering, Waseda University, Tokyo, Japan
| | - Norio Miyamura
- Department of Developmental and Regenerative Biology, Medical Research Institute, Tokyo Medical and Dental University (TMDU), 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Mamiko Iwatsuki
- Department of Hygiene and Public Health I, Tokyo Women's Medical University, Tokyo, Japan
| | - Masato Matsuoka
- Department of Hygiene and Public Health I, Tokyo Women's Medical University, Tokyo, Japan
| | - Noriko Fujimori-Tonou
- Laboratory for Molecular Dynamics of Mental Disorders, RIKEN Brain Science Institute, Wako, Saitama, 3510198, Japan
| | - Yoshimi Okamoto-Uchida
- Department of Developmental and Regenerative Biology, Medical Research Institute, Tokyo Medical and Dental University (TMDU), 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Jun Hirayama
- Department of Developmental and Regenerative Biology, Medical Research Institute, Tokyo Medical and Dental University (TMDU), 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Jamey D Marth
- Center for Nanomedicine, SBP Medical Discovery Institute, Department of Molecular, Cellular, and Developmental Biology, University of California Santa Barbara, Santa Barbara, California, USA
| | - Yuji Yamanashi
- Division of Genetics, Department of Cancer Biology, The Institute of Medical Science, The University of Tokyo, Shirokanedai, Minato-ku, Tokyo, 108-8639, Japan
| | - Hiroshi Kawasaki
- Department of Medical Neuroscience, Graduate School of Medical Sciences; Brain/Liver Interface Medicine Research Center, Kanazawa University, Kanazawa, Japan
| | - Koji Yamanaka
- Department of Neuroscience and Pathobiology, Research Institute of Environmental Medicine, Nagoya University, Nagoya, Japan
| | - Josef M Penninger
- IMBA, Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Vienna, Austria
| | - Shigenobu Shibata
- Laboratory of Physiology and Pharmacology, School of Advanced Science and Engineering, Waseda University, Tokyo, Japan
| | - Hiroshi Nishina
- Department of Developmental and Regenerative Biology, Medical Research Institute, Tokyo Medical and Dental University (TMDU), 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan.
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12
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Mosley M, Weathington J, Cortes LR, Bruggeman E, Castillo-Ruiz A, Xue B, Forger NG. Neonatal Inhibition of DNA Methylation Alters Cell Phenotype in Sexually Dimorphic Regions of the Mouse Brain. Endocrinology 2017; 158:1838-1848. [PMID: 28398586 PMCID: PMC5460944 DOI: 10.1210/en.2017-00205] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2017] [Accepted: 03/24/2017] [Indexed: 02/06/2023]
Abstract
Many of the best-studied neural sex differences relate to differences in cell number and are due to the hormonal control of developmental cell death. However, several prominent neural sex differences persist even if cell death is eliminated. We hypothesized that these may reflect cell phenotype "decisions" that depend on epigenetic mechanisms, such as DNA methylation. To test this, we treated newborn mice with the DNA methyltransferase (DNMT) inhibitor zebularine, or vehicle, and examined two sexually dimorphic markers at weaning. As expected, control males had more cells immunoreactive for calbindin-D28k (CALB) in the medial preoptic area (mPOA) and fewer cells immunoreactive for estrogen receptor α (ERα) in the ventrolateral portion of the ventromedial nucleus of the hypothalamus (VMHvl) and the mPOA than did females. Neonatal DNMT inhibition markedly increased CALB cell number in both sexes and ERα cell density in males; as a result, the sex differences in ERα in the VMHvl and mPOA were completely eliminated in zebularine-treated animals. Zebularine treatment did not affect developmental cell death or the total density of Nissl-stained cells at weaning. Thus, a neonatal disruption of DNA methylation apparently has long-term effects on the proportion of cells expressing CALB and ERα, and some of these effects are sex specific. We also found that sex differences in CALB in the mPOA and ERα in the VMHvl persist in mice with a neuron-specific depletion of either Dnmt1 or Dnmt3b, indicating that neither DNMT alone is likely to be required for the sexually dimorphic expression of these markers.
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Affiliation(s)
- Morgan Mosley
- Neuroscience Institute and Center for Behavioral Neuroscience, Georgia State University, Atlanta, Georgia 30302
| | - Jill Weathington
- Neuroscience Institute and Center for Behavioral Neuroscience, Georgia State University, Atlanta, Georgia 30302
| | - Laura R. Cortes
- Neuroscience Institute and Center for Behavioral Neuroscience, Georgia State University, Atlanta, Georgia 30302
| | - Emily Bruggeman
- Department of Biology, Neuroscience Institute and Center for Obesity Reversal, Georgia State University, Atlanta, Georgia 30302
| | - Alexandra Castillo-Ruiz
- Neuroscience Institute and Center for Behavioral Neuroscience, Georgia State University, Atlanta, Georgia 30302
| | - Bingzhong Xue
- Department of Biology, Neuroscience Institute and Center for Obesity Reversal, Georgia State University, Atlanta, Georgia 30302
| | - Nancy G. Forger
- Neuroscience Institute and Center for Behavioral Neuroscience, Georgia State University, Atlanta, Georgia 30302
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13
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Ercan E, Han JM, Di Nardo A, Winden K, Han MJ, Hoyo L, Saffari A, Leask A, Geschwind DH, Sahin M. Neuronal CTGF/CCN2 negatively regulates myelination in a mouse model of tuberous sclerosis complex. J Exp Med 2017; 214:681-697. [PMID: 28183733 PMCID: PMC5339668 DOI: 10.1084/jem.20160446] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Revised: 11/09/2016] [Accepted: 12/30/2016] [Indexed: 12/11/2022] Open
Abstract
Disruption of myelination during development has been implicated in a range of neurodevelopmental disorders including tuberous sclerosis complex (TSC). TSC patients with autism display impairments in white matter integrity. Similarly, mice lacking neuronal Tsc1 have a hypomyelination phenotype. However, the mechanisms that underlie these phenotypes remain unknown. In this study, we demonstrate that neuronal TSC1/2 orchestrates a program of oligodendrocyte maturation through the regulated secretion of connective tissue growth factor (CTGF). We characterize oligodendrocyte maturation both in vitro and in vivo. We find that neuron-specific Tsc1 deletion results in an increase in CTGF secretion that non-cell autonomously stunts oligodendrocyte development and decreases the total number of oligodendrocytes. Genetic deletion of CTGF from neurons, in turn, mitigates the TSC-dependent hypomyelination phenotype. These results show that the mechanistic target of rapamycin (mTOR) pathway in neurons regulates CTGF production and secretion, revealing a paracrine mechanism by which neuronal signaling regulates oligodendrocyte maturation and myelination in TSC. This study highlights the role of mTOR-dependent signaling between neuronal and nonneuronal cells in the regulation of myelin and identifies an additional therapeutic avenue for this disease.
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Affiliation(s)
- Ebru Ercan
- Department of Neurology, F.M. Kirby Center for Neurobiology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115
| | - Juliette M Han
- Department of Neurology, F.M. Kirby Center for Neurobiology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115
| | - Alessia Di Nardo
- Department of Neurology, F.M. Kirby Center for Neurobiology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115
| | - Kellen Winden
- Department of Neurology, F.M. Kirby Center for Neurobiology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115
| | - Min-Joon Han
- Department of Neurology, F.M. Kirby Center for Neurobiology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115.,Translational Neuroscience Center, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115
| | - Leonie Hoyo
- Department of Neurology, F.M. Kirby Center for Neurobiology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115.,Translational Neuroscience Center, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115
| | - Afshin Saffari
- Department of Neurology, F.M. Kirby Center for Neurobiology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115
| | - Andrew Leask
- Department of Dentistry, Schulich School of Medicine and Dentistry, London, Ontario N6A 5C1, Canada.,Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, London, Ontario N6A 5C1, Canada
| | - Daniel H Geschwind
- Department of Neurology, University of California, Los Angeles School of Medicine, Los Angeles, CA 90095.,Semel Institute, University of California, Los Angeles School of Medicine, Los Angeles, CA 90095.,Department of Human Genetics, University of California, Los Angeles School of Medicine, Los Angeles, CA 90095
| | - Mustafa Sahin
- Department of Neurology, F.M. Kirby Center for Neurobiology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115 .,Translational Neuroscience Center, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115
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14
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Naito-Matsui Y, Davies LRL, Takematsu H, Chou HH, Tangvoranuntakul P, Carlin AF, Verhagen A, Heyser CJ, Yoo SW, Choudhury B, Paton JC, Paton AW, Varki NM, Schnaar RL, Varki A. Physiological Exploration of the Long Term Evolutionary Selection against Expression of N-Glycolylneuraminic Acid in the Brain. J Biol Chem 2017; 292:2557-2570. [PMID: 28049733 DOI: 10.1074/jbc.m116.768531] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Revised: 12/26/2016] [Indexed: 12/18/2022] Open
Abstract
All vertebrate cell surfaces display a dense glycan layer often terminated with sialic acids, which have multiple functions due to their location and diverse modifications. The major sialic acids in most mammalian tissues are N-acetylneuraminic acid (Neu5Ac) and N-glycolylneuraminic acid (Neu5Gc), the latter being derived from Neu5Ac via addition of one oxygen atom at the sugar nucleotide level by CMP-Neu5Ac hydroxylase (Cmah). Contrasting with other organs that express various ratios of Neu5Ac and Neu5Gc depending on the variable expression of Cmah, Neu5Gc expression in the brain is extremely low in all vertebrates studied to date, suggesting that neural expression is detrimental to animals. However, physiological exploration of the reasons for this long term evolutionary selection has been lacking. To explore the consequences of forced expression of Neu5Gc in the brain, we have established brain-specific Cmah transgenic mice. Such Neu5Gc overexpression in the brain resulted in abnormal locomotor activity, impaired object recognition memory, and abnormal axon myelination. Brain-specific Cmah transgenic mice were also lethally sensitive to a Neu5Gc-preferring bacterial toxin, even though Neu5Gc was overexpressed only in the brain and other organs maintained endogenous Neu5Gc expression, as in wild-type mice. Therefore, the unusually strict evolutionary suppression of Neu5Gc expression in the vertebrate brain may be explained by evasion of negative effects on neural functions and by selection against pathogens.
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Affiliation(s)
- Yuko Naito-Matsui
- From the Departments of Medicine and Cellular and Molecular Medicine
| | - Leela R L Davies
- From the Departments of Medicine and Cellular and Molecular Medicine
| | - Hiromu Takematsu
- From the Departments of Medicine and Cellular and Molecular Medicine.,the Department of Human Health Sciences, Graduate School of Medicine, Kyoto University, Sakyo, Kyoto 606-8507, Japan
| | - Hsun-Hua Chou
- From the Departments of Medicine and Cellular and Molecular Medicine
| | | | - Aaron F Carlin
- From the Departments of Medicine and Cellular and Molecular Medicine
| | - Andrea Verhagen
- From the Departments of Medicine and Cellular and Molecular Medicine
| | | | | | | | - James C Paton
- the Research Centre for Infectious Diseases, Department of Molecular and Cellular Biology, School of Biological Sciences, University of Adelaide, Adelaide SA 5005, Australia
| | - Adrienne W Paton
- the Research Centre for Infectious Diseases, Department of Molecular and Cellular Biology, School of Biological Sciences, University of Adelaide, Adelaide SA 5005, Australia
| | - Nissi M Varki
- Department of Pathology, University of California San Diego, La Jolla, California 92093-0687
| | - Ronald L Schnaar
- Pharmacology and Neuroscience, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, and
| | - Ajit Varki
- From the Departments of Medicine and Cellular and Molecular Medicine, .,Glycobiology Research and Training Center, and
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15
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Huang CK, Lee SO, Chang E, Pang H, Chang C. Androgen receptor (AR) in cardiovascular diseases. J Endocrinol 2016; 229:R1-R16. [PMID: 26769913 PMCID: PMC4932893 DOI: 10.1530/joe-15-0518] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Accepted: 01/13/2016] [Indexed: 01/13/2023]
Abstract
Cardiovascular diseases (CVDs) are still the highest leading cause of death worldwide. Several risk factors have been linked to CVDs, including smoking, diabetes, hyperlipidemia, and gender among others. Sex hormones, especially the androgen and its receptor, androgen receptor (AR), have been linked to many diseases with a clear gender difference. Here, we summarize the effects of androgen/AR on CVDs, including hypertension, stroke, atherosclerosis, abdominal aortic aneurysm (AAA), myocardial hypertrophy, and heart failure, as well as the metabolic syndrome/diabetes and their impacts on CVDs. Androgen/AR signaling exacerbates hypertension, and anti-androgens may suppress hypertension. Androgen/AR signaling plays dual roles in strokes, depending on different kinds of factors; however, generally males have a higher incidence of strokes than females. Androgen and AR differentially modulate atherosclerosis. Androgen deficiency causes elevated lipid accumulation to enhance atherosclerosis; however, targeting AR in selective cells without altering serum androgen levels would suppress atherosclerosis progression. Androgen/AR signaling is crucial in AAA development and progression, and targeting androgen/AR profoundly restricts AAA progression. Men have increased cardiac hypertrophy compared with age-matched women that may be due to androgens. Finally, androgen/AR plays important roles in contributing to obesity and insulin/leptin resistance to increase the metabolic syndrome.
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Affiliation(s)
- Chiung-Kuei Huang
- George Whipple Lab for Cancer ResearchDepartments of Pathology, Urology, and The Wilmot Cancer Center, University of Rochester Medical Center, Rochester, NY, USA
| | - Soo Ok Lee
- George Whipple Lab for Cancer ResearchDepartments of Pathology, Urology, and The Wilmot Cancer Center, University of Rochester Medical Center, Rochester, NY, USA
| | - Eugene Chang
- George Whipple Lab for Cancer ResearchDepartments of Pathology, Urology, and The Wilmot Cancer Center, University of Rochester Medical Center, Rochester, NY, USA Department of MedicineCase Cardiovascular Institute Research Institute, Case Western Reserve University, Cleveland, OH, USA
| | - Haiyan Pang
- George Whipple Lab for Cancer ResearchDepartments of Pathology, Urology, and The Wilmot Cancer Center, University of Rochester Medical Center, Rochester, NY, USA
| | - Chawnshang Chang
- George Whipple Lab for Cancer ResearchDepartments of Pathology, Urology, and The Wilmot Cancer Center, University of Rochester Medical Center, Rochester, NY, USA Sex Hormone Research CenterChina Medical University/Hospital, Taichung, Taiwan
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16
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Hristova M, Rocha-Ferreira E, Fontana X, Thei L, Buckle R, Christou M, Hompoonsup S, Gostelow N, Raivich G, Peebles D. Inhibition of Signal Transducer and Activator of Transcription 3 (STAT3) reduces neonatal hypoxic-ischaemic brain damage. J Neurochem 2016; 136:981-94. [PMID: 26669927 PMCID: PMC4843952 DOI: 10.1111/jnc.13490] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Revised: 11/08/2015] [Accepted: 12/04/2015] [Indexed: 01/01/2023]
Abstract
Hypoxic‐ischaemic encephalopathy is a leading cause of child death, with high mortality and morbidity, including cerebral palsy, epilepsy and cognitive disabilities. Hypoxia‐ischaemia (HI) strongly up‐regulates Signal Transducer and Activator of Transcription 3 (STAT3) in the immature brain. Our aim was to establish whether STAT3 up‐regulation is associated with neonatal HI‐brain damage and evaluate the phosphorylated STAT3‐contribution from different cell types in eliciting damage. We subjected postnatal day seven mice to unilateral carotid artery ligation followed by 60 min hypoxia. Neuronal STAT3‐deletion reduced cell death, tissue loss, microglial and astroglial activation in all brain regions. Astroglia‐specific STAT3‐deletion also reduced cell death, tissue loss and microglial activation, although not as strongly as the deletion in neurons. Systemic pre‐insult STAT3‐blockade at tyrosine 705 (Y705) with JAK2‐inhibitor WP1066 reduced microglial and astroglial activation to a more moderate degree, but in a pattern similar to the one produced by the cell‐specific deletions. Our results suggest that STAT3 is a crucial factor in neonatal HI‐brain damage and its removal in neurons or astrocytes, and, to some extent, inhibition of its phosphorylation via JAK2‐blockade reduces inflammation and tissue loss. Overall, the protective effects of STAT3 inactivation make it a possible target for a therapeutic strategy in neonatal HI.
Current data show that neuronal and astroglial STAT3 molecules are involved in the pathways underlying cell death, tissue loss and gliosis following neonatal hypoxia‐ischaemia, but differ with respect to the target of their effect. Y705‐phosphorylation contributes to hypoxic‐ischaemic histopathology. Protective effects of STAT3 inactivation make it a possible target for a therapeutic strategy in neonatal hypoxia‐ischaemia.
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Affiliation(s)
- Mariya Hristova
- UCL Institute for Women's Health, Maternal & Fetal Medicine, Perinatal Brain Repair Group, London WC1E 6HX, UK
| | - Eridan Rocha-Ferreira
- UCL Institute for Women's Health, Maternal & Fetal Medicine, Perinatal Brain Repair Group, London WC1E 6HX, UK
| | - Xavier Fontana
- Cell Growth and Regeneration Lab, MRC Laboratory for Molecular Cell Biology, University College London, WC1E 6BT, UK
| | - Laura Thei
- UCL Institute for Women's Health, Maternal & Fetal Medicine, Perinatal Brain Repair Group, London WC1E 6HX, UK
| | - Rheanan Buckle
- UCL Institute for Women's Health, Maternal & Fetal Medicine, Perinatal Brain Repair Group, London WC1E 6HX, UK
| | - Melina Christou
- UCL Institute for Women's Health, Maternal & Fetal Medicine, Perinatal Brain Repair Group, London WC1E 6HX, UK
| | - Supanida Hompoonsup
- UCL Institute for Women's Health, Maternal & Fetal Medicine, Perinatal Brain Repair Group, London WC1E 6HX, UK
| | - Naomi Gostelow
- UCL Institute for Women's Health, Maternal & Fetal Medicine, Perinatal Brain Repair Group, London WC1E 6HX, UK
| | - Gennadij Raivich
- UCL Institute for Women's Health, Maternal & Fetal Medicine, Perinatal Brain Repair Group, London WC1E 6HX, UK
| | - Donald Peebles
- UCL Institute for Women's Health, Maternal & Fetal Medicine, Perinatal Brain Repair Group, London WC1E 6HX, UK
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17
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Shumar SA, Fagone P, Alfonso-Pecchio A, Gray JT, Rehg JE, Jackowski S, Leonardi R. Induction of Neuron-Specific Degradation of Coenzyme A Models Pantothenate Kinase-Associated Neurodegeneration by Reducing Motor Coordination in Mice. PLoS One 2015; 10:e0130013. [PMID: 26052948 PMCID: PMC4460045 DOI: 10.1371/journal.pone.0130013] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Accepted: 05/15/2015] [Indexed: 02/01/2023] Open
Abstract
BACKGROUND Pantothenate kinase-associated neurodegeneration, PKAN, is an inherited disorder characterized by progressive impairment in motor coordination and caused by mutations in PANK2, a human gene that encodes one of four pantothenate kinase (PanK) isoforms. PanK initiates the synthesis of coenzyme A (CoA), an essential cofactor that plays a key role in energy metabolism and lipid synthesis. Most of the mutations in PANK2 reduce or abolish the activity of the enzyme. This evidence has led to the hypothesis that lower CoA might be the underlying cause of the neurodegeneration in PKAN patients; however, no mouse model of the disease is currently available to investigate the connection between neuronal CoA levels and neurodegeneration. Indeed, genetic and/or dietary manipulations aimed at reducing whole-body CoA synthesis have not produced a desirable PKAN model, and this has greatly hindered the discovery of a treatment for the disease. OBJECTIVE, METHODS, RESULTS AND CONCLUSIONS Cellular CoA levels are tightly regulated by a balance between synthesis and degradation. CoA degradation is catalyzed by two peroxisomal nudix hydrolases, Nudt7 and Nudt19. In this study we sought to reduce neuronal CoA in mice through the alternative approach of increasing Nudt7-mediated CoA degradation. This was achieved by combining the use of an adeno-associated virus-based expression system with the synapsin (Syn) promoter. We show that mice with neuronal overexpression of a cytosolic version of Nudt7 (scAAV9-Syn-Nudt7cyt) exhibit a significant decrease in brain CoA levels in conjunction with a reduction in motor coordination. These results strongly support the existence of a link between CoA levels and neuronal function and show that scAAV9-Syn-Nudt7cyt mice can be used to model PKAN.
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Affiliation(s)
- Stephanie A. Shumar
- Department of Biochemistry, School of Medicine, West Virginia University, Morgantown, West Virginia, United States of America
| | - Paolo Fagone
- Department of Hematology, St. Jude Children’s Research Hospital, Memphis, Tennessee, United States of America
| | - Adolfo Alfonso-Pecchio
- Department of Infectious Diseases, St. Jude Children’s Research Hospital, Memphis, Tennessee, United States of America
| | - John T. Gray
- Department of Hematology, St. Jude Children’s Research Hospital, Memphis, Tennessee, United States of America
| | - Jerold E. Rehg
- Department of Pathology, St. Jude Children’s Research Hospital, Memphis, Tennessee, United States of America
| | - Suzanne Jackowski
- Department of Infectious Diseases, St. Jude Children’s Research Hospital, Memphis, Tennessee, United States of America
| | - Roberta Leonardi
- Department of Biochemistry, School of Medicine, West Virginia University, Morgantown, West Virginia, United States of America
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Dingledine R, Varvel NH, Dudek FE. When and how do seizures kill neurons, and is cell death relevant to epileptogenesis? ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2014; 813:109-22. [PMID: 25012371 PMCID: PMC4624106 DOI: 10.1007/978-94-017-8914-1_9] [Citation(s) in RCA: 139] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
The effect of seizures on neuronal death and the role of seizure-induced neuronal death in acquired epileptogenesis have been debated for decades. Isolated brief seizures probably do not kill neurons; however, severe and repetitive seizures (i.e., status epilepticus) certainly do. Because status epilepticus both kills neurons and also leads to chronic epilepsy, neuronal death has been proposed to be an integral part of acquired epileptogenesis. Several studies, particularly in the immature brain, have suggested that neuronal death is not necessary for acquired epileptogenesis; however, the lack of neuronal death is difficult if not impossible to prove, and more recent studies have challenged this concept. Novel mechanisms of cell death, beyond the traditional concepts of necrosis and apoptosis, include autophagy, phagoptosis, necroptosis, and pyroptosis. The traditional proposal for why neuronal death may be necessary for epileptogenesis is based on the recapitulation of development hypothesis, where a loss of synaptic input from the dying neurons is considered a critical signal to induce axonal sprouting and synaptic-circuit reorganization. We propose a second hypothesis - the neuronal death pathway hypothesis, which states that the biochemical pathways causing programmed neurodegeneration, rather than neuronal death per se, are responsible for or contribute to epileptogenesis. The reprogramming of neuronal death pathways - if true - is proposed to derive from necroptosis or pyroptosis. The proposed new hypothesis may inform on why neuronal death seems closely linked to epileptogenesis, but may not always be.
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Affiliation(s)
- Ray Dingledine
- Department of Pharmacology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Nicholas H. Varvel
- Department of Pharmacology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - F. Edward Dudek
- Department of Neurosurgery, University of Utah School of Medicine, Salt Lake City, UT 84108, USA
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Matsuzaki Y, Oue M, Hirai H. Generation of a neurodegenerative disease mouse model using lentiviral vectors carrying an enhanced synapsin I promoter. J Neurosci Methods 2013; 223:133-43. [PMID: 24361760 DOI: 10.1016/j.jneumeth.2013.12.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Revised: 11/26/2013] [Accepted: 12/05/2013] [Indexed: 11/15/2022]
Abstract
BACKGROUND Certain inherited progressive neurodegenerative disorders, such as spinocerebellar ataxia (SCA), affect neurons in large areas of the central nervous system (CNS). The selective expression of disease-causing and therapeutic genes in susceptible regions and cell types is critical for the generation of animal models and development of gene therapies for these diseases. Previous studies have demonstrated the advantages of the short synapsin I (SynI) promoter (0.5 kb) as a neuron-specific promoter for robust transgene expression. However, the short SynI promoter has also shown some promoter activity in glia and a lack of transgene expression in significant areas of the CNS. New methods: To improve the SynI promoter, we used a SynI promoter that is twice as long (1.0 kb) as the short SynI promoter and incorporated a minimal CMV (minCMV) sequence. RESULTS We observed that the 1.0 kb rat SynI promoter with minCMV [rSynI(1.0)-minCMV] exhibited robust promoter strength, excellent neuronal specificity and wide-ranging transgene expression throughout the CNS. Comparison with existing methods: Compared with the two previously reported short (0.5 kb) promoters, the new promoter was superior with respect to neuronal specificity and more efficiently transduced neurons. Moreover, transgenic mice expressing the mutant protein ATXN1[Q98], which causes SCA type 1 (SCA1), under the control of the rSynI(1.0)-minCMV promoter showed robust transgene expression specifically in neurons throughout the CNS and exhibited progressive ataxia. CONCLUSION rSynI(1.0)-minCMV drives robust and neuron-specific transgene expression throughout the CNS and is therefore useful for viral vector-mediated neuron-specific gene delivery and generation of neuron-specific transgenic animals.
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Affiliation(s)
- Yasunori Matsuzaki
- Department of Neurophysiology, Gunma University Graduate School of Medicine, Maebashi, Gunma 371-8511, Japan
| | - Miho Oue
- Department of Neurophysiology, Gunma University Graduate School of Medicine, Maebashi, Gunma 371-8511, Japan
| | - Hirokazu Hirai
- Department of Neurophysiology, Gunma University Graduate School of Medicine, Maebashi, Gunma 371-8511, Japan.
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Yaguchi M, Ohashi Y, Tsubota T, Sato A, Koyano KW, Wang N, Miyashita Y. Characterization of the properties of seven promoters in the motor cortex of rats and monkeys after lentiviral vector-mediated gene transfer. Hum Gene Ther Methods 2013; 24:333-44. [PMID: 23964981 DOI: 10.1089/hgtb.2012.238] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Lentiviral vectors deliver transgenes efficiently to a wide range of neuronal cell types in the mammalian central nervous system. To drive gene expression, internal promoters are essential; however, the in vivo properties of promoters, such as their cell type specificity and gene expression activity, are not well known, especially in the nonhuman primate brain. Here, the properties of five ubiquitous promoters (murine stem cell virus [MSCV], cytomegalovirus [CMV], CMV early enhancer/chicken β-actin [CAG], human elongation factor-1α [EF-1α], and Rous sarcoma virus [RSV]) and two cell type-specific promoters (rat synapsin I and mouse α-calcium/calmodulin-dependent protein kinase II [CaMKIIα]) in rat and monkey motor cortices in vivo were characterized. Vesicular stomatitis virus G (VSV-G)-pseudotyped lentiviral vectors expressing enhanced green fluorescent protein (EGFP) under the control of the various promoters were prepared and injected into rat and monkey motor cortices. Immunohistochemical analysis revealed that all of the VSV-G-pseudotyped lentiviral vectors had strong endogenous neuronal tropisms in rat and monkey brains. Among the seven promoters, the CMV promoter showed modest expression in glial cells (9.4%) of the rat brain, whereas the five ubiquitous promoters (MSCV, CMV, CAG, EF-1α, and RSV) showed expression in glial cells (7.0-14.7%) in the monkey brain. Cell type-specific synapsin I and CaMKIIα promoters showed excitatory neuron-specific expression in the monkey brain (synapsin I, 99.7%; CaMKIIα, 100.0%), but their specificities for excitatory neurons were significantly lower in the rat brain (synapsin I, 94.6%; CaMKIIα, 93.7%). These findings could be useful in basic and clinical neuroscience research for the design of vectors that efficiently deliver and express transgenes into rat and monkey brains.
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Affiliation(s)
- Masae Yaguchi
- 1 Department of Physiology, The University of Tokyo School of Medicine , Tokyo 113-0033, Japan
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21
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Hedegaard C, Kjaer-Sorensen K, Madsen LB, Henriksen C, Momeni J, Bendixen C, Oxvig C, Larsen K. Porcine synapsin 1: SYN1 gene analysis and functional characterization of the promoter. FEBS Open Bio 2013; 3:411-20. [PMID: 24251104 PMCID: PMC3821028 DOI: 10.1016/j.fob.2013.10.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2013] [Revised: 10/01/2013] [Accepted: 10/01/2013] [Indexed: 11/22/2022] Open
Abstract
Synapsin 1 (SYN1) is a phosphoprotein involved in nerve signal transmission. The porcine SYN1 promoter orthologue was cloned and characterized to provide a means of expressing a transgene specifically in neurons. The nucleotide sequence of the promoter displayed a high degree of conservation of elements responsible for neuron-specific expression. Expression analysis of SYN1 demonstrated presence of transcript during embryonic development. Analysis of GFP expression in transgenic zebrafish embryos suggests that the pig SYN1 promoter directs expression in neuronal cells. Thus, the SYN1 promoter is a good candidate for use in the generation of pig models of human neurodegenerative disorders. The porcine synapsin1 (SYN1) promoter was cloned and characterized. SYN1 mRNA expression is detected in brain during embryo development. The SYN1 gene is mapped to pig chromosome X. Porcine SYN1 directs GFP expression in neuronal cells of transgenic zebrafish.
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Key Words
- Ab, antibody
- BSG, basal ganglia
- BST, brain stem
- CBE, cerebellum
- CMV, cytomegalovirus
- Chr, chromosome
- FB, forebrain
- FCO, frontal cortex
- GFP
- GFP, green fluorescent protein
- HB, hindbrain
- HIP, hippocampus
- LLG, lateral line ganglion
- MB, midbrain
- NRSE, neuron restrictive silencer element
- Neuron-specific promoter
- OC, optic chiasm
- ON, olfactory neuron
- Pig
- R, retina
- REST, RE1-silencing transcription factor
- TG, trigeminal ganglion
- TSS, transcription start site
- Transgenic
- WPRE, Woodchuck hepatitits virus Post-transcriptional Regulatory Element
- Zebrafish
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Affiliation(s)
- Claus Hedegaard
- Department of Molecular Biology and Genetics, Aarhus University, Blichers Alle 20, Tjele DK-8830, Denmark
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22
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Abstract
Nestin-Cre mice have a significant metabolic phenotype that is hard to discern from current literature. Indeed, the Cre-lox system has numerous problems that can affect physiological parameters, and these are missed when the correct control strains are not used. Despite the increasing use of the Cre-lox system, these issues were not visible to the scientific community previously and may have affected published work. This makes it important to highlight the issues and raise awareness of the pitfalls of the Cre-lox system. Therefore, this perspective will discuss the impact of CNS and peripheral "off-target" Cre recombination on metabolic systems and describe the development of new approaches to obviate the difficulties.
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Affiliation(s)
- Erika Harno
- Neuroscience Research Group, Faculty of Life Sciences, University of Manchester, Manchester M13 9PT, UK
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Vaghi V, Pennucci R, Talpo F, Corbetta S, Montinaro V, Barone C, Croci L, Spaiardi P, Consalez GG, Biella G, de Curtis I. Rac1 and rac3 GTPases control synergistically the development of cortical and hippocampal GABAergic interneurons. ACTA ACUST UNITED AC 2012; 24:1247-58. [PMID: 23258346 PMCID: PMC3977619 DOI: 10.1093/cercor/bhs402] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The intracellular mechanisms driving postmitotic development of cortical γ-aminobutyric acid (GABA)ergic interneurons are poorly understood. We have addressed the function of Rac GTPases in cortical and hippocampal interneuron development. Developing neurons express both Rac1 and Rac3. Previous work has shown that Rac1 ablation does not affect the development of migrating cortical interneurons. Analysis of mice with double deletion of Rac1 and Rac3 shows that these GTPases are required during postmitotic interneuron development. The number of parvalbumin-positive cells was affected in the hippocampus and cortex of double knockout mice. Rac depletion also influences the maturation of interneurons that reach their destination, with reduction of inhibitory synapses in both hippocampal CA1 and cortical pyramidal cells. The decreased number of cortical migrating interneurons and their altered morphology indicate a role of Rac1 and Rac3 in regulating the motility of cortical interneurons, thus interfering with their final localization. While electrophysiological passive and active properties of pyramidal neurons including membrane capacity, resting potential, and spike amplitude and duration were normal, these cells showed reduced spontaneous inhibitory currents and increased excitability. Our results show that Rac1 and Rac3 contribute synergistically to postmitotic development of specific populations of GABAergic cells, suggesting that these proteins regulate their migration and differentiation.
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Affiliation(s)
- Valentina Vaghi
- Division of Neuroscience, San Raffaele Scientific Institute, 20132 Milan, Italy
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24
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Paonessa F, Latifi S, Scarongella H, Cesca F, Benfenati F. Specificity protein 1 (Sp1)-dependent activation of the synapsin I gene (SYN1) is modulated by RE1-silencing transcription factor (REST) and 5'-cytosine-phosphoguanine (CpG) methylation. J Biol Chem 2012; 288:3227-39. [PMID: 23250796 PMCID: PMC3561544 DOI: 10.1074/jbc.m112.399782] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
The development and function of the nervous system are directly dependent on a well defined pattern of gene expression. Indeed, perturbation of transcriptional activity or epigenetic modifications of chromatin can dramatically influence neuronal phenotypes. The phosphoprotein synapsin I (Syn I) plays a crucial role during axonogenesis and synaptogenesis as well as in synaptic transmission and plasticity of mature neurons. Abnormalities in SYN1 gene expression have been linked to important neuropsychiatric disorders, such as epilepsy and autism. SYN1 gene transcription is suppressed in non-neural tissues by the RE1-silencing transcription factor (REST); however, the molecular mechanisms that allow the constitutive expression of this genetic region in neurons have not been clarified yet. Herein we demonstrate that a conserved region of human and mouse SYN1 promoters contains cis-sites for the transcriptional activator Sp1 in close proximity to REST binding motifs. Through a series of functional assays, we demonstrate a physical interaction of Sp1 on the SYN1 promoter and show that REST directly inhibits Sp1-mediated transcription, resulting in SYN1 down-regulation. Upon differentiation of neuroblastoma Neuro2a cells, we observe a decrease in endogenous REST and a higher stability of Sp1 on target GC boxes, resulting in an increase of SYN1 transcription. Moreover, methylation of Sp1 cis-sites in the SYN1 promoter region could provide an additional level of transcriptional regulation. Our results introduce Sp1 as a fundamental activator of basal SYN1 gene expression, whose activity is modulated by the neural master regulator REST and CpG methylation.
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Affiliation(s)
- Francesco Paonessa
- Department of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, via Morego 30, 16163 Genova, Italy
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25
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Rit GTPase regulates a p38 MAPK-dependent neuronal survival pathway. Neurosci Lett 2012; 531:125-30. [PMID: 23123784 DOI: 10.1016/j.neulet.2012.10.036] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2012] [Revised: 10/12/2012] [Accepted: 10/22/2012] [Indexed: 11/24/2022]
Abstract
Rit, along with Rin and Drosophila Ric, comprises the Rit subfamily of Ras-related small GTPases. Although the cellular functions of many Ras family GTPases are well established, the physiological significance of Rit remains poorly understood. Loss of Rit sensitizes multiple mammalian cell lines and mouse embryonic fibroblasts (MEFs) derived from Rit(-/-) mice to oxidative stress-mediated apoptosis. However, whether Rit-mediated pro-survival signaling extends to other cell types, particularly neurons, is presently unknown. Here, to examine these issues we generated a transgenic mouse overexpressing constitutively active Rit (Rit(Q79L)) exclusively in neurons, under control of the Synapsin I promoter. Active Rit-expressing hippocampal neurons display a dramatic increase in oxidative stress resistance. Moreover, pharmacological inhibitor studies demonstrate that p38 MAPK, rather than a MEK/ERK signaling cascade, is required for Rit-mediated protection. Together, the present studies identify a critical role for the Rit-p38 MAPK signaling cascade in promoting hippocampal neuron survival following oxidative stress.
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26
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Fontana X, Hristova M, Da Costa C, Patodia S, Thei L, Makwana M, Spencer-Dene B, Latouche M, Mirsky R, Jessen KR, Klein R, Raivich G, Behrens A. c-Jun in Schwann cells promotes axonal regeneration and motoneuron survival via paracrine signaling. J Cell Biol 2012; 198:127-41. [PMID: 22753894 PMCID: PMC3392945 DOI: 10.1083/jcb.201205025] [Citation(s) in RCA: 197] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2012] [Accepted: 06/04/2012] [Indexed: 11/22/2022] Open
Abstract
The AP-1 transcription factor c-Jun is a master regulator of the axonal response in neurons. c-Jun also functions as a negative regulator of myelination in Schwann cells (SCs) and is strongly reactivated in SCs upon axonal injury. We demonstrate here that, after injury, the absence of c-Jun specifically in SCs caused impaired axonal regeneration and severely increased neuronal cell death. c-Jun deficiency resulted in decreased expression of several neurotrophic factors, and GDNF and Artemin, both of which encode ligands for the Ret receptor tyrosine kinase, were identified as novel direct c-Jun target genes. Genetic inactivation of Ret specifically in neurons resulted in regeneration defects without affecting motoneuron survival and, conversely, administration of recombinant GDNF and Artemin protein substantially ameliorated impaired regeneration caused by c-Jun deficiency. These results reveal an unexpected function for c-Jun in SCs in response to axonal injury, and identify paracrine Ret signaling as an important mediator of c-Jun function in SCs during regeneration.
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Affiliation(s)
- Xavier Fontana
- Mammalian Genetics Laboratory and Experimental Pathology Laboratory, Cancer Research UK, London Research Institute, London WC2A 3LY, England, UK
| | - Mariya Hristova
- Perinatal Brain Repair Group, Department of Obstetrics and Gynaecology, University College London, London WC1E 6HX, England, UK
| | - Clive Da Costa
- Mammalian Genetics Laboratory and Experimental Pathology Laboratory, Cancer Research UK, London Research Institute, London WC2A 3LY, England, UK
| | - Smriti Patodia
- Perinatal Brain Repair Group, Department of Obstetrics and Gynaecology, University College London, London WC1E 6HX, England, UK
| | - Laura Thei
- Perinatal Brain Repair Group, Department of Obstetrics and Gynaecology, University College London, London WC1E 6HX, England, UK
| | - Milan Makwana
- Perinatal Brain Repair Group, Department of Obstetrics and Gynaecology, University College London, London WC1E 6HX, England, UK
| | - Bradley Spencer-Dene
- Mammalian Genetics Laboratory and Experimental Pathology Laboratory, Cancer Research UK, London Research Institute, London WC2A 3LY, England, UK
| | - Morwena Latouche
- Research Department of Cell and Developmental Biology, University College London, London WC1E 6BT, England, UK
| | - Rhona Mirsky
- Research Department of Cell and Developmental Biology, University College London, London WC1E 6BT, England, UK
| | - Kristjan R. Jessen
- Research Department of Cell and Developmental Biology, University College London, London WC1E 6BT, England, UK
| | - Rüdiger Klein
- Department of Molecular Neurobiology, Max Planck Institute of Neurobiology, 82152 Munich-Martinsried, Germany
| | - Gennadij Raivich
- Perinatal Brain Repair Group, Department of Obstetrics and Gynaecology, University College London, London WC1E 6HX, England, UK
| | - Axel Behrens
- Mammalian Genetics Laboratory and Experimental Pathology Laboratory, Cancer Research UK, London Research Institute, London WC2A 3LY, England, UK
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27
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Ruff CA, Staak N, Patodia S, Kaswich M, Rocha-Ferreira E, Da Costa C, Brecht S, Makwana M, Fontana X, Hristova M, Rumajogee P, Galiano M, Bohatschek M, Herdegen T, Behrens A, Raivich G. Neuronal c-Jun is required for successful axonal regeneration, but the effects of phosphorylation of its N-terminus are moderate. J Neurochem 2012; 121:607-18. [PMID: 22372722 PMCID: PMC4491308 DOI: 10.1111/j.1471-4159.2012.07706.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2012] [Revised: 02/05/2012] [Accepted: 02/21/2012] [Indexed: 12/18/2022]
Abstract
Although neural c-Jun is essential for successful peripheral nerve regeneration, the cellular basis of this effect and the impact of c-Jun activation are incompletely understood. In the current study, we explored the effects of neuron-selective c-Jun deletion, substitution of serine 63 and 73 phosphoacceptor sites with non-phosphorylatable alanine, and deletion of Jun N-terminal kinases 1, 2 and 3 in mouse facial nerve regeneration. Removal of the floxed c-jun gene in facial motoneurons using cre recombinase under control of a neuron-specific synapsin promoter (junΔS) abolished basal and injury-induced neuronal c-Jun immunoreactivity, as well as most of the molecular responses following facial axotomy. Absence of neuronal Jun reduced the speed of axonal regeneration following crush, and prevented most cut axons from reconnecting to their target, significantly reducing functional recovery. Despite blocking cell death, this was associated with a large number of shrunken neurons. Finally, junΔS mutants also had diminished astrocyte and microglial activation and T-cell influx, suggesting that these non-neuronal responses depend on the release of Jun-dependent signals from neighboring injured motoneurons. The effects of substituting serine 63 and 73 phosphoacceptor sites (junAA), or of global deletion of individual kinases responsible for N-terminal c-Jun phosphorylation were mild. junAA mutants showed decrease in neuronal cell size, a moderate reduction in post-axotomy CD44 levels and slightly increased astrogliosis. Deletion of Jun N-terminal kinase (JNK)1 or JNK3 showed delayed functional recovery; deletion of JNK3 also interfered with T-cell influx, and reduced CD44 levels. Deletion of JNK2 had no effect. Thus, neuronal c-Jun is needed in regeneration, but JNK phosphorylation of the N-terminus mostly appears to not be required for its function.
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Affiliation(s)
- Crystal A Ruff
- Perinatal Brain Repair Group, Inst Women's Health, University College London, London, UK
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28
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Lee HM, Greeley GH, Englander EW. Transgenic overexpression of neuroglobin attenuates formation of smoke-inhalation-induced oxidative DNA damage, in vivo, in the mouse brain. Free Radic Biol Med 2011; 51:2281-7. [PMID: 22001746 PMCID: PMC3241998 DOI: 10.1016/j.freeradbiomed.2011.09.026] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2011] [Revised: 09/16/2011] [Accepted: 09/20/2011] [Indexed: 12/15/2022]
Abstract
Acute inhalation of combustion smoke causes neurological deficits in survivors. Inhaled smoke includes carbon monoxide, noxious gases, and a hypoxic environment, which disrupt oxygenation and generate free radicals. To replicate a smoke-inhalation scenario, we developed an experimental model of acute exposure to smoke for the awake mouse/rat and detected induction of biomarkers of oxidative stress. These include inhibition of mitochondrial respiratory complexes and formation of oxidative DNA damage in the brain. DNA damage is likely to contribute to neuronal dysfunction and progression of brain injury. In the search for strategies to attenuate the smoke-initiated brain injury, we produced a transgenic mouse overexpressing the neuronal globin protein neuroglobin. Neuroglobin was neuroprotective in diverse models of ischemic/hypoxic/toxic brain injuries. Here, we report lesser inhibition of respiratory complex I and reduced formation of smoke-induced DNA damage in neuroglobin transgenic compared to wild-type mouse brain. DNA damage was assessed using the standard comet assay, as well as a modified comet assay done in conjunction with an enzyme that excises oxidized guanines that form readily under conditions of oxidative stress. Both comet assays revealed that overexpressed neuroglobin attenuates the formation of oxidative DNA damage, in vivo, in the brain. These findings suggest that elevated neuroglobin exerts neuroprotection, in part, by decreasing the impact of acute smoke inhalation on the integrity of neuronal DNA.
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Affiliation(s)
- Heung Man Lee
- Department of Surgery, University of Texas Medical Branch, Galveston, TX 77555, USA
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29
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Sanuki R, Onishi A, Koike C, Muramatsu R, Watanabe S, Muranishi Y, Irie S, Uneo S, Koyasu T, Matsui R, Chérasse Y, Urade Y, Watanabe D, Kondo M, Yamashita T, Furukawa T. miR-124a is required for hippocampal axogenesis and retinal cone survival through Lhx2 suppression. Nat Neurosci 2011; 14:1125-34. [PMID: 21857657 DOI: 10.1038/nn.2897] [Citation(s) in RCA: 224] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2011] [Accepted: 06/30/2011] [Indexed: 02/07/2023]
Abstract
MicroRNA-124a (miR-124a) is the most abundant microRNA expressed in the vertebrate CNS. Despite past investigations into the role of miR-124a, inconsistent results have left the in vivo function of miR-124a unclear. We examined the in vivo function of miR-124a by targeted disruption of Rncr3 (retinal non-coding RNA 3), the dominant source of miR-124a. Rncr3(-/-) mice exhibited abnormalities in the CNS, including small brain size, axonal mis-sprouting of dentate gyrus granule cells and retinal cone cell death. We found that Lhx2 is an in vivo target mRNA of miR-124a. We also observed that LHX2 downregulation by miR-124a is required for the prevention of apoptosis in the developing retina and proper axonal development of hippocampal neurons. These results suggest that miR-124a is essential for the maturation and survival of dentate gyrus neurons and retinal cones, as it represses Lhx2 translation.
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Affiliation(s)
- Rikako Sanuki
- Department of Developmental Biology, Osaka Bioscience Institute, Suita, Osaka, Japan
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30
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Vralsted VC, Price MP, Du J, Schnizler M, Wunsch AM, Ziemann AE, Welsh MJ, Wemmie JA. Expressing acid-sensing ion channel 3 in the brain alters acid-evoked currents and impairs fear conditioning. GENES BRAIN AND BEHAVIOR 2011; 10:444-50. [PMID: 21324060 PMCID: PMC3107921 DOI: 10.1111/j.1601-183x.2011.00683.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Previous studies on mice with a disruption of the gene encoding acid-sensing ion channel 1a (ASIC1a) suggest that ASIC1a is required for normal fear behavior. To investigate the effects of altering the subunit composition of brain ASICs on behavior, we developed transgenic mice expressing ASIC3 via the pan-neuronal synapsin I promoter. These mice express ASIC3 in the brain, where the endogenous ASIC3 protein is not detected. We found that in ASIC3 transgenic mice, ASIC3 co-immunoprecipitated with the endogenous ASIC1a protein and distributed in the same subcellular brain fractions as ASIC1a. In addition, ASIC3 significantly increased the rate of desensitization of acid-evoked currents in cultured cortical neurons. Importantly, ASIC3 reduced Pavlovian fear conditioning to both context and auditory cues. These observations suggest that ASIC3 can heteromultimerize with ASIC1a in the brain and alter the biophysical properties of the endogenous channel complex. Moreover, these data suggest that ASIC subunit composition and channel desensitization may be critical determinants for ASIC-dependent behavior.
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Affiliation(s)
- V C Vralsted
- Interdisciplinary Graduate Program in Neuroscience, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
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31
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Abstract
Using the basic principles of molecular biology and laboratory techniques presented in this chapter, researchers should be able to create a wide variety of AAV vectors for both clinical and basic research applications. Basic vector design concepts are covered for both protein coding gene expression and small non-coding RNA gene expression cassettes. AAV plasmid vector backbones (available via AddGene) are described, along with critical sequence details for a variety of modular expression components that can be inserted as needed for specific applications. Protocols are provided for assembling the various DNA components into AAV vector plasmids in Escherichia coli, as well as for transferring these vector sequences into baculovirus genomes for large-scale production of AAV in the insect cell production system.
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Affiliation(s)
- John T Gray
- Department of Hematology, St. Jude Children's Research Hospital, Memphis, TN, USA.
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32
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Zhang GR, Li X, Cao H, Zhao H, Geller AI. The vesicular glutamate transporter-1 upstream promoter and first intron each support glutamatergic-specific expression in rat postrhinal cortex. Brain Res 2010; 1377:1-12. [PMID: 21172319 DOI: 10.1016/j.brainres.2010.12.040] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2010] [Revised: 10/28/2010] [Accepted: 12/13/2010] [Indexed: 12/26/2022]
Abstract
Multiple applications of direct gene transfer into neurons require restricting expression to glutamatergic neurons, or specific subclasses of glutamatergic neurons. Thus, it is desirable to develop and analyze promoters that support glutamatergic-specific expression. The three vesicular glutamate transporters (VGLUTs) are found in different populations of neurons, and VGLUT1 is the predominant VGLUT in the neocortex, hippocampus, and cerebellar cortex. We previously reported on a plasmid (amplicon) Herpes Simplex Virus vector that contains a VGLUT1 promoter. This vector supports long-term expression in VGLUT1-containing glutamatergic neurons in rat postrhinal (POR) cortex, but does not support expression in VGLUT2-containing glutamatergic neurons in the ventral medial hypothalamus. This VGLUT1 promoter contains both the VGLUT1 upstream promoter and the VGLUT1 first intron. In this study, we begin to isolate and analyze the glutamatergic-specific regulatory elements in this VGLUT1 promoter. We show that the VGLUT1 upstream promoter and first intron each support glutamatergic-specific expression. We isolated a small, basal VGLUT1 promoter that does not support glutamatergic-specific expression. Next, we fused either the VGLUT1 upstream promoter or the first intron to this basal promoter. The VGLUT1 upstream promoter or the first intron, fused to the basal promoter, each supported glutamatergic-specific expression in POR cortex.
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Affiliation(s)
- Guo-rong Zhang
- Department of Neurology, West Roxbury VA Hospital/Harvard Medical School, W. Roxbury, MA 02132, USA
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A transgenic rat model of Alzheimer's disease with extracellular Aβ deposition. Neurobiol Aging 2009; 30:1078-90. [DOI: 10.1016/j.neurobiolaging.2007.10.006] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2007] [Revised: 09/24/2007] [Accepted: 10/13/2007] [Indexed: 11/22/2022]
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Wang Y, Greenwood JSF, Calcagnotto ME, Kirsch HE, Barbaro NM, Baraban SC. Neocortical hyperexcitability in a human case of tuberous sclerosis complex and mice lacking neuronal expression of TSC1. Ann Neurol 2007; 61:139-52. [PMID: 17279540 DOI: 10.1002/ana.21058] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE To identify brain regions, cell types, or both that generate abnormal electrical discharge in tuberous sclerosis complex (TSC). Here we examined excitatory and inhibitory synaptic currents in human tissue samples obtained from a TSC patient with no discernible cortical tubers and acute neocortical brain slices from a mouse featuring synapsin-driven conditional deletion of a TSC1 gene. These studies were designed to assess whether TSC gene inactivation alters excitability. METHODS We used visualized patch-clamp (human and mouse) and extracellular field (mouse) recordings. Additional mice were processed for immunohistochemistry or Western blot analysis. RESULTS Detailed anatomic studies in brain tissue sections from synapsin-TSC1 conditional knock-out mice failed to uncover gross anatomic defects, loss of lamination, or frank tuber formation. However, regions of abnormal and potentially activated neocortex were shown using antibodies to nonphosphorylated neurofilaments (SMI-311) and immediate early genes (c-Fos). Extracellular recordings from neocortical slices, examining synaptic activity in these regions, demonstrated clear differences in excitability between conditional knock-out and age-matched control mice. Whole-cell patch-clamp recordings demonstrated excitatory synaptic currents with strikingly long duration and epileptiform discharge patterns, similar to waveforms observed in our human tissue samples. These events were 1-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) receptor mediated and were most prominent in neocortex. Normal-appearing inhibitory postsynaptic currents (human) and intrinsic neuronal firing patterns (mouse) were also recorded. INTERPRETATION This combination of human and mouse tissue studies suggests, for the first time, that synaptic excitation is altered in a direction that favors seizure generation in TSC brain tissue regardless of cortical tubers.
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Affiliation(s)
- Yanling Wang
- Department of Neurological Surgery, University of California, San Francisco, San Francisco, CA 94143, USA
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Rempe D, Vangeison G, Hamilton J, Li Y, Jepson M, Federoff HJ. Synapsin I Cre transgene expression in male mice produces germline recombination in progeny. Genesis 2006; 44:44-9. [PMID: 16419044 DOI: 10.1002/gene.20183] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The cre/LoxP system can produce conditional loss of gene function in specific cell types such as neurons. A transgenic mouse line, utilized by multiple studies, used the Synapsin I promoter to drive expression of cre (SynCre) to achieve neuronal-specific cre expression. Herein we describe that cre expression can also be observed in SynCre mice within the testes after being bred into a floxed transgenic mouse line. Cre transcript was expressed in testes resulting in recombination of the floxed substrate in testes. In the majority of cases, progeny of male SynCre mice inherited a germline recombined floxed allele, while this was never observed in progeny from female mice carrying the SynCre allele. This observation should alert investigators to a potential confound using these mice and enables male germ cell "deletor" strategies.
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de Luca C, Kowalski TJ, Zhang Y, Elmquist JK, Lee C, Kilimann MW, Ludwig T, Liu SM, Chua SC. Complete rescue of obesity, diabetes, and infertility in db/db mice by neuron-specific LEPR-B transgenes. J Clin Invest 2005; 115:3484-93. [PMID: 16284652 PMCID: PMC1280964 DOI: 10.1172/jci24059] [Citation(s) in RCA: 280] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2004] [Accepted: 09/06/2005] [Indexed: 01/09/2023] Open
Abstract
We have generated mice that carry a neuron-specific leptin receptor (LEPR) transgene whose expression is driven by the rat synapsin I promoter synapsin-LEPR B (SYN-LEPR-B). We have also generated mice that are compound hemizygotes for the transgenes SYN-LEPR-B and neuron-specific enolase-LEPR B (NSE-LEPR-B). We observed a degree of correction in db/db mice that are hemizygous (Syn db/db) and homozygous (Syn/Syn db/db) for the SYN-LEPR-B transgene similar to that previously reported for the NSE-LEPR-B transgene. We also show complete correction of the obesity and related phenotypes of db/db mice that are hemizygous for both NSE-LEPR-B and SYN-LEPR-B transgenes (Nse+Syn db/db). Body composition, insulin sensitivity, and cold tolerance were completely normalized in Nse+Syn db/db mice at 12 weeks of age compared with lean controls. In situ hybridization for LEPR B isoform expression in Nse+Syn db/db mice showed robust expression in the energy homeostasis-relevant regions of the hypothalamus. Expression of 3 neuropeptide genes, agouti-related peptide (Agrp), neuropeptide Y (Npy), and proopiomelanocortin (Pomc), was fully normalized in dual transgenic db/db mice. The 2 transgenes in concert conferred normal fertility to male and female db/db mice. Male mice with partial peripheral deletion of Lepr, induced in the periweaning phase, did not show alterations in body composition or mass. In summary, we show that brain-specific leptin signaling is sufficient to reverse the obesity, diabetes, and infertility of db/db mice.
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Affiliation(s)
- Carl de Luca
- Department of Medicine, Division of Preventative Medicine, Columbia University, New York, New York, USA
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Nakagawa T, Feliu-Mojer MI, Wulf P, Lois C, Sheng M, Hoogenraad CC. Generation of lentiviral transgenic rats expressing glutamate receptor interacting protein 1 (GRIP1) in brain, spinal cord and testis. J Neurosci Methods 2005; 152:1-9. [PMID: 16157387 DOI: 10.1016/j.jneumeth.2005.08.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2005] [Revised: 07/23/2005] [Accepted: 08/03/2005] [Indexed: 10/25/2022]
Abstract
In neuroscience, rats have several advantages over mice as a model organism. For instance, behavioral experiments are more advanced and the larger size of the brain is better suited for surgical manipulation and biochemistry. Furthermore, the vascular physiology of rats is considered closer to human, providing clinical relevance. Because transgenesis rates achieved by conventional pronuclear injection are extremely low (0.2-3.5%), the availability of transgenic rats in neuroscience is limited. Lentivirus infection is an efficient way to integrate exogenous genes into the genome of a one-cell embryo to generate transgenic animals. We report here the generation of synapsin I promoter driven GRIP1-transgenic rats using lentiviral transgenesis. GRIP1 was chosen as a transgene because it interacts with AMPA receptors and is involved in glutamate receptor signaling. From a single infection experiment, 45% of the offspring carried the transgene and 40% achieved germ-line transmission. The expression of GRIP1 was observed at low levels in brain, spinal cord and testis. Interestingly, one transgenic copy lacked a 147 bp fragment in the GRIP1 coding region most likely caused by alternative splicing of genomic lentiviral RNA. Co-immunoprecipitation from rat brains showed that transgenic GRIP1 is in complex with the endogenous GluR2 subunit of AMPA receptors. These results indicate that functional transgenic GRIP1 protein is expressed in rat brain using lentiviral vectors containing a human synapsin I promoter. Tissue specific lentiviral transgenic rats will be a powerful tool for various applications in modern neuroscience.
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Affiliation(s)
- Terunaga Nakagawa
- The Picower Center for Learning and Memory, RIKEN-MIT Neuroscience Research Center, Massachusetts Institute of Technology, 77 Massachusetts Avenue (E18-215), Cambridge, MA 02139, USA
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Street KA, Xu G, Hall KL, Intano GW, McCarrey JR, Herbert DC, Kilimann MW, Walter CA. Rat Synapsin 1 Promoter Mediated Transgene Expression in Testicular Cell Types. DNA Cell Biol 2005; 24:133-40. [PMID: 15699633 DOI: 10.1089/dna.2005.24.133] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Previous reports described the rat synapsin 1 promoter as primarily neuron selective. However, ectopic expression of a transgene under the rat synapsin 1 promoter was also detected in testis from some transgenic mouse lines. Here we investigate which cells within the testis express a transgene consisting of the rat synapsin 1 promoter fused with luciferase. Synapsin 1-luciferase expression vectors were introduced into HeLa cells, into TM3 cells derived from mouse testicular Leydig cells, and into one-cell embryos to make transgenic mice. Indirect immunofluorescence suggests that nontransfected TM3 cells do not express endogenous synapsin 1. TM3 stable transfectants, however, expressed luciferase under the direction of the synapsin 1 promoter, in both promoter orientations. HeLa cells displayed only low levels of activity. Transgenic mice carrying the synapsin 1-luciferase construct displayed high levels of luciferase activity in the brain, spinal cord, and testis. Enriched populations of prepuberal types A and B spermatogonia and adult Leydig cells, pachytene spermatocytes, and round spermatids prepared from transgenic mice all displayed substantial luciferase activity. Thus, the rat synapsin 1 promoter can mediate reporter gene expression in neurons and testicular cell types.
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Affiliation(s)
- K A Street
- Department of Cellular & Structural Biology, the University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229-3900, USA
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Hasue F, Kuwaki T, Kisanuki YY, Yanagisawa M, Moriya H, Fukuda Y, Shimoyama M. Increased sensitivity to acute and persistent pain in neuron-specific endothelin-1 knockout mice. Neuroscience 2005; 130:349-58. [PMID: 15664691 DOI: 10.1016/j.neuroscience.2004.09.036] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/21/2004] [Indexed: 01/23/2023]
Abstract
Endothelin-1 (ET-1) exists in endothelial cells as well as a variety of other cell types. The presence of ET-1 and its receptors in neurons suggests its possible role as a neurotransmitter and/or neuromodulator. Studies utilizing exogenous ET-1 have suggested that ET-1 affects pain transmission. This study was designed to examine the possible role(s) of neuronal ET-1 in pain processing. We produced neuron-specific ET-1 knockout mice using the Cre/loxP system with a synapsin I promoter and examined the effects produced by the lack of neuronal ET-1 on pain behavior using common pain models and a model of stress-induced analgesia. In acute nociceptive pain models, paw withdrawal thresholds to radiant heat and mechanical stimuli applied with von Frey hairs were significantly lower in the knockout mice compared with control. This indicated that the absence of neuronal ET-1 leads to greater sensitivity to acute nociceptive stimuli. After inflammation was produced by intraplantar injection of carrageenan, there was a significantly greater degree of thermal hyperalgesia and mechanical allodynia in the knockout mice even after the difference in baseline values was compensated. Furthermore, in a neuropathic pain model produced by spinal nerve ligation, there was also a greater degree of mechanical allodynia in the knockout mice. Finally, in a swim-stress model, the magnitude of stress-induced analgesia was less in the knockout mice, indicating the involvement of neuronal ET-1 in stress-induced analgesia. The results suggest that there is a basal release of ET-1 from neurons that affect baseline pain thresholds as well as an additional release during persistent pain states that acts to suppress the pain. The involvement of neuronal ET-1 in stress-induced analgesia further suggests its role in endogenous pain inhibitory systems. To confirm that ET-1 is released in persistent pain states and to determine which part of the CNS is involved, we measured the concentrations of ET-1 before and after inducing peripheral inflammation in different parts of the CNS involved in endogenous pain inhibitory systems in normal mice. We found that ET-1 was increased in the hypothalamus while no significant increase was observed in the midbrain, medulla and spinal cord. The results of the present study suggest that neuronal ET-1 is involved in endogenous pain inhibitory control likely via pathways through the hypothalamus.
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Affiliation(s)
- F Hasue
- Department of Autonomic Physiology, 1-8-1, Nohana, Chuo-ku, Chiba-shi, Chiba 260-8670, Japan
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Dittgen T, Nimmerjahn A, Komai S, Licznerski P, Waters J, Margrie TW, Helmchen F, Denk W, Brecht M, Osten P. Lentivirus-based genetic manipulations of cortical neurons and their optical and electrophysiological monitoring in vivo. Proc Natl Acad Sci U S A 2004; 101:18206-11. [PMID: 15608064 PMCID: PMC539748 DOI: 10.1073/pnas.0407976101] [Citation(s) in RCA: 393] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
It is becoming increasingly clear that single cortical neurons encode complex and behaviorally relevant signals, but efficient means to study gene functions in small networks and single neurons in vivo are still lacking. Here, we establish a method for genetic manipulation and subsequent phenotypic analysis of individual cortical neurons in vivo. First, lentiviral vectors are used for neuron-specific gene delivery from alpha-calcium/calmodulin-dependent protein kinase II or Synapsin I promoters, optionally in combination with gene knockdown by means of U6 promoter-driven expression of short-interfering RNAs. Second, the phenotypic analysis at the level of single cortical cells is carried out by using two-photon microscopy-based techniques: high-resolution two-photon time-lapse imaging is used to monitor structural dynamics of dendritic spines and axonal projections, whereas cellular response properties are analyzed electrophysiologically by two-photon microscopy directed whole-cell recordings. This approach is ideally suited for analysis of gene functions in individual neurons in the intact brain.
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Affiliation(s)
- Tanjew Dittgen
- Department of Molecular Neurobiology, Max Planck Institute for Medical Research, Jahnstrasse 29, 69120 Heidelberg, Germany
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Wemmie JA, Coryell MW, Askwith CC, Lamani E, Leonard AS, Sigmund CD, Welsh MJ. Overexpression of acid-sensing ion channel 1a in transgenic mice increases acquired fear-related behavior. Proc Natl Acad Sci U S A 2004; 101:3621-6. [PMID: 14988500 PMCID: PMC373512 DOI: 10.1073/pnas.0308753101] [Citation(s) in RCA: 156] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The acid-sensing ion channel 1a (ASIC1a) is abundantly expressed in the amygdala complex and other brain regions associated with fear. Studies of mice with a disrupted ASIC1 gene suggested that ASIC1a may contribute to learned fear. To test this hypothesis, we generated mice overexpressing human ASIC1a by using the pan-neuronal synapsin 1 promoter. Transgenic ASIC1a interacted with endogenous mouse ASIC1a and was distributed to the synaptosomal fraction of brain. Transgenic expression of ASIC1a also doubled neuronal acid-evoked cation currents. The amygdala showed prominent expression, and overexpressing ASIC1a enhanced fear conditioning, an animal model of acquired anxiety. These data raise the possibility that ASIC1a and H(+)-gated currents may contribute to the development of abnormal fear and to anxiety disorders in humans.
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Affiliation(s)
- John A Wemmie
- Department of Psychiatry, Howard Hughes Medical Institute, University of Iowa, Iowa City, IA 52242, USA
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Xia CH, Roberts EA, Her LS, Liu X, Williams DS, Cleveland DW, Goldstein LSB. Abnormal neurofilament transport caused by targeted disruption of neuronal kinesin heavy chain KIF5A. J Cell Biol 2003; 161:55-66. [PMID: 12682084 PMCID: PMC2172877 DOI: 10.1083/jcb.200301026] [Citation(s) in RCA: 252] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
To test the hypothesis that fast anterograde molecular motor proteins power the slow axonal transport of neurofilaments (NFs), we used homologous recombination to generate mice lacking the neuronal-specific conventional kinesin heavy chain, KIF5A. Because null KIF5A mutants die immediately after birth, a synapsin-promoted Cre-recombinase transgene was used to direct inactivation of KIF5A in neurons postnatally. Three fourths of such mutant mice exhibited seizures and death at around 3 wk of age; the remaining animals survived to 3 mo or longer. In young mutant animals, fast axonal transport appeared to be intact, but NF-H, as well as NF-M and NF-L, accumulated in the cell bodies of peripheral sensory neurons accompanied by a reduction in sensory axon caliber. Older animals also developed age-dependent sensory neuron degeneration, an accumulation of NF subunits in cell bodies and a reduction in axons, loss of large caliber axons, and hind limb paralysis. These data support the hypothesis that a conventional kinesin plays a role in the microtubule-dependent slow axonal transport of at least one cargo, the NF proteins.
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Affiliation(s)
- Chun-Hong Xia
- Department of Cellular and Molecular Medicine, Howard Hughes Medical Institute, University of California, San Diego, La Jolla, CA 92093-0683, USA
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Morimoto S, Cassell MD, Sigmund CD. Glia- and neuron-specific expression of the renin-angiotensin system in brain alters blood pressure, water intake, and salt preference. J Biol Chem 2002; 277:33235-41. [PMID: 12080069 DOI: 10.1074/jbc.m204309200] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The purpose of this study is to examine the regulation of blood pressure and fluid and electrolyte homeostasis in mice overexpressing angiotensin II (Ang-II) in the brain and to determine whether there are significant physiologic differences in Ang-II production in neurons or glia. Therefore, we generated and characterized transgenic mice overexpressing human renin (hREN) under the control of the glial fibrillary acidic protein (GFAP) promoter (GFAP-hREN) and synapsin-I promoter (SYN-hREN) and bred them with mice expressing human angiotensinogen (hAGT) under the control of the same promoters (GFAP-hAGT and SYN-hAGT). Both GFAP-hREN and SYN-hREN mice exhibited the highest hREN mRNA expression in the brain and had undetectable levels of hREN protein in the systemic circulation. In the brain of GFAP-hREN and SYN-hREN mice, hREN protein was observed almost exclusively in astrocytes and neurons, respectively. Transgenic mice overexpressing both hREN and hAGT transgenes in either glia or neurons were moderately hypertensive. In the glia-targeted mice, blood pressure could be corrected by intracerebroventricular injection of the Ang-II type 1 receptor antagonist losartan, and intravenous injection of a ganglion blocking agent, but not an arginine vasopressin V1 receptor antagonist, lowered blood pressure. These data suggest that stimulation of Ang-II type 1 receptors in the brain by Ang-II derived from local synthesis of renin and angiotensinogen can cause an elevation in blood pressure via a mechanism involving enhanced sympathetic outflow. Glia- and neuron-targeted mice also exhibited an increase in drinking volume and salt preference, suggesting that chronic overexpression of renin and angiotensinogen locally in the brain can result in hypertension and alterations in fluid homeostasis.
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Affiliation(s)
- Satoshi Morimoto
- Department of Internal Medicine and Physiology & Biophysics, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa 52242, USA
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Morimoto S, Cassell MD, Sigmund CD. Neuron-specific expression of human angiotensinogen in brain causes increased salt appetite. Physiol Genomics 2002; 9:113-20. [PMID: 12006677 DOI: 10.1152/physiolgenomics.00007.2002] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The brain renin-angiotensin system (RAS) has an important role in the regulation of cardiovascular function. In the brain, angiotensinogen (AGT) is expressed mainly in astrocytes (glia) and in some neurons in regions controlling cardiovascular activities. Because of the inability to dissect the functional role of astrocyte- vs. neuron-derived AGT in vivo by pharmacological approaches, the exact role of neuron-derived AGT in the regulation of blood pressure (BP) and fluid and electrolyte balance remains unclear. Therefore, we generated a transgenic mouse model overexpressing human AGT under the control of a neuron-specific (synapsin I) promoter (SYN-hAGT). These mice exhibited high-level expression of human AGT mRNA in the brain, with lower expression in the kidney and heart. Human AGT was not detected in plasma, but in the brain it was expressed exclusively in neurons. Intracerebroventricular (30 ng) but not intravenous (500 ng) injection of purified human renin (hREN) caused a pressor response, which was prevented by intracerebroventricular preinjection of the angiotensin II type 1 receptor antagonist losartan, indicating an AT(1) receptor-dependent functional role of neuron-derived AGT in the regulation of BP in response to exogenous REN. Double transgenic mice expressing both the hREN gene and SYN-hAGT transgene exhibited normal BP and water intake but had an increased preference for salt. These data suggest that neuronal AGT may play an important role in regulating salt intake and salt appetite.
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Affiliation(s)
- Satoshi Morimoto
- Department of Internal Medicine, University of Iowa College of Medicine, Iowa City, Iowa 52242, USA
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Findlay GS, Wick MJ, Mascia MP, Wallace D, Miller GW, Harris RA, Blednov YA. Transgenic expression of a mutant glycine receptor decreases alcohol sensitivity of mice. J Pharmacol Exp Ther 2002; 300:526-34. [PMID: 11805213 DOI: 10.1124/jpet.300.2.526] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Glycine receptors (GlyRs) are pentameric ligand-gated ion channels that inhibit neurotransmission in the adult brainstem and spinal cord. GlyR function is potentiated by ethanol in vitro, and a mutant GlyR subunit alpha(1)(S267Q) is insensitive to the potentiating effects of ethanol. To test the importance of GlyR for the actions of ethanol in vivo, we constructed transgenic mice with this mutation. Under the control of synapsin I regulatory sequences, transgenic expression of S267Q mutant GlyR alpha(1) subunits in the nervous system was demonstrated using [(3)H]strychnine binding and immunoblotting. These mice showed decreased sensitivity to ethanol in three behavioral tests: ethanol inhibition of strychnine seizures, motor incoordination (rotarod), and loss of righting reflex. There was no change in ethanol sensitivity in tests of acute functional tolerance or body temperature, and there was no change in ethanol metabolism. Transgene effects were pharmacologically specific for ethanol, compared with pentobarbital, flurazepam, and ketamine. These results support the idea that glycine receptors contribute to some behavioral actions of ethanol and that ethanol sensitivity can be changed in vivo by transgenic expression of a single receptor subunit.
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Affiliation(s)
- G S Findlay
- Waggoner Center for Alcohol and Addiction Research, Section of Neurobiology, University of Texas at Austin, 78712, USA.
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Holzer M, Gärtner U, Klinz FJ, Narz F, Heumann R, Arendt T. Activation of mitogen-activated protein kinase cascade and phosphorylation of cytoskeletal proteins after neurone-specific activation of p21ras. I. Mitogen-activated protein kinase cascade. Neuroscience 2002; 105:1031-40. [PMID: 11530240 DOI: 10.1016/s0306-4522(01)00245-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Alterations in the phosphorylation state of the microtubule-associated protein tau have been associated with the pathogenesis of neurofibrillary degeneration as well as with a neuroprotective action against apoptotic cell death. Mitogen-activated protein kinases (MAPK) phosphorylate tau protein in vitro but the pathophysiological significance of this tau phosphorylation and its effects on neuronal viability is far from clear. Moreover, an in vivo model of activation of MAPK, a key candidate for in vivo tau phosphorylation, is still lacking. The aim of the present study and the accompanying paper was to establish an animal model of stimulated MAPK and to analyse the consequences on tau phosphorylation and the neuronal cytoskeleton. We took advantage of transgenic mice with neurone-specific expression of activated ras protein (p21H-ras(Val12)). The expression of the transgene in these animals is forced to a subset of neurones by the use of the synapsin I promoter. Activity of B-raf was elevated by 37%, while activity of MAPK (ERK1/ERK2) was increased by 25% associated with a subcellular redistribution from the cytoplasmic to the nuclear compartment. Kinases downstream of MAPK such as p90rsk and glycogen synthase kinase 3beta were only marginally affected. Activity of p70S6 kinase was unaltered. The present model might be useful to study the effects of activation of the MAPK cascade on tau phosphorylation and its cell biological sequelae.
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Affiliation(s)
- M Holzer
- Paul Flechsig Institute of Brain Research, Department of Neuroanatomy, University of Leipzig, Germany.
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Cohen P, Zhao C, Cai X, Montez JM, Rohani SC, Feinstein P, Mombaerts P, Friedman JM. Selective deletion of leptin receptor in neurons leads to obesity. J Clin Invest 2001. [PMID: 11602618 DOI: 10.1172/jci200113914] [Citation(s) in RCA: 401] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Animals with mutations in the leptin receptor (ObR) exhibit an obese phenotype that is indistinguishable from that of leptin deficient ob/ob mice. ObR is expressed in many tissues, including brain, and the relative importance of leptin's effects on central versus peripheral sites has not been resolved. To address this, we generated mice with neuron-specific (ObR(SynI)KO) and hepatocyte-specific (ObR(Alb)KO) disruption of ObR. Among the ObR(SynI)KO mice, the extent of obesity was negatively correlated with the level of ObR in hypothalamus and those animals with the lowest levels of ObR exhibited an obese phenotype. The obese mice with low levels of hypothalamic ObR also show elevated plasma levels of leptin, glucose, insulin, and corticosterone. The hypothalamic levels of agouti-related protein and neuropeptide Y RNA are increased in these mice. These data indicate that leptin has direct effects on neurons and that a significant proportion, or perhaps the majority, of its weight-reducing effects are the result of its actions on brain. To explore possible direct effects of leptin on a peripheral tissue, we also characterized ObR(Alb)KO mice. These mice weigh the same as controls and have no alterations in body composition. Moreover, while db/db mice and ObR(SynI)KO mice have enlarged fatty livers, ObR(Alb)KO mice do not. In summary, these data suggest that the brain is a direct target for the weight-reducing and neuroendocrine effects of leptin and that the liver abnormalities of db/db mice are secondary to defective leptin signaling in the brain.
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Affiliation(s)
- P Cohen
- Laboratory of Molecular Genetics, The Rockefeller University, 1230 York Avenue, New York, NY 10021, USA
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48
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Sigmund CD. Genetic manipulation of the renin-angiotensin system in the kidney. ACTA PHYSIOLOGICA SCANDINAVICA 2001; 173:67-73. [PMID: 11678728 DOI: 10.1046/j.1365-201x.2001.00886.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Over the past 5 years, genetic manipulation has revolutionized the way we examine physiological processes by providing a targeted specificity that was not possible previously. The application of transgenesis and gene targeting has been applied to numerous physiological pathways; and both will remain important tools as we reach the completion of the human genome project and begin to assess the function of newly identified genes. The renin-angiotensin system (RAS) has been the target of numerous transgenic and gene targeting studies designed to help uncover its role in cardiovascular regulation and organ development. Each gene of the system has now been both over-expressed and knocked out. It will be discussed as to how new advances in tissue-specific gene targeting by both over-expression and gene ablation can be used as powerful tools to dissect the role of the RAS in individual tissues.
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Affiliation(s)
- C D Sigmund
- Department of Internal Medicine and Physiology & Biophysics, The University of Iowa College of Medicine, Iowa City, IA 52242, USA
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49
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Wells T, Carter DA. Genetic engineering of neural function in transgenic rodents: towards a comprehensive strategy? J Neurosci Methods 2001; 108:111-30. [PMID: 11478971 DOI: 10.1016/s0165-0270(01)00391-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
As mammalian genome projects move towards completion, the attention of molecular neuroscientists is currently moving away from gene identification towards both cell-specific gene expression patterns (neuronal transcriptions) and protein expression/interactions (neuronal proteomics). In the long term, attention will increasingly be directed towards experimental interventions which are able to question neuronal function in a sophisticated manner that is cognisant of both transcriptomic and proteomic organization. Central to this effort will be the application of a new generation of transgenic approaches which are now evolving towards an appropriate level of molecular, temporal and spatial resolution. In this review, we summarize recent developments in transgenesis, and show how they have been applied in the principal model species for neuroscience, namely rats and mice. Current concepts of transgene design are also considered together with an overview of new genetically-encoded tools including both cellular indicators such as fluorescent activity reporters, and cellular regulators such as dominant negative signalling factors. Application of these tools in a whole animal context can be used to question both basic concepts of brain function, and also current concepts of underlying dysfuction in neurological diseases.
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Affiliation(s)
- T Wells
- School of Biosciences, Cardiff University, PO Box 911, Museum Avenue, Cardiff CF10 3US, UK
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50
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Zhu Y, Romero MI, Ghosh P, Ye Z, Charnay P, Rushing EJ, Marth JD, Parada LF. Ablation of NF1 function in neurons induces abnormal development of cerebral cortex and reactive gliosis in the brain. Genes Dev 2001; 15:859-76. [PMID: 11297510 PMCID: PMC312666 DOI: 10.1101/gad.862101] [Citation(s) in RCA: 448] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Neurofibromatosis type 1 (NF1) is a prevalent genetic disorder that affects growth properties of neural-crest-derived cell populations. In addition, approximately one-half of NF1 patients exhibit learning disabilities. To characterize NF1 function both in vitro and in vivo, we circumvent the embryonic lethality of NF1 null mouse embryos by generating a conditional mutation in the NF1 gene using Cre/loxP technology. Introduction of a Synapsin I promoter driven Cre transgenic mouse strain into the conditional NF1 background has ablated NF1 function in most differentiated neuronal populations. These mice have abnormal development of the cerebral cortex, which suggests that NF1 has an indispensable role in this aspect of CNS development. Furthermore, although they are tumor free, these mice display extensive astrogliosis in the absence of conspicuous neurodegeneration or microgliosis. These results indicate that NF1-deficient neurons are capable of inducing reactive astrogliosis via a non-cell autonomous mechanism.
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MESH Headings
- Alleles
- Animals
- Cell Transformation, Neoplastic/genetics
- Cells, Cultured
- Cerebral Cortex/abnormalities
- Cerebral Cortex/embryology
- Disease Models, Animal
- Ganglia, Spinal/pathology
- Gene Expression Regulation, Developmental
- Genes, Neurofibromatosis 1
- Genes, Reporter
- Genes, Synthetic
- Genetic Vectors/genetics
- Gliosis/metabolism
- Integrases/genetics
- Integrases/physiology
- Lac Operon
- Learning Disabilities/genetics
- MAP Kinase Signaling System/genetics
- Mice
- Mice, Knockout
- Mice, Neurologic Mutants
- Mice, Transgenic
- Nerve Tissue Proteins/deficiency
- Nerve Tissue Proteins/genetics
- Nerve Tissue Proteins/physiology
- Neurofibromin 1
- Neurons/metabolism
- Promoter Regions, Genetic
- Proto-Oncogene Proteins p21(ras)/physiology
- Recombinant Fusion Proteins/biosynthesis
- Recombinant Fusion Proteins/genetics
- Recombinant Fusion Proteins/physiology
- Signal Transduction
- Synapsins/genetics
- Viral Proteins
- p120 GTPase Activating Protein/genetics
- p120 GTPase Activating Protein/physiology
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Affiliation(s)
- Y Zhu
- Center for Developmental Biology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9133, USA
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