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Sumser A, Joesch M, Jonas P, Ben-Simon Y. Fast, high-throughput production of improved rabies viral vectors for specific, efficient and versatile transsynaptic retrograde labeling. eLife 2022; 11:79848. [PMID: 36040301 PMCID: PMC9477495 DOI: 10.7554/elife.79848] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Accepted: 08/29/2022] [Indexed: 11/13/2022] Open
Abstract
To understand the function of neuronal circuits, it is crucial to disentangle the connectivity patterns within the network. However, most tools currently used to explore connectivity have low throughput, low selectivity, or limited accessibility. Here, we report the development of an improved packaging system for the production of the highly neurotropic RVdGenvA-CVS-N2c rabies viral vectors, yielding titers orders of magnitude higher with no background contamination, at a fraction of the production time, while preserving the efficiency of transsynaptic labeling. Along with the production pipeline, we developed suites of ‘starter’ AAV and bicistronic RVdG-CVS-N2c vectors, enabling retrograde labeling from a wide range of neuronal populations, tailored for diverse experimental requirements. We demonstrate the power and flexibility of the new system by uncovering hidden local and distal inhibitory connections in the mouse hippocampal formation and by imaging the functional properties of a cortical microcircuit across weeks. Our novel production pipeline provides a convenient approach to generate new rabies vectors, while our toolkit flexibly and efficiently expands the current capacity to label, manipulate and image the neuronal activity of interconnected neuronal circuits in vitro and in vivo.
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Affiliation(s)
- Anton Sumser
- Institute of Science and Technology Austria, Klosterneuburg, Austria
| | - Maximilian Joesch
- Institute of Science and Technology Austria, Klosterneuburg, Austria
| | - Peter Jonas
- Institute of Science and Technology Austria, Klosterneuburg, Austria
| | - Yoav Ben-Simon
- Department of Neurophysiology and Neuropharmacology, Vienna Medical University, Vienna, Austria
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2
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Mesodiencephalic junction GABAergic inputs are processed separately from motor cortical inputs in the basilar pons. iScience 2022; 25:104641. [PMID: 35800775 PMCID: PMC9254490 DOI: 10.1016/j.isci.2022.104641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 04/13/2022] [Accepted: 06/14/2022] [Indexed: 11/21/2022] Open
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Deng L, Ravenscraft B, Xu XM. Exploring propriospinal neuron-mediated neural circuit plasticity using recombinant viruses after spinal cord injury. Exp Neurol 2021; 349:113962. [PMID: 34953895 DOI: 10.1016/j.expneurol.2021.113962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 12/16/2021] [Accepted: 12/19/2021] [Indexed: 11/04/2022]
Abstract
Propriospinal neurons (PSNs) play a crucial role in motor control and sensory processing and contribute to plastic reorganization of spinal circuits responsible for recovery from spinal cord injury (SCI). Due to their scattered distribution and various intersegmental projection patterns, it is challenging to dissect the function of PSNs within the neuronal network. New genetically encoded tools, particularly cell-type-specific transgene expression methods using recombinant viral vectors combined with other genetic, pharmacologic, and optogenetic approaches, have enormous potential for visualizing PSNs in the neuronal circuits and monitoring and manipulating their activity. Furthermore, recombinant viral tools have been utilized to promote the intrinsic regenerative capacities of PSNs, towards manipulating the 'hostile' microenvironment for improving functional regeneration of PSNs. Here we summarize the latest development in this fast-moving field and provide a perspective for using this technology to dissect PSN physiological role in contributing to recovery of function after SCI.
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Affiliation(s)
- Lingxiao Deng
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN 46202, United States; Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, United States
| | - Baylen Ravenscraft
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN 46202, United States
| | - Xiao-Ming Xu
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN 46202, United States; Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, United States.
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4
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Götz M, Bocchi R. Neuronal replacement: Concepts, achievements, and call for caution. Curr Opin Neurobiol 2021; 69:185-192. [PMID: 33984604 PMCID: PMC8411662 DOI: 10.1016/j.conb.2021.03.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 03/21/2021] [Accepted: 03/23/2021] [Indexed: 02/01/2023]
Abstract
Regenerative approaches have made such a great progress, now aiming toward replacing the exact neurons lost upon injury or neurodegeneration. Transplantation and direct reprogramming approaches benefit from identification of molecular programs for neuronal subtype specification, allowing engineering of more precise neuronal subtypes. Disentangling subtype diversity from dynamic transcriptional states presents a challenge now. Adequate identity and connectivity is a prerequisite to restore neuronal network function, which is achieved by transplanted neurons generating the correct output and input, depending on the location and injury condition. Direct neuronal reprogramming of local glial cells has also made great progress in achieving high efficiency of conversion, with adequate output connectivity now aiming toward the goal of replacing neurons in a noninvasive approach.
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Affiliation(s)
- Magdalena Götz
- Physiological Genomics, Biomedical Center (BMC), Ludwig-Maximilians-Universitaet (LMU), Großhaderner Str. 9, 82152 Planegg/Martinsried, Germany; Helmholtz Center Munich, Biomedical Center (BMC), Institute of Stem Cell Research, Großhaderner Str. 9, 82152 Planegg/Martinsried, Germany; SyNergy Excellence Cluster, Munich, Germany.
| | - Riccardo Bocchi
- Physiological Genomics, Biomedical Center (BMC), Ludwig-Maximilians-Universitaet (LMU), Großhaderner Str. 9, 82152 Planegg/Martinsried, Germany; Helmholtz Center Munich, Biomedical Center (BMC), Institute of Stem Cell Research, Großhaderner Str. 9, 82152 Planegg/Martinsried, Germany.
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5
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Delineating the organization of projection neuron subsets in primary visual cortex with multiple fluorescent rabies virus tracing. Brain Struct Funct 2021; 226:951-961. [PMID: 33710409 DOI: 10.1007/s00429-021-02250-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Accepted: 03/01/2021] [Indexed: 10/21/2022]
Abstract
The impressive functions of the brain rely on an extensive connectivity matrix between specific neurons, the architecture of which is frequently characterized by one brain nucleus/region connecting to multiple targets, either via collaterals of the same projection neuron or several, differentially specified neurons. Delineating the fine architecture of projection neuron subsets in a specific brain region could greatly facilitate its circuit, computational, and functional resolution. Here, we developed multiple fluorescent rabies viruses (RV) to delineate the fine organization of corticothalamic projection neuron subsets in the primary visual cortex (V1). By simultaneously retrograde labeling multiple distinct subsets of corticothalamic projection neurons in V1 from their target nuclei in thalamus (dLGN, LP, LD), we observed that V1-dLGN corticothalamic projection neurons were densely concentrated in layer VI, except for several sparsely scattered neurons in layer V, while V1-LP and V1-LD corticothalamic projection neurons were localized to both layers V and VI. Meanwhile, we observed a fraction of V1 corticothalamic projection neurons targeting two thalamic nuclei, which was further confirmed by fMOST whole-brain imaging. The multiple fluorescent RV tracing tools can be extensively applied to resolve the architecture of projection neuron subsets in certain brain regions, with a strong potential to delineate the computational and functional organization of these brain regions.
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6
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Noguchi A, Ikegaya Y, Matsumoto N. In Vivo Whole-Cell Patch-Clamp Methods: Recent Technical Progress and Future Perspectives. SENSORS (BASEL, SWITZERLAND) 2021; 21:1448. [PMID: 33669656 PMCID: PMC7922023 DOI: 10.3390/s21041448] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 02/12/2021] [Accepted: 02/16/2021] [Indexed: 02/01/2023]
Abstract
Brain functions are fundamental for the survival of organisms, and they are supported by neural circuits consisting of a variety of neurons. To investigate the function of neurons at the single-cell level, researchers often use whole-cell patch-clamp recording techniques. These techniques enable us to record membrane potentials (including action potentials) of individual neurons of not only anesthetized but also actively behaving animals. This whole-cell recording method enables us to reveal how neuronal activities support brain function at the single-cell level. In this review, we introduce previous studies using in vivo patch-clamp recording techniques and recent findings primarily regarding neuronal activities in the hippocampus for behavioral function. We further discuss how we can bridge the gap between electrophysiology and biochemistry.
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Affiliation(s)
- Asako Noguchi
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo 113-0033, Japan; (A.N.); (Y.I.)
| | - Yuji Ikegaya
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo 113-0033, Japan; (A.N.); (Y.I.)
- Institute for AI and Beyond, The University of Tokyo, Tokyo 113-0033, Japan
- Center for Information and Neural Networks, National Institute of Information and Communications Technology, Suita City, Osaka 565-0871, Japan
| | - Nobuyoshi Matsumoto
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo 113-0033, Japan; (A.N.); (Y.I.)
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Xu X, Holmes TC, Luo MH, Beier KT, Horwitz GD, Zhao F, Zeng W, Hui M, Semler BL, Sandri-Goldin RM. Viral Vectors for Neural Circuit Mapping and Recent Advances in Trans-synaptic Anterograde Tracers. Neuron 2020; 107:1029-1047. [PMID: 32755550 DOI: 10.1016/j.neuron.2020.07.010] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Revised: 06/23/2020] [Accepted: 07/12/2020] [Indexed: 12/17/2022]
Abstract
Viral tracers are important tools for neuroanatomical mapping and genetic payload delivery. Genetically modified viruses allow for cell-type-specific targeting and overcome many limitations of non-viral tracers. Here, we summarize the viruses that have been developed for neural circuit mapping, and we provide a primer on currently applied anterograde and retrograde viral tracers with practical guidance on experimental uses. We also discuss and highlight key technical and conceptual considerations for developing new safer and more effective anterograde trans-synaptic viral vectors for neural circuit analysis in multiple species.
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Affiliation(s)
- Xiangmin Xu
- Department of Anatomy and Neurobiology, School of Medicine, University of California, Irvine, Irvine, CA 92697-1275, USA; Department of Microbiology and Molecular Genetics, School of Medicine, University of California, Irvine, Irvine, CA 92697-4025, USA; Department of Biomedical Engineering, University of California, Irvine, Irvine, CA 92697-2715, USA; The Center for Neural Circuit Mapping, University of California, Irvine, Irvine, CA 92697, USA.
| | - Todd C Holmes
- Department of Physiology and Biophysics, University of California, Irvine, Irvine, CA 92697-4560, USA; The Center for Neural Circuit Mapping, University of California, Irvine, Irvine, CA 92697, USA
| | - Min-Hua Luo
- State Key Laboratory of Virology, Wuhan Institute of Virology, CAS Center for Excellence in Brain Science, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan 430071, China; The Center for Neural Circuit Mapping, University of California, Irvine, Irvine, CA 92697, USA
| | - Kevin T Beier
- Department of Physiology and Biophysics, University of California, Irvine, Irvine, CA 92697-4560, USA; The Center for Neural Circuit Mapping, University of California, Irvine, Irvine, CA 92697, USA
| | - Gregory D Horwitz
- The Washington National Primate Research Center, University of Washington, Seattle, WA 98195, USA; Department of Physiology & Biophysics, University of Washington, Seattle, WA 98195, USA; The Center for Neural Circuit Mapping, University of California, Irvine, Irvine, CA 92697, USA
| | - Fei Zhao
- School of Basic Medical Sciences, Capital Medical University, Beijing 102206, China; Chinese Institute for Brain Research (CIBR), Beijing 102206, China
| | - Wenbo Zeng
- State Key Laboratory of Virology, Wuhan Institute of Virology, CAS Center for Excellence in Brain Science, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan 430071, China
| | - May Hui
- Department of Physiology and Biophysics, University of California, Irvine, Irvine, CA 92697-4560, USA
| | - Bert L Semler
- Department of Microbiology and Molecular Genetics, School of Medicine, University of California, Irvine, Irvine, CA 92697-4025, USA; The Center for Neural Circuit Mapping, University of California, Irvine, Irvine, CA 92697, USA
| | - Rozanne M Sandri-Goldin
- Department of Microbiology and Molecular Genetics, School of Medicine, University of California, Irvine, Irvine, CA 92697-4025, USA; The Center for Neural Circuit Mapping, University of California, Irvine, Irvine, CA 92697, USA
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8
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Cushnie AK, El-Nahal HG, Bohlen MO, May PJ, Basso MA, Grimaldi P, Wang MZ, de Velasco Ezequiel MF, Sommer MA, Heilbronner SR. Using rAAV2-retro in rhesus macaques: Promise and caveats for circuit manipulation. J Neurosci Methods 2020; 345:108859. [PMID: 32668316 DOI: 10.1016/j.jneumeth.2020.108859] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 07/01/2020] [Accepted: 07/10/2020] [Indexed: 12/21/2022]
Abstract
BACKGROUND Recent genetic technologies such as opto- and chemogenetics allow for the manipulation of brain circuits with unprecedented precision. Most studies employing these techniques have been undertaken in rodents, but a more human-homologous model for studying the brain is the nonhuman primate (NHP). Optimizing viral delivery of transgenes encoding actuator proteins could revolutionize the way we study neuronal circuits in NHPs. NEW METHOD: rAAV2-retro, a popular new capsid variant, produces robust retrograde labeling in rodents. Whether rAAV2-retro's highly efficient retrograde transport would translate to NHPs was unknown. Here, we characterized the anatomical distribution of labeling following injections of rAAV2-retro encoding opsins or DREADDs in the cortico-basal ganglia and oculomotor circuits of rhesus macaques. RESULTS rAAV2-retro injections in striatum, frontal eye field, and superior colliculus produced local labeling at injection sites and robust retrograde labeling in many afferent regions. In every case, however, a few brain regions with well-established projections to the injected structure lacked retrogradely labeled cells. We also observed robust terminal field labeling in downstream structures. COMPARISON WITH EXISTING METHOD(S) Patterns of labeling were similar to those obtained with traditional tract-tracers, except for some afferent labeling that was noticeably absent. CONCLUSIONS rAAV2-retro promises to be useful for circuit manipulation via retrograde transduction in NHPs, but caveats were revealed by our findings. Some afferently connected regions lacked retrogradely labeled cells, showed robust axon terminal labeling, or both. This highlights the importance of anatomically characterizing rAAV2-retro's expression in target circuits in NHPs before moving to manipulation studies.
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Affiliation(s)
- Adriana K Cushnie
- Department of Neuroscience, University of Minnesota, Minneapolis, MN 55455, United States
| | - Hala G El-Nahal
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, United States
| | - Martin O Bohlen
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, United States
| | - Paul J May
- Department of Neurobiology and Anatomical Sciences, University of Mississippi Medical Center, Jackson, 39216, United States
| | - Michele A Basso
- Fuster Laboratory of Cognitive Neuroscience, Department of Psychiatry and Biobehavioral Sciences and Neurobiology, Jane and Terry Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, Univ. of California Los Angeles, Los Angeles, CA 90095, United States
| | - Piercesare Grimaldi
- Fuster Laboratory of Cognitive Neuroscience, Department of Psychiatry and Biobehavioral Sciences and Neurobiology, Jane and Terry Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, Univ. of California Los Angeles, Los Angeles, CA 90095, United States
| | - Maya Zhe Wang
- Department of Neuroscience, University of Minnesota, Minneapolis, MN 55455, United States
| | | | - Marc A Sommer
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, United States; Department of Neurobiology, Duke University School of Medicine, Durham, NC 27708, United States; Center for Cognitive Neuroscience, Duke University, Durham, NC 27708, United States
| | - Sarah R Heilbronner
- Department of Neuroscience, University of Minnesota, Minneapolis, MN 55455, United States.
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Villalba RM, Pare JF, Lee S, Lee S, Smith Y. Thalamic degeneration in MPTP-treated Parkinsonian monkeys: impact upon glutamatergic innervation of striatal cholinergic interneurons. Brain Struct Funct 2019; 224:3321-3338. [PMID: 31679085 PMCID: PMC6878768 DOI: 10.1007/s00429-019-01967-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 10/04/2019] [Indexed: 12/13/2022]
Abstract
In both Parkinson's disease (PD) patients and MPTP-treated non-human primates, there is a profound neuronal degeneration of the intralaminar centromedian/parafascicular (CM/Pf) thalamic complex. Although this thalamic pathology has long been established in PD (and other neurodegenerative disorders), the impact of CM/Pf cell loss on the integrity of the thalamo-striatal glutamatergic system and its regulatory functions upon striatal neurons remain unknown. In the striatum, cholinergic interneurons (ChIs) are important constituents of the striatal microcircuitry and represent one of the main targets of CM/Pf-striatal projections. Using light and electron microscopy approaches, we have analyzed the potential impact of CM/Pf neuronal loss on the anatomy of the synaptic connections between thalamic terminals (vGluT2-positive) and ChIs neurons in the striatum of parkinsonian monkeys treated chronically with MPTP. The following conclusions can be drawn from our observations: (1) as reported in PD patients, and in our previous monkey study, CM/Pf neurons undergo profound degeneration in monkeys chronically treated with low doses of MPTP. (2) In the caudate (head and body) nucleus of parkinsonian monkeys, there is an increased density of ChIs. (3) Despite the robust loss of CM/Pf neurons, no significant change was found in the density of thalamostriatal (vGluT2-positive) terminals, and in the prevalence of vGluT2-positive terminals in contact with ChIs in parkinsonian monkeys. These findings provide new information about the state of thalamic innervation of the striatum in parkinsonian monkeys with CM/Pf degeneration, and bring up an additional level of intricacy to the consequences of thalamic pathology upon the functional microcircuitry of the thalamostriatal system in parkinsonism. Future studies are needed to assess the importance of CM/Pf neuronal loss, and its potential consequences on the neuroplastic changes induced in the synaptic organization of the thalamostriatal system, in the development of early cognitive impairments in PD.
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Affiliation(s)
- Rosa M Villalba
- Division of Neuropharmacology and Neurological Diseases, Yerkes National Primate Research Center, Emory University, 954, Gatewood Rd NE, Atlanta, GA, 303, USA.
- UDALL Center for Excellence for Parkinson's Disease, Emory University, Atlanta, GA, USA.
| | - Jean-Francois Pare
- Division of Neuropharmacology and Neurological Diseases, Yerkes National Primate Research Center, Emory University, 954, Gatewood Rd NE, Atlanta, GA, 303, USA
- UDALL Center for Excellence for Parkinson's Disease, Emory University, Atlanta, GA, USA
| | - Solah Lee
- Division of Neuropharmacology and Neurological Diseases, Yerkes National Primate Research Center, Emory University, 954, Gatewood Rd NE, Atlanta, GA, 303, USA
- UDALL Center for Excellence for Parkinson's Disease, Emory University, Atlanta, GA, USA
| | - Sol Lee
- Division of Neuropharmacology and Neurological Diseases, Yerkes National Primate Research Center, Emory University, 954, Gatewood Rd NE, Atlanta, GA, 303, USA
- UDALL Center for Excellence for Parkinson's Disease, Emory University, Atlanta, GA, USA
| | - Yoland Smith
- Division of Neuropharmacology and Neurological Diseases, Yerkes National Primate Research Center, Emory University, 954, Gatewood Rd NE, Atlanta, GA, 303, USA
- Department of Neurology, School of Medicine, Emory University, Atlanta, GA, USA
- UDALL Center for Excellence for Parkinson's Disease, Emory University, Atlanta, GA, USA
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10
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Schwarz MK, Remy S. Rabies virus-mediated connectivity tracing from single neurons. J Neurosci Methods 2019; 325:108365. [DOI: 10.1016/j.jneumeth.2019.108365] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 07/09/2019] [Accepted: 07/14/2019] [Indexed: 02/01/2023]
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Chidambaram SB, Rathipriya AG, Bolla SR, Bhat A, Ray B, Mahalakshmi AM, Manivasagam T, Thenmozhi AJ, Essa MM, Guillemin GJ, Chandra R, Sakharkar MK. Dendritic spines: Revisiting the physiological role. Prog Neuropsychopharmacol Biol Psychiatry 2019; 92:161-193. [PMID: 30654089 DOI: 10.1016/j.pnpbp.2019.01.005] [Citation(s) in RCA: 150] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2018] [Revised: 01/04/2019] [Accepted: 01/12/2019] [Indexed: 12/11/2022]
Abstract
Dendritic spines are small, thin, specialized protrusions from neuronal dendrites, primarily localized in the excitatory synapses. Sophisticated imaging techniques revealed that dendritic spines are complex structures consisting of a dense network of cytoskeletal, transmembrane and scaffolding molecules, and numerous surface receptors. Molecular signaling pathways, mainly Rho and Ras family small GTPases pathways that converge on actin cytoskeleton, regulate the spine morphology and dynamics bi-directionally during synaptic activity. During synaptic plasticity the number and shapes of dendritic spines undergo radical reorganizations. Long-term potentiation (LTP) induction promote spine head enlargement and the formation and stabilization of new spines. Long-term depression (LTD) results in their shrinkage and retraction. Reports indicate increased spine density in the pyramidal neurons of autism and Fragile X syndrome patients and reduced density in the temporal gyrus loci of schizophrenic patients. Post-mortem reports of Alzheimer's brains showed reduced spine number in the hippocampus and cortex. This review highlights the spine morphogenesis process, the activity-dependent structural plasticity and mechanisms by which synaptic activity sculpts the dendritic spines, the structural and functional changes in spines during learning and memory using LTP and LTD processes. It also discusses on spine status in neurodegenerative diseases and the impact of nootropics and neuroprotective agents on the functional restoration of dendritic spines.
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Affiliation(s)
- Saravana Babu Chidambaram
- Department of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research (JSSAHER), Mysuru, Karnataka 570015, India.
| | - A G Rathipriya
- Food and Brain Research Foundation, Chennai, Tamil Nadu, India
| | - Srinivasa Rao Bolla
- Department of Anatomy, College of Medicine, Imam Abdulrahman Bin Faisal University, Damam, Saudi Arabia
| | - Abid Bhat
- Department of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research (JSSAHER), Mysuru, Karnataka 570015, India
| | - Bipul Ray
- Department of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research (JSSAHER), Mysuru, Karnataka 570015, India
| | - Arehally Marappa Mahalakshmi
- Department of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research (JSSAHER), Mysuru, Karnataka 570015, India
| | - Thamilarasan Manivasagam
- Department of Biochemistry and Biotechnology, Faculty of Science, Annamalai University, Annamalainagar, Tamilnadu, India
| | - Arokiasamy Justin Thenmozhi
- Department of Biochemistry and Biotechnology, Faculty of Science, Annamalai University, Annamalainagar, Tamilnadu, India
| | - Musthafa Mohamed Essa
- Department of Food Science and Nutrition, CAMS, Sultan Qaboos University, Muscat, Oman
| | - Gilles J Guillemin
- Neuropharmacology Group, Faculty of Medicine and Health Sciences, Deb Bailey MND Research Laboratory, Macquarie University, Sydney, NSW 2109, Australia
| | - Ramesh Chandra
- Department of Chemistry, Ambedkar Centre for BioMedical Research, Delhi University, Delhi 110007, India
| | - Meena Kishore Sakharkar
- College of Pharmacy and Nutrition, University of Saskatchewan, 107, Wiggins Road, Saskatoon, SK S7N 5C9, Canada.
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13
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Sun L, Tang Y, Yan K, Yu J, Zou Y, Xu W, Xiao K, Zhang Z, Li W, Wu B, Hu Z, Chen K, Fu ZF, Dai J, Cao G. Differences in neurotropism and neurotoxicity among retrograde viral tracers. Mol Neurodegener 2019; 14:8. [PMID: 30736827 PMCID: PMC6368820 DOI: 10.1186/s13024-019-0308-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Accepted: 01/13/2019] [Indexed: 01/01/2023] Open
Abstract
Background Neurotropic virus-based tracers have been extensively applied in mapping and manipulation of neural circuits. However, their neurotropic and neurotoxic properties remain to be fully characterized. Methods Through neural circuit tracing, we systematically compared the neurotropism discrepancy among different multi-trans-synaptic and mono-synaptic retrograde viral tracers including pseudorabies virus (PRV), rabies virus (RV), and the newly engineered retro adeno-associated virus (rAAV2-retro) tracers. The (single-cell) RNA sequencing analysis was utilized for seeking possible attribution to neurotropism discrepancy and comparing cell toxicity caused by viral infection between glycoprotein-deleted RV (RV-∆G) and rAAV2-retro. Viral toxicity induced microglia activation and neuronal protein change were evaluated by immunohistochemistry. Results Multi-trans-synaptic retrograde viral tracers, PRV and RV, exhibit differential neurotropism when they were used for central neural circuit tracing from popliteal lymph nodes. Mono-synaptic retrograde tracers, including RV-∆G and rAAV2-retro, displayed discrepant neurotropic property, when they were applied to trace the inputs of lateral hypothalamic area and medial preoptic nucleus. rAAV2-retro demonstrated preference in cerebral cortex, whereas RV-∆G prefers to label basal ganglia and hypothalamus. Remarkably, we detected a distinct preference for specific cortical layer of rAAV2-retro in layer 5 and RV-∆G in layer 6 when they were injected into dorsal lateral geniculate nucleus to label corticothalamic neurons in primary visual cortex. Complementation of TVA receptor gene in RV-resistant neurons enabled EnvA-pseudotyped RV infection, supporting receptors attribution to viral neurotropism. Furthermore, both RV-∆G and rAAV2-retro exerted neurotoxic influence at the injection sites and retrogradely labeled sites, while the changes were more profound for RV-∆G infection. Finally, we demonstrated a proof-of-concept strategy for more comprehensive high-order circuit tracing of a specific target nucleus by combining rAAV2-retro, RV, and rAAV tracers. Conclusions Different multi-trans-synaptic and mono-synaptic retrograde viral tracers exhibited discrepant neurotropism within certain brain regions, even cortical layer preference. More neurotoxicity was observed under RV-∆G infection as compared with rAAV2-retro. By combining rAAV2-retro, RV, and rAAV tracers, high-order circuit tracing can be achieved. Our findings provide important reference for appropriate application of viral tracers to delineate the landscape and dissect the function of neural network. Electronic supplementary material The online version of this article (10.1186/s13024-019-0308-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Leqiang Sun
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, China.,College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, China
| | - Yajie Tang
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, China.,College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, China
| | - Keji Yan
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, China.,College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, China
| | - Jinsong Yu
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, China.,College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, China
| | - Yanyan Zou
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, China.,College of Informatics, Huazhong Agricultural University, Wuhan, 430070, China
| | - Weize Xu
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, China.,College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, China
| | - Ke Xiao
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, China.,College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, China
| | - Zhihui Zhang
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, China.,College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, China
| | - Weiming Li
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, China.,College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, China
| | - Beili Wu
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, China.,College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, China
| | - Zhe Hu
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Kening Chen
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Zhen F Fu
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, China.,College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, China.,Departments of Pathology, College of Veterinary Medicine, University of Georgia, Athens, GA, 30602, USA
| | - Jinxia Dai
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, China. .,Bio-Medical Center, Huazhong Agricultural University, Wuhan, 430070, China. .,College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, China. .,Key Laboratory of Preventive Veterinary Medicine in Hubei Province, Wuhan, 430070, China.
| | - Gang Cao
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, China. .,Bio-Medical Center, Huazhong Agricultural University, Wuhan, 430070, China. .,College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, China. .,Key Laboratory of Preventive Veterinary Medicine in Hubei Province, Wuhan, 430070, China.
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14
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Abstract
Rhabdoviruses are enveloped viruses with a negative-sense single strand RNA genome and are widespread among a great variety of organisms. In their membrane, they have a single glycoprotein (G) that mediates both virus attachment to cellular receptors and fusion between viral and endosomal membranes allowing viral genome release in the cytoplasm. We present structural and cellular aspects of Rhabdovirus entry into their host cell with a focus on vesicular stomatitis virus (VSV) and rabies virus (RABV) for which the early events of the viral cycle have been extensively studied. Recent data have shown that the only VSV receptors are the members of the LDL-R family. This is in contrast with RABV for which multiple receptors belonging to unrelated families have been identified. Despite having different receptors, after attachment, rhabdovirus internalization occurs through clathrin-mediated endocytosis (CME) in an actin-dependent manner. There are still debates about the exact endocytic pathway of VSV in the cell and on RABV transport in the neuronal axon. In any case, fusion is triggered in the endosomal vesicle via a low-pH induced structural rearrangement of G from its pre- to its postfusion conformation. Vesiculovirus G is one of the best characterized fusion glycoproteins as the previously reported crystal structures of the pre- and postfusion states have been recently completed by those of intermediates during the structural transition. Understanding the entry pathway of rhabdoviruses may have strong impact in biotechnologies as, for example, VSV G is used for pseudotyping lentiviruses to promote efficient transduction, and VSV is a promising oncolytic virus.
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15
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Gasparini SJ, Llonch S, Borsch O, Ader M. Transplantation of photoreceptors into the degenerative retina: Current state and future perspectives. Prog Retin Eye Res 2018; 69:1-37. [PMID: 30445193 DOI: 10.1016/j.preteyeres.2018.11.001] [Citation(s) in RCA: 116] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Revised: 10/29/2018] [Accepted: 11/06/2018] [Indexed: 12/12/2022]
Abstract
The mammalian retina displays no intrinsic regenerative capacities, therefore retinal degenerative diseases such as age-related macular degeneration (AMD) or retinitis pigmentosa (RP) result in a permanent loss of the light-sensing photoreceptor cells. The degeneration of photoreceptors leads to vision impairment and, in later stages, complete blindness. Several therapeutic strategies have been developed to slow down or prevent further retinal degeneration, however a definitive cure i.e. replacement of the lost photoreceptors, has not yet been established. Cell-based treatment approaches, by means of photoreceptor transplantation, have been studied in pre-clinical animal models over the last three decades. The introduction of pluripotent stem cell-derived retinal organoids represents, in principle, an unlimited source for the generation of transplantable human photoreceptors. However, safety, immunological and reproducibility-related issues regarding the use of such cells still need to be solved. Moreover, the recent finding of cytoplasmic material transfer between donor and host photoreceptors demands reinterpretation of several former transplantation studies. At the same time, material transfer between healthy donor and dysfunctional patient photoreceptors also offers a potential alternative strategy for therapeutic intervention. In this review we discuss the history and current state of photoreceptor transplantation, the techniques used to assess rescue of visual function, the prerequisites for effective transplantation as well as the main roadblocks, including safety and immune response to the graft, that need to be overcome for successful clinical translation of photoreceptor transplantation approaches.
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Affiliation(s)
- Sylvia J Gasparini
- CRTD/Center for Regenerative Therapies Dresden, Center for Molecular and Cellular Bioengineering (CMCB), Technische Universität Dresden, Fetscherstraße 105, 01307, Dresden, Germany
| | - Sílvia Llonch
- CRTD/Center for Regenerative Therapies Dresden, Center for Molecular and Cellular Bioengineering (CMCB), Technische Universität Dresden, Fetscherstraße 105, 01307, Dresden, Germany
| | - Oliver Borsch
- CRTD/Center for Regenerative Therapies Dresden, Center for Molecular and Cellular Bioengineering (CMCB), Technische Universität Dresden, Fetscherstraße 105, 01307, Dresden, Germany
| | - Marius Ader
- CRTD/Center for Regenerative Therapies Dresden, Center for Molecular and Cellular Bioengineering (CMCB), Technische Universität Dresden, Fetscherstraße 105, 01307, Dresden, Germany.
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16
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Deussing JM, Chen A. The Corticotropin-Releasing Factor Family: Physiology of the Stress Response. Physiol Rev 2018; 98:2225-2286. [DOI: 10.1152/physrev.00042.2017] [Citation(s) in RCA: 127] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The physiological stress response is responsible for the maintenance of homeostasis in the presence of real or perceived challenges. In this function, the brain activates adaptive responses that involve numerous neural circuits and effector molecules to adapt to the current and future demands. A maladaptive stress response has been linked to the etiology of a variety of disorders, such as anxiety and mood disorders, eating disorders, and the metabolic syndrome. The neuropeptide corticotropin-releasing factor (CRF) and its relatives, the urocortins 1–3, in concert with their receptors (CRFR1, CRFR2), have emerged as central components of the physiological stress response. This central peptidergic system impinges on a broad spectrum of physiological processes that are the basis for successful adaptation and concomitantly integrate autonomic, neuroendocrine, and behavioral stress responses. This review focuses on the physiology of CRF-related peptides and their cognate receptors with the aim of providing a comprehensive up-to-date overview of the field. We describe the major molecular features covering aspects of gene expression and regulation, structural properties, and molecular interactions, as well as mechanisms of signal transduction and their surveillance. In addition, we discuss the large body of published experimental studies focusing on state-of-the-art genetic approaches with high temporal and spatial precision, which collectively aimed to dissect the contribution of CRF-related ligands and receptors to different levels of the stress response. We discuss the controversies in the field and unravel knowledge gaps that might pave the way for future research directions and open up novel opportunities for therapeutic intervention.
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Affiliation(s)
- Jan M. Deussing
- Department of Stress Neurobiology and Neurogenetics, Max Planck Institute of Psychiatry, Munich, Germany; and Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel
| | - Alon Chen
- Department of Stress Neurobiology and Neurogenetics, Max Planck Institute of Psychiatry, Munich, Germany; and Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel
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17
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Commisso B, Ding L, Varadi K, Gorges M, Bayer D, Boeckers TM, Ludolph AC, Kassubek J, Müller OJ, Roselli F. Stage-dependent remodeling of projections to motor cortex in ALS mouse model revealed by a new variant retrograde-AAV9. eLife 2018; 7:36892. [PMID: 30136928 PMCID: PMC6125125 DOI: 10.7554/elife.36892] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Accepted: 08/21/2018] [Indexed: 01/18/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is characterized by the progressive degeneration of motoneurons in the primary motor cortex (pMO) and in spinal cord. However, the pathogenic process involves multiple subnetworks in the brain and functional MRI studies demonstrate an increase in functional connectivity in areas connected to pMO despite the ongoing neurodegeneration. The extent and the structural basis of the motor subnetwork remodeling in experimentally tractable models remain unclear. We have developed a new retrograde AAV9 to quantitatively map the projections to pMO in the SOD1(G93A) ALS mouse model. We show an increase in the number of neurons projecting from somatosensory cortex to pMO at presymptomatic stages, followed by an increase in projections from thalamus, auditory cortex and contralateral MO (inputs from 20 other structures remains unchanged) as disease advances. The stage- and structure-dependent remodeling of projection to pMO in ALS may provide insights into the hyperconnectivity observed in ALS patients.
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Affiliation(s)
| | - Lingjun Ding
- Department of Neurology, University of Ulm, Ulm, Germany
| | - Karl Varadi
- Department of Internal Medicine III, University Hospital Heidelberg, Heidelberg, Germany
| | - Martin Gorges
- Department of Neurology, University of Ulm, Ulm, Germany
| | - David Bayer
- Department of Neurology, University of Ulm, Ulm, Germany
| | - Tobias M Boeckers
- Department of Anatomy and Cell biology, University of Ulm, Ulm, Germany
| | | | - Jan Kassubek
- Department of Neurology, University of Ulm, Ulm, Germany
| | - Oliver J Müller
- Department of Internal Medicine, University of Kiel, Kiel, Germany
| | - Francesco Roselli
- Department of Neurology, University of Ulm, Ulm, Germany.,Department of Anatomy and Cell biology, University of Ulm, Ulm, Germany
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18
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van den Hurk M, Erwin JA, Yeo GW, Gage FH, Bardy C. Patch-Seq Protocol to Analyze the Electrophysiology, Morphology and Transcriptome of Whole Single Neurons Derived From Human Pluripotent Stem Cells. Front Mol Neurosci 2018; 11:261. [PMID: 30147644 PMCID: PMC6096303 DOI: 10.3389/fnmol.2018.00261] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Accepted: 07/12/2018] [Indexed: 11/13/2022] Open
Abstract
The human brain is composed of a complex assembly of about 171 billion heterogeneous cellular units (86 billion neurons and 85 billion non-neuronal glia cells). A comprehensive description of brain cells is necessary to understand the nervous system in health and disease. Recently, advances in genomics have permitted the accurate analysis of the full transcriptome of single cells (scRNA-seq). We have built upon such technical progress to combine scRNA-seq with patch-clamping electrophysiological recording and morphological analysis of single human neurons in vitro. This new powerful method, referred to as Patch-seq, enables a thorough, multimodal profiling of neurons and permits us to expose the links between functional properties, morphology, and gene expression. Here, we present a detailed Patch-seq protocol for isolating single neurons from in vitro neuronal cultures. We have validated the Patch-seq whole-transcriptome profiling method with human neurons generated from embryonic and induced pluripotent stem cells (ESCs/iPSCs) derived from healthy subjects, but the procedure may be applied to any kind of cell type in vitro. Patch-seq may be used on neurons in vitro to profile cell types and states in depth to unravel the human molecular basis of neuronal diversity and investigate the cellular mechanisms underlying brain disorders.
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Affiliation(s)
- Mark van den Hurk
- Laboratory for Human Neurophysiology and Genetics, South Australian Health and Medical Research Institute (SAHMRI) Mind and Brain, Adelaide, SA, Australia
| | - Jennifer A Erwin
- The Lieber Institute for Brain Development, Baltimore, MD, United States.,Department of Neurology, School of Medicine, Johns Hopkins University, Baltimore, MD, United States
| | - Gene W Yeo
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA, United States.,Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Fred H Gage
- Laboratory of Genetics, Salk Institute for Biological Studies, Sanford Consortium for Regenerative Medicine, La Jolla, CA, United States
| | - Cedric Bardy
- Laboratory for Human Neurophysiology and Genetics, South Australian Health and Medical Research Institute (SAHMRI) Mind and Brain, Adelaide, SA, Australia.,Flinders University College of Medicine and Public Health, Adelaide, SA, Australia
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19
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D5 dopamine receptors control glutamatergic AMPA transmission between the motor cortex and subthalamic nucleus. Sci Rep 2018; 8:8858. [PMID: 29891970 PMCID: PMC5995923 DOI: 10.1038/s41598-018-27195-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Accepted: 05/25/2018] [Indexed: 12/23/2022] Open
Abstract
Corticofugal fibers target the subthalamic nucleus (STN), a component nucleus of the basal ganglia, in addition to the striatum, their main input. The cortico-subthalamic, or hyperdirect, pathway, is thought to supplement the cortico-striatal pathways in order to interrupt/change planned actions. To explore the previously unknown properties of the neurons that project to the STN, retrograde and anterograde tools were used to specifically identify them in the motor cortex and selectively stimulate their synapses in the STN. The cortico-subthalamic neurons exhibited very little sag and fired an initial doublet followed by non-adapting action potentials. In the STN, AMPA/kainate synaptic currents had a voltage-dependent conductance, indicative of GluA2-lacking receptors and were partly inhibited by Naspm. AMPA transmission displayed short-term depression, with the exception of a limited bandpass in the 5 to 15 Hz range. AMPA synaptic currents were negatively controlled by dopamine D5 receptors. The reduction in synaptic strength was due to postsynaptic D5 receptors, mediated by a PKA-dependent pathway, but did not involve a modified rectification index. Our data indicated that dopamine, through post-synaptic D5 receptors, limited the cortical drive onto STN neurons in the normal brain.
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20
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Sun S, Schaffer DV. Engineered viral vectors for functional interrogation, deconvolution, and manipulation of neural circuits. Curr Opin Neurobiol 2018; 50:163-170. [PMID: 29614429 PMCID: PMC5984719 DOI: 10.1016/j.conb.2017.12.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Revised: 11/27/2017] [Accepted: 12/16/2017] [Indexed: 12/19/2022]
Abstract
Optimization of traditional replication-competent viral tracers has granted access to immediate synaptic partners of target neuronal populations, enabling the dissection of complex brain circuits into functional neural pathways. The excessive virulence of most conventional tracers, however, impedes their utility in revealing and genetically perturbing cellular function on long time scales. As a promising alternative, the natural capacity of adeno-associated viral (AAV) vectors to safely mediate persistent and robust gene expression has stimulated strong interest in adapting them for sparse neuronal labeling and physiological studies. Furthermore, increasingly refined engineering strategies have yielded novel AAV variants with enhanced target specificity, transduction, and retrograde trafficking in the CNS. These potent vectors offer new opportunities for characterizing the identity and connectivity of single neurons within immense networks and modulating their activity via robust delivery of functional genetic tools.
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Affiliation(s)
- Sabrina Sun
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, CA, USA
| | - David V Schaffer
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, CA, USA; Department of Bioengineering, University of California, Berkeley, CA, USA; The Helen Wills Neuroscience Institute, University of California, Berkeley, CA, USA; Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA.
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21
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Wu Q, Han Y, Tong Q. Current Genetic Techniques in Neural Circuit Control of Feeding and Energy Metabolism. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1090:211-233. [PMID: 30390293 DOI: 10.1007/978-981-13-1286-1_12] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The current epidemic of obesity and its associated metabolic syndromes imposes unprecedented challenges to our society. Despite intensive research focus on obesity pathogenesis, an effective therapeutic strategy to treat and cure obesity is still lacking. The obesity development is due to a disturbed homeostatic control of feeding and energy expenditure, both of which are controlled by an intricate neural network in the brain. Given the inherent complexity of brain networks in controlling feeding and energy expenditure, the understanding of brain-based pathophysiology for obesity development is limited. One key limiting factor in dissecting neural pathways for feeding and energy expenditure is unavailability of techniques that can be used to effectively reduce the complexity of the brain network to a tractable paradigm, based on which a strong hypothesis can be tested. Excitingly, emerging techniques have been involved to be able to link specific groups of neurons and neural pathways to behaviors (i.e., feeding and energy expenditure). In this chapter, novel techniques especially those based on animal models and viral vector approaches will be discussed. We hope that this chapter will provide readers with a basis that can help to understand the literatures using these techniques and with a guide to apply these exciting techniques to investigate brain mechanisms underlying feeding and energy expenditure.
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Affiliation(s)
- Qi Wu
- Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA. .,Children's Nutrition Research Center, Research Service of Department of Agriculture of USA, Houston, TX, USA.
| | - Yong Han
- Department of Pediatrics, Baylor College of Medicine, USDA-ARS, Houston, TX, USA
| | - Qingchun Tong
- Center for Metabolic and Degenerative Diseases, Brown Foundation Institute of Molecular Medicine, University of Texas McGovern Medical School, Houston, TX, USA.
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22
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Dodd GT, Tiganis T. Insulin action in the brain: Roles in energy and glucose homeostasis. J Neuroendocrinol 2017; 29. [PMID: 28758251 DOI: 10.1111/jne.12513] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Revised: 07/05/2017] [Accepted: 07/26/2017] [Indexed: 12/14/2022]
Abstract
A growing body of evidence from research in rodents and humans has identified insulin as an important neuoregulatory peptide in the brain, where it coordinates diverse aspects of energy balance and peripheral glucose homeostasis. This review discusses where and how insulin interacts within the brain and evaluates the physiological and pathophysiological consequences of central insulin signalling in metabolism, obesity and type 2 diabetes.
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Affiliation(s)
- G T Dodd
- Metabolic Disease and Obesity Program, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Melbourne, VIC, Australia
| | - T Tiganis
- Metabolic Disease and Obesity Program, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Melbourne, VIC, Australia
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23
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Chavez C, Zaborszky L. Basal Forebrain Cholinergic-Auditory Cortical Network: Primary Versus Nonprimary Auditory Cortical Areas. Cereb Cortex 2017; 27:2335-2347. [PMID: 27073229 DOI: 10.1093/cercor/bhw091] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Acetylcholine (ACh) release in the cortex is critical for learning, memory, attention, and plasticity. Here, we explore the cholinergic and noncholinergic projections from the basal forebrain (BF) to the auditory cortex using classical retrograde and monosynaptic viral tracers deposited in electrophysiologically identified regions of the auditory cortex. Cholinergic input to both primary (A1) and nonprimary auditory cortical (belt) areas originates in a restricted area in the caudal BF within the globus pallidus (GP) and in the dorsal part of the substantia innominata (SId). On the other hand, we found significant differences in the proportions of cholinergic and noncholinergic projection neurons to primary and nonprimary auditory areas. Inputs to A1 projecting cholinergic neurons were restricted to the GP, caudate-putamen, and the medial part of the medial geniculate body, including the posterior intralaminar thalamic group. In addition to these areas, afferents to belt-projecting cholinergic neurons originated from broader areas, including the ventral secondary auditory cortex, insular cortex, secondary somatosensory cortex, and the central amygdaloid nucleus. These findings support a specific BF projection pattern to auditory cortical areas. Additionally, these findings point to potential functional differences in how ACh release may be regulated in the A1 and auditory belt areas.
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Affiliation(s)
- Candice Chavez
- Center for Molecular and Behavioral Neuroscience, Rutgers State University, Newark, NJ 07102, USA
| | - Laszlo Zaborszky
- Center for Molecular and Behavioral Neuroscience, Rutgers State University, Newark, NJ 07102, USA
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24
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Galvan A, Caiola MJ, Albaugh DL. Advances in optogenetic and chemogenetic methods to study brain circuits in non-human primates. J Neural Transm (Vienna) 2017; 125:547-563. [PMID: 28238201 DOI: 10.1007/s00702-017-1697-8] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Accepted: 02/14/2017] [Indexed: 12/22/2022]
Abstract
Over the last 10 years, the use of opto- and chemogenetics to modulate neuronal activity in research applications has increased exponentially. Both techniques involve the genetic delivery of artificial proteins (opsins or engineered receptors) that are expressed on a selective population of neurons. The firing of these neurons can then be manipulated using light sources (for opsins) or by systemic administration of exogenous compounds (for chemogenetic receptors). Opto- and chemogenetic tools have enabled many important advances in basal ganglia research in rodent models, yet these techniques have faced a slow progress in non-human primate (NHP) research. In this review, we present a summary of the current state of these techniques in NHP research and outline some of the main challenges associated with the use of these genetic-based approaches in monkeys. We also explore cutting-edge developments that will facilitate the use of opto- and chemogenetics in NHPs, and help advance our understanding of basal ganglia circuits in normal and pathological conditions.
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Affiliation(s)
- Adriana Galvan
- Department of Neurology, Yerkes National Primate Research Center, School of Medicine, Emory University, Atlanta, GA, 30329, USA. .,Udall Center of Excellence for Parkinson's Disease Research, Emory University, 954 Gatewood Road NE, Atlanta, GA, 30329, USA. .,Department of Neurology, School of Medicine, Emory University, Atlanta, GA, 30322, USA.
| | - Michael J Caiola
- Department of Neurology, Yerkes National Primate Research Center, School of Medicine, Emory University, Atlanta, GA, 30329, USA.,Udall Center of Excellence for Parkinson's Disease Research, Emory University, 954 Gatewood Road NE, Atlanta, GA, 30329, USA
| | - Daniel L Albaugh
- Department of Neurology, Yerkes National Primate Research Center, School of Medicine, Emory University, Atlanta, GA, 30329, USA.,Udall Center of Excellence for Parkinson's Disease Research, Emory University, 954 Gatewood Road NE, Atlanta, GA, 30329, USA
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25
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Gielow MR, Zaborszky L. The Input-Output Relationship of the Cholinergic Basal Forebrain. Cell Rep 2017; 18:1817-1830. [PMID: 28199851 PMCID: PMC5725195 DOI: 10.1016/j.celrep.2017.01.060] [Citation(s) in RCA: 133] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2016] [Revised: 12/05/2016] [Accepted: 01/24/2017] [Indexed: 12/21/2022] Open
Abstract
Basal forebrain cholinergic neurons influence cortical state, plasticity, learning, and attention. They collectively innervate the entire cerebral cortex, differentially controlling acetylcholine efflux across different cortical areas and timescales. Such control might be achieved by differential inputs driving separable cholinergic outputs, although no input-output relationship on a brain-wide level has ever been demonstrated. Here, we identify input neurons to cholinergic cells projecting to specific cortical regions by infecting cholinergic axon terminals with a monosynaptically restricted viral tracer. This approach revealed several circuit motifs, such as central amygdala neurons synapsing onto basolateral amygdala-projecting cholinergic neurons or strong somatosensory cortical input to motor cortex-projecting cholinergic neurons. The presence of input cells in the parasympathetic midbrain nuclei contacting frontally projecting cholinergic neurons suggest that the network regulating the inner eye muscles are additionally regulating cortical state via acetylcholine efflux. This dataset enables future circuit-level experiments to identify drivers of known cortical cholinergic functions.
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Affiliation(s)
- Matthew R Gielow
- Center for Molecular and Behavioral Neuroscience, Rutgers, the State University of New Jersey, Newark, NJ 07102, USA
| | - Laszlo Zaborszky
- Center for Molecular and Behavioral Neuroscience, Rutgers, the State University of New Jersey, Newark, NJ 07102, USA.
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26
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Alsteens D, Newton R, Schubert R, Martinez-Martin D, Delguste M, Roska B, Müller DJ. Nanomechanical mapping of first binding steps of a virus to animal cells. NATURE NANOTECHNOLOGY 2017; 12:177-183. [PMID: 27798607 DOI: 10.1038/nnano.2016.228] [Citation(s) in RCA: 124] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Accepted: 09/18/2016] [Indexed: 05/23/2023]
Abstract
Viral infection is initiated when a virus binds to cell surface receptors. Because the cell membrane is dynamic and heterogeneous, imaging living cells and simultaneously quantifying the first viral binding events is difficult. Here, we show an atomic force and confocal microscopy set-up that allows the surface receptor landscape of cells to be imaged and the virus binding events within the first millisecond of contact with the cell to be mapped at high resolution (<50 nm). We present theoretical approaches to contour the free-energy landscape of early binding events between an engineered virus and cell surface receptors. We find that the first bond formed between the viral glycoprotein and its cognate cell surface receptor has relatively low lifetime and free energy, but this increases as additional bonds form rapidly (≤1 ms). The formation of additional bonds occurs with positive allosteric modulation and the three binding sites of the viral glycoprotein are quickly occupied. Our quantitative approach can be readily applied to study the binding of other viruses to animal cells.
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Affiliation(s)
- David Alsteens
- ETH Zürich, Department of Biosystems Science and Engineering, 4058 Basel, Switzerland
- Université Catholique de Louvain, Institute of Life Sciences, 1348 Louvain-La-Neuve, Belgium
| | - Richard Newton
- ETH Zürich, Department of Biosystems Science and Engineering, 4058 Basel, Switzerland
| | - Rajib Schubert
- ETH Zürich, Department of Biosystems Science and Engineering, 4058 Basel, Switzerland
| | - David Martinez-Martin
- ETH Zürich, Department of Biosystems Science and Engineering, 4058 Basel, Switzerland
| | - Martin Delguste
- Université Catholique de Louvain, Institute of Life Sciences, 1348 Louvain-La-Neuve, Belgium
| | - Botond Roska
- Friedrich Miescher Institute (FMI), 4058 Basel, Switzerland
- Department of Ophthalmology, University of Basel, 4056 Basel, Switzerland
| | - Daniel J Müller
- ETH Zürich, Department of Biosystems Science and Engineering, 4058 Basel, Switzerland
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27
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Bohmbach K, Schwarz MK, Schoch S, Henneberger C. The structural and functional evidence for vesicular release from astrocytes in situ. Brain Res Bull 2017; 136:65-75. [PMID: 28122264 DOI: 10.1016/j.brainresbull.2017.01.015] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Revised: 01/17/2017] [Accepted: 01/19/2017] [Indexed: 12/31/2022]
Abstract
The concept of the tripartite synapse states that bi-directional signalling between perisynaptic astrocyte processes, presynaptic axonal boutons and postsynaptic neuronal structures defines the properties of synaptic information processing. Ca2+-dependent vesicular release from astrocytes, as one of the mechanisms of astrocyte-neuron communication, has attracted particular attention but has also been the subject of intense debate. In neurons, regulated vesicular release is a strongly coordinated process. It requires a complex release machinery comprised of many individual components ranging from vesicular neurotransmitter transporters and soluble NSF attachment protein receptors (SNARE) proteins to Ca2+-sensors and the proteins that spatially and temporally control exocytosis of synaptic vesicles. If astrocytes employ similar mechanisms to release neurotransmitters is less well understood. The aim of this review is therefore to discuss recent experimental evidence that sheds light on the central structural components responsible for vesicular release from astrocytes in situ.
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Affiliation(s)
- Kirsten Bohmbach
- Institute of Cellular Neurosciences, University of Bonn Medical School, Bonn, Germany.
| | - Martin K Schwarz
- Department of Epileptology, University of Bonn Medical School, Bonn, Germany
| | - Susanne Schoch
- Institute of Neuropathology, University of Bonn Medical School, Bonn, Germany
| | - Christian Henneberger
- Institute of Cellular Neurosciences, University of Bonn Medical School, Bonn, Germany; German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany; Institute of Neurology, University College London, London, United Kingdom.
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28
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Cazemier JL, Clascá F, Tiesinga PHE. Connectomic Analysis of Brain Networks: Novel Techniques and Future Directions. Front Neuroanat 2016; 10:110. [PMID: 27881953 PMCID: PMC5101213 DOI: 10.3389/fnana.2016.00110] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Accepted: 10/25/2016] [Indexed: 12/31/2022] Open
Abstract
Brain networks, localized or brain-wide, exist only at the cellular level, i.e., between specific pre- and post-synaptic neurons, which are connected through functionally diverse synapses located at specific points of their cell membranes. "Connectomics" is the emerging subfield of neuroanatomy explicitly aimed at elucidating the wiring of brain networks with cellular resolution and a quantified accuracy. Such data are indispensable for realistic modeling of brain circuitry and function. A connectomic analysis, therefore, needs to identify and measure the soma, dendrites, axonal path, and branching patterns together with the synapses and gap junctions of the neurons involved in any given brain circuit or network. However, because of the submicron caliber, 3D complexity, and high packing density of most such structures, as well as the fact that axons frequently extend over long distances to make synapses in remote brain regions, creating connectomic maps is technically challenging and requires multi-scale approaches, Such approaches involve the combination of the most sensitive cell labeling and analysis methods available, as well as the development of new ones able to resolve individual cells and synapses with increasing high-throughput. In this review, we provide an overview of recently introduced high-resolution methods, which researchers wanting to enter the field of connectomics may consider. It includes several molecular labeling tools, some of which specifically label synapses, and covers a number of novel imaging tools such as brain clearing protocols and microscopy approaches. Apart from describing the tools, we also provide an assessment of their qualities. The criteria we use assess the qualities that tools need in order to contribute to deciphering the key levels of circuit organization. We conclude with a brief future outlook for neuroanatomic research, computational methods, and network modeling, where we also point out several outstanding issues like structure-function relations and the complexity of neural models.
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Affiliation(s)
- J Leonie Cazemier
- Department of Neuroinformatics, Donders Institute, Radboud UniversityNijmegen, Netherlands; Department of Cortical Structure and Function, Netherlands Institute for NeuroscienceAmsterdam, Netherlands
| | - Francisco Clascá
- Department of Anatomy, Histology and Neuroscience, School of Medicine, Autónoma University Madrid, Spain
| | - Paul H E Tiesinga
- Department of Neuroinformatics, Donders Institute, Radboud University Nijmegen, Netherlands
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29
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Ghanem A, Conzelmann KK. G gene-deficient single-round rabies viruses for neuronal circuit analysis. Virus Res 2016; 216:41-54. [DOI: 10.1016/j.virusres.2015.05.023] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Revised: 05/28/2015] [Accepted: 05/31/2015] [Indexed: 12/11/2022]
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Webber ES, Bonci A, Krashes MJ. The elegance of energy balance: Insight from circuit-level manipulations. Synapse 2016; 69:461-74. [PMID: 26126768 DOI: 10.1002/syn.21837] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Revised: 06/08/2015] [Accepted: 06/16/2015] [Indexed: 01/24/2023]
Abstract
Mechanisms of energy balance were first examined using very powerful neuroscience techniques such as lesions and electrical stimulation. This early work identified the hypothalamus as a key structure involved in hunger and feeding; however, neural resolution of cell-defined populations contributing to appetite regulation remained elusive. Recent innovations in neuroscience have produced constructs that allow for a high degree of specificity in loss- and gain-of-function manipulations in molecularly circumscribed neural subsets as well as monosynaptic circuit mapping and in vivo neurophysiology. These complimentary techniques have provided researchers an unprecedented amount of empirical agility. As a result, cell populations in two subregions of the hypothalamus have emerged as key players in the physiological control of feeding behavior. The arcuate nucleus of the hypothalamus and the paraventricular nucleus of the hypothalamus contain neural populations that have a direct role in the promotion of hunger and satiety. These include neurons that express agouti-related peptide, pro-opiomelanocortin, single-minded homolog 1 protein, and the melanocortin-4 receptor. This review focuses on how these neural subsets communicate with one another, link up to build elaborate networks, and ultimately contribute to alterations in food intake. The continuing advancement of neuroscience tools, as well as a multimodal integration of findings, will be critical in illuminating an exhaustive and clinically relevant hunger circuit.
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Affiliation(s)
- Emily S Webber
- Digestive and Kidney Diseases, Diabetes, Endocrinology and Obesity Branch, National Institute of Diabetes, National Institutes of Health, Bethesda, Maryland
| | - Antonello Bonci
- National Institute of Drug Abuse, National Institutes of Health, Baltimore, Maryland
| | - Michael J Krashes
- Digestive and Kidney Diseases, Diabetes, Endocrinology and Obesity Branch, National Institute of Diabetes, National Institutes of Health, Bethesda, Maryland.,National Institute of Drug Abuse, National Institutes of Health, Baltimore, Maryland
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31
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Sato S, Ohara S, Tsutsui KI, Iijima T. Effects of G-gene Deletion and Replacement on Rabies Virus Vector Gene Expression. PLoS One 2015; 10:e0128020. [PMID: 26023771 PMCID: PMC4449044 DOI: 10.1371/journal.pone.0128020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2014] [Accepted: 04/21/2015] [Indexed: 12/26/2022] Open
Abstract
The glycoprotein-gene (G gene) -deleted rabies virus (RV) vector is a powerful tool to examine the function and structure of neural circuits. We previously reported that the deletion of the G gene enhances the transgene expression level of the RV vector. However, the mechanism of this enhancement remains to be clarified. We presume that there are two possible factors for this enhancement. The first factor is the glycoprotein of RV, which shows cytotoxicity; thus, may cause a dysfunction in the translation process of infected cells. The second possible factor is the enhanced expression of the L gene, which encodes viral RNA polymerase. In the RV, it is known that the gene expression level is altered depending on the position of the gene. Since G-gene deletion displaces the L gene in the genome, the expression of the L gene and viral transcription may be enhanced. In this study, we compared the transgene expression level and viral transcription of three recombinant RV vectors. The effect of glycoprotein was examined by comparing the viral gene expression of G-gene-intact RV and G-gene-replaced RV. Despite the fact that the L-gene transcription level of these two RV vectors was similar, the G-gene-replaced RV vector showed higher viral transcription and transgene expression level than the G-gene-intact RV vector. To examine the effect of the position of the L gene, we compared the viral gene expression of the G-gene-deleted RV and G-gene-replaced RV. The G-gene-deleted RV vector showed higher L-gene transcription, viral transcription, and transgene expression level than the G-gene-replaced RV vector. These results indicate that G-gene deletion enhances the transgene expression level through at least two factors, the absence of glycoprotein and enhancement of L-gene expression. These findings enable investigators to design a useful viral vector that shows a controlled desirable transgene expression level in applications.
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Affiliation(s)
- Sho Sato
- Division of Systems Neuroscience, Tohoku University Graduate School of Life Sciences, Sendai, Japan
| | - Shinya Ohara
- Division of Systems Neuroscience, Tohoku University Graduate School of Life Sciences, Sendai, Japan
| | - Ken-Ichiro Tsutsui
- Division of Systems Neuroscience, Tohoku University Graduate School of Life Sciences, Sendai, Japan
| | - Toshio Iijima
- Division of Systems Neuroscience, Tohoku University Graduate School of Life Sciences, Sendai, Japan
- * E-mail:
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32
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Yamawaki N, Shepherd GMG. Synaptic circuit organization of motor corticothalamic neurons. J Neurosci 2015; 35:2293-307. [PMID: 25653383 PMCID: PMC4315846 DOI: 10.1523/jneurosci.4023-14.2015] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2014] [Revised: 11/24/2014] [Accepted: 12/27/2014] [Indexed: 01/07/2023] Open
Abstract
Corticothalamic (CT) neurons in layer 6 constitute a large but enigmatic class of cortical projection neurons. How they are integrated into intracortical and thalamo-cortico-thalamic circuits is incompletely understood, especially outside of sensory cortex. Here, we investigated CT circuits in mouse forelimb motor cortex (M1) using multiple circuit-analysis methods. Stimulating and recording from CT, intratelencephalic (IT), and pyramidal tract (PT) projection neurons, we found strong CT↔ CT and CT↔ IT connections; however, CT→IT connections were limited to IT neurons in layer 6, not 5B. There was strikingly little CT↔ PT excitatory connectivity. Disynaptic inhibition systematically accompanied excitation in these pathways, scaling with the amplitude of excitation according to both presynaptic (class-specific) and postsynaptic (cell-by-cell) factors. In particular, CT neurons evoked proportionally more inhibition relative to excitation (I/E ratio) than IT neurons. Furthermore, the amplitude of inhibition was tuned to match the amount of excitation at the level of individual neurons; in the extreme, neurons receiving no excitation received no inhibition either. Extending these studies to dissect the connectivity between cortex and thalamus, we found that M1-CT neurons and thalamocortical neurons in the ventrolateral (VL) nucleus were remarkably unconnected in either direction. Instead, VL axons in the cortex excited both IT and PT neurons, and CT axons in the thalamus excited other thalamic neurons, including those in the posterior nucleus, which additionally received PT excitation. These findings, which contrast in several ways with previous observations in sensory areas, illuminate the basic circuit organization of CT neurons within M1 and between M1 and thalamus.
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Affiliation(s)
- Naoki Yamawaki
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611
| | - Gordon M G Shepherd
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611
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Abstract
Rabies is one of the most deadly infectious diseases, with a case-fatality rate approaching 100%. The disease is established on all continents apart from Antarctica; most cases are reported in Africa and Asia, with thousands of deaths recorded annually. However, the estimated annual figure of almost 60,000 human rabies fatalities is probably an underestimate. Almost all cases of human rabies result from bites from infected dogs. Therefore, the most cost-effective approach to elimination of the global burden of human rabies is to control canine rabies rather than expansion of the availability of human prophylaxis. Mass vaccination campaigns with parenteral vaccines, and advances in oral vaccines for wildlife, have allowed the elimination of rabies in terrestrial carnivores in several countries worldwide. The subsequent reduction in cases of human rabies in such regions advocates the multidisciplinary One Health approach to rabies control through the mass vaccination of dogs and control of canine populations.
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Affiliation(s)
- Anthony R Fooks
- Animal Health and Veterinary Laboratories Agency (AHVLA, Weybridge), New Haw, Addlestone, UK; WHO Communicable Disease Surveillance and Response Collaborating Centre for the Characterisation of Rabies and Rabies-related Viruses, Addlestone, Weybridge, UK; Department of Clinical Infection, Microbiology and Immunology, Institute of Infection and Global Health, University of Liverpool, Liverpool, UK; National Consortium for Zoonosis Research, University of Liverpool, Leahurst, Neston, UK.
| | - Ashley C Banyard
- Animal Health and Veterinary Laboratories Agency (AHVLA, Weybridge), New Haw, Addlestone, UK; WHO Communicable Disease Surveillance and Response Collaborating Centre for the Characterisation of Rabies and Rabies-related Viruses, Addlestone, Weybridge, UK
| | - Daniel L Horton
- Animal Health and Veterinary Laboratories Agency (AHVLA, Weybridge), New Haw, Addlestone, UK; WHO Communicable Disease Surveillance and Response Collaborating Centre for the Characterisation of Rabies and Rabies-related Viruses, Addlestone, Weybridge, UK
| | - Nicholas Johnson
- Animal Health and Veterinary Laboratories Agency (AHVLA, Weybridge), New Haw, Addlestone, UK; WHO Communicable Disease Surveillance and Response Collaborating Centre for the Characterisation of Rabies and Rabies-related Viruses, Addlestone, Weybridge, UK
| | - Lorraine M McElhinney
- Animal Health and Veterinary Laboratories Agency (AHVLA, Weybridge), New Haw, Addlestone, UK; WHO Communicable Disease Surveillance and Response Collaborating Centre for the Characterisation of Rabies and Rabies-related Viruses, Addlestone, Weybridge, UK; National Consortium for Zoonosis Research, University of Liverpool, Leahurst, Neston, UK
| | - Alan C Jackson
- Departments of Internal Medicine (Neurology) and of Medical Microbiology, University of Manitoba, Winnipeg, Manitoba, Canada
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Suter BA, Yamawaki N, Borges K, Li X, Kiritani T, Hooks BM, Shepherd GMG. Neurophotonics applications to motor cortex research. NEUROPHOTONICS 2014; 1:011008. [PMID: 25553337 PMCID: PMC4278379 DOI: 10.1117/1.nph.1.1.011008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Revised: 04/16/2014] [Accepted: 04/18/2014] [Indexed: 06/04/2023]
Abstract
Neurophotonics methods offer powerful ways to access neuronal signals and circuits. We highlight recent advances and current themes in this area, emphasizing tools for mapping, monitoring, and manipulating excitatory projection neurons and their synaptic circuits in mouse motor cortex.
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Affiliation(s)
- Benjamin A. Suter
- Northwestern University, Feinberg School of Medicine, Department of Physiology, Chicago, Illinois 60611
| | - Naoki Yamawaki
- Northwestern University, Feinberg School of Medicine, Department of Physiology, Chicago, Illinois 60611
| | - Katharine Borges
- Northwestern University, Feinberg School of Medicine, Department of Physiology, Chicago, Illinois 60611
| | - Xiaojian Li
- Northwestern University, Feinberg School of Medicine, Department of Physiology, Chicago, Illinois 60611
| | - Taro Kiritani
- Northwestern University, Feinberg School of Medicine, Department of Physiology, Chicago, Illinois 60611
| | - Bryan M. Hooks
- Howard Hughes Medical Institute, Janelia Farm Research Campus, Ashburn, Virginia 20147
| | - Gordon M. G. Shepherd
- Northwestern University, Feinberg School of Medicine, Department of Physiology, Chicago, Illinois 60611
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35
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An anterograde rabies virus vector for high-resolution large-scale reconstruction of 3D neuron morphology. Brain Struct Funct 2014; 220:1369-79. [PMID: 24723034 PMCID: PMC4409643 DOI: 10.1007/s00429-014-0730-z] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2013] [Accepted: 02/07/2014] [Indexed: 12/19/2022]
Abstract
Glycoprotein-deleted rabies virus (RABV ∆G) is a powerful tool for the analysis of neural circuits. Here, we demonstrate the utility of an anterograde RABV ∆G variant for novel neuroanatomical approaches involving either bulk or sparse neuronal populations. This technology exploits the unique features of RABV ∆G vectors, namely autonomous, rapid high-level expression of transgenes, and limited cytotoxicity. Our vector permits the unambiguous long-range and fine-scale tracing of the entire axonal arbor of individual neurons throughout the brain. Notably, this level of labeling can be achieved following infection with a single viral particle. The vector is effective over a range of ages (>14 months) aiding the studies of neurodegenerative disorders or aging, and infects numerous cell types in all brain regions tested. Lastly, it can also be readily combined with retrograde RABV ∆G variants. Together with other modern technologies, this tool provides new possibilities for the investigation of the anatomy and physiology of neural circuits.
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36
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Vivar C, van Praag H. Functional circuits of new neurons in the dentate gyrus. Front Neural Circuits 2013; 7:15. [PMID: 23443839 PMCID: PMC3580993 DOI: 10.3389/fncir.2013.00015] [Citation(s) in RCA: 101] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2012] [Accepted: 01/23/2013] [Indexed: 01/17/2023] Open
Abstract
The hippocampus is crucial for memory formation. New neurons are added throughout life to the hippocampal dentate gyrus (DG), a brain area considered important for differential storage of similar experiences and contexts. To better understand the functional contribution of adult neurogenesis to pattern separation processes, we recently used a novel synapse specific trans-neuronal tracing approach to identify the (sub) cortical inputs to new dentate granule cells (GCs). It was observed that newly born neurons receive sequential innervation from structures important for memory function. Initially, septal-hippocampal cells provide input to new neurons, including transient innervation from mature GCs as well as direct feedback from area CA3 pyramidal neurons. After about 1 month perirhinal (PRH) and lateral entorhinal cortex (LEC), brain areas deemed relevant to integration of novel sensory and environmental information, become substantial input to new GCs. Here, we review the developmental time-course and proposed functional relevance of new neurons, within the context of their unique neural circuitry.
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Affiliation(s)
- Carmen Vivar
- Neuroplasticity and Behavior Unit, Laboratory of Neurosciences, Intramural Research Program, National Institute on Aging, National Institutes of Health Baltimore, MD, USA
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37
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Nagai Y. Reverse Genetics of Mononegavirales: The Rabies Virus Paradigm. SENDAI VIRUS VECTOR 2013. [PMCID: PMC7121350 DOI: 10.1007/978-4-431-54556-9_1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The neurotropic rabies virus (RABV) is a prototype member of the Mononegavirales order of viruses and is the most significant human pathogen of the Rhabdoviridae family. A reverse genetics system for RABV was established almost 20 years ago, providing a paradigm for other Mononegavirales members as well. The availability of engineered recombinant viruses opened a new era to study common aspects of Mononegavirales biology and specific aspects of the unique lifestyle and pathogenesis of individual members. Above all, the knowledge gained has allowed engineering of beneficial biomedical tools such as viral vectors, vaccines, and tracers. In this chapter, the development of the classical rabies virus reverse genetics approach is described, and some of the most exciting biomedical applications for recombinant RABV and other Mononegavirales are briefly addressed.
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