51
|
Hira R, Ohkubo F, Masamizu Y, Ohkura M, Nakai J, Okada T, Matsuzaki M. Reward-timing-dependent bidirectional modulation of cortical microcircuits during optical single-neuron operant conditioning. Nat Commun 2014; 5:5551. [PMID: 25418042 DOI: 10.1038/ncomms6551] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Accepted: 10/13/2014] [Indexed: 01/27/2023] Open
Abstract
Animals rapidly adapt to environmental change. To reveal how cortical microcircuits are rapidly reorganized when an animal recognizes novel reward contingency, we conduct two-photon calcium imaging of layer 2/3 motor cortex neurons in mice and simultaneously reinforce the activity of a single cortical neuron with water delivery. Here we show that when the target neuron is not relevant to a pre-trained forelimb movement, the mouse increases the target neuron activity and the number of rewards delivered during 15-min operant conditioning without changing forelimb movement behaviour. The reinforcement bidirectionally modulates the activity of subsets of non-target neurons, independent of distance from the target neuron. The bidirectional modulation depends on the relative timing between the reward delivery and the neuronal activity, and is recreated by pairing reward delivery and photoactivation of a subset of neurons. Reward-timing-dependent bidirectional modulation may be one of the fundamental processes in microcircuit reorganization for rapid adaptation.
Collapse
Affiliation(s)
- Riichiro Hira
- 1] Division of Brain Circuits, National Institute for Basic Biology and the Graduate University of Advanced Studies (Sokendai), Myodaiji, Okazaki, Japan [2] Japan Science and Technology Agency, CREST, Saitama 332-0012, Japan
| | - Fuki Ohkubo
- 1] Division of Brain Circuits, National Institute for Basic Biology and the Graduate University of Advanced Studies (Sokendai), Myodaiji, Okazaki, Japan [2] Japan Science and Technology Agency, CREST, Saitama 332-0012, Japan
| | - Yoshito Masamizu
- 1] Division of Brain Circuits, National Institute for Basic Biology and the Graduate University of Advanced Studies (Sokendai), Myodaiji, Okazaki, Japan [2] Japan Science and Technology Agency, CREST, Saitama 332-0012, Japan
| | - Masamichi Ohkura
- Brain Science Institute, Saitama University, Saitama 338-8570, Japan
| | - Junichi Nakai
- Brain Science Institute, Saitama University, Saitama 338-8570, Japan
| | - Takashi Okada
- Department of Biochemistry and Molecular Biology, Nippon Medical School, Tokyo 113-8602, Japan
| | - Masanori Matsuzaki
- 1] Division of Brain Circuits, National Institute for Basic Biology and the Graduate University of Advanced Studies (Sokendai), Myodaiji, Okazaki, Japan [2] Japan Science and Technology Agency, CREST, Saitama 332-0012, Japan
| |
Collapse
|
52
|
Murlidharan G, Samulski RJ, Asokan A. Biology of adeno-associated viral vectors in the central nervous system. Front Mol Neurosci 2014; 7:76. [PMID: 25285067 PMCID: PMC4168676 DOI: 10.3389/fnmol.2014.00076] [Citation(s) in RCA: 129] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Accepted: 09/04/2014] [Indexed: 01/11/2023] Open
Abstract
Gene therapy is a promising approach for treating a spectrum of neurological and neurodegenerative disorders by delivering corrective genes to the central nervous system (CNS). In particular, adeno-associated viruses (AAVs) have emerged as promising tools for clinical gene transfer in a broad range of genetic disorders with neurological manifestations. In the current review, we have attempted to bridge our understanding of the biology of different AAV strains with their transduction profiles, cellular tropisms, and transport mechanisms within the CNS. Continued efforts to dissect AAV-host interactions within the brain are likely to aid in the development of improved vectors for CNS-directed gene transfer applications in the clinic.
Collapse
Affiliation(s)
- Giridhar Murlidharan
- Curriculum in Genetics and Molecular Biology, School of Medicine, University of North Carolina at Chapel Hill Chapel Hill, NC, USA ; Gene Therapy Center, School of Medicine, University of North Carolina at Chapel Hill Chapel Hill, NC, USA
| | - Richard J Samulski
- Gene Therapy Center, School of Medicine, University of North Carolina at Chapel Hill Chapel Hill, NC, USA ; Department of Pharmacology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill NC, USA
| | - Aravind Asokan
- Gene Therapy Center, School of Medicine, University of North Carolina at Chapel Hill Chapel Hill, NC, USA ; Department of Genetics and Department of Biochemistry and Biophysics, School of Medicine, University of North Carolina at Chapel Hill Chapel Hill, NC, USA
| |
Collapse
|
53
|
Comparative analyses of adeno-associated viral vector serotypes 1, 2, 5, 8 and 9 in marmoset, mouse and macaque cerebral cortex. Neurosci Res 2014; 93:144-57. [PMID: 25240284 DOI: 10.1016/j.neures.2014.09.002] [Citation(s) in RCA: 220] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Revised: 08/26/2014] [Accepted: 08/27/2014] [Indexed: 01/06/2023]
Abstract
Here we investigated the transduction characteristics of adeno-associated viral vector (AAV) serotypes 1, 2, 5, 8 and 9 in the marmoset cerebral cortex. Using three constructs that each has hrGFP under ubiquitous (CMV), or neuron-specific (CaMKII and Synapsin I (SynI)) promoters, we investigated (1) the extent of viral spread, (2) cell type tropism, and (3) neuronal transduction efficiency of each serotype. AAV2 was clearly distinct from other serotypes in small spreading and neuronal tropism. We did not observe significant differences in viral spread among other serotypes. Regarding the cell tropism, AAV1, 5, 8 and 9 exhibited mostly glial expression for CMV construct. However, when the CaMKII construct was tested, cortical neurons were efficiently transduced (>∼70% in layer 3) by all serotypes, suggesting that glial expression obscured neuronal expression for CMV construct. For both SynI and CaMKII constructs, we observed generally high-level expression in large pyramidal cells especially in layer 5, as well as in parvalbumin-positive interneurons. The expression from the CaMKII construct was more uniformly observed in excitatory cells compared with SynI construct. Injection of the same viral preparations in mouse and macaque cortex resulted in essentially the same result with some species-specific differences.
Collapse
|
54
|
Masamizu Y, Tanaka YR, Tanaka YH, Hira R, Ohkubo F, Kitamura K, Isomura Y, Okada T, Matsuzaki M. Two distinct layer-specific dynamics of cortical ensembles during learning of a motor task. Nat Neurosci 2014; 17:987-94. [PMID: 24880217 DOI: 10.1038/nn.3739] [Citation(s) in RCA: 127] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Accepted: 05/07/2014] [Indexed: 12/14/2022]
Abstract
The primary motor cortex (M1) possesses two intermediate layers upstream of the motor-output layer: layer 2/3 (L2/3) and layer 5a (L5a). Although repetitive training often improves motor performance and movement coding by M1 neuronal ensembles, it is unclear how neuronal activities in L2/3 and L5a are reorganized during motor task learning. We conducted two-photon calcium imaging in mouse M1 during 14 training sessions of a self-initiated lever-pull task. In L2/3, the accuracy of neuronal ensemble prediction of lever trajectory remained unchanged globally, with a subset of individual neurons retaining high prediction accuracy throughout the training period. However, in L5a, the ensemble prediction accuracy steadily improved, and one-third of neurons, including subcortical projection neurons, evolved to contribute substantially to ensemble prediction in the late stage of learning. The L2/3 network may represent coordination of signals from other areas throughout learning, whereas L5a may participate in the evolving network representing well-learned movements.
Collapse
Affiliation(s)
- Yoshito Masamizu
- 1] Division of Brain Circuits, National Institute for Basic Biology, Okazaki, Aichi, Japan. [2] CREST, Japan Science and Technology Agency, Saitama, Japan. [3]
| | - Yasuhiro R Tanaka
- 1] Division of Brain Circuits, National Institute for Basic Biology, Okazaki, Aichi, Japan. [2] CREST, Japan Science and Technology Agency, Saitama, Japan. [3]
| | - Yasuyo H Tanaka
- 1] Division of Brain Circuits, National Institute for Basic Biology, Okazaki, Aichi, Japan. [2] CREST, Japan Science and Technology Agency, Saitama, Japan
| | - Riichiro Hira
- 1] Division of Brain Circuits, National Institute for Basic Biology, Okazaki, Aichi, Japan. [2] CREST, Japan Science and Technology Agency, Saitama, Japan
| | - Fuki Ohkubo
- 1] Division of Brain Circuits, National Institute for Basic Biology, Okazaki, Aichi, Japan. [2] CREST, Japan Science and Technology Agency, Saitama, Japan. [3] The Graduate University of Advanced Studies (Sokendai), Okazaki, Aichi, Japan
| | - Kazuo Kitamura
- 1] CREST, Japan Science and Technology Agency, Saitama, Japan. [2] Department of Neurophysiology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan. [3] PREST, Japan Science and Technology Agency, Saitama, Japan
| | - Yoshikazu Isomura
- 1] CREST, Japan Science and Technology Agency, Saitama, Japan. [2] Brain Science Institute, Tamagawa University, Tokyo, Japan
| | - Takashi Okada
- 1] Department of Biochemistry and Molecular Biology, Nippon Medical School, Tokyo, Japan. [2] Department of Molecular Therapy, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Masanori Matsuzaki
- 1] Division of Brain Circuits, National Institute for Basic Biology, Okazaki, Aichi, Japan. [2] CREST, Japan Science and Technology Agency, Saitama, Japan. [3] The Graduate University of Advanced Studies (Sokendai), Okazaki, Aichi, Japan
| |
Collapse
|
55
|
Castle MJ, Gershenson ZT, Giles AR, Holzbaur ELF, Wolfe JH. Adeno-associated virus serotypes 1, 8, and 9 share conserved mechanisms for anterograde and retrograde axonal transport. Hum Gene Ther 2014; 25:705-20. [PMID: 24694006 DOI: 10.1089/hum.2013.189] [Citation(s) in RCA: 109] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Adeno-associated virus (AAV) vectors often undergo long-distance axonal transport after brain injection. This leads to transduction of brain regions distal to the injection site, although the extent of axonal transport and distal transduction varies widely among AAV serotypes. The mechanisms driving this variability are poorly understood. This is a critical problem for applications that require focal gene expression within a specific brain region, and also impedes the utilization of vector transport for applications requiring widespread delivery of transgene to the brain. Here, we compared AAV serotypes 1 and 9, which frequently demonstrate distal transduction, with serotype 8, which rarely spreads beyond the injection site. To examine directional AAV transport in vitro, we used a microfluidic chamber to apply dye-labeled AAV to the axon termini or to the cell bodies of primary rat embryonic cortical neurons. All three serotypes were actively transported along axons, with transport characterized by high velocities and prolonged runs in both the anterograde and retrograde directions. Coinfection with pairs of serotypes indicated that AAV1, 8, and 9 share the same intracellular compartments for axonal transport. In vivo, both AAV8 and 9 demonstrated anterograde and retrograde transport within a nonreciprocal circuit after injection into adult mouse brain, with highly similar distributions of distal transduction. However, in mass-cultured neurons, we found that AAV1 was more frequently transported than AAV8 or 9, and that the frequency of AAV9 transport could be enhanced by increasing receptor availability. Thus, while these serotypes share conserved mechanisms for axonal transport both in vitro and in vivo, the frequency of transport can vary among serotypes, and axonal transport can be markedly increased by enhancing vector uptake. This suggests that variability in distal transduction in vivo likely results from differential uptake at the plasma membrane, rather than fundamental differences in transport mechanisms among AAV serotypes.
Collapse
Affiliation(s)
- Michael J Castle
- 1 Research Institute of the Children's Hospital of Philadelphia , Philadelphia, PA 19104
| | | | | | | | | |
Collapse
|
56
|
Wickersham IR, Sullivan HA, Seung HS. Axonal and subcellular labelling using modified rabies viral vectors. Nat Commun 2014; 4:2332. [PMID: 23945836 PMCID: PMC5939574 DOI: 10.1038/ncomms3332] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Accepted: 07/19/2013] [Indexed: 01/03/2023] Open
Abstract
An important aspect of any neural circuit is the placement of its output synapses, at levels ranging from macroscopic to subcellular. The many new molecular tools for locating and manipulating synapses are limited by the viral vectors available for delivering them. Adeno-associated viruses are the best current means of labeling and manipulating axons and synapses, but they have never expressed more than one transgene highly enough to label fine axonal structure while also labeling or perturbing synapses. Their slow expression also makes them incompatible with retrograde and transsynaptic vectors, preventing powerful combinatorial experiments. Here we show that deletion-mutant rabies virus can be specifically targeted to cells local to an injection site, brightly labeling axons even when coexpressing two other transgenes. We demonstrate several novel capabilities: simultaneously labeling axons and presynaptic terminals, labeling both dendrites and postsynaptic densities, and simultaneously labeling a region’s inputs and outputs using coinjected vectors.
Collapse
Affiliation(s)
- Ian R Wickersham
- Department of Brain & Cognitive Sciences, Massachusetts Institute of Technology, 43 Vassar Street, Cambridge, Massachusetts 02139, USA
| | | | | |
Collapse
|
57
|
Transgene expression in target-defined neuron populations mediated by retrograde infection with adeno-associated viral vectors. J Neurosci 2013; 33:15195-206. [PMID: 24048849 DOI: 10.1523/jneurosci.1618-13.2013] [Citation(s) in RCA: 88] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Tools enabling the manipulation of well defined neuronal subpopulations are critical for probing complex neuronal networks. Cre recombinase (Cre) mouse driver lines in combination with the Cre-dependent expression of proteins using viral vectors--in particular, recombinant adeno-associated viral vectors (rAAVs)--have emerged as a widely used platform for achieving transgene expression in specified neural populations. However, the ability of rAAVs to further specify neuronal subsets on the basis of their anatomical connectivity has been reported as limited or inconsistent. Here, we systematically tested a variety of widely used neurotropic rAAVs for their ability to mediate retrograde gene transduction in the mouse brain. We tested pseudotyped rAAVs of several common serotypes (rAAV 2/1, 2/5, and 2/9) as well as constructs both with and without Cre-dependent expression switches. Many of the rAAVs tested--in particular, though not exclusively, Cre-dependent vectors--showed a robust capacity for retrograde infection and transgene expression. Retrograde expression was successful over distances as large as 6 mm and in multiple neuron types, including olfactory projection neurons, neocortical pyramidal cells projecting to distinct targets, and corticofugal and modulatory projection neurons. Retrograde infection using transgenes such as ChR2 allowed for optical control or optically assisted electrophysiological identification of neurons defined genetically as well as by their projection target. These results establish a widely accessible tool for achieving combinatorial specificity and stable, long-term transgene expression to isolate precisely defined neuron populations in the intact animal.
Collapse
|
58
|
Adeno-associated virus serotypes 9 and rh10 mediate strong neuronal transduction of the dog brain. Gene Ther 2013; 21:28-36. [PMID: 24131981 PMCID: PMC3881028 DOI: 10.1038/gt.2013.54] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Revised: 08/23/2013] [Accepted: 08/28/2013] [Indexed: 12/20/2022]
Abstract
Canine models have many advantages for evaluating therapy of human central nervous system (CNS) diseases. In contrast to nonhuman primate models, naturally occurring canine CNS diseases are common. In contrast to murine models, the dog's lifespan is long, its brain is large and the diseases affecting it commonly have the same molecular, pathological and clinical phenotype as the human diseases. We compared the ability of four intracerebrally injected adeno-associated virus vector (AAV) serotypes to transduce the dog brain with green fluorescent protein as the first step in using these vectors to evaluate both delivery and efficacy in naturally occurring canine homologs of human diseases. Quantitative measures of transduction, maximum diameter and area, identified both AAV2/9 and AAV2/rh10 as significantly more efficient than either AAV2/1 or AAV2/5 at transducing cerebral cortex, caudate nucleus, thalamus and internal capsule. Fluorescence co-labeling with cell-type-specific antibodies demonstrated that AAV2/9 and AAV2/rh10 were capable of primarily transducing neurons, although glial transduction was also identified and found to be more efficient with the AAV2/9 vector. These data are a prerequisite to evaluating the efficacy of recombinant AAV vectors carrying disease-modifying transgenes to treat naturally occurring canine models in preclinical studies of human CNS disease therapy.
Collapse
|
59
|
Analysis of transduction efficiency, tropism and axonal transport of AAV serotypes 1, 2, 5, 6, 8 and 9 in the mouse brain. PLoS One 2013; 8:e76310. [PMID: 24086725 PMCID: PMC3785459 DOI: 10.1371/journal.pone.0076310] [Citation(s) in RCA: 405] [Impact Index Per Article: 33.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2013] [Accepted: 08/23/2013] [Indexed: 12/31/2022] Open
Abstract
Recombinant Adeno-associated virus vectors (rAAV) are widely used for gene delivery and multiple naturally occurring serotypes have been harnessed to target cells in different tissues and organs including the brain. Here, we provide a detailed and quantitative analysis of the transduction profiles of rAAV vectors based on six of the most commonly used serotypes (AAV1, AAV2, AAV5, AAV6, AAV8, AAV9) that allows systematic comparison and selection of the optimal vector for a specific application. In our studies we observed marked differences among serotypes in the efficiency to transduce three different brain regions namely the striatum, hippocampus and neocortex of the mouse. Despite the fact that the analyzed serotypes have the general ability to transduce all major cell types in the brain (neurons, microglia, astrocytes and oligodendrocytes), the expression level of a reporter gene driven from a ubiquitous promoter varies significantly for specific cell type / serotype combinations. For example, rAAV8 is particularly efficient to drive transgene expression in astrocytes while rAAV9 appears well suited for the transduction of cortical neurons. Interestingly, we demonstrate selective retrograde transport of rAAV5 along axons projecting from the ventral part of the entorhinal cortex to the dentate gyrus. Furthermore, we show that self-complementing rAAV can be used to significantly decrease the time required for the onset of transgene expression in the mouse brain.
Collapse
|
60
|
Chen SJ, Johnston J, Sandhu A, Bish LT, Hovhannisyan R, Jno-Charles O, Sweeney HL, Wilson JM. Enhancing the utility of adeno-associated virus gene transfer through inducible tissue-specific expression. Hum Gene Ther Methods 2013; 24:270-8. [PMID: 23895325 PMCID: PMC3753727 DOI: 10.1089/hgtb.2012.129] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2012] [Accepted: 06/04/2013] [Indexed: 01/12/2023] Open
Abstract
The ability to regulate both the timing and specificity of gene expression mediated by viral vectors will be important in maximizing its utility. We describe the development of an adeno-associated virus (AAV)-based vector with tissue-specific gene regulation, using the ARGENT dimerizer-inducible system. This two-vector system based on AAV serotype 9 consists of one vector encoding a combination of reporter genes from which expression is directed by a ubiquitous, inducible promoter and a second vector encoding transcription factor domains under the control of either a heart- or liver-specific promoter, which are activated with a small molecule. Administration of the vectors via either systemic or intrapericardial injection demonstrated that the vector system is capable of mediating gene expression that is tissue specific, regulatable, and reproducible over induction cycles. Somatic gene transfer in vivo is being considered in therapeutic applications, although its most substantial value will be in basic applications such as target validation and development of animal models.
Collapse
Affiliation(s)
- Shu-Jen Chen
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Julie Johnston
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Arbans Sandhu
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Lawrence T. Bish
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Ruben Hovhannisyan
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Odella Jno-Charles
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - H. Lee Sweeney
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - James M. Wilson
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104
| |
Collapse
|
61
|
Intraspinal AAV Injections Immediately Rostral to a Thoracic Spinal Cord Injury Site Efficiently Transduces Neurons in Spinal Cord and Brain. MOLECULAR THERAPY-NUCLEIC ACIDS 2013; 2:e108. [PMID: 23881451 PMCID: PMC3731889 DOI: 10.1038/mtna.2013.34] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Accepted: 05/03/2013] [Indexed: 12/18/2022]
Abstract
In the vast majority of studies utilizing adeno-associated virus (AAV) in central nervous system applications, including those published with spinal cord injury (SCI) models, AAV has been administered at the level of the cell body of neurons targeted for genetic modification, resulting in transduction of neurons in the vicinity of the injection site. However, as SCI interrupts many axon tracts, it may be more beneficial to transduce a diverse pool of supraspinal neurons. We determined if descending axons severed by SCI are capable of retrogradely transporting AAV to remotely transduce a variety of brain regions. Different AAV serotypes encoding the reporter green fluorescent protein (GFP) were injected into gray and white matter immediately rostral to a spinal transection site. This resulted in the transduction of thousands of neurons within the spinal cord and in multiple regions within the brainstem that project to spinal cord. In addition, we established that different serotypes had disparate regional specificity and that AAV5 transduced the most brain and spinal cord neurons. This is the first demonstration that retrograde transport of AAV by axons severed by SCI is an effective means to transduce a collection of supraspinal neurons. Thus, we identify a novel, minimally invasive means to transduce a variety of neuronal populations within both the spinal cord and the brain following SCI. This paradigm to broadly distribute viral vectors has the potential to be an important component of a combinatorial strategy to promote functional axonal regeneration.
Collapse
|
62
|
Robust Long-term Transduction of Common Marmoset Neuromuscular Tissue With rAAV1 and rAAV9. MOLECULAR THERAPY-NUCLEIC ACIDS 2013; 2:e95. [PMID: 23715217 PMCID: PMC4817936 DOI: 10.1038/mtna.2013.21] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Profiles of recombinant adeno-associated virus (rAAV)-mediated transduction show interspecies differences for each AAV serotype. Robust long-term transgene expression is generally observed in rodents, whereas insufficient transduction is seen in animals with more advanced immune systems. Non-human primates, including the common marmoset, could provide appropriate models for neuromuscular diseases because of their higher brain functions and physiological resemblance to humans. Strategies to induce pathologies in the neuromuscular tissues of non-human primates by rAAV-mediated transduction are promising; however, transgene expression patterns with rAAV transduction have not been elucidated in marmosets. In this study, transduction of adult marmoset skeletal muscle with rAAV9 led to robust and persistent enhanced green fluorescent protein (EGFP) expression that was independent of the muscle fiber type, although lymphocyte infiltration was recognized. Systemic rAAV injection into pregnant marmosets led to transplacental fetal transduction. Surprisingly, the intraperitoneal injection of rAAV1 and rAAV9 into the neonatal marmoset resulted in systemic transduction and persistent transgene expression without lymphocyte infiltration. Skeletal and cardiac muscle were effectively transduced with rAAV1 and rAAV9, respectively. Interestingly, rAAV9 transduction led to intense EGFP signaling in the axons of the corpus callosum. These transduction protocols with rAAV will be useful for investigating gene functions in the neuromuscular tissues and developing gene therapy strategies.
Collapse
|
63
|
Yawo H, Asano T, Sakai S, Ishizuka T. Optogenetic manipulation of neural and non-neural functions. Dev Growth Differ 2013; 55:474-90. [PMID: 23550617 DOI: 10.1111/dgd.12053] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2012] [Revised: 02/25/2013] [Accepted: 02/26/2013] [Indexed: 01/22/2023]
Abstract
Optogenetic manipulation of the neuronal activity enables one to analyze the neuronal network both in vivo and in vitro with precise spatio-temporal resolution. Channelrhodopsins (ChRs) are light-sensitive cation channels that depolarize the cell membrane, whereas halorhodopsins and archaerhodopsins are light-sensitive Cl(-) and H(+) transporters, respectively, that hyperpolarize it when exogenously expressed. The cause-effect relationship between a neuron and its function in the brain is thus bi-directionally investigated with evidence of necessity and sufficiency. In this review we discuss the potential of optogenetics with a focus on three major requirements for its application: (i) selection of the light-sensitive proteins optimal for optogenetic investigation, (ii) targeted expression of these selected proteins in a specific group of neurons, and (iii) targeted irradiation with high spatiotemporal resolution. We also discuss recent progress in the application of optogenetics to studies of non-neural cells such as glial cells, cardiac and skeletal myocytes. In combination with stem cell technology, optogenetics may be key to successful research using embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) derived from human patients through optical regulation of differentiation-maturation, through optical manipulation of tissue transplants and, furthermore, through facilitating survival and integration of transplants.
Collapse
Affiliation(s)
- Hiromu Yawo
- Department of Developmental Biology and Neuroscience, Tohoku University Graduate School of Life Sciences, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan.
| | | | | | | |
Collapse
|
64
|
Hira R, Ohkubo F, Tanaka YR, Masamizu Y, Augustine GJ, Kasai H, Matsuzaki M. In vivo optogenetic tracing of functional corticocortical connections between motor forelimb areas. Front Neural Circuits 2013; 7:55. [PMID: 23554588 PMCID: PMC3612597 DOI: 10.3389/fncir.2013.00055] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2012] [Accepted: 03/11/2013] [Indexed: 12/26/2022] Open
Abstract
Interactions between distinct motor cortical areas are essential for coordinated motor behaviors. In rodents, the motor cortical forelimb areas are divided into at least two distinct areas: the rostral forelimb area (RFA) and the caudal forelimb area (CFA). The RFA is thought to be an equivalent of the premotor cortex (PM) in primates, whereas the CFA is believed to be an equivalent of the primary motor cortex. Although reciprocal connections between the RFA and the CFA have been anatomically identified in rats, it is unknown whether there are functional connections between these areas that can induce postsynaptic spikes. In this study, we used an in vivo Channelrhodopsin-2 (ChR2) photostimulation method to trace the functional connections between the mouse RFA and CFA. Simultaneous electrical recordings were utilized to detect spiking activities induced by synaptic inputs originating from photostimulated areas. This method, in combination with anatomical tracing, demonstrated that the RFA receives strong functional projections from layer 2/3 and/or layer 5a, but not from layer 5b (L5b), of the CFA. Further, the CFA receives strong projections from L5b neurons of the RFA. The onset latency of electrical responses evoked in remote areas upon photostimulation of the other areas was approximately 10 ms, which is consistent with the synaptic connectivity between these areas. Our results suggest that neuronal activities in the RFA and the CFA during movements are formed through asymmetric reciprocal connections.
Collapse
Affiliation(s)
- Riichiro Hira
- Division of Brain Circuits, National Institute for Basic Biology Okazaki, Japan ; CREST, Japan Science and Technology Agency Saitama, Japan ; Laboratory of Structural Physiology, Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, University of Tokyo Tokyo, Japan
| | | | | | | | | | | | | |
Collapse
|
65
|
|
66
|
An optogenetic approach in epilepsy. Neuropharmacology 2012; 69:89-95. [PMID: 22698957 DOI: 10.1016/j.neuropharm.2012.05.049] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2012] [Revised: 05/28/2012] [Accepted: 05/29/2012] [Indexed: 12/14/2022]
Abstract
Optogenetic tools comprise a variety of different light-sensitive proteins from single-cell organisms that can be expressed in mammalian neurons and effectively control their excitability. Two main classes of optogenetic tools allow to either depolarize or hyperpolarize, and respectively generate or inhibit action potentials in selective populations of neurons. This opens unprecedented possibilities for delineating the role of certain neuronal populations in brain processing and diseases. Moreover, optogenetics may be considered for developing potential treatment strategies for brain diseases, particularly for excitability disorders such as epilepsy. Expression of the inhibitory halorhodopsin NpHR in hippocampal principal cells has been recently used as a tool to effectively control chemically and electrically induced epileptiform activity in slice preparations, and to reduce in vivo spiking induced by tetanus toxin injection in the motor cortex. In this review we give a comprehensive summary of what has been achieved so far in the field of epilepsy using optogenetics, and discuss some of the possible strategies that could be envisaged in the future. We also point out some of the challenges and pitfalls in relation to possible outcomes of using optogenetics for controlling network excitability, and associated brain diseases. This article is part of the Special Issue entitled 'New Targets and Approaches to the Treatment of Epilepsy'.
Collapse
|
67
|
Dugué GP, Akemann W, Knöpfel T. A comprehensive concept of optogenetics. PROGRESS IN BRAIN RESEARCH 2012; 196:1-28. [PMID: 22341318 DOI: 10.1016/b978-0-444-59426-6.00001-x] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Fundamental questions that neuroscientists have previously approached with classical biochemical and electrophysiological techniques can now be addressed using optogenetics. The term optogenetics reflects the key program of this emerging field, namely, combining optical and genetic techniques. With the already impressively successful application of light-driven actuator proteins such as microbial opsins to interact with intact neural circuits, optogenetics rose to a key technology over the past few years. While spearheaded by tools to control membrane voltage, the more general concept of optogenetics includes the use of a variety of genetically encoded probes for physiological parameters ranging from membrane voltage and calcium concentration to metabolism. Here, we provide a comprehensive overview of the state of the art in this rapidly growing discipline and attempt to sketch some of its future prospects and challenges.
Collapse
Affiliation(s)
- Guillaume P Dugué
- Champalimaud Neuroscience Programme, Instituto Gulbenkian de Ciência, Oeiras, Portugal.
| | | | | |
Collapse
|