1
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Lecca S, Congiu M, Royon L, Restivo L, Girard B, Mazaré N, Bellone C, Telley L, Mameli M. A neural substrate for negative affect dictates female parental behavior. Neuron 2023; 111:1094-1103.e8. [PMID: 36731469 DOI: 10.1016/j.neuron.2023.01.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 11/23/2022] [Accepted: 01/05/2023] [Indexed: 02/04/2023]
Abstract
Parental behaviors secure the well-being of newborns and concomitantly limit negative affective states in adults, which emerge when coping with neonatal distress becomes challenging. Whether negative-affect-related neuronal circuits orchestrate parental actions is unknown. Here, we identify parental signatures in lateral habenula neurons receiving bed nucleus of stria terminalis innervation (BNSTLHb). We find that LHb neurons of virgin female mice increase their activity following pup distress vocalization and are necessary for pup-call-driven aversive behaviors. LHb activity rises during pup retrieval, a behavior worsened by LHb inactivation. Intersectional cell identification and transcriptional profiling associate BNSTLHb cells to parenting and outline a gene expression in female virgins similar to that in mothers but different from that in non-parental virgin male mice. Finally, tracking and manipulating BNSTLHb cell activity demonstrates their specificity for encoding negative affect and pup retrieval. Thus, a negative affect neural circuit processes newborn distress signals and may limit them by guiding female parenting.
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Affiliation(s)
- Salvatore Lecca
- The Department of Fundamental Neuroscience, The University of Lausanne, 1005 Lausanne, Switzerland
| | - Mauro Congiu
- The Department of Fundamental Neuroscience, The University of Lausanne, 1005 Lausanne, Switzerland
| | - Léa Royon
- The Department of Fundamental Neuroscience, The University of Lausanne, 1005 Lausanne, Switzerland
| | - Leonardo Restivo
- The Department of Fundamental Neuroscience, The University of Lausanne, 1005 Lausanne, Switzerland
| | - Benoit Girard
- The Department of Basic Neuroscience, The University of Geneva, 1205 Geneva, Switzerland
| | - Noemie Mazaré
- The Department of Fundamental Neuroscience, The University of Lausanne, 1005 Lausanne, Switzerland
| | - Camilla Bellone
- The Department of Basic Neuroscience, The University of Geneva, 1205 Geneva, Switzerland
| | - Ludovic Telley
- The Department of Fundamental Neuroscience, The University of Lausanne, 1005 Lausanne, Switzerland
| | - Manuel Mameli
- The Department of Fundamental Neuroscience, The University of Lausanne, 1005 Lausanne, Switzerland; Inserm, UMR-S 839, 75005 Paris, France.
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2
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Wei JA, Han Q, Luo Z, Liu L, Cui J, Tan J, Chow BKC, So KF, Zhang L. Amygdala neural ensemble mediates mouse social investigation behaviors. Natl Sci Rev 2022; 10:nwac179. [PMID: 36845323 PMCID: PMC9952061 DOI: 10.1093/nsr/nwac179] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 05/22/2022] [Accepted: 08/15/2022] [Indexed: 11/15/2022] Open
Abstract
Innate social investigation behaviors are critical for animal survival and are regulated by both neural circuits and neuroendocrine factors. Our understanding of how neuropeptides regulate social interest, however, is incomplete at the current stage. In this study, we identified the expression of secretin (SCT) in a subpopulation of excitatory neurons in the basolateral amygdala. With distinct molecular and physiological features, BLASCT+ cells projected to the medial prefrontal cortex and were necessary and sufficient for promoting social investigation behaviors, whilst other basolateral amygdala neurons were anxiogenic and antagonized social behaviors. Moreover, the exogenous application of secretin effectively promoted social interest in both healthy and autism spectrum disorder model mice. These results collectively demonstrate a previously unrecognized group of amygdala neurons for mediating social behaviors and suggest promising strategies for social deficits.
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Affiliation(s)
| | | | | | - Linglin Liu
- Key Laboratory of CNS Regeneration (Ministry of Education), Guangdong-Hong Kong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou 510632, China
| | - Jing Cui
- Key Laboratory of CNS Regeneration (Ministry of Education), Guangdong-Hong Kong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou 510632, China
| | - Jiahui Tan
- Key Laboratory of CNS Regeneration (Ministry of Education), Guangdong-Hong Kong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou 510632, China
| | - Billy K C Chow
- School of Biological Sciences, The University of Hong Kong, Hong Kong, China
| | - Kwok-Fai So
- Key Laboratory of CNS Regeneration (Ministry of Education), Guangdong-Hong Kong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou 510632, China,State Key Laboratory of Brain and Cognitive Science, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China,Center for Brain Science and Brain-Inspired Intelligence, Guangdong-Hong Kong-Macao Greater Bay Area, Guangzhou 510030, China,BiolandLaboratory (Guangzhou Regenerative Medicine and Health Guangdong Laboratory), Guangzhou 510006, China,Co-Innovation Center of Neuroregeneration, Nantong University, Nantong 220619, China,Neuroscience and Neurorehabilitation Institute, University of Health and Rehabilitation Sciences, Qingdao 266113, China,Institute of Clinical Research for Mental Health, Jinan University, Guangzhou 510632, China
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3
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Kostin A, Alam MA, Saevskiy A, McGinty D, Alam MN. Activation of the Ventrolateral Preoptic Neurons Projecting to the Perifornical-Hypothalamic Area Promotes Sleep: DREADD Activation in Wild-Type Rats. Cells 2022; 11:2140. [PMID: 35883583 PMCID: PMC9319714 DOI: 10.3390/cells11142140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 06/18/2022] [Accepted: 06/21/2022] [Indexed: 02/04/2023] Open
Abstract
The ventrolateral preoptic area (VLPO) predominantly contains sleep-active neurons and is involved in sleep regulation. The perifornical-hypothalamic area (PF-HA) is a wake-regulatory region and predominantly contains wake-active neurons. VLPO GABAergic/galaninergic neurons project to the PF-HA. Previously, the specific contribution of VLPO neurons projecting to the PF-HA (VLPO > PF-HAPRJ) in sleep regulation in rats could not be investigated due to the lack of tools that could selectively target these neurons. We determined the contribution of VLPO > PF-HAPRJ neurons in sleep regulation by selectively activating them using designer receptors exclusively activated by designer drugs (DREADDs) in wild-type Fischer-344 rats. We used a combination of two viral vectors to retrogradely deliver the Cre-recombinase gene, specifically, in VLPO > PF-HA neurons, and further express hM3Dq in those neurons to selectively activate them for delineating their specific contributions to sleep−wake functions. Compared to the control, in DREADD rats, clozapine-N-oxide (CNO) significantly increased fos-expression, a marker of neuronal activation, in VLPO > PF-HAPRJ neurons (2% vs. 20%, p < 0.01) during the dark phase. CNO treatment also increased nonREM sleep (27% vs. 40%, p < 0.01) during the first 3 h of the dark phase, when rats are typically awake, and after exposure to the novel environment (55% vs. 65%; p < 0.01), which induces acute arousal during the light phase. These results support a hypothesis that VLPO > PF-HAPRJ neurons constitute a critical component of the hypothalamic sleep−wake regulatory circuitry and promote sleep by suppressing wake-active PF-HA neurons.
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Affiliation(s)
- Andrey Kostin
- Research Service (151A3), Veterans Affairs Greater Los Angeles Healthcare System, 16111 Plummer Street, Sepulveda, Los Angeles, CA 91343, USA; (A.K.); (M.A.A.); (D.M.)
| | - Md. Aftab Alam
- Research Service (151A3), Veterans Affairs Greater Los Angeles Healthcare System, 16111 Plummer Street, Sepulveda, Los Angeles, CA 91343, USA; (A.K.); (M.A.A.); (D.M.)
- Department of Psychiatry, University of California, Los Angeles, CA 90095, USA
| | - Anton Saevskiy
- Scientific Research and Technology Center for Neurotechnology, Southern Federal University, 344006 Rostov-on-Don, Russia;
| | - Dennis McGinty
- Research Service (151A3), Veterans Affairs Greater Los Angeles Healthcare System, 16111 Plummer Street, Sepulveda, Los Angeles, CA 91343, USA; (A.K.); (M.A.A.); (D.M.)
- Department of Psychology, University of California, Los Angeles, CA 90095, USA
| | - Md. Noor Alam
- Research Service (151A3), Veterans Affairs Greater Los Angeles Healthcare System, 16111 Plummer Street, Sepulveda, Los Angeles, CA 91343, USA; (A.K.); (M.A.A.); (D.M.)
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA
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4
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Tadokoro T, Bravo-Hernandez M, Agashkov K, Kobayashi Y, Platoshyn O, Navarro M, Marsala S, Miyanohara A, Yoshizumi T, Shigyo M, Krotov V, Juhas S, Juhasova J, Nguyen D, Kupcova Skalnikova H, Motlik J, Studenovska H, Proks V, Reddy R, Driscoll SP, Glenn TD, Kemthong T, Malaivijitnond S, Tomori Z, Vanicky I, Kakinohana M, Pfaff SL, Ciacci J, Belan P, Marsala M. Precision spinal gene delivery-induced functional switch in nociceptive neurons reverses neuropathic pain. Mol Ther 2022; 30:2722-2745. [PMID: 35524407 PMCID: PMC9372322 DOI: 10.1016/j.ymthe.2022.04.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 03/31/2022] [Accepted: 04/29/2022] [Indexed: 11/17/2022] Open
Abstract
Second-order spinal cord excitatory neurons play a key role in spinal processing and transmission of pain signals to the brain. Exogenously-induced change in developmentally-imprinted excitatory neurotransmitter phenotype of these neurons to inhibitory has not yet been achieved. Here we use a subpial dorsal horn-targeted delivery of AAV (adeno-associated virus) vector(s) encoding GABA (gamma-Aminobutyric acid,) synthesizing-releasing inhibitory machinery in mice with neuropathic pain. Treated animals showed a progressive and complete reversal of neuropathic pain (tactile and brush-evoked pain behavior) which persisted for minimum 2.5 months post-treatment. The mechanism of this treatment effect results from the switch of excitatory to preferential inhibitory neurotransmitter phenotype in dorsal horn nociceptive neurons and a resulting increase in inhibitory activity in regional spinal circuitry after peripheral nociceptive stimulation. No detectable side effects (such as sedation, motor weakness or loss of normal sensation) were seen between 2-13 months post-treatment in naive adult mice, pigs and non-human primates. The use of this treatment approach may represent a potent and safe treatment modality in patients suffering from spinal cord- or peripheral nerve-injury induced neuropathic pain.
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Affiliation(s)
- Takahiro Tadokoro
- Neuroregeneration Laboratory, Department of Anesthesiology, University of California, San Diego (UCSD), La Jolla, CA 92037, USA; Department of Anesthesiology, University of Ryukyus, Okinawa, Japan; Neurgain Technologies, 9620 Towne Centre Drive, Suite 100, San Diego, CA 92121, USA
| | - Mariana Bravo-Hernandez
- Neuroregeneration Laboratory, Department of Anesthesiology, University of California, San Diego (UCSD), La Jolla, CA 92037, USA
| | - Kirill Agashkov
- Departments of Sensory Signaling and Molecular Biophysics, Bogomoletz Institute of Physiology, Kyiv, Ukraine
| | - Yoshiomi Kobayashi
- Neuroregeneration Laboratory, Department of Anesthesiology, University of California, San Diego (UCSD), La Jolla, CA 92037, USA
| | - Oleksandr Platoshyn
- Neuroregeneration Laboratory, Department of Anesthesiology, University of California, San Diego (UCSD), La Jolla, CA 92037, USA
| | - Michael Navarro
- Neuroregeneration Laboratory, Department of Anesthesiology, University of California, San Diego (UCSD), La Jolla, CA 92037, USA
| | - Silvia Marsala
- Neuroregeneration Laboratory, Department of Anesthesiology, University of California, San Diego (UCSD), La Jolla, CA 92037, USA; Neurgain Technologies, 9620 Towne Centre Drive, Suite 100, San Diego, CA 92121, USA
| | - Atsushi Miyanohara
- Neuroregeneration Laboratory, Department of Anesthesiology, University of California, San Diego (UCSD), La Jolla, CA 92037, USA; Vector Core Laboratory, University of California, San Diego (UCSD), La Jolla, CA 92037, USA
| | - Tetsuya Yoshizumi
- Neuroregeneration Laboratory, Department of Anesthesiology, University of California, San Diego (UCSD), La Jolla, CA 92037, USA
| | - Michiko Shigyo
- Neuroregeneration Laboratory, Department of Anesthesiology, University of California, San Diego (UCSD), La Jolla, CA 92037, USA
| | - Volodymyr Krotov
- Departments of Sensory Signaling and Molecular Biophysics, Bogomoletz Institute of Physiology, Kyiv, Ukraine
| | - Stefan Juhas
- Institute of Animal Physiology and Genetics, Czech Academy of Sciences, Rumburská 89, 277 21 Liběchov, Czech Republic
| | - Jana Juhasova
- Institute of Animal Physiology and Genetics, Czech Academy of Sciences, Rumburská 89, 277 21 Liběchov, Czech Republic
| | - Duong Nguyen
- Institute of Animal Physiology and Genetics, Czech Academy of Sciences, Rumburská 89, 277 21 Liběchov, Czech Republic
| | - Helena Kupcova Skalnikova
- Institute of Animal Physiology and Genetics, Czech Academy of Sciences, Rumburská 89, 277 21 Liběchov, Czech Republic
| | - Jan Motlik
- Institute of Animal Physiology and Genetics, Czech Academy of Sciences, Rumburská 89, 277 21 Liběchov, Czech Republic
| | - Hana Studenovska
- Institute of Macromolecular Chemistry, Czech Academy of Sciences, Department of Biomaterials and Bioanalogous Systems, Heyrovsky Square 2,162 06 Prague 6, Czech Republic
| | - Vladimir Proks
- Institute of Macromolecular Chemistry, Czech Academy of Sciences, Department of Biomaterials and Bioanalogous Systems, Heyrovsky Square 2,162 06 Prague 6, Czech Republic
| | - Rajiv Reddy
- Department of Anesthesiology, Pain Medicine, University of California, San Diego (UCSD), La Jolla, CA 92037, USA
| | - Shawn P Driscoll
- Gene Expression Laboratory and the Howard Hughes Medical Institute, Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | - Thomas D Glenn
- Gene Expression Laboratory and the Howard Hughes Medical Institute, Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | - Taratorn Kemthong
- National Primate Research Center of Thailand, Chulalongkorn University, Kaengkhoi District, Saraburi 18110, Thailand
| | - Suchinda Malaivijitnond
- National Primate Research Center of Thailand, Chulalongkorn University, Kaengkhoi District, Saraburi 18110, Thailand
| | - Zoltan Tomori
- Department of Biophysics, Institute of Experimental Physics, Slovak Academy of Sciences, Kosice, Slovakia
| | - Ivo Vanicky
- Institute of Neurobiology, Biomedical Research Center, Slovak Academy of Sciences, Kosice, Slovakia
| | | | - Samuel L Pfaff
- Gene Expression Laboratory and the Howard Hughes Medical Institute, Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | - Joseph Ciacci
- Department of Neurosurgery, University of California, San Diego (UCSD), La Jolla, CA 92037, USA
| | - Pavel Belan
- Departments of Sensory Signaling and Molecular Biophysics, Bogomoletz Institute of Physiology, Kyiv, Ukraine; Kyiv Academic University, Kyiv, Ukraine
| | - Martin Marsala
- Neuroregeneration Laboratory, Department of Anesthesiology, University of California, San Diego (UCSD), La Jolla, CA 92037, USA; Institute of Neurobiology, Biomedical Research Center, Slovak Academy of Sciences, Kosice, Slovakia.
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5
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Sánchez-Bellot C, AlSubaie R, Mishchanchuk K, Wee RWS, MacAskill AF. Two opposing hippocampus to prefrontal cortex pathways for the control of approach and avoidance behaviour. Nat Commun 2022; 13:339. [PMID: 35039510 PMCID: PMC8763938 DOI: 10.1038/s41467-022-27977-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Accepted: 12/13/2021] [Indexed: 11/09/2022] Open
Abstract
The decision to either approach or avoid a potentially threatening environment is thought to rely upon the coordinated activity of heterogeneous neural populations in the hippocampus and prefrontal cortex (PFC). However, how this circuitry is organized to flexibly promote both approach or avoidance at different times has remained elusive. Here, we show that the hippocampal projection to PFC is composed of two parallel circuits located in the superficial or deep pyramidal layers of the CA1/subiculum border. These circuits have unique upstream and downstream connectivity, and are differentially active during approach and avoidance behaviour. The superficial population is preferentially connected to widespread PFC inhibitory interneurons, and its activation promotes exploration; while the deep circuit is connected to PFC pyramidal neurons and fast spiking interneurons, and its activation promotes avoidance. Together this provides a mechanism for regulation of behaviour during approach avoidance conflict: through two specialized, parallel circuits that allow bidirectional hippocampal control of PFC.
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Affiliation(s)
- Candela Sánchez-Bellot
- Department of Neuroscience, Physiology and Pharmacology, University College London, Gower St, London, WC1E 6BT, UK
| | - Rawan AlSubaie
- Department of Neuroscience, Physiology and Pharmacology, University College London, Gower St, London, WC1E 6BT, UK
| | - Karyna Mishchanchuk
- Department of Neuroscience, Physiology and Pharmacology, University College London, Gower St, London, WC1E 6BT, UK
| | - Ryan W S Wee
- Department of Neuroscience, Physiology and Pharmacology, University College London, Gower St, London, WC1E 6BT, UK
| | - Andrew F MacAskill
- Department of Neuroscience, Physiology and Pharmacology, University College London, Gower St, London, WC1E 6BT, UK.
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6
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Vickstrom CR, Snarrenberg ST, Friedman V, Liu QS. Application of optogenetics and in vivo imaging approaches for elucidating the neurobiology of addiction. Mol Psychiatry 2022; 27:640-651. [PMID: 34145393 PMCID: PMC9190069 DOI: 10.1038/s41380-021-01181-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Accepted: 05/26/2021] [Indexed: 02/05/2023]
Abstract
The neurobiology of addiction has been an intense topic of investigation for more than 50 years. Over this time, technological innovation in methods for studying brain function rapidly progressed, leading to increasingly sophisticated experimental approaches. To understand how specific brain regions, cell types, and circuits are affected by drugs of abuse and drive behaviors characteristic of addiction, it is necessary both to observe and manipulate neural activity in addiction-related behavioral paradigms. In pursuit of this goal, there have been several key technological advancements in in vivo imaging and neural circuit modulation in recent years, which have shed light on the cellular and circuit mechanisms of addiction. Here we discuss some of these key technologies, including circuit modulation with optogenetics, in vivo imaging with miniaturized single-photon microscopy (miniscope) and fiber photometry, and how the application of these technologies has garnered novel insights into the neurobiology of addiction.
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7
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Maes ME, Wögenstein GM, Colombo G, Casado-Polanco R, Siegert S. Optimizing AAV2/6 microglial targeting identified enhanced efficiency in the photoreceptor degenerative environment. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2021; 23:210-224. [PMID: 34703843 PMCID: PMC8516996 DOI: 10.1016/j.omtm.2021.09.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Accepted: 09/07/2021] [Indexed: 12/13/2022]
Abstract
Adeno-associated viruses (AAVs) are widely used to deliver genetic material in vivo to distinct cell types such as neurons or glial cells, allowing for targeted manipulation. Transduction of microglia is mostly excluded from this strategy, likely due to the cells’ heterogeneous state upon environmental changes, which makes AAV design challenging. Here, we established the retina as a model system for microglial AAV validation and optimization. First, we show that AAV2/6 transduced microglia in both synaptic layers, where layer preference corresponds to the intravitreal or subretinal delivery method. Surprisingly, we observed significantly enhanced microglial transduction during photoreceptor degeneration. Thus, we modified the AAV6 capsid to reduce heparin binding by introducing four point mutations (K531E, R576Q, K493S, and K459S), resulting in increased microglial transduction in the outer plexiform layer. Finally, to improve microglial-specific transduction, we validated a Cre-dependent transgene delivery cassette for use in combination with the Cx3cr1CreERT2 mouse line. Together, our results provide a foundation for future studies optimizing AAV-mediated microglia transduction and highlight that environmental conditions influence microglial transduction efficiency.
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Affiliation(s)
- Margaret E Maes
- Institute of Science and Technology (IST) Austria, 3400 Klosterneuburg, Austria
| | | | - Gloria Colombo
- Institute of Science and Technology (IST) Austria, 3400 Klosterneuburg, Austria
| | | | - Sandra Siegert
- Institute of Science and Technology (IST) Austria, 3400 Klosterneuburg, Austria
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8
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Botterill JJ, Khlaifia A, Walters BJ, Brimble MA, Scharfman HE, Arruda-Carvalho M. Off-Target Expression of Cre-Dependent Adeno-Associated Viruses in Wild-Type C57BL/6J Mice. eNeuro 2021; 8:ENEURO.0363-21.2021. [PMID: 34785571 PMCID: PMC8614227 DOI: 10.1523/eneuro.0363-21.2021] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Revised: 10/26/2021] [Accepted: 10/29/2021] [Indexed: 11/21/2022] Open
Abstract
Adeno-associated viruses (AAVs) are a commonly used tool in neuroscience to efficiently label, trace, and/or manipulate neuronal populations. Highly specific targeting can be achieved through recombinase-dependent AAVs in combination with transgenic rodent lines that express Cre-recombinase in specific cell types. Visualization of viral expression is typically achieved through fluorescent reporter proteins (e.g., GFP or mCherry) packaged within the AAV genome. Although nonamplified fluorescence is usually sufficient to observe viral expression, immunohistochemical amplification of the fluorescent reporter is routinely used to improve viral visualization. In the present study, Cre-dependent AAVs were injected into the neocortex of wild-type C57BL/6J mice. While we observed weak but consistent nonamplified off-target double inverted open reading frame (DIO) expression in C57BL/6J mice, antibody amplification of the GFP or mCherry reporter revealed notable Cre-independent viral expression. Off-target expression of DIO constructs in wild-type C57BL/6J mice occurred independent of vendor, AAV serotype, or promoter. We also evaluated whether Cre-independent expression had functional effects via designer receptors exclusively activated by designer drugs (DREADDs). The DREADD agonist C21 (compound 21) had no effect on contextual fear conditioning or c-Fos expression in DIO-hM3Dq-mCherry+ cells of C57BL/6J mice. Together, our results indicate that DIO constructs have off-target expression in wild-type subjects. Our findings are particularly important for the design of experiments featuring sensitive systems and/or quantitative measurements that could be negatively impacted by off-target expression.
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Affiliation(s)
- Justin J Botterill
- Department of Psychology, University of Toronto Scarborough, Toronto, Ontario M1C 1A4, Canada
| | - Abdessattar Khlaifia
- Department of Psychology, University of Toronto Scarborough, Toronto, Ontario M1C 1A4, Canada
| | - Brandon J Walters
- Department of Cell & Systems Biology, University of Toronto Mississauga, Mississauga, Ontario L5L 1C6, Canada
| | - Mark A Brimble
- Department of Surgery, St. Jude Children's Research Hospital, Memphis, Tennnessee 38105
| | - Helen E Scharfman
- Center for Dementia Research, The Nathan Kline Institute for Psychiatric Research, Orangeburg, New York 10962
- Departments of Child & Adolescent Psychiatry, Neuroscience & Physiology, and Psychiatry, and New York University Neuroscience Institute, New York University Langone Health, New York, New York 10016
| | - Maithe Arruda-Carvalho
- Department of Psychology, University of Toronto Scarborough, Toronto, Ontario M1C 1A4, Canada
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario M5S 3G5, Canada
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9
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Cardenas A, Papadogiannis A, Dimitrov E. The role of medial prefrontal cortex projections to locus ceruleus in mediating the sex differences in behavior in mice with inflammatory pain. FASEB J 2021; 35:e21747. [PMID: 34151467 DOI: 10.1096/fj.202100319rr] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 05/27/2021] [Accepted: 06/07/2021] [Indexed: 11/11/2022]
Abstract
We tested the hypothesis that the cognitive impairment associated with inflammatory pain may result from dysregulation of the top-down control of locus ceruleus's (LC) activity by the medial prefrontal cortex (mPFC). Injection of complete Freund's adjuvant (CFA) served as a model for inflammatory pain. The CFA injection decreased the thermal thresholds in both sexes but only the male mice showed increased anxiety-like behavior and diminished cognition, while the females were not affected. Increased calcium fluorescence, a marker for neuronal activity, was detected by photometry in the mPFC of males but not in females with CFA. Next, while chemogenetic inhibition of the projections from the mPFC to the LC improved the object recognition memory of males with pain, the inhibition of the mPFC to LC pathway in female mice produced anxiolysis and spatial memory deficits. The behavior results prompted us to compare the reciprocal innervation of mPFC and LC between the sexes. We used an anterograde transsynaptic tagging technique, which relies on postsynaptic cre transfer, to assess the innervation of LC by mPFC efferents. The males showed a higher rate of postsynaptic cre transfer into LC neurons from mPFC efferents than the females. And vice versa, a retrograde tracing experiment demonstrated that LC to mPFC projection neurons were more numerous in females when compared to males. In conclusion, we provide evidence that subtle differences in the reciprocal neuronal circuit between the LC and mPFC may contribute to sex differences associated with the adverse cognitive effects of inflammatory pain.
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Affiliation(s)
- Andrea Cardenas
- Center for the Neurobiology of Stress Resilience and Psychiatric Disorders, Rosalind Franklin University of Medicine and Science, North Chicago, IL, USA
| | - Alexander Papadogiannis
- Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, IL, USA
| | - Eugene Dimitrov
- Center for the Neurobiology of Stress Resilience and Psychiatric Disorders, Rosalind Franklin University of Medicine and Science, North Chicago, IL, USA
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10
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Chadney OMT, Blankvoort S, Grimstvedt JS, Utz A, Kentros CG. Multiplexing viral approaches to the study of the neuronal circuits. J Neurosci Methods 2021; 357:109142. [PMID: 33753126 DOI: 10.1016/j.jneumeth.2021.109142] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 02/27/2021] [Accepted: 03/10/2021] [Indexed: 12/16/2022]
Abstract
Neural circuits are composed of multitudes of elaborately interconnected cell types. Understanding neural circuit function requires not only cell-specific knowledge of connectivity, but the ability to record and manipulate distinct cell types independently. Recent advances in viral vectors promise the requisite specificity to perform true "circuit-breaking" experiments. However, such new avenues of multiplexed, cell-specific investigation raise new technical issues: one must ensure that both the viral vectors and their transgene payloads do not overlap with each other in both an anatomical and a functional sense. This review describes benefits and issues regarding the use of viral vectors to analyse the function of neural circuits and provides a resource for the design and implementation of such multiplexing experiments.
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Affiliation(s)
- Oscar M T Chadney
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, NTNU, Trondheim, Norway.
| | - Stefan Blankvoort
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, NTNU, Trondheim, Norway
| | - Joachim S Grimstvedt
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, NTNU, Trondheim, Norway
| | - Annika Utz
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, NTNU, Trondheim, Norway
| | - Clifford G Kentros
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, NTNU, Trondheim, Norway.
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11
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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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12
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Duarte Azevedo M, Sander S, Jeanneret C, Olfat S, Tenenbaum L. Selective targeting of striatal parvalbumin-expressing interneurons for transgene delivery. J Neurosci Methods 2021; 354:109105. [PMID: 33652020 DOI: 10.1016/j.jneumeth.2021.109105] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 02/12/2021] [Accepted: 02/14/2021] [Indexed: 01/17/2023]
Abstract
PVCre mice--> combined with AAV-FLEX vectors allowed efficient and specific targeting of PV+ interneurons in the striatum. However, diffusion of viral particles to the globus pallidus caused massive transduction of PV+ projection neurons and subsequent anterograde transport of the transgene product to the subthalamic nucleus and the substantia nigra pars reticulata. Different AAV serotypes (1 and 9) and promoters (CBA and human synapsin) were evaluated. The combination of AAV1, a moderate expression level (human synapsin promoter) and a precise adjustment of the stereotaxic coordinates in the anterior and dorsolateral part of the striatum were necessary to avoid transduction of PV+ GP projection neurons. Even in the absence of direct transduction due to diffusion of viral particles, GP PV+ projection neurons could be retrogradely transduced via their terminals present in the dorsal striatum. However, in the absence of diffusion, GP-Str PV+ projection neurons were poorly or not transduced suggesting that retrograde transduction did not significantly impair the selective targeting of striatal PV+ neurons. Finally, a prominent reduction of the number of striatal PV+ interneurons (about 50 %) was evidenced in the presence of the Cre recombinase suggesting that functional effects of AAV-mediated transgene expression in PV+ striatal interneurons in PVCre mice should be analyzed with caution.
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Affiliation(s)
- Marcelo Duarte Azevedo
- Laboratory of Cellular and Molecular Neurotherapies, Center for Neuroscience Research, Clinical Neurosciences Department, Lausanne University Hospital, Switzerland
| | - Sibilla Sander
- Laboratory of Cellular and Molecular Neurotherapies, Center for Neuroscience Research, Clinical Neurosciences Department, Lausanne University Hospital, Switzerland
| | - Cheryl Jeanneret
- Laboratory of Cellular and Molecular Neurotherapies, Center for Neuroscience Research, Clinical Neurosciences Department, Lausanne University Hospital, Switzerland
| | - Soophie Olfat
- Laboratory of Cellular and Molecular Neurotherapies, Center for Neuroscience Research, Clinical Neurosciences Department, Lausanne University Hospital, Switzerland
| | - Liliane Tenenbaum
- Laboratory of Cellular and Molecular Neurotherapies, Center for Neuroscience Research, Clinical Neurosciences Department, Lausanne University Hospital, Switzerland.
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13
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Laing BT, Siemian JN, Sarsfield S, Aponte Y. Fluorescence microendoscopy for in vivo deep-brain imaging of neuronal circuits. J Neurosci Methods 2021; 348:109015. [PMID: 33259847 PMCID: PMC8745022 DOI: 10.1016/j.jneumeth.2020.109015] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 11/24/2020] [Accepted: 11/26/2020] [Indexed: 11/16/2022]
Abstract
Imaging neuronal activity in awake, behaving animals has become a groundbreaking method in neuroscience that has rapidly enhanced our understanding of how the brain works. In vivo microendoscopic imaging has enabled researchers to see inside the brains of experimental animals and thus has emerged as a technology fit to answer many experimental questions. By combining microendoscopy with cutting edge targeting strategies and sophisticated analysis tools, neuronal activity patterns that underlie changes in behavior and physiology can be identified. However, new users may find it challenging to understand the techniques and to leverage this technology to best suit their needs. Here we present a background and overview of the necessary components for performing in vivo optical calcium imaging and offer some detailed guidance for current recommended approaches.
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Affiliation(s)
- Brenton T Laing
- Neuronal Circuits and Behavior Unit, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD, 21224-6823, USA
| | - Justin N Siemian
- Neuronal Circuits and Behavior Unit, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD, 21224-6823, USA
| | - Sarah Sarsfield
- Neuronal Circuits and Behavior Unit, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD, 21224-6823, USA
| | - Yeka Aponte
- Neuronal Circuits and Behavior Unit, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD, 21224-6823, USA; The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
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14
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Wang YB, de Lartigue G, Page AJ. Dissecting the Role of Subtypes of Gastrointestinal Vagal Afferents. Front Physiol 2020; 11:643. [PMID: 32595525 PMCID: PMC7300233 DOI: 10.3389/fphys.2020.00643] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Accepted: 05/20/2020] [Indexed: 12/22/2022] Open
Abstract
Gastrointestinal (GI) vagal afferents convey sensory signals from the GI tract to the brain. Numerous subtypes of GI vagal afferent have been identified but their individual roles in gut function and feeding regulation are unclear. In the past decade, technical approaches to selectively target vagal afferent subtypes and to assess their function has significantly progressed. This review examines the classification of GI vagal afferent subtypes and discusses the current available techniques to study vagal afferents. Investigating the distribution of GI vagal afferent subtypes and understanding how to access and modulate individual populations are essential to dissect their fundamental roles in the gut-brain axis.
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Affiliation(s)
- Yoko B Wang
- Vagal Afferent Research Group, Adelaide Medical School, The University of Adelaide, Adelaide, SA, Australia
| | - Guillaume de Lartigue
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL, United States.,Center for Integrative Cardiovascular and Metabolic Disease, University of Florida, Gainesville, FL, United States
| | - Amanda J Page
- Vagal Afferent Research Group, Adelaide Medical School, The University of Adelaide, Adelaide, SA, Australia.,Nutrition, Diabetes and Gut Health, Lifelong Health Theme, South Australian Health and Medical Research Institute, Adelaide, SA, Australia
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15
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Maes ME, Colombo G, Schulz R, Siegert S. Targeting microglia with lentivirus and AAV: Recent advances and remaining challenges. Neurosci Lett 2019; 707:134310. [PMID: 31158432 PMCID: PMC6734419 DOI: 10.1016/j.neulet.2019.134310] [Citation(s) in RCA: 78] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 05/30/2019] [Indexed: 02/06/2023]
Abstract
Microglia have emerged as a critical component of neurodegenerative diseases. Genetic manipulation of microglia can elucidate their functional impact in disease. In neuroscience, recombinant viruses such as lentiviruses and adeno-associated viruses (AAVs) have been successfully used to target various cell types in the brain, although effective transduction of microglia is rare. In this review, we provide a short background of lentiviruses and AAVs, and strategies for designing recombinant viral vectors. Then, we will summarize recent literature on successful microglial transductions in vitro and in vivo, and discuss the current challenges. Finally, we provide guidelines for reporting the efficiency and specificity of viral targeting in microglia, which will enable the microglial research community to assess and improve methodologies for future studies.
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Affiliation(s)
- Margaret E Maes
- Institute of Science and Technology (IST) Austria, Am Campus 1, 3400 Klosterneuburg, Austria
| | - Gloria Colombo
- Institute of Science and Technology (IST) Austria, Am Campus 1, 3400 Klosterneuburg, Austria
| | - Rouven Schulz
- Institute of Science and Technology (IST) Austria, Am Campus 1, 3400 Klosterneuburg, Austria
| | - Sandra Siegert
- Institute of Science and Technology (IST) Austria, Am Campus 1, 3400 Klosterneuburg, Austria.
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16
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Considerations for the use of virally delivered genetic tools for in-vivo circuit analysis and behavior in mutant mice: a practical guide to optogenetics. Behav Pharmacol 2018; 28:598-609. [PMID: 29099403 DOI: 10.1097/fbp.0000000000000361] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Optogenetics was the method of the year in 2010 according to Nature Neuroscience. Since then, this method has become widespread, the use of virally delivered genetic tools has extended to other fields such as pharmacogenetics, and optogenetic techniques have become frequently applied in genetically manipulated animals for in-vivo circuit analysis and behavioral studies. However, several issues should be taken into consideration when planning such experiments. We aimed to summarize the critical points concerning optogenetic manipulation of a specific brain area in mutant mice. First, the appropriate vector should be chosen to allow optimal optogenetic manipulation. Adeno-associated viral vectors are the most common carriers with different available serotypes. Light-sensitive channels are available in many forms, and the expression of the delivered genetic material can be influenced in many ways. Second, selecting the adequate stimulation protocol is also essential. The pattern, intensity, and timing could be determinative parameters. Third, the mutant strain might have a phenotype that influences the observed behavior. In conclusion, detailed preliminary experiments and numerous control groups are required to choose the best vector and stimulation protocol and to ensure that the mutant animals do not have a specific phenotype that can influence the examined behavior.
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17
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Gallo EF, Meszaros J, Sherman JD, Chohan MO, Teboul E, Choi CS, Moore H, Javitch JA, Kellendonk C. Accumbens dopamine D2 receptors increase motivation by decreasing inhibitory transmission to the ventral pallidum. Nat Commun 2018; 9:1086. [PMID: 29540712 PMCID: PMC5852096 DOI: 10.1038/s41467-018-03272-2] [Citation(s) in RCA: 76] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Accepted: 02/01/2018] [Indexed: 12/04/2022] Open
Abstract
Dopamine D2 receptors (D2Rs) in the nucleus accumbens (NAc) regulate motivated behavior, but the underlying neurobiological mechanisms remain unresolved. Here, we show that selective upregulation of D2Rs in the indirect pathway of the adult NAc enhances the willingness to work for food. Mechanistic studies in brain slices reveal that D2R upregulation attenuates inhibitory transmission at two main output projections of the indirect pathway, the classical long-range projections to the ventral pallidum (VP), as well as local collaterals to direct pathway medium spiny neurons. In vivo physiology confirms the reduction in indirect pathway inhibitory transmission to the VP, and inhibition of indirect pathway terminals to VP is sufficient to enhance motivation. In contrast, D2R upregulation in the indirect pathway does not disinhibit neuronal activity of the direct pathway in vivo. These data suggest that D2Rs in ventral striatal projection neurons promote motivation by weakening the canonical output to the ventral pallidum.
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Affiliation(s)
- Eduardo F Gallo
- Department of Psychiatry, College of Physicians and Surgeons, Columbia University, New York, NY, 10032, USA
- Division of Molecular Therapeutics, New York State Psychiatric Institute, New York, NY, 10032, USA
| | - Jozsef Meszaros
- Division of Molecular Therapeutics, New York State Psychiatric Institute, New York, NY, 10032, USA
| | - Jeremy D Sherman
- Department of Psychiatry, College of Physicians and Surgeons, Columbia University, New York, NY, 10032, USA
- Division of Molecular Therapeutics, New York State Psychiatric Institute, New York, NY, 10032, USA
| | - Muhammad O Chohan
- Division of Integrative Neuroscience, New York State Psychiatric Institute, New York, NY, 10032, USA
| | - Eric Teboul
- Department of Psychiatry, College of Physicians and Surgeons, Columbia University, New York, NY, 10032, USA
- Division of Molecular Therapeutics, New York State Psychiatric Institute, New York, NY, 10032, USA
| | - Claire S Choi
- Department of Psychiatry, College of Physicians and Surgeons, Columbia University, New York, NY, 10032, USA
- Division of Molecular Therapeutics, New York State Psychiatric Institute, New York, NY, 10032, USA
| | - Holly Moore
- Department of Psychiatry, College of Physicians and Surgeons, Columbia University, New York, NY, 10032, USA
- Division of Integrative Neuroscience, New York State Psychiatric Institute, New York, NY, 10032, USA
| | - Jonathan A Javitch
- Department of Psychiatry, College of Physicians and Surgeons, Columbia University, New York, NY, 10032, USA
- Division of Molecular Therapeutics, New York State Psychiatric Institute, New York, NY, 10032, USA
- Department of Pharmacology, College of Physicians and Surgeons, Columbia University, New York, NY, 10032, USA
| | - Christoph Kellendonk
- Department of Psychiatry, College of Physicians and Surgeons, Columbia University, New York, NY, 10032, USA.
- Division of Molecular Therapeutics, New York State Psychiatric Institute, New York, NY, 10032, USA.
- Department of Pharmacology, College of Physicians and Surgeons, Columbia University, New York, NY, 10032, USA.
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18
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Anastasiades PG, Marques‐Smith A, Butt SJB. Studies of cortical connectivity using optical circuit mapping methods. J Physiol 2018; 596:145-162. [PMID: 29110301 PMCID: PMC5767689 DOI: 10.1113/jp273463] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Accepted: 10/11/2017] [Indexed: 11/08/2022] Open
Abstract
An important consideration when probing the function of any neuron is to uncover the source of synaptic input onto the cell, its intrinsic physiology and efferent targets. Over the years, electrophysiological approaches have generated considerable insight into these properties in a variety of cortical neuronal subtypes and circuits. However, as researchers explore neuronal function in greater detail, they are increasingly turning to optical techniques to bridge the gap between local network interactions and behaviour. The application of optical methods has increased dramatically over the past decade, spurred on by the optogenetic revolution. In this review, we provide an account of recent innovations, providing researchers with a primer detailing circuit mapping strategies in the cerebral cortex. We will focus on technical aspects of performing neurotransmitter uncaging and channelrhodopsin-assisted circuit mapping, with the aim of identifying common pitfalls that can negatively influence the collection of reliable data.
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19
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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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20
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Treweek JB, Gradinaru V. Extracting structural and functional features of widely distributed biological circuits with single cell resolution via tissue clearing and delivery vectors. Curr Opin Biotechnol 2016; 40:193-207. [PMID: 27393829 DOI: 10.1016/j.copbio.2016.03.012] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Revised: 03/10/2016] [Accepted: 03/15/2016] [Indexed: 12/13/2022]
Abstract
The scientific community has learned a great deal from imaging small and naturally transparent organisms such as nematodes and zebrafish. The consequences of genetic mutations on their organ development and survival can be visualized easily and with high-throughput at the organism-wide scale. In contrast, three-dimensional information is less accessible in mammalian subjects because the heterogeneity of light-scattering tissue elements renders their organs opaque. Likewise, genetically labeling desired circuits across mammalian bodies is prohibitively slow and costly via the transgenic route. Emerging breakthroughs in viral vector engineering, genome editing tools, and tissue clearing can render larger opaque organisms genetically tractable and transparent for whole-organ cell phenotyping, tract tracing and imaging at depth.
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Affiliation(s)
- Jennifer Brooke Treweek
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Viviana Gradinaru
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA.
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