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Hariani HN, Algstam AB, Candler CT, Witteveen IF, Sidhu JK, Balmer TS. A system of feed-forward cerebellar circuits that extend and diversify sensory signaling. eLife 2024; 12:RP88321. [PMID: 38270517 PMCID: PMC10945699 DOI: 10.7554/elife.88321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2024] Open
Abstract
Sensory signals are processed by the cerebellum to coordinate movements. Numerous cerebellar functions are thought to require the maintenance of a sensory representation that extends beyond the input signal. Granule cells receive sensory input, but they do not prolong the signal and are thus unlikely to maintain a sensory representation for much longer than the inputs themselves. Unipolar brush cells (UBCs) are excitatory interneurons that project to granule cells and transform sensory input into prolonged increases or decreases in firing, depending on their ON or OFF UBC subtype. Further extension and diversification of the input signal could be produced by UBCs that project to one another, but whether this circuitry exists is unclear. Here we test whether UBCs innervate one another and explore how these small networks of UBCs could transform spiking patterns. We characterized two transgenic mouse lines electrophysiologically and immunohistochemically to confirm that they label ON and OFF UBC subtypes and crossed them together, revealing that ON and OFF UBCs innervate one another. A Brainbow reporter was used to label UBCs of the same ON or OFF subtype with different fluorescent proteins, which showed that UBCs innervate their own subtypes as well. Computational models predict that these feed-forward networks of UBCs extend the length of bursts or pauses and introduce delays-transformations that may be necessary for cerebellar functions from modulation of eye movements to adaptive learning across time scales.
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Affiliation(s)
- Harsh N Hariani
- Interdisciplinary Graduate Program in Neuroscience, Arizona State UniversityTempeUnited States
- School of Life Sciences, Arizona State UniversityTempeUnited States
| | - A Brynn Algstam
- School of Life Sciences, Arizona State UniversityTempeUnited States
- Barrett Honors College, Arizona State UniversityTempeUnited States
| | - Christian T Candler
- Interdisciplinary Graduate Program in Neuroscience, Arizona State UniversityTempeUnited States
- School of Life Sciences, Arizona State UniversityTempeUnited States
| | | | - Jasmeen K Sidhu
- School of Life Sciences, Arizona State UniversityTempeUnited States
| | - Timothy S Balmer
- School of Life Sciences, Arizona State UniversityTempeUnited States
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2
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Hariani HN, Algstam AB, Candler CT, Witteveen IF, Sidhu JK, Balmer TS. A system of feed-forward cerebellar circuits that extend and diversify sensory signaling. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.11.536335. [PMID: 37090638 PMCID: PMC10120650 DOI: 10.1101/2023.04.11.536335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/25/2023]
Abstract
Sensory signals are processed by the cerebellum to coordinate movements. Numerous cerebellar functions are thought to require the maintenance of a sensory representation that extends beyond the input signal. Granule cells receive sensory input, but they do not prolong the signal and are thus unlikely to maintain a sensory representation for much longer than the inputs themselves. Unipolar brush cells (UBCs) are excitatory interneurons that project to granule cells and transform sensory input into prolonged increases or decreases in firing, depending on their ON or OFF UBC subtype. Further extension and diversification of the input signal could be produced by UBCs that project to one another, but whether this circuitry exists is unclear. Here we test whether UBCs innervate one another and explore how these small networks of UBCs could transform spiking patterns. We characterized two transgenic mouse lines electrophysiologically and immunohistochemically to confirm that they label ON and OFF UBC subtypes and crossed them together, revealing that ON and OFF UBCs innervate one another. A Brainbow reporter was used to label UBCs of the same ON or OFF subtype with different fluorescent proteins, which showed that UBCs innervate their own subtypes as well. Computational models predict that these feed-forward networks of UBCs extend the length of bursts or pauses and introduce delays-transformations that may be necessary for cerebellar functions from modulation of eye movements to adaptive learning across time scales.
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Affiliation(s)
- Harsh N. Hariani
- Interdisciplinary Graduate Program in Neuroscience
- School of Life Sciences, Arizona State University, Tempe, AZ, 85287
| | - A. Brynn Algstam
- Barrett Honors College
- School of Life Sciences, Arizona State University, Tempe, AZ, 85287
| | - Christian T. Candler
- Interdisciplinary Graduate Program in Neuroscience
- School of Life Sciences, Arizona State University, Tempe, AZ, 85287
| | | | - Jasmeen K. Sidhu
- School of Life Sciences, Arizona State University, Tempe, AZ, 85287
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3
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Han M, Perkins MH, Novaes LS, Xu T, Chang H. Advances in transposable elements: from mechanisms to applications in mammalian genomics. Front Genet 2023; 14:1290146. [PMID: 38098473 PMCID: PMC10719622 DOI: 10.3389/fgene.2023.1290146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Accepted: 11/13/2023] [Indexed: 12/17/2023] Open
Abstract
It has been 70 years since Barbara McClintock discovered transposable elements (TE), and the mechanistic studies and functional applications of transposable elements have been at the forefront of life science research. As an essential part of the genome, TEs have been discovered in most species of prokaryotes and eukaryotes, and the relative proportion of the total genetic sequence they comprise gradually increases with the expansion of the genome. In humans, TEs account for about 40% of the genome and are deeply involved in gene regulation, chromosome structure maintenance, inflammatory response, and the etiology of genetic and non-genetic diseases. In-depth functional studies of TEs in mammalian cells and the human body have led to a greater understanding of these fundamental biological processes. At the same time, as a potent mutagen and efficient genome editing tool, TEs have been transformed into biological tools critical for developing new techniques. By controlling the random insertion of TEs into the genome to change the phenotype in cells and model organisms, critical proteins of many diseases have been systematically identified. Exploiting the TE's highly efficient in vitro insertion activity has driven the development of cutting-edge sequencing technologies. Recently, a new technology combining CRISPR with TEs was reported, which provides a novel targeted insertion system to both academia and industry. We suggest that interrogating biological processes that generally depend on the actions of TEs with TEs-derived genetic tools is a very efficient strategy. For example, excessive activation of TEs is an essential factor in the occurrence of cancer in humans. As potent mutagens, TEs have also been used to unravel the key regulatory elements and mechanisms of carcinogenesis. Through this review, we aim to effectively combine the traditional views of TEs with recent research progress, systematically link the mechanistic discoveries of TEs with the technological developments of TE-based tools, and provide a comprehensive approach and understanding for researchers in different fields.
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Affiliation(s)
- Mei Han
- Guangzhou National Laboratory, Guangzhou, China
| | - Matthew H. Perkins
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Leonardo Santana Novaes
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Tao Xu
- Guangzhou National Laboratory, Guangzhou, China
| | - Hao Chang
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, United States
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4
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Li L, Liu Z. Genetic Approaches for Neural Circuits Dissection in Non-human Primates. Neurosci Bull 2023; 39:1561-1576. [PMID: 37258795 PMCID: PMC10533465 DOI: 10.1007/s12264-023-01067-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Accepted: 03/27/2023] [Indexed: 06/02/2023] Open
Abstract
Genetic tools, which can be used for the morphology study of specific neurons, pathway-selective connectome mapping, neuronal activity monitoring, and manipulation with a spatiotemporal resolution, have been widely applied to the understanding of complex neural circuit formation, interactions, and functions in rodents. Recently, similar genetic approaches have been tried in non-human primates (NHPs) in neuroscience studies for dissecting the neural circuits involved in sophisticated behaviors and clinical brain disorders, although they are still very preliminary. In this review, we introduce the progress made in the development and application of genetic tools for brain studies on NHPs. We also discuss the advantages and limitations of each approach and provide a perspective for using genetic tools to study the neural circuits of NHPs.
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Affiliation(s)
- Ling Li
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, CAS Key Laboratory of Primate Neurobiology, State Key Laboratory of Neuroscience, Chinese Academy of Sciences, Shanghai, 200031, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhen Liu
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, CAS Key Laboratory of Primate Neurobiology, State Key Laboratory of Neuroscience, Chinese Academy of Sciences, Shanghai, 200031, China.
- Shanghai Center for Brain Science and Brain-Inspired Intelligence Technology, Shanghai, 200031, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
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5
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Marron AO, Sauret‐Güeto S, Rebmann M, Silvestri L, Tomaselli M, Haseloff J. An enhancer trap system to track developmental dynamics in Marchantia polymorpha. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2023; 116:604-628. [PMID: 37583263 PMCID: PMC10952768 DOI: 10.1111/tpj.16394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 07/05/2023] [Accepted: 07/10/2023] [Indexed: 08/17/2023]
Abstract
A combination of streamlined genetics, experimental tractability and relative morphological simplicity compared to vascular plants makes the liverwort Marchantia polymorpha an ideal model system for studying many aspects of plant biology. Here we describe a transformation vector combining a constitutive fluorescent membrane marker with a nuclear marker that is regulated by nearby enhancer elements and use this to produce a library of enhancer trap lines for Marchantia. Screening gemmae from these lines allowed the identification and characterization of novel marker lines, including markers for rhizoids and oil cells. The library allowed the identification of a margin tissue running around the thallus edge, highlighted during thallus development. The expression of this marker is correlated with auxin levels. We generated multiple markers for the meristematic apical notch region, which have different spatial expression patterns, reappear at different times during meristem regeneration following apical notch excision and have varying responses to auxin supplementation or inhibition. This reveals that there are proximodistal substructures within the apical notch that could not be observed otherwise. We employed our markers to study Marchantia sporeling development, observing meristem emergence as defining the protonema-to-prothallus stage transition, and subsequent production of margin tissue during the prothallus stage. Exogenous auxin treatment stalls meristem emergence at the protonema stage but does not inhibit cell division, resulting in callus-like sporelings with many rhizoids, whereas pharmacologically inhibiting auxin synthesis and transport does not prevent meristem emergence. This enhancer trap system presents a useful resource for the community and will contribute to future Marchantia research.
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Affiliation(s)
- Alan O. Marron
- Department of Plant SciencesUniversity of CambridgeDowning StreetCambridgeCB2 3EAUK
| | - Susanna Sauret‐Güeto
- Department of Plant SciencesUniversity of CambridgeDowning StreetCambridgeCB2 3EAUK
- Present address:
Crop Science CentreUniversity of Cambridge93 Lawrence Weaver, RoadCambridgeCB3 0LEUK
| | - Marius Rebmann
- Department of Plant SciencesUniversity of CambridgeDowning StreetCambridgeCB2 3EAUK
| | - Linda Silvestri
- Department of Plant SciencesUniversity of CambridgeDowning StreetCambridgeCB2 3EAUK
| | - Marta Tomaselli
- Department of Plant SciencesUniversity of CambridgeDowning StreetCambridgeCB2 3EAUK
| | - Jim Haseloff
- Department of Plant SciencesUniversity of CambridgeDowning StreetCambridgeCB2 3EAUK
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Carrell EM, Chen YH, Ranum PT, Coffin SL, Singh LN, Tecedor L, Keiser MS, Hudry E, Hyman BT, Davidson BL. VWA3A-derived ependyma promoter drives increased therapeutic protein secretion into the CSF. MOLECULAR THERAPY. NUCLEIC ACIDS 2023; 33:296-304. [PMID: 37547292 PMCID: PMC10400871 DOI: 10.1016/j.omtn.2023.07.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 07/12/2023] [Indexed: 08/08/2023]
Abstract
Recombinant adeno-associated viral vectors (rAAVs) are a promising strategy to treat neurodegenerative diseases because of their ability to infect non-dividing cells and confer long-term transgene expression. Despite an ever-growing library of capsid variants, widespread delivery of AAVs in the adult central nervous system remains a challenge. We have previously demonstrated successful distribution of secreted proteins by infection of the ependyma, a layer of post-mitotic epithelial cells lining the ventricles of the brain and central column of the spinal cord, and subsequent protein delivery via the cerebrospinal fluid (CSF). Here we define a functional ependyma promoter to enhance expression from this cell type. Using RNA sequencing on human autopsy samples, we identified disease- and age-independent ependyma gene signatures. Associated promoters were cloned and screened as libraries in mouse and rhesus macaque to reveal cross-species function of a human DNA-derived von Willebrand factor domain containing 3A (VWA3A) promoter. When tested in mice, our VWA3A promoter drove strong, ependyma-localized expression of eGFP and increased secreted ApoE protein levels in the CSF by 2-12× over the ubiquitous iCAG promoter.
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Affiliation(s)
- Ellie M. Carrell
- Raymond G. Perelman Center for Cellular and Molecular Therapeutics, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Yong Hong Chen
- Raymond G. Perelman Center for Cellular and Molecular Therapeutics, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Paul T. Ranum
- Raymond G. Perelman Center for Cellular and Molecular Therapeutics, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Stephanie L. Coffin
- Raymond G. Perelman Center for Cellular and Molecular Therapeutics, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Larry N. Singh
- Center for Mitochondrial and Epigenomic Medicine, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Luis Tecedor
- Raymond G. Perelman Center for Cellular and Molecular Therapeutics, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Megan S. Keiser
- Raymond G. Perelman Center for Cellular and Molecular Therapeutics, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Eloise Hudry
- Department of Neurology, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Bradley T. Hyman
- Department of Neurology, Massachusetts General Hospital, Boston, MA 02114, USA
- Massachusetts Alzheimer’s Disease Research Center, Charlestown, MA 02129, USA
- Harvard Medical School, Boston, MA 02115, USA
| | - Beverly L. Davidson
- Raymond G. Perelman Center for Cellular and Molecular Therapeutics, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
- Department of Pathology & Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
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7
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Davis W, Endo M, Locke JCW. Spatially specific mechanisms and functions of the plant circadian clock. PLANT PHYSIOLOGY 2022; 190:938-951. [PMID: 35640123 PMCID: PMC9516738 DOI: 10.1093/plphys/kiac236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Accepted: 04/22/2022] [Indexed: 06/15/2023]
Abstract
Like many organisms, plants have evolved a genetic network, the circadian clock, to coordinate processes with day/night cycles. In plants, the clock is a pervasive regulator of development and modulates many aspects of physiology. Clock-regulated processes range from the correct timing of growth and cell division to interactions with the root microbiome. Recently developed techniques, such as single-cell time-lapse microscopy and single-cell RNA-seq, are beginning to revolutionize our understanding of this clock regulation, revealing a surprising degree of organ, tissue, and cell-type specificity. In this review, we highlight recent advances in our spatial view of the clock across the plant, both in terms of how it is regulated and how it regulates a diversity of output processes. We outline how understanding these spatially specific functions will help reveal the range of ways that the clock provides a fitness benefit for the plant.
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Affiliation(s)
- William Davis
- Sainsbury Laboratory, University of Cambridge, Cambridge, UK
| | - Motomu Endo
- Authors for correspondence: (M.E.); (J.C.W.L.)
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8
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The Annotation of Zebrafish Enhancer Trap Lines Generated with PB Transposon. Curr Issues Mol Biol 2022; 44:2614-2621. [PMID: 35735619 PMCID: PMC9221761 DOI: 10.3390/cimb44060178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 05/30/2022] [Accepted: 05/31/2022] [Indexed: 11/16/2022] Open
Abstract
An enhancer trap (ET) mediated by a transposon is an effective method for functional gene research. Here, an ET system based on a PB transposon that carries a mini Krt4 promoter (the keratin4 minimal promoter from zebrafish) and the green fluorescent protein gene (GFP) has been used to produce zebrafish ET lines. One enhancer trap line with eye-specific expression GFP named EYE was used to identify the trapped enhancers and genes. Firstly, GFP showed a temporal and spatial expression pattern with whole-embryo expression at 6, 12, and 24 hpf stages and eye-specific expression from 2 to 7 dpf. Then, the genome insertion sites were detected by splinkerette PCR (spPCR). The Krt4-GFP was inserted into the fourth intron of the gene itgav (integrin, alpha V) in chromosome 9 of the zebrafish genome, with the GFP direction the same as that of the itgav gene. By the alignment of homologous gene sequences in different species, three predicted endogenous enhancers were obtained. The trapped endogenous gene itgav, whose overexpression is related to hepatocellular carcinoma, showed a similar expression pattern as GFP detected by in situ hybridization, which suggested that GFP and itgav were possibly regulated by the same enhancers. In short, the zebrafish enhancer trap lines generated by the PB transposon-mediated enhancer trap technology in this study were valuable resources as visual markers to study the regulators and genes. This work provides an efficient method to identify and isolate tissue-specific enhancer sequences.
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9
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Cannabinoid Receptor 1 Is Required for Neurodevelopment of Striosome-Dendron Bouquets. eNeuro 2022; 9:ENEURO.0318-21.2022. [PMID: 35361667 PMCID: PMC9007419 DOI: 10.1523/eneuro.0318-21.2022] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 03/10/2022] [Accepted: 03/16/2022] [Indexed: 11/21/2022] Open
Abstract
Cannabinoid receptor 1 (CB1R) has strong effects on neurogenesis and axon pathfinding in the prenatal brain. Endocannabinoids that activate CB1R are abundant in the early postnatal brain and in mother's milk, but few studies have investigated their function in newborns. We examined postnatal CB1R expression in the major striatonigral circuit from striosomes of the striatum to the dopamine-containing neurons of the substantia nigra. CB1R enrichment was first detectable between postnatal day (P)5 and P7, and this timing coincided with the formation of "striosome-dendron bouquets," the elaborate anatomic structures by which striosomal neurons control dopaminergic cell activity through inhibitory synapses. In Cnr1-/- knock-out mice lacking CB1R expression, striosome-dendron bouquets were markedly disorganized by P11 and at adulthood, suggesting a postnatal pathfinding connectivity function for CB1R in connecting striosomal axons and dopaminergic neurons analogous to CB1R's prenatal function in other brain regions. Our finding that CB1R plays a major role in postnatal wiring of the striatonigral dopamine-control system, with lasting consequences at least in mice, points to a crucial need to determine whether lactating mothers' use of CB1R agonists (e.g., in marijuana) or antagonists (e.g., type 2 diabetes therapies) can disrupt brain development in nursing offspring.
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10
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AAV capsid variants with brain-wide transgene expression and decreased liver targeting after intravenous delivery in mouse and marmoset. Nat Neurosci 2022; 25:106-115. [PMID: 34887588 DOI: 10.1038/s41593-021-00969-4] [Citation(s) in RCA: 117] [Impact Index Per Article: 58.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 10/22/2021] [Indexed: 11/09/2022]
Abstract
Genetic intervention is increasingly being explored as a therapeutic option for debilitating disorders of the central nervous system. The safety and efficacy of gene therapies rely upon expressing a transgene in affected cells while minimizing off-target expression. Here we show organ-specific targeting of adeno-associated virus (AAV) capsids after intravenous delivery, which we achieved by employing a Cre-transgenic-based screening platform and sequential engineering of AAV-PHP.eB between the surface-exposed AA452 and AA460 of VP3. From this selection, we identified capsid variants that were enriched in the brain and targeted away from the liver in C57BL/6J mice. This tropism extends to marmoset (Callithrix jacchus), enabling robust, non-invasive gene delivery to the marmoset brain after intravenous administration. Notably, the capsids identified result in distinct transgene expression profiles within the brain, with one exhibiting high specificity to neurons. The ability to cross the blood-brain barrier with neuronal specificity in rodents and non-human primates enables new avenues for basic research and therapeutic possibilities unattainable with naturally occurring serotypes.
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11
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In Search of Molecular Markers for Cerebellar Neurons. Int J Mol Sci 2021; 22:ijms22041850. [PMID: 33673348 PMCID: PMC7918299 DOI: 10.3390/ijms22041850] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 02/09/2021] [Accepted: 02/09/2021] [Indexed: 02/06/2023] Open
Abstract
The cerebellum, the region of the brain primarily responsible for motor coordination and balance, also contributes to non-motor functions, such as cognition, speech, and language comprehension. Maldevelopment and dysfunction of the cerebellum lead to cerebellar ataxia and may even be associated with autism, depression, and cognitive deficits. Hence, normal development of the cerebellum and its neuronal circuitry is critical for the cerebellum to function properly. Although nine major types of cerebellar neurons have been identified in the cerebellar cortex to date, the exact functions of each type are not fully understood due to a lack of cell-specific markers in neurons that renders cell-specific labeling and functional study by genetic manipulation unfeasible. The availability of cell-specific markers is thus vital for understanding the role of each neuronal type in the cerebellum and for elucidating the interactions between cell types within both the developing and mature cerebellum. This review discusses various technical approaches and recent progress in the search for cell-specific markers for cerebellar neurons.
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12
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Gerlei K, Passlack J, Hawes I, Vandrey B, Stevens H, Papastathopoulos I, Nolan MF. Grid cells are modulated by local head direction. Nat Commun 2020; 11:4228. [PMID: 32839445 PMCID: PMC7445272 DOI: 10.1038/s41467-020-17500-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Accepted: 07/02/2020] [Indexed: 01/11/2023] Open
Abstract
Grid and head direction codes represent cognitive spaces for navigation and memory. Pure grid cells generate grid codes that have been assumed to be independent of head direction, whereas conjunctive cells generate grid representations that are tuned to a single head direction. Here, we demonstrate that pure grid cells also encode head direction, but through distinct mechanisms. We show that individual firing fields of pure grid cells are tuned to multiple head directions, with the preferred sets of directions differing between fields. This local directional modulation is not predicted by previous continuous attractor or oscillatory interference models of grid firing but is accounted for by models in which pure grid cells integrate inputs from co-aligned conjunctive cells with firing rates that differ between their fields. We suggest that local directional signals from grid cells may contribute to downstream computations by decorrelating different points of view from the same location.
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Affiliation(s)
- Klara Gerlei
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, EH8 9XD, UK
| | - Jessica Passlack
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, EH8 9XD, UK
| | - Ian Hawes
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, EH8 9XD, UK
| | - Brianna Vandrey
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, EH8 9XD, UK
| | - Holly Stevens
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, EH8 9XD, UK
| | - Ioannis Papastathopoulos
- School of Mathematics, Maxwell Institute and Centre for Statistics, University of Edinburgh, Edinburgh, EH9 3FD, UK
- The Alan Turing Institute, 96 Euston Road, London, NW1 2DB, UK
| | - Matthew F Nolan
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, EH8 9XD, UK.
- Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh, EH8 9XD, UK.
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13
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Levitan D, Liu C, Yang T, Shima Y, Lin JY, Wachutka J, Marrero Y, Ali Marandi Ghoddousi R, da Veiga Beltrame E, Richter TA, Katz DB, Nelson SB. Deletion of Stk11 and Fos in mouse BLA projection neurons alters intrinsic excitability and impairs formation of long-term aversive memory. eLife 2020; 9:e61036. [PMID: 32779566 PMCID: PMC7445010 DOI: 10.7554/elife.61036] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 08/04/2020] [Indexed: 12/14/2022] Open
Abstract
Conditioned taste aversion (CTA) is a form of one-trial learning dependent on basolateral amygdala projection neurons (BLApn). Its underlying cellular and molecular mechanisms remain poorly understood. RNAseq from BLApn identified changes in multiple candidate learning-related transcripts including the expected immediate early gene Fos and Stk11, a master kinase of the AMP-related kinase pathway with important roles in growth, metabolism and development, but not previously implicated in learning. Deletion of Stk11 in BLApn blocked memory prior to training, but not following it and increased neuronal excitability. Conversely, BLApn had reduced excitability following CTA. BLApn knockout of a second learning-related gene, Fos, also increased excitability and impaired learning. Independently increasing BLApn excitability chemogenetically during CTA also impaired memory. STK11 and C-FOS activation were independent of one another. These data suggest key roles for Stk11 and Fos in CTA long-term memory formation, dependent at least partly through convergent action on BLApn intrinsic excitability.
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Affiliation(s)
- David Levitan
- Departments of Biology, Brandeis UniversityWalthamUnited States
| | - Chenghao Liu
- Departments of Biology, Brandeis UniversityWalthamUnited States
| | - Tracy Yang
- Departments of Biology, Brandeis UniversityWalthamUnited States
| | - Yasuyuki Shima
- Departments of Biology, Brandeis UniversityWalthamUnited States
| | - Jian-You Lin
- Departments of Psychology, Brandeis UniversityWalthamUnited States
- Volen Center for Complex Systems, Brandeis UniversityWalthamUnited States
| | - Joseph Wachutka
- Departments of Psychology, Brandeis UniversityWalthamUnited States
| | - Yasmin Marrero
- Departments of Psychology, Brandeis UniversityWalthamUnited States
| | | | | | - Troy A Richter
- Departments of Biology, Brandeis UniversityWalthamUnited States
| | - Donald B Katz
- Departments of Psychology, Brandeis UniversityWalthamUnited States
- Volen Center for Complex Systems, Brandeis UniversityWalthamUnited States
| | - Sacha B Nelson
- Departments of Biology, Brandeis UniversityWalthamUnited States
- Volen Center for Complex Systems, Brandeis UniversityWalthamUnited States
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14
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Wang Q, Ding SL, Li Y, Royall J, Feng D, Lesnar P, Graddis N, Naeemi M, Facer B, Ho A, Dolbeare T, Blanchard B, Dee N, Wakeman W, Hirokawa KE, Szafer A, Sunkin SM, Oh SW, Bernard A, Phillips JW, Hawrylycz M, Koch C, Zeng H, Harris JA, Ng L. The Allen Mouse Brain Common Coordinate Framework: A 3D Reference Atlas. Cell 2020; 181:936-953.e20. [PMID: 32386544 PMCID: PMC8152789 DOI: 10.1016/j.cell.2020.04.007] [Citation(s) in RCA: 489] [Impact Index Per Article: 122.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Revised: 12/12/2019] [Accepted: 04/03/2020] [Indexed: 01/25/2023]
Abstract
Recent large-scale collaborations are generating major surveys of cell types and connections in the mouse brain, collecting large amounts of data across modalities, spatial scales, and brain areas. Successful integration of these data requires a standard 3D reference atlas. Here, we present the Allen Mouse Brain Common Coordinate Framework (CCFv3) as such a resource. We constructed an average template brain at 10 μm voxel resolution by interpolating high resolution in-plane serial two-photon tomography images with 100 μm z-sampling from 1,675 young adult C57BL/6J mice. Then, using multimodal reference data, we parcellated the entire brain directly in 3D, labeling every voxel with a brain structure spanning 43 isocortical areas and their layers, 329 subcortical gray matter structures, 81 fiber tracts, and 8 ventricular structures. CCFv3 can be used to analyze, visualize, and integrate multimodal and multiscale datasets in 3D and is openly accessible (https://atlas.brain-map.org/).
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Affiliation(s)
- Quanxin Wang
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | - Song-Lin Ding
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | - Yang Li
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | - Josh Royall
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | - David Feng
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | - Phil Lesnar
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | - Nile Graddis
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | - Maitham Naeemi
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | - Benjamin Facer
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | - Anh Ho
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | - Tim Dolbeare
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | | | - Nick Dee
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | - Wayne Wakeman
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | | | - Aaron Szafer
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | - Susan M Sunkin
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | - Seung Wook Oh
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | - Amy Bernard
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | | | | | - Christof Koch
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | - Hongkui Zeng
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | - Julie A Harris
- Allen Institute for Brain Science, Seattle, WA 98109, USA.
| | - Lydia Ng
- Allen Institute for Brain Science, Seattle, WA 98109, USA.
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15
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Layer 6b Is Driven by Intracortical Long-Range Projection Neurons. Cell Rep 2020; 30:3492-3505.e5. [DOI: 10.1016/j.celrep.2020.02.044] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 09/20/2019] [Accepted: 02/10/2020] [Indexed: 01/03/2023] Open
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16
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Lavin TK, Jin L, Lea NE, Wickersham IR. Monosynaptic Tracing Success Depends Critically on Helper Virus Concentrations. Front Synaptic Neurosci 2020; 12:6. [PMID: 32116642 PMCID: PMC7033752 DOI: 10.3389/fnsyn.2020.00006] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Accepted: 01/23/2020] [Indexed: 11/13/2022] Open
Abstract
Monosynaptically-restricted transsynaptic tracing using deletion-mutant rabies virus (RV) has become a widely used technique in neuroscience, allowing identification, imaging, and manipulation of neurons directly presynaptic to a starting neuronal population. Its most common implementation is to use Cre mouse lines in combination with Cre-dependent "helper" adeno-associated viral vectors (AAVs) to supply the required genes to the targeted population before subsequent injection of a first-generation (ΔG) rabies viral vector. Here we show that the efficiency of transsynaptic spread and the degree of nonspecific labeling in wild-type control animals depend strongly on the concentrations of these helper AAVs. Our results suggest practical guidelines for achieving good results.
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Affiliation(s)
| | | | | | - Ian R. Wickersham
- McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA, United States
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17
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Blankvoort S, Descamps LAL, Kentros C. Enhancer-Driven Gene Expression (EDGE) enables the generation of cell type specific tools for the analysis of neural circuits. Neurosci Res 2020; 152:78-86. [PMID: 31958494 DOI: 10.1016/j.neures.2020.01.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 01/10/2020] [Accepted: 01/10/2020] [Indexed: 12/20/2022]
Abstract
As in all circuits, fully understanding how neural circuits operate requires the ability to specifically manipulate individual circuit elements, i.e. particular neuronal cell types. While recent years saw the development of molecular genetic tools allowing one to control and monitor neuronal activity, progress is limited by the ability to express such transgenes specifically enough. This goal is complicated by the fact that we are only beginning to understand how many cell types exist in the mammalian brain. Obtaining neuronal cell type-specific expression requires co-opting the genetic machinery which specifies their striking diversity, typically done by making transgenic animals using promoters expressing in neurons. However, while the vast majority of genes express in the brain, they almost always express in multiple cell types, meaning native promoters are not specific enough. We have recently taken a new approach to increase the specificity of transgene expression based upon identifying the distal cis-regulatory genomic elements (i.e. enhancers) uniquely active in a brain region and combining them with a heterologous minimal promoter. Termed Enhancer-Driven Gene Expression (EDGE), it allows for the generation of transgenic animals targeting the cell types of any brain region with far greater specificity than can be obtained with native promoters. Moreover, their small size allows for the generation of cell-specific viral vectors, conceivably enabling circuit-specific manipulations to any species.
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Affiliation(s)
- Stefan Blankvoort
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, NTNU, Trondheim, Norway.
| | - Lucie A L Descamps
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, NTNU, Trondheim, Norway
| | - Cliff Kentros
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, NTNU, Trondheim, Norway.
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18
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Clark EA, Shima Y, Nelson S. ATAC-seq on Sorted Adult Mouse Neurons. Bio Protoc 2019; 9:e3382. [PMID: 33654878 DOI: 10.21769/bioprotoc.3382] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 08/26/2019] [Accepted: 09/08/2019] [Indexed: 11/02/2022] Open
Abstract
Transcription regulation is a key aspect of cellular identity established during development and maintained into adulthood. Molecular and biochemical assays that probe the genome are critical tools in exploring mechanisms of transcription regulation and cell type identity. The mammalian brain is composed of a huge diversity of cell types with distinct properties and functions. To understand these specific roles, it is necessary to selectively target cell populations for study. However, the need to selectively study restricted cell populations poses a challenge in neurobiology. It is often difficult to collect sufficient cellular input for many standard biochemical and molecular assays. Recently, important advances have been made to scale assays down, opening up new frontiers to explore molecular mechanisms in neurons. Concurrently, methodologies for preparing neurons for such assays has advanced taking into consideration specific methods to preserve the cell biology meant to be assayed. Here we describe a method for preparing live neurons from adult brain tissue for the Assay for Transposase Accessible Chromatin (ATAC).
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Affiliation(s)
- Erin A Clark
- Department of Biology and Program in Neuroscience, Brandeis University, Waltham, USA
| | - Yasuyuki Shima
- Department of Biology and Program in Neuroscience, Brandeis University, Waltham, USA
| | - Sacha Nelson
- Department of Biology and Program in Neuroscience, Brandeis University, Waltham, USA
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19
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Winnubst J, Bas E, Ferreira TA, Wu Z, Economo MN, Edson P, Arthur BJ, Bruns C, Rokicki K, Schauder D, Olbris DJ, Murphy SD, Ackerman DG, Arshadi C, Baldwin P, Blake R, Elsayed A, Hasan M, Ramirez D, Dos Santos B, Weldon M, Zafar A, Dudman JT, Gerfen CR, Hantman AW, Korff W, Sternson SM, Spruston N, Svoboda K, Chandrashekar J. Reconstruction of 1,000 Projection Neurons Reveals New Cell Types and Organization of Long-Range Connectivity in the Mouse Brain. Cell 2019; 179:268-281.e13. [PMID: 31495573 DOI: 10.1016/j.cell.2019.07.042] [Citation(s) in RCA: 254] [Impact Index Per Article: 50.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 05/14/2019] [Accepted: 07/23/2019] [Indexed: 01/15/2023]
Abstract
Neuronal cell types are the nodes of neural circuits that determine the flow of information within the brain. Neuronal morphology, especially the shape of the axonal arbor, provides an essential descriptor of cell type and reveals how individual neurons route their output across the brain. Despite the importance of morphology, few projection neurons in the mouse brain have been reconstructed in their entirety. Here we present a robust and efficient platform for imaging and reconstructing complete neuronal morphologies, including axonal arbors that span substantial portions of the brain. We used this platform to reconstruct more than 1,000 projection neurons in the motor cortex, thalamus, subiculum, and hypothalamus. Together, the reconstructed neurons constitute more than 85 meters of axonal length and are available in a searchable online database. Axonal shapes revealed previously unknown subtypes of projection neurons and suggest organizational principles of long-range connectivity.
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Affiliation(s)
- Johan Winnubst
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Erhan Bas
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Tiago A Ferreira
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Zhuhao Wu
- Laboratory of Molecular Genetics, The Rockefeller University, New York, NY 10065, USA
| | - Michael N Economo
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | | | - Ben J Arthur
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Christopher Bruns
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Konrad Rokicki
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - David Schauder
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Donald J Olbris
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Sean D Murphy
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - David G Ackerman
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Cameron Arshadi
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Perry Baldwin
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Regina Blake
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Ahmad Elsayed
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Mashtura Hasan
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Daniel Ramirez
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Bruno Dos Santos
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Monet Weldon
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Amina Zafar
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Joshua T Dudman
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Charles R Gerfen
- Intramural Research Program, National Institute of Mental Health, Bethesda, MD 20892, USA
| | - Adam W Hantman
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Wyatt Korff
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Scott M Sternson
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Nelson Spruston
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Karel Svoboda
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
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20
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Chevée M, Robertson JDJ, Cannon GH, Brown SP, Goff LA. Variation in Activity State, Axonal Projection, and Position Define the Transcriptional Identity of Individual Neocortical Projection Neurons. Cell Rep 2019; 22:441-455. [PMID: 29320739 DOI: 10.1016/j.celrep.2017.12.046] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Revised: 11/17/2017] [Accepted: 12/12/2017] [Indexed: 12/31/2022] Open
Abstract
Single-cell RNA sequencing has generated catalogs of transcriptionally defined neuronal subtypes of the brain. However, the cellular processes that contribute to neuronal subtype specification and transcriptional heterogeneity remain unclear. By comparing the gene expression profiles of single layer 6 corticothalamic neurons in somatosensory cortex, we show that transcriptional subtypes primarily reflect axonal projection pattern, laminar position within the cortex, and neuronal activity state. Pseudotemporal ordering of 1,023 cellular responses to sensory manipulation demonstrates that changes in expression of activity-induced genes both reinforced cell-type identity and contributed to increased transcriptional heterogeneity within each cell type. This is due to cell-type biased choices of transcriptional states following manipulation of neuronal activity. These results reveal that axonal projection pattern, laminar position, and activity state define significant axes of variation that contribute both to the transcriptional identity of individual neurons and to the transcriptional heterogeneity within each neuronal subtype.
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Affiliation(s)
- Maxime Chevée
- Biochemistry, Cellular and Molecular Biology Graduate Program, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Johanna De Jong Robertson
- Human Genetics Training Program, McKusick-Nathans Institute for Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Gabrielle Heather Cannon
- McKusick-Nathans Institute for Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Solange Pezon Brown
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
| | - Loyal Andrew Goff
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; McKusick-Nathans Institute for Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
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21
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Luo L, Callaway EM, Svoboda K. Genetic Dissection of Neural Circuits: A Decade of Progress. Neuron 2019; 98:256-281. [PMID: 29673479 DOI: 10.1016/j.neuron.2018.03.040] [Citation(s) in RCA: 228] [Impact Index Per Article: 45.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Revised: 03/16/2018] [Accepted: 03/21/2018] [Indexed: 01/24/2023]
Abstract
Tremendous progress has been made since Neuron published our Primer on genetic dissection of neural circuits 10 years ago. Since then, cell-type-specific anatomical, neurophysiological, and perturbation studies have been carried out in a multitude of invertebrate and vertebrate organisms, linking neurons and circuits to behavioral functions. New methods allow systematic classification of cell types and provide genetic access to diverse neuronal types for studies of connectivity and neural coding during behavior. Here we evaluate key advances over the past decade and discuss future directions.
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Affiliation(s)
- Liqun Luo
- Department of Biology, Howard Hughes Medical Institute, Stanford University, Stanford, CA 94305, USA
| | - Edward M Callaway
- Systems Neurobiology Laboratory, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA.
| | - Karel Svoboda
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, VA 20147, USA
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22
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Cuoco JA, Esposito AW, Moriarty S, Tang Y, Seth S, Toia AR, Kampton EB, Mayr Y, Khan M, Khan MB, Mullen BR, Ackman JB, Siddiqi F, Wolfe JH, Savinova OV, Ramos RL. Malformation of the Posterior Cerebellar Vermis Is a Common Neuroanatomical Phenotype of Genetically Engineered Mice on the C57BL/6 Background. THE CEREBELLUM 2019; 17:173-190. [PMID: 29043563 DOI: 10.1007/s12311-017-0892-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
C57BL/6 mice exhibit spontaneous cerebellar malformations consisting of heterotopic neurons and glia in the molecular layer of the posterior vermis, indicative of neuronal migration defect during cerebellar development. Recognizing that many genetically engineered (GE) mouse lines are produced from C57BL/6 ES cells or backcrossed to this strain, we performed histological analyses and found that cerebellar heterotopia were a common feature present in the majority of GE lines on this background. Furthermore, we identify GE mouse lines that will be valuable in the study of cerebellar malformations including diverse driver, reporter, and optogenetic lines. Finally, we discuss the implications that these data have on the use of C57BL/6 mice and GE mice on this background in studies of cerebellar development or as models of disease.
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Affiliation(s)
- Joshua A Cuoco
- Department of Biomedical Sciences, College of Osteopathic Medicine, New York Institute of Technology, Northern Boulevard, PO Box 8000, Old Westbury, NY, 11568-8000, USA
| | - Anthony W Esposito
- Department of Biomedical Sciences, College of Osteopathic Medicine, New York Institute of Technology, Northern Boulevard, PO Box 8000, Old Westbury, NY, 11568-8000, USA
| | - Shannon Moriarty
- Department of Biomedical Sciences, College of Osteopathic Medicine, New York Institute of Technology, Northern Boulevard, PO Box 8000, Old Westbury, NY, 11568-8000, USA
| | - Ying Tang
- Department of Biomedical Sciences, College of Osteopathic Medicine, New York Institute of Technology, Northern Boulevard, PO Box 8000, Old Westbury, NY, 11568-8000, USA
| | - Sonika Seth
- Department of Biomedical Sciences, College of Osteopathic Medicine, New York Institute of Technology, Northern Boulevard, PO Box 8000, Old Westbury, NY, 11568-8000, USA
| | - Alyssa R Toia
- Department of Biomedical Sciences, College of Osteopathic Medicine, New York Institute of Technology, Northern Boulevard, PO Box 8000, Old Westbury, NY, 11568-8000, USA
| | - Elias B Kampton
- Department of Biomedical Sciences, College of Osteopathic Medicine, New York Institute of Technology, Northern Boulevard, PO Box 8000, Old Westbury, NY, 11568-8000, USA
| | - Yevgeniy Mayr
- Department of Biomedical Sciences, College of Osteopathic Medicine, New York Institute of Technology, Northern Boulevard, PO Box 8000, Old Westbury, NY, 11568-8000, USA
| | - Mussarah Khan
- Department of Biomedical Sciences, College of Osteopathic Medicine, New York Institute of Technology, Northern Boulevard, PO Box 8000, Old Westbury, NY, 11568-8000, USA
| | - Mohammad B Khan
- Department of Biomedical Sciences, College of Osteopathic Medicine, New York Institute of Technology, Northern Boulevard, PO Box 8000, Old Westbury, NY, 11568-8000, USA
| | - Brian R Mullen
- Department of Molecular, Cell and Developmental Biology, University of California Santa Cruz, Santa Cruz, CA, 95064, USA
| | - James B Ackman
- Department of Molecular, Cell and Developmental Biology, University of California Santa Cruz, Santa Cruz, CA, 95064, USA
| | - Faez Siddiqi
- Division of Neurology and Research Institute of Children's Hospital of Philadelphia, Philadelphia, PA, 19104, USA
| | - John H Wolfe
- Division of Neurology and Research Institute of Children's Hospital of Philadelphia, Philadelphia, PA, 19104, USA
- Department of Pediatrics, Perelman School of Medicine and W.F. Goodman Center for Comparative Medical Genetics, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Olga V Savinova
- Department of Biomedical Sciences, College of Osteopathic Medicine, New York Institute of Technology, Northern Boulevard, PO Box 8000, Old Westbury, NY, 11568-8000, USA
| | - Raddy L Ramos
- Department of Biomedical Sciences, College of Osteopathic Medicine, New York Institute of Technology, Northern Boulevard, PO Box 8000, Old Westbury, NY, 11568-8000, USA.
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23
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Balmer TS, Trussell LO. Selective targeting of unipolar brush cell subtypes by cerebellar mossy fibers. eLife 2019; 8:44964. [PMID: 30994458 PMCID: PMC6469928 DOI: 10.7554/elife.44964] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Accepted: 03/12/2019] [Indexed: 01/26/2023] Open
Abstract
In vestibular cerebellum, primary afferents carry signals from single vestibular end organs, whereas secondary afferents from vestibular nucleus carry integrated signals. Selective targeting of distinct mossy fibers determines how the cerebellum processes vestibular signals. We focused on vestibular projections to ON and OFF classes of unipolar brush cells (UBCs), which transform single mossy fiber signals into long-lasting excitation or inhibition respectively, and impact the activity of ensembles of granule cells. To determine whether these contacts are indeed selective, connectivity was traced back from UBC to specific ganglion cell, hair cell and vestibular organ subtypes in mice. We show that a specialized subset of primary afferents contacts ON UBCs, but not OFF UBCs, while secondary afferents contact both subtypes. Striking anatomical differences were observed between primary and secondary afferents, their synapses, and the UBCs they contact. Thus, each class of UBC functions to transform specific signals through distinct anatomical pathways. While out jogging, you have no trouble keeping your eyes fixed on objects in the distance even though your head and eyes are moving with every step. Humans owe this stability of the visual world partly to a region of the brain called the vestibular cerebellum. From its position underneath the rest of the brain, the vestibular cerebellum detects head motion and then triggers compensatory movements to stabilize the head, body and eyes. The vestibular cerebellum receives sensory input from the body via direct and indirect routes. The direct input comes from five structures within the inner ear, each of which detects movement of the head in one particular direction. The indirect input travels to the cerebellum via the brainstem, which connects the brain with the spinal cord. The indirect input contains information on head movements in multiple directions combined with input from other senses such as vision. By studying the mouse brain, Balmer and Trussell have now mapped the direct and indirect circuits that carry sensory information to the vestibular cerebellum. Both types of input activate cells within the vestibular cerebellum called unipolar brush cells (UBCs). There are two types of UBCs: ON and OFF. Direct sensory input from the inner ear activates only ON UBCs. These cells respond to the arrival of sensory input by increasing their activity. Indirect input from the brainstem activates both ON UBCs and OFF UBCs. The latter respond to the input by decreasing their activity. The vestibular cerebellum thus processes direct and indirect inputs via segregated pathways containing different types of UBCs. The next step in understanding how the cerebellum maintains a stable visual world is to identify the circuitry beyond the UBCs. Understanding these circuits will ultimately provide insights into balance disorders, such as vertigo.
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Affiliation(s)
- Timothy S Balmer
- Vollum Institute and Oregon Hearing Research Center, Oregon Health and Science University, Portland, United States
| | - Laurence O Trussell
- Vollum Institute and Oregon Hearing Research Center, Oregon Health and Science University, Portland, United States
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24
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Sugino K, Clark E, Schulmann A, Shima Y, Wang L, Hunt DL, Hooks BM, Tränkner D, Chandrashekar J, Picard S, Lemire AL, Spruston N, Hantman AW, Nelson SB. Mapping the transcriptional diversity of genetically and anatomically defined cell populations in the mouse brain. eLife 2019; 8:38619. [PMID: 30977723 PMCID: PMC6499542 DOI: 10.7554/elife.38619] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Accepted: 04/11/2019] [Indexed: 01/27/2023] Open
Abstract
Understanding the principles governing neuronal diversity is a fundamental goal for neuroscience. Here, we provide an anatomical and transcriptomic database of nearly 200 genetically identified cell populations. By separately analyzing the robustness and pattern of expression differences across these cell populations, we identify two gene classes contributing distinctly to neuronal diversity. Short homeobox transcription factors distinguish neuronal populations combinatorially, and exhibit extremely low transcriptional noise, enabling highly robust expression differences. Long neuronal effector genes, such as channels and cell adhesion molecules, contribute disproportionately to neuronal diversity, based on their patterns rather than robustness of expression differences. By linking transcriptional identity to genetic strains and anatomical atlases, we provide an extensive resource for further investigation of mouse neuronal cell types.
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Affiliation(s)
- Ken Sugino
- Janelia Research CampusAshburnUnited States
| | | | | | | | - Lihua Wang
- Janelia Research CampusAshburnUnited States
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25
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Enhancer Trapping and Annotation in Zebrafish Mediated with Sleeping Beauty, piggyBac and Tol2 Transposons. Genes (Basel) 2018; 9:genes9120630. [PMID: 30551672 PMCID: PMC6316676 DOI: 10.3390/genes9120630] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 12/07/2018] [Accepted: 12/10/2018] [Indexed: 12/18/2022] Open
Abstract
Although transposon-mediated enhancer trapping (ET) is successfully applied in diverse models, the efficiency of various transposon systems varies significantly, and little information is available regarding efficiency of enhancer trapping by various transposons in zebrafish. Most potential enhancers (Ens) still lack evidence of actual En activity. Here, we compared the differences in ET efficiency between sleeping beauty (SB), piggyBac (PB) and Tol2 transposons. Tol2 represented the highest germline transfer efficiencies at 55.56% (NF0 = 165), followed by SB (38.36%, NF0 = 151) and PB (32.65%, NF0 = 149). ET lines generated by the Tol2 transposon tended to produce offspring with a single expression pattern per line, while PB and SB tended to generate embryos with multiple expression patterns. In our tests, 10 putative Ens (En1–10) were identified by splinkerette PCR and comparative genomic analysis. Combining the GFP expression profiles and mRNA expression patterns revealed that En1 and En2 may be involved in regulation of the expression of dlx1a and dlx2a, while En6 may be involved in regulation of the expression of line TK4 transgene and rps26, and En7 may be involved in the regulation of the expression of wnt1 and wnt10b. Most identified Ens were found to be transcribed in zebrafish embryos, and their regulatory function may involve eRNAs.
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26
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Developmental pattern and structural factors of dendritic survival in cerebellar granule cells in vivo. Sci Rep 2018; 8:17561. [PMID: 30510282 PMCID: PMC6277421 DOI: 10.1038/s41598-018-35829-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 11/12/2018] [Indexed: 12/17/2022] Open
Abstract
Granule cells (GCs) in the cerebellar cortex are important for sparse encoding of afferent sensorimotor information. Modeling studies show that GCs can perform their function most effectively when they have four dendrites. Indeed, mature GCs have four short dendrites on average, each terminating in a claw-like ending that receives both excitatory and inhibitory inputs. Immature GCs, however, have significantly more dendrites—all without claws. How these redundant dendrites are refined during development is largely unclear. Here, we used in vivo time-lapse imaging and immunohistochemistry to study developmental refinement of GC dendritic arbors and its relation to synapse formation. We found that while the formation of dendritic claws stabilized the dendrites, the selection of surviving dendrites was made before claw formation, and longer immature dendrites had a significantly higher chance of survival than shorter dendrites. Using immunohistochemistry, we show that glutamatergic and GABAergic synapses are transiently formed on immature GC dendrites, and the number of GABAergic, but not glutamatergic, synapses correlates with the length of immature dendrites. Together, these results suggest a potential role of transient GABAergic synapses on dendritic selection and show that preselected dendrites are stabilized by the formation of dendritic claws—the site of mature synapses.
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Laboulaye MA, Duan X, Qiao M, Whitney IE, Sanes JR. Mapping Transgene Insertion Sites Reveals Complex Interactions Between Mouse Transgenes and Neighboring Endogenous Genes. Front Mol Neurosci 2018; 11:385. [PMID: 30405348 PMCID: PMC6206269 DOI: 10.3389/fnmol.2018.00385] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Accepted: 09/25/2018] [Indexed: 11/13/2022] Open
Abstract
Transgenic mouse lines are routinely employed to label and manipulate distinct cell types. The transgene generally comprises cell-type specific regulatory elements linked to a cDNA encoding a reporter or other protein. However, off-target expression seemingly unrelated to the regulatory elements in the transgene is often observed, it is sometimes suspected to reflect influences related to the site of transgene integration in the genome. To test this hypothesis, we used a proximity ligation-based method, Targeted Locus Amplification (TLA), to map the insertion sites of three well-characterized transgenes that appeared to exhibit insertion site-dependent expression in retina. The nearest endogenous genes to transgenes HB9-GFP, Mito-P, and TYW3 are Cdh6, Fat4 and Khdrbs2, respectively. For two lines, we demonstrate that expression reflects that of the closest endogenous gene (Fat4 and Cdh6), even though the distance between transgene and endogenous gene is 550 and 680 kb, respectively. In all three lines, the transgenes decrease expression of the neighboring endogenous genes. In each case, the affected endogenous gene was expressed in at least some of the cell types that the transgenic line has been used to mark and study. These results provide insights into the effects of transgenes and endogenous genes on each other's expression, demonstrate that mapping insertion site is valuable for interpreting results obtained with transgenic lines, and indicate that TLA is a reliable method for integration site discovery.
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Affiliation(s)
| | | | | | | | - Joshua R. Sanes
- Center for Brain Science and Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA, United States
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28
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Bedbrook CN, Deverman BE, Gradinaru V. Viral Strategies for Targeting the Central and Peripheral Nervous Systems. Annu Rev Neurosci 2018; 41:323-348. [DOI: 10.1146/annurev-neuro-080317-062048] [Citation(s) in RCA: 94] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Recombinant viruses allow for targeted transgene expression in specific cell populations throughout the nervous system. The adeno-associated virus (AAV) is among the most commonly used viruses for neuroscience research. Recombinant AAVs (rAAVs) are highly versatile and can package most cargo composed of desired genes within the capsid's ∼5-kb carrying capacity. Numerous regulatory elements and intersectional strategies have been validated in rAAVs to enable cell type–specific expression. rAAVs can be delivered to specific neuronal populations or globally throughout the animal. The AAV capsids have natural cell type or tissue tropism and trafficking that can be modified for increased specificity. Here, we describe recently engineered AAV capsids and associated cargo that have extended the utility of AAVs in targeting molecularly defined neurons throughout the nervous system, which will further facilitate neuronal circuit interrogation and discovery.
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Affiliation(s)
- Claire N. Bedbrook
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California 91125, USA
| | - Benjamin E. Deverman
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California 91125, USA
| | - Viviana Gradinaru
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California 91125, USA
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29
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Blankvoort S, Witter MP, Noonan J, Cotney J, Kentros C. Marked Diversity of Unique Cortical Enhancers Enables Neuron-Specific Tools by Enhancer-Driven Gene Expression. Curr Biol 2018; 28:2103-2114.e5. [PMID: 30008330 DOI: 10.1016/j.cub.2018.05.015] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Revised: 04/27/2018] [Accepted: 05/04/2018] [Indexed: 10/28/2022]
Abstract
Understanding neural circuit function requires individually addressing their component parts: specific neuronal cell types. However, not only do the precise genetic mechanisms specifying neuronal cell types remain obscure, access to these neuronal cell types by transgenic techniques also remains elusive. Whereas most genes are expressed in the brain, the vast majority are expressed in many different kinds of neurons, suggesting that promoters alone are not sufficiently specific to distinguish cell types. However, there are orders of magnitude more distal genetic cis-regulatory elements controlling transcription (i.e., enhancers), so we screened for enhancer activity in microdissected samples of mouse cortical subregions. This identified thousands of novel putative enhancers, many unique to particular cortical subregions. Pronuclear injection of expression constructs containing such region-specific enhancers resulted in transgenic lines driving expression in distinct sets of cells specifically in the targeted cortical subregions, even though the parent gene's promoter was relatively non-specific. These data showcase the promise of utilizing the genetic mechanisms underlying the specification of diverse neuronal cell types for the development of genetic tools potentially capable of targeting any neuronal circuit of interest, an approach we call enhancer-driven gene expression (EDGE).
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Affiliation(s)
- Stefan Blankvoort
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, NTNU, Trondheim, Norway
| | - Menno P Witter
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, NTNU, Trondheim, Norway
| | - James Noonan
- Department of Genetics, Yale School of Medicine, New Haven, CT, USA; Kavli Institute for Neuroscience, Yale University, New Haven, CT, USA
| | - Justin Cotney
- Department of Genetics, Yale School of Medicine, New Haven, CT, USA; Department of Genetics and Genome Sciences, University of Connecticut Health Centre, Farmington, CT, USA.
| | - Cliff Kentros
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, NTNU, Trondheim, Norway; Institute of Neuroscience, University of Oregon, Eugene, OR, USA.
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30
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He M, Huang ZJ. Genetic approaches to access cell types in mammalian nervous systems. Curr Opin Neurobiol 2018; 50:109-118. [PMID: 29471215 PMCID: PMC5984678 DOI: 10.1016/j.conb.2018.02.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Revised: 01/19/2018] [Accepted: 02/04/2018] [Indexed: 12/11/2022]
Abstract
Understanding brain circuit organization and function requires systematic dissection of its cellular components. With vast cell number and diversity, mammalian nervous systems present a daunting challenge for achieving specific and comprehensive cell type access-prerequisite to circuit analysis. Genetic approaches in the mouse have relied on germline engineering to access marker-defined cell populations. Combinatorial strategies that engage marker intersection, anatomy and projection pattern (e.g. antero-grade and retro-grade viral vectors), and developmental lineage substantially increase the specificity of cell type targeting. While increasing number of mouse cell types are becoming experimentally accessible, comprehensive coverage requires larger coordinated efforts with strategic infrastructural and fiscal planning. CRISPR-based genome editing may enable cell type access in other species, but issues of time, cost and ethics remain, especially for primates. Novel approaches that bypass the germline, such as somatic cell engineering and cell surface-based gene delivery, may reduce the barrier of genetic access to mammalian cell types.
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Affiliation(s)
- Miao He
- Department of Neurology, State Key Laboratory of Medical Neurobiology, Institutes of Brain Science, Zhongshan Hospital, Fudan University, Shanghai 200032, China.
| | - Z Josh Huang
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA.
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Specialized Subpopulations of Deep-Layer Pyramidal Neurons in the Neocortex: Bridging Cellular Properties to Functional Consequences. J Neurosci 2018; 38:5441-5455. [PMID: 29798890 DOI: 10.1523/jneurosci.0150-18.2018] [Citation(s) in RCA: 92] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 05/09/2018] [Accepted: 05/11/2018] [Indexed: 12/25/2022] Open
Abstract
Neocortical pyramidal neurons with somata in layers 5 and 6 are among the most visually striking and enigmatic neurons in the brain. These deep-layer pyramidal neurons (DLPNs) integrate a plethora of cortical and extracortical synaptic inputs along their impressive dendritic arbors. The pattern of cortical output to both local and long-distance targets is sculpted by the unique physiological properties of specific DLPN subpopulations. Here we revisit two broad DLPN subpopulations: those that send their axons within the telencephalon (intratelencephalic neurons) and those that project to additional target areas outside the telencephalon (extratelencephalic neurons). While neuroscientists across many subdisciplines have characterized the intrinsic and synaptic physiological properties of DLPN subpopulations, our increasing ability to selectively target and manipulate these output neuron subtypes advances our understanding of their distinct functional contributions. This Viewpoints article summarizes our current knowledge about DLPNs and highlights recent work elucidating the functional differences between DLPN subpopulations.
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Hoerder-Suabedissen A, Hayashi S, Upton L, Nolan Z, Casas-Torremocha D, Grant E, Viswanathan S, Kanold PO, Clasca F, Kim Y, Molnár Z. Subset of Cortical Layer 6b Neurons Selectively Innervates Higher Order Thalamic Nuclei in Mice. Cereb Cortex 2018; 28:1882-1897. [PMID: 29481606 PMCID: PMC6018949 DOI: 10.1093/cercor/bhy036] [Citation(s) in RCA: 78] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Revised: 01/25/2018] [Accepted: 01/28/2018] [Indexed: 12/16/2022] Open
Abstract
The thalamus receives input from 3 distinct cortical layers, but input from only 2 of these has been well characterized. We therefore investigated whether the third input, derived from layer 6b, is more similar to the projections from layer 6a or layer 5. We studied the projections of a restricted population of deep layer 6 cells ("layer 6b cells") taking advantage of the transgenic mouse Tg(Drd1a-cre)FK164Gsat/Mmucd (Drd1a-Cre), that selectively expresses Cre-recombinase in a subpopulation of layer 6b neurons across the entire cortical mantle. At P8, 18% of layer 6b neurons are labeled with Drd1a-Cre::tdTomato in somatosensory cortex (SS), and some co-express known layer 6b markers. Using Cre-dependent viral tracing, we identified topographical projections to higher order thalamic nuclei. VGluT1+ synapses formed by labeled layer 6b projections were found in posterior thalamic nucleus (Po) but not in the (pre)thalamic reticular nucleus (TRN). The lack of TRN collaterals was confirmed with single-cell tracing from SS. Transmission electron microscopy comparison of terminal varicosities from layer 5 and layer 6b axons in Po showed that L6b varicosities are markedly smaller and simpler than the majority from L5. Our results suggest that L6b projections to the thalamus are distinct from both L5 and L6a projections.
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Affiliation(s)
| | - Shuichi Hayashi
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3QX, UK
| | - Louise Upton
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3QX, UK
| | - Zachary Nolan
- Neural and Behavioral Sciences, Pennsylvania State University, 500 University Drive, Hershey, PA 17033, USA
| | - Diana Casas-Torremocha
- Department of Anatomy, Histology and Neuroscience, School of Medicine, Autónoma University, Madrid, Spain
| | - Eleanor Grant
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3QX, UK
| | - Sarada Viswanathan
- Department of Biology, University of Maryland, 1116 Biosciences Building,College Park, MD 20742, USA
| | - Patrick O Kanold
- Department of Biology, University of Maryland, 1116 Biosciences Building,College Park, MD 20742, USA
| | - Francisco Clasca
- Department of Anatomy, Histology and Neuroscience, School of Medicine, Autónoma University, Madrid, Spain
| | - Yongsoo Kim
- Neural and Behavioral Sciences, Pennsylvania State University, 500 University Drive, Hershey, PA 17033, USA
| | - Zoltán Molnár
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3QX, UK
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33
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Ecker JR, Geschwind DH, Kriegstein AR, Ngai J, Osten P, Polioudakis D, Regev A, Sestan N, Wickersham IR, Zeng H. The BRAIN Initiative Cell Census Consortium: Lessons Learned toward Generating a Comprehensive Brain Cell Atlas. Neuron 2017; 96:542-557. [PMID: 29096072 PMCID: PMC5689454 DOI: 10.1016/j.neuron.2017.10.007] [Citation(s) in RCA: 163] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Revised: 10/01/2017] [Accepted: 10/03/2017] [Indexed: 10/25/2022]
Abstract
A comprehensive characterization of neuronal cell types, their distributions, and patterns of connectivity is critical for understanding the properties of neural circuits and how they generate behaviors. Here we review the experiences of the BRAIN Initiative Cell Census Consortium, ten pilot projects funded by the U.S. BRAIN Initiative, in developing, validating, and scaling up emerging genomic and anatomical mapping technologies for creating a complete inventory of neuronal cell types and their connections in multiple species and during development. These projects lay the foundation for a larger and longer-term effort to generate whole-brain cell atlases in species including mice and humans.
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Affiliation(s)
- Joseph R Ecker
- Genomic Analysis Laboratory and Howard Hughes Medical Institute, Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | - Daniel H Geschwind
- Program in Neurogenetics, Departments of Neurology and Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Arnold R Kriegstein
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, Department of Neurology, University of California, San Francisco, San Francisco, CA 94143, USA
| | - John Ngai
- Department of Molecular and Cell Biology, Helen Wills Neuroscience Institute, QB3 Functional Genomics Laboratory, University of California, Berkeley, Berkeley, CA 94720, USA.
| | - Pavel Osten
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Damon Polioudakis
- Program in Neurogenetics, Departments of Neurology and Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Aviv Regev
- Klarman Cell Observatory, Broad Institute of MIT and Harvard, Department of Biology, Koch Institute of Integrative Cancer Research, and Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Nenad Sestan
- Departments of Neuroscience, Genetics, Psychiatry and Comparative Medicine, Program in Cellular Neuroscience, Neurodegeneration and Repair, Yale Child Study Center, Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | - Ian R Wickersham
- McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Hongkui Zeng
- Allen Institute for Brain Science, Seattle, WA 98109, USA
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34
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Kitamura T, Ogawa SK, Roy DS, Okuyama T, Morrissey MD, Smith LM, Redondo RL, Tonegawa S. Engrams and circuits crucial for systems consolidation of a memory. Science 2017; 356:73-78. [PMID: 28386011 PMCID: PMC5493329 DOI: 10.1126/science.aam6808] [Citation(s) in RCA: 553] [Impact Index Per Article: 79.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Accepted: 03/14/2017] [Indexed: 01/02/2023]
Abstract
Episodic memories initially require rapid synaptic plasticity within the hippocampus for their formation and are gradually consolidated in neocortical networks for permanent storage. However, the engrams and circuits that support neocortical memory consolidation have thus far been unknown. We found that neocortical prefrontal memory engram cells, which are critical for remote contextual fear memory, were rapidly generated during initial learning through inputs from both the hippocampal-entorhinal cortex network and the basolateral amygdala. After their generation, the prefrontal engram cells, with support from hippocampal memory engram cells, became functionally mature with time. Whereas hippocampal engram cells gradually became silent with time, engram cells in the basolateral amygdala, which were necessary for fear memory, were maintained. Our data provide new insights into the functional reorganization of engrams and circuits underlying systems consolidation of memory.
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Affiliation(s)
- Takashi Kitamura
- RIKEN-MIT Center for Neural Circuit Genetics at the Picower Institute for Learning and Memory, Departments of Biology and Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Sachie K Ogawa
- RIKEN-MIT Center for Neural Circuit Genetics at the Picower Institute for Learning and Memory, Departments of Biology and Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Dheeraj S Roy
- RIKEN-MIT Center for Neural Circuit Genetics at the Picower Institute for Learning and Memory, Departments of Biology and Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Teruhiro Okuyama
- RIKEN-MIT Center for Neural Circuit Genetics at the Picower Institute for Learning and Memory, Departments of Biology and Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Mark D Morrissey
- RIKEN-MIT Center for Neural Circuit Genetics at the Picower Institute for Learning and Memory, Departments of Biology and Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Lillian M Smith
- RIKEN-MIT Center for Neural Circuit Genetics at the Picower Institute for Learning and Memory, Departments of Biology and Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Roger L Redondo
- RIKEN-MIT Center for Neural Circuit Genetics at the Picower Institute for Learning and Memory, Departments of Biology and Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
- Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Susumu Tonegawa
- RIKEN-MIT Center for Neural Circuit Genetics at the Picower Institute for Learning and Memory, Departments of Biology and Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
- Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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35
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Gray LT, Yao Z, Nguyen TN, Kim TK, Zeng H, Tasic B. Layer-specific chromatin accessibility landscapes reveal regulatory networks in adult mouse visual cortex. eLife 2017; 6. [PMID: 28112643 PMCID: PMC5325622 DOI: 10.7554/elife.21883] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 01/22/2017] [Indexed: 12/20/2022] Open
Abstract
Mammalian cortex is a laminar structure, with each layer composed of a characteristic set of cell types with different morphological, electrophysiological, and connectional properties. Here, we define chromatin accessibility landscapes of major, layer-specific excitatory classes of neurons, and compare them to each other and to inhibitory cortical neurons using the Assay for Transposase-Accessible Chromatin with high-throughput sequencing (ATAC-seq). We identify a large number of layer-specific accessible sites, and significant association with genes that are expressed in specific cortical layers. Integration of these data with layer-specific transcriptomic profiles and transcription factor binding motifs enabled us to construct a regulatory network revealing potential key layer-specific regulators, including Cux1/2, Foxp2, Nfia, Pou3f2, and Rorb. This dataset is a valuable resource for identifying candidate layer-specific cis-regulatory elements in adult mouse cortex.
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Affiliation(s)
- Lucas T Gray
- Allen Institute for Brain Science, Seattle, United States
| | - Zizhen Yao
- Allen Institute for Brain Science, Seattle, United States
| | | | - Tae Kyung Kim
- Allen Institute for Brain Science, Seattle, United States
| | - Hongkui Zeng
- Allen Institute for Brain Science, Seattle, United States
| | - Bosiljka Tasic
- Allen Institute for Brain Science, Seattle, United States
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36
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Ipsilateral and Contralateral Retinal Ganglion Cells Express Distinct Genes during Decussation at the Optic Chiasm. eNeuro 2016; 3:eN-NWR-0169-16. [PMID: 27957530 PMCID: PMC5136615 DOI: 10.1523/eneuro.0169-16.2016] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2016] [Revised: 10/18/2016] [Accepted: 11/08/2016] [Indexed: 12/20/2022] Open
Abstract
The increasing availability of transcriptomic technologies within the last decade has facilitated high-throughput identification of gene expression differences that define distinct cell types as well as the molecular pathways that drive their specification. The retinal projection neurons, retinal ganglion cells (RGCs), can be categorized into distinct morphological and functional subtypes and by the laterality of their projections. Here, we present a method for purifying the sparse population of ipsilaterally projecting RGCs in mouse retina from their contralaterally projecting counterparts during embryonic development through rapid retrograde labeling followed by fluorescence-activated cell sorting. Through microarray analysis, we uncovered the distinct molecular signatures that define and distinguish ipsilateral and contralateral RGCs during the critical period of axonal outgrowth and decussation, with more than 300 genes differentially expressed within these two cell populations. Among the differentially expressed genes confirmed through in vivo expression validation, several genes that mark “immaturity” are expressed within postmitotic ipsilateral RGCs. Moreover, at least one complementary pair, Igf1 and Igfbp5, is upregulated in contralateral or ipsilateral RGCs, respectively, and may represent signaling pathways that determine ipsilateral versus contralateral RGC identity. Importantly, the cell cycle regulator cyclin D2 is highly expressed in peripheral ventral retina with a dynamic expression pattern that peaks during the period of ipsilateral RGC production. Thus, the molecular signatures of ipsilateral and contralateral RGCs and the mechanisms that regulate their differentiation are more diverse than previously expected.
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Striosome-dendron bouquets highlight a unique striatonigral circuit targeting dopamine-containing neurons. Proc Natl Acad Sci U S A 2016; 113:11318-11323. [PMID: 27647894 DOI: 10.1073/pnas.1613337113] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The dopamine systems of the brain powerfully influence movement and motivation. We demonstrate that striatonigral fibers originating in striosomes form highly unusual bouquet-like arborizations that target bundles of ventrally extending dopamine-containing dendrites and clusters of their parent nigral cell bodies. Retrograde tracing showed that these clustered cell bodies in turn project to the striatum as part of the classic nigrostriatal pathway. Thus, these striosome-dendron formations, here termed "striosome-dendron bouquets," likely represent subsystems with the nigro-striato-nigral loop that are affected in human disorders including Parkinson's disease. Within the bouquets, expansion microscopy resolved many individual striosomal fibers tightly intertwined with the dopamine-containing dendrites and also with afferents labeled by glutamatergic, GABAergic, and cholinergic markers and markers for astrocytic cells and fibers and connexin 43 puncta. We suggest that the striosome-dendron bouquets form specialized integrative units within the dopamine-containing nigral system. Given evidence that striosomes receive input from cortical regions related to the control of mood and motivation and that they link functionally to reinforcement and decision-making, the striosome-dendron bouquets could be critical to dopamine-related function in health and disease.
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38
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Steinmetz CC, Tatavarty V, Sugino K, Shima Y, Joseph A, Lin H, Rutlin M, Lambo M, Hempel CM, Okaty BW, Paradis S, Nelson SB, Turrigiano GG. Upregulation of μ3A Drives Homeostatic Plasticity by Rerouting AMPAR into the Recycling Endosomal Pathway. Cell Rep 2016; 16:2711-2722. [PMID: 27568566 DOI: 10.1016/j.celrep.2016.08.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2014] [Revised: 07/15/2016] [Accepted: 08/01/2016] [Indexed: 01/06/2023] Open
Abstract
Synaptic scaling is a form of homeostatic plasticity driven by transcription-dependent changes in AMPA-type glutamate receptor (AMPAR) trafficking. To uncover the pathways involved, we performed a cell-type-specific screen for transcripts persistently altered during scaling, which identified the μ subunit (μ3A) of the adaptor protein complex AP-3A. Synaptic scaling increased μ3A (but not other AP-3 subunits) in pyramidal neurons and redistributed dendritic μ3A and AMPAR to recycling endosomes (REs). Knockdown of μ3A prevented synaptic scaling and this redistribution, while overexpression (OE) of full-length μ3A or a truncated μ3A that cannot interact with the AP-3A complex was sufficient to drive AMPAR to REs. Finally, OE of μ3A acted synergistically with GRIP1 to recruit AMPAR to the dendritic membrane. These data suggest that excess μ3A acts independently of the AP-3A complex to reroute AMPAR to RE, generating a reservoir of receptors essential for the regulated recruitment to the synaptic membrane during scaling up.
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Affiliation(s)
- Celine C Steinmetz
- Department of Biology and Center for Behavioral Genomics, Brandeis University, Waltham, MA 02454, USA
| | - Vedakumar Tatavarty
- Department of Biology and Center for Behavioral Genomics, Brandeis University, Waltham, MA 02454, USA
| | - Ken Sugino
- Department of Biology and Center for Behavioral Genomics, Brandeis University, Waltham, MA 02454, USA
| | - Yasuyuki Shima
- Department of Biology and Center for Behavioral Genomics, Brandeis University, Waltham, MA 02454, USA
| | - Anne Joseph
- Department of Biology and Center for Behavioral Genomics, Brandeis University, Waltham, MA 02454, USA
| | - Heather Lin
- Department of Biology and Center for Behavioral Genomics, Brandeis University, Waltham, MA 02454, USA
| | - Michael Rutlin
- Department of Biology and Center for Behavioral Genomics, Brandeis University, Waltham, MA 02454, USA
| | - Mary Lambo
- Department of Brain and Cognitive Science, MIT, Cambridge, MA 02139, USA
| | - Chris M Hempel
- Department of Biology and Center for Behavioral Genomics, Brandeis University, Waltham, MA 02454, USA
| | - Benjamin W Okaty
- Department of Biology and Center for Behavioral Genomics, Brandeis University, Waltham, MA 02454, USA
| | - Suzanne Paradis
- Department of Biology and Center for Behavioral Genomics, Brandeis University, Waltham, MA 02454, USA
| | - Sacha B Nelson
- Department of Biology and Center for Behavioral Genomics, Brandeis University, Waltham, MA 02454, USA.
| | - Gina G Turrigiano
- Department of Biology and Center for Behavioral Genomics, Brandeis University, Waltham, MA 02454, USA.
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39
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Naka A, Adesnik H. Inhibitory Circuits in Cortical Layer 5. Front Neural Circuits 2016; 10:35. [PMID: 27199675 PMCID: PMC4859073 DOI: 10.3389/fncir.2016.00035] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Accepted: 04/18/2016] [Indexed: 01/19/2023] Open
Abstract
Inhibitory neurons play a fundamental role in cortical computation and behavior. Recent technological advances, such as two photon imaging, targeted in vivo recording, and molecular profiling, have improved our understanding of the function and diversity of cortical interneurons, but for technical reasons most work has been directed towards inhibitory neurons in the superficial cortical layers. Here we review current knowledge specifically on layer 5 (L5) inhibitory microcircuits, which play a critical role in controlling cortical output. We focus on recent work from the well-studied rodent barrel cortex, but also draw on evidence from studies in primary visual cortex and other cortical areas. The diversity of both deep inhibitory neurons and their pyramidal cell targets make this a challenging but essential area of study in cortical computation and sensory processing.
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Affiliation(s)
- Alexander Naka
- The Helen Wills Neuroscience Institute, University of California Berkeley Berkeley, CA, USA
| | - Hillel Adesnik
- The Helen Wills Neuroscience Institute, University of California BerkeleyBerkeley, CA, USA; Department of Molecular and Cell Biology, University of California BerkeleyBerkeley, CA, USA
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