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White CM, Rees CL, Wheeler DW, Hamilton DJ, Ascoli GA. Molecular expression profiles of morphologically defined hippocampal neuron types: Empirical evidence and relational inferences. Hippocampus 2019; 30:472-487. [PMID: 31596053 PMCID: PMC7875254 DOI: 10.1002/hipo.23165] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 08/14/2019] [Accepted: 08/22/2019] [Indexed: 12/12/2022]
Abstract
Gene and protein expressions are key determinants of cellular function. Neurons are the building blocks of brain circuits, yet the relationship between their molecular identity and the spatial distribution of their dendritic inputs and axonal outputs remains incompletely understood. The open-source knowledge base Hippocampome.org amasses such transcriptomic data from the scientific literature for morphologically defined neuron types in the rodent hippocampal formation: dentate gyrus, CA3, CA2, CA1, subiculum, and entorhinal cortex. Positive, negative, or mixed expression reports were initially obtained from published articles directly connecting molecular evidence to neurons with known axonal and dendritic patterns across hippocampal layers. Here, we supplement this information by collating, formalizing, and leveraging relational expression inferences that link a gene or protein expression or lack thereof to that of another molecule or to an anatomical location. With these additional interpretations, we freely release online a comprehensive human- and machine-readable molecular profile for more than 100 neuron types in Hippocampome.org. Analysis of these data ascertains the ability to distinguish unequivocally most neuron types in each of the major subdivisions of the hippocampus based on currently known biochemical markers. Moreover, grouping neuron types by expression similarity reveals eight superfamilies characterized by a few defining molecules.
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Affiliation(s)
- Charise M White
- Center for Neural Informatics, Structure, & Plasticity, Krasnow Institute for Advanced Study, George Mason University, Fairfax, Virginia
| | - Christopher L Rees
- Center for Neural Informatics, Structure, & Plasticity, Krasnow Institute for Advanced Study, George Mason University, Fairfax, Virginia
| | - Diek W Wheeler
- Center for Neural Informatics, Structure, & Plasticity, Krasnow Institute for Advanced Study, George Mason University, Fairfax, Virginia
| | - David J Hamilton
- Center for Neural Informatics, Structure, & Plasticity, Krasnow Institute for Advanced Study, George Mason University, Fairfax, Virginia
| | - Giorgio A Ascoli
- Center for Neural Informatics, Structure, & Plasticity, Krasnow Institute for Advanced Study, George Mason University, Fairfax, Virginia
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2
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Cervantes EP, Comin CH, Junior RMC, Costa LDF. Morphological Neuron Classification Based on Dendritic Tree Hierarchy. Neuroinformatics 2019; 17:147-161. [PMID: 30008070 DOI: 10.1007/s12021-018-9388-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
The shape of a neuron can reveal interesting properties about its function. Therefore, morphological neuron characterization can contribute to a better understanding of how the brain works. However, one of the great challenges of neuroanatomy is the definition of morphological properties that can be used for categorizing neurons. This paper proposes a new methodology for neuron morphological analysis by considering different hierarchies of the dendritic tree for characterizing and categorizing neuronal cells. The methodology consists in using different strategies for decomposing the dendritic tree along its hierarchies, allowing the identification of relevant parts (possibly related to specific neuronal functions) for classification tasks. A set of more than 5000 neurons corresponding to 10 classes were examined with supervised classification algorithms based on this strategy. It was found that classification accuracies similar to those obtained by using whole neurons can be achieved by considering only parts of the neurons. Branches close to the soma were found to be particularly relevant for classification.
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Affiliation(s)
| | - Cesar Henrique Comin
- Department of Computer Science, Federal University of São Carlos, São Carlos, Brazil
| | | | - Luciano da Fontoura Costa
- São Carlos Institute of Physics, University of São Paulo, PO Box 369, 13560-970, São Carlos, SP, Brazil
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3
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Gouwens NW, Sorensen SA, Berg J, Lee C, Jarsky T, Ting J, Sunkin SM, Feng D, Anastassiou CA, Barkan E, Bickley K, Blesie N, Braun T, Brouner K, Budzillo A, Caldejon S, Casper T, Castelli D, Chong P, Crichton K, Cuhaciyan C, Daigle TL, Dalley R, Dee N, Desta T, Ding SL, Dingman S, Doperalski A, Dotson N, Egdorf T, Fisher M, de Frates RA, Garren E, Garwood M, Gary A, Gaudreault N, Godfrey K, Gorham M, Gu H, Habel C, Hadley K, Harrington J, Harris JA, Henry A, Hill D, Josephsen S, Kebede S, Kim L, Kroll M, Lee B, Lemon T, Link KE, Liu X, Long B, Mann R, McGraw M, Mihalas S, Mukora A, Murphy GJ, Ng L, Ngo K, Nguyen TN, Nicovich PR, Oldre A, Park D, Parry S, Perkins J, Potekhina L, Reid D, Robertson M, Sandman D, Schroedter M, Slaughterbeck C, Soler-Llavina G, Sulc J, Szafer A, Tasic B, Taskin N, Teeter C, Thatra N, Tung H, Wakeman W, Williams G, Young R, Zhou Z, Farrell C, Peng H, Hawrylycz MJ, Lein E, Ng L, Arkhipov A, Bernard A, Phillips JW, Zeng H, Koch C. Classification of electrophysiological and morphological neuron types in the mouse visual cortex. Nat Neurosci 2019; 22:1182-1195. [PMID: 31209381 PMCID: PMC8078853 DOI: 10.1038/s41593-019-0417-0] [Citation(s) in RCA: 233] [Impact Index Per Article: 46.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Accepted: 04/25/2019] [Indexed: 12/21/2022]
Abstract
Understanding the diversity of cell types in the brain has been an enduring challenge and requires detailed characterization of individual neurons in multiple dimensions. To systematically profile morpho-electric properties of mammalian neurons, we established a single-cell characterization pipeline using standardized patch-clamp recordings in brain slices and biocytin-based neuronal reconstructions. We built a publicly accessible online database, the Allen Cell Types Database, to display these datasets. Intrinsic physiological properties were measured from 1,938 neurons from the adult laboratory mouse visual cortex, morphological properties were measured from 461 reconstructed neurons, and 452 neurons had both measurements available. Quantitative features were used to classify neurons into distinct types using unsupervised methods. We established a taxonomy of morphologically and electrophysiologically defined cell types for this region of the cortex, with 17 electrophysiological types, 38 morphological types and 46 morpho-electric types. There was good correspondence with previously defined transcriptomic cell types and subclasses using the same transgenic mouse lines.
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Affiliation(s)
| | | | - Jim Berg
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Changkyu Lee
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Tim Jarsky
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Jonathan Ting
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Susan M Sunkin
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - David Feng
- Allen Institute for Brain Science, Seattle, Washington, USA
| | | | - Eliza Barkan
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Kris Bickley
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Nicole Blesie
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Thomas Braun
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Krissy Brouner
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Agata Budzillo
- Allen Institute for Brain Science, Seattle, Washington, USA
| | | | - Tamara Casper
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Dan Castelli
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Peter Chong
- Allen Institute for Brain Science, Seattle, Washington, USA
| | | | | | - Tanya L Daigle
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Rachel Dalley
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Nick Dee
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Tsega Desta
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Song-Lin Ding
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Samuel Dingman
- Allen Institute for Brain Science, Seattle, Washington, USA
| | | | | | - Tom Egdorf
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Michael Fisher
- Allen Institute for Brain Science, Seattle, Washington, USA
| | | | - Emma Garren
- Allen Institute for Brain Science, Seattle, Washington, USA
| | | | - Amanda Gary
- Allen Institute for Brain Science, Seattle, Washington, USA
| | | | - Keith Godfrey
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Melissa Gorham
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Hong Gu
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Caroline Habel
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Kristen Hadley
- Allen Institute for Brain Science, Seattle, Washington, USA
| | | | - Julie A Harris
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Alex Henry
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - DiJon Hill
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Sam Josephsen
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Sara Kebede
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Lisa Kim
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Matthew Kroll
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Brian Lee
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Tracy Lemon
- Allen Institute for Brain Science, Seattle, Washington, USA
| | | | - Xiaoxiao Liu
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Brian Long
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Rusty Mann
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Medea McGraw
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Stefan Mihalas
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Alice Mukora
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Gabe J Murphy
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Lindsay Ng
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Kiet Ngo
- Allen Institute for Brain Science, Seattle, Washington, USA
| | | | | | - Aaron Oldre
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Daniel Park
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Sheana Parry
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Jed Perkins
- Allen Institute for Brain Science, Seattle, Washington, USA
| | | | - David Reid
- Allen Institute for Brain Science, Seattle, Washington, USA
| | | | - David Sandman
- Allen Institute for Brain Science, Seattle, Washington, USA
| | | | | | | | - Josef Sulc
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Aaron Szafer
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Bosiljka Tasic
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Naz Taskin
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Corinne Teeter
- Allen Institute for Brain Science, Seattle, Washington, USA
| | | | - Herman Tung
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Wayne Wakeman
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Grace Williams
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Rob Young
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Zhi Zhou
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Colin Farrell
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Hanchuan Peng
- Allen Institute for Brain Science, Seattle, Washington, USA
| | | | - Ed Lein
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Lydia Ng
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Anton Arkhipov
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - Amy Bernard
- Allen Institute for Brain Science, Seattle, Washington, USA
| | | | - Hongkui Zeng
- Allen Institute for Brain Science, Seattle, Washington, USA.
| | - Christof Koch
- Allen Institute for Brain Science, Seattle, Washington, USA
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4
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Bakken TE, Hodge RD, Miller JA, Yao Z, Nguyen TN, Aevermann B, Barkan E, Bertagnolli D, Casper T, Dee N, Garren E, Goldy J, Graybuck LT, Kroll M, Lasken RS, Lathia K, Parry S, Rimorin C, Scheuermann RH, Schork NJ, Shehata SI, Tieu M, Phillips JW, Bernard A, Smith KA, Zeng H, Lein ES, Tasic B. Single-nucleus and single-cell transcriptomes compared in matched cortical cell types. PLoS One 2018; 13:e0209648. [PMID: 30586455 PMCID: PMC6306246 DOI: 10.1371/journal.pone.0209648] [Citation(s) in RCA: 312] [Impact Index Per Article: 52.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Accepted: 12/10/2018] [Indexed: 12/21/2022] Open
Abstract
Transcriptomic profiling of complex tissues by single-nucleus RNA-sequencing (snRNA-seq) affords some advantages over single-cell RNA-sequencing (scRNA-seq). snRNA-seq provides less biased cellular coverage, does not appear to suffer cell isolation-based transcriptional artifacts, and can be applied to archived frozen specimens. We used well-matched snRNA-seq and scRNA-seq datasets from mouse visual cortex to compare cell type detection. Although more transcripts are detected in individual whole cells (~11,000 genes) than nuclei (~7,000 genes), we demonstrate that closely related neuronal cell types can be similarly discriminated with both methods if intronic sequences are included in snRNA-seq analysis. We estimate that the nuclear proportion of total cellular mRNA varies from 20% to over 50% for large and small pyramidal neurons, respectively. Together, these results illustrate the high information content of nuclear RNA for characterization of cellular diversity in brain tissues.
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Affiliation(s)
- Trygve E. Bakken
- Allen Institute for Brain Science, Seattle, WA, United States of America
| | - Rebecca D. Hodge
- Allen Institute for Brain Science, Seattle, WA, United States of America
| | - Jeremy A. Miller
- Allen Institute for Brain Science, Seattle, WA, United States of America
| | - Zizhen Yao
- Allen Institute for Brain Science, Seattle, WA, United States of America
| | - Thuc Nghi Nguyen
- Allen Institute for Brain Science, Seattle, WA, United States of America
| | - Brian Aevermann
- J. Craig Venter Institute, La Jolla, CA, United States of America
| | - Eliza Barkan
- Allen Institute for Brain Science, Seattle, WA, United States of America
| | - Darren Bertagnolli
- Allen Institute for Brain Science, Seattle, WA, United States of America
| | - Tamara Casper
- Allen Institute for Brain Science, Seattle, WA, United States of America
| | - Nick Dee
- Allen Institute for Brain Science, Seattle, WA, United States of America
| | - Emma Garren
- Allen Institute for Brain Science, Seattle, WA, United States of America
| | - Jeff Goldy
- Allen Institute for Brain Science, Seattle, WA, United States of America
| | - Lucas T. Graybuck
- Allen Institute for Brain Science, Seattle, WA, United States of America
| | - Matthew Kroll
- Allen Institute for Brain Science, Seattle, WA, United States of America
| | - Roger S. Lasken
- J. Craig Venter Institute, La Jolla, CA, United States of America
| | - Kanan Lathia
- Allen Institute for Brain Science, Seattle, WA, United States of America
| | - Sheana Parry
- Allen Institute for Brain Science, Seattle, WA, United States of America
| | - Christine Rimorin
- Allen Institute for Brain Science, Seattle, WA, United States of America
| | | | | | - Soraya I. Shehata
- Allen Institute for Brain Science, Seattle, WA, United States of America
| | - Michael Tieu
- Allen Institute for Brain Science, Seattle, WA, United States of America
| | - John W. Phillips
- Allen Institute for Brain Science, Seattle, WA, United States of America
| | - Amy Bernard
- Allen Institute for Brain Science, Seattle, WA, United States of America
| | - Kimberly A. Smith
- Allen Institute for Brain Science, Seattle, WA, United States of America
| | - Hongkui Zeng
- Allen Institute for Brain Science, Seattle, WA, United States of America
| | - Ed S. Lein
- Allen Institute for Brain Science, Seattle, WA, United States of America
| | - Bosiljka Tasic
- Allen Institute for Brain Science, Seattle, WA, United States of America
- * E-mail:
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5
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Comparing the Expression of Genes Related to Serotonin (5-HT) in C57BL/6J Mice and Humans Based on Data Available at the Allen Mouse Brain Atlas and Allen Human Brain Atlas. Neurol Res Int 2017. [PMID: 28630769 PMCID: PMC5463198 DOI: 10.1155/2017/7138926] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Brain atlases are tools based on comprehensive studies used to locate biological characteristics (structures, connections, proteins, and gene expression) in different regions of the brain. These atlases have been disseminated to the point where tools have been created to store, manage, and share the information they contain. This study used the data published by the Allen Mouse Brain Atlas (2004) for mice (C57BL/6J) and Allen Human Brain Atlas (2010) for humans (6 donors) to compare the expression of serotonin-related genes. Genes of interest were searched for manually in each case (in situ hybridization for mice and microarrays for humans), normalized expression data (z-scores) were extracted, and the results were graphed. Despite the differences in methodology, quantification, and subjects used in the process, a high degree of similarity was found between expression data. Here we compare expression in a way that allows the use of translational research methods to infer and validate knowledge. This type of study allows part of the relationship between structures and functions to be identified, by examining expression patterns and comparing levels of expression in different states, anatomical correlations, and phenotypes between different species. The study concludes by discussing the importance of knowing, managing, and disseminating comprehensive, open-access studies in neuroscience.
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6
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NPY+-, but not PV+- GABAergic neurons mediated long-range inhibition from infra- to prelimbic cortex. Transl Psychiatry 2016; 6:e736. [PMID: 26882036 PMCID: PMC4872436 DOI: 10.1038/tp.2016.7] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Revised: 12/22/2015] [Accepted: 01/14/2016] [Indexed: 01/10/2023] Open
Abstract
Anxiety disorders are thought to reflect deficits in the regulation of fear memories. While the amygdala has long been considered a site of storage of fear memories, newer findings suggest that the prefrontal cortex (PFC) is essential in the regulation of amygdala-dependent memories and fear expression. Here, activation of the prelimbic cortex (PrL) enhances the expression of fear, while an elevated activity in the infralimbic cortex (IL) enhances fear extinction. Despite the presence of these facts, we still know very little about the synaptic interconnectivity within the PFC. The aim of the present study was to investigate the inhibitory circuits between prelimbic and IL using morphological and electrophysiological methods. Our immunohistochemical analysis revealed that the distribution of PV(+)- and NPY(+)-GABAergic neurons was strikingly different within the PFC. In addition, we provided the first experimental evidence that the pyramidal neurons in the PrL received a direct inhibitory input mediated by bipolar NPY(+)-GABAergic projection neurons in the IL. Deletion of the anxiety-related neuroligin 2 gene caused a decrease of this direct synaptic inhibition that originated from the IL. Thus, our data suggested that activation of the IL might not only directly activate the corresponding downstream anxiolytic pathway, but also suppress the PrL-related anxiogenic pathway and thus could differentially bias the regulation of fear expression and extinction.
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7
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Curtice KJ, Leavitt LS, Chase K, Raghuraman S, Horvath MP, Olivera BM, Teichert RW. Classifying neuronal subclasses of the cerebellum through constellation pharmacology. J Neurophysiol 2015; 115:1031-42. [PMID: 26581874 DOI: 10.1152/jn.00894.2015] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Accepted: 11/12/2015] [Indexed: 11/22/2022] Open
Abstract
A pressing need in neurobiology is the comprehensive identification and characterization of neuronal subclasses within the mammalian nervous system. To this end, we used constellation pharmacology as a method to interrogate the neuronal and glial subclasses of the mouse cerebellum individually and simultaneously. We then evaluated the data obtained from constellation-pharmacology experiments by cluster analysis to classify cells into neuronal and glial subclasses, based on their functional expression of glutamate, acetylcholine, and GABA receptors, among other ion channels. Conantokin peptides were used to identify N-methyl-d-aspartate (NMDA) receptor subtypes, which revealed that neurons of the young mouse cerebellum expressed NR2A and NR2B NMDA receptor subunits. Additional pharmacological tools disclosed differential expression of α-amino-3-hydroxy-5-methyl-4-isoxazloepropionic, nicotinic acetylcholine, and muscarinic acetylcholine receptors in different neuronal and glial subclasses. Certain cell subclasses correlated with known attributes of granule cells, and we combined constellation pharmacology with genetically labeled neurons to identify and characterize Purkinje cells. This study illustrates the utility of applying constellation pharmacology to classify neuronal and glial subclasses in specific anatomical regions of the brain.
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Affiliation(s)
- Kigen J Curtice
- Department of Biology, University of Utah, Salt Lake City, Utah
| | - Lee S Leavitt
- Department of Biology, University of Utah, Salt Lake City, Utah
| | - Kevin Chase
- Department of Biology, University of Utah, Salt Lake City, Utah
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8
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Teichert RW, Schmidt EW, Olivera BM. Constellation pharmacology: a new paradigm for drug discovery. Annu Rev Pharmacol Toxicol 2015; 55:573-89. [PMID: 25562646 DOI: 10.1146/annurev-pharmtox-010814-124551] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Constellation pharmacology is a cell-based high-content phenotypic-screening platform that utilizes subtype-selective pharmacological agents to elucidate the cell-specific combinations (constellations) of key signaling proteins that define specific cell types. Heterogeneous populations of native cells, in which the different individual cell types have been identified and characterized, are the foundation for this screening platform. Constellation pharmacology is useful for screening small molecules or for deconvoluting complex mixtures of biologically active natural products. This platform has been used to purify natural products and discover their molecular mechanisms. In the ongoing development of constellation pharmacology, there is a positive feedback loop between the pharmacological characterization of cell types and screening for new drug candidates. As constellation pharmacology is used to discover compounds with novel targeting-selectivity profiles, those new compounds then further help to elucidate the constellations of specific cell types, thereby increasing the content of this high-content platform.
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9
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Towards the automatic classification of neurons. Trends Neurosci 2015; 38:307-18. [PMID: 25765323 DOI: 10.1016/j.tins.2015.02.004] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Revised: 02/11/2015] [Accepted: 02/12/2015] [Indexed: 11/23/2022]
Abstract
The classification of neurons into types has been much debated since the inception of modern neuroscience. Recent experimental advances are accelerating the pace of data collection. The resulting growth of information about morphological, physiological, and molecular properties encourages efforts to automate neuronal classification by powerful machine learning techniques. We review state-of-the-art analysis approaches and the availability of suitable data and resources, highlighting prominent challenges and opportunities. The effective solution of the neuronal classification problem will require continuous development of computational methods, high-throughput data production, and systematic metadata organization to enable cross-laboratory integration.
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10
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Defining modulatory inputs into CNS neuronal subclasses by functional pharmacological profiling. Proc Natl Acad Sci U S A 2014; 111:6449-54. [PMID: 24733934 DOI: 10.1073/pnas.1404421111] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Previously we defined neuronal subclasses within the mouse peripheral nervous system using an experimental strategy called "constellation pharmacology." Here we demonstrate the broad applicability of constellation pharmacology by extending it to the CNS and specifically to the ventral respiratory column (VRC) of mouse brainstem, a region containing the neuronal network controlling respiratory rhythm. Analysis of dissociated cells from this locus revealed three major cell classes, each encompassing multiple subclasses. We broadly analyzed the combinations (constellations) of receptors and ion channels expressed within VRC cell classes and subclasses. These were strikingly different from the constellations of receptors and ion channels found in subclasses of peripheral neurons from mouse dorsal root ganglia. Within the VRC cell population, a subset of dissociated neurons responded to substance P, putatively corresponding to inspiratory pre-Bötzinger complex (preBötC) neurons. Using constellation pharmacology, we found that these substance P-responsive neurons also responded to histamine, and about half responded to bradykinin. Electrophysiological studies conducted in brainstem slices confirmed that preBötC neurons responsive to substance P exhibited similar responsiveness to bradykinin and histamine. The results demonstrate the predictive utility of constellation pharmacology for defining modulatory inputs into specific neuronal subclasses within central neuronal networks.
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11
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Using constellation pharmacology to define comprehensively a somatosensory neuronal subclass. Proc Natl Acad Sci U S A 2014; 111:2319-24. [PMID: 24469798 DOI: 10.1073/pnas.1324019111] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Change is intrinsic to nervous systems; change is required for learning and conditioning and occurs with disease progression, normal development, and aging. To better understand mammalian nervous systems and effectively treat nervous-system disorders, it is essential to track changes in relevant individual neurons. A critical challenge is to identify and characterize the specific cell types involved and the molecular-level changes that occur in each. Using an experimental strategy called constellation pharmacology, we demonstrate that we can define a specific somatosensory neuronal subclass, cold thermosensors, across different species and track changes in these neurons as a function of development. Cold thermosensors are uniformly responsive to menthol and innocuous cool temperature (17 °C), indicating that they express TRPM8 channels. A subset of cold thermosensors expressed α7 nicotinic acetylcholine receptors (nAChRs) but not other nAChR subtypes. Differences in temperature threshold of cold thermosensors correlated with functional expression of voltage-gated K channels Kv1.1/1.2: Relatively higher expression of KV1.1/1.2 channels resulted in a higher threshold response to cold temperature. Other signaling components varied during development and between species. In cold thermosensors of neonatal mice and rats, ATP receptors were functionally expressed, but the expression disappeared with development. This developmental change occurred earlier in low-threshold than high-threshold cold thermosensors. Most rat cold thermosensors expressed TRPA1 channels, whereas mouse cold thermosensors did not. The broad implications of this study are that it is now feasible to track changes in receptor and ion-channel expression in individual neuronal subclasses as a function of development, learning, disease, or aging.
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12
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Abstract
A complete understanding of nervous system function cannot be achieved without the identification of its component cell types. In this Perspective, we explore a series of related issues surrounding cell identity and how revolutionary methods for labeling and probing specific neuronal types have clarified this question. Specifically, we ask the following questions: what is the purpose of such diversity, how is it generated, how is it maintained, and, ultimately, how can one unambiguously identity one cell type from another? We suggest that each cell type can be defined by a unique and conserved molecular ground state that determines its capabilities. We believe that gaining an understanding of these molecular barcodes will advance our ability to explore brain function, enhance our understanding of the biochemical basis of CNS disorders, and aid in the development of novel therapeutic strategies.
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Affiliation(s)
- Gord Fishell
- Department of Neuroscience and Physiology, Neuroscience Institute, New York University, New York, NY 10016, USA.
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13
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van Aerde KI, Feldmeyer D. Morphological and physiological characterization of pyramidal neuron subtypes in rat medial prefrontal cortex. ACTA ACUST UNITED AC 2013; 25:788-805. [PMID: 24108807 DOI: 10.1093/cercor/bht278] [Citation(s) in RCA: 103] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
The medial prefrontal cortex (mPFC) has been implicated in cognitive and executive processes including decision making, working memory and behavioral flexibility. Cortical processing depends on the interaction between distinct neuronal cell types in different cortical layers. To better understand cortical processing in the rat mPFC, we studied the diversity of pyramidal neurons using in vitro whole-cell patch clamp recordings and biocytin staining of neurons, followed by morphological analysis. Using unsupervised cluster analysis for the objective grouping of neurons, we identified more than 10 different pyramidal subtypes spread across the different cortical layers. Layer 2 pyramidal neurons possessed a unique morphology with wide apical dendritic field spans and a narrow basal field span. Layer 3 contained the only subtype that showed a burst of action potentials upon current injection. Layer 5 pyramidal neurons showed the largest voltage sags. Finally, pyramidal neurons in layer 6 (L6) showed a great variety in their morphology with 39% of L6 neurons possessing tall apical dendrites that extend into layer 1. Future experiments on the functional role of the mPFC should take into account the great diversity of pyramidal neurons.
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Affiliation(s)
- Karlijn I van Aerde
- Forschungszentrum Jülich, Institute of Neuroscience and Medicine, INM-2, D-52425 Jülich, Germany Current address: Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Science, 1105 BA Amsterdam, The Netherlands
| | - Dirk Feldmeyer
- Forschungszentrum Jülich, Institute of Neuroscience and Medicine, INM-2, D-52425 Jülich, Germany Department of Psychiatry, Psychotherapy and Psychosomatics, RWTH Aachen University, Medical School, D-52074 Aachen, Germany Jülich Aachen Research Alliance, Translational Brain Medicine (JARA-Brain), D-52074 Aachen, Germany
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14
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Rebholz H, Zhou M, Nairn AC, Greengard P, Flajolet M. Selective knockout of the casein kinase 2 in d1 medium spiny neurons controls dopaminergic function. Biol Psychiatry 2013; 74:113-21. [PMID: 23290496 PMCID: PMC3878430 DOI: 10.1016/j.biopsych.2012.11.013] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2012] [Revised: 11/14/2012] [Accepted: 11/15/2012] [Indexed: 12/17/2022]
Abstract
BACKGROUND Dopamine, crucial for the regulation of motor function and reward, acts through receptors mainly expressed in striatum as well as cortex. Dysregulation of dopaminergic signaling is associated with various neuropsychiatric disorders. Consequently, dopamine-regulating drugs are effectively used in treating these disorders, such as L-DOPA for Parkinson's disease, methylphenidate for attention-deficit/hyperactivity disorder, or antipsychotics for schizophrenia. As a result, there has been much interest in dissecting signaling networks in the two morphologically indistinguishable D1- and D2-receptor-expressing medium spiny neurons. Our previous results highlighted a role for casein kinase 2 (CK2) in the modulation of dopamine D1 receptor (D1R) signaling in cells. METHODS To study the importance of CK2 in vivo, we have selectively knocked out CK2, in either D1- or D2-medium spiny neurons (MSNs) and characterized the mice behaviorally and biochemically (n = 4-18). RESULTS The D1-MSN knockout mice exhibited distinct behavioral phenotypes including novelty-induced hyperlocomotion and exploratory behavior, defective motor control, and motor learning. All of these behavioral traits are indicative of dysregulated dopamine signaling and the underlying mechanism appears to be an alteration of D1R signaling. In support of this hypothesis, D1R levels were upregulated in the knockout mice, as well as phosphorylation of DARPP-32 (dopamine- and cyclic adenosine monophosphate [cAMP]-regulated phospho-protein of 32 kDa), most of the behavioral phenotypes were abolished by the D1R antagonist, SCH23390, and the D2-MSN knockout mice displayed no obvious behavioral phenotype. CONCLUSIONS A single kinase, CK2, in D1-MSNs significantly alters dopamine signaling, a finding that could have therapeutic implications for disorders characterized by dopamine imbalance such as Parkinson's disease, attention-deficit/hyperactivity disorder, and schizophrenia.
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Affiliation(s)
- Heike Rebholz
- Laboratory of Molecular and Cellular Neuroscience, The Rockefeller University, New York, New York, 10065, USA
| | - Mingming Zhou
- Laboratory of Molecular and Cellular Neuroscience, The Rockefeller University, New York, New York, 10065, USA
| | - Angus C. Nairn
- Department of Psychiatry, Yale University School of Medicine, Ribicoff Research Facilities, CMHC, New Haven, CT 06508, US
| | - Paul Greengard
- Laboratory of Molecular and Cellular Neuroscience, The Rockefeller University, New York, New York, 10065, USA
| | - Marc Flajolet
- Laboratory of Molecular and Cellular Neuroscience, The Rockefeller University, New York, New York, 10065, USA
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15
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Ji S. Computational genetic neuroanatomy of the developing mouse brain: dimensionality reduction, visualization, and clustering. BMC Bioinformatics 2013; 14:222. [PMID: 23845024 PMCID: PMC3750329 DOI: 10.1186/1471-2105-14-222] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Accepted: 07/01/2013] [Indexed: 11/29/2022] Open
Abstract
Background The structured organization of cells in the brain plays a key role in its functional efficiency. This delicate organization is the consequence of unique molecular identity of each cell gradually established by precise spatiotemporal gene expression control during development. Currently, studies on the molecular-structural association are beginning to reveal how the spatiotemporal gene expression patterns are related to cellular differentiation and structural development. Results In this article, we aim at a global, data-driven study of the relationship between gene expressions and neuroanatomy in the developing mouse brain. To enable visual explorations of the high-dimensional data, we map the in situ hybridization gene expression data to a two-dimensional space by preserving both the global and the local structures. Our results show that the developing brain anatomy is largely preserved in the reduced gene expression space. To provide a quantitative analysis, we cluster the reduced data into groups and measure the consistency with neuroanatomy at multiple levels. Our results show that the clusters in the low-dimensional space are more consistent with neuroanatomy than those in the original space. Conclusions Gene expression patterns and developing brain anatomy are closely related. Dimensionality reduction and visual exploration facilitate the study of this relationship.
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Affiliation(s)
- Shuiwang Ji
- Department of Computer Science, Old Dominion University, 4700 Elkhorn Avenue, Suite 3300, Norfolk, VA 23529-0162, USA.
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16
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Vadakkan KI. A supplementary circuit rule-set for the neuronal wiring. Front Hum Neurosci 2013; 7:170. [PMID: 23641209 PMCID: PMC3640191 DOI: 10.3389/fnhum.2013.00170] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2012] [Accepted: 04/16/2013] [Indexed: 12/21/2022] Open
Abstract
Limitations of known anatomical circuit rules necessitate the identification of supplementary rules. This is essential for explaining how associative sensory stimuli induce nervous system changes that generate internal sensations of memory, concurrent with triggering specific motor activities in response to specific cue stimuli. A candidate mechanism is rapidly reversible, yet stabilizable membrane hemi-fusion formed between the closely apposed postsynaptic membranes of different neurons at locations of convergence of sensory inputs during associative learning. The lateral entry of activity from the cue stimulus-activated postsynapse re-activates the opposite postsynapse through the hemi-fused area and induces the basic units of internal sensation (namely, semblions) as a systems property. Working, short-term and long-term memories can be viewed as functions of the number of re-activatible hemi-fusions present at the time of memory retrieval. Blocking membrane hemi-fusion either by the insertion of the herpes simplex virus (HSV) glycoproteins or by the deposition of insoluble intermediates of amyloid protein in the inter-postsynaptic extracellular matrix (ECM) space leads to cognitive impairments, supporting this mechanism. The introduction of membrane fusion blockers into the postsynaptic cell cytoplasm that attenuates long-term potentiation (LTP), a correlate of behavioral motor activities in response to memory retrieval, provides further support. The lateral spread of activity through the inter-postsynaptic membrane is capable of contributing to oscillating neuronal activity at certain neuronal orders. At the resting state these oscillations provide sub-threshold activation to many neurons at higher orders, including motor neurons maintaining them at a low initiation threshold for motor activity.
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Affiliation(s)
- Kunjumon I Vadakkan
- Division of Neurology, Department of Internal Medicine, Faculty of Medicine, University of Manitoba Winnipeg, MB, Canada
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17
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Espinosa JS, Stryker MP. Development and plasticity of the primary visual cortex. Neuron 2012; 75:230-49. [PMID: 22841309 DOI: 10.1016/j.neuron.2012.06.009] [Citation(s) in RCA: 445] [Impact Index Per Article: 37.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/18/2012] [Indexed: 01/17/2023]
Abstract
Hubel and Wiesel began the modern study of development and plasticity of primary visual cortex (V1), discovering response properties of cortical neurons that distinguished them from their inputs and that were arranged in a functional architecture. Their findings revealed an early innate period of development and a later critical period of dramatic experience-dependent plasticity. Recent studies have used rodents to benefit from biochemistry and genetics. The roles of spontaneous neural activity and molecular signaling in innate, experience-independent development have been clarified, as have the later roles of visual experience. Plasticity produced by monocular visual deprivation (MD) has been dissected into stages governed by distinct signaling mechanisms, some of whose molecular players are known. Many crucial questions remain, but new tools for perturbing cortical cells and measuring plasticity at the level of changes in connections among identified neurons now exist. The future for the study of V1 to illuminate cortical development and plasticity is bright.
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Affiliation(s)
- J Sebastian Espinosa
- Center for Integrative Neuroscience, Department of Physiology, 675 Nelson Rising Lane, University of California, San Francisco, San Francisco, CA 94143-0444, USA
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18
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Hamilton DJ, Shepherd GM, Martone ME, Ascoli GA. An ontological approach to describing neurons and their relationships. Front Neuroinform 2012; 6:15. [PMID: 22557965 PMCID: PMC3338117 DOI: 10.3389/fninf.2012.00015] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2011] [Accepted: 04/04/2012] [Indexed: 11/13/2022] Open
Abstract
The advancement of neuroscience, perhaps one of the most information rich disciplines of all the life sciences, requires basic frameworks for organizing the vast amounts of data generated by the research community to promote novel insights and integrated understanding. Since Cajal, the neuron remains a fundamental unit of the nervous system, yet even with the explosion of information technology, we still have few comprehensive or systematic strategies for aggregating cell-level knowledge. Progress toward this goal is hampered by the multiplicity of names for cells and by lack of a consensus on the criteria for defining neuron types. However, through umbrella projects like the Neuroscience Information Framework (NIF) and the International Neuroinformatics Coordinating Facility (INCF), we have the opportunity to propose and implement an informatics infrastructure for establishing common tools and approaches to describe neurons through a standard terminology for nerve cells and a database (a Neuron Registry) where these descriptions can be deposited and compared. This article provides an overview of the problem and outlines a solution approach utilizing ontological characterizations. Based on illustrative implementation examples, we also discuss the need for consensus criteria to be adopted by the research community, and considerations on future developments. A scalable repository of neuron types will provide researchers with a resource that materially contributes to the advancement of neuroscience.
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Affiliation(s)
- David J Hamilton
- Center for Neural Informatics, Structures, & Plasticity and Molecular Neuroscience Department, Krasnow Institute for Advanced Study, George Mason University, Fairfax VA, USA
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19
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Functional profiling of neurons through cellular neuropharmacology. Proc Natl Acad Sci U S A 2012; 109:1388-95. [PMID: 22307590 DOI: 10.1073/pnas.1118833109] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We describe a functional profiling strategy to identify and characterize subtypes of neurons present in a peripheral ganglion, which should be extendable to neurons in the CNS. In this study, dissociated dorsal-root ganglion neurons from mice were exposed to various pharmacological agents (challenge compounds), while at the same time the individual responses of >100 neurons were simultaneously monitored by calcium imaging. Each challenge compound elicited responses in only a subset of dorsal-root ganglion neurons. Two general types of challenge compounds were used: agonists of receptors (ionotropic and metabotropic) that alter cytoplasmic calcium concentration (receptor-agonist challenges) and compounds that affect voltage-gated ion channels (membrane-potential challenges). Notably, among the latter are K-channel antagonists, which elicited unexpectedly diverse types of calcium responses in different cells (i.e., phenotypes). We used various challenge compounds to identify several putative neuronal subtypes on the basis of their shared and/or divergent functional, phenotypic profiles. Our results indicate that multiple receptor-agonist and membrane-potential challenges may be applied to a neuronal population to identify, characterize, and discriminate among neuronal subtypes. This experimental approach can uncover constellations of plasma membrane macromolecules that are functionally coupled to confer a specific phenotypic profile on each neuronal subtype. This experimental platform has the potential to bridge a gap between systems and molecular neuroscience with a cellular-focused neuropharmacology, ultimately leading to the identification and functional characterization of all neuronal subtypes at a given locus in the nervous system.
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20
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Langer D, Helmchen F. Post hoc immunostaining of GABAergic neuronal subtypes following in vivo two-photon calcium imaging in mouse neocortex. Pflugers Arch 2011; 463:339-54. [PMID: 22134770 PMCID: PMC3261390 DOI: 10.1007/s00424-011-1048-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2011] [Revised: 09/28/2011] [Accepted: 10/17/2011] [Indexed: 01/11/2023]
Abstract
GABAergic neurons in the neocortex are diverse with regard to morphology, physiology, and axonal targeting pattern, indicating functional specializations within the cortical microcircuitry. Little information is available, however, about functional properties of distinct subtypes of GABAergic neurons in the intact brain. Here, we combined in vivo two-photon calcium imaging in supragranular layers of the mouse neocortex with post hoc immunohistochemistry against the three calcium-binding proteins parvalbumin, calretinin, and calbindin in order to assign subtype marker profiles to neuronal activity. Following coronal sectioning of fixed brains, we matched cells in corresponding volumes of image stacks acquired in vivo and in fixed brain slices. In GAD67-GFP mice, more than 95% of the GABAergic cells could be unambiguously matched, even in large volumes comprising more than a thousand interneurons. Triple immunostaining revealed a depth-dependent distribution of interneuron subtypes with increasing abundance of PV-positive neurons with depth. Most importantly, the triple-labeling approach was compatible with previous in vivo calcium imaging following bulk loading of Oregon Green 488 BAPTA-1, which allowed us to classify spontaneous calcium transients recorded in vivo according to the neurochemically defined GABAergic subtypes. Moreover, we demonstrate that post hoc immunostaining can also be applied to wild-type mice expressing the genetically encoded calcium indicator Yellow Cameleon 3.60 in cortical neurons. Our approach is a general and flexible method to distinguish GABAergic subtypes in cell populations previously imaged in the living animal. It should thus facilitate dissecting the functional roles of these subtypes in neural circuitry.
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Affiliation(s)
- Dominik Langer
- Department of Neurophysiology, Brain Research Institute, University of Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland
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21
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Kleinfeld D, Blinder P, Drew PJ, Driscoll JD, Muller A, Tsai PS, Shih AY. A guide to delineate the logic of neurovascular signaling in the brain. FRONTIERS IN NEUROENERGETICS 2011; 3:1. [PMID: 21559095 PMCID: PMC3085135 DOI: 10.3389/fnene.2011.00001] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/08/2010] [Accepted: 04/11/2011] [Indexed: 01/26/2023]
Abstract
The neurovascular system may be viewed as a distributed nervous system within the brain. It transforms local neuronal activity into a change in the tone of smooth muscle that lines the walls of arterioles and microvessels. We review the current state of neurovascular coupling, with an emphasis on signaling molecules that convey information from neurons to neighboring vessels. At the level of neocortex, this coupling is mediated by: (i) a likely direct interaction with inhibitory neurons, (ii) indirect interaction, via astrocytes, with excitatory neurons, and (iii) fiber tracts from subcortical layers. Substantial evidence shows that control involves competition between signals that promote vasoconstriction versus vasodilation. Consistent with this picture is evidence that, under certain circumstances, increased neuronal activity can lead to vasoconstriction rather than vasodilation. This confounds naïve interpretations of functional brain images. We discuss experimental approaches to detect signaling molecules in vivo with the goal of formulating an empirical basis for the observed logic of neurovascular control.
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Affiliation(s)
- David Kleinfeld
- Department of Physics, University of California San Diego La Jolla, CA, USA
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Bridging the gaps between synapses, circuits, and behavior. ACTA ACUST UNITED AC 2010; 17:607-15. [PMID: 20609410 DOI: 10.1016/j.chembiol.2010.06.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2010] [Revised: 06/04/2010] [Accepted: 06/04/2010] [Indexed: 01/28/2023]
Abstract
The decade of the brain may have come and gone, but the final frontier, cracking the neuronal code, still lies ahead. Today, new technologies that allow precise spatiotemporal remote control over the activity of genetically defined populations of neurons within intact neural circuits are providing a means of obtaining a functional wiring diagram of the mammalian brain, bringing us one step closer to understanding precisely how neuronal activity codes for perception, thought, emotion, and action. These technologies and the design principles underlying them are reviewed herein.
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