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Stentiford R, Knight JC, Nowotny T, Philippides A, Graham P. Estimating orientation in natural scenes: A spiking neural network model of the insect central complex. PLoS Comput Biol 2024; 20:e1011913. [PMID: 39146374 PMCID: PMC11349202 DOI: 10.1371/journal.pcbi.1011913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2024] [Revised: 08/27/2024] [Accepted: 07/24/2024] [Indexed: 08/17/2024] Open
Abstract
The central complex of insects contains cells, organised as a ring attractor, that encode head direction. The 'bump' of activity in the ring can be updated by idiothetic cues and external sensory information. Plasticity at the synapses between these cells and the ring neurons, that are responsible for bringing sensory information into the central complex, has been proposed to form a mapping between visual cues and the heading estimate which allows for more accurate tracking of the current heading, than if only idiothetic information were used. In Drosophila, ring neurons have well characterised non-linear receptive fields. In this work we produce synthetic versions of these visual receptive fields using a combination of excitatory inputs and mutual inhibition between ring neurons. We use these receptive fields to bring visual information into a spiking neural network model of the insect central complex based on the recently published Drosophila connectome. Previous modelling work has focused on how this circuit functions as a ring attractor using the same type of simple visual cues commonly used experimentally. While we initially test the model on these simple stimuli, we then go on to apply the model to complex natural scenes containing multiple conflicting cues. We show that this simple visual filtering provided by the ring neurons is sufficient to form a mapping between heading and visual features and maintain the heading estimate in the absence of angular velocity input. The network is successful at tracking heading even when presented with videos of natural scenes containing conflicting information from environmental changes and translation of the camera.
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Affiliation(s)
- Rachael Stentiford
- Department of Informatics, University of Sussex, Brighton, United Kingdom
| | - James C. Knight
- Department of Informatics, University of Sussex, Brighton, United Kingdom
| | - Thomas Nowotny
- Department of Informatics, University of Sussex, Brighton, United Kingdom
| | - Andrew Philippides
- Department of Informatics, University of Sussex, Brighton, United Kingdom
| | - Paul Graham
- School of Life Sciences, University of Sussex, Brighton, United Kingdom
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2
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Koch S, Kandimalla P, Padilla E, Kaur S, Kaur R, Nguyen M, Nelson A, Khalsa S, Younossi-Hartenstein A, Hartenstein V. Structural changes shaping the Drosophila ellipsoid body ER-neurons during development and aging. Dev Biol 2024; 516:96-113. [PMID: 39089472 DOI: 10.1016/j.ydbio.2024.07.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2024] [Revised: 07/25/2024] [Accepted: 07/29/2024] [Indexed: 08/04/2024]
Abstract
The ellipsoid body (EB) of the insect brain performs pivotal functions in controlling navigation. Input and output of the EB is provided by multiple classes of R-neurons (now referred to as ER-neurons) and columnar neurons which interact with each other in a stereotypical and spatially highly ordered manner. The developmental mechanisms that control the connectivity and topography of EB neurons are largely unknown. One indispensable prerequisite to unravel these mechanisms is to document in detail the sequence of events that shape EB neurons during their development. In this study, we analyzed the development of the Drosophila EB. In addition to globally following the ER-neuron and columnar neuron (sub)classes in the spatial context of their changing environment we performed a single cell analysis using the multi-color flip out (MCFO) system to analyze the developmental trajectory of ER-neurons at different pupal stages, young adults (4d) and aged adults (∼60d). We show that the EB develops as a merger of two distinct elements, a posterior and anterior EB primordium (prEBp and prEBa, respectively. ER-neurons belonging to different subclasses form growth cones and filopodia that associate with the prEBp and prEBa in a pattern that, from early pupal stages onward, foreshadows their mature structure. Filopodia of all ER-subclasses are initially much longer than the dendritic and terminal axonal branches they give rise to, and are pruned back during late pupal stages. Interestingly, extraneous branches, particularly significant in the dendritic domain, are a hallmark of ER-neuron structure in aged brains. Aging is also associated with a decline in synaptic connectivity from columnar neurons, as well as upregulation of presynaptic protein (Brp) in ER-neurons. Our findings advance the EB (and ER-neurons) as a favorable system to visualize and quantify the development and age-related decline of a complex neuronal circuitry.
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Affiliation(s)
- Sandra Koch
- Department of Molecular Cell and Developmental Biology, University of California Los Angeles, Los Angeles, CA, 90095, USA
| | - Pratyush Kandimalla
- Department of Molecular Cell and Developmental Biology, University of California Los Angeles, Los Angeles, CA, 90095, USA; Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Eddie Padilla
- Department of Molecular Cell and Developmental Biology, University of California Los Angeles, Los Angeles, CA, 90095, USA
| | - Sabrina Kaur
- Department of Molecular Cell and Developmental Biology, University of California Los Angeles, Los Angeles, CA, 90095, USA
| | - Rabina Kaur
- Department of Molecular Cell and Developmental Biology, University of California Los Angeles, Los Angeles, CA, 90095, USA
| | - My Nguyen
- Department of Molecular Cell and Developmental Biology, University of California Los Angeles, Los Angeles, CA, 90095, USA
| | - Annie Nelson
- Department of Molecular Cell and Developmental Biology, University of California Los Angeles, Los Angeles, CA, 90095, USA
| | - Satkartar Khalsa
- Department of Molecular Cell and Developmental Biology, University of California Los Angeles, Los Angeles, CA, 90095, USA
| | - Amelia Younossi-Hartenstein
- Department of Molecular Cell and Developmental Biology, University of California Los Angeles, Los Angeles, CA, 90095, USA
| | - Volker Hartenstein
- Department of Molecular Cell and Developmental Biology, University of California Los Angeles, Los Angeles, CA, 90095, USA.
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3
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Jiang X, Dimitriou E, Grabe V, Sun R, Chang H, Zhang Y, Gershenzon J, Rybak J, Hansson BS, Sachse S. Ring-shaped odor coding in the antennal lobe of migratory locusts. Cell 2024; 187:3973-3991.e24. [PMID: 38897195 DOI: 10.1016/j.cell.2024.05.036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Revised: 04/05/2024] [Accepted: 05/20/2024] [Indexed: 06/21/2024]
Abstract
The representation of odors in the locust antennal lobe with its >2,000 glomeruli has long remained a perplexing puzzle. We employed the CRISPR-Cas9 system to generate transgenic locusts expressing the genetically encoded calcium indicator GCaMP in olfactory sensory neurons. Using two-photon functional imaging, we mapped the spatial activation patterns representing a wide range of ecologically relevant odors across all six developmental stages. Our findings reveal a functionally ring-shaped organization of the antennal lobe composed of specific glomerular clusters. This configuration establishes an odor-specific chemotopic representation by encoding different chemical classes and ecologically distinct odors in the form of glomerular rings. The ring-shaped glomerular arrangement, which we confirm by selective targeting of OR70a-expressing sensory neurons, occurs throughout development, and the odor-coding pattern within the glomerular population is consistent across developmental stages. Mechanistically, this unconventional spatial olfactory code reflects the locust-specific and multiplexed glomerular innervation pattern of the antennal lobe.
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Affiliation(s)
- Xingcong Jiang
- Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, 07745 Jena, Germany; Research Group Olfactory Coding, Max Planck Institute for Chemical Ecology, 07745 Jena, Germany
| | - Eleftherios Dimitriou
- Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, 07745 Jena, Germany
| | - Veit Grabe
- Microscopic Service Group, Max Planck Institute for Chemical Ecology, 07745 Jena, Germany
| | - Ruo Sun
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, 07745 Jena, Germany
| | - Hetan Chang
- Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, 07745 Jena, Germany
| | - Yifu Zhang
- Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, 07745 Jena, Germany
| | - Jonathan Gershenzon
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, 07745 Jena, Germany
| | - Jürgen Rybak
- Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, 07745 Jena, Germany
| | - Bill S Hansson
- Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, 07745 Jena, Germany.
| | - Silke Sachse
- Research Group Olfactory Coding, Max Planck Institute for Chemical Ecology, 07745 Jena, Germany.
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4
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Eckstein N, Bates AS, Champion A, Du M, Yin Y, Schlegel P, Lu AKY, Rymer T, Finley-May S, Paterson T, Parekh R, Dorkenwald S, Matsliah A, Yu SC, McKellar C, Sterling A, Eichler K, Costa M, Seung S, Murthy M, Hartenstein V, Jefferis GSXE, Funke J. Neurotransmitter classification from electron microscopy images at synaptic sites in Drosophila melanogaster. Cell 2024; 187:2574-2594.e23. [PMID: 38729112 PMCID: PMC11106717 DOI: 10.1016/j.cell.2024.03.016] [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] [Received: 04/02/2023] [Revised: 10/04/2023] [Accepted: 03/13/2024] [Indexed: 05/12/2024]
Abstract
High-resolution electron microscopy of nervous systems has enabled the reconstruction of synaptic connectomes. However, we do not know the synaptic sign for each connection (i.e., whether a connection is excitatory or inhibitory), which is implied by the released transmitter. We demonstrate that artificial neural networks can predict transmitter types for presynapses from electron micrographs: a network trained to predict six transmitters (acetylcholine, glutamate, GABA, serotonin, dopamine, octopamine) achieves an accuracy of 87% for individual synapses, 94% for neurons, and 91% for known cell types across a D. melanogaster whole brain. We visualize the ultrastructural features used for prediction, discovering subtle but significant differences between transmitter phenotypes. We also analyze transmitter distributions across the brain and find that neurons that develop together largely express only one fast-acting transmitter (acetylcholine, glutamate, or GABA). We hope that our publicly available predictions act as an accelerant for neuroscientific hypothesis generation for the fly.
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Affiliation(s)
- Nils Eckstein
- HHMI Janelia Research Campus, Ashburn, VA, USA; Institute of Neuroinformatics UZH/ETHZ, Zurich, Switzerland
| | - Alexander Shakeel Bates
- Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, UK; Centre for Neural Circuits and Behaviour, The University of Oxford, Tinsley Building, Mansfield Road, Oxford OX1 3SR, UK; Department of Neurobiology and Howard Hughes Medical Institute, Harvard Medical School, Boston, MA, USA
| | - Andrew Champion
- Drosophila Connectomics Group, Department of Zoology, University of Cambridge, Cambridge, UK
| | - Michelle Du
- HHMI Janelia Research Campus, Ashburn, VA, USA
| | - Yijie Yin
- Drosophila Connectomics Group, Department of Zoology, University of Cambridge, Cambridge, UK
| | - Philipp Schlegel
- Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, UK; Drosophila Connectomics Group, Department of Zoology, University of Cambridge, Cambridge, UK
| | | | | | | | | | | | - Sven Dorkenwald
- Princeton Neuroscience Institute, Princeton University, Princeton, NJ, USA
| | - Arie Matsliah
- Princeton Neuroscience Institute, Princeton University, Princeton, NJ, USA
| | - Szi-Chieh Yu
- Princeton Neuroscience Institute, Princeton University, Princeton, NJ, USA
| | - Claire McKellar
- Princeton Neuroscience Institute, Princeton University, Princeton, NJ, USA
| | - Amy Sterling
- Princeton Neuroscience Institute, Princeton University, Princeton, NJ, USA
| | - Katharina Eichler
- Drosophila Connectomics Group, Department of Zoology, University of Cambridge, Cambridge, UK
| | - Marta Costa
- Drosophila Connectomics Group, Department of Zoology, University of Cambridge, Cambridge, UK
| | - Sebastian Seung
- Princeton Neuroscience Institute, Princeton University, Princeton, NJ, USA
| | - Mala Murthy
- Princeton Neuroscience Institute, Princeton University, Princeton, NJ, USA
| | - Volker Hartenstein
- Department of Molecular Cell and Developmental Biology, University of California, Los Angeles, Los Angeles, CA, USA
| | - Gregory S X E Jefferis
- Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, UK; Drosophila Connectomics Group, Department of Zoology, University of Cambridge, Cambridge, UK.
| | - Jan Funke
- HHMI Janelia Research Campus, Ashburn, VA, USA.
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5
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Dopp J, Ortega A, Davie K, Poovathingal S, Baz ES, Liu S. Single-cell transcriptomics reveals that glial cells integrate homeostatic and circadian processes to drive sleep-wake cycles. Nat Neurosci 2024; 27:359-372. [PMID: 38263460 PMCID: PMC10849968 DOI: 10.1038/s41593-023-01549-4] [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] [Received: 01/15/2023] [Accepted: 12/07/2023] [Indexed: 01/25/2024]
Abstract
The sleep-wake cycle is determined by circadian and sleep homeostatic processes. However, the molecular impact of these processes and their interaction in different brain cell populations are unknown. To fill this gap, we profiled the single-cell transcriptome of adult Drosophila brains across the sleep-wake cycle and four circadian times. We show cell type-specific transcriptomic changes, with glia displaying the largest variation. Glia are also among the few cell types whose gene expression correlates with both sleep homeostat and circadian clock. The sleep-wake cycle and sleep drive level affect the expression of clock gene regulators in glia, and disrupting clock genes specifically in glia impairs homeostatic sleep rebound after sleep deprivation. These findings provide a comprehensive view of the effects of sleep homeostatic and circadian processes on distinct cell types in an entire animal brain and reveal glia as an interaction site of these two processes to determine sleep-wake dynamics.
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Affiliation(s)
- Joana Dopp
- Center for Brain & Disease Research, VIB-KU Leuven, Leuven, Belgium
- Department of Neurosciences, KU Leuven, Leuven, Belgium
- Leuven Brain Institute, KU Leuven, Leuven, Belgium
| | - Antonio Ortega
- Center for Brain & Disease Research, VIB-KU Leuven, Leuven, Belgium
- Department of Neurosciences, KU Leuven, Leuven, Belgium
- Leuven Brain Institute, KU Leuven, Leuven, Belgium
| | - Kristofer Davie
- Center for Brain & Disease Research, VIB-KU Leuven, Leuven, Belgium
- Leuven Brain Institute, KU Leuven, Leuven, Belgium
| | - Suresh Poovathingal
- Center for Brain & Disease Research, VIB-KU Leuven, Leuven, Belgium
- Leuven Brain Institute, KU Leuven, Leuven, Belgium
| | - El-Sayed Baz
- Center for Brain & Disease Research, VIB-KU Leuven, Leuven, Belgium
- Leuven Brain Institute, KU Leuven, Leuven, Belgium
- Zoology Department, Faculty of Science, Suez Canal University, Ismailia, Egypt
| | - Sha Liu
- Center for Brain & Disease Research, VIB-KU Leuven, Leuven, Belgium.
- Department of Neurosciences, KU Leuven, Leuven, Belgium.
- Leuven Brain Institute, KU Leuven, Leuven, Belgium.
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6
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Garner D, Kind E, Nern A, Houghton L, Zhao A, Sancer G, Rubin GM, Wernet MF, Kim SS. Connectomic reconstruction predicts the functional organization of visual inputs to the navigation center of the Drosophila brain. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.29.569241. [PMID: 38076786 PMCID: PMC10705420 DOI: 10.1101/2023.11.29.569241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/22/2023]
Abstract
Many animals, including humans, navigate their surroundings by visual input, yet we understand little about how visual information is transformed and integrated by the navigation system. In Drosophila melanogaster, compass neurons in the donut-shaped ellipsoid body of the central complex generate a sense of direction by integrating visual input from ring neurons, a part of the anterior visual pathway (AVP). Here, we densely reconstruct all neurons in the AVP using FlyWire, an AI-assisted tool for analyzing electron-microscopy data. The AVP comprises four neuropils, sequentially linked by three major classes of neurons: MeTu neurons, which connect the medulla in the optic lobe to the small unit of anterior optic tubercle (AOTUsu) in the central brain; TuBu neurons, which connect the anterior optic tubercle to the bulb neuropil; and ring neurons, which connect the bulb to the ellipsoid body. Based on neuronal morphologies, connectivity between different neural classes, and the locations of synapses, we identified non-overlapping channels originating from four types of MeTu neurons, which we further divided into ten subtypes based on the presynaptic connections in medulla and postsynaptic connections in AOTUsu. To gain an objective measure of the natural variation within the pathway, we quantified the differences between anterior visual pathways from both hemispheres and between two electron-microscopy datasets. Furthermore, we infer potential visual features and the visual area from which any given ring neuron receives input by combining the connectivity of the entire AVP, the MeTu neurons' dendritic fields, and presynaptic connectivity in the optic lobes. These results provide a strong foundation for understanding how distinct visual features are extracted and transformed across multiple processing stages to provide critical information for computing the fly's sense of direction.
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Affiliation(s)
- Dustin Garner
- Molecular, Cellular, and Developmental Biology, University of California Santa Barbara, Santa Barbara, CA, USA
| | - Emil Kind
- Department of Biology, Freie Universität Berlin, Berlin, Germany
| | - Aljoscha Nern
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Lucy Houghton
- Molecular, Cellular, and Developmental Biology, University of California Santa Barbara, Santa Barbara, CA, USA
| | - Arthur Zhao
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Gizem Sancer
- Department of Biology, Freie Universität Berlin, Berlin, Germany
| | - Gerald M. Rubin
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | | | - Sung Soo Kim
- Molecular, Cellular, and Developmental Biology, University of California Santa Barbara, Santa Barbara, CA, USA
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7
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Posnien N, Hunnekuhl VS, Bucher G. Gene expression mapping of the neuroectoderm across phyla - conservation and divergence of early brain anlagen between insects and vertebrates. eLife 2023; 12:e92242. [PMID: 37750868 PMCID: PMC10522337 DOI: 10.7554/elife.92242] [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] [Received: 09/07/2023] [Accepted: 09/18/2023] [Indexed: 09/27/2023] Open
Abstract
Gene expression has been employed for homologizing body regions across bilateria. The molecular comparison of vertebrate and fly brains has led to a number of disputed homology hypotheses. Data from the fly Drosophila melanogaster have recently been complemented by extensive data from the red flour beetle Tribolium castaneum with its more insect-typical development. In this review, we revisit the molecular mapping of the neuroectoderm of insects and vertebrates to reconsider homology hypotheses. We claim that the protocerebrum is non-segmental and homologous to the vertebrate fore- and midbrain. The boundary between antennal and ocular regions correspond to the vertebrate mid-hindbrain boundary while the deutocerebrum represents the anterior-most ganglion with serial homology to the trunk. The insect head placode is shares common embryonic origin with the vertebrate adenohypophyseal placode. Intriguingly, vertebrate eyes develop from a different region compared to the insect compound eyes calling organ homology into question. Finally, we suggest a molecular re-definition of the classic concepts of archi- and prosocerebrum.
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Affiliation(s)
- Nico Posnien
- Department of Developmental Biology, Johann-Friedrich-Blumenbach Institute, University GoettingenGöttingenGermany
| | - Vera S Hunnekuhl
- Department of Evolutionary Developmental Genetics, Johann-Friedrich-Blumenbach Institute, University of GöttingenGöttingenGermany
| | - Gregor Bucher
- Department of Evolutionary Developmental Genetics, Johann-Friedrich-Blumenbach Institute, University of GöttingenGöttingenGermany
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8
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Singh P, Aleman A, Omoto JJ, Nguyen BC, Kandimalla P, Hartenstein V, Donlea JM. Examining Sleep Modulation by Drosophila Ellipsoid Body Neurons. eNeuro 2023; 10:ENEURO.0281-23.2023. [PMID: 37679041 PMCID: PMC10523840 DOI: 10.1523/eneuro.0281-23.2023] [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] [Received: 08/06/2023] [Accepted: 08/10/2023] [Indexed: 09/09/2023] Open
Abstract
Recent work in Drosophila has uncovered several neighboring classes of sleep-regulatory neurons within the central complex. However, the logic of connectivity and network motifs remains limited by the incomplete examination of relevant cell types. Using a recent genetic-anatomic classification of ellipsoid body ring neurons, we conducted a thermogenetic screen in female flies to assess sleep/wake behavior and identified two wake-promoting drivers that label ER3d neurons and two sleep-promoting drivers that express in ER3m cells. We then used intersectional genetics to refine driver expression patterns. Activation of ER3d cells shortened sleep bouts, suggesting a key role in sleep maintenance. While sleep-promoting drivers from our mini-screen label overlapping ER3m neurons, intersectional strategies cannot rule out sleep regulatory roles for additional neurons in their expression patterns. Suppressing GABA synthesis in ER3m neurons prevents postinjury sleep, and GABAergic ER3d cells are required for thermogenetically induced wakefulness. Finally, we use an activity-dependent fluorescent reporter for putative synaptic contacts to embed these neurons within the known sleep-regulatory network. ER3m and ER3d neurons may receive connections from wake-active Helicon/ExR1 cells, and ER3m neurons likely inhibit ER3d neurons. Together, these data suggest a neural mechanism by which previously uncharacterized circuit elements stabilize sleep-wake states.
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Affiliation(s)
- Prabhjit Singh
- Department of Neurobiology, David Geffen School of Medicine, University of California-Los Angeles, Los Angeles, California 90095
| | - Abigail Aleman
- Department of Neurobiology, David Geffen School of Medicine, University of California-Los Angeles, Los Angeles, California 90095
- Molecular, Cellular & Integrative Physiology Interdepartmental Program, University of California-Los Angeles, Los Angeles, California 90095
| | - Jaison Jiro Omoto
- Department of Neurobiology, David Geffen School of Medicine, University of California-Los Angeles, Los Angeles, California 90095
| | - Bao-Chau Nguyen
- Department of Molecular, Cell, & Developmental Biology, University of California-Los Angeles, Los Angeles, California 90095
| | - Pratyush Kandimalla
- Department of Molecular, Cell, & Developmental Biology, University of California-Los Angeles, Los Angeles, California 90095
| | - Volker Hartenstein
- Department of Molecular, Cell, & Developmental Biology, University of California-Los Angeles, Los Angeles, California 90095
| | - Jeffrey M Donlea
- Department of Neurobiology, David Geffen School of Medicine, University of California-Los Angeles, Los Angeles, California 90095
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9
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Homberg U, Kirchner M, Kowalewski K, Pitz V, Kinoshita M, Kern M, Seyfarth J. Comparative morphology of serotonin-immunoreactive neurons innervating the central complex in the brain of dicondylian insects. J Comp Neurol 2023. [PMID: 37478205 DOI: 10.1002/cne.25529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 06/28/2023] [Accepted: 07/08/2023] [Indexed: 07/23/2023]
Abstract
Serotonin (5-hydroxytryptamine) acts as a widespread neuromodulator in the nervous system of vertebrates and invertebrates. In insects, it promotes feeding, enhances olfactory sensitivity, modulates aggressive behavior, and, in the central complex of Drosophila, serves a role in sleep homeostasis. In addition to a role in sleep-wake regulation, the central complex has a prominent role in spatial orientation, goal-directed locomotion, and navigation vector memory. To further understand the role of serotonergic signaling in this brain area, we analyzed the distribution and identity of serotonin-immunoreactive neurons across a wide range of insect species. While one bilateral pair of tangential neurons innervating the central body was present in all species studied, a second type was labeled in all neopterans but not in dragonflies and firebrats. Both cell types show conserved major fiber trajectories but taxon-specific differences in dendritic targets outside the central body and axonal terminals in the central body, noduli, and lateral accessory lobes. In addition, numerous tangential neurons of the protocerebral bridge were labeled in all studied polyneopteran species except for Phasmatodea, but not in Holometabola. Lepidoptera and Diptera showed additional labeling of two bilateral pairs of neurons of a third type. The presence of serotonin in systems of columnar neurons apparently evolved independently in dragonflies and desert locusts. The data suggest distinct evolutionary changes in the composition of serotonin-immunolabeled neurons of the central complex and provides a promising basis for a phylogenetic study in a wider range of arthropod species.
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Affiliation(s)
- Uwe Homberg
- Department of Biology, Animal Physiology, Philipps-Universität Marburg, Marburg, Germany
- Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus Liebig University Giessen, Marburg, Germany
| | - Michelle Kirchner
- Department of Biology, Animal Physiology, Philipps-Universität Marburg, Marburg, Germany
| | - Kevin Kowalewski
- Department of Biology, Animal Physiology, Philipps-Universität Marburg, Marburg, Germany
| | - Vanessa Pitz
- Department of Biology, Animal Physiology, Philipps-Universität Marburg, Marburg, Germany
| | - Michiyo Kinoshita
- Laboratory of Neuroethology, SOKENDAI, The Graduate University for Advanced Studies, Hayama, Japan
| | - Martina Kern
- Department of Biology, Animal Physiology, Philipps-Universität Marburg, Marburg, Germany
| | - Jutta Seyfarth
- Department of Biology, Animal Physiology, Philipps-Universität Marburg, Marburg, Germany
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10
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Mitchell R, Shaverdian S, Dacke M, Webb B. A model of cue integration as vector summation in the insect brain. Proc Biol Sci 2023; 290:20230767. [PMID: 37357865 PMCID: PMC10291719 DOI: 10.1098/rspb.2023.0767] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 05/30/2023] [Indexed: 06/27/2023] Open
Abstract
Ball-rolling dung beetles are known to integrate multiple cues in order to facilitate their straight-line orientation behaviour. Recent work has suggested that orientation cues are integrated according to a vector sum, that is, compass cues are represented by vectors and summed to give a combined orientation estimate. Further, cue weight (vector magnitude) appears to be set according to cue reliability. This is consistent with the popular Bayesian view of cue integration: cues are integrated to reduce or minimize an agent's uncertainty about the external world. Integration of orientation cues is believed to occur at the input to the insect central complex. Here, we demonstrate that a model of the head direction circuit of the central complex, including plasticity in input synapses, can act as a substrate for cue integration as vector summation. Further, we show that cue influence is not necessarily driven by cue reliability. Finally, we present a dung beetle behavioural experiment which, in combination with simulation, strongly suggests that these beetles do not weight cues according to reliability. We suggest an alternative strategy whereby cues are weighted according to relative contrast, which can also explain previous results.
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Affiliation(s)
- Robert Mitchell
- Institute for Perception, Action, and Behaviour, The University of Edinburgh School of Informatics, Edinburgh, Edinburgh EH8 9AB, UK
| | - Shahrzad Shaverdian
- Lund Vision Group, Department of Biology, Lund University, Lund SE-223 62, Sweden
| | - Marie Dacke
- Lund Vision Group, Department of Biology, Lund University, Lund SE-223 62, Sweden
| | - Barbara Webb
- Institute for Perception, Action, and Behaviour, The University of Edinburgh School of Informatics, Edinburgh, Edinburgh EH8 9AB, UK
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11
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Duan W, Zhang Y, Zhang X, Yang J, Shan H, Liu L, Wei H. A Visual Pathway into Central Complex for High-Frequency Motion-Defined Bars in Drosophila. J Neurosci 2023; 43:4821-4836. [PMID: 37290936 PMCID: PMC10312062 DOI: 10.1523/jneurosci.0128-23.2023] [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: 01/23/2023] [Revised: 05/31/2023] [Accepted: 06/02/2023] [Indexed: 06/10/2023] Open
Abstract
Relative motion breaks a camouflaged target from a same-textured background, thus eliciting discrimination of a motion-defined object. Ring (R) neurons are critical components in the Drosophila central complex, which has been implicated in multiple visually guided behaviors. Using two-photon calcium imaging with female flies, we demonstrated that a specific population of R neurons that innervate the superior domain of bulb neuropil, termed superior R neurons, encoded a motion-defined bar with high spatial frequency contents. Upstream superior tuberculo-bulbar (TuBu) neurons transmitted visual signals by releasing acetylcholine within synapses connected with superior R neurons. Blocking TuBu or R neurons impaired tracking performance of the bar, which reveals their importance in motion-defined feature encoding. Additionally, the presentation of a low spatial frequency luminance-defined bar evoked consistent excitation in R neurons of the superior bulb, whereas either excited or inhibited responses were evoked in the inferior bulb. The distinct properties of the responses to the two bar stimuli indicate there is a functional division between the bulb subdomains. Moreover, physiological and behavioral tests with restricted lines suggest that R4d neurons play a vital role in tracking motion-defined bars. We conclude that the central complex receives the motion-defined features via a visual pathway from superior TuBu to R neurons and might encode different visual features via distinct response patterns at the population level, thereby driving visually guided behaviors.SIGNIFICANCE STATEMENT Animals could discriminate a motion-defined object that is indistinguishable with a same-textured background until it moves, but little is known about the underlying neural mechanisms. In this study, we identified that R neurons and their upstream partners, TuBu neurons, innervating the superior bulb of Drosophila central brain are involved in the discrimination of high-frequency motion-defined bars. Our study provides new evidence that R neurons receive multiple visual inputs from distinct upstream neurons, indicating a population coding mechanism for the fly central brain to discriminate diverse visual features. These results build progress in unraveling neural substrates for visually guided behaviors.
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Affiliation(s)
- Wenlan Duan
- State Key Laboratory of Brain and Cognitive Science, Chinese Academy of Sciences Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
- College of Life Sciences, University of the Chinese Academy of Sciences, Beijing 100039, China
| | - Yihao Zhang
- State Key Laboratory of Brain and Cognitive Science, Chinese Academy of Sciences Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
- College of Life Sciences, University of the Chinese Academy of Sciences, Beijing 100039, China
| | - Xin Zhang
- State Key Laboratory of Brain and Cognitive Science, Chinese Academy of Sciences Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
- College of Life Sciences, University of the Chinese Academy of Sciences, Beijing 100039, China
| | - Jihua Yang
- State Key Laboratory of Brain and Cognitive Science, Chinese Academy of Sciences Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
- College of Life Sciences, University of the Chinese Academy of Sciences, Beijing 100039, China
| | - Heying Shan
- State Key Laboratory of Brain and Cognitive Science, Chinese Academy of Sciences Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Li Liu
- State Key Laboratory of Brain and Cognitive Science, Chinese Academy of Sciences Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
- College of Life Sciences, University of the Chinese Academy of Sciences, Beijing 100039, China
- Chinese Academy of Sciences Key Laboratory of Mental Health, Beijing 100101, China
| | - Hongying Wei
- State Key Laboratory of Brain and Cognitive Science, Chinese Academy of Sciences Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
- College of Life Sciences, University of the Chinese Academy of Sciences, Beijing 100039, China
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12
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Gendron CM, Chakraborty TS, Duran C, Dono T, Pletcher SD. Ring neurons in the Drosophila central complex act as a rheostat for sensory modulation of aging. PLoS Biol 2023; 21:e3002149. [PMID: 37310911 PMCID: PMC10263353 DOI: 10.1371/journal.pbio.3002149] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Accepted: 05/03/2023] [Indexed: 06/15/2023] Open
Abstract
Sensory perception modulates aging, yet we know little about how. An understanding of the neuronal mechanisms through which animals orchestrate biological responses to relevant sensory inputs would provide insight into the control systems that may be important for modulating lifespan. Here, we provide new awareness into how the perception of dead conspecifics, or death perception, which elicits behavioral and physiological effects in many different species, affects lifespan in the fruit fly, Drosophila melanogaster. Previous work demonstrated that cohousing Drosophila with dead conspecifics decreases fat stores, reduces starvation resistance, and accelerates aging in a manner that requires both sight and the serotonin receptor 5-HT2A. In this manuscript, we demonstrate that a discrete, 5-HT2A-expressing neural population in the ellipsoid body (EB) of the Drosophila central complex, identified as R2/R4 neurons, acts as a rheostat and plays an important role in transducing sensory information about the presence of dead individuals to modulate lifespan. Expression of the insulin-responsive transcription factor foxo in R2/R4 neurons and insulin-like peptides dilp3 and dilp5, but not dilp2, are required, with the latter likely altered in median neurosecretory cells (MNCs) after R2/R4 neuronal activation. These data generate new insights into the neural underpinnings of how perceptive events may impact aging and physiology across taxa.
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Affiliation(s)
- Christi M. Gendron
- Department of Molecular and Integrative Physiology and Geriatrics Center, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Tuhin S. Chakraborty
- Department of Molecular and Integrative Physiology and Geriatrics Center, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Cathryn Duran
- Department of Molecular and Integrative Physiology and Geriatrics Center, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Thomas Dono
- Department of Molecular and Integrative Physiology and Geriatrics Center, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Scott D. Pletcher
- Department of Molecular and Integrative Physiology and Geriatrics Center, University of Michigan, Ann Arbor, Michigan, United States of America
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13
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Currier TA, Pang MM, Clandinin TR. Visual processing in the fly, from photoreceptors to behavior. Genetics 2023; 224:iyad064. [PMID: 37128740 PMCID: PMC10213501 DOI: 10.1093/genetics/iyad064] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Accepted: 03/22/2023] [Indexed: 05/03/2023] Open
Abstract
Originally a genetic model organism, the experimental use of Drosophila melanogaster has grown to include quantitative behavioral analyses, sophisticated perturbations of neuronal function, and detailed sensory physiology. A highlight of these developments can be seen in the context of vision, where pioneering studies have uncovered fundamental and generalizable principles of sensory processing. Here we begin with an overview of vision-guided behaviors and common methods for probing visual circuits. We then outline the anatomy and physiology of brain regions involved in visual processing, beginning at the sensory periphery and ending with descending motor control. Areas of focus include contrast and motion detection in the optic lobe, circuits for visual feature selectivity, computations in support of spatial navigation, and contextual associative learning. Finally, we look to the future of fly visual neuroscience and discuss promising topics for further study.
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Affiliation(s)
- Timothy A Currier
- Department of Neurobiology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Michelle M Pang
- Department of Neurobiology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Thomas R Clandinin
- Department of Neurobiology, Stanford University School of Medicine, Stanford, CA 94305, USA
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14
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Kandimalla P, Omoto JJ, Hong EJ, Hartenstein V. Lineages to circuits: the developmental and evolutionary architecture of information channels into the central complex. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2023:10.1007/s00359-023-01616-y. [PMID: 36932234 DOI: 10.1007/s00359-023-01616-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 01/27/2023] [Accepted: 01/28/2023] [Indexed: 03/19/2023]
Abstract
The representation and integration of internal and external cues is crucial for any organism to execute appropriate behaviors. In insects, a highly conserved region of the brain, the central complex (CX), functions in the representation of spatial information and behavioral states, as well as the transformation of this information into desired navigational commands. How does this relatively invariant structure enable the incorporation of information from the diversity of anatomical, behavioral, and ecological niches occupied by insects? Here, we examine the input channels to the CX in the context of their development and evolution. Insect brains develop from ~ 100 neuroblasts per hemisphere that divide systematically to form "lineages" of sister neurons, that project to their target neuropils along anatomically characteristic tracts. Overlaying this developmental tract information onto the recently generated Drosophila "hemibrain" connectome and integrating this information with the anatomical and physiological recording of neurons in other species, we observe neuropil and lineage-specific innervation, connectivity, and activity profiles in CX input channels. We posit that the proliferative potential of neuroblasts and the lineage-based architecture of information channels enable the modification of neural networks across existing, novel, and deprecated modalities in a species-specific manner, thus forming the substrate for the evolution and diversification of insect navigational circuits.
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Affiliation(s)
- Pratyush Kandimalla
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA. .,Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles, CA, USA.
| | - Jaison Jiro Omoto
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA.,Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles, CA, USA
| | - Elizabeth J Hong
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Volker Hartenstein
- Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles, CA, USA
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15
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Gajardo I, Guerra S, Campusano JM. Navigating Like a Fly: Drosophila melanogaster as a Model to Explore the Contribution of Serotonergic Neurotransmission to Spatial Navigation. Int J Mol Sci 2023; 24:ijms24054407. [PMID: 36901836 PMCID: PMC10002024 DOI: 10.3390/ijms24054407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Revised: 02/06/2023] [Accepted: 02/13/2023] [Indexed: 02/25/2023] Open
Abstract
Serotonin is a monoamine that acts in vertebrates and invertebrates as a modulator promoting changes in the structure and activity of brain areas relevant to animal behavior, ranging from sensory perception to learning and memory. Whether serotonin contributes in Drosophila to human-like cognitive abilities, including spatial navigation, is an issue little studied. Like in vertebrates, the serotonergic system in Drosophila is heterogeneous, meaning that distinct serotonergic neurons/circuits innervate specific fly brain regions to modulate precise behaviors. Here we review the literature that supports that serotonergic pathways modify different aspects underlying the formation of navigational memories in Drosophila.
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Affiliation(s)
- Ivana Gajardo
- Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago 8331150, Chile
- Departamento de Neurociencia, Instituto Milenio de Neurociencia Biomédica (BNI), Facultad de Medicina, Universidad de Chile, Santiago 8380453, Chile
| | - Simón Guerra
- Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago 8331150, Chile
| | - Jorge M. Campusano
- Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago 8331150, Chile
- Correspondence: ; Tel.: +56-2-2354-2133
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16
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Yan W, Lin H, Yu J, Wiggin TD, Wu L, Meng Z, Liu C, Griffith LC. Subtype-Specific Roles of Ellipsoid Body Ring Neurons in Sleep Regulation in Drosophila. J Neurosci 2023; 43:764-786. [PMID: 36535771 PMCID: PMC9899086 DOI: 10.1523/jneurosci.1350-22.2022] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2022] [Revised: 09/22/2022] [Accepted: 10/26/2022] [Indexed: 12/23/2022] Open
Abstract
The ellipsoid body (EB) is a major structure of the central complex of the Drosophila melanogaster brain. Twenty-two subtypes of EB ring neurons have been identified based on anatomic and morphologic characteristics by light-level microscopy and EM connectomics. A few studies have associated ring neurons with the regulation of sleep homeostasis and structure. However, cell type-specific and population interactions in the regulation of sleep remain unclear. Using an unbiased thermogenetic screen of EB drivers using female flies, we found the following: (1) multiple ring neurons are involved in the modulation of amount of sleep and structure in a synergistic manner; (2) analysis of data for ΔP(doze)/ΔP(wake) using a mixed Gaussian model detected 5 clusters of GAL4 drivers which had similar effects on sleep pressure and/or depth: lines driving arousal contained R4m neurons, whereas lines that increased sleep pressure had R3m cells; (3) a GLM analysis correlating ring cell subtype and activity-dependent changes in sleep parameters across all lines identified several cell types significantly associated with specific sleep effects: R3p was daytime sleep-promoting, and R4m was nighttime wake-promoting; and (4) R3d cells present in 5HT7-GAL4 and in GAL4 lines, which exclusively affect sleep structure, were found to contribute to fragmentation of sleep during both day and night. Thus, multiple subtypes of ring neurons distinctively control sleep amount and/or structure. The unique highly interconnected structure of the EB suggests a local-network model worth future investigation; understanding EB subtype interactions may provide insight how sleep circuits in general are structured.SIGNIFICANCE STATEMENT How multiple brain regions, with many cell types, can coherently regulate sleep remains unclear, but identification of cell type-specific roles can generate opportunities for understanding the principles of integration and cooperation. The ellipsoid body (EB) of the fly brain exhibits a high level of connectivity and functional heterogeneity yet is able to tune multiple behaviors in real-time, including sleep. Leveraging the powerful genetic tools available in Drosophila and recent progress in the characterization of the morphology and connectivity of EB ring neurons, we identify several EB subtypes specifically associated with distinct aspects of sleep. Our findings will aid in revealing the rules of coding and integration in the brain.
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Affiliation(s)
- Wei Yan
- Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, 518000, China
| | - Hai Lin
- Central Research Institute, United Imaging Healthcare, Shanghai, 200032, China
| | - Junwei Yu
- Department of Biology, National Center for Behavioral Genomics and Volen Center for Complex Systems, Brandeis University, Waltham, Massachusetts 02453
| | - Timothy D Wiggin
- Department of Biology, National Center for Behavioral Genomics and Volen Center for Complex Systems, Brandeis University, Waltham, Massachusetts 02453
| | - Litao Wu
- Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, 518000, China
| | - Zhiqiang Meng
- Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, 518000, China
- CAS Key Laboratory of Brain Connectome and Manipulation, Shenzhen, 518000, China
- Shenzhen Key Laboratory of Drug Addiction, Shenzhen, 518000, China
| | - Chang Liu
- Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, 518000, China
- CAS Key Laboratory of Brain Connectome and Manipulation, Shenzhen, 518000, China
- Shenzhen Key Laboratory of Viral Vectors for Biomedicine, Shenzhen, 518000, China
| | - Leslie C Griffith
- Department of Biology, National Center for Behavioral Genomics and Volen Center for Complex Systems, Brandeis University, Waltham, Massachusetts 02453
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17
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The sky compass network in the brain of the desert locust. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2022:10.1007/s00359-022-01601-x. [PMID: 36550368 DOI: 10.1007/s00359-022-01601-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 11/24/2022] [Accepted: 12/06/2022] [Indexed: 12/24/2022]
Abstract
Many arthropods and vertebrates use celestial signals such as the position of the sun during the day or stars at night as compass cues for spatial orientation. The neural network underlying sky compass coding in the brain has been studied in great detail in the desert locust Schistocerca gregaria. These insects perform long-range migrations in Northern Africa and the Middle East following seasonal changes in rainfall. Highly specialized photoreceptors in a dorsal rim area of their compound eyes are sensitive to the polarization of the sky, generated by scattered sunlight. These signals are combined with direct information on the sun position in the optic lobe and anterior optic tubercle and converge from both eyes in a midline crossing brain structure, the central complex. Here, head direction coding is achieved by a compass-like arrangement of columns signaling solar azimuth through a 360° range of space by combining direct brightness cues from the sun with polarization cues matching the polarization pattern of the sky. Other directional cues derived from wind direction and internal self-rotation input are likely integrated. Signals are transmitted as coherent steering commands to descending neurons for directional control of locomotion and flight.
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18
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Fisher YE, Marquis M, D'Alessandro I, Wilson RI. Dopamine promotes head direction plasticity during orienting movements. Nature 2022; 612:316-322. [PMID: 36450986 PMCID: PMC9729112 DOI: 10.1038/s41586-022-05485-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2022] [Accepted: 10/25/2022] [Indexed: 12/05/2022]
Abstract
In neural networks that store information in their connection weights, there is a tradeoff between sensitivity and stability1,2. Connections must be plastic to incorporate new information, but if they are too plastic, stored information can be corrupted. A potential solution is to allow plasticity only during epochs when task-specific information is rich, on the basis of a 'when-to-learn' signal3. We reasoned that dopamine provides a when-to-learn signal that allows the brain's spatial maps to update when new spatial information is available-that is, when an animal is moving. Here we show that the dopamine neurons innervating the Drosophila head direction network are specifically active when the fly turns to change its head direction. Moreover, their activity scales with moment-to-moment fluctuations in rotational speed. Pairing dopamine release with a visual cue persistently strengthens the cue's influence on head direction cells. Conversely, inhibiting these dopamine neurons decreases the influence of the cue. This mechanism should accelerate learning during moments when orienting movements are providing a rich stream of head direction information, allowing learning rates to be low at other times to protect stored information. Our results show how spatial learning in the brain can be compressed into discrete epochs in which high learning rates are matched to high rates of information intake.
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Affiliation(s)
- Yvette E Fisher
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
- Department of Molecular and Cellular Biology, University of California Berkeley, Berkeley, CA, USA
- Chan Zuckerberg Biohub, San Francisco, CA, USA
| | - Michael Marquis
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
| | | | - Rachel I Wilson
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA.
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19
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Lipophorin receptors regulate mushroom body development and complex behaviors in Drosophila. BMC Biol 2022; 20:198. [PMID: 36071487 PMCID: PMC9454125 DOI: 10.1186/s12915-022-01393-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Accepted: 08/17/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Drosophila melanogaster lipophorin receptors (LpRs), LpR1 and LpR2, are members of the LDLR family known to mediate lipid uptake in a range of organisms from Drosophila to humans. The vertebrate orthologs of LpRs, ApoER2 and VLDL-R, function as receptors of a glycoprotein involved in development of the central nervous system, Reelin, which is not present in flies. ApoER2 and VLDL-R are associated with the development and function of the hippocampus and cerebral cortex, important association areas in the mammalian brain, as well as with neurodevelopmental and neurodegenerative disorders linked to those regions. It is currently unknown whether LpRs play similar roles in the Drosophila brain. RESULTS We report that LpR-deficient flies exhibit impaired olfactory memory and sleep patterns, which seem to reflect anatomical defects found in a critical brain association area, the mushroom bodies (MB). Moreover, cultured MB neurons respond to mammalian Reelin by increasing the complexity of their neurite arborization. This effect depends on LpRs and Dab, the Drosophila ortholog of the Reelin signaling adaptor protein Dab1. In vitro, two of the long isoforms of LpRs allow the internalization of Reelin, suggesting that Drosophila LpRs interact with human Reelin to induce downstream cellular events. CONCLUSIONS These findings demonstrate that LpRs contribute to MB development and function, supporting the existence of a LpR-dependent signaling in Drosophila, and advance our understanding of the molecular factors functioning in neural systems to generate complex behaviors in this model. Our results further emphasize the importance of Drosophila as a model to investigate the alterations in specific genes contributing to neural disorders.
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20
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Farnworth MS, Bucher G, Hartenstein V. An atlas of the developing Tribolium castaneum brain reveals conservation in anatomy and divergence in timing to Drosophila melanogaster. J Comp Neurol 2022; 530:2335-2371. [PMID: 35535818 PMCID: PMC9646932 DOI: 10.1002/cne.25335] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 04/12/2022] [Accepted: 04/13/2022] [Indexed: 11/11/2022]
Abstract
Insect brains are formed by conserved sets of neural lineages whose fibers form cohesive bundles with characteristic projection patterns. Within the brain neuropil, these bundles establish a system of fascicles constituting the macrocircuitry of the brain. The overall architecture of the neuropils and the macrocircuitry appear to be conserved. However, variation is observed, for example, in size, shape, and timing of development. Unfortunately, the developmental and genetic basis of this variation is poorly understood, although the rise of new genetically tractable model organisms such as the red flour beetle Tribolium castaneum allows the possibility to gain mechanistic insights. To facilitate such work, we present an atlas of the developing brain of T. castaneum, covering the first larval instar, the prepupal stage, and the adult, by combining wholemount immunohistochemical labeling of fiber bundles (acetylated tubulin) and neuropils (synapsin) with digital 3D reconstruction using the TrakEM2 software package. Upon comparing this anatomical dataset with the published work in Drosophila melanogaster, we confirm an overall high degree of conservation. Fiber tracts and neuropil fascicles, which can be visualized by global neuronal antibodies like antiacetylated tubulin in all invertebrate brains, create a rich anatomical framework to which individual neurons or other regions of interest can be referred to. The framework of a largely conserved pattern allowed us to describe differences between the two species with respect to parameters such as timing of neuron proliferation and maturation. These features likely reflect adaptive changes in developmental timing that govern the change from larval to adult brain.
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Affiliation(s)
- Max S Farnworth
- Department of Evolutionary Developmental Genetics, Johann-Friedrich-Blumenbach Institute, GZMB, University of Göttingen, Göttingen, Germany
- Evolution of Brains and Behaviour lab, School of Biological Sciences, University of Bristol, Bristol, UK
| | - Gregor Bucher
- Department of Evolutionary Developmental Genetics, Johann-Friedrich-Blumenbach Institute, GZMB, University of Göttingen, Göttingen, Germany
| | - Volker Hartenstein
- Department of Molecular Cell and Developmental Biology, University of California/Los Angeles, Los Angeles, USA
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21
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Palavicino-Maggio CB, Sengupta S. The Neuromodulatory Basis of Aggression: Lessons From the Humble Fruit Fly. Front Behav Neurosci 2022; 16:836666. [PMID: 35517573 PMCID: PMC9062135 DOI: 10.3389/fnbeh.2022.836666] [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: 12/15/2021] [Accepted: 03/07/2022] [Indexed: 11/22/2022] Open
Abstract
Aggression is an intrinsic trait that organisms of almost all species, humans included, use to get access to food, shelter, and mating partners. To maximize fitness in the wild, an organism must vary the intensity of aggression toward the same or different stimuli. How much of this variation is genetic and how much is externally induced, is largely unknown but is likely to be a combination of both. Irrespective of the source, one of the principal physiological mechanisms altering the aggression intensity involves neuromodulation. Any change or variation in aggression intensity is most likely governed by a complex interaction of several neuromodulators acting via a meshwork of neural circuits. Resolving aggression-specific neural circuits in a mammalian model has proven challenging due to the highly complex nature of the mammalian brain. In that regard, the fruit fly model Drosophila melanogaster has provided insights into the circuit-driven mechanisms of aggression regulation and its underlying neuromodulatory basis. Despite morphological dissimilarities, the fly brain shares striking similarities with the mammalian brain in genes, neuromodulatory systems, and circuit-organization, making the findings from the fly model extremely valuable for understanding the fundamental circuit logic of human aggression. This review discusses our current understanding of how neuromodulators regulate aggression based on findings from the fruit fly model. We specifically focus on the roles of Serotonin (5-HT), Dopamine (DA), Octopamine (OA), Acetylcholine (ACTH), Sex Peptides (SP), Tachykinin (TK), Neuropeptide F (NPF), and Drosulfakinin (Dsk) in fruit fly male and female aggression.
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Affiliation(s)
- Caroline B Palavicino-Maggio
- Basic Neuroscience Division, Department of Psychiatry, Harvard Medical School, McLean Hospital, Boston, MA, United States.,Department of Neurobiology, Harvard Medical School, Boston, MA, United States
| | - Saheli Sengupta
- Basic Neuroscience Division, Department of Psychiatry, Harvard Medical School, McLean Hospital, Boston, MA, United States
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22
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Frighetto G, Zordan MA, Castiello U, Megighian A, Martin JR. Dopamine Modulation of Drosophila Ellipsoid Body Neurons, a Nod to the Mammalian Basal Ganglia. Front Physiol 2022; 13:849142. [PMID: 35492587 PMCID: PMC9048027 DOI: 10.3389/fphys.2022.849142] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Accepted: 03/10/2022] [Indexed: 12/04/2022] Open
Abstract
The central complex (CX) is a neural structure located on the midline of the insect brain that has been widely studied in the last few years. Its role in navigation and goal-oriented behaviors resembles those played by the basal ganglia in mammals. However, the neural mechanisms and the neurotransmitters involved in these processes remain unclear. Here, we exploited an in vivo bioluminescence Ca2+ imaging technique to record the activity in targeted neurons of the ellipsoid body (EB). We used different drugs to evoke excitatory Ca2+-responses, depending on the putative neurotransmitter released by their presynaptic inputs, while concomitant dopamine administration was employed to modulate those excitations. By using a genetic approach to knockdown the dopamine 1-like receptors, we showed that different dopamine modulatory effects are likely due to specific receptors expressed by the targeted population of neurons. Altogether, these results provide new data concerning how dopamine modulates and shapes the response of the ellipsoid body neurons. Moreover, they provide important insights regarding the similitude with mammals as far as the role played by dopamine in increasing and stabilizing the response of goal-related information.
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Affiliation(s)
- Giovanni Frighetto
- Department of General Psychology, University of Padova, Padova, Italy
- Institut des Neurosciences Paris-Saclay, Université Paris-Saclay, CNRS, Saclay, France
| | - Mauro A. Zordan
- Department of Biology, University of Padova, Padova, Italy
- Padova Neuroscience Center, University of Padova, Padova, Italy
| | - Umberto Castiello
- Department of General Psychology, University of Padova, Padova, Italy
| | - Aram Megighian
- Padova Neuroscience Center, University of Padova, Padova, Italy
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Jean-René Martin
- Institut des Neurosciences Paris-Saclay, Université Paris-Saclay, CNRS, Saclay, France
- *Correspondence: Jean-René Martin,
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23
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Flexible navigational computations in the Drosophila central complex. Curr Opin Neurobiol 2022; 73:102514. [DOI: 10.1016/j.conb.2021.12.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 12/12/2021] [Accepted: 12/22/2021] [Indexed: 12/25/2022]
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24
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Karam CS, Williams BL, Jones SK, Javitch JA. The Role of the Dopamine Transporter in the Effects of Amphetamine on Sleep and Sleep Architecture in Drosophila. Neurochem Res 2022; 47:177-189. [PMID: 33630236 PMCID: PMC8384956 DOI: 10.1007/s11064-021-03275-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Revised: 01/12/2021] [Accepted: 02/10/2021] [Indexed: 12/26/2022]
Abstract
The dopamine transporter (DAT) mediates the inactivation of released dopamine (DA) through its reuptake, and thereby plays an important homeostatic role in dopaminergic neurotransmission. Amphetamines exert their stimulant effects by targeting DAT and inducing the reverse transport of DA, leading to a dramatic increase of extracellular DA. Animal models have proven critical to investigating the molecular and cellular mechanisms underlying transporter function and its modulation by psychostimulants such as amphetamine. Here we establish a behavioral model for amphetamine action using adult Drosophila melanogaster. We use it to characterize the effects of amphetamine on sleep and sleep architecture. Our data show that amphetamine induces hyperactivity and disrupts sleep in a DA-dependent manner. Flies that do not express a functional DAT (dDAT null mutants) have been shown to be hyperactive and to exhibit significantly reduced sleep at baseline. Our data show that, in contrast to its action in control flies, amphetamine decreases the locomotor activity of dDAT null mutants and restores their sleep by modulating distinct aspects of sleep structure. To begin to explore the circuitry involved in the actions of amphetamine on sleep, we also describe the localization of dDAT throughout the fly brain, particularly in neuropils known to regulate sleep. Together, our data establish Drosophila as a robust model for studying the regulatory mechanisms that govern DAT function and psychostimulant action.
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Affiliation(s)
- Caline S Karam
- Department of Psychiatry, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
- Division of Molecular Therapeutics, New York State Psychiatric Institute, New York, NY, USA
| | - Brenna L Williams
- Division of Molecular Therapeutics, New York State Psychiatric Institute, New York, NY, USA
| | - Sandra K Jones
- Department of Psychiatry, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
- Division of Molecular Therapeutics, New York State Psychiatric Institute, New York, NY, USA
| | - Jonathan A Javitch
- Department of Psychiatry, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA.
- Division of Molecular Therapeutics, New York State Psychiatric Institute, New York, NY, USA.
- Department of Pharmacology, Columbia University Vagelos College of Physicians and Surgeons, 1051 Riverside Dr, Unit 19, New York, NY, 10032, USA.
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25
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Klöppel C, Hildebrandt K, Kolb D, Fürst N, Bley I, Karlowatz RJ, Walldorf U. Functional analysis of enhancer elements regulating the expression of the Drosophila homeodomain transcription factor DRx by gene targeting. Hereditas 2021; 158:42. [PMID: 34736520 PMCID: PMC8569992 DOI: 10.1186/s41065-021-00210-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Accepted: 10/18/2021] [Indexed: 11/17/2022] Open
Abstract
Background The Drosophila brain is an ideal model system to study stem cells, here called neuroblasts, and the generation of neural lineages. Many transcriptional activators are involved in formation of the brain during the development of Drosophila melanogaster. The transcription factor Drosophila Retinal homeobox (DRx), a member of the 57B homeobox gene cluster, is also one of these factors for brain development. Results In this study a detailed expression analysis of DRx in different developmental stages was conducted. We show that DRx is expressed in the embryonic brain in the protocerebrum, in the larval brain in the DM and DL lineages, the medulla and the lobula complex and in the central complex of the adult brain. We generated a DRx enhancer trap strain by gene targeting and reintegration of Gal4, which mimics the endogenous expression of DRx. With the help of eight existing enhancer-Gal4 strains and one made by our group, we mapped various enhancers necessary for the expression of DRx during all stages of brain development from the embryo to the adult. We made an analysis of some larger enhancer regions by gene targeting. Deletion of three of these enhancers showing the most prominent expression patterns in the brain resulted in specific temporal and spatial loss of DRx expression in defined brain structures. Conclusion Our data show that DRx is expressed in specific neuroblasts and defined neural lineages and suggest that DRx is another important factor for Drosophila brain development. Supplementary Information The online version contains supplementary material available at 10.1186/s41065-021-00210-z.
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Affiliation(s)
- Christine Klöppel
- Developmental Biology, Saarland University, Building 61, 66421, Homburg/Saar, Germany
| | - Kirsten Hildebrandt
- Developmental Biology, Saarland University, Building 61, 66421, Homburg/Saar, Germany
| | - Dieter Kolb
- Developmental Biology, Saarland University, Building 61, 66421, Homburg/Saar, Germany
| | - Nora Fürst
- Developmental Biology, Saarland University, Building 61, 66421, Homburg/Saar, Germany.,Present address: Genetics/Epigenetics, Saarland University, Building A2.4, 66123, Saarbrücken, Germany
| | - Isabelle Bley
- Developmental Biology, Saarland University, Building 61, 66421, Homburg/Saar, Germany.,Present address: Research Institute Children's Cancer Center Hamburg, Building N63, Martinistr. 52, 20251, Hamburg, Germany
| | | | - Uwe Walldorf
- Developmental Biology, Saarland University, Building 61, 66421, Homburg/Saar, Germany.
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26
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Drosophila ß Heavy-Spectrin is required in polarized ensheathing glia that form a diffusion-barrier around the neuropil. Nat Commun 2021; 12:6357. [PMID: 34737284 PMCID: PMC8569210 DOI: 10.1038/s41467-021-26462-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Accepted: 10/06/2021] [Indexed: 01/03/2023] Open
Abstract
In the central nervous system (CNS), functional tasks are often allocated to distinct compartments. This is also evident in the Drosophila CNS where synapses and dendrites are clustered in distinct neuropil regions. The neuropil is separated from neuronal cell bodies by ensheathing glia, which as we show using dye injection experiments, contribute to the formation of an internal diffusion barrier. We find that ensheathing glia are polarized with a basolateral plasma membrane rich in phosphatidylinositol-(3,4,5)-triphosphate (PIP3) and the Na+/K+-ATPase Nervana2 (Nrv2) that abuts an extracellular matrix formed at neuropil-cortex interface. The apical plasma membrane is facing the neuropil and is rich in phosphatidylinositol-(4,5)-bisphosphate (PIP2) that is supported by a sub-membranous ßHeavy-Spectrin cytoskeleton. ßHeavy-spectrin mutant larvae affect ensheathing glial cell polarity with delocalized PIP2 and Nrv2 and exhibit an abnormal locomotion which is similarly shown by ensheathing glia ablated larvae. Thus, polarized glia compartmentalizes the brain and is essential for proper nervous system function.
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27
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Hulse BK, Haberkern H, Franconville R, Turner-Evans D, Takemura SY, Wolff T, Noorman M, Dreher M, Dan C, Parekh R, Hermundstad AM, Rubin GM, Jayaraman V. A connectome of the Drosophila central complex reveals network motifs suitable for flexible navigation and context-dependent action selection. eLife 2021; 10:e66039. [PMID: 34696823 PMCID: PMC9477501 DOI: 10.7554/elife.66039] [Citation(s) in RCA: 122] [Impact Index Per Article: 40.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Accepted: 09/07/2021] [Indexed: 11/13/2022] Open
Abstract
Flexible behaviors over long timescales are thought to engage recurrent neural networks in deep brain regions, which are experimentally challenging to study. In insects, recurrent circuit dynamics in a brain region called the central complex (CX) enable directed locomotion, sleep, and context- and experience-dependent spatial navigation. We describe the first complete electron microscopy-based connectome of the Drosophila CX, including all its neurons and circuits at synaptic resolution. We identified new CX neuron types, novel sensory and motor pathways, and network motifs that likely enable the CX to extract the fly's head direction, maintain it with attractor dynamics, and combine it with other sensorimotor information to perform vector-based navigational computations. We also identified numerous pathways that may facilitate the selection of CX-driven behavioral patterns by context and internal state. The CX connectome provides a comprehensive blueprint necessary for a detailed understanding of network dynamics underlying sleep, flexible navigation, and state-dependent action selection.
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Affiliation(s)
- Brad K Hulse
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Hannah Haberkern
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Romain Franconville
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Daniel Turner-Evans
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Shin-ya Takemura
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Tanya Wolff
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Marcella Noorman
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Marisa Dreher
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Chuntao Dan
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Ruchi Parekh
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Ann M Hermundstad
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Gerald M Rubin
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Vivek Jayaraman
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
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28
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Plasticity between visual input pathways and the head direction system. Curr Opin Neurobiol 2021; 71:60-68. [PMID: 34619578 DOI: 10.1016/j.conb.2021.08.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2021] [Accepted: 08/26/2021] [Indexed: 11/21/2022]
Abstract
Animals can maintain a stable sense of direction even when they navigate in novel environments, but how the animal's brain interprets and encodes unfamiliar sensory information in its navigation system to maintain a stable sense of direction is a mystery. Recent studies have suggested that distinct brain structures of mammals and insects have evolved to solve this common problem with strategies that share computational principles; specifically, a network structure called a ring attractor maintains the sense of direction. Initially, in a novel environment, the animal's sense of direction relies on self-motion cues. Over time, the mapping from visual inputs to head direction cells, responsible for the sense of direction, is established via experience-dependent plasticity. Yet the mechanisms that facilitate acquiring a world-centered sense of direction, how many environments can be stored in memory, and what visual features are selected, all remain unknown. Thanks to recent advances in large scale physiological recording, genetic tools, and theory, these mechanisms may soon be revealed.
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29
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Hensgen R, Göthe J, Jahn S, Hümmert S, Schneider KL, Takahashi N, Pegel U, Gotthardt S, Homberg U. Organization and neural connections of the lateral complex in the brain of the desert locust. J Comp Neurol 2021; 529:3533-3560. [PMID: 34216020 DOI: 10.1002/cne.25209] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 06/24/2021] [Accepted: 06/28/2021] [Indexed: 11/08/2022]
Abstract
The lateral complexes (LXs) are bilaterally paired neuropils in the insect brain that mediate communication between the central complex (CX), a brain center controlling spatial orientation, various sensory processing areas, and thoracic motor centers that execute locomotion. The LX of the desert locust consists of the lateral accessory lobe (LAL), and the medial and lateral bulb. We have analyzed the anatomical organization and the neuronal connections of the LX in the locust, to provide a basis for future functional studies. Reanalyzing the morphology of neurons connecting the CX and the LX revealed likely feedback loops in the sky compass network of the CX via connections in the gall of the LAL and a newly identified neuropil termed ovoid body. In addition, we characterized 16 different types of neuron that connect the LAL with other areas in the brain. Eight types of neuron provide information flow between both LALs, five types are LAL input neurons, and three types are LAL output neurons. Among these are neurons providing input from sensory brain areas such as the lobula and antennal neuropils. Brain regions most often targeted by LAL neurons are the posterior slope, the wedge, and the crepine. Two descending neurons with dendrites in the LAL were identified. Our data support and complement existing knowledge about how the LAL is embedded in the neuronal network involved in processing of sensory information and generation of appropriate behavioral output for goal-directed locomotion.
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Affiliation(s)
- Ronja Hensgen
- Department of Biology, Animal Physiology, Philipps-Universität Marburg, Marburg, Germany
| | - Jonas Göthe
- Department of Biology, Animal Physiology, Philipps-Universität Marburg, Marburg, Germany
| | - Stefanie Jahn
- Department of Biology, Animal Physiology, Philipps-Universität Marburg, Marburg, Germany
| | - Sophie Hümmert
- Department of Biology, Animal Physiology, Philipps-Universität Marburg, Marburg, Germany
| | - Kim Lucia Schneider
- Department of Biology, Animal Physiology, Philipps-Universität Marburg, Marburg, Germany
| | - Naomi Takahashi
- Department of Biology, Animal Physiology, Philipps-Universität Marburg, Marburg, Germany
| | - Uta Pegel
- Department of Biology, Animal Physiology, Philipps-Universität Marburg, Marburg, Germany
| | - Sascha Gotthardt
- Department of Biology, Animal Physiology, Philipps-Universität Marburg, Marburg, Germany
| | - Uwe Homberg
- Department of Biology, Animal Physiology, Philipps-Universität Marburg, Marburg, Germany.,Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus Liebig University Giessen, Marburg, Germany
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30
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Flores-Valle A, Gonçalves PJ, Seelig JD. Integration of sleep homeostasis and navigation in Drosophila. PLoS Comput Biol 2021; 17:e1009088. [PMID: 34252086 PMCID: PMC8297946 DOI: 10.1371/journal.pcbi.1009088] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 07/22/2021] [Accepted: 05/17/2021] [Indexed: 11/25/2022] Open
Abstract
During sleep, the brain undergoes dynamic and structural changes. In Drosophila, such changes have been observed in the central complex, a brain area important for sleep control and navigation. The connectivity of the central complex raises the question about how navigation, and specifically the head direction system, can operate in the face of sleep related plasticity. To address this question, we develop a model that integrates sleep homeostasis and head direction. We show that by introducing plasticity, the head direction system can function in a stable way by balancing plasticity in connected circuits that encode sleep pressure. With increasing sleep pressure, the head direction system nevertheless becomes unstable and a sleep phase with a different plasticity mechanism is introduced to reset network connectivity. The proposed integration of sleep homeostasis and head direction circuits captures features of their neural dynamics observed in flies and mice.
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Affiliation(s)
- Andres Flores-Valle
- Center of Advanced European Studies and Research (caesar), Bonn, Germany
- International Max Planck Research School for Brain and Behavior, Bonn, Germany
| | - Pedro J. Gonçalves
- Max Planck Research Group Neural Systems Analysis, Center of Advanced European Studies and Research (caesar), Bonn, Germany
- Computational Neuroengineering, Department of Electrical and Computer Engineering, Technical University of Munich, Munich, Germany
| | - Johannes D. Seelig
- Center of Advanced European Studies and Research (caesar), Bonn, Germany
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31
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Timm J, Scherner M, Matschke J, Kern M, Homberg U. Tyrosine hydroxylase immunostaining in the central complex of dicondylian insects. J Comp Neurol 2021; 529:3131-3154. [PMID: 33825188 DOI: 10.1002/cne.25151] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 03/31/2021] [Accepted: 04/01/2021] [Indexed: 12/20/2022]
Abstract
Dopamine acts as a neurohormone and neurotransmitter in the insect nervous system and controls a variety of physiological processes. Dopaminergic neurons also innervate the central complex (CX), a multisensory center of the insect brain involved in sky compass navigation, goal-directed locomotion and sleep control. To infer a possible influence of evolutionary history and lifestyle on the neurochemical architecture of the CX, we have studied the distribution of neurons immunoreactive to tyrosine hydroxylase (TH), the rate-limiting enzyme in dopamine biosynthesis. Analysis of representatives from 12 insect orders ranging from firebrats to flies revealed high conservation of immunolabeled neurons. One type of TH-immunoreactive neuron was found in all species studied. The neurons have somata in the pars intercerebralis, arborizations in the lateral accessory lobes, and axonal ramifications in the central body and noduli. In all pterygote species, a second type of tangential neuron of the upper division of the central body was TH-immunoreactive. The neurons have cell bodies near the calyces and arborizations in the superior protocerebrum. Both types of neuron showed species-specific variations in cell number and in the innervated areas outside and inside the CX. Additional neurons were found in only two taxa: one type of columnar neuron showed TH immunostaining in the water strider Gerris lacustris, but not in other Heteroptera, and a tritocerebral neuron innervating the protocerebral bridge was immunolabeled in Diptera. The data show largely taxon-specific variations of a common ground pattern of putatively dopaminergic neurons that may be commonly involved in state-dependent modulation of CX function.
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Affiliation(s)
- Josephine Timm
- Department of Biology, Animal Physiology, Philipps-Universität Marburg, Marburg, Germany
| | - Mara Scherner
- Department of Biology, Animal Physiology, Philipps-Universität Marburg, Marburg, Germany
| | - Jannik Matschke
- Department of Biology, Animal Physiology, Philipps-Universität Marburg, Marburg, Germany
| | - Martina Kern
- Department of Biology, Animal Physiology, Philipps-Universität Marburg, Marburg, Germany
| | - Uwe Homberg
- Department of Biology, Animal Physiology, Philipps-Universität Marburg, Marburg, Germany.,Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus Liebig University Giessen, Giessen, Germany
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32
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Luo Y, Johnson JC, Chakraborty TS, Piontkowski A, Gendron CM, Pletcher SD. Yeast volatiles double starvation survival in Drosophila. SCIENCE ADVANCES 2021; 7:eabf8896. [PMID: 33980491 PMCID: PMC8115925 DOI: 10.1126/sciadv.abf8896] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Accepted: 03/23/2021] [Indexed: 06/12/2023]
Abstract
Organisms make decisions based on the information they gather from their environment, the effects of which affect their fitness. Understanding how these interactions affect physiology may generate interventions that improve the length and quality of life. Here, we provide evidence that exposure to live yeast volatiles during starvation significantly extends survival, increases activity, and slows the rate of triacylglyceride (TAG) decline independent of canonical sensory perception. We demonstrate that ethanol (EtOH) is one of the active components in yeast volatiles that influences these phenotypes and that EtOH metabolites mediate dynamic mechanisms to promote Drosophila survival. Silencing R4d neurons reverses the ability of high EtOH concentrations to promote starvation survival, and their activation promotes EtOH metabolism. The transcription factor foxo promotes EtOH resistance, likely by protection from EtOH toxicity. Our results suggest that food-related cues recruit neural circuits and modulate stress signaling pathways to promote survival during starvation.
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Affiliation(s)
- Yuan Luo
- Department of Molecular and Integrative Physiology and the Geriatrics Center, University of Michigan, Ann Arbor, MI, USA
| | - Jacob C Johnson
- Department of Molecular and Integrative Physiology and the Geriatrics Center, University of Michigan, Ann Arbor, MI, USA
| | - Tuhin S Chakraborty
- Department of Molecular and Integrative Physiology and the Geriatrics Center, University of Michigan, Ann Arbor, MI, USA
| | - Austin Piontkowski
- Department of Molecular and Integrative Physiology and the Geriatrics Center, University of Michigan, Ann Arbor, MI, USA
| | - Christi M Gendron
- Department of Molecular and Integrative Physiology and the Geriatrics Center, University of Michigan, Ann Arbor, MI, USA
| | - Scott D Pletcher
- Department of Molecular and Integrative Physiology and the Geriatrics Center, University of Michigan, Ann Arbor, MI, USA.
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33
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Ishimoto H, Kamikouchi A. Molecular and neural mechanisms regulating sexual motivation of virgin female Drosophila. Cell Mol Life Sci 2021; 78:4805-4819. [PMID: 33837450 PMCID: PMC11071752 DOI: 10.1007/s00018-021-03820-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Revised: 03/04/2021] [Accepted: 03/23/2021] [Indexed: 01/06/2023]
Abstract
During courtship, multiple information sources are integrated in the brain to reach a final decision, i.e., whether or not to mate. The brain functions for this complex behavior can be investigated by genetically manipulating genes and neurons, and performing anatomical, physiological, and behavioral analyses. Drosophila is a powerful model experimental system for such studies, which need to be integrated from molecular and cellular levels to the behavioral level, and has enabled pioneering research to be conducted. In male flies, which exhibit a variety of characteristic sexual behaviors, we have accumulated knowledge of many genes and neural circuits that control sexual behaviors. On the other hand, despite the importance of the mechanisms of mating decision-making in females from an evolutionary perspective (such as sexual selection), research on the mechanisms that control sexual behavior in females has progressed somewhat slower. In this review, we focus on the pre-mating behavior of female Drosophila melanogaster, and introduce previous key findings on the neuronal and molecular mechanisms that integrate sensory information and selective expression of behaviors toward the courting male.
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Grants
- JP20H03355 Ministry of Education, Culture, Sports, Science and Technology
- JP20H04997 Ministry of Education, Culture, Sports, Science and Technology
- 19H04933 Ministry of Education, Culture, Sports, Science and Technology
- 17K19450 Ministry of Education, Culture, Sports, Science and Technology
- 15K07147 Ministry of Education, Culture, Sports, Science and Technology
- 18K06332 Ministry of Education, Culture, Sports, Science and Technology
- Naito Foundation
- Inamori Foundation
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Affiliation(s)
- Hiroshi Ishimoto
- Graduate School of Science, Nagoya University, Nagoya, Aichi, 464-8602, Japan.
| | - Azusa Kamikouchi
- Graduate School of Science, Nagoya University, Nagoya, Aichi, 464-8602, Japan.
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34
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Hardcastle BJ, Omoto JJ, Kandimalla P, Nguyen BCM, Keleş MF, Boyd NK, Hartenstein V, Frye MA. A visual pathway for skylight polarization processing in Drosophila. eLife 2021; 10:e63225. [PMID: 33755020 PMCID: PMC8051946 DOI: 10.7554/elife.63225] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Accepted: 03/08/2021] [Indexed: 11/13/2022] Open
Abstract
Many insects use patterns of polarized light in the sky to orient and navigate. Here, we functionally characterize neural circuitry in the fruit fly, Drosophila melanogaster, that conveys polarized light signals from the eye to the central complex, a brain region essential for the fly's sense of direction. Neurons tuned to the angle of polarization of ultraviolet light are found throughout the anterior visual pathway, connecting the optic lobes with the central complex via the anterior optic tubercle and bulb, in a homologous organization to the 'sky compass' pathways described in other insects. We detail how a consistent, map-like organization of neural tunings in the peripheral visual system is transformed into a reduced representation suited to flexible processing in the central brain. This study identifies computational motifs of the transformation, enabling mechanistic comparisons of multisensory integration and central processing for navigation in the brains of insects.
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Affiliation(s)
- Ben J Hardcastle
- Department of Integrative Biology and Physiology, University of California, Los AngelesLos AngelesUnited States
| | - Jaison J Omoto
- Department of Molecular, Cell and Developmental Biology, University of California, Los AngelesLos AngelesUnited States
| | - Pratyush Kandimalla
- Department of Molecular, Cell and Developmental Biology, University of California, Los AngelesLos AngelesUnited States
| | - Bao-Chau M Nguyen
- Department of Molecular, Cell and Developmental Biology, University of California, Los AngelesLos AngelesUnited States
| | - Mehmet F Keleş
- Department of Integrative Biology and Physiology, University of California, Los AngelesLos AngelesUnited States
| | - Natalie K Boyd
- Department of Molecular, Cell and Developmental Biology, University of California, Los AngelesLos AngelesUnited States
| | - Volker Hartenstein
- Department of Molecular, Cell and Developmental Biology, University of California, Los AngelesLos AngelesUnited States
| | - Mark A Frye
- Department of Integrative Biology and Physiology, University of California, Los AngelesLos AngelesUnited States
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35
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Koch SC, Nelson A, Hartenstein V. Structural aspects of the aging invertebrate brain. Cell Tissue Res 2021; 383:931-947. [PMID: 33409654 PMCID: PMC7965346 DOI: 10.1007/s00441-020-03314-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 09/28/2020] [Indexed: 11/26/2022]
Abstract
Aging is characterized by a decline in neuronal function in all animal species investigated so far. Functional changes are accompanied by and may be in part caused by, structurally visible degenerative changes in neurons. In the mammalian brain, normal aging shows abnormalities in dendrites and axons, as well as ultrastructural changes in synapses, rather than global neuron loss. The analysis of the structural features of aging neurons, as well as their causal link to molecular mechanisms on the one hand, and the functional decline on the other hand is crucial in order to understand the aging process in the brain. Invertebrate model organisms like Drosophila and C. elegans offer the opportunity to apply a forward genetic approach to the analysis of aging. In the present review, we aim to summarize findings concerning abnormalities in morphology and ultrastructure in invertebrate brains during normal aging and compare them to what is known for the mammalian brain. It becomes clear that despite of their considerably shorter life span, invertebrates display several age-related changes very similar to the mammalian condition, including the retraction of dendritic and axonal branches at specific locations, changes in synaptic density and increased accumulation of presynaptic protein complexes. We anticipate that continued research efforts in invertebrate systems will significantly contribute to reveal (and possibly manipulate) the molecular/cellular pathways leading to neuronal aging in the mammalian brain.
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Affiliation(s)
- Sandra C Koch
- Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles (UCLA), Los Angeles, California, USA
| | - Annie Nelson
- Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles (UCLA), Los Angeles, California, USA
| | - Volker Hartenstein
- Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles (UCLA), Los Angeles, California, USA.
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36
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Buhl E, Kottler B, Hodge JJL, Hirth F. Thermoresponsive motor behavior is mediated by ring neuron circuits in the central complex of Drosophila. Sci Rep 2021; 11:155. [PMID: 33420240 PMCID: PMC7794218 DOI: 10.1038/s41598-020-80103-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 12/11/2020] [Indexed: 02/05/2023] Open
Abstract
Insects are ectothermal animals that are constrained in their survival and reproduction by external temperature fluctuations which require either active avoidance of or movement towards a given heat source. In Drosophila, different thermoreceptors and neurons have been identified that mediate temperature sensation to maintain the animal’s thermal preference. However, less is known how thermosensory information is integrated to gate thermoresponsive motor behavior. Here we use transsynaptic tracing together with calcium imaging, electrophysiology and thermogenetic manipulations in freely moving Drosophila exposed to elevated temperature and identify different functions of ellipsoid body ring neurons, R1-R4, in thermoresponsive motor behavior. Our results show that warming of the external surroundings elicits calcium influx specifically in R2-R4 but not in R1, which evokes threshold-dependent neural activity in the outer layer ring neurons. In contrast to R2, R3 and R4d neurons, thermogenetic inactivation of R4m and R1 neurons expressing the temperature-sensitive mutant allele of dynamin, shibireTS, results in impaired thermoresponsive motor behavior at elevated 31 °C. trans-Tango mediated transsynaptic tracing together with physiological and behavioral analyses indicate that integrated sensory information of warming is registered by neural activity of R4m as input layer of the ellipsoid body ring neuropil and relayed on to R1 output neurons that gate an adaptive motor response. Together these findings imply that segregated activities of central complex ring neurons mediate sensory-motor transformation of external temperature changes and gate thermoresponsive motor behavior in Drosophila.
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Affiliation(s)
- Edgar Buhl
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, University Walk, Bristol, UK.
| | - Benjamin Kottler
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - James J L Hodge
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, University Walk, Bristol, UK
| | - Frank Hirth
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK.
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37
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Ni L. Genetic Transsynaptic Techniques for Mapping Neural Circuits in Drosophila. Front Neural Circuits 2021; 15:749586. [PMID: 34675781 PMCID: PMC8524129 DOI: 10.3389/fncir.2021.749586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 09/13/2021] [Indexed: 11/23/2022] Open
Abstract
A neural circuit is composed of a population of neurons that are interconnected by synapses and carry out a specific function when activated. It is the structural framework for all brain functions. Its impairments often cause diseases in the nervous system. To understand computations and functions in a brain circuit, it is of crucial importance to identify how neurons in this circuit are connected. Genetic transsynaptic techniques provide opportunities to efficiently answer this question. These techniques label synapses or across synapses to unbiasedly label synaptic partners. They allow for mapping neural circuits with high reproducibility and throughput, as well as provide genetic access to synaptically connected neurons that enables visualization and manipulation of these neurons simultaneously. This review focuses on three recently developed Drosophila genetic transsynaptic tools for detecting chemical synapses, highlights their advantages and potential pitfalls, and discusses the future development needs of these techniques.
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38
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Cheong HS, Siwanowicz I, Card GM. Multi-regional circuits underlying visually guided decision-making in Drosophila. Curr Opin Neurobiol 2020; 65:77-87. [PMID: 33217639 DOI: 10.1016/j.conb.2020.10.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 09/30/2020] [Accepted: 10/02/2020] [Indexed: 12/26/2022]
Abstract
Visually guided decision-making requires integration of information from distributed brain areas, necessitating a brain-wide approach to examine its neural mechanisms. New tools in Drosophila melanogaster enable circuits spanning the brain to be charted with single cell-type resolution. Here, we highlight recent advances uncovering the computations and circuits that transform and integrate visual information across the brain to make behavioral choices. Visual information flows from the optic lobes to three primary central brain regions: a sensorimotor mapping area and two 'higher' centers for memory or spatial orientation. Rapid decision-making during predator evasion emerges from the spike timing dynamics in parallel sensorimotor cascades. Goal-directed decisions may occur through memory, navigation and valence processing in the central complex and mushroom bodies.
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Affiliation(s)
- Han Sj Cheong
- HHMI Janelia Research Campus, 19700 Helix Drive, Ashburn, VA 20147, United States
| | - Igor Siwanowicz
- HHMI Janelia Research Campus, 19700 Helix Drive, Ashburn, VA 20147, United States
| | - Gwyneth M Card
- HHMI Janelia Research Campus, 19700 Helix Drive, Ashburn, VA 20147, United States.
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39
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Homberg U, Hensgen R, Rieber E, Seyfarth J, Kern M, Dippel S, Dircksen H, Spänig L, Kina YP. Orcokinin in the central complex of the locust Schistocerca gregaria: Identification of immunostained neurons and colocalization with other neuroactive substances. J Comp Neurol 2020; 529:1876-1894. [PMID: 33128250 DOI: 10.1002/cne.25062] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 10/22/2020] [Accepted: 10/22/2020] [Indexed: 12/20/2022]
Abstract
The central complex is a group of highly interconnected neuropils in the insect brain. It is involved in the control of spatial orientation, based on external compass cues and various internal needs. The functional and neurochemical organization of the central complex has been studied in detail in the desert locust Schistocerca gregaria. In addition to classical neurotransmitters, immunocytochemistry has provided evidence for a major contribution of neuropeptides to neural signaling within the central complex. To complement these data, we have identified all orcokinin-immunoreactive neurons in the locust central complex and associated brain areas. About 50 bilateral pairs of neurons innervating all substructures of the central complex exhibit orcokinin immunoreactivity. Among these were about 20 columnar neurons, 33 bilateral pairs of tangential neurons of the central body, and seven pairs of tangential neurons of the protocerebral bridge. In silico transcript analysis suggests the presence of eight different orcokinin-A type peptides in the desert locust. Double label experiments showed that all orcokinin-immunostained tangential neurons of the lateral accessory lobe cluster were also immunoreactive for GABA and the GABA-synthesizing enzyme glutamic acid decarboxylase. Two types of tangential neurons of the upper division of the central body were, furthermore, also labeled with an antiserum against Dip-allatostatin I. No colocalization was found with serotonin immunostaining. The data provide additional insights into the neurochemical organization of the locust central complex and suggest that orcokinin-peptides of the orcokinin-A gene act as neuroactive substances at all stages of signal processing in this brain area.
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Affiliation(s)
- Uwe Homberg
- Department of Biology, Animal Physiology & Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus Liebig University Giessen, Marburg, Germany
| | - Ronja Hensgen
- Department of Biology, Animal Physiology & Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus Liebig University Giessen, Marburg, Germany
| | - Evelyn Rieber
- Department of Biology, Animal Physiology & Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus Liebig University Giessen, Marburg, Germany.,Behavioral Physiology and Sociobiology, Biocenter, University of Würzburg, Würzburg, Germany
| | - Jutta Seyfarth
- Department of Biology, Animal Physiology & Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus Liebig University Giessen, Marburg, Germany
| | - Martina Kern
- Department of Biology, Animal Physiology & Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus Liebig University Giessen, Marburg, Germany
| | - Stefan Dippel
- Department of Biology, Animal Physiology & Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus Liebig University Giessen, Marburg, Germany
| | | | - Lisa Spänig
- Department of Biology, Animal Physiology & Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus Liebig University Giessen, Marburg, Germany
| | - Yelda Pakize Kina
- Department of Biology, Animal Physiology & Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus Liebig University Giessen, Marburg, Germany
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40
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Turner-Evans DB, Jensen KT, Ali S, Paterson T, Sheridan A, Ray RP, Wolff T, Lauritzen JS, Rubin GM, Bock DD, Jayaraman V. The Neuroanatomical Ultrastructure and Function of a Biological Ring Attractor. Neuron 2020; 108:145-163.e10. [PMID: 32916090 PMCID: PMC8356802 DOI: 10.1016/j.neuron.2020.08.006] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 05/20/2020] [Accepted: 08/05/2020] [Indexed: 01/31/2023]
Abstract
Neural representations of head direction (HD) have been discovered in many species. Theoretical work has proposed that the dynamics associated with these representations are generated, maintained, and updated by recurrent network structures called ring attractors. We evaluated this theorized structure-function relationship by performing electron-microscopy-based circuit reconstruction and RNA profiling of identified cell types in the HD system of Drosophila melanogaster. We identified motifs that have been hypothesized to maintain the HD representation in darkness, update it when the animal turns, and tether it to visual cues. Functional studies provided support for the proposed roles of individual excitatory or inhibitory circuit elements in shaping activity. We also discovered recurrent connections between neuronal arbors with mixed pre- and postsynaptic specializations. Our results confirm that the Drosophila HD network contains the core components of a ring attractor while also revealing unpredicted structural features that might enhance the network's computational power.
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Affiliation(s)
| | - Kristopher T Jensen
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA; Computational and Biological Learning Lab, Department of Engineering, University of Cambridge, Cambridge, UK
| | - Saba Ali
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Tyler Paterson
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Arlo Sheridan
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Robert P Ray
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Tanya Wolff
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - J Scott Lauritzen
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Gerald M Rubin
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Davi D Bock
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA; Department of Neurological Sciences, Larner College of Medicine, University of Vermont, Burlington, VT 05405, USA
| | - Vivek Jayaraman
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA.
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41
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Okubo TS, Patella P, D'Alessandro I, Wilson RI. A Neural Network for Wind-Guided Compass Navigation. Neuron 2020; 107:924-940.e18. [PMID: 32681825 PMCID: PMC7507644 DOI: 10.1016/j.neuron.2020.06.022] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 05/13/2020] [Accepted: 06/22/2020] [Indexed: 11/27/2022]
Abstract
Spatial maps in the brain are most accurate when they are linked to external sensory cues. Here, we show that the compass in the Drosophila brain is linked to the direction of the wind. Shifting the wind rightward rotates the compass as if the fly were turning leftward, and vice versa. We describe the mechanisms of several computations that integrate wind information into the compass. First, an intensity-invariant representation of wind direction is computed by comparing left-right mechanosensory signals. Then, signals are reformatted to reduce the coding biases inherent in peripheral mechanics, and wind cues are brought into the same circular coordinate system that represents visual cues and self-motion signals. Because the compass incorporates both mechanosensory and visual cues, it should enable navigation under conditions where no single cue is consistently reliable. These results show how local sensory signals can be transformed into a global, multimodal, abstract representation of space.
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Affiliation(s)
- Tatsuo S Okubo
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
| | - Paola Patella
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
| | | | - Rachel I Wilson
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA.
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42
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Scheffer LK, Xu CS, Januszewski M, Lu Z, Takemura SY, Hayworth KJ, Huang GB, Shinomiya K, Maitlin-Shepard J, Berg S, Clements J, Hubbard PM, Katz WT, Umayam L, Zhao T, Ackerman D, Blakely T, Bogovic J, Dolafi T, Kainmueller D, Kawase T, Khairy KA, Leavitt L, Li PH, Lindsey L, Neubarth N, Olbris DJ, Otsuna H, Trautman ET, Ito M, Bates AS, Goldammer J, Wolff T, Svirskas R, Schlegel P, Neace E, Knecht CJ, Alvarado CX, Bailey DA, Ballinger S, Borycz JA, Canino BS, Cheatham N, Cook M, Dreher M, Duclos O, Eubanks B, Fairbanks K, Finley S, Forknall N, Francis A, Hopkins GP, Joyce EM, Kim S, Kirk NA, Kovalyak J, Lauchie SA, Lohff A, Maldonado C, Manley EA, McLin S, Mooney C, Ndama M, Ogundeyi O, Okeoma N, Ordish C, Padilla N, Patrick CM, Paterson T, Phillips EE, Phillips EM, Rampally N, Ribeiro C, Robertson MK, Rymer JT, Ryan SM, Sammons M, Scott AK, Scott AL, Shinomiya A, Smith C, Smith K, Smith NL, Sobeski MA, Suleiman A, Swift J, Takemura S, Talebi I, Tarnogorska D, Tenshaw E, Tokhi T, Walsh JJ, Yang T, Horne JA, Li F, Parekh R, Rivlin PK, Jayaraman V, Costa M, Jefferis GSXE, Ito K, Saalfeld S, George R, Meinertzhagen IA, Rubin GM, Hess HF, Jain V, Plaza SM. A connectome and analysis of the adult Drosophila central brain. eLife 2020; 9:e57443. [PMID: 32880371 PMCID: PMC7546738 DOI: 10.7554/elife.57443] [Citation(s) in RCA: 450] [Impact Index Per Article: 112.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 09/01/2020] [Indexed: 12/26/2022] Open
Abstract
The neural circuits responsible for animal behavior remain largely unknown. We summarize new methods and present the circuitry of a large fraction of the brain of the fruit fly Drosophila melanogaster. Improved methods include new procedures to prepare, image, align, segment, find synapses in, and proofread such large data sets. We define cell types, refine computational compartments, and provide an exhaustive atlas of cell examples and types, many of them novel. We provide detailed circuits consisting of neurons and their chemical synapses for most of the central brain. We make the data public and simplify access, reducing the effort needed to answer circuit questions, and provide procedures linking the neurons defined by our analysis with genetic reagents. Biologically, we examine distributions of connection strengths, neural motifs on different scales, electrical consequences of compartmentalization, and evidence that maximizing packing density is an important criterion in the evolution of the fly's brain.
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Affiliation(s)
- Louis K Scheffer
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - C Shan Xu
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | | | - Zhiyuan Lu
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
- Life Sciences Centre, Dalhousie UniversityHalifaxCanada
| | - Shin-ya Takemura
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Kenneth J Hayworth
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Gary B Huang
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Kazunori Shinomiya
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | | | - Stuart Berg
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Jody Clements
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Philip M Hubbard
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - William T Katz
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Lowell Umayam
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Ting Zhao
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - David Ackerman
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | | | - John Bogovic
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Tom Dolafi
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Dagmar Kainmueller
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Takashi Kawase
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Khaled A Khairy
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | | | - Peter H Li
- Google ResearchMountain ViewUnited States
| | | | - Nicole Neubarth
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Donald J Olbris
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Hideo Otsuna
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Eric T Trautman
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Masayoshi Ito
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
- Institute for Quantitative Biosciences, University of TokyoTokyoJapan
| | | | - Jens Goldammer
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
- Institute of Zoology, Biocenter Cologne, University of CologneCologneGermany
| | - Tanya Wolff
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Robert Svirskas
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | | | - Erika Neace
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | | | - Chelsea X Alvarado
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Dennis A Bailey
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Samantha Ballinger
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | | | - Brandon S Canino
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Natasha Cheatham
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Michael Cook
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Marisa Dreher
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Octave Duclos
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Bryon Eubanks
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Kelli Fairbanks
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Samantha Finley
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Nora Forknall
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Audrey Francis
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | | | - Emily M Joyce
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - SungJin Kim
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Nicole A Kirk
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Julie Kovalyak
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Shirley A Lauchie
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Alanna Lohff
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Charli Maldonado
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Emily A Manley
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Sari McLin
- Life Sciences Centre, Dalhousie UniversityHalifaxCanada
| | - Caroline Mooney
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Miatta Ndama
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Omotara Ogundeyi
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Nneoma Okeoma
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Christopher Ordish
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Nicholas Padilla
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | | | - Tyler Paterson
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Elliott E Phillips
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Emily M Phillips
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Neha Rampally
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Caitlin Ribeiro
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | | | - Jon Thomson Rymer
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Sean M Ryan
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Megan Sammons
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Anne K Scott
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Ashley L Scott
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Aya Shinomiya
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Claire Smith
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Kelsey Smith
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Natalie L Smith
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Margaret A Sobeski
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Alia Suleiman
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Jackie Swift
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Satoko Takemura
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Iris Talebi
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | | | - Emily Tenshaw
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Temour Tokhi
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - John J Walsh
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Tansy Yang
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | | | - Feng Li
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Ruchi Parekh
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Patricia K Rivlin
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Vivek Jayaraman
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Marta Costa
- Department of Zoology, University of CambridgeCambridgeUnited Kingdom
| | - Gregory SXE Jefferis
- MRC Laboratory of Molecular BiologyCambridgeUnited States
- Department of Zoology, University of CambridgeCambridgeUnited Kingdom
| | - Kei Ito
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
- Institute for Quantitative Biosciences, University of TokyoTokyoJapan
- Institute of Zoology, Biocenter Cologne, University of CologneCologneGermany
| | - Stephan Saalfeld
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Reed George
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Ian A Meinertzhagen
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
- Life Sciences Centre, Dalhousie UniversityHalifaxCanada
| | - Gerald M Rubin
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Harald F Hess
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Viren Jain
- Google Research, Google LLCZurichSwitzerland
| | - Stephen M Plaza
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
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43
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Isaacman-Beck J, Paik KC, Wienecke CFR, Yang HH, Fisher YE, Wang IE, Ishida IG, Maimon G, Wilson RI, Clandinin TR. SPARC enables genetic manipulation of precise proportions of cells. Nat Neurosci 2020; 23:1168-1175. [PMID: 32690967 PMCID: PMC7939234 DOI: 10.1038/s41593-020-0668-9] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Accepted: 06/12/2020] [Indexed: 11/17/2022]
Abstract
Many experimental approaches rely on controlling gene expression in select subsets of cells within an individual animal. However, reproducibly targeting transgene expression to specific fractions of a genetically defined cell type is challenging. We developed Sparse Predictive Activity through Recombinase Competition (SPARC), a generalizable toolkit that can express any effector in precise proportions of post-mitotic cells in Drosophila. Using this approach, we demonstrate targeted expression of many effectors in several cell types and apply these tools to calcium imaging of individual neurons and optogenetic manipulation of sparse cell populations in vivo.
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Affiliation(s)
| | - Kristine C Paik
- Department of Neurobiology, Stanford University, Stanford, CA, USA.,Department of Medicine, Weill Cornell Medical College, New York, NY, USA
| | | | - Helen H Yang
- Department of Neurobiology and Howard Hughes Medical Institute, Harvard Medical School, Boston, MA, USA
| | - Yvette E Fisher
- Department of Neurobiology and Howard Hughes Medical Institute, Harvard Medical School, Boston, MA, USA
| | - Irving E Wang
- Department of Neurobiology, Stanford University, Stanford, CA, USA.,Freenome, South San Francisco, CA, USA
| | - Itzel G Ishida
- Laboratory of Integrative Brain Function and Howard Hughes Medical Institute, The Rockefeller University, New York, NY, USA
| | - Gaby Maimon
- Laboratory of Integrative Brain Function and Howard Hughes Medical Institute, The Rockefeller University, New York, NY, USA
| | - Rachel I Wilson
- Department of Neurobiology and Howard Hughes Medical Institute, Harvard Medical School, Boston, MA, USA
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44
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Abstract
Research over the last 20 years has firmly established the existence of sleep states across the animal kingdom. Work in non-mammalian animal models such as nematodes, fruit flies, and zebrafish has now uncovered many evolutionarily conserved aspects of sleep physiology and regulation, including shared circuit architecture, homeostatic and circadian control elements, and principles linking sleep physiology to function. Non-mammalian sleep research is now shedding light on fundamental aspects of the genetic and neuronal circuit regulation of sleep, with direct implications for the understanding of how sleep is regulated in mammals.
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Affiliation(s)
- Declan G. Lyons
- Department of Cell and Developmental Biology, University College London, United Kingdom, WC1E 6BT
| | - Jason Rihel
- Department of Cell and Developmental Biology, University College London, United Kingdom, WC1E 6BT
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45
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Hensgen R, England L, Homberg U, Pfeiffer K. Neuroarchitecture of the central complex in the brain of the honeybee: Neuronal cell types. J Comp Neurol 2020; 529:159-186. [PMID: 32374034 DOI: 10.1002/cne.24941] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 04/30/2020] [Accepted: 04/30/2020] [Indexed: 12/11/2022]
Abstract
The central complex (CX) in the insect brain is a higher order integration center that controls a number of behaviors, most prominently goal directed locomotion. The CX comprises the protocerebral bridge (PB), the upper division of the central body (CBU), the lower division of the central body (CBL), and the paired noduli (NO). Although spatial orientation has been extensively studied in honeybees at the behavioral level, most electrophysiological and anatomical analyses have been carried out in other insect species, leaving the morphology and physiology of neurons that constitute the CX in the honeybee mostly enigmatic. The goal of this study was to morphologically identify neuronal cell types of the CX in the honeybee Apis mellifera. By performing iontophoretic dye injections into the CX, we traced 16 subtypes of neuron that connect a subdivision of the CX with other regions in the bee's central brain, and eight subtypes that mainly interconnect different subdivisions of the CX. They establish extensive connections between the CX and the lateral complex, the superior protocerebrum and the posterior protocerebrum. Characterized neuron classes and subtypes are morphologically similar to those described in other insects, suggesting considerable conservation in the neural network relevant for orientation.
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Affiliation(s)
- Ronja Hensgen
- Animal Physiology, Department of Biology, Philipps-Universität Marburg, Marburg, Germany
| | - Laura England
- Animal Physiology, Department of Biology, Philipps-Universität Marburg, Marburg, Germany
| | - Uwe Homberg
- Animal Physiology, Department of Biology, Philipps-Universität Marburg, Marburg, Germany
| | - Keram Pfeiffer
- Behavioral Physiology and Sociobiology (Zoology II), Biozentrum, University of Würzburg, Würzburg, Germany
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Hartenstein V, Omoto JJ, Lovick JK. The role of cell lineage in the development of neuronal circuitry and function. Dev Biol 2020; 475:165-180. [PMID: 32017903 DOI: 10.1016/j.ydbio.2020.01.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 01/23/2020] [Accepted: 01/23/2020] [Indexed: 12/13/2022]
Abstract
Complex nervous systems have a modular architecture, whereby reiterative groups of neurons ("modules") that share certain structural and functional properties are integrated into large neural circuits. Neurons develop from proliferating progenitor cells that, based on their location and time of appearance, are defined by certain genetic programs. Given that genes expressed by a given progenitor play a fundamental role in determining the properties of its lineage (i.e., the neurons descended from that progenitor), one efficient developmental strategy would be to have lineages give rise to the structural modules of the mature nervous system. It is clear that this strategy plays an important role in neural development of many invertebrate animals, notably insects, where the availability of genetic techniques has made it possible to analyze the precise relationship between neuronal origin and differentiation since several decades. Similar techniques, developed more recently in the vertebrate field, reveal that functional modules of the mammalian cerebral cortex are also likely products of developmentally defined lineages. We will review studies that relate cell lineage to circuitry and function from a comparative developmental perspective, aiming at enhancing our understanding of neural progenitors and their lineages, and translating findings acquired in different model systems into a common conceptual framework.
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Affiliation(s)
- Volker Hartenstein
- Department of Molecular Cell and Developmental Biology, University of California Los Angeles, Los Angeles, CA, 90095, USA.
| | - Jaison J Omoto
- Department of Molecular Cell and Developmental Biology, University of California Los Angeles, Los Angeles, CA, 90095, USA
| | - Jennifer K Lovick
- Department of Molecular Cell and Developmental Biology, University of California Los Angeles, Los Angeles, CA, 90095, USA
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47
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A Feedforward Circuit Regulates Action Selection of Pre-mating Courtship Behavior in Female Drosophila. Curr Biol 2020; 30:396-407.e4. [PMID: 31902724 DOI: 10.1016/j.cub.2019.11.065] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 10/21/2019] [Accepted: 11/21/2019] [Indexed: 01/01/2023]
Abstract
In the early phase of courtship, female fruit flies exhibit an acute rejection response to avoid unfavorable mating. This pre-mating rejection response is evolutionarily paralleled across species, but the molecular and neuronal basis of that behavior is unclear. Here, we show that a putative incoherent feedforward circuit comprising ellipsoid body neurons, cholinergic R4d, and its repressor GABAergic R2/R4m neurons regulates the pre-mating rejection response in the virgin female Drosophila melanogaster. Both R4d and R2/R4m are positively regulated, via specific dopamine receptors, by a subset of neurons in the dopaminergic PPM3 cluster. Genetic deprivation of GABAergic signal via GABAA receptor RNA interference in this circuit induces a massive rejection response, whereas activation of GABAergic R2/R4m or suppression of cholinergic R4d increases receptivity. Moreover, glutamatergic signaling via N-methyl-d-aspartate receptors induces NO-mediated retrograde regulation potentially from R4d to R2/R4m, likely providing flexible control of the behavioral switching from rejection to acceptance. Our study elucidates the molecular and neural mechanisms regulating the behavioral selection process of the pre-mating female.
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48
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Fisher YE, Lu J, D'Alessandro I, Wilson RI. Sensorimotor experience remaps visual input to a heading-direction network. Nature 2019; 576:121-125. [PMID: 31748749 PMCID: PMC7753972 DOI: 10.1038/s41586-019-1772-4] [Citation(s) in RCA: 84] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Accepted: 10/24/2019] [Indexed: 11/09/2022]
Abstract
In the Drosophila brain, 'compass' neurons track the orientation of the body and head (the fly's heading) during navigation 1,2. In the absence of visual cues, the compass neuron network estimates heading by integrating self-movement signals over time3,4. When a visual cue is present, the estimate of the network is more accurate1,3. Visual inputs to compass neurons are thought to originate from inhibitory neurons called R neurons (also known as ring neurons); the receptive fields of R neurons tile visual space5. The axon of each R neuron overlaps with the dendrites of every compass neuron6, raising the question of how visual cues are integrated into the compass. Here, using in vivo whole-cell recordings, we show that a visual cue can evoke synaptic inhibition in compass neurons and that R neurons mediate this inhibition. Each compass neuron is inhibited only by specific visual cue positions, indicating that many potential connections from R neurons onto compass neurons are actually weak or silent. We also show that the pattern of visually evoked inhibition can reorganize over minutes as the fly explores an altered virtual-reality environment. Using ensemble calcium imaging, we demonstrate that this reorganization causes persistent changes in the compass coordinate frame. Taken together, our data suggest a model in which correlated pre- and postsynaptic activity triggers associative long-term synaptic depression of visually evoked inhibition in compass neurons. Our findings provide evidence for the theoretical proposal that associative plasticity of sensory inputs, when combined with attractor dynamics, can reconcile self-movement information with changing external cues to generate a coherent sense of direction7-12.
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Affiliation(s)
- Yvette E Fisher
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
| | - Jenny Lu
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
| | | | - Rachel I Wilson
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA.
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49
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von Hadeln J, Hensgen R, Bockhorst T, Rosner R, Heidasch R, Pegel U, Quintero Pérez M, Homberg U. Neuroarchitecture of the central complex of the desert locust: Tangential neurons. J Comp Neurol 2019; 528:906-934. [PMID: 31625611 DOI: 10.1002/cne.24796] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 10/10/2019] [Accepted: 10/11/2019] [Indexed: 12/11/2022]
Abstract
The central complex (CX) comprises a group of midline neuropils in the insect brain, consisting of the protocerebral bridge (PB), the upper (CBU) and lower division (CBL) of the central body and a pair of globular noduli. It receives prominent input from the visual system and plays a major role in spatial orientation of the animals. Vertical slices and horizontal layers of the CX are formed by columnar, tangential, and pontine neurons. While pontine and columnar neurons have been analyzed in detail, especially in the fruit fly and desert locust, understanding of the organization of tangential cells is still rudimentary. As a basis for future functional studies, we have studied the morphologies of tangential neurons of the CX of the desert locust Schistocerca gregaria. Intracellular dye injections revealed 43 different types of tangential neuron, 8 of the PB, 5 of the CBL, 24 of the CBU, 2 of the noduli, and 4 innervating multiple substructures. Cell bodies of these neurons were located in 11 different clusters in the cell body rind. Judging from the presence of fine versus beaded terminals, the vast majority of these neurons provide input into the CX, especially from the lateral complex (LX), the superior protocerebrum, the posterior slope, and other surrounding brain areas, but not directly from the mushroom bodies. Connections are largely subunit- and partly layer-specific. No direct connections were found between the CBU and the CBL. Instead, both subdivisions are connected in parallel with the PB and distinct layers of the noduli.
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Affiliation(s)
- Joss von Hadeln
- Fachbereich Biologie, Tierphysiologie, and Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus Liebig University Giessen, Germany
| | - Ronja Hensgen
- Fachbereich Biologie, Tierphysiologie, and Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus Liebig University Giessen, Germany
| | - Tobias Bockhorst
- Fachbereich Biologie, Tierphysiologie, and Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus Liebig University Giessen, Germany
| | - Ronny Rosner
- Fachbereich Biologie, Tierphysiologie, and Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus Liebig University Giessen, Germany
| | - Ronny Heidasch
- Fachbereich Biologie, Tierphysiologie, and Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus Liebig University Giessen, Germany
| | - Uta Pegel
- Fachbereich Biologie, Tierphysiologie, and Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus Liebig University Giessen, Germany
| | - Manuel Quintero Pérez
- Fachbereich Biologie, Tierphysiologie, and Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus Liebig University Giessen, Germany
| | - Uwe Homberg
- Fachbereich Biologie, Tierphysiologie, and Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus Liebig University Giessen, Germany
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50
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Liu C, Meng Z, Wiggin TD, Yu J, Reed ML, Guo F, Zhang Y, Rosbash M, Griffith LC. A Serotonin-Modulated Circuit Controls Sleep Architecture to Regulate Cognitive Function Independent of Total Sleep in Drosophila. Curr Biol 2019; 29:3635-3646.e5. [PMID: 31668619 DOI: 10.1016/j.cub.2019.08.079] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Revised: 08/26/2019] [Accepted: 08/30/2019] [Indexed: 12/20/2022]
Abstract
Both the structure and the amount of sleep are important for brain function. Entry into deep, restorative stages of sleep is time dependent; short sleep bouts selectively eliminate these states. Fragmentation-induced cognitive dysfunction is a feature of many common human sleep pathologies. Whether sleep structure is normally regulated independent of the amount of sleep is unknown. Here, we show that in Drosophila melanogaster, activation of a subset of serotonergic neurons fragments sleep without major changes in the total amount of sleep, dramatically reducing long episodes that may correspond to deep sleep states. Disruption of sleep structure results in learning deficits that can be rescued by pharmacologically or genetically consolidating sleep. We identify two reciprocally connected sets of ellipsoid body neurons that form the heart of a serotonin-modulated circuit that controls sleep architecture. Taken together, these findings define a circuit essential for controlling the structure of sleep independent of its amount.
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Affiliation(s)
- Chang Liu
- Complex Systems, Brandeis University, Waltham, MA 02454, USA; Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen 518055, China.
| | - Zhiqiang Meng
- Complex Systems, Brandeis University, Waltham, MA 02454, USA; Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen 518055, China
| | | | - Junwei Yu
- Complex Systems, Brandeis University, Waltham, MA 02454, USA
| | - Martha L Reed
- Complex Systems, Brandeis University, Waltham, MA 02454, USA
| | - Fang Guo
- Complex Systems, Brandeis University, Waltham, MA 02454, USA; Howard Hughes Medical Institute, Brandeis University, Waltham, MA 02454, USA; Department of Neurobiology, Zhejiang University School of Medicine, Hangzhou, Zhejiang province 310058, China
| | - Yunpeng Zhang
- Complex Systems, Brandeis University, Waltham, MA 02454, USA
| | - Michael Rosbash
- Complex Systems, Brandeis University, Waltham, MA 02454, USA; Howard Hughes Medical Institute, Brandeis University, Waltham, MA 02454, USA
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