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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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Suárez-Grimalt R, Grunwald Kadow IC, Scheunemann L. An integrative sensor of body states: how the mushroom body modulates behavior depending on physiological context. Learn Mem 2024; 31:a053918. [PMID: 38876486 PMCID: PMC11199956 DOI: 10.1101/lm.053918.124] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Accepted: 04/08/2024] [Indexed: 06/16/2024]
Abstract
The brain constantly compares past and present experiences to predict the future, thereby enabling instantaneous and future behavioral adjustments. Integration of external information with the animal's current internal needs and behavioral state represents a key challenge of the nervous system. Recent advancements in dissecting the function of the Drosophila mushroom body (MB) at the single-cell level have uncovered its three-layered logic and parallel systems conveying positive and negative values during associative learning. This review explores a lesser-known role of the MB in detecting and integrating body states such as hunger, thirst, and sleep, ultimately modulating motivation and sensory-driven decisions based on the physiological state of the fly. State-dependent signals predominantly affect the activity of modulatory MB input neurons (dopaminergic, serotoninergic, and octopaminergic), but also induce plastic changes directly at the level of the MB intrinsic and output neurons. Thus, the MB emerges as a tightly regulated relay station in the insect brain, orchestrating neuroadaptations due to current internal and behavioral states leading to short- but also long-lasting changes in behavior. While these adaptations are crucial to ensure fitness and survival, recent findings also underscore how circuit motifs in the MB may reflect fundamental design principles that contribute to maladaptive behaviors such as addiction or depression-like symptoms.
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Affiliation(s)
- Raquel Suárez-Grimalt
- Institute for Biology/Genetics, Freie Universität Berlin, 14195 Berlin, Germany
- Institut für Neurophysiologie and NeuroCure Cluster of Excellence, Charité-Universitätsmedizin Berlin, 10117 Berlin, Germany
| | | | - Lisa Scheunemann
- Institute for Biology/Genetics, Freie Universität Berlin, 14195 Berlin, Germany
- Institut für Neurophysiologie and NeuroCure Cluster of Excellence, Charité-Universitätsmedizin Berlin, 10117 Berlin, Germany
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3
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Zaupa M, Nagaraj N, Sylenko A, Baier H, Sawamiphak S, Filosa A. The Calmodulin-interacting peptide Pcp4a regulates feeding state-dependent behavioral choice in zebrafish. Neuron 2024; 112:1150-1164.e6. [PMID: 38295792 DOI: 10.1016/j.neuron.2024.01.001] [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: 03/01/2023] [Revised: 10/06/2023] [Accepted: 01/02/2024] [Indexed: 04/06/2024]
Abstract
Animals constantly need to judge the valence of an object in their environment: is it potential food or a threat? The brain makes fundamental decisions on the appropriate behavioral strategy by integrating external information from sensory organs and internal signals related to physiological needs. For example, a hungry animal may take more risks than a satiated one when deciding to approach or avoid an object. Using a proteomic profiling approach, we identified the Calmodulin-interacting peptide Pcp4a as a key regulator of foraging-related decisions. Food intake reduced abundance of protein and mRNA of pcp4a via dopamine D2-like receptor-mediated repression of adenylate cyclase. Accordingly, deleting the pcp4a gene made zebrafish larvae more risk averse in a binary decision assay. Strikingly, neurons in the tectum became less responsive to prey-like visual stimuli in pcp4a mutants, thus biasing the behavior toward avoidance. This study pinpoints a molecular mechanism modulating behavioral choice according to internal state.
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Affiliation(s)
- Margherita Zaupa
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), 13092 Berlin, Germany; Freie Universität Berlin, Institute for Biology, 14195 Berlin, Germany
| | - Nagarjuna Nagaraj
- Biochemistry Core Facility, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
| | - Anna Sylenko
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), 13092 Berlin, Germany; Freie Universität Berlin, Institute for Biology, 14195 Berlin, Germany
| | - Herwig Baier
- Max Planck Institute for Biological Intelligence, 82152 Martinsried, Germany
| | - Suphansa Sawamiphak
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), 13092 Berlin, Germany
| | - Alessandro Filosa
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), 13092 Berlin, Germany.
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4
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Zhu L, Su Y, Ma S, Guo L, Yang S, Yu H. Comparative Proteomic Analysis Reveals Candidate Pathways Related to the Effect of Different Light Qualities on the Development of Mycelium and Fruiting Body of Pleurotus ostreatus. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024; 72:1361-1375. [PMID: 38166381 DOI: 10.1021/acs.jafc.3c06083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2024]
Abstract
Light affects the morphology and physiology of Pleurotus ostreatus. However, the underlying molecular mechanism of this effect remains unclear. In this study, a label-free comparative proteomic analysis was conducted to investigate the global protein expression profile of the mycelia and fruiting bodies of P. ostreatus PH11 growing under four different light quality treatments. Among all the 2234 P. ostreatus proteins, 1349 were quantifiable under all tested conditions. A total of 1100 differentially expressed proteins were identified by comparing the light group data with those of the darkness group. GO and KEGG enrichment analyses indicated that the oxidative phosphorylation, proteasome, and mRNA surveillance pathways were the most related pathways under the light condition. qRT-PCR verified that the expression of the white collar 1 protein was significantly enhanced under white light. Additionally, glutamine synthetase and aldehyde dehydrogenase played important roles during light exposure. This study provides valuable insight into the P. ostreatus light response mechanism, which will lay the foundation for improved cultivation.
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Affiliation(s)
- Liping Zhu
- Shandong Provincial Key Laboratory of Applied Mycology, School of Life Sciences, Qingdao Agricultural University, 700 Changcheng Road, Chengyang District, Qingdao, Shandong Province266109, People's Republic of China
| | - Yao Su
- Shandong Provincial Key Laboratory of Applied Mycology, School of Life Sciences, Qingdao Agricultural University, 700 Changcheng Road, Chengyang District, Qingdao, Shandong Province266109, People's Republic of China
| | - Shunan Ma
- Shandong Provincial Key Laboratory of Applied Mycology, School of Life Sciences, Qingdao Agricultural University, 700 Changcheng Road, Chengyang District, Qingdao, Shandong Province266109, People's Republic of China
| | - Lizhong Guo
- Shandong Provincial Key Laboratory of Applied Mycology, School of Life Sciences, Qingdao Agricultural University, 700 Changcheng Road, Chengyang District, Qingdao, Shandong Province266109, People's Republic of China
| | - Song Yang
- Shandong Provincial Key Laboratory of Applied Mycology, School of Life Sciences, Qingdao Agricultural University, 700 Changcheng Road, Chengyang District, Qingdao, Shandong Province266109, People's Republic of China
| | - Hao Yu
- Shandong Provincial Key Laboratory of Applied Mycology, School of Life Sciences, Qingdao Agricultural University, 700 Changcheng Road, Chengyang District, Qingdao, Shandong Province266109, People's Republic of China
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Arican C, Schmitt FJ, Rössler W, Strube-Bloss MF, Nawrot MP. The mushroom body output encodes behavioral decision during sensory-motor transformation. Curr Biol 2023; 33:4217-4224.e4. [PMID: 37657449 DOI: 10.1016/j.cub.2023.08.016] [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: 03/21/2023] [Revised: 06/30/2023] [Accepted: 08/03/2023] [Indexed: 09/03/2023]
Abstract
Animals form a behavioral decision by evaluating sensory evidence on the background of past experiences and the momentary motivational state. In insects, we still lack understanding of how and at which stage of the recurrent sensory-motor pathway behavioral decisions are formed. The mushroom body (MB), a central brain structure in insects1 and crustaceans,2,3 integrates sensory input of different modalities4,5,6 with the internal state, the behavioral state, and external sensory context7,8,9,10 through a large number of recurrent, mostly neuromodulatory inputs,11,12 implicating a functional role for MBs in state-dependent sensory-motor transformation.13,14 A number of classical conditioning studies in honeybees15,16 and fruit flies17,18,19 have provided accumulated evidence that at its output, the MB encodes the valence of a sensory stimulus with respect to its behavioral relevance. Recent work has extended this notion of valence encoding to the context of innate behaviors.8,20,21,22 Here, we co-analyzed a defined feeding behavior and simultaneous extracellular single-unit recordings from MB output neurons (MBONs) in the cockroach in response to timed sensory stimulation with odors. We show that clear neuronal responses occurred almost exclusively during behaviorally responded trials. Early MBON responses to the sensory stimulus preceded the feeding behavior and predicted its occurrence or non-occurrence from the single-trial population activity. Our results therefore suggest that at its output, the MB does not merely encode sensory stimulus valence. We hypothesize instead that the MB output represents an integrated signal of internal state, momentary environmental conditions, and experience-dependent memory to encode a behavioral decision.
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Affiliation(s)
- Cansu Arican
- Computational Systems Neuroscience, Institute of Zoology, University of Cologne, Zülpicher Str. 47b, 50674 Cologne, Germany.
| | - Felix Johannes Schmitt
- Computational Systems Neuroscience, Institute of Zoology, University of Cologne, Zülpicher Str. 47b, 50674 Cologne, Germany
| | - Wolfgang Rössler
- Behavioral Physiology and Sociobiology (Zoology II), Biozentrum, University of Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Martin Fritz Strube-Bloss
- Department of Biological Cybernetics and Theoretical Biology, University of Bielefeld, Universitätsstr. 25, 33615 Bielefeld, Germany
| | - Martin Paul Nawrot
- Computational Systems Neuroscience, Institute of Zoology, University of Cologne, Zülpicher Str. 47b, 50674 Cologne, Germany.
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6
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Lin S. Internal-state-dependent modulation of olfactory responses: a tale of dopamine neurons in the adult Drosophila mushroom body. CURRENT OPINION IN INSECT SCIENCE 2023; 59:101104. [PMID: 37611806 DOI: 10.1016/j.cois.2023.101104] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 08/02/2023] [Accepted: 08/17/2023] [Indexed: 08/25/2023]
Abstract
Olfaction is a vital sense that insects use to forage and interact with each other. When an insect smells an odor, its nervous system processes the odor information and transforms it into an appropriate behavioral decision. Olfactory processing and transformation are not label-lined, but instead are modulated by internal states. The vinegar fly, Drosophila melanogaster, has become a primary model organism for studying this modulation. It has been observed that internal state modulates olfactory behaviors in multiple sites of the fly brain. In this review article, I focus on the mushroom body, a computational center in the fly brain, and discuss how the dopamine system in this brain region mediates internal-state signals and shapes olfactory responses in adult flies.
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Affiliation(s)
- Suewei Lin
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan.
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7
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Chiang MH, Lin YC, Chen SF, Lee PS, Fu TF, Wu T, Wu CL. Independent insulin signaling modulators govern hot avoidance under different feeding states. PLoS Biol 2023; 21:e3002332. [PMID: 37847673 PMCID: PMC10581474 DOI: 10.1371/journal.pbio.3002332] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2023] [Accepted: 09/11/2023] [Indexed: 10/19/2023] Open
Abstract
Thermosensation is critical for the survival of animals. However, mechanisms through which nutritional status modulates thermosensation remain unclear. Herein, we showed that hungry Drosophila exhibit a strong hot avoidance behavior (HAB) compared to food-sated flies. We identified that hot stimulus increases the activity of α'β' mushroom body neurons (MBns), with weak activity in the sated state and strong activity in the hungry state. Furthermore, we showed that α'β' MBn receives the same level of hot input from the mALT projection neurons via cholinergic transmission in sated and hungry states. Differences in α'β' MBn activity between food-sated and hungry flies following heat stimuli are regulated by distinct Drosophila insulin-like peptides (Dilps). Dilp2 is secreted by insulin-producing cells (IPCs) and regulates HAB during satiety, whereas Dilp6 is secreted by the fat body and regulates HAB during the hungry state. We observed that Dilp2 induces PI3K/AKT signaling, whereas Dilp6 induces Ras/ERK signaling in α'β' MBn to regulate HAB in different feeding conditions. Finally, we showed that the 2 α'β'-related MB output neurons (MBONs), MBON-α'3 and MBON-β'1, are necessary for the output of integrated hot avoidance information from α'β' MBn. Our results demonstrate the presence of dual insulin modulation pathways in α'β' MBn, which are important for suitable behavioral responses in Drosophila during thermoregulation under different feeding states.
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Affiliation(s)
- Meng-Hsuan Chiang
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Yu-Chun Lin
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan
- Department of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Sheng-Fu Chen
- NHRI Institute of Biomedical Engineering & Nanomedicine, Miaoli, Taiwan
| | - Peng-Shiuan Lee
- Department of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Tsai-Feng Fu
- Department of Applied Chemistry, National Chi Nan University, Nantou, Taiwan
| | - Tony Wu
- Department of Neurology, New Taipei Municipal TuCheng Hospital, Chang Gung Memorial Hospital, New Taipei City, Taiwan
| | - Chia-Lin Wu
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan
- Department of Neurology, New Taipei Municipal TuCheng Hospital, Chang Gung Memorial Hospital, New Taipei City, Taiwan
- Department of Biochemistry, College of Medicine, Chang Gung University, Taoyuan, Taiwan
- Brain Research Center, National Tsing Hua University, Hsinchu, Taiwan
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8
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MaBouDi H, Marshall JAR, Dearden N, Barron AB. How honey bees make fast and accurate decisions. eLife 2023; 12:e86176. [PMID: 37365884 PMCID: PMC10299826 DOI: 10.7554/elife.86176] [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: 01/14/2023] [Accepted: 05/24/2023] [Indexed: 06/28/2023] Open
Abstract
Honey bee ecology demands they make both rapid and accurate assessments of which flowers are most likely to offer them nectar or pollen. To understand the mechanisms of honey bee decision-making, we examined their speed and accuracy of both flower acceptance and rejection decisions. We used a controlled flight arena that varied both the likelihood of a stimulus offering reward and punishment and the quality of evidence for stimuli. We found that the sophistication of honey bee decision-making rivalled that reported for primates. Their decisions were sensitive to both the quality and reliability of evidence. Acceptance responses had higher accuracy than rejection responses and were more sensitive to changes in available evidence and reward likelihood. Fast acceptances were more likely to be correct than slower acceptances; a phenomenon also seen in primates and indicative that the evidence threshold for a decision changes dynamically with sampling time. To investigate the minimally sufficient circuitry required for these decision-making capacities, we developed a novel model of decision-making. Our model can be mapped to known pathways in the insect brain and is neurobiologically plausible. Our model proposes a system for robust autonomous decision-making with potential application in robotics.
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Affiliation(s)
- HaDi MaBouDi
- Department of Computer Science, University of SheffieldSheffieldUnited Kingdom
- Sheffield Neuroscience Institute, University of SheffieldSheffieldUnited Kingdom
| | - James AR Marshall
- Department of Computer Science, University of SheffieldSheffieldUnited Kingdom
- Sheffield Neuroscience Institute, University of SheffieldSheffieldUnited Kingdom
| | - Neville Dearden
- Department of Computer Science, University of SheffieldSheffieldUnited Kingdom
| | - Andrew B Barron
- Department of Computer Science, University of SheffieldSheffieldUnited Kingdom
- School of Natural Sciences, Macquarie UniversityNorth RydeAustralia
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Noyes NC, Davis RL. Innate and learned odor-guided behaviors utilize distinct molecular signaling pathways in a shared dopaminergic circuit. Cell Rep 2023; 42:112026. [PMID: 36701232 PMCID: PMC10366338 DOI: 10.1016/j.celrep.2023.112026] [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: 06/03/2022] [Revised: 11/16/2022] [Accepted: 01/10/2023] [Indexed: 01/26/2023] Open
Abstract
Odor-based learning and innate odor-driven behavior have been hypothesized to require separate neuronal circuitry. Contrary to this notion, innate behavior and olfactory learning were recently shown to share circuitry that includes the Drosophila mushroom body (MB). But how a single circuit drives two discrete behaviors remains unknown. Here, we define an MB circuit responsible for both olfactory learning and innate odor avoidance and the distinct dDA1 dopamine receptor-dependent signaling pathways that mediate these behaviors. Associative learning and learning-induced MB plasticity require rutabaga-encoded adenylyl cyclase activity in the MB. In contrast, innate odor preferences driven by naive MB neurotransmission are rutabaga independent, requiring the adenylyl cyclase ACXD. Both learning and innate odor preferences converge on PKA and the downstream MBON-γ2α'1. Importantly, the utilization of this shared circuitry for innate behavior only becomes apparent with hunger, indicating that hardwired innate behavior becomes more flexible during states of stress.
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Affiliation(s)
- Nathaniel C Noyes
- Department of Neuroscience, UF Scripps Biomedical Research, 130 Scripps Way #3C2, Jupiter, FL 33458, USA
| | - Ronald L Davis
- Department of Neuroscience, UF Scripps Biomedical Research, 130 Scripps Way #3C2, Jupiter, FL 33458, USA.
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10
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Fabian B, Sachse S. Experience-dependent plasticity in the olfactory system of Drosophila melanogaster and other insects. Front Cell Neurosci 2023; 17:1130091. [PMID: 36923450 PMCID: PMC10010147 DOI: 10.3389/fncel.2023.1130091] [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: 12/22/2022] [Accepted: 02/07/2023] [Indexed: 02/24/2023] Open
Abstract
It is long known that the nervous system of vertebrates can be shaped by internal and external factors. On the other hand, the nervous system of insects was long assumed to be stereotypic, although evidence for plasticity effects accumulated for several decades. To cover the topic comprehensively, this review recapitulates the establishment of the term "plasticity" in neuroscience and introduces its original meaning. We describe the basic composition of the insect olfactory system using Drosophila melanogaster as a representative example and outline experience-dependent plasticity effects observed in this part of the brain in a variety of insects, including hymenopterans, lepidopterans, locusts, and flies. In particular, we highlight recent advances in the study of experience-dependent plasticity effects in the olfactory system of D. melanogaster, as it is the most accessible olfactory system of all insect species due to the genetic tools available. The partly contradictory results demonstrate that morphological, physiological and behavioral changes in response to long-term olfactory stimulation are more complex than previously thought. Different molecular mechanisms leading to these changes were unveiled in the past and are likely responsible for this complexity. We discuss common problems in the study of experience-dependent plasticity, ways to overcome them, and future directions in this area of research. In addition, we critically examine the transferability of laboratory data to natural systems to address the topic as holistically as possible. As a mechanism that allows organisms to adapt to new environmental conditions, experience-dependent plasticity contributes to an animal's resilience and is therefore a crucial topic for future research, especially in an era of rapid environmental changes.
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Affiliation(s)
| | - Silke Sachse
- Research Group Olfactory Coding, Max Planck Institute for Chemical Ecology, Jena, Germany
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11
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Kanaoka Y, Onodera K, Watanabe K, Hayashi Y, Usui T, Uemura T, Hattori Y. Inter-organ Wingless/Ror/Akt signaling regulates nutrient-dependent hyperarborization of somatosensory neurons. eLife 2023; 12:79461. [PMID: 36647607 PMCID: PMC9844989 DOI: 10.7554/elife.79461] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Accepted: 12/11/2022] [Indexed: 01/18/2023] Open
Abstract
Nutrition in early life has profound effects on an organism, altering processes such as organogenesis. However, little is known about how specific nutrients affect neuronal development. Dendrites of class IV dendritic arborization neurons in Drosophila larvae become more complex when the larvae are reared on a low-yeast diet compared to a high-yeast diet. Our systematic search for key nutrients revealed that the neurons increase their dendritic terminal densities in response to a combined deficiency in vitamins, metal ions, and cholesterol. The deficiency of these nutrients upregulates Wingless in a closely located tissue, body wall muscle. Muscle-derived Wingless activates Akt in the neurons through the receptor tyrosine kinase Ror, which promotes the dendrite branching. In larval muscles, the expression of wingless is regulated not only in this key nutrient-dependent manner, but also by the JAK/STAT signaling pathway. Additionally, the low-yeast diet blunts neuronal light responsiveness and light avoidance behavior, which may help larvae optimize their survival strategies under low-nutritional conditions. Together, our studies illustrate how the availability of specific nutrients affects neuronal development through inter-organ signaling.
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Affiliation(s)
| | - Koun Onodera
- Graduate School of Biostudies, Kyoto UniversityKyotoJapan
| | - Kaori Watanabe
- Graduate School of Biostudies, Kyoto UniversityKyotoJapan
| | - Yusaku Hayashi
- Graduate School of Biostudies, Kyoto UniversityKyotoJapan
| | - Tadao Usui
- Graduate School of Biostudies, Kyoto UniversityKyotoJapan
| | - Tadashi Uemura
- Graduate School of Biostudies, Kyoto UniversityKyotoJapan
- Research Center for Dynamic Living Systems, Kyoto UniversityKyotoJapan
- AMED-CRESTTokyoJapan
| | - Yukako Hattori
- Graduate School of Biostudies, Kyoto UniversityKyotoJapan
- JST FORESTTokyoJapan
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12
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Zocchi D, Ye ES, Hauser V, O'Connell TF, Hong EJ. Parallel encoding of CO 2 in attractive and aversive glomeruli by selective lateral signaling between olfactory afferents. Curr Biol 2022; 32:4225-4239.e7. [PMID: 36070776 PMCID: PMC9561050 DOI: 10.1016/j.cub.2022.08.025] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 07/13/2022] [Accepted: 08/10/2022] [Indexed: 12/14/2022]
Abstract
We describe a novel form of selective crosstalk between specific classes of primary olfactory receptor neurons (ORNs) in the Drosophila antennal lobe. Neurotransmitter release from ORNs is driven by two distinct sources of excitation: direct activity derived from the odorant receptor and stimulus-selective lateral signals originating from stereotypic subsets of other ORNs. Consequently, the level of presynaptic neurotransmitter release from an ORN can be significantly dissociated from its firing rate. Stimulus-selective lateral signaling results in the distributed representation of CO2-a behaviorally important environmental cue that directly excites a single ORN class-in multiple olfactory glomeruli, each with distinct response dynamics. CO2-sensitive glomeruli coupled to behavioral attraction respond preferentially to fast changes in CO2 concentration, whereas those coupled to behavioral aversion more closely follow absolute levels of CO2. Behavioral responses to CO2 also depend on the temporal structure of the stimulus: flies walk upwind to fluctuating, but not sustained, pulses of CO2. Stimulus-selective lateral signaling generalizes to additional odors and glomeruli, revealing a subnetwork of lateral interactions between ORNs that reshapes the spatial and temporal structure of odor representations in a stimulus-specific manner.
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Affiliation(s)
- Dhruv Zocchi
- Division of Biology & Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA; Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Emily S Ye
- Division of Biology & Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Virginie Hauser
- Division of Biology & Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Thomas F O'Connell
- Division of Biology & Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Elizabeth J Hong
- Division of Biology & Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA.
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13
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Rohlfs C. A descriptive analysis of olfactory sensation and memory in Drosophila and its relation to artificial neural networks. Neurocomputing 2022. [DOI: 10.1016/j.neucom.2022.10.068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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14
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Endo K, Kazama H. Central organization of a high-dimensional odor space. Curr Opin Neurobiol 2022; 73:102528. [DOI: 10.1016/j.conb.2022.102528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Revised: 02/17/2022] [Accepted: 02/24/2022] [Indexed: 11/03/2022]
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15
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He J, Tuo W, Zhang X, Dai Y, Fang M, Zhou T, Xiu M, Liu Y. Olfactory Senses Modulate Food Consumption and Physiology in Drosophila melanogaster. Front Behav Neurosci 2022; 16:788633. [PMID: 35431829 PMCID: PMC9011337 DOI: 10.3389/fnbeh.2022.788633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2021] [Accepted: 02/22/2022] [Indexed: 11/13/2022] Open
Abstract
Both sensory and metabolic processes guide food intake. Olfactory inputs help coordinate food appreciation and selection, but their role in food consumption and post-feeding physiology remains poorly understood. In this study, using Drosophila melanogaster as a model system, we investigated the effects of olfactory sensory neurons (OSNs) on food consumption, metabolism, and stress responses. We found that dysfunction of OSNs affects diverse processes, including decreased food consumption, increased triacylglycerol level, enhanced stress resistance to starvation or desiccation, and decreased cold resistance. Decreased neuropeptide F receptor (NPFR) level or increased insulin activity in OSNs inhibited food consumption, while impaired NPF signaling or insulin signaling in OSNs increased resistance to starvation and desiccation. These studies provide insights into the function of the olfactory system in control of feeding behaviors and physiology.
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Affiliation(s)
- Jianzheng He
- Provincial-Level Key Laboratory for Molecular Medicine of Major Diseases and the Prevention and Treatment with Traditional Chinese Medicine Research in Gansu Colleges and University, Gansu University of Chinese Medicine, Lanzhou, China
- College of Basic Medicine, Gansu University of Chinese Medicine, Lanzhou, China
- Key Laboratory for Transfer of Dunhuang Medicine at the Provincial and Ministerial Level, Gansu University of Traditional Chinese Medicine, Lanzhou, China
| | - Wenjuan Tuo
- Provincial-Level Key Laboratory for Molecular Medicine of Major Diseases and the Prevention and Treatment with Traditional Chinese Medicine Research in Gansu Colleges and University, Gansu University of Chinese Medicine, Lanzhou, China
- College of Basic Medicine, Gansu University of Chinese Medicine, Lanzhou, China
| | - Xueyan Zhang
- College of Public Health, Gansu University of Chinese Medicine, Lanzhou, China
| | - Yuting Dai
- College of Public Health, Gansu University of Chinese Medicine, Lanzhou, China
| | - Ming Fang
- Provincial-Level Key Laboratory for Molecular Medicine of Major Diseases and the Prevention and Treatment with Traditional Chinese Medicine Research in Gansu Colleges and University, Gansu University of Chinese Medicine, Lanzhou, China
- College of Basic Medicine, Gansu University of Chinese Medicine, Lanzhou, China
| | - Ting Zhou
- Provincial-Level Key Laboratory for Molecular Medicine of Major Diseases and the Prevention and Treatment with Traditional Chinese Medicine Research in Gansu Colleges and University, Gansu University of Chinese Medicine, Lanzhou, China
| | - Minghui Xiu
- Provincial-Level Key Laboratory for Molecular Medicine of Major Diseases and the Prevention and Treatment with Traditional Chinese Medicine Research in Gansu Colleges and University, Gansu University of Chinese Medicine, Lanzhou, China
- Key Laboratory for Transfer of Dunhuang Medicine at the Provincial and Ministerial Level, Gansu University of Traditional Chinese Medicine, Lanzhou, China
- College of Public Health, Gansu University of Chinese Medicine, Lanzhou, China
- *Correspondence: Minghui Xiu,
| | - Yongqi Liu
- Provincial-Level Key Laboratory for Molecular Medicine of Major Diseases and the Prevention and Treatment with Traditional Chinese Medicine Research in Gansu Colleges and University, Gansu University of Chinese Medicine, Lanzhou, China
- Key Laboratory for Transfer of Dunhuang Medicine at the Provincial and Ministerial Level, Gansu University of Traditional Chinese Medicine, Lanzhou, China
- Yongqi Liu,
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16
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Devineni AV, Scaplen KM. Neural Circuits Underlying Behavioral Flexibility: Insights From Drosophila. Front Behav Neurosci 2022; 15:821680. [PMID: 35069145 PMCID: PMC8770416 DOI: 10.3389/fnbeh.2021.821680] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Accepted: 12/14/2021] [Indexed: 11/16/2022] Open
Abstract
Behavioral flexibility is critical to survival. Animals must adapt their behavioral responses based on changes in the environmental context, internal state, or experience. Studies in Drosophila melanogaster have provided insight into the neural circuit mechanisms underlying behavioral flexibility. Here we discuss how Drosophila behavior is modulated by internal and behavioral state, environmental context, and learning. We describe general principles of neural circuit organization and modulation that underlie behavioral flexibility, principles that are likely to extend to other species.
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Affiliation(s)
- Anita V. Devineni
- Department of Biology, Emory University, Atlanta, GA, United States
- Zuckerman Mind Brain Institute, Columbia University, New York, NY, United States
| | - Kristin M. Scaplen
- Department of Psychology, Bryant University, Smithfield, RI, United States
- Center for Health and Behavioral Studies, Bryant University, Smithfield, RI, United States
- Department of Neuroscience, Brown University, Providence, RI, United States
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17
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Eschbach C, Fushiki A, Winding M, Afonso B, Andrade IV, Cocanougher BT, Eichler K, Gepner R, Si G, Valdes-Aleman J, Fetter RD, Gershow M, Jefferis GS, Samuel AD, Truman JW, Cardona A, Zlatic M. Circuits for integrating learned and innate valences in the insect brain. eLife 2021; 10:62567. [PMID: 34755599 PMCID: PMC8616581 DOI: 10.7554/elife.62567] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 11/03/2021] [Indexed: 12/23/2022] Open
Abstract
Animal behavior is shaped both by evolution and by individual experience. Parallel brain pathways encode innate and learned valences of cues, but the way in which they are integrated during action-selection is not well understood. We used electron microscopy to comprehensively map with synaptic resolution all neurons downstream of all mushroom body (MB) output neurons (encoding learned valences) and characterized their patterns of interaction with lateral horn (LH) neurons (encoding innate valences) in Drosophila larva. The connectome revealed multiple convergence neuron types that receive convergent MB and LH inputs. A subset of these receives excitatory input from positive-valence MB and LH pathways and inhibitory input from negative-valence MB pathways. We confirmed functional connectivity from LH and MB pathways and behavioral roles of two of these neurons. These neurons encode integrated odor value and bidirectionally regulate turning. Based on this, we speculate that learning could potentially skew the balance of excitation and inhibition onto these neurons and thereby modulate turning. Together, our study provides insights into the circuits that integrate learned and innate valences to modify behavior.
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Affiliation(s)
- Claire Eschbach
- HHMI Janelia Research Campus, Richmond, United Kingdom.,Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom.,Department of Zoology, University of Cambridge, Cambridge, United Kingdom
| | - Akira Fushiki
- HHMI Janelia Research Campus, Richmond, United Kingdom.,Department of Neuroscience & Neurology, & Zuckerman Mind Brain Institute, Columbia University, New York, United States
| | - Michael Winding
- HHMI Janelia Research Campus, Richmond, United Kingdom.,Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom.,Department of Zoology, University of Cambridge, Cambridge, United Kingdom
| | - Bruno Afonso
- HHMI Janelia Research Campus, Richmond, United Kingdom
| | - Ingrid V Andrade
- HHMI Janelia Research Campus, Richmond, United Kingdom.,Department of Molecular, Cell and Developmental Biology, University California Los Angeles, Los Angeles, United States
| | - Benjamin T Cocanougher
- HHMI Janelia Research Campus, Richmond, United Kingdom.,Department of Zoology, University of Cambridge, Cambridge, United Kingdom
| | - Katharina Eichler
- HHMI Janelia Research Campus, Richmond, United Kingdom.,Department of Zoology, University of Cambridge, Cambridge, United Kingdom
| | - Ruben Gepner
- Department of Physics, New York University, New York, United States
| | - Guangwei Si
- Department of Physics, Harvard University, Cambridge, United States.,Center for Brain Science, Harvard University, Cambridge, United States
| | - Javier Valdes-Aleman
- HHMI Janelia Research Campus, Richmond, United Kingdom.,Department of Zoology, University of Cambridge, Cambridge, United Kingdom.,Department of Molecular, Cell and Developmental Biology, University California Los Angeles, Los Angeles, United States
| | | | - Marc Gershow
- Department of Physics, New York University, New York, United States.,Center for Neural Science, New York University, New York, United States.,Neuroscience Institute, New York University, New York, United States
| | - Gregory Sxe Jefferis
- Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom.,Department of Zoology, University of Cambridge, Cambridge, United Kingdom
| | - Aravinthan Dt Samuel
- Department of Physics, Harvard University, Cambridge, United States.,Center for Brain Science, Harvard University, Cambridge, United States
| | - James W Truman
- HHMI Janelia Research Campus, Richmond, United Kingdom.,Department of Biology, University of Washington, Seattle, United States
| | - Albert Cardona
- HHMI Janelia Research Campus, Richmond, United Kingdom.,Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom.,Department of Physiology, Development & Neuroscience, University of Cambridge, Cambridge, United Kingdom
| | - Marta Zlatic
- HHMI Janelia Research Campus, Richmond, United Kingdom.,Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom.,Department of Zoology, University of Cambridge, Cambridge, United Kingdom
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18
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Kanwal JK, Coddington E, Frazer R, Limbania D, Turner G, Davila KJ, Givens MA, Williams V, Datta SR, Wasserman S. Internal State: Dynamic, Interconnected Communication Loops Distributed Across Body, Brain, and Time. Integr Comp Biol 2021; 61:867-886. [PMID: 34115114 PMCID: PMC8623242 DOI: 10.1093/icb/icab101] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Internal state profoundly alters perception and behavior. For example, a starved fly may approach and consume foods that it would otherwise find undesirable. A socially engaged newt may remain engaged in the presence of a predator, whereas a solitary newt would otherwise attempt to escape. Yet, the definition of internal state is fluid and ill-defined. As an interdisciplinary group of scholars spanning five career stages (from undergraduate to full professor) and six academic institutions, we came together in an attempt to provide an operational definition of internal state that could be useful in understanding the behavior and the function of nervous systems, at timescales relevant to the individual. In this perspective, we propose to define internal state through an integrative framework centered on dynamic and interconnected communication loops within and between the body and the brain. This framework is informed by a synthesis of historical and contemporary paradigms used by neurobiologists, ethologists, physiologists, and endocrinologists. We view internal state as composed of both spatially distributed networks (body-brain communication loops), and temporally distributed mechanisms that weave together neural circuits, physiology, and behavior. Given the wide spatial and temporal scales at which internal state operates-and therefore the broad range of scales at which it could be defined-we choose to anchor our definition in the body. Here we focus on studies that highlight body-to-brain signaling; body represented in endocrine signaling, and brain represented in sensory signaling. This integrative framework of internal state potentially unites the disparate paradigms often used by scientists grappling with body-brain interactions. We invite others to join us as we examine approaches and question assumptions to study the underlying mechanisms and temporal dynamics of internal state.
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Affiliation(s)
- Jessleen K Kanwal
- Division of Biology and Biological Engineering, California Institute of
Technology, Pasadena, CA 91125, USA
| | - Emma Coddington
- Department of Biology, Willamette University, Salem, OR
97301, USA
| | - Rachel Frazer
- Division of Neurobiology and Behavior, Columbia Universitye,
New York, NY 10027, USA
| | - Daniela Limbania
- Department of Neuroscience, Wellesley College, Wellesley, MA
02481, USA
| | - Grace Turner
- Department of Neuroscience, Wellesley College, Wellesley, MA
02481, USA
| | - Karla J Davila
- Department of Biology, Willamette University, Salem, OR
97301, USA
| | - Michael A Givens
- Department of Biology, Willamette University, Salem, OR
97301, USA
| | - Valarie Williams
- Department of Dance, The Ohio State University, Columbus, OH
43210, USA
| | | | - Sara Wasserman
- Department of Neuroscience, Wellesley College, Wellesley, MA
02481, USA
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19
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Poivet E, Gallot A, Montagné N, Senin P, Monsempès C, Legeai F, Jacquin-Joly E. Transcriptome Profiling of Starvation in the Peripheral Chemosensory Organs of the Crop Pest Spodoptera littoralis Caterpillars. INSECTS 2021; 12:insects12070573. [PMID: 34201462 PMCID: PMC8303696 DOI: 10.3390/insects12070573] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 06/05/2021] [Accepted: 06/18/2021] [Indexed: 11/25/2022]
Abstract
Simple Summary Starvation increases olfactory sensitivity in a manner that enhances the search for food in animals, including insects. However, the molecular mechanisms via which starvation modulates olfactory receptor neuron function are poorly understood. In this study, we sequenced and compared the whole transcriptomes of the main olfactory organs (antennae and palps) of fed and starved caterpillars from the species Spodoptera littoralis. We revealed that transcripts involved in several biological processes are regulated upon starvation. These processes include glucose metabolism, immune defense, foraging activity, and olfaction. In this last process, we evidenced regulation of chemosensory proteins and odorant-degrading enzymes, known to play a role in the dynamics and the sensitivity of the olfactory receptor neuron response. Our results identify new elements in the cascade of olfactory neuron modulation, in addition to insulin, GABA, and short neuropeptide F signaling. Abstract Starvation is frequently encountered by animals under fluctuating food conditions in nature, and response to it is vital for life span. Many studies have investigated the behavioral and physiological responses to starvation. In particular, starvation is known to induce changes in olfactory behaviors and olfactory sensitivity to food odorants, but the underlying mechanisms are not well understood. Here, we investigated the transcriptional changes induced by starvation in the chemosensory tissues of the caterpillar Spodoptera littoralis, using Illumina RNA sequencing. Gene expression profiling revealed 81 regulated transcripts associated with several biological processes, such as glucose metabolism, immune defense, response to stress, foraging activity, and olfaction. Focusing on the olfactory process, we observed changes in transcripts encoding proteins putatively involved in the peri-receptor events, namely, chemosensory proteins and odorant-degrading enzymes. Such modulation of their expression may drive fluctuations in the dynamics and the sensitivity of the olfactory receptor neuron response. In combination with the enhanced presynaptic activity mediated via the short neuropeptide F expressed during fasting periods, this could explain an enhanced olfactory detection process. Our observations suggest that a coordinated transcriptional response of peripheral chemosensory organs participates in the regulation of olfactory signal reception and olfactory-driven behaviors upon starvation.
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Affiliation(s)
- Erwan Poivet
- Institute of Ecology and Environmental Sciences of Paris, INRAE, Sorbonne Université, CNRS, IRD, UPEC, Université de Paris, 78000 Versailles, France; (E.P.); (A.G.); (N.M.); (C.M.)
| | - Aurore Gallot
- Institute of Ecology and Environmental Sciences of Paris, INRAE, Sorbonne Université, CNRS, IRD, UPEC, Université de Paris, 78000 Versailles, France; (E.P.); (A.G.); (N.M.); (C.M.)
| | - Nicolas Montagné
- Institute of Ecology and Environmental Sciences of Paris, INRAE, Sorbonne Université, CNRS, IRD, UPEC, Université de Paris, 78000 Versailles, France; (E.P.); (A.G.); (N.M.); (C.M.)
| | - Pavel Senin
- IRISA, INRIA, CNRS, Université de Rennes, 35000 Rennes, France; (P.S.); (F.L.)
| | - Christelle Monsempès
- Institute of Ecology and Environmental Sciences of Paris, INRAE, Sorbonne Université, CNRS, IRD, UPEC, Université de Paris, 78000 Versailles, France; (E.P.); (A.G.); (N.M.); (C.M.)
| | - Fabrice Legeai
- IRISA, INRIA, CNRS, Université de Rennes, 35000 Rennes, France; (P.S.); (F.L.)
- IGEPP, INRAE, Institut Agro, Université de Rennes, 35000 Rennes, France
| | - Emmanuelle Jacquin-Joly
- Institute of Ecology and Environmental Sciences of Paris, INRAE, Sorbonne Université, CNRS, IRD, UPEC, Université de Paris, 78000 Versailles, France; (E.P.); (A.G.); (N.M.); (C.M.)
- Correspondence:
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20
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Schlegel P, Bates AS, Stürner T, Jagannathan SR, Drummond N, Hsu J, Serratosa Capdevila L, Javier A, Marin EC, Barth-Maron A, Tamimi IFM, Li F, Rubin GM, Plaza SM, Costa M, Jefferis GSXE. Information flow, cell types and stereotypy in a full olfactory connectome. eLife 2021; 10:e66018. [PMID: 34032214 PMCID: PMC8298098 DOI: 10.7554/elife.66018] [Citation(s) in RCA: 60] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Accepted: 05/24/2021] [Indexed: 12/19/2022] Open
Abstract
The hemibrain connectome provides large-scale connectivity and morphology information for the majority of the central brain of Drosophila melanogaster. Using this data set, we provide a complete description of the Drosophila olfactory system, covering all first, second and lateral horn-associated third-order neurons. We develop a generally applicable strategy to extract information flow and layered organisation from connectome graphs, mapping olfactory input to descending interneurons. This identifies a range of motifs including highly lateralised circuits in the antennal lobe and patterns of convergence downstream of the mushroom body and lateral horn. Leveraging a second data set we provide a first quantitative assessment of inter- versus intra-individual stereotypy. Comparing neurons across two brains (three hemispheres) reveals striking similarity in neuronal morphology across brains. Connectivity correlates with morphology and neurons of the same morphological type show similar connection variability within the same brain as across two brains.
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Affiliation(s)
- Philipp Schlegel
- Neurobiology Division, MRC Laboratory of Molecular BiologyCambridgeUnited Kingdom
- Department of Zoology, University of CambridgeCambridgeUnited Kingdom
| | | | - Tomke Stürner
- Department of Zoology, University of CambridgeCambridgeUnited Kingdom
| | | | - Nikolas Drummond
- Department of Zoology, University of CambridgeCambridgeUnited Kingdom
| | - Joseph Hsu
- Department of Zoology, University of CambridgeCambridgeUnited Kingdom
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | | | - Alexandre Javier
- Department of Zoology, University of CambridgeCambridgeUnited Kingdom
| | - Elizabeth C Marin
- Department of Zoology, University of CambridgeCambridgeUnited Kingdom
| | - Asa Barth-Maron
- Department of Neurobiology, Harvard Medical SchoolBostonUnited States
| | - Imaan FM Tamimi
- Department of Zoology, University of CambridgeCambridgeUnited Kingdom
| | - Feng Li
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Gerald M Rubin
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Stephen M Plaza
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Marta Costa
- Department of Zoology, University of CambridgeCambridgeUnited Kingdom
| | - Gregory S X E Jefferis
- Neurobiology Division, MRC Laboratory of Molecular BiologyCambridgeUnited Kingdom
- Department of Zoology, University of CambridgeCambridgeUnited Kingdom
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21
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Üçpunar HK, Grunwald Kadow IC. Flies Avoid Current Atmospheric CO 2 Concentrations. Front Physiol 2021; 12:646401. [PMID: 33927640 PMCID: PMC8076854 DOI: 10.3389/fphys.2021.646401] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Accepted: 03/22/2021] [Indexed: 11/23/2022] Open
Abstract
CO2 differs from most other odors by being ubiquitously present in the air animals inhale. CO2 levels of the atmosphere, however, are subject to change. Depending on the landscape, temperature, and time of the year, CO2 levels can change even on shortest time scales. In addition, since the 18th century the CO2 baseline keeps increasing due to the intensive fossil fuel usage. However, we do not know whether this change is significant for animals, and if yes whether and how animals adapt to this change. Most insects possess olfactory receptors to detect the gaseous molecule, and CO2 is one of the key odorants for insects such as the vinegar fly Drosophila melanogaster to find food sources and to warn con-specifics. So far, CO2 and its sensory system have been studied in the context of rotting fruit and other CO2-emitting sources to investigate flies’ response to significantly elevated levels of CO2. However, it has not been addressed whether flies detect and potentially react to atmospheric levels of CO2. By using behavioral experiments, here we show that flies can detect atmospheric CO2 concentrations and, if given the choice, prefer air with sub-atmospheric levels of the molecule. Blocking the synaptic release from CO2 receptor neurons abolishes this choice. Based on electrophysiological recordings, we hypothesize that CO2 receptors, similar to ambient temperature receptors, actively sample environmental CO2 concentrations close to atmospheric levels. Based on recent findings and our data, we hypothesize that Gr-dependent CO2 receptors do not primarily serve as a cue detector to find food sources or avoid danger, instead they function as sensors for preferred environmental conditions.
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Affiliation(s)
- Habibe K Üçpunar
- Department of Physiology, School of Medicine, Ankara Medipol University, Ankara, Turkey
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22
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Muria A, Musso PY, Durrieu M, Portugal FR, Ronsin B, Gordon MD, Jeanson R, Isabel G. Social facilitation of long-lasting memory is mediated by CO 2 in Drosophila. Curr Biol 2021; 31:2065-2074.e5. [PMID: 33740428 DOI: 10.1016/j.cub.2021.02.044] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 12/22/2020] [Accepted: 02/17/2021] [Indexed: 01/05/2023]
Abstract
How social interactions influence cognition is a fundamental question, yet rarely addressed at the neurobiological level. It is well established that the presence of conspecifics affects learning and memory performance, but the neural basis of this process has only recently begun to be investigated. In the fruit fly Drosophila melanogaster, the presence of other flies improves retrieval of a long-lasting olfactory memory. Here, we demonstrate that this is a composite memory composed of two distinct elements. One is an individual memory that depends on outputs from the α'β' Kenyon cells (KCs) of the mushroom bodies (MBs), the memory center in the insect brain. The other is a group memory requiring output from the αβ KCs, a distinct sub-part of the MBs. We show that social facilitation of memory increases with group size and is triggered by CO2 released by group members. Among the different known neurons carrying CO2 information in the brain, we establish that the bilateral ventral projection neuron (biVPN), which projects onto the MBs, is necessary for social facilitation. Moreover, we demonstrate that CO2-evoked memory engages a serotoninergic pathway involving the dorsal-paired medial (DPM) neurons, revealing a new role for this pair of serotonergic neurons. Overall, we identified both the sensorial cue and the neural circuit (biVPN>αβ>DPM>αβ) governing social facilitation of memory in flies. This study provides demonstration that being in a group recruits the expression of a cryptic memory and that variations in CO2 concentration can affect cognitive processes in insects.
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Affiliation(s)
- Aurélie Muria
- Centre de Recherches sur la Cognition Animale (CRCA), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 118 route de Narbonne, Bat 4R4, 31062 Toulouse Cedex 9, France
| | - Pierre-Yves Musso
- Centre de Recherches sur la Cognition Animale (CRCA), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 118 route de Narbonne, Bat 4R4, 31062 Toulouse Cedex 9, France; Department of Zoology, Life Sciences Institute, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Matthias Durrieu
- Centre de Recherches sur la Cognition Animale (CRCA), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 118 route de Narbonne, Bat 4R4, 31062 Toulouse Cedex 9, France
| | - Felipe Ramon Portugal
- Laboratoire Évolution et Diversité Biologique (EDB UMR 5174), Université de Toulouse, CNRS, IRD, 118 route de Narbonne, Bat 4R1, 31062 Toulouse Cedex 9, France; Ecole Nationale Supérieure Formation de l'Enseignement Agricole, Castanet-Tolosan, France
| | - Brice Ronsin
- CBI, Université de Toulouse, CNRS, UPS, 118 route de Narbonne, Bat 4R4, 31062 Toulouse Cedex 9, France
| | - Michael D Gordon
- Department of Zoology, Life Sciences Institute, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Raphaël Jeanson
- Centre de Recherches sur la Cognition Animale (CRCA), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 118 route de Narbonne, Bat 4R4, 31062 Toulouse Cedex 9, France
| | - Guillaume Isabel
- Centre de Recherches sur la Cognition Animale (CRCA), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 118 route de Narbonne, Bat 4R4, 31062 Toulouse Cedex 9, France.
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23
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Tataridas-Pallas N, Thompson MA, Howard A, Brown I, Ezcurra M, Wu Z, Silva IG, Saunter CD, Kuerten T, Weinkove D, Blackwell TK, Tullet JMA. Neuronal SKN-1B modulates nutritional signalling pathways and mitochondrial networks to control satiety. PLoS Genet 2021; 17:e1009358. [PMID: 33661901 PMCID: PMC7932105 DOI: 10.1371/journal.pgen.1009358] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Accepted: 01/17/2021] [Indexed: 12/14/2022] Open
Abstract
The feeling of hunger or satiety results from integration of the sensory nervous system with other physiological and metabolic cues. This regulates food intake, maintains homeostasis and prevents disease. In C. elegans, chemosensory neurons sense food and relay information to the rest of the animal via hormones to control food-related behaviour and physiology. Here we identify a new component of this system, SKN-1B which acts as a central food-responsive node, ultimately controlling satiety and metabolic homeostasis. SKN-1B, an ortholog of mammalian NF-E2 related transcription factors (Nrfs), has previously been implicated with metabolism, respiration and the increased lifespan incurred by dietary restriction. Here we show that SKN-1B acts in two hypothalamus-like ASI neurons to sense food, communicate nutritional status to the organism, and control satiety and exploratory behaviours. This is achieved by SKN-1B modulating endocrine signalling pathways (IIS and TGF-β), and by promoting a robust mitochondrial network. Our data suggest a food-sensing and satiety role for mammalian Nrf proteins. Deciding when and how much to eat is important for maintaining health and preventing disease. It requires an intricate molecular level of communication between our nervous, physiological, and metabolic systems. These signals stimulate food intake, and afterwards the feeling of satiety which makes us stop eating. We have studied these phenomena using the simple nematode worm C. elegans which has a fully mapped nervous system and quantifiable food-related behaviours. In C. elegans, chemosensory neurons sense food and communicate this to the rest of the animal via hormones to control food-related behaviour and associated physiological changes. Here we identify a new central node of this system, the C. elegans gene SKN-1B, which acts in two sensory neurons to sense food, communicate food-status to the rest of the worm, and control satiety and exploratory behaviours. It does this by altering hormonal signalling (Insulin and Transforming Growth Factor-β), and by promoting a strong mitochondrial network. The mammalian equivalents of SKN-1B are the NF-E2 related transcription factors (Nrfs), which have previously been implicated with metabolism and respiration. Our data suggest a new food-sensing and satiety role for mammalian Nrf proteins.
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Affiliation(s)
| | | | - Alexander Howard
- School of Biosciences, University of Kent, Canterbury, United Kingdom
| | - Ian Brown
- School of Biosciences, University of Kent, Canterbury, United Kingdom
| | - Marina Ezcurra
- School of Biosciences, University of Kent, Canterbury, United Kingdom
| | - Ziyun Wu
- Joslin Diabetes Center, One Joslin Place, Boston, Massachusetts, United States of America
| | | | | | - Timo Kuerten
- School of Biosciences, University of Kent, Canterbury, United Kingdom
| | - David Weinkove
- Magnitude Biosciences Ltd, NETPark Plexus, Sedgefield, United Kingdom
| | - T. Keith Blackwell
- Joslin Diabetes Center, One Joslin Place, Boston, Massachusetts, United States of America
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24
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Dopamine modulation of sensory processing and adaptive behavior in flies. Cell Tissue Res 2021; 383:207-225. [PMID: 33515291 PMCID: PMC7873103 DOI: 10.1007/s00441-020-03371-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Accepted: 11/26/2020] [Indexed: 12/31/2022]
Abstract
Behavioral flexibility for appropriate action selection is an advantage when animals are faced with decisions that will determine their survival or death. In order to arrive at the right decision, animals evaluate information from their external environment, internal state, and past experiences. How these different signals are integrated and modulated in the brain, and how context- and state-dependent behavioral decisions are controlled are poorly understood questions. Studying the molecules that help convey and integrate such information in neural circuits is an important way to approach these questions. Many years of work in different model organisms have shown that dopamine is a critical neuromodulator for (reward based) associative learning. However, recent findings in vertebrates and invertebrates have demonstrated the complexity and heterogeneity of dopaminergic neuron populations and their functional implications in many adaptive behaviors important for survival. For example, dopaminergic neurons can integrate external sensory information, internal and behavioral states, and learned experience in the decision making circuitry. Several recent advances in methodologies and the availability of a synaptic level connectome of the whole-brain circuitry of Drosophila melanogaster make the fly an attractive system to study the roles of dopamine in decision making and state-dependent behavior. In particular, a learning and memory center—the mushroom body—is richly innervated by dopaminergic neurons that enable it to integrate multi-modal information according to state and context, and to modulate decision-making and behavior.
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25
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Abstract
The olfactory system translates chemical signals into neuronal signals that inform behavioral decisions of the animal. Odors are cues for source identity, but if monitored long enough, they can also be used to localize the source. Odor representations should therefore be robust to changing conditions and flexible in order to drive an appropriate behavior. In this review, we aim at discussing the main computations that allow robust and flexible encoding of odor information in the olfactory neural pathway.
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26
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Neuronal architecture of the second-order CO 2 pathway in the brain of a noctuid moth. Sci Rep 2020; 10:19838. [PMID: 33199810 PMCID: PMC7669840 DOI: 10.1038/s41598-020-76918-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 11/04/2020] [Indexed: 12/17/2022] Open
Abstract
Many insects possess the ability to detect fine fluctuations in the environmental CO2 concentration. In herbivorous species, plant-emitted CO2, in combination with other sensory cues, affect many behaviors including foraging and oviposition. In contrast to the comprehensive knowledge obtained on the insect olfactory pathway in recent years, we still know little about the central CO2 system. By utilizing intracellular labeling and mass staining, we report the neuroanatomy of projection neurons connected with the CO2 sensitive antennal-lobe glomerulus, the labial pit organ glomerulus (LPOG), in the noctuid moth, Helicoverpa armigera. We identified 15 individual LPOG projection neurons passing along different tracts. Most of these uniglomerular neurons terminated in the lateral horn, a previously well-described target area of plant-odor projection neurons originating from the numerous ordinary antennal-lobe glomeruli. The other higher-order processing area for odor information, the calyces, on the other hand, was weakly innervated by the LPOG neurons. The overlapping LPOG terminals in the lateral horn, which is considered important for innate behavior in insects, suggests the biological importance of integrating the CO2 input with plant odor information while the weak innervation of the calyces indicates the insignificance of this ubiquitous cue for learning mechanisms.
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27
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Bechtolsheim F, Oehme F, Weitz J, Oppermann N, Reissfelder C, Mees ST, Yang C. The Hunger Games: Laparoscopic Performance in Novice Surgeons is Not Altered by Food Deprivation but Influenced by the Degree of Appetite - A Randomized Controlled Trial. JOURNAL OF SURGICAL EDUCATION 2020; 77:1236-1243. [PMID: 32532700 DOI: 10.1016/j.jsurg.2020.03.029] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Revised: 02/27/2020] [Accepted: 03/31/2020] [Indexed: 06/11/2023]
Abstract
OBJECTIVES Food deprivation is a common condition for visceral surgeons and especially laparoscopic approaches require high levels of concentration. The current literature does not provide adequate answers whether intraoperative breaks, especially food intake, might influence the quality of the surgical skills. Thus, the primary aim of this trial was to analyze the influence of food deprivation on the laparoscopic performance. DESIGN SETTING AND PARTICIPANTS 37 laparoscopic novices participated from 10/2017 to 04/2018 in this single center, prospective-randomized trial and were trained during laparoscopic training sessions until they reached a predefined level of proficiency. Subsequently, participants were randomized into 3 different groups: food deprivation of 8 hours, 4 hours, or carbohydrate loading directly prior to the laparoscopic exam. The exam comprised PEG-transfer, precise cutting, gallbladder resection and surgical knot. MAIN FINDINGS Completion time for PEG-transfer, precise cutting, gallbladder resection and surgical knot was 63s, 139s, 192s and 272s respectively. Participants starving for 8 hours performed 3 of 4 tasks more slowly whilst participants starving for 4 hours performed 3 of 4 tasks faster than the average. Analyzing self-reported level of appetite revealed: Students with an intermediate level were significantly faster (p <0.05) during complex procedures compared to participants that reported hunger prior to performing these tasks (192s vs. 307s). Additionally, hungry students had been more inaccurate during the surgical knot (p <0.05) whilst students with intermediate appetite level tend to be most accurate (p - value 0.012). CONCLUSIONS The subjective level of appetite rather than the absolute number of fasting hours influences the laparoscopic performance most. Thus, any extreme level of appetite may be avoided and surgeons may achieve the best performance when they have an intermediate level of appetite. In consequence, heavy meals may be omitted immediately prior to demanding laparoscopic procedures and surgeons may have access to mini-breaks and refreshers during major procedures.
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Affiliation(s)
- Felix Bechtolsheim
- Department for Visceral, Thoracic and Vascular Surgery, University Hospital Dresden, Dresden, Germany
| | - Florian Oehme
- Department for Visceral, Thoracic and Vascular Surgery, University Hospital Dresden, Dresden, Germany
| | - Juergen Weitz
- Department for Visceral, Thoracic and Vascular Surgery, University Hospital Dresden, Dresden, Germany
| | - Nadine Oppermann
- Department for Visceral, Thoracic and Vascular Surgery, University Hospital Dresden, Dresden, Germany
| | - Christoph Reissfelder
- Department for Visceral, Thoracic and Vascular Surgery, University Hospital Dresden, Dresden, Germany; Department of Surgery, University Mannheim, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Soeren T Mees
- Department for Visceral, Thoracic and Vascular Surgery, University Hospital Dresden, Dresden, Germany; Department of General, Visceral, and Thoracic Surgery, Municipal Hospital Dresden-Friedrichstadt, Dresden, Germany
| | - Cui Yang
- Department for Visceral, Thoracic and Vascular Surgery, University Hospital Dresden, Dresden, Germany; Department of Surgery, University Mannheim, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany.
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28
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Bates AS, Schlegel P, Roberts RJV, Drummond N, Tamimi IFM, Turnbull R, Zhao X, Marin EC, Popovici PD, Dhawan S, Jamasb A, Javier A, Serratosa Capdevila L, Li F, Rubin GM, Waddell S, Bock DD, Costa M, Jefferis GSXE. Complete Connectomic Reconstruction of Olfactory Projection Neurons in the Fly Brain. Curr Biol 2020; 30:3183-3199.e6. [PMID: 32619485 PMCID: PMC7443706 DOI: 10.1016/j.cub.2020.06.042] [Citation(s) in RCA: 79] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Revised: 05/07/2020] [Accepted: 06/12/2020] [Indexed: 12/21/2022]
Abstract
Nervous systems contain sensory neurons, local neurons, projection neurons, and motor neurons. To understand how these building blocks form whole circuits, we must distil these broad classes into neuronal cell types and describe their network connectivity. Using an electron micrograph dataset for an entire Drosophila melanogaster brain, we reconstruct the first complete inventory of olfactory projections connecting the antennal lobe, the insect analog of the mammalian olfactory bulb, to higher-order brain regions in an adult animal brain. We then connect this inventory to extant data in the literature, providing synaptic-resolution "holotypes" both for heavily investigated and previously unknown cell types. Projection neurons are approximately twice as numerous as reported by light level studies; cell types are stereotyped, but not identical, in cell and synapse numbers between brain hemispheres. The lateral horn, the insect analog of the mammalian cortical amygdala, is the main target for this olfactory information and has been shown to guide innate behavior. Here, we find new connectivity motifs, including axo-axonic connectivity between projection neurons, feedback, and lateral inhibition of these axons by a large population of neurons, and the convergence of different inputs, including non-olfactory inputs and memory-related feedback onto third-order olfactory neurons. These features are less prominent in the mushroom body calyx, the insect analog of the mammalian piriform cortex and a center for associative memory. Our work provides a complete neuroanatomical platform for future studies of the adult Drosophila olfactory system.
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Affiliation(s)
- Alexander S Bates
- Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge CB2 0QH, UK
| | - Philipp Schlegel
- Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge CB2 0QH, UK; Department of Zoology, University of Cambridge, Cambridge CB2 3EJ, UK
| | | | - Nikolas Drummond
- Department of Zoology, University of Cambridge, Cambridge CB2 3EJ, UK
| | - Imaan F M Tamimi
- Department of Zoology, University of Cambridge, Cambridge CB2 3EJ, UK
| | - Robert Turnbull
- Department of Zoology, University of Cambridge, Cambridge CB2 3EJ, UK
| | - Xincheng Zhao
- Department of Zoology, University of Cambridge, Cambridge CB2 3EJ, UK; Department of Entomology, College of Plant Protection, Henan Agricultural University, Zhengzhou 450002, China
| | - Elizabeth C Marin
- Department of Zoology, University of Cambridge, Cambridge CB2 3EJ, UK
| | - Patricia D Popovici
- Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge CB2 0QH, UK
| | - Serene Dhawan
- Department of Zoology, University of Cambridge, Cambridge CB2 3EJ, UK
| | - Arian Jamasb
- Department of Zoology, University of Cambridge, Cambridge CB2 3EJ, UK
| | - Alexandre Javier
- Department of Zoology, University of Cambridge, Cambridge CB2 3EJ, UK
| | | | - Feng Li
- 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
| | - Scott Waddell
- Centre for Neural Circuits and Behaviour, The University of Oxford, Oxford OX1 3SR, UK
| | - Davi D Bock
- Department of Neurological Sciences, Larner College of Medicine, University of Vermont, VT 05405, USA
| | - Marta Costa
- Department of Zoology, University of Cambridge, Cambridge CB2 3EJ, UK
| | - Gregory S X E Jefferis
- Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge CB2 0QH, UK; Department of Zoology, University of Cambridge, Cambridge CB2 3EJ, UK.
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29
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Lerner H, Rozenfeld E, Rozenman B, Huetteroth W, Parnas M. Differential Role for a Defined Lateral Horn Neuron Subset in Naïve Odor Valence in Drosophila. Sci Rep 2020; 10:6147. [PMID: 32273557 PMCID: PMC7145822 DOI: 10.1038/s41598-020-63169-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Accepted: 03/26/2020] [Indexed: 11/09/2022] Open
Abstract
Value coding of external stimuli in general, and odor valence in particular, is crucial for survival. In flies, odor valence is thought to be coded by two types of neurons: mushroom body output neurons (MBONs) and lateral horn (LH) neurons. MBONs are classified as neurons that promote either attraction or aversion, but not both, and they are dynamically activated by upstream neurons. This dynamic activation updates the valence values. In contrast, LH neurons receive scaled, but non-dynamic, input from their upstream neurons. It remains unclear how such a non-dynamic system generates differential valence values. Recently, PD2a1/b1 LH neurons were demonstrated to promote approach behavior at low odor concentration in starved flies. Here, we demonstrate that at high odor concentrations, these same neurons contribute to avoidance in satiated flies. The contribution of PD2a1/b1 LH neurons to aversion is context dependent. It is diminished in starved flies, although PD2a1/b1 neural activity remains unchanged, and at lower odor concentration. In addition, PD2a1/b1 aversive effect develops over time. Thus, our results indicate that, even though PD2a1/b1 LH neurons transmit hard-wired output, their effect on valence can change. Taken together, we suggest that the valence model described for MBONs does not hold for LH neurons.
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Affiliation(s)
- Hadas Lerner
- Department of Physiology and Pharmacology, Sackler School of Medicine, Tel Aviv University, Tel Aviv, 69978, Israel
| | - Eyal Rozenfeld
- Department of Physiology and Pharmacology, Sackler School of Medicine, Tel Aviv University, Tel Aviv, 69978, Israel.,Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, 69978, Israel
| | - Bar Rozenman
- Department of Physiology and Pharmacology, Sackler School of Medicine, Tel Aviv University, Tel Aviv, 69978, Israel
| | - Wolf Huetteroth
- Institute for Biology, University of Leipzig, Talstraße 33, 04103, Leipzig, Germany
| | - Moshe Parnas
- Department of Physiology and Pharmacology, Sackler School of Medicine, Tel Aviv University, Tel Aviv, 69978, Israel. .,Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, 69978, Israel.
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30
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Serotonin transporter dependent modulation of food-seeking behavior. PLoS One 2020; 15:e0227554. [PMID: 31978073 PMCID: PMC6980608 DOI: 10.1371/journal.pone.0227554] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Accepted: 12/20/2019] [Indexed: 11/28/2022] Open
Abstract
The olfactory pathway integrates the odor information required to generate correct behavioral responses. To address how changes of serotonin signaling in two contralaterally projecting, serotonin-immunoreactive deutocerebral neurons impacts key odorant attraction in Drosophila melanogaster, we selectively alter serotonin signaling using the serotonin transporter with mutated serotonin binding sites in these neurons and analyzed the consequence on odorant-guided food seeking. The expression of the mutated serotonin transporter selectively changed the odorant attraction in an odorant-specific manner. The shift in attraction was not influenced by more up-stream serotonergic mechanisms mediating behavioral inhibition. The expression of the mutated serotonin transporter in CSD neurons did not influence other behaviors associated with food seeking such as olfactory learning and memory or food consumption. We provide evidence that the change in the attraction by serotonin transporter function might be achieved by increased serotonin signaling and by different serotonin receptors. The 5-HT1B receptor positively regulated the attraction to low and negatively regulated the attraction to high concentrations of acetic acid. In contrast, 5-HT1A and 5-HT2A receptors negatively regulated the attraction in projection neurons to high acetic acid concentrations. These results provide insights into how serotonin signaling in two serotonergic neurons selectively regulates the behavioral response to key odorants during food seeking.
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31
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Sayin S, De Backer JF, Siju KP, Wosniack ME, Lewis LP, Frisch LM, Gansen B, Schlegel P, Edmondson-Stait A, Sharifi N, Fisher CB, Calle-Schuler SA, Lauritzen JS, Bock DD, Costa M, Jefferis GSXE, Gjorgjieva J, Grunwald Kadow IC. A Neural Circuit Arbitrates between Persistence and Withdrawal in Hungry Drosophila. Neuron 2019; 104:544-558.e6. [PMID: 31471123 PMCID: PMC6839618 DOI: 10.1016/j.neuron.2019.07.028] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 06/09/2019] [Accepted: 07/22/2019] [Indexed: 01/24/2023]
Abstract
In pursuit of food, hungry animals mobilize significant energy resources and overcome exhaustion and fear. How need and motivation control the decision to continue or change behavior is not understood. Using a single fly treadmill, we show that hungry flies persistently track a food odor and increase their effort over repeated trials in the absence of reward suggesting that need dominates negative experience. We further show that odor tracking is regulated by two mushroom body output neurons (MBONs) connecting the MB to the lateral horn. These MBONs, together with dopaminergic neurons and Dop1R2 signaling, control behavioral persistence. Conversely, an octopaminergic neuron, VPM4, which directly innervates one of the MBONs, acts as a brake on odor tracking by connecting feeding and olfaction. Together, our data suggest a function for the MB in internal state-dependent expression of behavior that can be suppressed by external inputs conveying a competing behavioral drive. Hunger motivates persistent food odor tracking even without reward Two synaptically connected MBONs, -γ1pedc>αβ and -α2sc, regulate odor tracking Octopamine neurons connect feeding and counteract MBON and odor tracking Dopaminergic neurons and Dop1R2 signaling promote persistent tracking
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Affiliation(s)
- Sercan Sayin
- Technical University of Munich, School of Life Sciences, 85354 Freising, Germany
| | | | - K P Siju
- Technical University of Munich, School of Life Sciences, 85354 Freising, Germany
| | - Marina E Wosniack
- Technical University of Munich, School of Life Sciences, 85354 Freising, Germany; Max Planck Institute for Brain Research, Computation in Neural Circuits Group, 60438 Frankfurt, Germany
| | - Laurence P Lewis
- Max Planck Institute of Neurobiology, Chemosensory Coding Group, 82152 Martinsried, Germany
| | - Lisa-Marie Frisch
- Technical University of Munich, School of Life Sciences, 85354 Freising, Germany
| | - Benedikt Gansen
- Technical University of Munich, School of Life Sciences, 85354 Freising, Germany
| | - Philipp Schlegel
- Drosophila Connectomics Group, Department of Zoology, University of Cambridge, Cambridge CB2 3EJ, UK
| | - Amelia Edmondson-Stait
- Drosophila Connectomics Group, Department of Zoology, University of Cambridge, Cambridge CB2 3EJ, UK
| | | | | | | | | | - Davi D Bock
- HHMI Janelia Research Campus, Ashburn, VA 20147, USA
| | - Marta Costa
- Drosophila Connectomics Group, Department of Zoology, University of Cambridge, Cambridge CB2 3EJ, UK
| | - Gregory S X E Jefferis
- Drosophila Connectomics Group, Department of Zoology, University of Cambridge, Cambridge CB2 3EJ, UK; Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge CB2 0QH, UK
| | - Julijana Gjorgjieva
- Technical University of Munich, School of Life Sciences, 85354 Freising, Germany; Max Planck Institute for Brain Research, Computation in Neural Circuits Group, 60438 Frankfurt, Germany
| | - Ilona C Grunwald Kadow
- Technical University of Munich, School of Life Sciences, 85354 Freising, Germany; ZIEL - Institute for food and health, 85354 Freising, Germany; Max Planck Institute of Neurobiology, Chemosensory Coding Group, 82152 Martinsried, Germany.
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32
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Bielopolski N, Amin H, Apostolopoulou AA, Rozenfeld E, Lerner H, Huetteroth W, Lin AC, Parnas M. Inhibitory muscarinic acetylcholine receptors enhance aversive olfactory learning in adult Drosophila. eLife 2019; 8:48264. [PMID: 31215865 PMCID: PMC6641838 DOI: 10.7554/elife.48264] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 06/18/2019] [Indexed: 11/13/2022] Open
Abstract
Olfactory associative learning in Drosophila is mediated by synaptic plasticity between the Kenyon cells of the mushroom body and their output neurons. Both Kenyon cells and their inputs from projection neurons are cholinergic, yet little is known about the physiological function of muscarinic acetylcholine receptors in learning in adult flies. Here, we show that aversive olfactory learning in adult flies requires type A muscarinic acetylcholine receptors (mAChR-A), particularly in the gamma subtype of Kenyon cells. mAChR-A inhibits odor responses and is localized in Kenyon cell dendrites. Moreover, mAChR-A knockdown impairs the learning-associated depression of odor responses in a mushroom body output neuron. Our results suggest that mAChR-A function in Kenyon cell dendrites is required for synaptic plasticity between Kenyon cells and their output neurons.
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Affiliation(s)
- Noa Bielopolski
- Department of Physiology and Pharmacology, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Hoger Amin
- Department of Biomedical Science, University of Sheffield, Sheffield, United Kingdom
| | | | - Eyal Rozenfeld
- Department of Physiology and Pharmacology, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Hadas Lerner
- Department of Physiology and Pharmacology, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Wolf Huetteroth
- Institute for Biology, University of Leipzig, Leipzig, Germany
| | - Andrew C Lin
- Department of Biomedical Science, University of Sheffield, Sheffield, United Kingdom
| | - Moshe Parnas
- Department of Physiology and Pharmacology, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.,Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
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33
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Bui M, Shyong J, Lutz EK, Yang T, Li M, Truong K, Arvidson R, Buchman A, Riffell JA, Akbari OS. Live calcium imaging of Aedes aegypti neuronal tissues reveals differential importance of chemosensory systems for life-history-specific foraging strategies. BMC Neurosci 2019; 20:27. [PMID: 31208328 PMCID: PMC6580577 DOI: 10.1186/s12868-019-0511-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Accepted: 06/10/2019] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND The mosquito Aedes aegypti has a wide variety of sensory pathways that have supported its success as a species as well as a highly competent vector of numerous debilitating infectious pathogens. Investigations into mosquito sensory systems and their effects on behavior are valuable resources for the advancement of mosquito control strategies. Numerous studies have elucidated key aspects of mosquito sensory systems, however there remains critical gaps within the field. In particular, compared to that of the adult form, there has been a lack of studies directed towards the immature life stages. Additionally, although numerous studies have pinpointed specific sensory receptors as well as responding motor outputs, there has been a lack of studies able to monitor both concurrently. RESULTS To begin filling aforementioned gaps, here we engineered Ae. aegypti to ubiquitously express a genetically encoded calcium indicator, GCaMP6s. Using this strain, combined with advanced microscopy, we simultaneously measured live stimulus-evoked calcium responses in both neuronal and muscle cells with a wide spatial range and resolution. CONCLUSIONS By coupling in vivo live calcium imaging with behavioral assays we were able to gain functional insights into how stimulus-evoked neural and muscle activities are represented, modulated, and transformed in mosquito larvae enabling us to elucidate mosquito sensorimotor properties important for life-history-specific foraging strategies.
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Affiliation(s)
- Michelle Bui
- Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, CA 92093 USA
| | - Jennifer Shyong
- Department of Entomology and Riverside Center for Disease Vector Research, Institute for Integrative Genome Biology, University of California, Riverside, Riverside, CA 92521 USA
| | - Eleanor K. Lutz
- Department of Biology, University of Washington, Seattle, WA 98195 USA
| | - Ting Yang
- Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, CA 92093 USA
| | - Ming Li
- Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, CA 92093 USA
| | - Kenneth Truong
- Department of Entomology and Riverside Center for Disease Vector Research, Institute for Integrative Genome Biology, University of California, Riverside, Riverside, CA 92521 USA
| | - Ryan Arvidson
- Department of Entomology and Riverside Center for Disease Vector Research, Institute for Integrative Genome Biology, University of California, Riverside, Riverside, CA 92521 USA
| | - Anna Buchman
- Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, CA 92093 USA
| | | | - Omar S. Akbari
- Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, CA 92093 USA
- Tata Institute for Genetics and Society, University of California, San Diego, La Jolla, CA 92093 USA
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34
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Reisenman CE, Scott K. Food-derived volatiles enhance consumption in Drosophila melanogaster. ACTA ACUST UNITED AC 2019; 222:jeb.202762. [PMID: 31085598 DOI: 10.1242/jeb.202762] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 05/02/2019] [Indexed: 11/20/2022]
Abstract
Insects use multiple sensory modalities when searching for and accepting a food source, in particular odor and taste cues. Food-derived odorants are generally involved in mediating long- and short-range attraction. Taste cues, in contrast, act directly by contact with the food source, promoting the ingestion of nutritious food and the avoidance of toxic substances. It is possible, however, that insects integrate information from these sensory modalities during the process of feeding itself. Here, using a simple feeding assay, we investigated whether odors modulate food consumption in the fruit fly Drosophila melanogaster We found that the presence of both single food-derived odorants and complex odor mixtures enhanced consumption of an appetitive food. Feeding enhancement depended on the concentration and the chemical identity of the odorant. Volatile cues alone were sufficient to mediate this effect, as feeding was also increased when animals were prevented from contacting the odor source. Both males and females, including virgin females, increased ingestion in the presence of food-derived volatiles. Moreover, the presence of food-derived odorants significantly increased the consumption of food mixtures containing aversive bitter compounds, suggesting that flies integrate diverse olfactory and gustatory cues to guide feeding decisions, including situations in which animals are confronted with stimuli of opposite valence. Overall, these results show that food-derived olfactory cues directly modulate feeding in D. melanogaster, enhancing ingestion.
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Affiliation(s)
- Carolina E Reisenman
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, CA 94720, USA .,Essig Museum of Entomology, University of California Berkeley, Berkeley, CA 94720, USA
| | - Kristin Scott
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, CA 94720, USA.,Helen Wills Neuroscience Institute, University of California Berkeley, Berkeley, CA 94720, USA
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35
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Dolan MJ, Frechter S, Bates AS, Dan C, Huoviala P, Roberts RJV, Schlegel P, Dhawan S, Tabano R, Dionne H, Christoforou C, Close K, Sutcliffe B, Giuliani B, Li F, Costa M, Ihrke G, Meissner GW, Bock DD, Aso Y, Rubin GM, Jefferis GSXE. Neurogenetic dissection of the Drosophila lateral horn reveals major outputs, diverse behavioural functions, and interactions with the mushroom body. eLife 2019; 8:e43079. [PMID: 31112130 PMCID: PMC6529221 DOI: 10.7554/elife.43079] [Citation(s) in RCA: 84] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Accepted: 02/07/2019] [Indexed: 01/26/2023] Open
Abstract
Animals exhibit innate behaviours to a variety of sensory stimuli including olfactory cues. In Drosophila, one higher olfactory centre, the lateral horn (LH), is implicated in innate behaviour. However, our structural and functional understanding of the LH is scant, in large part due to a lack of sparse neurogenetic tools for this region. We generate a collection of split-GAL4 driver lines providing genetic access to 82 LH cell types. We use these to create an anatomical and neurotransmitter map of the LH and link this to EM connectomics data. We find ~30% of LH projections converge with outputs from the mushroom body, site of olfactory learning and memory. Using optogenetic activation, we identify LH cell types that drive changes in valence behavior or specific locomotor programs. In summary, we have generated a resource for manipulating and mapping LH neurons, providing new insights into the circuit basis of innate and learned olfactory behavior.
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Affiliation(s)
- Michael-John Dolan
- Howard Hughes Medical Institute, Janelia Research CampusAshburnUnited States
- Division of NeurobiologyMRC Laboratory of Molecular BiologyCambridgeUnited Kingdom
| | - Shahar Frechter
- Division of NeurobiologyMRC Laboratory of Molecular BiologyCambridgeUnited Kingdom
| | | | - Chuntao Dan
- Howard Hughes Medical Institute, Janelia Research CampusAshburnUnited States
| | - Paavo Huoviala
- Division of NeurobiologyMRC Laboratory of Molecular BiologyCambridgeUnited Kingdom
| | | | - Philipp Schlegel
- Division of NeurobiologyMRC Laboratory of Molecular BiologyCambridgeUnited Kingdom
- Department of ZoologyUniversity of CambridgeCambridgeUnited Kingdom
| | - Serene Dhawan
- Division of NeurobiologyMRC Laboratory of Molecular BiologyCambridgeUnited Kingdom
- Department of ZoologyUniversity of CambridgeCambridgeUnited Kingdom
| | - Remy Tabano
- Howard Hughes Medical Institute, Janelia Research CampusAshburnUnited States
| | - Heather Dionne
- Howard Hughes Medical Institute, Janelia Research CampusAshburnUnited States
| | | | - Kari Close
- Howard Hughes Medical Institute, Janelia Research CampusAshburnUnited States
| | - Ben Sutcliffe
- Division of NeurobiologyMRC Laboratory of Molecular BiologyCambridgeUnited Kingdom
| | - Bianca Giuliani
- Howard Hughes Medical Institute, Janelia Research CampusAshburnUnited States
| | - Feng Li
- Howard Hughes Medical Institute, Janelia Research CampusAshburnUnited States
| | - Marta Costa
- Department of ZoologyUniversity of CambridgeCambridgeUnited Kingdom
| | - Gudrun Ihrke
- Howard Hughes Medical Institute, Janelia Research CampusAshburnUnited States
| | | | - Davi D Bock
- Howard Hughes Medical Institute, Janelia Research CampusAshburnUnited States
| | - Yoshinori Aso
- Howard Hughes Medical Institute, Janelia Research CampusAshburnUnited States
| | - Gerald M Rubin
- Howard Hughes Medical Institute, Janelia Research CampusAshburnUnited States
| | - Gregory SXE Jefferis
- Howard Hughes Medical Institute, Janelia Research CampusAshburnUnited States
- Division of NeurobiologyMRC Laboratory of Molecular BiologyCambridgeUnited Kingdom
- Department of ZoologyUniversity of CambridgeCambridgeUnited Kingdom
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36
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Frechter S, Bates AS, Tootoonian S, Dolan MJ, Manton J, Jamasb AR, Kohl J, Bock D, Jefferis G. Functional and anatomical specificity in a higher olfactory centre. eLife 2019; 8:44590. [PMID: 31112127 PMCID: PMC6550879 DOI: 10.7554/elife.44590] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 04/12/2019] [Indexed: 12/16/2022] Open
Abstract
Most sensory systems are organized into parallel neuronal pathways that process distinct aspects of incoming stimuli. In the insect olfactory system, second order projection neurons target both the mushroom body, required for learning, and the lateral horn (LH), proposed to mediate innate olfactory behavior. Mushroom body neurons form a sparse olfactory population code, which is not stereotyped across animals. In contrast, odor coding in the LH remains poorly understood. We combine genetic driver lines, anatomical and functional criteria to show that the Drosophila LH has ~1400 neurons and >165 cell types. Genetically labeled LHNs have stereotyped odor responses across animals and on average respond to three times more odors than single projection neurons. LHNs are better odor categorizers than projection neurons, likely due to stereotyped pooling of related inputs. Our results reveal some of the principles by which a higher processing area can extract innate behavioral significance from sensory stimuli.
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Affiliation(s)
- Shahar Frechter
- Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
| | | | - Sina Tootoonian
- Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom.,Department of Neuroscience, Physiology and Pharmacology, University College London, London, United Kingdom.,Neurophysiology of Behaviour Laboratory, The Francis Crick Institute, London, United Kingdom
| | - Michael-John Dolan
- Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom.,Janelia Research Campus, Howard Hughes Medical Institute, Chevy Chase, United States
| | - James Manton
- Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
| | | | - Johannes Kohl
- Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
| | - Davi Bock
- Janelia Research Campus, Howard Hughes Medical Institute, Chevy Chase, United States
| | - Gregory Jefferis
- Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom.,Department of Zoology, University of Cambridge, Cambridge, United Kingdom
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37
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Varela N, Gaspar M, Dias S, Vasconcelos ML. Avoidance response to CO2 in the lateral horn. PLoS Biol 2019; 17:e2006749. [PMID: 30653496 PMCID: PMC6336243 DOI: 10.1371/journal.pbio.2006749] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Accepted: 12/13/2018] [Indexed: 12/16/2022] Open
Abstract
In flies, the olfactory information is carried from the first relay in the brain, the antennal lobe, to the mushroom body (MB) and the lateral horn (LH). Olfactory associations are formed in the MB. The LH was ascribed a role in innate responses based on the stereotyped connectivity with the antennal lobe, stereotyped physiological responses to odors, and MB silencing experiments. Direct evidence for the functional role of the LH is still missing. Here, we investigate the behavioral role of the LH neurons (LHNs) directly, using the CO2 response as a paradigm. Our results show the involvement of the LH in innate responses. Specifically, we demonstrate that activity in two sets of neurons is required for the full behavioral response to CO2. Tests of the behavioral response to other odors indicate the neurons are selective to CO2 response. Using calcium imaging, we observe that the two sets of neurons respond to CO2 in a different manner. Using independent manipulation and recording of the two sets of neurons, we find that the one that projects to the superior intermediate protocerebrum (SIP) also outputs to the local neurons within the LH. The design of simultaneous output at the LH and the SIP, an output of the MB, allows for coordination between innate and learned responses.
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Affiliation(s)
- Nélia Varela
- Champalimaud Research, Champalimaud Centre for the Unknown, Lisbon, Portugal
| | - Miguel Gaspar
- Champalimaud Research, Champalimaud Centre for the Unknown, Lisbon, Portugal
| | - Sophie Dias
- Champalimaud Research, Champalimaud Centre for the Unknown, Lisbon, Portugal
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38
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Crossley M, Staras K, Kemenes G. A central control circuit for encoding perceived food value. SCIENCE ADVANCES 2018; 4:eaau9180. [PMID: 30474061 PMCID: PMC6248929 DOI: 10.1126/sciadv.aau9180] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 10/24/2018] [Indexed: 05/10/2023]
Abstract
Hunger state can substantially alter the perceived value of a stimulus, even to the extent that the same sensory cue can trigger antagonistic behaviors. How the nervous system uses these graded perceptual shifts to select between opposed motor patterns remains enigmatic. Here, we challenged food-deprived and satiated Lymnaea to choose between two mutually exclusive behaviors, ingestion or egestion, produced by the same feeding central pattern generator. Decoding the underlying neural circuit reveals that the activity of central dopaminergic interneurons defines hunger state and drives network reconfiguration, biasing satiated animals toward the rejection of stimuli deemed palatable by food-deprived ones. By blocking the action of these neurons, satiated animals can be reconfigured to exhibit a hungry animal phenotype. This centralized mechanism occurs in the complete absence of sensory retuning and generalizes across different sensory modalities, allowing food-deprived animals to increase their perception of food value in a stimulus-independent manner to maximize potential calorific intake.
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39
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Grunwald Kadow IC. State-dependent plasticity of innate behavior in fruit flies. Curr Opin Neurobiol 2018; 54:60-65. [PMID: 30219668 DOI: 10.1016/j.conb.2018.08.014] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Accepted: 08/28/2018] [Indexed: 01/27/2023]
Abstract
Behaviors are often categorized into innate or learned. Innate behaviors are thought to be genetically encoded and hardwired into the brain, while learned behavior is a product of the interaction between experience and the plasticity of synapses and neurons. Recent work in different models show that innate behavior, too, is plastic and depends on the current behavioral context and the internal state of an animal. Furthermore, these studies suggest that the neural circuits underpinning innate and learned behavior interact and even overlap. For instance, hunger modulates several innate behaviors relying in part on neural circuits required for learning and memory such as the mushroom body in the fruit fly. These new findings suggest that state-dependent innate behavior and learning rely on functionally and anatomically overlapping and shared neural circuits indicating a common evolutionary history.
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Affiliation(s)
- Ilona C Grunwald Kadow
- Technical University of Munich, School of Life Sciences, ZIEL, Liesel-Beckmann-Str. 4, 85354, Freising, Germany.
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40
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Androschuk A, He RX, Weber S, Rosenfelt C, Bolduc FV. Stress Odorant Sensory Response Dysfunction in Drosophila Fragile X Syndrome Mutants. Front Mol Neurosci 2018; 11:242. [PMID: 30135642 PMCID: PMC6092503 DOI: 10.3389/fnmol.2018.00242] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Accepted: 06/22/2018] [Indexed: 01/05/2023] Open
Abstract
Sensory processing dysfunction (SPD) is present in most patients with intellectual disability (ID) and autism spectrum disorder (ASD). Silencing expression of the Fragile X mental retardation 1 (FMR1) gene leads to Fragile X syndrome (FXS), the most common single gene cause of ID and ASD. Drosophila have a highly conserved FMR1 ortholog, dfmr1. dfmr1 mutants display cognitive and social defects reminiscent of symptoms seen in individuals with FXS. We utilized a robust behavioral assay for sensory processing of the Drosophila stress odorant (dSO) to gain a better understanding of the molecular basis of SPD in FXS. Here, we show that dfmr1 mutant flies present significant defects in dSO response. We found that dfmr1 expression in mushroom bodies is required for dSO processing. We also show that cyclic adenosine monophosphate (cAMP) signaling via PKA is activated after exposure to dSO and that several drugs regulating both cAMP and cyclic guanosine monophosphate (cGMP) levels significantly improved defects in dSO processing in dfmr1 mutant flies.
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Affiliation(s)
- Alaura Androschuk
- Department of Pediatrics, University of Alberta, Edmonton, AB, Canada
| | - Richard X He
- Department of Pediatrics, University of Alberta, Edmonton, AB, Canada
| | - Savannah Weber
- Department of Pediatrics, University of Alberta, Edmonton, AB, Canada
| | - Cory Rosenfelt
- Department of Pediatrics, University of Alberta, Edmonton, AB, Canada
| | - Francois V Bolduc
- Department of Pediatrics, University of Alberta, Edmonton, AB, Canada.,Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada.,Department of Medical Genetics, University of Alberta, Edmonton, AB, Canada
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41
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Vale R, Evans D, Branco T. A Behavioral Assay for Investigating the Role of Spatial Memory During Instinctive Defense in Mice. J Vis Exp 2018. [PMID: 30080198 PMCID: PMC6126525 DOI: 10.3791/56988] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Evolution has selected a repertoire of defensive behaviors that are essential for survival across all animal species. These behaviors are often stereotyped actions elicited in response to innately aversive sensory stimuli, but their success requires enough flexibility for adapting to different spatial environments, which can change rapidly. Here, we describe a behavioral assay to evaluate the influence of learned spatial knowledge on defensive behaviors in mice. We have adapted the widely used Barnes maze spatial memory assay to investigate how mice navigate to a shelter during escape responses to innately aversive sensory stimuli in a novel environment, and how they adapt to acute changes in the environment. This new assay is an ethological paradigm that does not require training and exploits the natural exploration patterns and navigation strategies in mice. We propose that the set of protocols described here are a powerful means of studying goal-directed behaviors and stimulus-triggered navigation, which should be of interest to both the fields of instinctive behaviors and spatial memory.
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Affiliation(s)
- Ruben Vale
- UCL Sainsbury Wellcome Centre for Neural Circuits and Behaviour; MRC Laboratory of Molecular Biology
| | - Dominic Evans
- UCL Sainsbury Wellcome Centre for Neural Circuits and Behaviour; MRC Laboratory of Molecular Biology
| | - Tiago Branco
- UCL Sainsbury Wellcome Centre for Neural Circuits and Behaviour; MRC Laboratory of Molecular Biology;
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42
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Marescotti M, Lagogiannis K, Webb B, Davies RW, Armstrong JD. Monitoring brain activity and behaviour in freely moving Drosophila larvae using bioluminescence. Sci Rep 2018; 8:9246. [PMID: 29915372 PMCID: PMC6006295 DOI: 10.1038/s41598-018-27043-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Accepted: 05/09/2018] [Indexed: 12/18/2022] Open
Abstract
We present a bioluminescence method, based on the calcium-reporter Aequorin (AEQ), that exploits targeted transgenic expression patterns to identify activity of specific neural groups in the larval Drosophila nervous system. We first refine, for intact but constrained larva, the choice of Aequorin transgene and method of delivery of the co-factor coelenterazine and assay the luminescence signal produced for different neural expression patterns and concentrations of co-factor, using standard photo-counting techniques. We then develop an apparatus that allows simultaneous measurement of this neural signal while video recording the crawling path of an unconstrained animal. The setup also enables delivery and measurement of an olfactory cue (CO2) and we demonstrate the ability to record synchronized changes in Kenyon cell activity and crawling speed caused by the stimulus. Our approach is thus shown to be an effective and affordable method for studying the neural basis of behavior in Drosophila larvae.
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Affiliation(s)
- Manuela Marescotti
- Brainwave-Discovery Ltd., Edinburgh, Scotland, UK. .,The University of Edinburgh, Edinburgh, Scotland, UK.
| | - Konstantinos Lagogiannis
- The University of Edinburgh, Edinburgh, Scotland, UK.,Centre Of Developmental Neuroscience, King's College London, London, UK
| | - Barbara Webb
- The University of Edinburgh, Edinburgh, Scotland, UK
| | - R Wayne Davies
- Brainwave-Discovery Ltd., Edinburgh, Scotland, UK.,The University of Edinburgh, Edinburgh, Scotland, UK
| | - J Douglas Armstrong
- Brainwave-Discovery Ltd., Edinburgh, Scotland, UK.,The University of Edinburgh, Edinburgh, Scotland, UK
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43
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Ohashi H, Sakai T. Leucokinin signaling regulates hunger-driven reduction of behavioral responses to noxious heat in Drosophila. Biochem Biophys Res Commun 2018; 499:221-226. [PMID: 29559237 DOI: 10.1016/j.bbrc.2018.03.132] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Accepted: 03/16/2018] [Indexed: 02/04/2023]
Abstract
In the fruitfly Drosophila melanogaster, hunger has a significant impact on its sensory systems and brain functions, and consequently modifies related behaviors. However, it remains unclarified whether hunger affects nociceptive behavioral responses to heat stimuli. In this study, we show that food deprivation reduces responses to noxious heat in wild-type flies. We further identified that the neuropeptide Leucokinin (Lk) and its receptor (Lkr) are essential for the reduction of responses to noxious heat. Temporal silencing of Lk-expressing neurons and a knockout mutation of Lkr generated using the CRISPR/Cas9 system inhibited the reduction of responses to noxious heat. Thus, our results reveal that hunger induces reduction of responses to noxious heat through the Lk/Lkr signaling pathway in Drosophila.
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Affiliation(s)
- Hirono Ohashi
- Department of Biological Sciences, Tokyo Metropolitan University, Hachioji, Tokyo, Japan
| | - Takaomi Sakai
- Department of Biological Sciences, Tokyo Metropolitan University, Hachioji, Tokyo, Japan.
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44
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Tsao CH, Chen CC, Lin CH, Yang HY, Lin S. Drosophila mushroom bodies integrate hunger and satiety signals to control innate food-seeking behavior. eLife 2018; 7:35264. [PMID: 29547121 PMCID: PMC5910021 DOI: 10.7554/elife.35264] [Citation(s) in RCA: 90] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Accepted: 03/15/2018] [Indexed: 12/28/2022] Open
Abstract
The fruit fly can evaluate its energy state and decide whether to pursue food-related cues. Here, we reveal that the mushroom body (MB) integrates hunger and satiety signals to control food-seeking behavior. We have discovered five pathways in the MB essential for hungry flies to locate and approach food. Blocking the MB-intrinsic Kenyon cells (KCs) and the MB output neurons (MBONs) in these pathways impairs food-seeking behavior. Starvation bi-directionally modulates MBON responses to a food odor, suggesting that hunger and satiety controls occur at the KC-to-MBON synapses. These controls are mediated by six types of dopaminergic neurons (DANs). By manipulating these DANs, we could inhibit food-seeking behavior in hungry flies or promote food seeking in fed flies. Finally, we show that the DANs potentially receive multiple inputs of hunger and satiety signals. This work demonstrates an information-rich central circuit in the fly brain that controls hunger-driven food-seeking behavior.
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Affiliation(s)
- Chang-Hui Tsao
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Chien-Chun Chen
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Chen-Han Lin
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan.,Department of Life Sciences and the Institute of Genome Sciences, National Yang-Ming University, Taipei, Taiwan
| | - Hao-Yu Yang
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Suewei Lin
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan.,Department of Life Sciences and the Institute of Genome Sciences, National Yang-Ming University, Taipei, Taiwan
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45
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Signaling Mode of the Broad-Spectrum Conserved CO 2 Receptor Is One of the Important Determinants of Odor Valence in Drosophila. Neuron 2018; 97:1153-1167.e4. [PMID: 29429938 DOI: 10.1016/j.neuron.2018.01.028] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2015] [Revised: 11/17/2017] [Accepted: 01/11/2018] [Indexed: 12/24/2022]
Abstract
Odor detection involves hundreds of olfactory receptors from diverse families, making modeling of hedonic valence of an odorant difficult, even in Drosophila melanogaster where most receptors have been deorphanised. We demonstrate that a broadly tuned heteromeric receptor that detects CO2 (Gr21a, Gr63a) and other odorants is a key determinant of valence along with a few members of the Odorant receptor family in a T-maze, but not in a trap assay. Gr21a and Gr63a have atypically high amino acid conservation in Dipteran insects, and they use both inhibition and activation to convey positive or negative valence for numerous odorants. Inhibitors elicit a robust Gr63a-dependent attraction, while activators, strong aversion. The attractiveness of inhibitory odorants increases with increasing background CO2 levels, providing a mechanism for behavior modulation in odor blends. In mosquitoes, valence is switched and activation of the orthologous receptor conveys attraction. Reverse chemical ecology enables the identification of inhibitory odorants to reduce attraction of mosquitoes to skin.
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46
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Sayin S, Boehm AC, Kobler JM, De Backer JF, Grunwald Kadow IC. Internal State Dependent Odor Processing and Perception-The Role of Neuromodulation in the Fly Olfactory System. Front Cell Neurosci 2018; 12:11. [PMID: 29440990 PMCID: PMC5797598 DOI: 10.3389/fncel.2018.00011] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Accepted: 01/08/2018] [Indexed: 12/21/2022] Open
Abstract
Animals rely heavily on their sense of olfaction to perform various vital interactions with an ever-in-flux environment. The turbulent and combinatorial nature of air-borne odorant cues demands the employment of various coding strategies, which allow the animal to attune to its internal needs and past or present experiences. Furthermore, these internal needs can be dependent on internal states such as hunger, reproductive state and sickness. Neuromodulation is a key component providing flexibility under such conditions. Understanding the contributions of neuromodulation, such as sensory neuron sensitization and choice bias requires manipulation of neuronal activity on a local and global scale. With Drosophila's genetic toolset, these manipulations are feasible and even allow a detailed look on the functional role of classical neuromodulators such as dopamine, octopamine and neuropeptides. The past years unraveled various mechanisms adapting chemosensory processing and perception to internal states such as hunger and reproductive state. However, future research should also investigate the mechanisms underlying other internal states including the modulatory influence of endogenous microbiota on Drosophila behavior. Furthermore, sickness induced by pathogenic infection could lead to novel insights as to the neuromodulators of circuits that integrate such a negative postingestive signal within the circuits governing olfactory behavior and learning. The enriched emporium of tools Drosophila provides will help to build a concrete picture of the influence of neuromodulation on olfaction and metabolism, adaptive behavior and our overall understanding of how a brain works.
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Affiliation(s)
- Sercan Sayin
- Neural Circuits and Metabolism, School of Life Sciences, Technische Universität München, Munich, Germany
| | - Ariane C Boehm
- Neural Circuits and Metabolism, School of Life Sciences, Technische Universität München, Munich, Germany.,Chemosensory Coding, Max Planck Institute of Neurobiology, Martinsried, Germany
| | - Johanna M Kobler
- Neural Circuits and Metabolism, School of Life Sciences, Technische Universität München, Munich, Germany.,Chemosensory Coding, Max Planck Institute of Neurobiology, Martinsried, Germany
| | - Jean-François De Backer
- Neural Circuits and Metabolism, School of Life Sciences, Technische Universität München, Munich, Germany
| | - Ilona C Grunwald Kadow
- Neural Circuits and Metabolism, School of Life Sciences, Technische Universität München, Munich, Germany.,Chemosensory Coding, Max Planck Institute of Neurobiology, Martinsried, Germany
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47
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Skora S, Mende F, Zimmer M. Energy Scarcity Promotes a Brain-wide Sleep State Modulated by Insulin Signaling in C. elegans. Cell Rep 2018; 22:953-966. [PMID: 29386137 PMCID: PMC5846868 DOI: 10.1016/j.celrep.2017.12.091] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Revised: 11/16/2017] [Accepted: 12/23/2017] [Indexed: 12/17/2022] Open
Abstract
Neural information processing entails a high energetic cost, but its maintenance is crucial for animal survival. However, the brain’s energy conservation strategies are incompletely understood. Employing functional brain-wide imaging and quantitative behavioral assays, we describe a neuronal strategy in Caenorhabditis elegans that balances energy availability and expenditure. Upon acute food deprivation, animals exhibit a transiently elevated state of arousal, indicated by foraging behaviors and increased responsiveness to food-related cues. In contrast, long-term starvation suppresses these behaviors and biases animals to intermittent sleep episodes. Brain-wide neuronal population dynamics, which are likely energetically costly but important for behavior, are robust to starvation while animals are awake. However, during starvation-induced sleep, brain dynamics are systemically downregulated. Neuromodulation via insulin-like signaling is required to transiently maintain the animals’ arousal state upon acute food deprivation. Our data suggest that the regulation of sleep and wakefulness supports optimal energy allocation. Starvation shifts the behavioral strategy from exploration to intermittent sleep Brain-wide neuronal population dynamics are robust to starvation Neuromodulation via insulin signaling maintains wakefulness during short fasting The insulin receptor DAF-2 acts in a network of sensory neurons and interneurons
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Affiliation(s)
- Susanne Skora
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Campus-Vienna-Biocenter 1, 1030 Vienna, Austria
| | - Fanny Mende
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Campus-Vienna-Biocenter 1, 1030 Vienna, Austria
| | - Manuel Zimmer
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Campus-Vienna-Biocenter 1, 1030 Vienna, Austria.
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48
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Cyclic AMP-dependent plasticity underlies rapid changes in odor coding associated with reward learning. Proc Natl Acad Sci U S A 2017; 115:E448-E457. [PMID: 29284750 DOI: 10.1073/pnas.1709037115] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Learning and memory rely on dopamine and downstream cAMP-dependent plasticity across diverse organisms. Despite the central role of cAMP signaling, it is not known how cAMP-dependent plasticity drives coherent changes in neuronal physiology that encode the memory trace, or engram. In Drosophila, the mushroom body (MB) is critically involved in olfactory classical conditioning, and cAMP signaling molecules are necessary and sufficient for normal memory in intrinsic MB neurons. To evaluate the role of cAMP-dependent plasticity in learning, we examined how cAMP manipulations and olfactory classical conditioning modulate olfactory responses in the MB with in vivo imaging. Elevating cAMP pharmacologically or optogenetically produced plasticity in MB neurons, altering their responses to odorants. Odor-evoked Ca2+ responses showed net facilitation across anatomical regions. At the single-cell level, neurons exhibited heterogeneous responses to cAMP elevation, suggesting that cAMP drives plasticity to discrete subsets of MB neurons. Olfactory appetitive conditioning enhanced MB odor responses, mimicking the cAMP-dependent plasticity in directionality and magnitude. Elevating cAMP to equivalent levels as appetitive conditioning also produced plasticity, suggesting that the cAMP generated during conditioning affects odor-evoked responses in the MB. Finally, we found that this plasticity was dependent on the Rutabaga type I adenylyl cyclase, linking cAMP-dependent plasticity to behavioral modification. Overall, these data demonstrate that learning produces robust cAMP-dependent plasticity in intrinsic MB neurons, which is biased toward naturalistic reward learning. This suggests that cAMP signaling may serve to modulate intrinsic MB responses toward salient stimuli.
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49
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Guillermin ML, Carrillo MA, Hallem EA. A Single Set of Interneurons Drives Opposite Behaviors in C. elegans. Curr Biol 2017; 27:2630-2639.e6. [PMID: 28823678 PMCID: PMC6193758 DOI: 10.1016/j.cub.2017.07.023] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Revised: 06/06/2017] [Accepted: 07/10/2017] [Indexed: 12/21/2022]
Abstract
Many chemosensory stimuli evoke innate behavioral responses that can be either appetitive or aversive, depending on an animal's age, prior experience, nutritional status, and environment [1-9]. However, the circuit mechanisms that enable these valence changes are poorly understood. Here, we show that Caenorhabditis elegans can alternate between attractive or aversive responses to carbon dioxide (CO2), depending on its recently experienced CO2 environment. Both responses are mediated by a single pathway of interneurons. The CO2-evoked activity of these interneurons is subject to extreme experience-dependent modulation, enabling them to drive opposite behavioral responses to CO2. Other interneurons in the circuit regulate behavioral sensitivity to CO2 independent of valence. A combinatorial code of neuropeptides acts on the circuit to regulate both valence and sensitivity. Chemosensory valence-encoding interneurons exist across phyla, and valence is typically determined by whether appetitive or aversive interneuron populations are activated. Our results reveal an alternative mechanism of valence determination in which the same interneurons contribute to both attractive and aversive responses through modulation of sensory neuron to interneuron synapses. This circuit design represents a previously unrecognized mechanism for generating rapid changes in innate chemosensory valence.
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Affiliation(s)
- Manon L Guillermin
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Mayra A Carrillo
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Elissa A Hallem
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA.
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50
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Lebreton S, Carlsson MA, Witzgall P. Insulin Signaling in the Peripheral and Central Nervous System Regulates Female Sexual Receptivity during Starvation in Drosophila. Front Physiol 2017; 8:685. [PMID: 28943854 PMCID: PMC5596093 DOI: 10.3389/fphys.2017.00685] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Accepted: 08/25/2017] [Indexed: 11/13/2022] Open
Abstract
Many animals adjust their reproductive behavior according to nutritional state and food availability. Drosophila females for instance decrease their sexual receptivity following starvation. Insulin signaling, which regulates many aspects of insect physiology and behavior, also affects reproduction in females. We show that insulin signaling is involved in the starvation-induced reduction in female receptivity. More specifically, females mutant for the insulin-like peptide 5 (dilp5) were less affected by starvation compared to the other dilp mutants and wild-type flies. Knocking-down the insulin receptor, either in all fruitless-positive neurons or a subset of these neurons dedicated to the perception of a male aphrodisiac pheromone, decreased the effect of starvation on female receptivity. Disrupting insulin signaling in some parts of the brain, including the mushroom bodies even abolished the effect of starvation. In addition, we identified fruitless-positive neurons in the dorso-lateral protocerebrum and in the mushroom bodies co-expressing the insulin receptor. Together, our results suggest that the interaction of insulin peptides determines the tuning of female sexual behavior, either by acting on pheromone perception or directly in the central nervous system.
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Affiliation(s)
- Sébastien Lebreton
- Division of Chemical Ecology, Department of Plant Protection Biology, Swedish University of Agricultural SciencesAlnarp, Sweden
| | | | - Peter Witzgall
- Division of Chemical Ecology, Department of Plant Protection Biology, Swedish University of Agricultural SciencesAlnarp, Sweden
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