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Fowler EK, Friend LA, Churchill ER, Yu DW, Archetti M, Bourke AFG, Bretman A, Chapman T. Female oviposition decisions are influenced by the microbial environment. J Evol Biol 2025; 38:379-390. [PMID: 39820424 DOI: 10.1093/jeb/voaf004] [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: 07/30/2024] [Revised: 11/28/2024] [Accepted: 01/14/2025] [Indexed: 01/19/2025]
Abstract
In ovipositing animals, egg placement decisions can be key determinants of offspring survival. One oviposition strategy reported across taxa is laying eggs in clusters. In some species, mothers provision eggs with diffusible defence compounds, such as antimicrobials, raising the possibility of public good benefits arising from egg clustering. Here we report that Drosophila melanogaster females frequently lay eggs in mixed-maternity clusters. We tested two hypotheses for potential drivers of this oviposition behaviour: (i) the microbial environment affects fecundity and egg placement in groups of females; (ii) eggs exhibit antimicrobial activity. The results partially supported the first hypothesis. Females reduced egg laying but did not alter egg clustering, on non-sterile substrates that had been naturally colonized with microbes from the environment. However, oviposition remained unaffected when the substrate community consisted of commensal (fly-associated) microbes. The second hypothesis was not supported. There was no evidence of antimicrobial activity, either in whole eggs or in soluble egg-surface material. In conclusion, while we found no behavioural or physiological evidence that egg clustering decisions are shaped by the opportunity to share antimicrobials, females are sensitive to their microbial environment and can adjust egg-laying rates accordingly.
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Affiliation(s)
- Emily K Fowler
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, United Kingdom
| | - Lucy A Friend
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, United Kingdom
| | - Emily R Churchill
- Faculty of Biological Sciences, School of Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Douglas W Yu
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, United Kingdom
| | - Marco Archetti
- Department of Biology, Pennsylvania State University, University Park, PA 16802, United States
| | - Andrew F G Bourke
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, United Kingdom
| | - Amanda Bretman
- Faculty of Biological Sciences, School of Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Tracey Chapman
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, United Kingdom
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2
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Moreira-Soto RD, Hansson BS, Knaden M. Oviposition Dynamics and Niche Utilization in Two Sympatric Drosophila Species. J Chem Ecol 2025; 51:21. [PMID: 39904815 PMCID: PMC11794365 DOI: 10.1007/s10886-025-01576-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2024] [Revised: 01/22/2025] [Accepted: 01/23/2025] [Indexed: 02/06/2025]
Abstract
Many Drosophila species coexist by sharing their feeding and breeding sites, which may influence their oviposition choices in an interspecies social context. Whether and where to lay eggs is a crucial decision for female flies as it influences the success of their offspring, by minimizing the risk of predation, competition, or cannibalism. Significant gaps exist in our understanding of Drosophila oviposition dynamics in co-occurring species. Here we tested oviposition strategies of Drosophila melanogaster and its close relative Drosophila simulans under different conditions, to assess whether a single female would prefer to oviposit separately or together with another female, be it a conspecific or not. We find that ovipositing females, regardless whether they are conspecifics or not, prefer to oviposit at the same site. This might suggest that the flies regard the benefits of sharing oviposition sites as higher than the potential risks of competition or cannibalism. The willingness to share oviposition sites was lower when the nutritional value of the medium was increased by adding yeast, and was lost when flies were allowed to lay the eggs consecutively, instead of being tested together. The latter might be explained by our additional finding that females become attracted by the presence of other females on oviposition substrates and that this attraction is partly driven by visual cues. Ovipositing in groups might facilitate intra- and interspecific social feeding of same age offspring, as well as enrichment of microbes. However, this cooperation dynamic might change if another female's offspring is already present, as it might be perceived as danger of competition or cannibalism.
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Affiliation(s)
- Rolando D Moreira-Soto
- Department of Evolutionary Neuroethology, Max-Planck Institute for Chemical Ecology, Jena, Germany
- Universidad de Costa Rica, Centro de Investigación en Enfermedades Tropicales, Facultad de Microbiología, San José, Costa Rica
| | - Bill S Hansson
- Department of Evolutionary Neuroethology, Max-Planck Institute for Chemical Ecology, Jena, Germany
| | - Markus Knaden
- Department of Evolutionary Neuroethology, Max-Planck Institute for Chemical Ecology, Jena, Germany.
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3
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Bowland AC, Melin AD, Hosken DJ, Hockings KJ, Carrigan MA. The evolutionary ecology of ethanol. Trends Ecol Evol 2025; 40:67-79. [PMID: 39482197 DOI: 10.1016/j.tree.2024.09.005] [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: 07/05/2024] [Revised: 09/16/2024] [Accepted: 09/18/2024] [Indexed: 11/03/2024]
Abstract
The consumption of ethanol has frequently been seen as largely restricted to humans. Here, we take a broad eco-evolutionary approach to understanding ethanol's potential impact on the natural world. There is growing evidence that ethanol is present in many wild fruits, saps, and nectars and that ethanol ingestion offers benefits that favour adaptations for its use in multiple taxa. Explanations for ethanol consumption span both the nutritional and non-nutritional, with potential medicinal value or cognitive effects (with social-behavioural benefits) explored. We conclude that ethanol is ecologically relevant and that it has shaped the evolution of many species and structured symbiotic relationships among organisms, including plants, yeast, bacteria, insects, and mammals.
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Affiliation(s)
- Anna C Bowland
- Centre for Ecology and Conservation, Faculty of Environment, Science and Economy, University of Exeter, Penryn Campus, Cornwall, UK
| | - Amanda D Melin
- Department of Anthropology and Archaeology, University of Calgary, Calgary, Alberta, Canada
| | - David J Hosken
- Centre for Ecology and Conservation, Faculty of Environment, Science and Economy, University of Exeter, Penryn Campus, Cornwall, UK
| | - Kimberley J Hockings
- Centre for Ecology and Conservation, Faculty of Environment, Science and Economy, University of Exeter, Penryn Campus, Cornwall, UK.
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4
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Peterson SK, Ahmad ST. A Brief Overview of Ethanol Tolerance and Its Potential Association with Circadian Rhythm in Drosophila. Int J Mol Sci 2024; 25:12605. [PMID: 39684317 PMCID: PMC11641815 DOI: 10.3390/ijms252312605] [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: 10/16/2024] [Revised: 11/21/2024] [Accepted: 11/22/2024] [Indexed: 12/18/2024] Open
Abstract
Alcohol consumption and addiction remain global health concerns, with significant loss of productivity, morbidity, and mortality. Drosophila melanogaster, a widely used model organism, offers valuable insights into the genetic and neuronal mechanisms underlying ethanol-induced behaviors (EIBs) such as sedation, recovery, and tolerance. This narrative review focuses on studies in the Drosophila model system suggesting an association between circadian rhythm genes as modulators of ethanol tolerance. Mutations in these genes disrupt both the circadian cycle and tolerance, underscoring the interplay between circadian rhythm and ethanol processing although the exact mechanisms remain largely unknown. Additionally, genes involved in stress response, gene expression regulation, neurotransmission, and synaptic activity were implicated in ethanol tolerance modulation. At the neuronal level, recent studies have highlighted the involvement of corazonin (CRZ) and neuropeptide F (NPF) neurons in modulating EIBs. Understanding the temporal dynamics of tolerance development is crucial for describing the molecular basis of ethanol tolerance. Ultimately, insights gained from Drosophila studies hold promise for elucidating the neurobiological underpinnings of alcohol use disorders and addiction, contributing to more effective interventions and treatments.
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Affiliation(s)
| | - S. Tariq Ahmad
- Department of Biology, Colby College, Waterville, ME 04901, USA;
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5
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Mohammad F, Mai Y, Ho J, Zhang X, Ott S, Stewart JC, Claridge-Chang A. Dopamine neurons that inform Drosophila olfactory memory have distinct, acute functions driving attraction and aversion. PLoS Biol 2024; 22:e3002843. [PMID: 39556592 DOI: 10.1371/journal.pbio.3002843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Accepted: 09/16/2024] [Indexed: 11/20/2024] Open
Abstract
The brain must guide immediate responses to beneficial and harmful stimuli while simultaneously writing memories for future reference. While both immediate actions and reinforcement learning are instructed by dopamine, how dopaminergic systems maintain coherence between these 2 reward functions is unknown. Through optogenetic activation experiments, we showed that the dopamine neurons that inform olfactory memory in Drosophila have a distinct, parallel function driving attraction and aversion (valence). Sensory neurons required for olfactory memory were dispensable to dopaminergic valence. A broadly projecting set of dopaminergic cells had valence that was dependent on dopamine, glutamate, and octopamine. Similarly, a more restricted dopaminergic cluster with attractive valence was reliant on dopamine and glutamate; flies avoided opto-inhibition of this narrow subset, indicating the role of this cluster in controlling ongoing behavior. Dopamine valence was distinct from output-neuron opto-valence in locomotor pattern, strength, and polarity. Overall, our data suggest that dopamine's acute effect on valence provides a mechanism by which a dopaminergic system can coherently write memories to influence future responses while guiding immediate attraction and aversion.
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Affiliation(s)
- Farhan Mohammad
- Program in Neuroscience and Behavioural Disorders, Duke-NUS Medical School, Singapore
- Institute for Molecular and Cell Biology, A*STAR, Singapore
- Division of Biological and Biomedical Sciences, College of Health & Life Sciences, Hamad Bin Khalifa University, Qatar
| | - Yishan Mai
- Program in Neuroscience and Behavioural Disorders, Duke-NUS Medical School, Singapore
| | - Joses Ho
- Institute for Molecular and Cell Biology, A*STAR, Singapore
| | - Xianyuan Zhang
- Program in Neuroscience and Behavioural Disorders, Duke-NUS Medical School, Singapore
- Department of Pharmacology, National University of Singapore, Singapore
| | - Stanislav Ott
- Program in Neuroscience and Behavioural Disorders, Duke-NUS Medical School, Singapore
| | | | - Adam Claridge-Chang
- Program in Neuroscience and Behavioural Disorders, Duke-NUS Medical School, Singapore
- Institute for Molecular and Cell Biology, A*STAR, Singapore
- Department of Physiology, National University of Singapore, Singapore
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6
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Zak H, Rozenfeld E, Levi M, Deng P, Gorelick D, Pozeilov H, Israel S, Paas Y, Paas Y, Li JB, Parnas M, Shohat-Ophir G. A highly conserved A-to-I RNA editing event within the glutamate-gated chloride channel GluClα is necessary for olfactory-based behaviors in Drosophila. SCIENCE ADVANCES 2024; 10:eadi9101. [PMID: 39231215 PMCID: PMC11373593 DOI: 10.1126/sciadv.adi9101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Accepted: 07/29/2024] [Indexed: 09/06/2024]
Abstract
A-to-I RNA editing is a cellular mechanism that generates transcriptomic and proteomic diversity, which is essential for neuronal and immune functions. It involves the conversion of specific adenosines in RNA molecules to inosines, which are recognized as guanosines by cellular machinery. Despite the vast number of editing sites observed across the animal kingdom, pinpointing critical sites and understanding their in vivo functions remains challenging. Here, we study the function of an evolutionary conserved editing site in Drosophila, located in glutamate-gated chloride channel (GluClα). Our findings reveal that flies lacking editing at this site exhibit reduced olfactory responses to odors and impaired pheromone-dependent social interactions. Moreover, we demonstrate that editing of this site is crucial for the proper processing of olfactory information in projection neurons. Our results highlight the value of using evolutionary conservation as a criterion for identifying editing events with potential functional significance and paves the way for elucidating the intricate link between RNA modification, neuronal physiology, and behavior.
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Affiliation(s)
- Hila Zak
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 5290002, Israel
- Bar-Ilan University, Ramat Gan 5290002, Israel
- The Nanotechnology Institute, Bar-Ilan University, Ramat Gan 5290002, 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
| | - Mali Levi
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 5290002, Israel
- Bar-Ilan University, Ramat Gan 5290002, Israel
- The Nanotechnology Institute, Bar-Ilan University, Ramat Gan 5290002, Israel
| | - Patricia Deng
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - David Gorelick
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 5290002, Israel
- Bar-Ilan University, Ramat Gan 5290002, Israel
- The Nanotechnology Institute, Bar-Ilan University, Ramat Gan 5290002, Israel
| | - Hadar Pozeilov
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 5290002, Israel
- Bar-Ilan University, Ramat Gan 5290002, Israel
- The Nanotechnology Institute, Bar-Ilan University, Ramat Gan 5290002, Israel
| | - Shai Israel
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 5290002, Israel
- Bar-Ilan University, Ramat Gan 5290002, Israel
- The Nanotechnology Institute, Bar-Ilan University, Ramat Gan 5290002, Israel
- 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
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Yoav Paas
- 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
| | - Yoav Paas
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 5290002, Israel
| | - Jin Billy Li
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - 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
| | - Galit Shohat-Ophir
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 5290002, Israel
- Bar-Ilan University, Ramat Gan 5290002, Israel
- The Nanotechnology Institute, Bar-Ilan University, Ramat Gan 5290002, Israel
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7
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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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8
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Larnerd C, Kachewar N, Wolf FW. Drosophila learning and memory centers and the actions of drugs of abuse. Learn Mem 2024; 31:a053815. [PMID: 38862166 PMCID: PMC11199947 DOI: 10.1101/lm.053815.123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2024] [Accepted: 03/27/2024] [Indexed: 06/13/2024]
Abstract
Drug addiction and the circuitry for learning and memory are intimately intertwined. Drugs of abuse create strong, inappropriate, and lasting memories that contribute to many of their destructive properties, such as continued use despite negative consequences and exceptionally high rates of relapse. Studies in Drosophila melanogaster are helping us understand how drugs of abuse, especially alcohol, create memories at the level of individual neurons and in the circuits where they function. Drosophila is a premier organism for identifying the mechanisms of learning and memory. Drosophila also respond to drugs of abuse in ways that remarkably parallel humans and rodent models. An emerging consensus is that, for alcohol, the mushroom bodies participate in the circuits that control acute drug sensitivity, not explicitly associative forms of plasticity such as tolerance, and classical associative memories of their rewarding and aversive properties. Moreover, it is becoming clear that drugs of abuse use the mushroom body circuitry differently from other behaviors, potentially providing a basis for their addictive properties.
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Affiliation(s)
- Caleb Larnerd
- Quantitative and Systems Biology Graduate Group, University of California, Merced, California 95343, USA
| | - Neha Kachewar
- Department of Molecular and Cell Biology, University of California, Merced, California 95343, USA
- Health Sciences Research Institute, University of California, Merced, California 95343, USA
| | - Fred W Wolf
- Quantitative and Systems Biology Graduate Group, University of California, Merced, California 95343, USA
- Department of Molecular and Cell Biology, University of California, Merced, California 95343, USA
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9
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Wang C, Hu Z, Guo Y, Xiao W, Zhang Y, Zhou A, Chen P. The Role of BmTMED6 in Female Reproduction in Silkworm, Bombyx mori. INSECTS 2024; 15:103. [PMID: 38392522 PMCID: PMC10889480 DOI: 10.3390/insects15020103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Revised: 01/09/2024] [Accepted: 01/13/2024] [Indexed: 02/24/2024]
Abstract
Transmembrane emp24 domain (TMED) proteins have been extensively studied in mammalian embryonic development, immune regulation, and signal transduction. However, their role in insects, apart from Drosophila melanogaster, remains largely unexplored. Our previous study demonstrated the abundant expression of BmTMED6 across all stages and tissues of the silkworm. In this study, we investigate the function of BmTMED6 in reproduction. We observe significant differences in the expression of BmTMED6 between male and female silkworms, particularly in the head and fatboby, during the larval stage. Furthermore, qRT-PCR and WB analysis reveal substantial variation in BmTMED6 levels in the ovaries during pupal development, suggesting a potential association with silkworm female reproduction. We find that reducing TMED6 expression significantly decreases the number of eggs laid by female moths, leading to an accumulation of unlaid eggs in the abdomen. Moreover, downregulation of BmTMED6 leads to a decrease in the expression of BmDop2R1 and BmDop2R2, while overexpression of BmTMED6 in vitro has the opposite effect. These indicate that BmTMED6 plays a role in oviposition in female moths, potentially through the dopamine signaling pathway. This study provides a new regulatory mechanism for female reproduction in insects.
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Affiliation(s)
- Chunyang Wang
- College of Sericulture, Textile and Biomass Sciences, Southwest University, Chongqing 400715, China
| | - Zunmei Hu
- College of Sericulture, Textile and Biomass Sciences, Southwest University, Chongqing 400715, China
| | - Yu Guo
- College of Sericulture, Textile and Biomass Sciences, Southwest University, Chongqing 400715, China
| | - Wenfu Xiao
- Sericultural Research Institute, Sichuan Academy of Agricultural Sciences, Nanchong 637000, China
| | - Youhong Zhang
- Sericultural Research Institute, Sichuan Academy of Agricultural Sciences, Nanchong 637000, China
| | - Anlian Zhou
- Sericultural Research Institute, Sichuan Academy of Agricultural Sciences, Nanchong 637000, China
| | - Ping Chen
- College of Sericulture, Textile and Biomass Sciences, Southwest University, Chongqing 400715, China
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400715, China
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10
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Oliveira-Ferreira C, Gaspar M, Vasconcelos ML. Neuronal substrates of egg-laying behaviour at the abdominal ganglion of Drosophila melanogaster. Sci Rep 2023; 13:21941. [PMID: 38081887 PMCID: PMC10713638 DOI: 10.1038/s41598-023-48109-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Accepted: 11/22/2023] [Indexed: 12/18/2023] Open
Abstract
Egg-laying in Drosophila is the product of post-mating physiological and behavioural changes that culminate in a stereotyped sequence of actions. Egg-laying harbours a great potential as a paradigm to uncover how the appropriate motor circuits are organized and activated to generate behaviour. To study this programme, we first describe the different phases of the egg-laying programme and the specific actions associated with each phase. Using a combination of neuronal activation and silencing experiments, we identify neurons (OvAbg) in the abdominal ganglion as key players in egg-laying. To generate and functionally characterise subsets of OvAbg, we used an intersectional approach with neurotransmitter specific lines-VGlut, Cha and Gad1. We show that OvAbg/VGlut neurons promote initiation of egg deposition in a mating status dependent way. OvAbg/Cha neurons are required in exploration and egg deposition phases, though activation leads specifically to egg expulsion. Experiments with the OvAbg/Gad1 neurons show they participate in egg deposition. We further show a functional connection of OvAbg neurons with brain neurons. This study provides insight into the organization of neuronal circuits underlying complex motor behaviour.
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Affiliation(s)
| | - Miguel Gaspar
- Neuroscience Programme, Champalimaud Foundation, Lisbon, Portugal
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11
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Nuñez KM, Catalano JL, Scaplen KM, Kaun KR. Ethanol Behavioral Responses in Drosophila. Cold Spring Harb Protoc 2023; 2023:719-24. [PMID: 37019606 PMCID: PMC10551053 DOI: 10.1101/pdb.top107887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2023]
Abstract
Drosophila melanogaster is a powerful genetic model for investigating the mechanisms underlying ethanol-induced behaviors, metabolism, and preference. Ethanol-induced locomotor activity is especially useful for understanding the mechanisms by which ethanol acutely affects the brain and behavior. Ethanol-induced locomotor activity is characterized by hyperlocomotion and subsequent sedation with increased exposure duration or concentration. Locomotor activity is an efficient, easy, robust, and reproducible behavioral screening tool for identifying underlying genes and neuronal circuits as well as investigating genetic and molecular pathways. We introduce a detailed protocol for performing experiments investigating how volatilized ethanol affects locomotor activity using the fly Group Activity Monitor (flyGrAM). We introduce installation, implementation, data collection, and subsequent data-analysis methods for investigating how volatilized stimuli affect activity. We also introduce a procedure for how to optogenetically probe neuronal activity to identify the neural mechanisms underlying locomotor activity.
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Affiliation(s)
- Kavin M Nuñez
- Molecular Pharmacology and Physiology Graduate Program, Brown University, Providence, Rhode Island 02912, USA
| | - Jamie L Catalano
- Molecular Pharmacology and Physiology Graduate Program, Brown University, Providence, Rhode Island 02912, USA
| | - Kristin M Scaplen
- Department of Psychology, Bryant University, Smithfield, Rhode Island 02917, USA
- Center for Health and Behavioral Sciences, Bryant University, Smithfield, Rhode Island 02917, USA
- Department of Neuroscience, Brown University, Providence, Rhode Island 02912, USA
| | - Karla R Kaun
- Department of Neuroscience, Brown University, Providence, Rhode Island 02912, USA
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12
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Metaxakis A, Pavlidis M, Tavernarakis N. Neuronal atg1 Coordinates Autophagy Induction and Physiological Adaptations to Balance mTORC1 Signalling. Cells 2023; 12:2024. [PMID: 37626835 PMCID: PMC10453232 DOI: 10.3390/cells12162024] [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: 07/11/2023] [Revised: 08/04/2023] [Accepted: 08/05/2023] [Indexed: 08/27/2023] Open
Abstract
The mTORC1 nutrient-sensing pathway integrates metabolic and endocrine signals into the brain to evoke physiological responses to food deprivation, such as autophagy. Nevertheless, the impact of neuronal mTORC1 activity on neuronal circuits and organismal metabolism remains obscure. Here, we show that mTORC1 inhibition acutely perturbs serotonergic neurotransmission via proteostatic alterations evoked by the autophagy inducer atg1. Neuronal ATG1 alters the intracellular localization of the serotonin transporter, which increases the extracellular serotonin and stimulates the 5HTR7 postsynaptic receptor. 5HTR7 enhances food-searching behaviour and ecdysone-induced catabolism in Drosophila. Along similar lines, the pharmacological inhibition of mTORC1 in zebrafish also stimulates food-searching behaviour via serotonergic activity. These effects occur in parallel with neuronal autophagy induction, irrespective of the autophagic activity and the protein synthesis reduction. In addition, ectopic neuronal atg1 expression enhances catabolism via insulin pathway downregulation, impedes peptidergic secretion, and activates non-cell autonomous cAMP/PKA. The above exert diverse systemic effects on organismal metabolism, development, melanisation, and longevity. We conclude that neuronal atg1 aligns neuronal autophagy induction with distinct physiological modulations, to orchestrate a coordinated physiological response against reduced mTORC1 activity.
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Affiliation(s)
- Athanasios Metaxakis
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology Hellas, Nikolaou Plastira 100, 70013 Heraklion, Crete, Greece
| | - Michail Pavlidis
- Department of Biology, University of Crete, 71409 Heraklion, Crete, Greece;
| | - Nektarios Tavernarakis
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology Hellas, Nikolaou Plastira 100, 70013 Heraklion, Crete, Greece
- Department of Basic Sciences, Faculty of Medicine, University of Crete, 71110 Heraklion, Crete, Greece
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13
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Gendron CM, Chakraborty TS, Duran C, Dono T, Pletcher SD. Ring neurons in the Drosophila central complex act as a rheostat for sensory modulation of aging. PLoS Biol 2023; 21:e3002149. [PMID: 37310911 PMCID: PMC10263353 DOI: 10.1371/journal.pbio.3002149] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Accepted: 05/03/2023] [Indexed: 06/15/2023] Open
Abstract
Sensory perception modulates aging, yet we know little about how. An understanding of the neuronal mechanisms through which animals orchestrate biological responses to relevant sensory inputs would provide insight into the control systems that may be important for modulating lifespan. Here, we provide new awareness into how the perception of dead conspecifics, or death perception, which elicits behavioral and physiological effects in many different species, affects lifespan in the fruit fly, Drosophila melanogaster. Previous work demonstrated that cohousing Drosophila with dead conspecifics decreases fat stores, reduces starvation resistance, and accelerates aging in a manner that requires both sight and the serotonin receptor 5-HT2A. In this manuscript, we demonstrate that a discrete, 5-HT2A-expressing neural population in the ellipsoid body (EB) of the Drosophila central complex, identified as R2/R4 neurons, acts as a rheostat and plays an important role in transducing sensory information about the presence of dead individuals to modulate lifespan. Expression of the insulin-responsive transcription factor foxo in R2/R4 neurons and insulin-like peptides dilp3 and dilp5, but not dilp2, are required, with the latter likely altered in median neurosecretory cells (MNCs) after R2/R4 neuronal activation. These data generate new insights into the neural underpinnings of how perceptive events may impact aging and physiology across taxa.
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Affiliation(s)
- Christi M. Gendron
- Department of Molecular and Integrative Physiology and Geriatrics Center, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Tuhin S. Chakraborty
- Department of Molecular and Integrative Physiology and Geriatrics Center, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Cathryn Duran
- Department of Molecular and Integrative Physiology and Geriatrics Center, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Thomas Dono
- Department of Molecular and Integrative Physiology and Geriatrics Center, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Scott D. Pletcher
- Department of Molecular and Integrative Physiology and Geriatrics Center, University of Michigan, Ann Arbor, Michigan, United States of America
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14
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Fanara JJ, Beti MIL, Gandini L, Hasson E. Oviposition behaviour in Drosophila melanogaster: Genetic and behavioural decoupling between oviposition acceptance and preference for natural fruits. J Evol Biol 2023; 36:251-263. [PMID: 36357966 DOI: 10.1111/jeb.14109] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 06/28/2022] [Accepted: 07/05/2022] [Indexed: 11/12/2022]
Abstract
In phytophagous insects, oviposition behaviour is an important component of habitat selection and, given the multiplicity of genetic and environmental factors affecting its expression, is defined as a complex character resulting from the sum of interdependent traits. Here, we study two components of egg-laying behaviour: oviposition acceptance (OA) and oviposition preference (OP) in Drosophila melanogaster using three natural fruits as resources (grape, tomato and orange) by means of no-choice and two-choice experiments, respectively. This experimental design allowed us to show that the results obtained in two-choice assays (OP) cannot be accounted for by those resulting from no-choice assays (OA). Since the genomes of all lines used are completely sequenced, we perform a genome-wide association study to identify and characterize the genetic underpinnings of these oviposition behaviour traits. The analyses revealed different candidate genes affecting natural genetic variation of both OA and OP traits. Moreover, our results suggest behavioural and genetic decoupling between OA and OP and that egg-laying behaviour is plastic and context-dependent. Such independence in the genetic architectures of OA and OP variation may influence different aspects of oviposition behaviour, including plasticity, canalization, host shift and maintenance of genetic variability, which contributes to the adoption of adaptive strategies during habitat selection.
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Affiliation(s)
- Juan J Fanara
- Laboratorio de Evolución, Departamento de Ecología, Genética y Evolución, FCEN, Universidad de Buenos Aires, Pabellón II, Ciudad Universitaria, Buenos Aires, Argentina.,Laboratorio de Evolución, Instituto de Ecología, Genética y Evolución de Buenos Aires (IEGEBA), CONICET-UBA, FCEN, Universidad de Buenos Aires, Pabellón II, Ciudad Universitaria, Buenos Aires, Argentina
| | - Maria I L Beti
- Laboratorio de Evolución, Instituto de Ecología, Genética y Evolución de Buenos Aires (IEGEBA), CONICET-UBA, FCEN, Universidad de Buenos Aires, Pabellón II, Ciudad Universitaria, Buenos Aires, Argentina
| | - Luciano Gandini
- Laboratorio de Evolución, Departamento de Ecología, Genética y Evolución, FCEN, Universidad de Buenos Aires, Pabellón II, Ciudad Universitaria, Buenos Aires, Argentina
| | - Esteban Hasson
- Laboratorio de Evolución, Departamento de Ecología, Genética y Evolución, FCEN, Universidad de Buenos Aires, Pabellón II, Ciudad Universitaria, Buenos Aires, Argentina.,Laboratorio de Evolución, Instituto de Ecología, Genética y Evolución de Buenos Aires (IEGEBA), CONICET-UBA, FCEN, Universidad de Buenos Aires, Pabellón II, Ciudad Universitaria, Buenos Aires, Argentina
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15
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Rosikon KD, Bone MC, Lawal HO. Regulation and modulation of biogenic amine neurotransmission in Drosophila and Caenorhabditis elegans. Front Physiol 2023; 14:970405. [PMID: 36875033 PMCID: PMC9978017 DOI: 10.3389/fphys.2023.970405] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Accepted: 01/23/2023] [Indexed: 02/18/2023] Open
Abstract
Neurotransmitters are crucial for the relay of signals between neurons and their target. Monoamine neurotransmitters dopamine (DA), serotonin (5-HT), and histamine are found in both invertebrates and mammals and are known to control key physiological aspects in health and disease. Others, such as octopamine (OA) and tyramine (TA), are abundant in invertebrates. TA is expressed in both Caenorhabditis elegans and Drosophila melanogaster and plays important roles in the regulation of essential life functions in each organism. OA and TA are thought to act as the mammalian homologs of epinephrine and norepinephrine respectively, and when triggered, they act in response to the various stressors in the fight-or-flight response. 5-HT regulates a wide range of behaviors in C. elegans including egg-laying, male mating, locomotion, and pharyngeal pumping. 5-HT acts predominantly through its receptors, of which various classes have been described in both flies and worms. The adult brain of Drosophila is composed of approximately 80 serotonergic neurons, which are involved in modulation of circadian rhythm, feeding, aggression, and long-term memory formation. DA is a major monoamine neurotransmitter that mediates a variety of critical organismal functions and is essential for synaptic transmission in invertebrates as it is in mammals, in which it is also a precursor for the synthesis of adrenaline and noradrenaline. In C. elegans and Drosophila as in mammals, DA receptors play critical roles and are generally grouped into two classes, D1-like and D2-like based on their predicted coupling to downstream G proteins. Drosophila uses histamine as a neurotransmitter in photoreceptors as well as a small number of neurons in the CNS. C. elegans does not use histamine as a neurotransmitter. Here, we review the comprehensive set of known amine neurotransmitters found in invertebrates, and discuss their biological and modulatory functions using the vast literature on both Drosophila and C. elegans. We also suggest the potential interactions between aminergic neurotransmitters systems in the modulation of neurophysiological activity and behavior.
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Affiliation(s)
- Katarzyna D Rosikon
- Neuroscience Program, Department of Biological Sciences, Delaware State University, Dover, DE, United States
| | - Megan C Bone
- Neuroscience Program, Department of Biological Sciences, Delaware State University, Dover, DE, United States
| | - Hakeem O Lawal
- Neuroscience Program, Department of Biological Sciences, Delaware State University, Dover, DE, United States
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16
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Karigo T, Deutsch D. Flexibility of neural circuits regulating mating behaviors in mice and flies. Front Neural Circuits 2022; 16:949781. [PMID: 36426135 PMCID: PMC9679785 DOI: 10.3389/fncir.2022.949781] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2022] [Accepted: 07/28/2022] [Indexed: 11/11/2022] Open
Abstract
Mating is essential for the reproduction of animal species. As mating behaviors are high-risk and energy-consuming processes, it is critical for animals to make adaptive mating decisions. This includes not only finding a suitable mate, but also adapting mating behaviors to the animal's needs and environmental conditions. Internal needs include physical states (e.g., hunger) and emotional states (e.g., fear), while external conditions include both social cues (e.g., the existence of predators or rivals) and non-social factors (e.g., food availability). With recent advances in behavioral neuroscience, we are now beginning to understand the neural basis of mating behaviors, particularly in genetic model organisms such as mice and flies. However, how internal and external factors are integrated by the nervous system to enable adaptive mating-related decision-making in a state- and context-dependent manner is less well understood. In this article, we review recent knowledge regarding the neural basis of flexible mating behaviors from studies of flies and mice. By contrasting the knowledge derived from these two evolutionarily distant model organisms, we discuss potential conserved and divergent neural mechanisms involved in the control of flexible mating behaviors in invertebrate and vertebrate brains.
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Affiliation(s)
- Tomomi Karigo
- Kennedy Krieger Institute, Baltimore, MD, United States,The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, United States,*Correspondence: Tomomi Karigo,
| | - David Deutsch
- Sagol Department of Neurobiology, Faculty of Natural Sciences, University of Haifa, Haifa, Israel,David Deutsch,
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17
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Vijayan V, Wang Z, Chandra V, Chakravorty A, Li R, Sarbanes SL, Akhlaghpour H, Maimon G. An internal expectation guides Drosophila egg-laying decisions. SCIENCE ADVANCES 2022; 8:eabn3852. [PMID: 36306348 PMCID: PMC9616500 DOI: 10.1126/sciadv.abn3852] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
To better understand how animals make ethologically relevant decisions, we studied egg-laying substrate choice in Drosophila. We found that flies dynamically increase or decrease their egg-laying rates while exploring substrates so as to target eggs to the best, recently visited option. Visiting the best option typically yielded inhibition of egg laying on other substrates for many minutes. Our data support a model in which flies compare the current substrate's value with an internally constructed expectation on the value of available options to regulate the likelihood of laying an egg. We show that dopamine neuron activity is critical for learning and/or expressing this expectation, similar to its role in certain tasks in vertebrates. Integrating sensory experiences over minutes to generate an estimate of the quality of available options allows flies to use a dynamic reference point for judging the current substrate and might be a general way in which decisions are made.
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18
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Boehm AC, Friedrich AB, Hunt S, Bandow P, Siju KP, De Backer JF, Claussen J, Link MH, Hofmann TF, Dawid C, Grunwald Kadow IC. A dopamine-gated learning circuit underpins reproductive state-dependent odor preference in Drosophila females. eLife 2022; 11:e77643. [PMID: 36129174 PMCID: PMC9536836 DOI: 10.7554/elife.77643] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Accepted: 09/20/2022] [Indexed: 11/13/2022] Open
Abstract
Motherhood induces a drastic, sometimes long-lasting, change in internal state and behavior in many female animals. How a change in reproductive state or the discrete event of mating modulates specific female behaviors is still incompletely understood. Using calcium imaging of the whole brain of Drosophila females, we find that mating does not induce a global change in brain activity. Instead, mating modulates the pheromone response of dopaminergic neurons innervating the fly's learning and memory center, the mushroom body (MB). Using the mating-induced increased attraction to the odor of important nutrients, polyamines, we show that disruption of the female fly's ability to smell, for instance the pheromone cVA, during mating leads to a reduction in polyamine preference for days later indicating that the odor environment at mating lastingly influences female perception and choice behavior. Moreover, dopaminergic neurons including innervation of the β'1 compartment are sufficient to induce the lasting behavioral increase in polyamine preference. We further show that MB output neurons (MBON) of the β'1 compartment are activated by pheromone odor and their activity during mating bidirectionally modulates preference behavior in mated and virgin females. Their activity is not required, however, for the expression of polyamine attraction. Instead, inhibition of another type of MBON innervating the β'2 compartment enables expression of high odor attraction. In addition, the response of a lateral horn (LH) neuron, AD1b2, which output is required for the expression of polyamine attraction, shows a modulated polyamine response after mating. Taken together, our data in the fly suggests that mating-related sensory experience regulates female odor perception and expression of choice behavior through a dopamine-gated learning circuit.
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Affiliation(s)
- Ariane C Boehm
- Technical University Munich, School of Life Sciences, Neuronal Control of MetabolismFreisingGermany
- Graduate School of Systemic Neurosciences, Ludwig Maximilian UniversityMartinsriedGermany
| | - Anja B Friedrich
- Technical University Munich, School of Life Sciences, Neuronal Control of MetabolismFreisingGermany
| | - Sydney Hunt
- Technical University Munich, School of Life Sciences, Neuronal Control of MetabolismFreisingGermany
| | - Paul Bandow
- Technical University Munich, School of Life Sciences, Neuronal Control of MetabolismFreisingGermany
- Graduate School of Systemic Neurosciences, Ludwig Maximilian UniversityMartinsriedGermany
- ZIEL – Institute for Food and Health, Technical University Munich, School of Life SciencesFreisingGermany
| | - KP Siju
- Technical University Munich, School of Life Sciences, Neuronal Control of MetabolismFreisingGermany
| | - Jean Francois De Backer
- Technical University Munich, School of Life Sciences, Neuronal Control of MetabolismFreisingGermany
| | - Julia Claussen
- Technical University Munich, School of Life Sciences, Neuronal Control of MetabolismFreisingGermany
| | - Marie Helen Link
- Technical University Munich, School of Life Sciences, Neuronal Control of MetabolismFreisingGermany
| | - Thomas F Hofmann
- ZIEL – Institute for Food and Health, Technical University Munich, School of Life SciencesFreisingGermany
- Technical University Munich, School of Life Sciences, Chair of Food Chemistry and Molecular Sensory ScienceFreisingGermany
| | - Corinna Dawid
- ZIEL – Institute for Food and Health, Technical University Munich, School of Life SciencesFreisingGermany
- Technical University Munich, School of Life Sciences, Chair of Food Chemistry and Molecular Sensory ScienceFreisingGermany
| | - Ilona C Grunwald Kadow
- Technical University Munich, School of Life Sciences, Neuronal Control of MetabolismFreisingGermany
- Graduate School of Systemic Neurosciences, Ludwig Maximilian UniversityMartinsriedGermany
- ZIEL – Institute for Food and Health, Technical University Munich, School of Life SciencesFreisingGermany
- University of Bonn, Faculty of Medicine, Institute of Physiology IIBonnGermany
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19
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Rahul, Siddique YH. Drosophila: A Model to Study the Pathogenesis of Parkinson's Disease. CNS & NEUROLOGICAL DISORDERS DRUG TARGETS 2022; 21:259-277. [PMID: 35040399 DOI: 10.2174/1871527320666210809120621] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2020] [Revised: 02/15/2021] [Accepted: 06/13/2021] [Indexed: 12/12/2022]
Abstract
Human Central Nervous System (CNS) is the complex part of the human body, which regulates multiple cellular and molecular events taking place simultaneously. Parkinsons Disease (PD) is the second most common neurodegenerative disease after Alzheimer's disease (AD). The pathological hallmarks of PD are loss of dopaminergic neurons in the substantianigra (SN) pars compacta (SNpc) and accumulation of misfolded α-synuclein, in intra-cytoplasmic inclusions called Lewy bodies (LBs). So far, there is no cure for PD, due to the complexities of molecular mechanisms and events taking place during the pathogenesis of PD. Drosophila melanogaster is an appropriate model organism to unravel the pathogenicity not only behind PD but also other NDs. In this context as numerous biological functions are preserved between Drosophila and humans. Apart from sharing 75% of human disease-causing genes homolog in Drosophila, behavioral responses like memory-based tests, negative geotaxis, courtship and mating are also well studied. The genetic, as well as environmental factors, can be studied in Drosophila to understand the geneenvironment interactions behind the disease condition. Through genetic manipulation, mutant flies can be generated harboring human orthologs, which can prove to be an excellent model to understand the effect of the mutant protein on the pathogenicity of NDs.
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Affiliation(s)
- Rahul
- Drosophila Transgenic Laboratory, Section of Genetics, Department of Zoology, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, 202002, Uttar Pradesh,India
| | - Yasir Hasan Siddique
- Drosophila Transgenic Laboratory, Section of Genetics, Department of Zoology, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, 202002, Uttar Pradesh,India
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20
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Abstract
In this review, we highlight sources of alcohols in nature, as well as the behavioral and ecological roles that these fermentation cues play in the short lifespan of Drosophila melanogaster. With a focus on neuroethology, we describe the olfactory detection of alcohol as well as ensuing neural signaling within the brain of the fly. We proceed to explain the plethora of behaviors related to alcohol, including attraction, feeding, and oviposition, as well as general effects on aggression and courtship. All of these behaviors are shaped by physiological state and social contexts. In a comparative perspective, we also discuss inter- and intraspecies differences related to alcohol tolerance and metabolism. Lastly, we provide corollaries with other dipteran and coleopteran insect species that also have olfactory systems attuned to ethanol detection and describe ecological and evolutionary directions for further studies of the natural history of alcohol and the fly.
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Affiliation(s)
- Ian W Keesey
- School of Biological Sciences, University of Nebraska, Lincoln, Nebraska 68588, USA;
- Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, D-07745 Jena, Germany;
| | - Bill S Hansson
- Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, D-07745 Jena, Germany;
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21
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Sareen PF, McCurdy LY, Nitabach MN. A neuronal ensemble encoding adaptive choice during sensory conflict in Drosophila. Nat Commun 2021; 12:4131. [PMID: 34226544 PMCID: PMC8257655 DOI: 10.1038/s41467-021-24423-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Accepted: 06/18/2021] [Indexed: 01/02/2023] Open
Abstract
Feeding decisions are fundamental to survival, and decision making is often disrupted in disease. Here, we show that neural activity in a small population of neurons projecting to the fan-shaped body higher-order central brain region of Drosophila represents food choice during sensory conflict. We found that food deprived flies made tradeoffs between appetitive and aversive values of food. We identified an upstream neuropeptidergic and dopaminergic network that relays internal state and other decision-relevant information to a specific subset of fan-shaped body neurons. These neurons were strongly inhibited by the taste of the rejected food choice, suggesting that they encode behavioral food choice. Our findings reveal that fan-shaped body taste responses to food choices are determined not only by taste quality, but also by previous experience (including choice outcome) and hunger state, which are integrated in the fan-shaped body to encode the decision before relay to downstream motor circuits for behavioral implementation.
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Affiliation(s)
- Preeti F Sareen
- Department of Cellular and Molecular Physiology, Yale University, New Haven, CT, USA
| | - Li Yan McCurdy
- Department of Cellular and Molecular Physiology, Yale University, New Haven, CT, USA
- Interdepartmental Neuroscience Program, Yale University, New Haven, CT, USA
| | - Michael N Nitabach
- Department of Cellular and Molecular Physiology, Yale University, New Haven, CT, USA.
- Department of Genetics, Yale University, New Haven, CT, USA.
- Department of Neuroscience, Yale University, New Haven, CT, USA.
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22
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Durkin SM, Chakraborty M, Abrieux A, Lewald KM, Gadau A, Svetec N, Peng J, Kopyto M, Langer CB, Chiu JC, Emerson JJ, Zhao L. Behavioral and Genomic Sensory Adaptations Underlying the Pest Activity of Drosophila suzukii. Mol Biol Evol 2021; 38:2532-2546. [PMID: 33586767 PMCID: PMC8136512 DOI: 10.1093/molbev/msab048] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Studying how novel phenotypes originate and evolve is fundamental to the field of evolutionary biology as it allows us to understand how organismal diversity is generated and maintained. However, determining the basis of novel phenotypes is challenging as it involves orchestrated changes at multiple biological levels. Here, we aim to overcome this challenge by using a comparative species framework combining behavioral, gene expression, and genomic analyses to understand the evolutionary novel egg-laying substrate-choice behavior of the invasive pest species Drosophila suzukii. First, we used egg-laying behavioral assays to understand the evolution of ripe fruit oviposition preference in D. suzukii compared with closely related species D. subpulchrella and D. biarmipes as well as D. melanogaster. We show that D. subpulchrella and D. biarmipes lay eggs on both ripe and rotten fruits, suggesting that the transition to ripe fruit preference was gradual. Second, using two-choice oviposition assays, we studied how D. suzukii, D. subpulchrella, D. biarmipes, and D. melanogaster differentially process key sensory cues distinguishing ripe from rotten fruit during egg-laying. We found that D. suzukii's preference for ripe fruit is in part mediated through a species-specific preference for stiff substrates. Last, we sequenced and annotated a high-quality genome for D. subpulchrella. Using comparative genomic approaches, we identified candidate genes involved in D. suzukii's ability to seek out and target ripe fruits. Our results provide detail to the stepwise evolution of pest activity in D. suzukii, indicating important cues used by this species when finding a host, and the molecular mechanisms potentially underlying their adaptation to a new ecological niche.
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Affiliation(s)
- Sylvia M Durkin
- Laboratory of Evolutionary Genetics and Genomics, The Rockefeller University, New York, NY, USA
- Department of Integrative Biology and Museum of Vertebrate Zoology, University of California, Berkeley, Berkeley, CA, USA
| | - Mahul Chakraborty
- Department of Ecology and Evolutionary Biology, University of California, Irvine, CA, USA
| | - Antoine Abrieux
- Department of Entomology and Nematology, College of Agricultural and Environmental Sciences, University of California, Davis, Davis, CA, USA
| | - Kyle M Lewald
- Department of Entomology and Nematology, College of Agricultural and Environmental Sciences, University of California, Davis, Davis, CA, USA
| | - Alice Gadau
- Laboratory of Evolutionary Genetics and Genomics, The Rockefeller University, New York, NY, USA
| | - Nicolas Svetec
- Laboratory of Evolutionary Genetics and Genomics, The Rockefeller University, New York, NY, USA
| | - Junhui Peng
- Laboratory of Evolutionary Genetics and Genomics, The Rockefeller University, New York, NY, USA
| | - Miriam Kopyto
- Laboratory of Evolutionary Genetics and Genomics, The Rockefeller University, New York, NY, USA
| | - Christopher B Langer
- Laboratory of Evolutionary Genetics and Genomics, The Rockefeller University, New York, NY, USA
| | - Joanna C Chiu
- Department of Entomology and Nematology, College of Agricultural and Environmental Sciences, University of California, Davis, Davis, CA, USA
| | - J J Emerson
- Department of Ecology and Evolutionary Biology, University of California, Irvine, CA, USA
| | - Li Zhao
- Laboratory of Evolutionary Genetics and Genomics, The Rockefeller University, New York, NY, USA
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23
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Kanno M, Hiramatsu S, Kondo S, Tanimoto H, Ichinose T. Voluntary intake of psychoactive substances is regulated by the dopamine receptor Dop1R1 in Drosophila. Sci Rep 2021; 11:3432. [PMID: 33564023 PMCID: PMC7873259 DOI: 10.1038/s41598-021-82813-0] [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: 08/12/2020] [Accepted: 01/21/2021] [Indexed: 11/09/2022] Open
Abstract
Dysregulated motivation to consume psychoactive substances leads to addictive behaviors that often result in serious health consequences. Understanding the neuronal mechanisms that drive drug consumption is crucial for developing new therapeutic strategies. The fruit fly Drosophila melanogaster offers a unique opportunity to approach this problem with a battery of sophisticated neurogenetic tools available, but how they consume these drugs remains largely unknown. Here, we examined drug self-administration behavior of Drosophila and the underlying neuronal mechanisms. We measured the preference of flies for five different psychoactive substances using a two-choice feeding assay and monitored its long-term changes. We found that flies show acute preference for ethanol and methamphetamine, but not for cocaine, caffeine or morphine. Repeated intake of ethanol, but not methamphetamine, increased over time. Preference for methamphetamine and the long-term escalation of ethanol preference required the dopamine receptor Dop1R1 in the mushroom body. The protein level of Dop1R1 increased after repeated intake of ethanol, but not methamphetamine, which correlates with the acquired preference. Genetic overexpression of Dop1R1 enhanced ethanol preference. These results reveal a striking diversity of response to individual drugs in the fly and the role of dopamine signaling and its plastic changes in controlling voluntary intake of drugs.
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Affiliation(s)
- Mai Kanno
- Graduate School of Life Sciences, Tohoku University, Sendai, 980-8577, Japan
| | - Shun Hiramatsu
- Graduate School of Life Sciences, Tohoku University, Sendai, 980-8577, Japan
| | - Shu Kondo
- Invertebrate Genetics Laboratory, National Institute of Genetics, Mishima, 411-8540, Japan
| | - Hiromu Tanimoto
- Graduate School of Life Sciences, Tohoku University, Sendai, 980-8577, Japan
| | - Toshiharu Ichinose
- Graduate School of Life Sciences, Tohoku University, Sendai, 980-8577, Japan. .,Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, Sendai, 980-8578, Japan. .,Center for Transdisciplinary Research, Niigata University, Niigata, 950-2181, Japan. .,Department of Neuropharmacology, Nagoya City University, Nagoya, 467-8603, Japan.
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24
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Siju KP, De Backer JF, Grunwald Kadow IC. 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: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [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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Affiliation(s)
- K. P. Siju
- School of Life Sciences, Department of Molecular Life Sciences, Technical University of Munich, 85354 Freising, Germany
| | - Jean-Francois De Backer
- School of Life Sciences, Department of Molecular Life Sciences, Technical University of Munich, 85354 Freising, Germany
| | - Ilona C. Grunwald Kadow
- School of Life Sciences, Department of Molecular Life Sciences, Technical University of Munich, 85354 Freising, Germany
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25
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Chvilicek MM, Titos I, Rothenfluh A. The Neurotransmitters Involved in Drosophila Alcohol-Induced Behaviors. Front Behav Neurosci 2020; 14:607700. [PMID: 33384590 PMCID: PMC7770116 DOI: 10.3389/fnbeh.2020.607700] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 11/23/2020] [Indexed: 12/18/2022] Open
Abstract
Alcohol is a widely used and abused substance with numerous negative consequences for human health and safety. Historically, alcohol's widespread, non-specific neurobiological effects have made it a challenge to study in humans. Therefore, model organisms are a critical tool for unraveling the mechanisms of alcohol action and subsequent effects on behavior. Drosophila melanogaster is genetically tractable and displays a vast behavioral repertoire, making it a particularly good candidate for examining the neurobiology of alcohol responses. In addition to being experimentally amenable, Drosophila have high face and mechanistic validity: their alcohol-related behaviors are remarkably consistent with humans and other mammalian species, and they share numerous conserved neurotransmitters and signaling pathways. Flies have a long history in alcohol research, which has been enhanced in recent years by the development of tools that allow for manipulating individual Drosophila neurotransmitters. Through advancements such as the GAL4/UAS system and CRISPR/Cas9 mutagenesis, investigation of specific neurotransmitters in small subsets of neurons has become ever more achievable. In this review, we describe recent progress in understanding the contribution of seven neurotransmitters to fly behavior, focusing on their roles in alcohol response: dopamine, octopamine, tyramine, serotonin, glutamate, GABA, and acetylcholine. We chose these small-molecule neurotransmitters due to their conservation in mammals and their importance for behavior. While neurotransmitters like dopamine and octopamine have received significant research emphasis regarding their contributions to behavior, others, like glutamate, GABA, and acetylcholine, remain relatively unexplored. Here, we summarize recent genetic and behavioral findings concerning these seven neurotransmitters and their roles in the behavioral response to alcohol, highlighting the fitness of the fly as a model for human alcohol use.
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Affiliation(s)
- Maggie M. Chvilicek
- Department of Psychiatry, University of Utah, Salt Lake City, UT, United States
- Molecular Medicine Program, University of Utah, Salt Lake City, UT, United States
- Neuroscience Graduate Program, University of Utah, Salt Lake City, UT, United States
| | - Iris Titos
- Molecular Medicine Program, University of Utah, Salt Lake City, UT, United States
| | - Adrian Rothenfluh
- Department of Psychiatry, University of Utah, Salt Lake City, UT, United States
- Molecular Medicine Program, University of Utah, Salt Lake City, UT, United States
- Neuroscience Graduate Program, University of Utah, Salt Lake City, UT, United States
- Department of Neurobiology and Anatomy, University of Utah, Salt Lake City, UT, United States
- Department of Human Genetics, University of Utah, Salt Lake City, UT, United States
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26
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Park A, Tran T, Scheuermann EA, Smith DP, Atkinson NS. Alcohol potentiates a pheromone signal in flies. eLife 2020; 9:59853. [PMID: 33141025 PMCID: PMC7671682 DOI: 10.7554/elife.59853] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Accepted: 11/01/2020] [Indexed: 01/29/2023] Open
Abstract
For decades, numerous researchers have documented the presence of the fruit fly or Drosophila melanogaster on alcohol-containing food sources. Although fruit flies are a common laboratory model organism of choice, there is relatively little understood about the ethological relationship between flies and ethanol. In this study, we find that when male flies inhabit ethanol-containing food substrates they become more aggressive. We identify a possible mechanism for this behavior. The odor of ethanol potentiates the activity of sensory neurons in response to an aggression-promoting pheromone. Finally, we observed that the odor of ethanol also promotes attraction to a food-related citrus odor. Understanding how flies interact with the complex natural environment they inhabit can provide valuable insight into how different natural stimuli are integrated to promote fundamental behaviors.
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Affiliation(s)
- Annie Park
- Department of Neuroscience and Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, United States
| | - Tracy Tran
- Department of Neuroscience and Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, United States
| | - Elizabeth A Scheuermann
- Department of Pharmacology and Neuroscience, University of Texas Southwestern Medical Center, Dallas, United States
| | - Dean P Smith
- Department of Pharmacology and Neuroscience, University of Texas Southwestern Medical Center, Dallas, United States
| | - Nigel S Atkinson
- Department of Neuroscience and Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, United States
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27
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Siju KP, Štih V, Aimon S, Gjorgjieva J, Portugues R, Grunwald Kadow IC. Valence and State-Dependent Population Coding in Dopaminergic Neurons in the Fly Mushroom Body. Curr Biol 2020; 30:2104-2115.e4. [PMID: 32386530 DOI: 10.1016/j.cub.2020.04.037] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 03/13/2020] [Accepted: 04/16/2020] [Indexed: 11/26/2022]
Abstract
Neuromodulation permits flexibility of synapses, neural circuits, and ultimately behavior. One neuromodulator, dopamine, has been studied extensively in its role as a reward signal during learning and memory across animal species. Newer evidence suggests that dopaminergic neurons (DANs) can modulate sensory perception acutely, thereby allowing an animal to adapt its behavior and decision making to its internal and behavioral state. In addition, some data indicate that DANs are not homogeneous but rather convey different types of information as a heterogeneous population. We have investigated DAN population activity and how it could encode relevant information about sensory stimuli and state by taking advantage of the confined anatomy of DANs innervating the mushroom body (MB) of the fly Drosophila melanogaster. Using in vivo calcium imaging and a custom 3D image registration method, we found that the activity of the population of MB DANs encodes innate valence information of an odor or taste as well as the physiological state of the animal. Furthermore, DAN population activity is strongly correlated with movement, consistent with a role of dopamine in conveying behavioral state to the MB. Altogether, our data and analysis suggest that DAN population activities encode innate odor and taste valence, movement, and physiological state in a MB-compartment-specific manner. We propose that dopamine shapes innate perception through combinatorial population coding of sensory valence, physiological, and behavioral context.
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Affiliation(s)
- K P Siju
- TUM School of Life Sciences, Technical University of Munich, 85354 Freising, Germany
| | - Vilim Štih
- Sensorimotor Control Group, Max Planck Institute of Neurobiology, 82152 Martinsried, Germany
| | - Sophie Aimon
- TUM School of Life Sciences, Technical University of Munich, 85354 Freising, Germany
| | - Julijana Gjorgjieva
- TUM School of Life Sciences, Technical University of Munich, 85354 Freising, Germany; Computation in Neural Circuits Group, Max Planck Institute for Brain Research, 60438 Frankfurt am Main, Germany
| | - Ruben Portugues
- Sensorimotor Control Group, Max Planck Institute of Neurobiology, 82152 Martinsried, Germany; Institute of Neuroscience, Technical University of Munich, 80802 Munich, Germany; Munich Cluster for Systems Neurology (SyNergy), 80802 Munich, Germany
| | - Ilona C Grunwald Kadow
- TUM School of Life Sciences, Technical University of Munich, 85354 Freising, Germany; ZIEL-Institute of Food and Health, Technical University of Munich, 85354 Freising, Germany.
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A Feedforward Circuit Regulates Action Selection of Pre-mating Courtship Behavior in Female Drosophila. Curr Biol 2020; 30:396-407.e4. [PMID: 31902724 DOI: 10.1016/j.cub.2019.11.065] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 10/21/2019] [Accepted: 11/21/2019] [Indexed: 01/01/2023]
Abstract
In the early phase of courtship, female fruit flies exhibit an acute rejection response to avoid unfavorable mating. This pre-mating rejection response is evolutionarily paralleled across species, but the molecular and neuronal basis of that behavior is unclear. Here, we show that a putative incoherent feedforward circuit comprising ellipsoid body neurons, cholinergic R4d, and its repressor GABAergic R2/R4m neurons regulates the pre-mating rejection response in the virgin female Drosophila melanogaster. Both R4d and R2/R4m are positively regulated, via specific dopamine receptors, by a subset of neurons in the dopaminergic PPM3 cluster. Genetic deprivation of GABAergic signal via GABAA receptor RNA interference in this circuit induces a massive rejection response, whereas activation of GABAergic R2/R4m or suppression of cholinergic R4d increases receptivity. Moreover, glutamatergic signaling via N-methyl-d-aspartate receptors induces NO-mediated retrograde regulation potentially from R4d to R2/R4m, likely providing flexible control of the behavioral switching from rejection to acceptance. Our study elucidates the molecular and neural mechanisms regulating the behavioral selection process of the pre-mating female.
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Scholz H. Unraveling the Mechanisms of Behaviors Associated With AUDs Using Flies and Worms. Alcohol Clin Exp Res 2019; 43:2274-2284. [PMID: 31529787 DOI: 10.1111/acer.14199] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Accepted: 09/11/2019] [Indexed: 12/11/2022]
Abstract
Alcohol use disorders (AUDs) are very common worldwide and negatively affect both individuals and societies. To understand how normal behavior turns into uncontrollable use of alcohol, several approaches have been utilized in the last decades. However, we still do not completely understand how AUDs evolve or how they are maintained in the brains of affected individuals. In addition, efficient and effective treatment is still in need of development. This review focuses on alternative approaches developed over the last 20 years using Drosophila melanogaster (Drosophila) and Caenorhabditis elegans (C. elegans) as genetic model systems to determine the mechanisms underlying the action of ethanol (EtOH) and behaviors associated with AUDs. All the results and insights of studies over the last 20 years cannot be comprehensively summarized. Thus, a few prominent examples are provided highlighting the principles of the genes and mechanisms that have been uncovered and are involved in the action of EtOH at the cellular level. In addition, examples are provided of the genes and mechanisms that regulate behaviors relevant to acquiring and maintaining excessive alcohol intake, such as decision making, reward and withdrawal, and/or relapse regulation. How the insight gained from the results of Drosophila and C. elegans models can be translated to higher organisms, such as rodents and/or humans, is discussed, as well as whether these insights have any relevance or impact on our understanding of the mechanisms underlying AUDs in humans. Finally, future directions are presented that might facilitate the identification of drugs to treat AUDs.
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Affiliation(s)
- Henrike Scholz
- From the, Department of Biology, Institute for Zoology, Albertus-Magnus University of Cologne, Cologne, Germany
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30
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Wu SF, Ja YL, Zhang YJ, Yang CH. Sweet neurons inhibit texture discrimination by signaling TMC-expressing mechanosensitive neurons in Drosophila. eLife 2019; 8:46165. [PMID: 31184585 PMCID: PMC6559806 DOI: 10.7554/elife.46165] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Accepted: 05/30/2019] [Indexed: 11/13/2022] Open
Abstract
Integration of stimuli of different modalities is an important but incompletely understood process during decision making. Here, we show that Drosophila are capable of integrating mechanosensory and chemosensory information of choice options when deciding where to deposit their eggs. Specifically, females switch from preferring the softer option for egg-laying when both options are sugar free to being indifferent between them when both contain sucrose. Such sucrose-induced indifference between options of different hardness requires functional sweet neurons, and, curiously, the Transmembrane Channel-like (TMC)-expressing mechanosensitive neurons that have been previously shown to promote discrimination of substrate hardness during feeding. Further, axons of sweet neurons directly contact axons of TMC-expressing neurons in the brain and stimulation of sweet neurons increases Ca2+ influx into axons of TMC-expressing neurons. These results uncover one mechanism by which Drosophila integrate taste and tactile information when deciding where to deposit their eggs and reveal that TMC-expressing neurons play opposing roles in hardness discrimination in two different decisions.
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Affiliation(s)
- Shun-Fan Wu
- State & Local Joint Engineering Research Center of Green Pesticide Invention and Application, College of Plant Protection, Nanjing Agricultural University, Nanjing, China.,Department of Neurobiology, Duke University, Durham, United States
| | - Ya-Long Ja
- State & Local Joint Engineering Research Center of Green Pesticide Invention and Application, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Yi-Jie Zhang
- State & Local Joint Engineering Research Center of Green Pesticide Invention and Application, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Chung-Hui Yang
- Department of Neurobiology, Duke University, Durham, United States
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31
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Cury KM, Prud'homme B, Gompel N. A short guide to insect oviposition: when, where and how to lay an egg. J Neurogenet 2019; 33:75-89. [PMID: 31164023 DOI: 10.1080/01677063.2019.1586898] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Egg-laying behavior is one of the most important aspects of female behavior, and has a profound impact on the fitness of a species. As such, it is controlled by several layers of regulation. Here, we review recent advances in our understanding of insect neural circuits that control when, where and how to lay an egg. We also outline outstanding open questions about the control of egg-laying decisions, and speculate on the possible neural underpinnings that can drive the diversification of oviposition behaviors through evolution.
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Affiliation(s)
- Kevin M Cury
- a Department of Neuroscience and the Mortimer B. Zuckerman Mind Brain Behavior Institute , Columbia University , New York , NY , USA
| | - Benjamin Prud'homme
- b Aix Marseille Université, CNRS , Institut de Biologie du Développement de Marseille (IBDM) , Marseille , France
| | - Nicolas Gompel
- c Fakultät für Biologie, Biozentrum , Ludwig-Maximilians Universität München , Munich , Germany
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32
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Bräcker LB, Schmid CA, Bolini VA, Holz CA, Prud'homme B, Sirota A, Gompel N. Quantitative and Discrete Evolutionary Changes in the Egg-Laying Behavior of Single Drosophila Females. Front Behav Neurosci 2019; 13:118. [PMID: 31191270 PMCID: PMC6549446 DOI: 10.3389/fnbeh.2019.00118] [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: 03/01/2019] [Accepted: 05/16/2019] [Indexed: 12/22/2022] Open
Abstract
How a nervous system assembles and coordinates a suite of elementary behavioral steps into a complex behavior is not well understood. While often presented as a stereotyped sequence of events, even extensively studied behaviors such as fly courtship are rarely a strict repetition of the same steps in a predetermined sequence in time. We are focusing on oviposition, the act of laying an egg, in flies of the genus Drosophila to describe the elementary behavioral steps or microbehaviors that a single female fly undertakes prior to and during egg laying. We have analyzed the hierarchy and relationships in time of these microbehaviors in three closely related Drosophila species with divergent egg-laying preferences and uncovered cryptic differences in their behavioral patterns. Using high-speed imaging, we quantified in depth the oviposition behavior of single females of Drosophila suzukii, Drosophila biarmipes and Drosophila melanogaster in a novel behavioral assay. By computing transitions between microbehaviors, we identified a common ethogram structure underlying oviposition of all three species. Quantifying parameters such as relative time spent on a microbehavior and its average duration, however, revealed clear differences between species. In addition, we examined the temporal dynamics and probability of transitions to different microbehaviors relative to a central event of oviposition, ovipositor contact. Although the quantitative analysis highlights behavioral variability across flies, it reveals some interesting trends for each species in the mode of substrate sampling, as well as possible evolutionary differences. Larger datasets derived from automated video annotation will overcome this paucity of data in the future, and use the same framework to reappraise these observed differences. Our study reveals a common architecture to the oviposition ethogram of three Drosophila species, indicating its ancestral state. It also indicates that Drosophila suzukii’s behavior departs quantitatively and qualitatively from that of the outgroup species, in line with its known divergent ethology. Together, our results illustrate how a global shift in ethology breaks down in the quantitative reorganization of the elementary steps underlying a complex behavior.
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Affiliation(s)
- Lasse B Bräcker
- Fakultät für Biologie, Biozentrum, Ludwig-Maximilians Universität München, Munich, Germany
| | - Christian A Schmid
- Fakultät für Biologie, Biozentrum, Ludwig-Maximilians Universität München, Munich, Germany
| | - Verena A Bolini
- Fakultät für Biologie, Biozentrum, Ludwig-Maximilians Universität München, Munich, Germany
| | - Claudia A Holz
- Fakultät für Biologie, Biozentrum, Ludwig-Maximilians Universität München, Munich, Germany
| | - Benjamin Prud'homme
- Aix-Marseille Université, CNRS, IBDM, Institut de Biologie du Développement de Marseille, Campus de Luminy Case 907, Marseille, France
| | - Anton Sirota
- Bernstein Center for Computational Neuroscience Munich, Faculty of Medicine, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany
| | - Nicolas Gompel
- Fakultät für Biologie, Biozentrum, Ludwig-Maximilians Universität München, Munich, Germany
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33
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Haberkern H, Basnak MA, Ahanonu B, Schauder D, Cohen JD, Bolstad M, Bruns C, Jayaraman V. Visually Guided Behavior and Optogenetically Induced Learning in Head-Fixed Flies Exploring a Virtual Landscape. Curr Biol 2019; 29:1647-1659.e8. [DOI: 10.1016/j.cub.2019.04.033] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2018] [Revised: 03/22/2019] [Accepted: 04/11/2019] [Indexed: 11/28/2022]
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34
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Engel GL, Taber K, Vinton E, Crocker AJ. Studying alcohol use disorder using Drosophila melanogaster in the era of 'Big Data'. BEHAVIORAL AND BRAIN FUNCTIONS : BBF 2019; 15:7. [PMID: 30992041 PMCID: PMC6469124 DOI: 10.1186/s12993-019-0159-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Accepted: 04/04/2019] [Indexed: 02/08/2023]
Abstract
Our understanding of the networks of genes and protein functions involved in Alcohol Use Disorder (AUD) remains incomplete, as do the mechanisms by which these networks lead to AUD phenotypes. The fruit fly (Drosophila melanogaster) is an efficient model for functional and mechanistic characterization of the genes involved in alcohol behavior. The fly offers many advantages as a model organism for investigating the molecular and cellular mechanisms of alcohol-related behaviors, and for understanding the underlying neural circuitry driving behaviors, such as locomotor stimulation, sedation, tolerance, and appetitive (reward) learning and memory. Fly researchers are able to use an extensive variety of tools for functional characterization of gene products. To understand how the fly can guide our understanding of AUD in the era of Big Data we will explore these tools, and review some of the gene networks identified in the fly through their use, including chromatin-remodeling, glial, cellular stress, and innate immunity genes. These networks hold great potential as translational drug targets, making it prudent to conduct further research into how these gene mechanisms are involved in alcohol behavior.
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Affiliation(s)
- Gregory L. Engel
- Department of Psychological Sciences, Castleton University, Castleton, VT 05735 USA
| | - Kreager Taber
- Program in Neuroscience, Middlebury College, Middlebury, VT 05753 USA
| | - Elizabeth Vinton
- Program in Neuroscience, Middlebury College, Middlebury, VT 05753 USA
| | - Amanda J. Crocker
- Program in Neuroscience, Middlebury College, Middlebury, VT 05753 USA
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35
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Agrawal P, Chung P, Heberlein U, Kent C. Enabling cell-type-specific behavioral epigenetics in Drosophila: a modified high-yield INTACT method reveals the impact of social environment on the epigenetic landscape in dopaminergic neurons. BMC Biol 2019; 17:30. [PMID: 30967153 PMCID: PMC6456965 DOI: 10.1186/s12915-019-0646-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Accepted: 03/07/2019] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Epigenetic mechanisms play fundamental roles in brain function and behavior and stressors such as social isolation can alter animal behavior via epigenetic mechanisms. However, due to cellular heterogeneity, identifying cell-type-specific epigenetic changes in the brain is challenging. Here, we report the first use of a modified isolation of nuclei tagged in specific cell type (INTACT) method in behavioral epigenetics of Drosophila melanogaster, a method we call mini-INTACT. RESULTS Using ChIP-seq on mini-INTACT purified dopaminergic nuclei, we identified epigenetic signatures in socially isolated and socially enriched Drosophila males. Social experience altered the epigenetic landscape in clusters of genes involved in transcription and neural function. Some of these alterations could be predicted by expression changes of four transcription factors and the prevalence of their binding sites in several clusters. These transcription factors were previously identified as activity-regulated genes, and their knockdown in dopaminergic neurons reduced the effects of social experience on sleep. CONCLUSIONS Our work enables the use of Drosophila as a model for cell-type-specific behavioral epigenetics and establishes that social environment shifts the epigenetic landscape in dopaminergic neurons. Four activity-related transcription factors are required in dopaminergic neurons for the effects of social environment on sleep.
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Affiliation(s)
- Pavan Agrawal
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA.
| | - Phuong Chung
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Ulrike Heberlein
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Clement Kent
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA.
- Department of Biology, York University, Toronto, Canada.
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36
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Petruccelli E, Kaun KR. Insights from intoxicated Drosophila. Alcohol 2019; 74:21-27. [PMID: 29980341 DOI: 10.1016/j.alcohol.2018.03.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Revised: 03/14/2018] [Accepted: 03/14/2018] [Indexed: 01/31/2023]
Abstract
Our understanding of alcohol use disorder (AUD), particularly alcohol's effects on the nervous system, has unquestionably benefited from the use of model systems such as Drosophila melanogaster. Here, we briefly introduce the use of flies in alcohol research, and highlight the genetic accessibility and neurobiological contribution that flies have made to our understanding of AUD. Future fly research offers unique opportunities for addressing unresolved questions in the alcohol field, such as the neuromolecular and circuit basis for cravings and alcohol-induced neuroimmune dysfunction. This review strongly advocates for interdisciplinary approaches and translational collaborations with the united goal of confronting the major health problems associated with alcohol abuse and addiction.
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37
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Lamaze A, Krätschmer P, Chen KF, Lowe S, Jepson JE. A Wake-Promoting Circadian Output Circuit in Drosophila. Curr Biol 2018; 28:3098-3105.e3. [DOI: 10.1016/j.cub.2018.07.024] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Revised: 05/24/2018] [Accepted: 07/09/2018] [Indexed: 11/17/2022]
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38
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Zhou Y, Smith BH, Sharpee TO. Hyperbolic geometry of the olfactory space. SCIENCE ADVANCES 2018; 4:eaaq1458. [PMID: 30167457 PMCID: PMC6114987 DOI: 10.1126/sciadv.aaq1458] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 07/19/2018] [Indexed: 05/20/2023]
Abstract
In the natural environment, the sense of smell, or olfaction, serves to detect toxins and judge nutritional content by taking advantage of the associations between compounds as they are created in biochemical reactions. This suggests that the nervous system can classify odors based on statistics of their co-occurrence within natural mixtures rather than from the chemical structures of the ligands themselves. We show that this statistical perspective makes it possible to map odors to points in a hyperbolic space. Hyperbolic coordinates have a long but often underappreciated history of relevance to biology. For example, these coordinates approximate the distance between species computed along dendrograms and, more generally, between points within hierarchical tree-like networks. We find that both natural odors and human perceptual descriptions of smells can be described using a three-dimensional hyperbolic space. This match in geometries can avoid distortions that would otherwise arise when mapping odors to perception.
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Affiliation(s)
- Yuansheng Zhou
- Computational Neurobiology Laboratory, Salk Institute for Biological Studies, La Jolla, CA 92037, USA
- Division of Biological Sciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - Brian H. Smith
- School of Life Sciences, Arizona State University, Tempe, AZ 85287, USA
| | - Tatyana O. Sharpee
- Computational Neurobiology Laboratory, Salk Institute for Biological Studies, La Jolla, CA 92037, USA
- Department of Physics, University of California, San Diego, La Jolla, CA 92093, USA
- Corresponding author.
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39
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Rosenthal GG. Evaluation and hedonic value in mate choice. Curr Zool 2018; 64:485-492. [PMID: 30108629 PMCID: PMC6084558 DOI: 10.1093/cz/zoy054] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Accepted: 06/27/2018] [Indexed: 01/30/2023] Open
Abstract
Mating preferences can show extreme variation within and among individuals even when sensory inputs are conserved. This variation is a result of changes associated with evaluative mechanisms that assign positive, neutral, or negative hedonic value to stimuli—that is, label them as attractive, uninteresting, or unattractive. There is widespread behavioral evidence for differences in genes, environmental cues, or social experience leading to marked changes in the hedonic value of stimuli. Evaluation is accomplished through an array of mechanisms that are readily modifiable through genetic changes or environmental inputs, and that may often result in the rapid acquisition or loss of behavioral preferences. Reversals in preference arising from “flips” in hedonic value may be quite common. Incorporating such discontinuous changes into models of preference evolution may illuminate our understanding of processes like trait diversification, sexual conflict, and sympatric speciation.
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Affiliation(s)
- Gil G Rosenthal
- Texas A&M University, College Station, TX, USA.,Centro de Investigaciones Científicas de la Huastecas "Aguazarca", Università degli Studi di Torino, Italy
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40
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Claßen G, Scholz H. Octopamine Shifts the Behavioral Response From Indecision to Approach or Aversion in Drosophila melanogaster. Front Behav Neurosci 2018; 12:131. [PMID: 30018540 PMCID: PMC6037846 DOI: 10.3389/fnbeh.2018.00131] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Accepted: 06/11/2018] [Indexed: 11/13/2022] Open
Abstract
Animals must make constant decisions whether to respond to external sensory stimuli or not to respond. The activation of positive and/or negative reinforcers might bias the behavioral response towards approach or aversion. To analyze whether the activation of the octopaminergic neurotransmitter system can shift the decision between two identical odor sources, we active in Drosophila melanogaster different sets of octopaminergic neurons using optogenetics and analyze the choice of the flies using a binary odor trap assay. We show that the release of octopamine from a set of neurons and not acetylcholine acts as positive reinforcer for one food odor source resulting in attraction. The activation of a subset of these neurons causes the opposite behavior and results in aversion. This aversion is due to octopamine release and not tyramine, since in Tyramine-β-hydroxylase mutants (Tβh) lacking octopamine, the aversion is suppressed. We show that when given the choice between two different attractive food odor sources the activation of the octopaminergic neurotransmitter system switches the attraction for ethanol-containing food odor to a less attractive food odor. Consistent with the requirement for octopamine in biasing the behavioral outcome, Tβh mutants fail to switch their attraction. The execution of attraction does not require octopamine but rather initiation of the behavior or a switch of the behavioral response. The attraction to ethanol also depends on octopamine. Pharmacological increases in octopamine signaling in Tβh mutants increase ethanol attraction and blocking octopamine receptor function reduces ethanol attraction. Taken together, octopamine in the central brain orchestrates behavioral outcomes by biasing the decision of the animal towards food odors. This finding might uncover a basic principle of how octopamine gates behavioral outcomes in the brain.
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Affiliation(s)
- Gerbera Claßen
- Department of Biology, Institute for Zoology, Biocenter, Albertus-Magnus University of Cologne, Cologne, Germany
| | - Henrike Scholz
- Department of Biology, Institute for Zoology, Biocenter, Albertus-Magnus University of Cologne, Cologne, Germany
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41
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Deciphering Drosophila female innate behaviors. Curr Opin Neurobiol 2018; 52:139-148. [PMID: 29940518 DOI: 10.1016/j.conb.2018.06.005] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 06/09/2018] [Indexed: 01/08/2023]
Abstract
Innate responses are often sexually dimorphic. Studies of female specific behaviors have remained niche, but the focus is changing as illustrated by the recent progress in understanding the female courtship responses and egg-laying decisions. In this review, we will cover our current knowledge about female behaviors in these two specific contexts. Recent studies elucidate on how females process the courtship song. They also show that egg-laying decisions are extremely complex, requiring the assessment of food, microbial, predator and social cues. Study of female responses will improve our understanding of how a nervous system processes different challenges.
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Big Lessons from Tiny Flies: Drosophila melanogaster as a Model to Explore Dysfunction of Dopaminergic and Serotonergic Neurotransmitter Systems. Int J Mol Sci 2018; 19:ijms19061788. [PMID: 29914172 PMCID: PMC6032372 DOI: 10.3390/ijms19061788] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 06/11/2018] [Accepted: 06/13/2018] [Indexed: 12/31/2022] Open
Abstract
The brain of Drosophila melanogaster is comprised of some 100,000 neurons, 127 and 80 of which are dopaminergic and serotonergic, respectively. Their activity regulates behavioral functions equivalent to those in mammals, e.g., motor activity, reward and aversion, memory formation, feeding, sexual appetite, etc. Mammalian dopaminergic and serotonergic neurons are known to be heterogeneous. They differ in their projections and in their gene expression profile. A sophisticated genetic tool box is available, which allows for targeting virtually any gene with amazing precision in Drosophila melanogaster. Similarly, Drosophila genes can be replaced by their human orthologs including disease-associated alleles. Finally, genetic manipulation can be restricted to single fly neurons. This has allowed for addressing the role of individual neurons in circuits, which determine attraction and aversion, sleep and arousal, odor preference, etc. Flies harboring mutated human orthologs provide models which can be interrogated to understand the effect of the mutant protein on cell fate and neuronal connectivity. These models are also useful for proof-of-concept studies to examine the corrective action of therapeutic strategies. Finally, experiments in Drosophila can be readily scaled up to an extent, which allows for drug screening with reasonably high throughput.
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Quan AS, Eisen MB. The ecology of the Drosophila-yeast mutualism in wineries. PLoS One 2018; 13:e0196440. [PMID: 29768432 PMCID: PMC5955509 DOI: 10.1371/journal.pone.0196440] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Accepted: 04/12/2018] [Indexed: 02/07/2023] Open
Abstract
The fruit fly, Drosophila melanogaster, is preferentially found on fermenting fruits. The yeasts that dominate the microbial communities of these substrates are the primary food source for developing D. melanogaster larvae, and adult flies manifest a strong olfactory system-mediated attraction for the volatile compounds produced by these yeasts during fermentation. Although most work on this interaction has focused on the standard laboratory yeast Saccharomyces cerevisiae, a wide variety of other yeasts naturally ferment fallen fruit. Here we address the open question of whether D. melanogaster preferentially associates with distinct yeasts in different, closely-related environments. We characterized the spatial and temporal dynamics of Drosophila-associated fungi in Northern California wineries that use organic grapes and natural fermentation using high-throughput, short-amplicon sequencing. We found that there is nonrandom structure in the fungal communities that are vectored by flies both between and within vineyards. Within wineries, the fungal communities associated with flies in cellars, fermentation tanks, and pomace piles are distinguished by varying abundances of a small number of yeast species. To investigate the origins of this structure, we assayed Drosophila attraction to, oviposition on, larval development in, and longevity when consuming the yeasts that distinguish vineyard microhabitats from each other. We found that wild fly lines did not respond differentially to the yeast species that distinguish winery habitats in habitat specific manner. Instead, this subset of yeast shares traits that make them attractive to and ensure their close association with Drosophila.
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Affiliation(s)
- Allison S. Quan
- Department of Molecular and Cell Biology, University of California, Berkeley, California, United States of America
| | - Michael B. Eisen
- Department of Molecular and Cell Biology, University of California, Berkeley, California, United States of America
- Department of Integrative Biology, University of California, Berkeley, California, United States of America
- Howard Hughes Medical Institute, University of California, Berkeley, California, United States of America
- * E-mail:
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Ryvkin J, Bentzur A, Zer-Krispil S, Shohat-Ophir G. Mechanisms Underlying the Risk to Develop Drug Addiction, Insights From Studies in Drosophila melanogaster. Front Physiol 2018; 9:327. [PMID: 29740329 PMCID: PMC5928757 DOI: 10.3389/fphys.2018.00327] [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: 12/30/2017] [Accepted: 03/15/2018] [Indexed: 12/21/2022] Open
Abstract
The ability to adapt to environmental changes is an essential feature of biological systems, achieved in animals by a coordinated crosstalk between neuronal and hormonal programs that allow rapid and integrated organismal responses. Reward systems play a key role in mediating this adaptation by reinforcing behaviors that enhance immediate survival, such as eating or drinking, or those that ensure long-term survival, such as sexual behavior or caring for offspring. Drugs of abuse co-opt neuronal and molecular pathways that mediate natural rewards, which under certain circumstances can lead to addiction. Many factors can contribute to the transition from drug use to drug addiction, highlighting the need to discover mechanisms underlying the progression from initial drug use to drug addiction. Since similar responses to natural and drug rewards are present in very different animals, it is likely that the central systems that process reward stimuli originated early in evolution, and that common ancient biological principles and genes are involved in these processes. Thus, the neurobiology of natural and drug rewards can be studied using simpler model organisms that have their systems stripped of some of the immense complexity that exists in mammalian brains. In this paper we review studies in Drosophila melanogaster that model different aspects of natural and drug rewards, with an emphasis on how motivational states shape the value of the rewarding experience, as an entry point to understanding the mechanisms that contribute to the vulnerability of drug addiction.
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Affiliation(s)
- Julia Ryvkin
- The Mina & Everard Goodman Faculty of Life Sciences and The Leslie and Susan Gonda Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat Gan, Israel
| | - Assa Bentzur
- The Mina & Everard Goodman Faculty of Life Sciences and The Leslie and Susan Gonda Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat Gan, Israel
| | - Shir Zer-Krispil
- The Mina & Everard Goodman Faculty of Life Sciences and The Leslie and Susan Gonda Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat Gan, Israel
| | - Galit Shohat-Ophir
- The Mina & Everard Goodman Faculty of Life Sciences and The Leslie and Susan Gonda Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat Gan, Israel
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Evolutionary compromises to metabolic toxins: Ammonia and urea tolerance in Drosophila suzukii and Drosophila melanogaster. Physiol Behav 2018; 191:146-154. [PMID: 29679661 DOI: 10.1016/j.physbeh.2018.04.021] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2017] [Revised: 04/06/2018] [Accepted: 04/15/2018] [Indexed: 01/19/2023]
Abstract
The invasive pest Drosophila suzukii has evolved morphological and behavioural adaptations to lay eggs under the skin of fresh fruits. This results in severe damage to a wide range of small fruits. Drosophila suzukii females typically lay few eggs per fruit, preferring healthy fruits. Hence, larvae are exposed to a reduced amount of nitrogenous waste. Differently, the innocuous Drosophila melanogaster lays eggs on fermented fruits already infested by conspecifics, with larvae developing in a crowded environment with the accumulation of nitrogenous waste such as ammonia and urea. These compounds derive from nitrogen metabolism, protein degradation, and amino acids catabolism and are relatively toxic at high concentrations in an organism. The observed differences in oviposition site and larval ecological niche suggest that these species might differ in behavioural and physiological mechanisms used to cope with nitrogenous waste. We investigated how different concentrations of ammonia and urea affect oviposition and larval development in both species. Females and larvae of D. suzukii showed greater susceptibility to high concentrations of both compounds, with a dramatic decrease in the number of eggs laid and egg viability. Moreover, we tested the chemotactic response of third instar larvae to high concentrations of the compounds. Interestingly, ammonia resulted in a repulsive behaviour in respect of the control and urea groups. To better understand the pathways underlying these differences, we evaluated the effect on ornithine aminotransferase and glutathione-S-transferase, two enzymes involved in nitrogen metabolism and stress response that are expressed during larval development. Both ammonia and urea significantly reduced the expression of these enzymes in D. suzukii compared to D. melanogaster. This shows how the ecological shift of D. suzukii to fresh fruit is accompanied by less efficient detoxifying and excretory mechanisms, with important implications for evolutionary biology and applied research. Our data suggest that the ecological shift of D. suzukii to fresh fruit as oviposition substrate is accompanied by a reduced tolerance to metabolic toxins during larval development.
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Lowenstein EG, Velazquez-Ulloa NA. A Fly's Eye View of Natural and Drug Reward. Front Physiol 2018; 9:407. [PMID: 29720947 PMCID: PMC5915475 DOI: 10.3389/fphys.2018.00407] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Accepted: 04/04/2018] [Indexed: 12/18/2022] Open
Abstract
Animals encounter multiple stimuli each day. Some of these stimuli are innately appetitive or aversive, while others are assigned valence based on experience. Drugs like ethanol can elicit aversion in the short term and attraction in the long term. The reward system encodes the predictive value for different stimuli, mediating anticipation for attractive or punishing stimuli and driving animal behavior to approach or avoid conditioned stimuli. The neurochemistry and neurocircuitry of the reward system is partly evolutionarily conserved. In both vertebrates and invertebrates, including Drosophila melanogaster, dopamine is at the center of a network of neurotransmitters and neuromodulators acting in concert to encode rewards. Behavioral assays in D. melanogaster have become increasingly sophisticated, allowing more direct comparison with mammalian research. Moreover, recent evidence has established the functional modularity of the reward neural circuits in Drosophila. This functional modularity resembles the organization of reward circuits in mammals. The powerful genetic and molecular tools for D. melanogaster allow characterization and manipulation at the single-cell level. These tools are being used to construct a detailed map of the neural circuits mediating specific rewarding stimuli and have allowed for the identification of multiple genes and molecular pathways that mediate the effects of reinforcing stimuli, including their rewarding effects. This report provides an overview of the research on natural and drug reward in D. melanogaster, including natural rewards such as sugar and other food nutrients, and drug rewards including ethanol, cocaine, amphetamine, methamphetamine, and nicotine. We focused mainly on the known genetic and neural mechanisms underlying appetitive reward for sugar and reward for ethanol. We also include genes, molecular pathways, and neural circuits that have been identified using assays that test the palatability of the rewarding stimulus, the preference for the rewarding stimulus, or other effects of the stimulus that indicate how it can modify behavior. Commonalities between mechanisms of natural and drug reward are highlighted and future directions are presented, putting forward questions best suited for research using D. melanogaster as a model organism.
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Affiliation(s)
- Eve G Lowenstein
- Department of Biology, Lewis & Clark College, Portland, OR, United States
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Potdar S, Daniel DK, Thomas FA, Lall S, Sheeba V. Sleep deprivation negatively impacts reproductive output in Drosophila melanogaster. ACTA ACUST UNITED AC 2018; 221:jeb.174771. [PMID: 29361608 DOI: 10.1242/jeb.174771] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Accepted: 12/21/2017] [Indexed: 12/11/2022]
Abstract
Most animals sleep or exhibit a sleep-like state, yet the adaptive significance of this phenomenon remains unclear. Although reproductive deficits are associated with lifestyle-induced sleep deficiencies, how sleep loss affects reproductive physiology is poorly understood, even in model organisms. We aimed to bridge this mechanistic gap by impairing sleep in female fruit flies and testing its effect on egg output. We found that sleep deprivation by feeding caffeine or by mechanical perturbation resulted in decreased egg output. Transient activation of wake-promoting dopaminergic neurons decreased egg output in addition to sleep levels, thus demonstrating a direct negative impact of sleep deficit on reproductive output. Similarly, loss-of-function mutation in dopamine transporter fumin (fmn) led to both significant sleep loss and lowered fecundity. This demonstration of a direct relationship between sleep and reproductive fitness indicates a strong driving force for the evolution of sleep.
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Affiliation(s)
- Sheetal Potdar
- Behavioural Neurogenetics Laboratory, Evolutionary and Integrative Biology Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore 560064, India
| | - Danita K Daniel
- Behavioural Neurogenetics Laboratory, Evolutionary and Integrative Biology Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore 560064, India
| | - Femi A Thomas
- Behavioural Neurogenetics Laboratory, Evolutionary and Integrative Biology Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore 560064, India
| | - Shraddha Lall
- Neuroscience Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore 560064, India
| | - Vasu Sheeba
- Behavioural Neurogenetics Laboratory, Evolutionary and Integrative Biology Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore 560064, India .,Neuroscience Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore 560064, India
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Koyyada R, Latchooman N, Jonaitis J, Ayoub SS, Corcoran O, Casalotti SO. Naltrexone Reverses Ethanol Preference and Protein Kinase C Activation in Drosophila melanogaster. Front Physiol 2018; 9:175. [PMID: 29593550 PMCID: PMC5861182 DOI: 10.3389/fphys.2018.00175] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Accepted: 02/20/2018] [Indexed: 12/13/2022] Open
Abstract
Alcohol use disorder (AUD) is a major health, social and economic problem for which there are few effective treatments. The opiate antagonist naltrexone is currently prescribed clinically with mixed success. We have used naltrexone in an established behavioral assay (CAFE) in Drosophila melanogaster that measures the flies' preference for ethanol-containing food. We have confirmed that Drosophila exposed to ethanol develop a preference toward this drug and we demonstrate that naltrexone, in a dose dependant manner, reverses the ethanol-induced ethanol preference. This effect is not permanent, as preference for alcohol returns after discontinuing naltrexone. Additionally, naltrexone reduced the alcohol-induced increase in protein kinase C activity. These findings are of interest because they confirm that Drosophila is a useful model for studying human responses to addictive drugs. Additionally because of the lack of a closely conserved opiate system in insects, our results could either indicate that a functionally related system does exist in insects or that in insects, and potentially also in mammals, naltrexone binds to alternative sites. Identifying such sites could lead to improved treatment strategies for AUD.
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Affiliation(s)
- Rajeswari Koyyada
- Medicines Research Group, School of Health, Sport and Bioscience, University of East London, London, United Kingdom
| | - Nilesh Latchooman
- Medicines Research Group, School of Health, Sport and Bioscience, University of East London, London, United Kingdom
| | - Julius Jonaitis
- Medicines Research Group, School of Health, Sport and Bioscience, University of East London, London, United Kingdom
| | - Samir S Ayoub
- Medicines Research Group, School of Health, Sport and Bioscience, University of East London, London, United Kingdom
| | - Olivia Corcoran
- Medicines Research Group, School of Health, Sport and Bioscience, University of East London, London, United Kingdom
| | - Stefano O Casalotti
- Medicines Research Group, School of Health, Sport and Bioscience, University of East London, London, United Kingdom
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Dewar ADM, Wystrach A, Philippides A, Graham P. Neural coding in the visual system of Drosophila melanogaster: How do small neural populations support visually guided behaviours? PLoS Comput Biol 2017; 13:e1005735. [PMID: 29016606 PMCID: PMC5654266 DOI: 10.1371/journal.pcbi.1005735] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Revised: 10/20/2017] [Accepted: 08/21/2017] [Indexed: 01/23/2023] Open
Abstract
All organisms wishing to survive and reproduce must be able to respond adaptively to a complex, changing world. Yet the computational power available is constrained by biology and evolution, favouring mechanisms that are parsimonious yet robust. Here we investigate the information carried in small populations of visually responsive neurons in Drosophila melanogaster. These so-called 'ring neurons', projecting to the ellipsoid body of the central complex, are reported to be necessary for complex visual tasks such as pattern recognition and visual navigation. Recently the receptive fields of these neurons have been mapped, allowing us to investigate how well they can support such behaviours. For instance, in a simulation of classic pattern discrimination experiments, we show that the pattern of output from the ring neurons matches observed fly behaviour. However, performance of the neurons (as with flies) is not perfect and can be easily improved with the addition of extra neurons, suggesting the neurons' receptive fields are not optimised for recognising abstract shapes, a conclusion which casts doubt on cognitive explanations of fly behaviour in pattern recognition assays. Using artificial neural networks, we then assess how easy it is to decode more general information about stimulus shape from the ring neuron population codes. We show that these neurons are well suited for encoding information about size, position and orientation, which are more relevant behavioural parameters for a fly than abstract pattern properties. This leads us to suggest that in order to understand the properties of neural systems, one must consider how perceptual circuits put information at the service of behaviour.
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Affiliation(s)
- Alex D. M. Dewar
- Department of Informatics, University of Sussex, Falmer, Brighton, United Kingdom
| | - Antoine Wystrach
- Centre de Recherches sur la Cognition Animale, Centre National de la Recherche Scientifique, Université Paul Sabatier, Toulouse, France
| | - Andrew Philippides
- Department of Informatics, University of Sussex, Falmer, Brighton, United Kingdom
| | - Paul Graham
- School of Life Sciences, University of Sussex, Falmer, Brighton, United Kingdom
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Giang T, He J, Belaidi S, Scholz H. Key Odorants Regulate Food Attraction in Drosophila melanogaster. Front Behav Neurosci 2017; 11:160. [PMID: 28928642 PMCID: PMC5591870 DOI: 10.3389/fnbeh.2017.00160] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Accepted: 08/15/2017] [Indexed: 11/13/2022] Open
Abstract
In insects, the search for food is highly dependent on olfactory sensory input. Here, we investigated whether a single key odorant within an odor blend or the complexity of the odor blend influences the attraction of Drosophila melanogaster to a food source. A key odorant is defined as an odorant that elicits a difference in the behavioral response when two similar complex odor blends are offered. To validate that the observed behavioral responses were elicited by olfactory stimuli, we used olfactory co-receptor Orco mutants. We show that within a food odor blend, ethanol functions as a key odorant. In addition to ethanol other odorants might serve as key odorants at specific concentrations. However, not all odorants are key odorants. The intensity of the odor background influences the attractiveness of the key odorants. Increased complexity is only more attractive in a concentration-dependent range for single compounds in a blend. Orco is necessary to discriminate between two similarly attractive odorants when offered as single odorants and in food odor blends, supporting the importance of single odorant recognition in odor blends. These data strongly indicate that flies use more than one strategy to navigate to a food odor source, depending on the availability of key odorants in the odor blend and the alternative odor offered.
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Affiliation(s)
- Thomas Giang
- Department of Biology, Albertus-Magnus University of CologneCologne, Germany
| | - Jianzheng He
- Department of Biology, Albertus-Magnus University of CologneCologne, Germany
| | - Safaa Belaidi
- Department of Biology, Albertus-Magnus University of CologneCologne, Germany
| | - Henrike Scholz
- Department of Biology, Albertus-Magnus University of CologneCologne, Germany
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