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Kim AT, Li S, Kim Y, You YJ, Park Y. Food preference-based screening method for identification of effectors of substance use disorders using Caenorhabditis elegans. Life Sci 2024; 345:122580. [PMID: 38514005 DOI: 10.1016/j.lfs.2024.122580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 02/26/2024] [Accepted: 03/18/2024] [Indexed: 03/23/2024]
Abstract
Substance use disorder (SUD) affects over 48 million Americans aged 12 and over. Thus, identifying novel chemicals contributing to SUD will be critical for developing efficient prevention and mitigation strategies. Considering the complexity of the actions and effects of these substances on human behavior, a high-throughput platform using a living organism is ideal. We developed a quick and easy screening assay using Caenorhabditis elegans. C. elegans prefers high-quality food (Escherichia coli HB101) over low-quality food (Bacillus megaterium), with a food preference index of approximately 0.2, defined as the difference in the number of worms at E. coli HB101 and B. megaterium over the total worm number. The food preference index was significantly increased by loperamide, a μ-opioid receptor (MOPR) agonist, and decreased by naloxone, a MOPR antagonist. These changes depended on npr-17, a C. elegans homolog of opioid receptors. In addition, the food preference index was significantly increased by arachidonyl-2'-chloroethylamide, a cannabinoid 1 receptor (CB1R) agonist, and decreased by rimonabant, a CB1R inverse agonist. These changes depended on npr-19, a homolog of CB1R. These results suggest that the conserved opioid and endocannabinoid systems modulate the food preference behaviors of C. elegans. Finally, the humanoid C. elegans strains where npr-17 was replaced with human MOPR and where npr-19 was replaced with human CB1R phenocopied the changes in food preference by the drug treatment. Together, the current results show that this method can be used to rapidly screen the potential effectors of MOPR and CB1R to yield results highly translatable to humans.
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Affiliation(s)
- Aaron Taehwan Kim
- Department of Food Science, University of Massachusetts, Amherst, MA 01003, USA
| | - Sida Li
- Department of Food Science, University of Massachusetts, Amherst, MA 01003, USA
| | - Yoo Kim
- Department of Nutritional Sciences, Oklahoma State University, Stillwater, OK 74078, USA
| | - Young-Jai You
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Yeonhwa Park
- Department of Food Science, University of Massachusetts, Amherst, MA 01003, USA.
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2
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Li R, Xu Y, Wen X, Chen YH, Wang PZ, Zhao JL, Wu PP, Wu JJ, Liu H, Huang JH, Li SJ, Wu ZX. GCY-20 signaling controls suppression of Caenorhabditis elegans egg laying by moderate cold. Cell Rep 2024; 43:113708. [PMID: 38294902 DOI: 10.1016/j.celrep.2024.113708] [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: 06/09/2023] [Revised: 10/19/2023] [Accepted: 01/11/2024] [Indexed: 02/02/2024] Open
Abstract
Organisms sensing environmental cues and internal states and integrating the sensory information to control fecundity are essential for survival and proliferation. The present study finds that a moderate cold temperature of 11°C reduces egg laying in Caenorhabditis elegans. ASEL and AWC neurons sense the cold via GCY-20 signaling and act antagonistically on egg laying through the ASEL and AWC/AIA/HSN circuits. Upon cold stimulation, ASEL and AWC release glutamate to activate and inhibit AIA interneurons by acting on highly and lowly sensitive ionotropic GLR-2 and GLC-3 receptors, respectively. AIA inhibits HSN motor neuron activity via acetylcholinergic ACR-14 receptor signaling and suppresses egg laying. Thus, ASEL and AWC initiate and reduce the cold suppression of egg laying. ASEL's action on AIA and egg laying dominates AWC's action. The biased opposite actions of these neurons on egg laying provide animals with a precise adaptation of reproductive behavior to environmental temperatures.
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Affiliation(s)
- Rong Li
- Key Laboratory of Molecular Biophysics of Ministry of Education, Institute of Biophysics and Biochemistry, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
| | - Yu Xu
- Key Laboratory of Molecular Biophysics of Ministry of Education, Institute of Biophysics and Biochemistry, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
| | - Xin Wen
- College of Life Science, Henan Agricultural University, Zhengzhou, Henan, China
| | - Yuan-Hua Chen
- Key Laboratory of Molecular Biophysics of Ministry of Education, Institute of Biophysics and Biochemistry, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
| | - Ping-Zhou Wang
- Key Laboratory of Molecular Biophysics of Ministry of Education, Institute of Biophysics and Biochemistry, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
| | - Jia-Lu Zhao
- Key Laboratory of Molecular Biophysics of Ministry of Education, Institute of Biophysics and Biochemistry, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
| | - Piao-Ping Wu
- Key Laboratory of Molecular Biophysics of Ministry of Education, Institute of Biophysics and Biochemistry, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
| | - Jing-Jing Wu
- Key Laboratory of Molecular Biophysics of Ministry of Education, Institute of Biophysics and Biochemistry, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
| | - Hui Liu
- Key Laboratory of Molecular Biophysics of Ministry of Education, Institute of Biophysics and Biochemistry, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
| | - Jia-Hao Huang
- Key Laboratory of Molecular Biophysics of Ministry of Education, Institute of Biophysics and Biochemistry, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
| | - Si-Jia Li
- Key Laboratory of Molecular Biophysics of Ministry of Education, Institute of Biophysics and Biochemistry, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
| | - Zheng-Xing Wu
- Key Laboratory of Molecular Biophysics of Ministry of Education, Institute of Biophysics and Biochemistry, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China.
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3
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Salim C, Batsaikhan E, Kan AK, Chen H, Jee C. Nicotine Motivated Behavior in C. elegans. Int J Mol Sci 2024; 25:1634. [PMID: 38338915 PMCID: PMC10855306 DOI: 10.3390/ijms25031634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Revised: 01/20/2024] [Accepted: 01/22/2024] [Indexed: 02/12/2024] Open
Abstract
To maximize the advantages offered by Caenorhabditis elegans as a high-throughput (HTP) model for nicotine dependence studies, utilizing its well-defined neuroconnectome as a robust platform, and to unravel the genetic basis of nicotine-motivated behaviors, we established the nicotine conditioned cue preference (CCP) paradigm. Nicotine CCP enables the assessment of nicotine preference and seeking, revealing a parallel to fundamental aspects of nicotine-dependent behaviors observed in mammals. We demonstrated that nicotine-elicited cue preference in worms is mediated by nicotinic acetylcholine receptors and requires dopamine for CCP development. Subsequently, we pinpointed nAChR subunits associated with nicotine preference and validated human GWAS candidates linked to nicotine dependence involved in nAChRs. Functional validation involves assessing the loss-of-function strain of the CACNA2D3 ortholog and the knock-out (KO) strain of the CACNA2D2 ortholog, closely related to CACNA2D3 and sharing human smoking phenotypes. Our orthogonal approach substantiates the functional conservation of the α2δ subunit of the calcium channel in nicotine-motivated behavior. Nicotine CCP in C. elegans serves as a potent affirmation of the cross-species functional relevance of GWAS candidate genes involved in nicotine seeking associated with tobacco abuse, providing a streamlined yet comprehensive system for investigating intricate behavioral paradigms within a simplified and reliable framework.
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Affiliation(s)
| | | | | | | | - Changhoon Jee
- Department of Pharmacology, Addiction Science and Toxicology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN 38163, USA; (C.S.)
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4
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McMillen A, Chew Y. Neural mechanisms of dopamine function in learning and memory in Caenorhabditis elegans. Neuronal Signal 2024; 8:NS20230057. [PMID: 38572143 PMCID: PMC10987485 DOI: 10.1042/ns20230057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Revised: 12/03/2023] [Accepted: 12/11/2023] [Indexed: 04/05/2024] Open
Abstract
Research into learning and memory over the past decades has revealed key neurotransmitters that regulate these processes, many of which are evolutionarily conserved across diverse species. The monoamine neurotransmitter dopamine is one example of this, with countless studies demonstrating its importance in regulating behavioural plasticity. However, dopaminergic neural networks in the mammalian brain consist of hundreds or thousands of neurons, and thus cannot be studied at the level of single neurons acting within defined neural circuits. The nematode Caenorhabditis elegans (C. elegans) has an experimentally tractable nervous system with a completely characterized synaptic connectome. This makes it an advantageous system to undertake mechanistic studies into how dopamine encodes lasting yet flexible behavioural plasticity in the nervous system. In this review, we synthesize the research to date exploring the importance of dopaminergic signalling in learning, memory formation, and forgetting, focusing on research in C. elegans. We also explore the potential for dopamine-specific fluorescent biosensors in C. elegans to visualize dopaminergic neural circuits during learning and memory formation in real-time. We propose that the use of these sensors in C. elegans, in combination with optogenetic and other light-based approaches, will further illuminate the detailed spatiotemporal requirements for encoding behavioural plasticity in an accessible experimental system. Understanding the key molecules and circuit mechanisms that regulate learning and forgetting in more compact invertebrate nervous systems may reveal new druggable targets for enhancing memory storage and delaying memory loss in bigger brains.
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Affiliation(s)
- Anna McMillen
- College of Medicine and Public Health and Flinders Health and Medical Research Institute, Flinders University, Bedford Park, 5042, South Australia, Australia
| | - Yee Lian Chew
- College of Medicine and Public Health and Flinders Health and Medical Research Institute, Flinders University, Bedford Park, 5042, South Australia, Australia
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5
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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: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [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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6
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Albrecht PA, Fernandez-Hubeid LE, Deza-Ponzio R, Martins AC, Aschner M, Virgolini MB. Developmental lead exposure affects dopaminergic neuron morphology and modifies basal slowing response in Caenorhabditis elegans: effects of ethanol. Neurotoxicology 2022; 91:349-359. [PMID: 35724878 DOI: 10.1016/j.neuro.2022.06.005] [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: 03/30/2022] [Revised: 06/04/2022] [Accepted: 06/13/2022] [Indexed: 11/28/2022]
Abstract
Lead (Pb) and ethanol (EtOH) are neurotoxicants that affect the dopaminergic (DAergic) system. We first sought to assess the morphology of the DAergic neurons in the Caenorhabditis elegans BY200 strain. The results demonstrated dose-dependent damage in these neurons induced by developmental Pb exposure. Secondly, transgenic worms exposed to 24μM Pb and administered with 200mM EtOH were evaluated in the basal slowing response (BSR). Pb induced impairment in the BSR in the wild-type strain that did not improve in response to EtOH, an effect also observed in strains that lack the DOP-1, DOP-2, and DOP-3 receptors. The animals that overexpress tyrosine hydroxylase (TH), or lack the vesicular transport (VMAT) showed a Pb-induced impairment in the BSR that seemed to improve after EtOH. Interestingly, a dramatic impairment in the BSR was observed in the Pb group in strains lacking the DOP-4 receptor, resembling the response of the TH-deficient strain, an effect that in both cases showed a non-significant reversal by EtOH. These results suggest that the facilitatory effect of EtOH on the impaired BSR observed in Pb-exposed null mutant strains may be the result of a compensatory effect in the altered DAergic synapse present in these animals.
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Affiliation(s)
- Paula A Albrecht
- Instituto de Farmacología Experimental de Córdoba-Consejo Nacional de Investigaciones Técnicas (IFEC-CONICET) and Departamento de Farmacología Otto Orsingher, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, X5000HUA, Córdoba, Argentina
| | - Lucia E Fernandez-Hubeid
- Instituto de Farmacología Experimental de Córdoba-Consejo Nacional de Investigaciones Técnicas (IFEC-CONICET) and Departamento de Farmacología Otto Orsingher, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, X5000HUA, Córdoba, Argentina
| | - Romina Deza-Ponzio
- Instituto de Farmacología Experimental de Córdoba-Consejo Nacional de Investigaciones Técnicas (IFEC-CONICET) and Departamento de Farmacología Otto Orsingher, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, X5000HUA, Córdoba, Argentina
| | - Airton C Martins
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Miriam B Virgolini
- Instituto de Farmacología Experimental de Córdoba-Consejo Nacional de Investigaciones Técnicas (IFEC-CONICET) and Departamento de Farmacología Otto Orsingher, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, X5000HUA, Córdoba, Argentina.
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7
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Jiang Y, Gaur U, Cao Z, Hou ST, Zheng W. Dopamine D1- and D2-like receptors oppositely regulate lifespan via a dietary restriction mechanism in Caenorhabditis elegans. BMC Biol 2022; 20:71. [PMID: 35317792 PMCID: PMC8941781 DOI: 10.1186/s12915-022-01272-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Accepted: 03/04/2022] [Indexed: 01/02/2023] Open
Abstract
BACKGROUND Despite recent progress in understanding the molecular mechanisms regulating aging and lifespan, and the pathways involved being conserved in different species, a full understanding of the aging process has not been reached. In particular, increasing evidence suggests an active role for the nervous system in lifespan regulation, with sensory neurons, as well as serotonin and GABA signaling, having been shown to regulate lifespan in Caenorhabditis elegans (C. elegans). However, the contribution of additional neural factors, and a broad understanding of the role of the nervous system in regulating aging remains to be established. Here, we examine the impact of the dopamine system in regulating aging in C. elegans. RESULTS We report that mutations of DOP-4, a dopamine D1-like receptor (D1R), and DOP-2, a dopamine D2-like receptor (D2R) oppositely affected lifespan, fast body movement span, reproductive lifespan, and developmental rate in C. elegans. Activation of D2R using aripiprazole, an antipsychotic drug, robustly extended both lifespan and healthspan. Conversely, inhibition of D2R using quetiapine shortened worm lifespan, further supporting the role of dopamine receptors in lifespan regulation. Mechanistically, D2R signaling regulates lifespan through a dietary restriction mechanism mediated by the AAK-2-DAF-16 pathway. The DAG-PKC/PKD pathway links signaling between dopamine receptors and the downstream AAK-2-DAF-16 pathway to transmit longevity signals. CONCLUSIONS These data demonstrated a novel role of dopamine receptors in lifespan and dietary restriction regulation. The clinically approved antipsychotic aripiprazole holds potential as a novel anti-aging drug.
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Affiliation(s)
- Yizhou Jiang
- Centre of Reproduction, Development & Aging and Institute of Translation Medicine, Faculty of Health Sciences, University of Macau, Avenida de Universidade, Taipa, Macau, China.,Brain Research Centre and Department of Biology, Southern University of Science and Technology, 1088 Xueyuan Blvd, Nanshan District, Shenzhen, Guangdong Province, China
| | - Uma Gaur
- Centre of Reproduction, Development & Aging and Institute of Translation Medicine, Faculty of Health Sciences, University of Macau, Avenida de Universidade, Taipa, Macau, China
| | - Zhibai Cao
- Centre of Reproduction, Development & Aging and Institute of Translation Medicine, Faculty of Health Sciences, University of Macau, Avenida de Universidade, Taipa, Macau, China
| | - Sheng-Tao Hou
- Brain Research Centre and Department of Biology, Southern University of Science and Technology, 1088 Xueyuan Blvd, Nanshan District, Shenzhen, Guangdong Province, China.
| | - Wenhua Zheng
- Centre of Reproduction, Development & Aging and Institute of Translation Medicine, Faculty of Health Sciences, University of Macau, Avenida de Universidade, Taipa, Macau, China.
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Transcriptome Analysis of the Marine Nematode Litoditis marina in a Chemically Defined Food Environment with Stearic Acid Supplementation. JOURNAL OF MARINE SCIENCE AND ENGINEERING 2022. [DOI: 10.3390/jmse10030428] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Stearic acid represents one of the most abundant fatty acids in the Western diet and profoundly regulates health and diseases of animals and human beings. We previously showed that stearic acid supplementation promoted development of the terrestrial model nematode Caenorhabditis elegans in chemically defined CeMM food environment. However, whether stearic acid regulates development of other nematodes remains unknown. Here, we found that dietary supplementation with stearic acid could promote the development of the marine nematode Litoditis marina, belonging to the same family as C. elegans, indicating the conserved roles of stearic acid in developmental regulation. We further employed transcriptome analysis to analyze genome-wide transcriptional signatures of L. marina with dietary stearic acid supplementation. We found that stearic acid might promote development of L. marina via upregulation of the expression of genes involved in aminoacyl-tRNA biosynthesis, translation initiation and elongation, ribosome biogenesis, and transmembrane transport. In addition, we observed that the expression of neuronal signaling-related genes was decreased. This study provided important insights into how a single fatty acid stearic acid regulates development of marine nematode, and further studies with CRISPR genome editing will facilitate demonstrating the molecular mechanisms underlying how a single metabolite regulates animal development and health.
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Chou SH, Chen YJ, Liao CP, Pan CL. A role for dopamine in C. elegans avoidance behavior induced by mitochondrial stress. Neurosci Res 2022; 178:87-92. [PMID: 35074444 DOI: 10.1016/j.neures.2022.01.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 12/21/2021] [Accepted: 01/17/2022] [Indexed: 01/11/2023]
Abstract
Physiological stress triggers aversive learning that profoundly alters animal behavior. Systemic mitochondrial disruption induces avoidance of C. elegans to non-pathogenic food bacteria. Mutations in cat-2 and dat-1, which control dopamine synthesis and reuptake, respectively, impair this learned bacterial avoidance, suggesting that dopaminergic modulation is essential. Cell-specific rescue experiments indicate that dopamine likely acts from the CEP and ADE neurons to regulate learned bacterial avoidance. We find that mutations in multiple dopamine receptor genes, including dop-1, dop-2 and dop-3, reduced learned bacterial avoidance. Our work reveals a role for dopamine signaling in C. elegans learned avoidance behavior induced by mitochondrial stress.
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Affiliation(s)
- Shih-Hua Chou
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei 10002, Taiwan; Center of Precision Medicine, College of Medicine, National Taiwan University, Taipei 10002, Taiwan
| | - Yen-Ju Chen
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei 10002, Taiwan; Center of Precision Medicine, College of Medicine, National Taiwan University, Taipei 10002, Taiwan
| | - Chien-Po Liao
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei 10002, Taiwan
| | - Chun-Liang Pan
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei 10002, Taiwan; Center of Precision Medicine, College of Medicine, National Taiwan University, Taipei 10002, Taiwan.
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10
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Otarigho B, Aballay A. Immunity-longevity tradeoff neurally controlled by GABAergic transcription factor PITX1/UNC-30. Cell Rep 2021; 35:109187. [PMID: 34038721 PMCID: PMC8227953 DOI: 10.1016/j.celrep.2021.109187] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 03/01/2021] [Accepted: 05/06/2021] [Indexed: 12/15/2022] Open
Abstract
A body of evidence indicates that metazoan immune and aging pathways are largely interconnected, but the mechanisms involved in their homeostatic control remain unclear. In this study, we find that the PITX (paired-like homeodomain) transcription factor UNC-30 controls the tradeoff between immunity and longevity from the nervous system in Caenorhabditis elegans. PITX/UNC-30 functional loss enhances immunity in a GATA/ELT-2- and p38 MAPK/PMK-1-dependent manner and reduced longevity by activating MXD/MDL-1 and the C2H2-type zinc finger transcription factor PQM-1. The immune inhibitory and longevity stimulatory functions of PITX/UNC-30 require the sensory neuron ASG and a signaling pathway controlled by NPR-1, which is a G protein-coupled receptor related to mammalian neuropeptide Y receptors. Our findings uncover a suppressive role of GABAergic signaling in the neural control of a biological tradeoff where energy is allocated toward immunity at the expense of longevity.
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Affiliation(s)
- Benson Otarigho
- Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, OR 97239, USA
| | - Alejandro Aballay
- Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, OR 97239, USA.
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11
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Xu Y, Zhang L, Liu Y, Topalidou I, Hassinan C, Ailion M, Zhao Z, Wang T, Chen Z, Bai J. Dopamine receptor DOP-1 engages a sleep pathway to modulate swimming in C. elegans. iScience 2021; 24:102247. [PMID: 33796839 PMCID: PMC7995527 DOI: 10.1016/j.isci.2021.102247] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 02/06/2021] [Accepted: 02/25/2021] [Indexed: 12/26/2022] Open
Abstract
Animals require robust yet flexible programs to support locomotion. Here we report a pathway that connects the D1-like dopamine receptor DOP-1 with a sleep mechanism to modulate swimming in C. elegans. We show that DOP-1 plays a negative role in sustaining swimming behavior. By contrast, a pathway through the D2-like dopamine receptor DOP-3 negatively regulates the initiation of swimming, but its impact fades quickly over a few minutes. We find that DOP-1 and the GPCR kinase (G-protein-coupled receptor kinase-2) function in the sleep interneuron RIS, where DOP-1 modulates the secretion of a sleep neuropeptide FLP-11. We further show that DOP-1 and FLP-11 act in the same pathway to modulate swimming. Together, these results delineate a functional connection between a dopamine receptor and a sleep program to regulate swimming in C. elegans. The temporal transition between DOP-3 and DOP-1 pathways highlights the dynamic nature of neuromodulation for rhythmic movements that persist over time.
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Affiliation(s)
- Ye Xu
- Department of Clinical Medicine, Nanjing Medical University, Nanjing 211166, P. R. China.,Basic Sciences Division, Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue N., Seattle, WA 98109, USA.,Department of Neurology, First Affiliated Hospital of Hainan Medical University, Hainan Medical University, Hainan 570102, P. R. China
| | - Lin Zhang
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue N., Seattle, WA 98109, USA
| | - Yan Liu
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue N., Seattle, WA 98109, USA
| | - Irini Topalidou
- Department of Biochemistry, University of Washington, WA 98195
| | - Cera Hassinan
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue N., Seattle, WA 98109, USA.,Molecular and Cellular Biology Program, University of Washington, Seattle, WA 98019
| | - Michael Ailion
- Department of Biochemistry, University of Washington, WA 98195
| | - Zhenqiang Zhao
- Department of Neurology, First Affiliated Hospital of Hainan Medical University, Hainan Medical University, Hainan 570102, P. R. China
| | - Tan Wang
- Department of Neurology, First Affiliated Hospital of Hainan Medical University, Hainan Medical University, Hainan 570102, P. R. China
| | - Zhibin Chen
- Department of Clinical Medicine, Nanjing Medical University, Nanjing 211166, P. R. China.,Department of Neurology, First Affiliated Hospital of Hainan Medical University, Hainan Medical University, Hainan 570102, P. R. China
| | - Jihong Bai
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue N., Seattle, WA 98109, USA.,Molecular and Cellular Biology Program, University of Washington, Seattle, WA 98019.,Department of Biochemistry, University of Washington, WA 98195
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12
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Suo S, Harada K, Matsuda S, Kyo K, Wang M, Maruyama K, Awaji T, Tsuboi T. Sexually Dimorphic Regulation of Behavioral States by Dopamine in Caenorhabditis elegans. J Neurosci 2019; 39:4668-4683. [PMID: 30988167 PMCID: PMC6561698 DOI: 10.1523/jneurosci.2985-18.2019] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2018] [Revised: 03/22/2019] [Accepted: 03/26/2019] [Indexed: 11/21/2022] Open
Abstract
Sex differences in behavior allow animals to effectively mate and reproduce. However, the mechanism by which biological sex regulates behavioral states, which underlie the regulation of sex-shared behaviors, such as locomotion, is largely unknown. In this study, we studied sex differences in the behavioral states of Caenorhabditis elegans and found that males spend less time in a low locomotor activity state than hermaphrodites and that dopamine generates this sex difference. In males, dopamine reduces the low activity state by acting in the same pathway as polycystic kidney disease-related genes that function in male-specific neurons. In hermaphrodites, dopamine increases the low activity state by suppression of octopamine signaling in the sex-shared SIA neurons, which have reduced responsiveness to octopamine in males. Furthermore, dopamine promotes exploration both inside and outside of bacterial lawn (the food source) in males and suppresses it in hermaphrodites. These results demonstrate that sexually dimorphic signaling allows the same neuromodulator to promote adaptive behavior for each sex.SIGNIFICANCE STATEMENT The mechanisms that generate sex differences in sex-shared behaviors, including locomotion, are not well understood. We show that there are sex differences in the regulation of behavioral states in the model animal Caenorhabditis elegans Dopamine promotes the high locomotor activity state in males, which must search for mates to reproduce, and suppresses it in self-fertilizing hermaphrodites through distinct molecular mechanisms. This study demonstrates that sex-specific signaling generates sex differences in the regulation of behavioral states, which in turn modulates the locomotor activity to suit reproduction for each sex.
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Affiliation(s)
- Satoshi Suo
- Department of Pharmacology, Faculty of Medicine, Saitama Medical University, Saitama, 350-0495, Japan,
| | - Kazuki Harada
- Department of Life Sciences, Graduate School of Arts and Sciences, University of Tokyo, Tokyo, 153-8902, Japan
| | - Shogo Matsuda
- Department of Biological Sciences, Graduate School of Science, University of Tokyo, Tokyo, 113-0033, Japan, and
| | - Koki Kyo
- Department of Human Sciences, Obihiro University of Agriculture and Veterinary Medicine, Hokkaido, 080-8555, Japan
| | - Min Wang
- Department of Pharmacology, Faculty of Medicine, Saitama Medical University, Saitama, 350-0495, Japan
| | - Kei Maruyama
- Department of Pharmacology, Faculty of Medicine, Saitama Medical University, Saitama, 350-0495, Japan
| | - Takeo Awaji
- Department of Pharmacology, Faculty of Medicine, Saitama Medical University, Saitama, 350-0495, Japan
| | - Takashi Tsuboi
- Department of Life Sciences, Graduate School of Arts and Sciences, University of Tokyo, Tokyo, 153-8902, Japan
- Department of Biological Sciences, Graduate School of Science, University of Tokyo, Tokyo, 113-0033, Japan, and
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13
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Koelle MR. Neurotransmitter signaling through heterotrimeric G proteins: insights from studies in C. elegans. WORMBOOK : THE ONLINE REVIEW OF C. ELEGANS BIOLOGY 2018; 2018:1-52. [PMID: 26937633 PMCID: PMC5010795 DOI: 10.1895/wormbook.1.75.2] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Neurotransmitters signal via G protein coupled receptors (GPCRs) to modulate activity of neurons and muscles. C. elegans has ∼150 G protein coupled neuropeptide receptor homologs and 28 additional GPCRs for small-molecule neurotransmitters. Genetic studies in C. elegans demonstrate that neurotransmitters diffuse far from their release sites to activate GPCRs on distant cells. Individual receptor types are expressed on limited numbers of cells and thus can provide very specific regulation of an individual neural circuit and behavior. G protein coupled neurotransmitter receptors signal principally via the three types of heterotrimeric G proteins defined by the G alpha subunits Gαo, Gαq, and Gαs. Each of these G alpha proteins is found in all neurons plus some muscles. Gαo and Gαq signaling inhibit and activate neurotransmitter release, respectively. Gαs signaling, like Gαq signaling, promotes neurotransmitter release. Many details of the signaling mechanisms downstream of Gαq and Gαs have been delineated and are consistent with those of their mammalian orthologs. The details of the signaling mechanism downstream of Gαo remain a mystery. Forward genetic screens in C. elegans have identified new molecular components of neural G protein signaling mechanisms, including Regulators of G protein Signaling (RGS proteins) that inhibit signaling, a new Gαq effector (the Trio RhoGEF domain), and the RIC-8 protein that is required for neuronal Gα signaling. A model is presented in which G proteins sum up the variety of neuromodulator signals that impinge on a neuron to calculate its appropriate output level.
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Affiliation(s)
- Michael R Koelle
- Department of Molecular Biophysics & Biochemistry, Yale University, New Haven CT 06520 USA
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14
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Osuna-Luque J, Rodríguez-Ramos Á, Gámez-Del-Estal MDM, Ruiz-Rubio M. Behavioral Mechanisms That Depend on Dopamine and Serotonin in Caenorhabditis elegans Interact With the Antipsychotics Risperidone and Aripiprazole. J Exp Neurosci 2018; 12:1179069518798628. [PMID: 30245571 PMCID: PMC6144587 DOI: 10.1177/1179069518798628] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Accepted: 08/14/2018] [Indexed: 11/20/2022] Open
Abstract
The neurotransmitters dopamine and serotonin participate in specific behavioral neuromuscular mechanisms in the nematode Caenorhabditis elegans. Dopamine is involved in the gentle touch response and serotonin in the pharyngeal pumping rate. In its genome, the worm presents genes encoding dopamine and serotonin receptors orthologous to those of human genes. Risperidone and aripiprazole are a class of drugs known as atypical antipsychotics commonly used to treat schizophrenia, bipolar disorder, and irritability associated with autism. Risperidone is an antagonist of the dopamine D2 and serotonin 5-HT2A receptors. Aripiprazole functions as a partial agonist of the dopamine D2 receptor and as a partial agonist and antagonist of 5-HT1A and 5-HT2A serotonin receptors, respectively. Our results show that risperidone and aripiprazole alter the touch response and pharyngeal pumping in wild-type worm animals. Furthermore, in the presence of the drugs, both behaviors change to varying degrees in dopamine (dop-1, dop-2, and dop-3), serotonin (ser-1), and tyramine (ser-2) receptor-deficient mutants. This variation in response reveals specific targets for these antipsychotics in the nematode. Interestingly, their effect on behavior persisted to some extent in successive generations, indicating that they might induce epigenetic changes throughout development. Sodium butyrate, a histone deacetylase inhibitor, eliminated the consecutive generation effect of both drugs. In addition, these transgenerational effects were also abolished after the dauer stage. These observations suggest that risperidone and aripiprazole, in addition to interacting with specific receptors impairing the function of the nervous system of the nematode, may lead to the deposition of long-lasting epigenetic marks.
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Affiliation(s)
- Jaime Osuna-Luque
- Department of Genetics, University of Córdoba, Córdoba, Spain.,Maimónides Biomedical Research Institute of Córdoba (IMIBIC), Córdoba, Spain.,University Hospital Reina Sofía, Córdoba, Spain
| | - Ángel Rodríguez-Ramos
- Department of Genetics, University of Córdoba, Córdoba, Spain.,Maimónides Biomedical Research Institute of Córdoba (IMIBIC), Córdoba, Spain.,University Hospital Reina Sofía, Córdoba, Spain
| | - María Del Mar Gámez-Del-Estal
- Department of Genetics, University of Córdoba, Córdoba, Spain.,Maimónides Biomedical Research Institute of Córdoba (IMIBIC), Córdoba, Spain.,University Hospital Reina Sofía, Córdoba, Spain
| | - Manuel Ruiz-Rubio
- Department of Genetics, University of Córdoba, Córdoba, Spain.,Maimónides Biomedical Research Institute of Córdoba (IMIBIC), Córdoba, Spain.,University Hospital Reina Sofía, Córdoba, Spain
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15
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Two dopamine D2-like receptor genes from the silkworm (Bombyx mori) and their evolutionary history in metazoan. Sci Rep 2017; 7:6848. [PMID: 28754962 PMCID: PMC5533763 DOI: 10.1038/s41598-017-07055-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Accepted: 06/09/2017] [Indexed: 12/25/2022] Open
Abstract
Dopamine is widely distributed in metazoans and is implicated in many physiological functions. Dopaminergic signaling is mediated through two classes of dopamine receptors, D1-like and D2-like. Phylogeny analysis reveals that, the dopamine receptors probably appeared ahead of the cnidarian divergence, two distinct classes of dopamine receptors likely formed prior to the separation of deuterostomes and protostomes, and INDRs probably split from its ancestor before the emergence of nematodes. Two D2-like genes are closely linked on the same scaffold, and the chromosome region around D2-like gene loci show colinearity among different species within Lepidoptera. These indicate two D2-like and their adjunction genes are likely Lepidoptera-specific orthologs, and occur by gene duplication event taken place after Lepidoptera ancestor split from the common ancestor of Lepidoptera and Diptera. In silkworm, two D2-like genes were expressed in examined tissues, and encoded BmDop2R2 having all the features of D2-like receptors and BmDop2R1 being a truncated variant without the region of N-terminal to TM II. Only dopamine distinctly lowered cAMP levels in BmDop2R2-expressing cells, whereas all tested amines for BmDop2R1 had not markedly effect in pharmacological test. These suggest there is functional difference between the two genes, which are likely resulted from subfunctionalization of gene duplication.
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16
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Liu Y, Sun J. G protein-coupled receptors mediate neural regulation of innate immune responses in caenorhabditis elegans. RECEPTORS & CLINICAL INVESTIGATION 2017; 4:e1543. [PMID: 30386810 PMCID: PMC6206870 DOI: 10.14800/rci.1543] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
G protein-coupled receptors (GPCRs) are a large family of transmembrane proteins that perceive many extracellular signals and transduce them into cellular physiological responses. GPCRs regulate immunity in both vertebrates and invertebrates. However, the mechanisms responsible for such regulation are not fully understood. Recent research using the genetically tractable model organism Caenorhabditis elegans has led to the identification of specific GPCRs, neurotransmitters, neurons and non-neural cells in the regulation of innate immunity. Several neural circuits have been demonstrated to function in GPCR-dependent immuno-regulatory pathways. Besides being essential in neural-immune interactions, GPCRs also regulate innate immune response in non-neural tissues cell-autonomously through mechanisms independent of neural circuits. Here we review GPCR-mediated neural control of innate immunity in C. elegans and briefly discuss GPCR-dependent immune regulation via non-neural mechanisms.
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Affiliation(s)
- Yiyong Liu
- Department of Biomedical Sciences, Elson S. Floyd College of Medicine, Washington State University, Spokane, Washington, 99202, USA
| | - Jingru Sun
- Department of Biomedical Sciences, Elson S. Floyd College of Medicine, Washington State University, Spokane, Washington, 99202, USA
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17
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Ardiel EL, Giles AC, Yu AJ, Lindsay TH, Lockery SR, Rankin CH. Dopamine receptor DOP-4 modulates habituation to repetitive photoactivation of a C. elegans polymodal nociceptor. ACTA ACUST UNITED AC 2016; 23:495-503. [PMID: 27634141 PMCID: PMC5026203 DOI: 10.1101/lm.041830.116] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Accepted: 04/27/2016] [Indexed: 11/29/2022]
Abstract
Habituation is a highly conserved phenomenon that remains poorly understood at the molecular level. Invertebrate model systems, like Caenorhabditis elegans, can be a powerful tool for investigating this fundamental process. Here we established a high-throughput learning assay that used real-time computer vision software for behavioral tracking and optogenetics for stimulation of the C. elegans polymodal nociceptor, ASH. Photoactivation of ASH with ChR2 elicited backward locomotion and repetitive stimulation altered aspects of the response in a manner consistent with habituation. Recording photocurrents in ASH, we observed no evidence for light adaptation of ChR2. Furthermore, we ruled out fatigue by demonstrating that sensory input from the touch cells could dishabituate the ASH avoidance circuit. Food and dopamine signaling slowed habituation downstream from ASH excitation via D1-like dopamine receptor, DOP-4. This assay allows for large-scale genetic and drug screens investigating mechanisms of nociception modulation.
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Affiliation(s)
- Evan L Ardiel
- DM Centre for Brain Health, University of British Columbia, Vancouver V6T 2B5, Canada
| | - Andrew C Giles
- DM Centre for Brain Health, University of British Columbia, Vancouver V6T 2B5, Canada
| | - Alex J Yu
- DM Centre for Brain Health, University of British Columbia, Vancouver V6T 2B5, Canada
| | - Theodore H Lindsay
- Institute of Neuroscience, University of Oregon, Eugene, Oregon 97403, USA
| | - Shawn R Lockery
- Institute of Neuroscience, University of Oregon, Eugene, Oregon 97403, USA
| | - Catharine H Rankin
- DM Centre for Brain Health, University of British Columbia, Vancouver V6T 2B5, Canada Department of Psychology, University of British Columbia, Vancouver V6T 1Z4, Canada
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18
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Cao X, Aballay A. Neural Inhibition of Dopaminergic Signaling Enhances Immunity in a Cell-Non-autonomous Manner. Curr Biol 2016; 26:2329-34. [PMID: 27524480 DOI: 10.1016/j.cub.2016.06.036] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 05/10/2016] [Accepted: 06/16/2016] [Indexed: 12/20/2022]
Abstract
The innate immune system is the front line of host defense against microbial infections, but its rapid and uncontrolled activation elicits microbicidal mechanisms that have deleterious effects [1, 2]. Increasing evidence indicates that the metazoan nervous system, which responds to stimuli originating from both the internal and the external environment, functions as a modulatory apparatus that controls not only microbial killing pathways but also cellular homeostatic mechanisms [3-5]. Here we report that dopamine signaling controls innate immune responses through a D1-like dopamine receptor, DOP-4, in Caenorhabditis elegans. Chlorpromazine inhibition of DOP-4 in the nervous system activates a microbicidal PMK-1/p38 mitogen-activated protein kinase signaling pathway that enhances host resistance against bacterial infections. The immune inhibitory function of dopamine originates in CEP neurons and requires active DOP-4 in downstream ASG neurons. Our findings indicate that dopamine signaling from the nervous system controls immunity in a cell-non-autonomous manner and identifies the dopaminergic system as a potential therapeutic target for not only infectious diseases but also a range of conditions that arise as a consequence of malfunctioning immune responses.
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Affiliation(s)
- Xiou Cao
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Alejandro Aballay
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA.
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19
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Dopamine regulates body size in Caenorhabditis elegans. Dev Biol 2016; 412:128-138. [DOI: 10.1016/j.ydbio.2016.02.021] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Revised: 01/08/2016] [Accepted: 02/23/2016] [Indexed: 12/31/2022]
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20
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Likhite N, Jackson CA, Liang MS, Krzyzanowski MC, Lei P, Wood JF, Birkaya B, Michaels KL, Andreadis ST, Clark SD, Yu MC, Ferkey DM. The protein arginine methyltransferase PRMT5 promotes D2-like dopamine receptor signaling. Sci Signal 2015; 8:ra115. [PMID: 26554819 PMCID: PMC5473623 DOI: 10.1126/scisignal.aad0872] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Protein arginine methylation regulates diverse functions of eukaryotic cells, including gene expression, the DNA damage response, and circadian rhythms. We showed that arginine residues within the third intracellular loop of the human D2 dopamine receptor, which are conserved in the DOP-3 receptor in the nematode Caenorhabditis elegans, were methylated by protein arginine methyltransferase 5 (PRMT5). By mutating these arginine residues, we further showed that their methylation enhanced the D2 receptor-mediated inhibition of cyclic adenosine monophosphate (cAMP) signaling in cultured human embryonic kidney (HEK) 293T cells. Analysis of prmt-5-deficient worms indicated that methylation promoted the dopamine-mediated modulation of chemosensory and locomotory behaviors in C. elegans through the DOP-3 receptor. In addition to delineating a previously uncharacterized means of regulating GPCR (heterotrimeric guanine nucleotide-binding protein-coupled receptor) signaling, these findings may lead to the development of a new class of pharmacological therapies that modulate GPCR signaling by changing the methylation status of these key proteins.
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Affiliation(s)
- Neah Likhite
- Department of Biological Sciences, University at Buffalo, The State University of New York, Buffalo, NY 14260, USA
| | - Christopher A Jackson
- Department of Biological Sciences, University at Buffalo, The State University of New York, Buffalo, NY 14260, USA
| | - Mao-Shih Liang
- Bioengineering Laboratory, Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Buffalo, NY 14260, USA
| | - Michelle C Krzyzanowski
- Department of Biological Sciences, University at Buffalo, The State University of New York, Buffalo, NY 14260, USA
| | - Pedro Lei
- Bioengineering Laboratory, Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Buffalo, NY 14260, USA
| | - Jordan F Wood
- Department of Biological Sciences, University at Buffalo, The State University of New York, Buffalo, NY 14260, USA
| | - Barbara Birkaya
- Department of Biological Sciences, University at Buffalo, The State University of New York, Buffalo, NY 14260, USA
| | - Kerry L Michaels
- Department of Biological Sciences, University at Buffalo, The State University of New York, Buffalo, NY 14260, USA
| | - Stelios T Andreadis
- Bioengineering Laboratory, Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Buffalo, NY 14260, USA
| | - Stewart D Clark
- Department of Pharmacology and Toxicology, University at Buffalo, The State University of New York, Buffalo, NY 14214, USA. Department of Psychology, University at Buffalo, The State University of New York, Buffalo, NY 14214, USA. Research Institute on Addictions, University at Buffalo, The State University of New York, Buffalo, NY 14214, USA
| | - Michael C Yu
- Department of Biological Sciences, University at Buffalo, The State University of New York, Buffalo, NY 14260, USA.
| | - Denise M Ferkey
- Department of Biological Sciences, University at Buffalo, The State University of New York, Buffalo, NY 14260, USA.
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21
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Dallière N, Bhatla N, Luedtke Z, Ma DK, Woolman J, Walker RJ, Holden-Dye L, O'Connor V. Multiple excitatory and inhibitory neural signals converge to fine-tune Caenorhabditis elegans feeding to food availability. FASEB J 2015; 30:836-48. [PMID: 26514165 DOI: 10.1096/fj.15-279257] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 10/13/2015] [Indexed: 01/02/2023]
Abstract
How an animal matches feeding to food availability is a key question for energy homeostasis. We addressed this in the nematode Caenorhabditis elegans, which couples feeding to the presence of its food (bacteria) by regulating pharyngeal activity (pumping). We scored pumping in the presence of food and over an extended time course of food deprivation in wild-type and mutant worms to determine the neural substrates of adaptive behavior. Removal of food initially suppressed pumping but after 2 h this was accompanied by intermittent periods of high activity. We show pumping is fine-tuned by context-specific neural mechanisms and highlight a key role for inhibitory glutamatergic and excitatory cholinergic/peptidergic drives in the absence of food. Additionally, the synaptic protein UNC-31 [calcium-activated protein for secretion (CAPS)] acts through an inhibitory pathway not explained by previously identified contributions of UNC-31/CAPS to neuropeptide or glutamate transmission. Pumping was unaffected by laser ablation of connectivity between the pharyngeal and central nervous system indicating signals are either humoral or intrinsic to the enteric system. This framework in which control is mediated through finely tuned excitatory and inhibitory drives resonates with mammalian hypothalamic control of feeding and suggests that fundamental regulation of this basic animal behavior may be conserved through evolution from nematode to human.
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Affiliation(s)
- Nicolas Dallière
- *Centre for Biological Sciences, Faculty of Natural and Environmental Sciences, University of Southampton, Southampton, United Kingdom; and Howard Hughes Medical Institute and Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Nikhil Bhatla
- *Centre for Biological Sciences, Faculty of Natural and Environmental Sciences, University of Southampton, Southampton, United Kingdom; and Howard Hughes Medical Institute and Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Zara Luedtke
- *Centre for Biological Sciences, Faculty of Natural and Environmental Sciences, University of Southampton, Southampton, United Kingdom; and Howard Hughes Medical Institute and Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Dengke K Ma
- *Centre for Biological Sciences, Faculty of Natural and Environmental Sciences, University of Southampton, Southampton, United Kingdom; and Howard Hughes Medical Institute and Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Jonathan Woolman
- *Centre for Biological Sciences, Faculty of Natural and Environmental Sciences, University of Southampton, Southampton, United Kingdom; and Howard Hughes Medical Institute and Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Robert J Walker
- *Centre for Biological Sciences, Faculty of Natural and Environmental Sciences, University of Southampton, Southampton, United Kingdom; and Howard Hughes Medical Institute and Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Lindy Holden-Dye
- *Centre for Biological Sciences, Faculty of Natural and Environmental Sciences, University of Southampton, Southampton, United Kingdom; and Howard Hughes Medical Institute and Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Vincent O'Connor
- *Centre for Biological Sciences, Faculty of Natural and Environmental Sciences, University of Southampton, Southampton, United Kingdom; and Howard Hughes Medical Institute and Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
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DOP-2 D2-Like Receptor Regulates UNC-7 Innexins to Attenuate Recurrent Sensory Motor Neurons during C. elegans Copulation. J Neurosci 2015; 35:9990-10004. [PMID: 26156999 DOI: 10.1523/jneurosci.0940-15.2015] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
UNLABELLED Neuromodulation of self-amplifying circuits directs context-dependent behavioral executions. Although recurrent networks are found throughout the Caenorhabditis elegans connectome, few reports describe the mechanisms that regulate reciprocal neural activity during complex behavior. We used C. elegans male copulation to dissect how a goal-oriented motor behavior is regulated by recurrently wired sensory-motor neurons. As the male tail presses against the hermaphrodite's vulva, cholinergic and glutamatergic reciprocal innervations of post cloaca sensilla (PCS) neurons (PCA, PCB, and PCC), hook neurons (HOA, HOB), and their postsynaptic sex muscles execute rhythmic copulatory spicule thrusts. These repetitive spicule movements continue until the male shifts off the vulva or genital penetration is accomplished. However, the signaling mechanism that temporally and spatially restricts repetitive intromission attempts to vulva cues was unclear. Here, we report that confinement of spicule insertion attempts to the vulva is facilitated by D2-like receptor modulation of gap-junctions between PCB and the hook sensillum. We isolated a missense mutation in the UNC-7(L) gap-junction isoform, which perturbs DOP-2 signaling in the PCB neuron and its electrical partner, HOA. The glutamate-gated chloride channel AVR-14 is expressed in HOA. Our analysis of the unc-7 mutant allele indicates that when DOP-2 promotes UNC-7 electrical communication, AVR-14-mediated inhibitory signals pass from HOA to PCB. As a consequence, PCB is less receptive to be stimulated by its recurrent synaptic partner, PCA. Behavioral observations suggest that dopamine neuromodulation of UNC-7 ensures attenuation of recursive intromission attempts when the male disengages or is dislodged from the hermaphrodite genitalia. SIGNIFICANCE STATEMENT Using C. elegans male copulation as a model, we found that the neurotransmitter dopamine stimulates D2-like receptors in two sensory circuits to terminate futile behavioral loops. The D2-like receptors promote inhibitory electrical junction activity between a chemosensory and a mechanosensory circuit. Therefore, both systems are attenuated and the animal ceases the recursive behavior.
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23
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Wang D, Yu Y, Li Y, Wang Y, Wang D. Dopamine receptors antagonistically regulate behavioral choice between conflicting alternatives in C. elegans. PLoS One 2014; 9:e115985. [PMID: 25536037 PMCID: PMC4275273 DOI: 10.1371/journal.pone.0115985] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Accepted: 12/03/2014] [Indexed: 11/18/2022] Open
Abstract
Caenorhabditis elegans is a useful model to study the neuronal or molecular basis for behavioral choice, a specific form of decision-making. Although it has been implied that both D1-like and D2-like dopamine receptors may contribute to the control of decision-making in mammals, the genetic interactions between D1-like and D2-like dopamine receptors in regulating decision-making are still largely unclear. In the present study, we investigated the molecular control of behavioral choice between conflicting alternatives (diacetyl and Cu2+) by D1-like and D2-like dopamine receptors and their possible genetic interactions with C. elegans as the assay system. In the behavioral choice assay system, mutation of dop-1 gene encoding D1-like dopamine receptor resulted in the enhanced tendency to cross the Cu2+ barrier compared with wild-type. In contrast, mutations of dop-2 or dop-3 gene encoding D2-like dopamine receptor caused the weak tendency to cross the Cu2+ barrier compared with wild-type. During the control of behavioral choice, DOP-3 antagonistically regulated the function of DOP-1. The behavioral choice phenotype of dop-2; dop-1dop-3 triple mutant further confirmed the possible antagonistic function of D2-like dopamine receptor on D1-like dopamine receptor in regulating behavioral choice. The genetic assays further demonstrate that DOP-3 might act through Gαo signaling pathway encoded by GOA-1 and EGL-10, and DOP-1 might act through Gαq signaling pathway encoded by EGL-30 and EAT-16 to regulate the behavioral choice. DOP-1 might function in cholinergic neurons to regulate the behavioral choice, whereas DOP-3 might function in GABAergic neurons, RIC, and SIA neurons to regulate the behavioral choice. In this study, we provide the genetic evidence to indicate the antagonistic relationship between D1-like dopamine receptor and D2-like dopamine receptor in regulating the decision-making of animals. Our data will be useful for understanding the complex functions of dopamine receptors in regulating decision-making in animals.
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Affiliation(s)
- Daoyong Wang
- Key Laboratory of Developmental Genes and Human Disease in Ministry of Education, Medical School of Southeast University, Nanjing, 210009, China
| | - Yonglin Yu
- Key Laboratory of Developmental Genes and Human Disease in Ministry of Education, Medical School of Southeast University, Nanjing, 210009, China
| | - Yinxia Li
- Key Laboratory of Developmental Genes and Human Disease in Ministry of Education, Medical School of Southeast University, Nanjing, 210009, China
| | - Yang Wang
- Key Laboratory of Developmental Genes and Human Disease in Ministry of Education, Medical School of Southeast University, Nanjing, 210009, China
| | - Dayong Wang
- Key Laboratory of Developmental Genes and Human Disease in Ministry of Education, Medical School of Southeast University, Nanjing, 210009, China
- * E-mail:
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Amphetamine potentiates the effects of β-phenylethylamine through activation of an amine-gated chloride channel. J Neurosci 2014; 34:4686-91. [PMID: 24672014 DOI: 10.1523/jneurosci.3100-13.2014] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
β-Phenylethylamine (βPEA) is a trace amine present in the CNS of all animals tested to date. However, its function is still not fully understood. βPEA has been suggested to function as a neurotransmitter and/or to mimic the effect of amphetamine (Amph). In support of the latter is the observation that βPEA and Amph produce similar but not identical behaviors. Here, we show that βPEA, like Amph, activates the dopamine transporter and the amine-gated chloride channel LGC-55 to generate behaviors in Caenorhabditis elegans. However, although Amph-induced behaviors occurred gradually during 10 min of treatment, βPEA induced maximal effects within 1 min. In vitro data demonstrate that βPEA activates the LGC-55 more efficiently than Amph (Km = 9 and 152 μm, respectively) and generates saturating currents that are 10 times larger than those produced by Amph. These results suggest that activation of LGC-55 mostly accounts for the behavioral effects reached after 1 min of treatment with βPEA. Importantly, our in vitro and in vivo data show that Amph increases the effects induced by βPEA on the LGC-55, indicating that Amph potentiates the effects generated by the biogenic amine βPEA. Together, our data not only identify a new target for βPEA, but also offer a novel mechanism of action of Amph. In addition, our results highlight C. elegans as a powerful genetic model for studying the effects of biogenic and synthetic amines both at the molecular and behavioral levels.
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Dopamine signaling in C. elegans is mediated in part by HLH-17-dependent regulation of extracellular dopamine levels. G3-GENES GENOMES GENETICS 2014; 4:1081-9. [PMID: 24709946 PMCID: PMC4065251 DOI: 10.1534/g3.114.010819] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In Caenorhabditis elegans, the dopamine transporter DAT-1 regulates synaptic dopamine (DA) signaling by controlling extracellular DA levels. In dat-1(ok157) animals, DA is not taken back up presynaptically but instead reaches extrasynpatic sites, where it activates the dopamine receptor DOP-3 on choligeneric motor neurons and causes animals to become paralyzed in water. This phenotype is called swimming-induced paralysis (SWIP) and is dependent on dat-1 and dop-3. Upstream regulators of dat-1 and dop-3 have yet to be described in C. elegans. In our previous studies, we defined a role for HLH-17 during dopamine response through its regulation of the dopamine receptors. Here we continue our characterization of the effects of HLH-17 on dopamine signaling. Our results suggest that HLH-17 acts downstream of dopamine synthesis to regulate the expression of dop-3 and dat-1. First, we show that hlh-17 animals display a SWIP phenotype that is consistent with its regulation of dop-3 and dat-1. Second, we show that this behavior is enhanced by treatment with the dopamine reuptake inhibitor, bupropion, in both hlh-17 and dat-1 animals, a result suggesting that SWIP behavior is regulated via a mechanism that is both dependent on and independent of DAT-1. Third, and finally, we show that although the SWIP phenotype of hlh-17 animals is unresponsive to the dopamine agonist, reserpine, and to the antidepressant, fluoxetine, hlh-17 animals are not defective in acetylcholine signaling. Taken together, our work suggests that HLH-17 is required to maintain normal levels of dopamine in the synaptic cleft through its regulation of dop-3 and dat-1.
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Topper SM, Aguilar SC, Topper VY, Elbel E, Pierce-Shimomura JT. Alcohol disinhibition of behaviors in C. elegans. PLoS One 2014; 9:e92965. [PMID: 24681782 PMCID: PMC3969370 DOI: 10.1371/journal.pone.0092965] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2013] [Accepted: 02/27/2014] [Indexed: 11/30/2022] Open
Abstract
Alcohol has a wide variety of effects on physiology and behavior. One of the most well-recognized behavioral effects is disinhibition, where behaviors that are normally suppressed are displayed following intoxication. A large body of evidence has shown that alcohol-induced disinhibition in humans affects attention, verbal, sexual, and locomotor behaviors. Similar behavioral disinhibition is also seen in many animal models of ethanol response, from invertebrates to mammals and primates. Here we describe several examples of disinhibition in the nematode C. elegans. The nematode displays distinct behavioral states associated with locomotion (crawling on land and swimming in water) that are mediated by dopamine. On land, animals crawl and feed freely, but these behaviors are inhibited in water. We found that additional behaviors, including a variety of escape responses are also inhibited in water. Whereas alcohol non-specifically impaired locomotion, feeding, and escape responses in worms on land, alcohol specifically disinhibited these behaviors in worms immersed in water. Loss of dopamine signaling relieved disinhibition of feeding behavior, while loss of the D1-like dopamine receptor DOP-4 impaired the ethanol-induced disinhibition of crawling. The powerful genetics and simple nervous system of C. elegans may help uncover conserved molecular mechanisms that underlie alcohol-induced disinhibition of behaviors in higher animals.
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Affiliation(s)
- Stephen M. Topper
- Waggoner Center for Alcohol and Addiction Research, Cell & Molecular Biology, Department of Neuroscience, The University of Texas at Austin, Austin, Texas, United States of America
| | - Sara C. Aguilar
- Waggoner Center for Alcohol and Addiction Research, Cell & Molecular Biology, Department of Neuroscience, The University of Texas at Austin, Austin, Texas, United States of America
| | - Viktoria Y. Topper
- Waggoner Center for Alcohol and Addiction Research, Cell & Molecular Biology, Department of Neuroscience, The University of Texas at Austin, Austin, Texas, United States of America
| | - Erin Elbel
- Waggoner Center for Alcohol and Addiction Research, Cell & Molecular Biology, Department of Neuroscience, The University of Texas at Austin, Austin, Texas, United States of America
| | - Jonathan T. Pierce-Shimomura
- Waggoner Center for Alcohol and Addiction Research, Cell & Molecular Biology, Department of Neuroscience, The University of Texas at Austin, Austin, Texas, United States of America
- * E-mail:
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Barros AGDA, Bridi JC, de Souza BR, de Castro Júnior C, de Lima Torres KC, Malard L, Jorio A, de Miranda DM, Ashrafi K, Romano-Silva MA. Dopamine signaling regulates fat content through β-oxidation in Caenorhabditis elegans. PLoS One 2014; 9:e85874. [PMID: 24465759 PMCID: PMC3899111 DOI: 10.1371/journal.pone.0085874] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2013] [Accepted: 12/06/2013] [Indexed: 11/26/2022] Open
Abstract
The regulation of energy balance involves an intricate interplay between neural mechanisms that respond to internal and external cues of energy demand and food availability. Compelling data have implicated the neurotransmitter dopamine as an important part of body weight regulation. However, the precise mechanisms through which dopamine regulates energy homeostasis remain poorly understood. Here, we investigate mechanisms through which dopamine modulates energy storage. We showed that dopamine signaling regulates fat reservoirs in Caenorhabditis elegans. We found that the fat reducing effects of dopamine were dependent on dopaminergic receptors and a set of fat oxidation enzymes. Our findings reveal an ancient role for dopaminergic regulation of fat and suggest that dopamine signaling elicits this outcome through cascades that ultimately mobilize peripheral fat depots.
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Affiliation(s)
- Alexandre Guimarães de Almeida Barros
- Instituto Nacional de Ciência e Tecnologia de Medicina Molecular, Faculdade de Medicina da Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Jessika Cristina Bridi
- Instituto Nacional de Ciência e Tecnologia de Medicina Molecular, Faculdade de Medicina da Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Bruno Rezende de Souza
- Departamento de Fisiologia e Biofísica, Instituto de Ciências Biológicas da Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Célio de Castro Júnior
- Instituto Nacional de Ciência e Tecnologia de Medicina Molecular, Faculdade de Medicina da Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Karen Cecília de Lima Torres
- Instituto Nacional de Ciência e Tecnologia de Medicina Molecular, Faculdade de Medicina da Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Leandro Malard
- Departamento de Física, Instituto de Ciências Exatas da Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Ado Jorio
- Departamento de Física, Instituto de Ciências Exatas da Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Débora Marques de Miranda
- Instituto Nacional de Ciência e Tecnologia de Medicina Molecular, Faculdade de Medicina da Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Kaveh Ashrafi
- Department of Physiology, University of California San Francisco, San Francisco, California, United States
| | - Marco Aurélio Romano-Silva
- Instituto Nacional de Ciência e Tecnologia de Medicina Molecular, Faculdade de Medicina da Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
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Characterization of an invertebrate-type dopamine receptor of the American cockroach, Periplaneta americana. Int J Mol Sci 2014; 15:629-53. [PMID: 24398985 PMCID: PMC3907829 DOI: 10.3390/ijms15010629] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Revised: 12/20/2013] [Accepted: 12/24/2013] [Indexed: 12/22/2022] Open
Abstract
We have isolated a cDNA coding for a putative invertebrate-type dopamine receptor (Peadop2) from P. americana brain by using a PCR-based strategy. The mRNA is present in samples from brain and salivary glands. We analyzed the distribution of the PeaDOP2 receptor protein with specific affinity-purified polyclonal antibodies. On Western blots, PeaDOP2 was detected in protein samples from brain, subesophageal ganglion, thoracic ganglia, and salivary glands. In immunocytochemical experiments, we detected PeaDOP2 in neurons with their somata being located at the anterior edge of the medulla bilaterally innervating the optic lobes and projecting to the ventro-lateral protocerebrum. In order to determine the functional and pharmacological properties of the cloned receptor, we generated a cell line constitutively expressing PeaDOP2. Activation of PeaDOP2-expressing cells with dopamine induced an increase in intracellular cAMP. In contrast, a C-terminally truncated splice variant of this receptor did not exhibit any functional property by itself. The molecular and pharmacological characterization of the first dopamine receptor from P. americana provides the basis for forthcoming studies focusing on the significance of the dopaminergic system in cockroach behavior and physiology.
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Function and distribution of 5-HT2 receptors in the honeybee (Apis mellifera). PLoS One 2013; 8:e82407. [PMID: 24324783 PMCID: PMC3855752 DOI: 10.1371/journal.pone.0082407] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Accepted: 10/23/2013] [Indexed: 11/27/2022] Open
Abstract
Background Serotonin plays a pivotal role in regulating and modulating physiological and behavioral processes in both vertebrates and invertebrates. In the honeybee (Apis mellifera), serotonin has been implicated in division of labor, visual processing, and learning processes. Here, we present the cloning, heterologous expression, and detailed functional and pharmacological characterization of two honeybee 5-HT2 receptors. Methods Honeybee 5-HT2 receptor cDNAs were amplified from brain cDNA. Recombinant cell lines were established constitutively expressing receptor variants. Pharmacological properties of the receptors were investigated by Ca2+ imaging experiments. Quantitative PCR was applied to explore the expression patterns of receptor mRNAs. Results The honeybee 5-HT2 receptor class consists of two subtypes, Am5-HT2α and Am5-HT2β. Each receptor gene also gives rise to alternatively spliced mRNAs that possibly code for truncated receptors. Only activation of the full-length receptors with serotonin caused an increase in the intracellular Ca2+ concentration. The effect was mimicked by the agonists 5-methoxytryptamine and 8-OH-DPAT at low micromolar concentrations. Receptor activities were blocked by established 5-HT receptor antagonists such as clozapine, methiothepin, or mianserin. High transcript numbers were detected in exocrine glands suggesting that 5-HT2 receptors participate in secretory processes in the honeybee. Conclusions This study marks the first molecular and pharmacological characterization of two 5-HT2 receptor subtypes in the same insect species. The results presented should facilitate further attempts to unravel central and peripheral effects of serotonin mediated by these receptors.
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Bayliss AL, Evans PD. Characterisation of AmphiAmR11, an amphioxus (Branchiostoma floridae) D2-dopamine-like G protein-coupled receptor. PLoS One 2013; 8:e80833. [PMID: 24265838 PMCID: PMC3827198 DOI: 10.1371/journal.pone.0080833] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2013] [Accepted: 10/08/2013] [Indexed: 11/20/2022] Open
Abstract
The evolution of the biogenic amine signalling system in vertebrates is unclear. However, insights can be obtained from studying the structures and signalling properties of biogenic amine receptors from the protochordate, amphioxus, which is an invertebrate species that exists at the base of the chordate lineage. Here we describe the signalling properties of AmphiAmR11, an amphioxus (Branchiostoma floridae) G protein-coupled receptor which has structural similarities to vertebrate α2-adrenergic receptors but which functionally acts as a D2 dopamine-like receptor when expressed in Chinese hamster ovary -K1 cells. AmphiAmR11 inhibits forskolin-stimulated cyclic AMP levels with tyramine, phenylethylamine and dopamine being the most potent agonists. AmphiAmR11 also increases mitogen-activated protein kinase activity and calcium mobilisation, and in both pathways, dopamine was found to be more potent than tyramine. Thus, differences in the relative effectiveness of various agonists in the different second messenger assay systems suggest that the receptor displays agonist-specific coupling (biased agonism) whereby different agonists stabilize different conformations of the receptor which lead to the enhancement of one signalling pathway over another. The present study provides insights into the evolution of α2-adrenergic receptor signalling and support the hypothesis that α2-adrenergic receptors evolved from D2-dopamine receptors. The AmphiAmR11 receptor may represent a transition state between D2-dopamine receptors and α2-adrenergic receptors.
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MESH Headings
- Adenylyl Cyclases/metabolism
- Animals
- CHO Cells
- Calcium/metabolism
- Calcium Signaling/drug effects
- Cricetulus
- Cyclic AMP/metabolism
- Dopamine D2 Receptor Antagonists
- Lancelets/genetics
- Lancelets/metabolism
- Mitogen-Activated Protein Kinases/metabolism
- Pertussis Toxin/pharmacology
- Receptors, Biogenic Amine/agonists
- Receptors, Biogenic Amine/antagonists & inhibitors
- Receptors, Biogenic Amine/genetics
- Receptors, Biogenic Amine/metabolism
- Receptors, Dopamine D2/agonists
- Receptors, Dopamine D2/genetics
- Receptors, Dopamine D2/metabolism
- Receptors, G-Protein-Coupled/agonists
- Receptors, G-Protein-Coupled/antagonists & inhibitors
- Receptors, G-Protein-Coupled/genetics
- Receptors, G-Protein-Coupled/metabolism
- Signal Transduction/drug effects
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Affiliation(s)
- Asha L. Bayliss
- The Signalling Laboratory, the Babraham Institute, Cambridge, United Kingdom
| | - Peter D. Evans
- The Signalling Laboratory, the Babraham Institute, Cambridge, United Kingdom
- * E-mail:
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Suo S, Ishiura S. Dopamine modulates acetylcholine release via octopamine and CREB signaling in Caenorhabditis elegans. PLoS One 2013; 8:e72578. [PMID: 23977320 PMCID: PMC3745381 DOI: 10.1371/journal.pone.0072578] [Citation(s) in RCA: 15] [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: 03/17/2013] [Accepted: 07/10/2013] [Indexed: 11/18/2022] Open
Abstract
Animals change their behavior and metabolism in response to external stimuli. cAMP response element binding protein (CREB) is a signal-activated transcription factor that enables the coupling of extracellular signals and gene expression to induce adaptive changes. Biogenic amine neurotransmitters regulate CREB and such regulation is important for long-term changes in various nervous system functions, including learning and drug addiction. In Caenorhabditis elegans, the amine neurotransmitter octopamine activates a CREB homolog, CRH-1, in cholinergic SIA neurons, whereas dopamine suppresses CREB activation by inhibiting octopamine signaling in response to food stimuli. However, the physiological role of this activation is unknown. In this study, the effect of dopamine, octopamine, and CREB on acetylcholine signaling was analyzed using the acetylcholinesterase inhibitor aldicarb. Mutants with decreased dopamine signaling exhibited reduced acetylcholine signaling, and octopamine and CREB functioned downstream of dopamine in this regulation. This study demonstrates that the regulation of CREB by amine neurotransmitters modulates acetylcholine release from the neurons of C. elegans.
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Affiliation(s)
- Satoshi Suo
- Department of Life Sciences, Graduate School of Arts & Sciences, University of Tokyo, Tokyo, Japan.
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32
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Correa P, LeBoeuf B, García LR. C. elegans dopaminergic D2-like receptors delimit recurrent cholinergic-mediated motor programs during a goal-oriented behavior. PLoS Genet 2012; 8:e1003015. [PMID: 23166505 PMCID: PMC3499252 DOI: 10.1371/journal.pgen.1003015] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2012] [Accepted: 08/22/2012] [Indexed: 11/18/2022] Open
Abstract
Caenorhabditis elegans male copulation requires coordinated temporal-spatial execution of different motor outputs. During mating, a cloacal circuit consisting of cholinergic sensory-motor neurons and sex muscles maintains the male's position and executes copulatory spicule thrusts at his mate's vulva. However, distinct signaling mechanisms that delimit these behaviors to their proper context are unclear. We found that dopamine (DA) signaling directs copulatory spicule insertion attempts to the hermaphrodite vulva by dampening spurious stimulus-independent sex muscle contractions. From pharmacology and genetic analyses, DA antagonizes stimulatory ACh signaling via the D2-like receptors, DOP-2 and DOP-3, and Gα(o/i) proteins, GOA-1 and GPA-7. Calcium imaging and optogenetics suggest that heightened DA-expressing ray neuron activities coincide with the cholinergic cloacal ganglia function during spicule insertion attempts. D2-like receptor signaling also attenuates the excitability of additional mating circuits to reduce the duration of mating attempts with unproductive and/or inappropriate partners. This suggests that, during wild-type mating, simultaneous DA-ACh signaling modulates the activity threshold of repetitive motor programs, thus confining the behavior to the proper situational context.
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Affiliation(s)
- Paola Correa
- Department of Biology, Texas A&M University, College Station, Texas, United States of America
| | - Brigitte LeBoeuf
- Department of Biology, Texas A&M University, College Station, Texas, United States of America
- Howard Hughes Medical Institute, College Station, Texas, United States of America
| | - L. René García
- Department of Biology, Texas A&M University, College Station, Texas, United States of America
- Howard Hughes Medical Institute, College Station, Texas, United States of America
- * E-mail:
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Abstract
Dopamine is an ancient signaling molecule. It is responsible for maintaining the adaptability of behavioral outputs and is found across taxa. The following is a summary of the role of dopamine and the mechanisms of its function and dysfunction. We discuss our recent findings on dopaminergic control of behaviors in C. elegans and discuss its potential implications for work in the fields of C. elegans and Parkinson research.
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Forward genetic analysis to identify determinants of dopamine signaling in Caenorhabditis elegans using swimming-induced paralysis. G3-GENES GENOMES GENETICS 2012; 2:961-75. [PMID: 22908044 PMCID: PMC3411251 DOI: 10.1534/g3.112.003533] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/07/2012] [Accepted: 06/23/2012] [Indexed: 11/20/2022]
Abstract
Disrupted dopamine (DA) signaling is believed to contribute to the core features of multiple neuropsychiatric and neurodegenerative disorders. Essential features of DA neurotransmission are conserved in the nematode Caenorhabditis elegans, providing us with an opportunity to implement forward genetic approaches that may reveal novel, in vivo regulators of DA signaling. Previously, we identified a robust phenotype, termed Swimming-induced paralysis (Swip), that emerges in animals deficient in the plasma membrane DA transporter. Here, we report the use and quantitative analysis of Swip in the identification of mutant genes that control DA signaling. Two lines captured in our screen (vt21 and vt22) bear novel dat-1 alleles that disrupt expression and surface trafficking of transporter proteins in vitro and in vivo. Two additional lines, vt25 and vt29, lack transporter mutations but exhibit genetic, biochemical, and behavioral phenotypes consistent with distinct perturbations of DA signaling. Our studies validate the utility of the Swip screen, demonstrate the functional relevance of DA transporter structural elements, and reveal novel genomic loci that encode regulators of DA signaling.
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Li Y, Yu S, Wu Q, Tang M, Wang D. Transmissions of serotonin, dopamine, and glutamate are required for the formation of neurotoxicity from Al2O3-NPs in nematodeCaenorhabditis elegans. Nanotoxicology 2012; 7:1004-13. [DOI: 10.3109/17435390.2012.689884] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Komuniecki R, Harris G, Hapiak V, Wragg R, Bamber B. Monoamines activate neuropeptide signaling cascades to modulate nociception in C. elegans: a useful model for the modulation of chronic pain? INVERTEBRATE NEUROSCIENCE 2011; 12:53-61. [PMID: 22143253 DOI: 10.1007/s10158-011-0127-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2011] [Accepted: 11/15/2011] [Indexed: 12/13/2022]
Abstract
Monoamines and neuropeptides interact to modulate key behaviors in most organisms. This review is focused on the interaction between octopamine (OA) and an array of neuropeptides in the inhibition of a simple, sensory-mediated aversive behavior in the C. elegans model system and describes the role of monoamines in the activation of global peptidergic signaling cascades. OA has been often considered the invertebrate counterpart of norepinephrine, and the review also highlights the similarities between OA inhibition in C. elegans and the noradrenergic modulation of pain in higher organisms.
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Affiliation(s)
- Rick Komuniecki
- Department of Biological Sciences, University of Toledo, 2801 W. Bancroft Street, Toledo, OH 43606, USA.
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Felton CM, Johnson CM. Modulation of dopamine-dependent behaviors by the Caenorhabditis elegans Olig homolog HLH-17. J Neurosci Res 2011; 89:1627-36. [DOI: 10.1002/jnr.22694] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2010] [Revised: 04/12/2011] [Accepted: 04/15/2011] [Indexed: 11/08/2022]
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Coexpressed D1- and D2-like dopamine receptors antagonistically modulate acetylcholine release in Caenorhabditis elegans. Genetics 2011; 188:579-90. [PMID: 21515580 DOI: 10.1534/genetics.111.128512] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Dopamine acts through two classes of G protein-coupled receptor (D1-like and D2-like) to modulate neuron activity in the brain. While subtypes of D1- and D2-like receptors are coexpressed in many neurons of the mammalian brain, it is unclear how signaling by these coexpressed receptors interacts to modulate the activity of the neuron in which they are expressed. D1- and D2-like dopamine receptors are also coexpressed in the cholinergic ventral-cord motor neurons of Caenorhabditis elegans. To begin to understand how coexpressed dopamine receptors interact to modulate neuron activity, we performed a genetic screen in C. elegans and isolated mutants defective in dopamine response. These mutants were also defective in behaviors mediated by endogenous dopamine signaling, including basal slowing and swimming-induced paralysis. We used transgene rescue experiments to show that defects in these dopamine-specific behaviors were caused by abnormal signaling in the cholinergic motor neurons. To investigate the interaction between the D1- and D2-like receptors specifically in these cholinergic motor neurons, we measured the sensitivity of dopamine-signaling mutants and transgenic animals to the acetylcholinesterase inhibitor aldicarb. We found that D2 signaling inhibited acetylcholine release from the cholinergic motor neurons while D1 signaling stimulated release from these same cells. Thus, coexpressed D1- and D2-like dopamine receptors act antagonistically in vivo to modulate acetylcholine release from the cholinergic motor neurons of C. elegans.
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Ezcurra M, Tanizawa Y, Swoboda P, Schafer WR. Food sensitizes C. elegans avoidance behaviours through acute dopamine signalling. EMBO J 2011; 30:1110-22. [PMID: 21304491 DOI: 10.1038/emboj.2011.22] [Citation(s) in RCA: 102] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2010] [Accepted: 01/07/2011] [Indexed: 01/28/2023] Open
Abstract
Many behavioural states are modulated by food availability and nutritional status. Here, we report that in Caenorhabditis elegans, the presence of an external food source enhances avoidance responses to soluble repellents sensed by the polymodal ASH neurons. This enhancement requires dopamine signalling and is mimicked by exogenous dopamine. Food modulation is dependent on the mechanosensory cilia of the dopaminergic neurons, indicating that dopamine is released in response to sensation of bacteria. Activation of the dopamine neurons leads within seconds to a transient state of increased sensory acuity. In vivo imaging experiments indicate that this dopamine-dependent sensitization results in part from modality-specific increases in the magnitude and duration of gustatory responses in the ASH neurons. The D1-like dopamine receptor DOP-4 acts cell autonomously in ASH to mediate effects on response magnitude. Thus, dopamine functions as a direct signal of the presence of food to control context-dependent behavioural states.
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Affiliation(s)
- Marina Ezcurra
- Cell Biology Division, MRC Laboratory of Molecular Biology, Cambridge, UK
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40
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Enhancement of odor avoidance regulated by dopamine signaling in Caenorhabditis elegans. J Neurosci 2011; 30:16365-75. [PMID: 21123582 DOI: 10.1523/jneurosci.6023-09.2010] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
The enhancement of sensory responses after prior exposure to a stimulus is a fundamental mechanism of neural function in animals. Its molecular basis, however, has not been studied in as much depth as the reduction of sensory responses, such as adaptation or habituation. We report here that the avoidance behavior of the nematode Caenorhabditis elegans in response to repellent odors (2-nonanone or 1-octanol) is enhanced rather than reduced after preexposure to the odors. This enhancement effect of preexposure was maintained for at least 1 h after the conditioning. The enhancement of 2-nonanone avoidance was not dependent on the presence or absence of food during conditioning, which generally functions as a strong positive or negative unconditioned stimulus in the animals. These results suggest that the enhancement is acquired as a type of nonassociative learning. In addition, genetic and pharmacological analyses revealed that the enhancement of 2-nonanone avoidance requires dopamine signaling via D(2)-like dopamine receptor DOP-3, which functions in a pair of RIC interneurons to regulate the enhancement. Because dopamine signaling has been tightly linked with food-related information to modulate various behaviors of C. elegans, it may play different role in the regulation of the enhancement of 2-nonanone avoidance. Thus, our data suggest a new genetic and pharmacological paradigm for nonassociative enhancement of neural responses that is regulated by dopamine signaling.
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Carvelli L, Matthies DS, Galli A. Molecular mechanisms of amphetamine actions in Caenorhabditis elegans. Mol Pharmacol 2010; 78:151-6. [PMID: 20410438 DOI: 10.1124/mol.109.062703] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Amphetamine (AMPH) poses a serious hazard to public health. Defining the molecular targets of AMPH is essential to developing treatments for psychostimulant abuse. AMPH elicits its behavioral effects primarily by increasing extracellular dopamine (DA) levels through the reversal of the DA transporter (DAT) cycle and, as a consequence, altering DA signaling. In Caenorhabditis elegans, an excess of synaptic DA results in a loss of motility in water, termed swimming-induced paralysis (SWIP). Here we demonstrate that AMPH produces SWIP in a time- and dose-dependent manner in wild-type (wt) animals but has a reduced ability to generate SWIP in DAT knock out worms (dat-1). To determine whether D1-like and/or D2-like receptors are involved in AMPH-induced SWIP, we performed experiments in DOP-1 and DOP-4, and DOP-2, and DOP-3 receptor knockout animals, respectively. AMPH administration resulted in a reduced ability to induce SWIP in animals lacking DOP-3, DOP-4, and DOP-2 receptors. In contrast, in worms lacking DOP-1 receptors, AMPH-induced SWIP occurred at wt levels. Using microamperometry on C. elegans DA neurons, we determined that in contrast to wt cells, AMPH failed to promote DA efflux in dat-1 DA neurons. These data suggest that DA efflux is critical to sustaining SWIP behavior by signaling through DOP-3, DOP-4, and DOP-2. In a double mutant lacking both DAT-1 and DOP-1 expression, we found no ability of AMPH to induce SWIP or DA efflux. This result supports the paradigm that DA efflux through C. elegans DAT is required for AMPH-induced behaviors and does not require DOP-1 signaling.
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Affiliation(s)
- Lucia Carvelli
- Department of Pharmacology, Physiology and Therapeutics, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, North Dakota, USA
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42
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Ezak MJ, Ferkey DM. The C. elegans D2-like dopamine receptor DOP-3 decreases behavioral sensitivity to the olfactory stimulus 1-octanol. PLoS One 2010; 5:e9487. [PMID: 20209143 PMCID: PMC2830454 DOI: 10.1371/journal.pone.0009487] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2009] [Accepted: 02/10/2010] [Indexed: 11/19/2022] Open
Abstract
We previously found that dopamine signaling modulates the sensitivity of wild-type C. elegans to the aversive odorant 1-octanol. C. elegans lacking the CAT-2 tyrosine hydroxylase enzyme, which is required for dopamine biosynthesis, are hypersensitive in their behavioral avoidance of dilute concentrations of octanol. Dopamine can also modulate the context-dependent response of C. elegans lacking RGS-3 function, a negative regulator of G alpha signaling. rgs-3 mutant animals are defective in their avoidance of 100% octanol when they are assayed in the absence of food (E. coli bacterial lawn), but their response is restored when they are assayed in the presence of food or exogenous dopamine. However, it is not known which receptor might be mediating dopamine's effects on octanol avoidance. Herein we describe a role for the C. elegans D2-like receptor DOP-3 in the regulation of olfactory sensitivity. We show that DOP-3 is required for the ability of food and exogenous dopamine to rescue the octanol avoidance defect of rgs-3 mutant animals. In addition, otherwise wild-type animals lacking DOP-3 function are hypersensitive to dilute octanol, reminiscent of cat-2 mutants. Furthermore, we demonstrate that DOP-3 function in the ASH sensory neurons is sufficient to rescue the hypersensitivity of dop-3 mutant animals, while dop-3 RNAi knockdown in ASH results in octanol hypersensitivity. Taken together, our data suggest that dopaminergic signaling through DOP-3 normally acts to dampen ASH signaling and behavioral sensitivity to octanol.
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Affiliation(s)
- Meredith J. Ezak
- Department of Biological Sciences, State University of New York at Buffalo, Buffalo, New York, United States of America
| | - Denise M. Ferkey
- Department of Biological Sciences, State University of New York at Buffalo, Buffalo, New York, United States of America
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Suo S, Culotti JG, Van Tol HHM. Dopamine suppresses octopamine signaling in C. elegans: possible involvement of dopamine in the regulation of lifespan. Aging (Albany NY) 2009; 1:870-4. [PMID: 20157560 PMCID: PMC2815730 DOI: 10.18632/aging.100097] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2009] [Accepted: 10/19/2009] [Indexed: 02/01/2023]
Abstract
Amine neurotransmitters, such as dopamine, serotonin, and noradrenaline, play important roles in the modulation of behaviors and metabolism of animals. InC. elegans, it has been shown that serotonin and octopamine, an invertebrate equivalent of noradrenaline, also regulate lifespan through a mechanism related to food deprivation-mediated lifespan extension. We have shown recently that dopamine signaling, activated by the tactile perception of food, suppresses octopamine signaling and that the cessation of dopamine signaling in the absence of food leads to activation of octopamine signaling. Here, we discuss the apparent conservation of neural and molecular mechanisms for dopamine regulation of octopamine/noradrenaline signaling and a possible role for dopamine in lifespan regulation.
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Affiliation(s)
- Satoshi Suo
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada, M5G 1X5.
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Dopamine counteracts octopamine signalling in a neural circuit mediating food response in C. elegans. EMBO J 2009; 28:2437-48. [PMID: 19609300 DOI: 10.1038/emboj.2009.194] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2009] [Accepted: 06/17/2009] [Indexed: 01/02/2023] Open
Abstract
Animals assess food availability in their environment by sensory perception and respond to the absence of food by changing hormone and neurotransmitter signals. However, it is largely unknown how the absence of food is perceived at the level of functional neurocircuitry. In Caenorhabditis elegans, octopamine is released from the RIC neurons in the absence of food and activates the cyclic AMP response element binding protein in the cholinergic SIA neurons. In contrast, dopamine is released from dopaminergic neurons only in the presence of food. Here, we show that dopamine suppresses octopamine signalling through two D2-like dopamine receptors and the G protein Gi/o. The D2-like receptors work in both the octopaminergic neurons and the octopamine-responding SIA neurons, suggesting that dopamine suppresses octopamine release as well as octopamine-mediated downstream signalling. Our results show that C. elegans detects the absence of food by using a small neural circuit composed of three neuron types in which octopaminergic signalling is activated by the cessation of dopamine signalling.
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45
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Stimulation of movement in a quiescent, hibernation-like form of Caenorhabditis elegans by dopamine signaling. J Neurosci 2009; 29:7302-14. [PMID: 19494152 DOI: 10.1523/jneurosci.3429-08.2009] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
One of the characteristics of animals in hibernation is reduced behavioral activity. The Caenorhabditis elegans dauer state is a hibernation-like state of diapause that displays a dramatic reduction in spontaneous locomotion. A similar dauer-like quiescent state is produced in adults by relatively strong mutations in the insulin/IGF-1 receptor homolog daf-2. In this study, we show that mutations affecting the neurotransmitter dopamine, which regulates voluntary movement in many organisms, can stimulate movement in dauers and dauer-like quiescent adults. Surprisingly, the movement of quiescent animals is stimulated by conditions that reduce dopamine signaling and also by conditions predicted to increase dopamine signaling. Reducing dopamine signaling is likely to stimulate movement by activating a foraging response also seen in nondauers after withdrawal of food. In contrast, the stimulation of movement by increased dopamine is much more pronounced in quiescent daf-2(-) dauer and dauer-like adult animals than in nondauaer animals. This altered response to dopamine is primarily attributable to activity of the FOXO (forkhead box O) transcription factor DAF-16 in neurons. We suggest that dauers and dauer-like quiescent adults may have underlying changes in the dopamine system that enable them to respond differently to environmental stimulation.
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46
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Taman A, Ribeiro P. Investigation of a dopamine receptor in Schistosoma mansoni: functional studies and immunolocalization. Mol Biochem Parasitol 2009; 168:24-33. [PMID: 19545592 DOI: 10.1016/j.molbiopara.2009.06.003] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2009] [Revised: 06/05/2009] [Accepted: 06/11/2009] [Indexed: 11/15/2022]
Abstract
A dopamine receptor (SmD2) was cloned from adult Schistosoma mansoni. The receptor has the classical heptahelical topology of class A (rhodopsin-like) G protein-coupled receptors (GPCR) and shares sequence homology with D2-like receptors from other species. The full length SmD2 cDNA was expressed in the yeast Saccharomyces cerevisiae and mammalian HEK293 cells. Functional assays in both expression systems revealed that SmD2 was responsive to dopamine in a dose-dependent manner, whereas other structurally related amines had no effect. Activation of SmD2 in mammalian cells caused an elevation in intracellular cAMP but not calcium, suggesting that the receptor coupled to Gs and the stimulation of adenylate cyclase. Pharmacological studies showed that the S. mansoni dopamine receptor was inhibited by apomorphine, a classical dopamine agonist, as well as known dopaminergic antagonists, including chlorpromazine, spiperone and haloperidol. SmD2 immunoreactivity was detected in membrane protein fractions of S. mansoni cercaria, in vitro transformed schistosomula and adult parasites, using a specific peptide antibody. When tested by confocal immunofluorescence, SmD2 was detected in the subtegumental somatic musculature and acetabulum of all larval stages tested. In the adults, SmD2 was enriched in the somatic muscles and, to a lesser extent, the muscular lining of the caecum. The results suggest that SmD2 is an important component of the neuromuscular system in schistosomes.
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Affiliation(s)
- Amira Taman
- Institute of Parasitology, McGill University, Macdonald Campus, 21,111 Lakeshore Road, Sainte Anne de Bellevue, Quebec, Canada
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47
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Anyanful A, Easley KA, Benian GM, Kalman D. Conditioning protects C. elegans from lethal effects of enteropathogenic E. coli by activating genes that regulate lifespan and innate immunity. Cell Host Microbe 2009; 5:450-62. [PMID: 19454349 DOI: 10.1016/j.chom.2009.04.012] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2008] [Revised: 12/18/2008] [Accepted: 04/06/2009] [Indexed: 01/15/2023]
Abstract
Caenorhabditis elegans exhibits avoidance behavior when presented with diverse bacterial pathogens. We hypothesized that exposure to pathogens might not only cause worms to move away but also simultaneously activate pathways that promote resistance to the pathogen. We show that brief exposure to virulent or avirulent strains of the bacterial pathogen enteropathogenic E. coli (EPEC) "immunizes"C. elegans to survive a subsequent exposure that would otherwise prove lethal, a phenomenon we refer to as "conditioning." Conditioning requires dopaminergic neurons; the p38 MAP kinase pathway, which regulates innate immunity; and the insulin/IGFR pathway, which regulates lifespan. Our findings suggest that the molecular pathways that control innate immunity and lifespan may be regulated or "conditioned" by exposure to pathogens to allow survival in noxious environments.
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Affiliation(s)
- Akwasi Anyanful
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, GA 30322, USA
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48
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Voglis G, Tavernarakis N. A synaptic DEG/ENaC ion channel mediates learning in C. elegans by facilitating dopamine signalling. EMBO J 2008; 27:3288-99. [PMID: 19037257 DOI: 10.1038/emboj.2008.252] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2008] [Accepted: 11/07/2008] [Indexed: 01/26/2023] Open
Abstract
An important component of learned behaviour is the ability to forecast positive or negative outcomes based on specific sensory cues. Predictive capacity is typically manifested by appropriate behavioural patterning. However, the molecular mechanisms underlying behavioural plasticity are poorly understood. Caenorhabditis elegans displays experience-dependent behavioural responses by associating distinct environmental signals. We find that ASIC-1, a member of the degenerin/epithelial sodium channel family, which localizes at presynaptic terminals of dopaminergic neurons, is required for associative learning in C. elegans. ASIC-1 functions in these neurons to amplify normal dopaminergic signalling, necessary for associative learning. Our results reveal a novel role of DEG/ENaC ion channels in neuronal communication by enhancing the activity of dopaminergic synapses. Similar mechanisms may facilitate synaptic plasticity in vertebrates.
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Affiliation(s)
- Giannis Voglis
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Heraklion, Crete, Greece
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Masler EP. Responses of Heterodera glycines and Meloidogyne incognita to exogenously applied neuromodulators. J Helminthol 2007; 81:421-7. [PMID: 18005465 DOI: 10.1017/s0022149x07850243] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Biogenic amines regulate important behaviours in nematodes and are associated with pharyngeal activity in plant-parasitic nematodes. A robust behavioural assay based upon nematode body movements was developed to expand the study of these and other neuroregulators in plant-parasitic nematodes. Dopamine, octopamine and serotonin each had significant but differing effects on the behaviour of soybean cyst nematode Heterodera glycines and root-knot nematode Meloidogyne incognita juveniles. Body movement frequency was increased twofold in H. glycines by 5 mM dopamine (P = 0.0001), but decreased by 50 mM dopamine in H. glycines (88%) and M. incognita (53%) (P < 0.0001). Movement frequency in both species was increased by 50-70% (P < 0.0001) by 50 mM octopamine, and 5 mM octopamine increased M. incognita movement frequency more than twofold (P < 0.0001). Movement frequency in each species was reduced by more than 90% by 5 mM serotonin (P < 0.0001). While amplitude of body movement in H. glycines was unaffected by any amine, it was significantly reduced in M. incognita by all amines (P < 0.0006). Stylet pulsing frequencies in either species were unaffected by dopamine or octopamine, but 5 mM serotonin stimulated pulsing in H. glycines by nearly 13-fold (P < 0.0001) and in M. incognita by more than 14-fold (P < 0.0001). The invertebrate neuropeptide FLRFamide (N-Phe-Leu-Arg-Phe) increased M. incognita body movement frequency 45% (P = 0.02) at 1 mM but did not affect stylet activity. Finally, H. glycines egg hatch was completely suppressed by 50 mM serotonin, and partially suppressed by 50 mM dopamine (75%; P < 0.0001) and 50 mM octopamine (55%; P < 0.0001).
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Affiliation(s)
- E P Masler
- Nematology Laboratory, US Department of Agriculture, Agricultural Research Service, Beltsville MD 20705, USA.
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50
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Schmidt E, Seifert M, Baumeister R. Caenorhabditis elegans as a model system for Parkinson's disease. NEURODEGENER DIS 2007; 4:199-217. [PMID: 17596715 DOI: 10.1159/000101845] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Parkinson's disease (PD) is one of the most common age-related neurodegenerative diseases that is characterized by selective loss of dopaminergic neurons. Despite recent findings from mammalian model systems, molecular mechanisms of the pathophysiology are poorly understood. Given the high conservation of molecular pathways from invertebrates to mammalians, combined with technical advantages, such as high-throughput approaches, Caenorhabditis elegans represents a powerful system for the identification of factors involved in neurodegeneration. In this review we describe that C. elegans can be used to advance our understanding of the genetic mechanisms implicated in these disorders.
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Affiliation(s)
- Enrico Schmidt
- Bioinformatics and Molecular Genetics (Faculty of Biology), Center for Biochemistry, University of Freiburg, Freiburg, Germany
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