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Poole RJ, Flames N, Cochella L. Neurogenesis in Caenorhabditis elegans. Genetics 2024:iyae116. [PMID: 39167071 DOI: 10.1093/genetics/iyae116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2024] [Accepted: 06/24/2024] [Indexed: 08/23/2024] Open
Abstract
Animals rely on their nervous systems to process sensory inputs, integrate these with internal signals, and produce behavioral outputs. This is enabled by the highly specialized morphologies and functions of neurons. Neuronal cells share multiple structural and physiological features, but they also come in a large diversity of types or classes that give the nervous system its broad range of functions and plasticity. This diversity, first recognized over a century ago, spurred classification efforts based on morphology, function, and molecular criteria. Caenorhabditis elegans, with its precisely mapped nervous system at the anatomical level, an extensive molecular description of most of its neurons, and its genetic amenability, has been a prime model for understanding how neurons develop and diversify at a mechanistic level. Here, we review the gene regulatory mechanisms driving neurogenesis and the diversification of neuron classes and subclasses in C. elegans. We discuss our current understanding of the specification of neuronal progenitors and their differentiation in terms of the transcription factors involved and ensuing changes in gene expression and chromatin landscape. The central theme that has emerged is that the identity of a neuron is defined by modules of gene batteries that are under control of parallel yet interconnected regulatory mechanisms. We focus on how, to achieve these terminal identities, cells integrate information along their developmental lineages. Moreover, we discuss how neurons are diversified postembryonically in a time-, genetic sex-, and activity-dependent manner. Finally, we discuss how the understanding of neuronal development can provide insights into the evolution of neuronal diversity.
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Affiliation(s)
- Richard J Poole
- Department of Cell and Developmental Biology, University College London, London WC1E 6BT, UK
| | - Nuria Flames
- Developmental Neurobiology Unit, Instituto de Biomedicina de Valencia IBV-CSIC, Valencia 46012, Spain
| | - Luisa Cochella
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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2
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Kim D, Nguyen TTM, Moon Y, Kim JM, Nam H, Cha DS, An YJ, de Guzman ACV, Park S. Time-Resolved Evaluation of L-Dopa Metabolism in Bacteria-Host Symbiotic System and the Effect on Parkinson's Molecular Pathology. SMALL METHODS 2024:e2400469. [PMID: 39058017 DOI: 10.1002/smtd.202400469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2024] [Indexed: 07/28/2024]
Abstract
The gut microbiome influences drug metabolism and therapeutic efficacy. Still, the lack of a general label-free approach for monitoring bacterial or host metabolic contribution hampers deeper insights. Here, a 2D nuclear magnetic resonance (NMR) approach is introduced that enables real-time monitoring of the metabolism of Levodopa (L-dopa), an anti-Parkinson drug, in both live bacteria and bacteria-host (Caenorhabditis elegans) symbiotic systems. The quantitative method reveals that discrete Enterococcus faecalis substrains produce different amounts of dopamine in live hosts, even though they are a single species and all have the Tyrosine decarboxylase (TyrDC) gene involved in L-dopa metabolism. The differential bacterial metabolic activity correlates with differing Parkinson's molecular pathology concerning alpha-synuclein aggregation as well as behavioral phenotypes. The gene's existence or expression is not an indicator of metabolic activity is also shown, underscoring the significance of quantitative metabolic estimation in vivo. This simple approach is widely adaptable to any chemical drug to elucidate pharmacomicrobiomic relationships and may help rapidly screen bacterial metabolic effects in drug development.
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Affiliation(s)
- Doyeon Kim
- Natural Products Research Institute, College of Pharmacy, Seoul National University, Seoul, 08826, South Korea
| | - Tin Tin Manh Nguyen
- Natural Products Research Institute, College of Pharmacy, Seoul National University, Seoul, 08826, South Korea
| | - Yechan Moon
- Natural Products Research Institute, College of Pharmacy, Seoul National University, Seoul, 08826, South Korea
| | - Jin-Mo Kim
- Natural Products Research Institute, College of Pharmacy, Seoul National University, Seoul, 08826, South Korea
| | - Hoonsik Nam
- Natural Products Research Institute, College of Pharmacy, Seoul National University, Seoul, 08826, South Korea
| | - Dong Seok Cha
- College of Pharmacy Woosuk University, Jeonbuk, 55338, South Korea
| | - Yong Jin An
- Natural Products Research Institute, College of Pharmacy, Seoul National University, Seoul, 08826, South Korea
| | - Arvie Camille V de Guzman
- Natural Products Research Institute, College of Pharmacy, Seoul National University, Seoul, 08826, South Korea
| | - Sunghyouk Park
- Natural Products Research Institute, College of Pharmacy, Seoul National University, Seoul, 08826, South Korea
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Yang Z, Zhang Z, Long X, Shi X, Wang D, Peng D, Ye S, Ding Z. Clarifying the Functional Role of Serotonin in Meloidogyne graminicola Host Plant Parasitism by Immunolocalization and RNA Interference. PHYTOPATHOLOGY 2024; 114:1401-1410. [PMID: 38148161 DOI: 10.1094/phyto-08-23-0290-r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2023]
Abstract
Serotonin (5-hydroxytryptamine) is an essential neurotransmitter involved in regulating various behaviors in plant-parasitic nematodes, including locomotion, egg laying, feeding, and mating. However, the functional role of serotonin in root-knot nematode invasion of host plants and the molecular mechanisms underlying feeding behavior remain poorly understood. In this study, we tested the effects of exogenous serotonin and the pharmacological compounds fluoxetine and methiothepin on the feeding behaviors of Meloidogyne graminicola. Our results suggested that M. graminicola possesses an endogenous serotonin signaling pathway and that serotonin plays a crucial role in modulating feeding behaviors in M. graminicola second-stage juveniles. We also identified and cloned the serotonin synthesis enzyme tryptophan hydroxylase (Mg-tph-1) in M. graminicola and investigated the role of endogenous serotonin by generating RNA interference nematodes in Mg-tph-1. Silencing Mg-tph-1 substantially reduced nematode invasion, development, and reproduction. According to the immunostaining results, we speculated that these serotonin immunoreactive cells near the nerve ring in M. graminicola are likely homologous to Caenorhabditis elegans ADFs, NSMs, and RIH serotonergic neurons. Furthermore, we investigated the impact of phytoserotonin on nematode invasion and development in rice by overexpressing OsTDC-3 or supplementing rice plants with tryptamine and found that an increase in phytoserotonin increases nematode pathogenicity. Overall, our study provides insights into the essential role of serotonin in M. graminicola host plant parasitism and proposes that the serotonergic signaling pathway could be a potential target for controlling plant-parasitic nematodes.
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Affiliation(s)
- Zhuhong Yang
- College of Plant Protection, Hunan Agricultural University, Changsha 410128, P.R. China
- Hunan Provincial Engineering and Technology Research Center for Biopesticide and Formulation Processing, Changsha 410128, P.R. China
| | - Zixu Zhang
- College of Plant Protection, Hunan Agricultural University, Changsha 410128, P.R. China
| | - Xiping Long
- College of Plant Protection, Hunan Agricultural University, Changsha 410128, P.R. China
| | - Xuqi Shi
- College of Plant Protection, Hunan Agricultural University, Changsha 410128, P.R. China
| | - Di Wang
- College of Plant Protection, Hunan Agricultural University, Changsha 410128, P.R. China
| | - Deliang Peng
- State Key Laboratory for Biology of Plant Diseases and Insect Pests/Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, P.R. China
| | - Shan Ye
- College of Plant Protection, Hunan Agricultural University, Changsha 410128, P.R. China
- Hunan Provincial Engineering and Technology Research Center for Biopesticide and Formulation Processing, Changsha 410128, P.R. China
| | - Zhong Ding
- College of Plant Protection, Hunan Agricultural University, Changsha 410128, P.R. China
- Hunan Provincial Engineering and Technology Research Center for Biopesticide and Formulation Processing, Changsha 410128, P.R. China
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Ebert MS, Bargmann CI. Evolution remodels olfactory and mating-receptive behaviors in the transition from female to hermaphrodite reproduction. Curr Biol 2024; 34:969-979.e4. [PMID: 38340714 DOI: 10.1016/j.cub.2024.01.050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Revised: 12/20/2023] [Accepted: 01/19/2024] [Indexed: 02/12/2024]
Abstract
Male/hermaphrodite species have arisen multiple times from a male/female ancestral state in nematodes, providing a model to study behavioral adaptations to different reproductive strategies. Here, we examined the mating behaviors of male/female (gonochoristic) Caenorhabditis species in comparison with male/hermaphrodite (androdiecious) close relatives. We find that females from two species in the Elegans group chemotax to volatile odor from males, but hermaphrodites do not. Females, but not hermaphrodites, also display known mating-receptive behaviors such as sedation when male reproductive structures contact the vulva. Focusing on the male/female species C. nigoni, we show that female chemotaxis to males is limited to adult females approaching adult or near-adult males and relies upon the AWA neuron-specific transcription factor ODR-7, as does male chemotaxis to female odor as previously shown in C. elegans. However, female receptivity during mating contact is odr-7 independent. All C. nigoni female behaviors are suppressed by mating and all are absent in young hermaphrodites from the sister species C. briggsae. However, latent receptivity during mating contact can be uncovered in mutant or aged C. briggsae hermaphrodites that lack self-sperm. These results reveal two mechanistically distinct components of the shift from female to hermaphrodite behavior: the loss of female-specific odr-7-dependent chemotaxis and a sperm-dependent state of reduced receptivity to mating contact. Hermaphrodites from a second androdioecious species, C. tropicalis, recover all female behaviors upon aging, including chemotaxis to males. Regaining mating receptivity after sperm depletion could maximize hermaphrodite fitness across their lifespan.
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Affiliation(s)
- Margaret S Ebert
- The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
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Salgueiro WG, Soares MV, Martins CF, Paula FR, Rios-Anjos RM, Carrazoni T, Mori MA, Müller RU, Aschner M, Dal Belo CA, Ávila DS. Dopaminergic modulation by quercetin: In silico and in vivo evidence using Caenorhabditis elegans as a model. Chem Biol Interact 2023; 382:110610. [PMID: 37348670 PMCID: PMC10527449 DOI: 10.1016/j.cbi.2023.110610] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2022] [Revised: 06/12/2023] [Accepted: 06/19/2023] [Indexed: 06/24/2023]
Abstract
Quercetin is a flavonol widely distributed in plants and has various described biological functions. Several studies have reported on its ability to restore neuronal function in a wide variety of disease models, including animal models of neurodegenerative disorders such as Parkinson's disease. Quercetin per se can act as a neuroprotector/neuromodulator, especially in diseases related to impaired dopaminergic neurotransmission. However, little is known about how quercetin interacts with the dopaminergic machinery. Here we employed the nematode Caenorhabditis elegans to study this putative interaction. After observing behavioral modulation, mutant analysis and gene expression in C. elegans upon exposure to quercetin at a concentration that does not protect against MPTP, we constructed a homology-based dopamine transporter protein model to conduct a docking study. This led to suggestive evidence on how quercetin may act as a dopaminergic modulator by interacting with C. elegans' dopamine transporter and alter the nematode's exploratory behavior. Consistent with this model, quercetin controls C. elegans behavior in a way dependent on the presence of both the dopamine transporter (dat-1), which is up-regulated upon quercetin exposure, and the dopamine receptor 2 (dop-2), which appears to be mandatory for dat-1 up-regulation. Our data propose an interaction with the dopaminergic machinery that may help to establish the effects of quercetin as a neuromodulator.
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Affiliation(s)
- Willian Goulart Salgueiro
- Research Group in Biochemistry and Toxicology in Caenorhabditis elegans (GBToxCe), Federal University of Pampa - UNIPAMPA, CEP 97500-970, Uruguaiana, RS, Brazil; Department of Biochemistry and Tissue Biology, University of Campinas, Monteiro Lobato Avenue, 255, Campinas, São Paulo, 13083-862, Brazil; Cologne Excellence Cluster on Cellular Stress Responses in Aging-associated Diseases (CECAD), University of Cologne, Cologne, 50931, Germany; Department II of Internal Medicine and Center for Molecular Medicine Cologne, University of Cologne, Cologne, Germany
| | - Marcell Valandro Soares
- Research Group in Biochemistry and Toxicology in Caenorhabditis elegans (GBToxCe), Federal University of Pampa - UNIPAMPA, CEP 97500-970, Uruguaiana, RS, Brazil; Department of Biochemistry and Molecular Biology, Post-graduate Program in Biological Sciences, Federal University of Santa Maria, Camobi, 97105-900, Santa Maria, RS, Brazil
| | - Cassiano Fiad Martins
- Research Group in Biochemistry and Toxicology in Caenorhabditis elegans (GBToxCe), Federal University of Pampa - UNIPAMPA, CEP 97500-970, Uruguaiana, RS, Brazil
| | - Fávero Reisdorfer Paula
- Laboratory for Development and Quality Control in Medicines (LDCQ), Federal University of Pampa, Uruguaiana, RS, Brazil
| | | | - Thiago Carrazoni
- Neurobiology and Toxinology Laboratory, (LANETOX), Federal University of Pampa - UNIPAMPA, CEP 97300-000, São Gabriel, RS, Brazil
| | - Marcelo A Mori
- Department of Biochemistry and Tissue Biology, University of Campinas, Monteiro Lobato Avenue, 255, Campinas, São Paulo, 13083-862, Brazil; Obesity and Comorbidities Research Center (OCRC), University of Campinas, Campinas, SP, Brazil; Experimental Medicine Research Cluster, University of Campinas, Campinas, SP, Brazil
| | - Roman-Ulrich Müller
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-associated Diseases (CECAD), University of Cologne, Cologne, 50931, Germany; Department II of Internal Medicine and Center for Molecular Medicine Cologne, University of Cologne, Cologne, Germany
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY, 10461, USA
| | - Cháriston André Dal Belo
- Department of Biochemistry and Molecular Biology, Post-graduate Program in Biological Sciences, Federal University of Santa Maria, Camobi, 97105-900, Santa Maria, RS, Brazil; Neurobiology and Toxinology Laboratory, (LANETOX), Federal University of Pampa - UNIPAMPA, CEP 97300-000, São Gabriel, RS, Brazil; Multidisciplinar Department, Federal University of São Paulo (UNIFESP), Angelica Street, 100- CEP 06110295, Osasco, SP, Brazil
| | - Daiana Silva Ávila
- Research Group in Biochemistry and Toxicology in Caenorhabditis elegans (GBToxCe), Federal University of Pampa - UNIPAMPA, CEP 97500-970, Uruguaiana, RS, Brazil; Department of Biochemistry and Molecular Biology, Post-graduate Program in Biological Sciences, Federal University of Santa Maria, Camobi, 97105-900, Santa Maria, RS, Brazil.
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6
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Starr LA, McKay LE, Peter KN, Seyfarth LM, Berkowitz LA, Caldwell KA, Caldwell GA. Attenuation of Dopaminergic Neurodegeneration in a C. elegans Parkinson's Model through Regulation of Xanthine Dehydrogenase (XDH-1) Expression by the RNA Editase, ADR-2. J Dev Biol 2023; 11:jdb11020020. [PMID: 37218814 DOI: 10.3390/jdb11020020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2023] [Revised: 05/16/2023] [Accepted: 05/18/2023] [Indexed: 05/24/2023] Open
Abstract
Differential RNA editing by adenosine deaminases that act on RNA (ADARs) has been implicated in several neurological disorders, including Parkinson's disease (PD). Here, we report results of a RNAi screen of genes differentially regulated in adr-2 mutants, normally encoding the only catalytically active ADAR in Caenorhabditis elegans, ADR-2. Subsequent analysis of candidate genes that alter the misfolding of human α-synuclein (α-syn) and dopaminergic neurodegeneration, two PD pathologies, reveal that reduced expression of xdh-1, the ortholog of human xanthine dehydrogenase (XDH), is protective against α-synuclein-induced dopaminergic neurodegeneration. Further, RNAi experiments show that WHT-2, the worm ortholog of the human ABCG2 transporter and a predicted interactor of XDH-1, is the rate-limiting factor in the ADR-2, XDH-1, WHT-2 system for dopaminergic neuroprotection. In silico structural modeling of WHT-2 indicates that the editing of one nucleotide in the wht-2 mRNA leads to the substitution of threonine with alanine at residue 124 in the WHT-2 protein, changing hydrogen bonds in this region. Thus, we propose a model where wht-2 is edited by ADR-2, which promotes optimal export of uric acid, a known substrate of WHT-2 and a product of XDH-1 activity. In the absence of editing, uric acid export is limited, provoking a reduction in xdh-1 transcription to limit uric acid production and maintain cellular homeostasis. As a result, elevation of uric acid is protective against dopaminergic neuronal cell death. In turn, increased levels of uric acid are associated with a decrease in ROS production. Further, downregulation of xdh-1 is protective against PD pathologies because decreased levels of XDH-1 correlate to a concomitant reduction in xanthine oxidase (XO), the form of the protein whose by-product is superoxide anion. These data indicate that modifying specific targets of RNA editing may represent a promising therapeutic strategy for PD.
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Affiliation(s)
- Lindsey A Starr
- Department of Biological Sciences, Center for Convergent Biomedicine, Alabama Life Research Institute, The University of Alabama, Tuscaloosa, AL 35487, USA
| | - Luke E McKay
- Department of Biological Sciences, Center for Convergent Biomedicine, Alabama Life Research Institute, The University of Alabama, Tuscaloosa, AL 35487, USA
| | - Kylie N Peter
- Department of Biological Sciences, Center for Convergent Biomedicine, Alabama Life Research Institute, The University of Alabama, Tuscaloosa, AL 35487, USA
| | - Lena M Seyfarth
- Department of Biological Sciences, Center for Convergent Biomedicine, Alabama Life Research Institute, The University of Alabama, Tuscaloosa, AL 35487, USA
| | - Laura A Berkowitz
- Department of Biological Sciences, Center for Convergent Biomedicine, Alabama Life Research Institute, The University of Alabama, Tuscaloosa, AL 35487, USA
| | - Kim A Caldwell
- Department of Biological Sciences, Center for Convergent Biomedicine, Alabama Life Research Institute, The University of Alabama, Tuscaloosa, AL 35487, USA
- Department of Neurology, Center for Neurodegeneration and Experimental Therapeutics, Nathan Shock Center of Excellence for the Basic Biology of Aging, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Guy A Caldwell
- Department of Biological Sciences, Center for Convergent Biomedicine, Alabama Life Research Institute, The University of Alabama, Tuscaloosa, AL 35487, USA
- Department of Neurology, Center for Neurodegeneration and Experimental Therapeutics, Nathan Shock Center of Excellence for the Basic Biology of Aging, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
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7
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Parrales-Macias V, Michel PP, Tourville A, Raisman-Vozari R, Haïk S, Hunot S, Bizat N, Lannuzel A. The Pesticide Chlordecone Promotes Parkinsonism-like Neurodegeneration with Tau Lesions in Midbrain Cultures and C. elegans Worms. Cells 2023; 12:cells12091336. [PMID: 37174736 PMCID: PMC10177284 DOI: 10.3390/cells12091336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 04/10/2023] [Accepted: 05/05/2023] [Indexed: 05/15/2023] Open
Abstract
Chlordecone (CLD) is an organochlorine pesticide (OCP) that is currently banned but still contaminates ecosystems in the French Caribbean. Because OCPs are known to increase the risk of Parkinson's disease (PD), we tested whether chronic low-level intoxication with CLD could reproduce certain key characteristics of Parkinsonism-like neurodegeneration. For that, we used culture systems of mouse midbrain dopamine (DA) neurons and glial cells, together with the nematode C. elegans as an in vivo model organism. We established that CLD kills cultured DA neurons in a concentration- and time-dependent manner while exerting no direct proinflammatory effects on glial cells. DA cell loss was not impacted by the degree of maturation of the culture. The use of fluorogenic probes revealed that CLD neurotoxicity was the consequence of oxidative stress-mediated insults and mitochondrial disturbances. In C. elegans worms, CLD exposure caused a progressive loss of DA neurons associated with locomotor deficits secondary to alterations in food perception. L-DOPA, a molecule used for PD treatment, corrected these deficits. Cholinergic and serotoninergic neuronal cells were also affected by CLD in C. elegans, although to a lesser extent than DA neurons. Noticeably, CLD also promoted the phosphorylation of the aggregation-prone protein tau (but not of α-synuclein) both in midbrain cell cultures and in a transgenic C. elegans strain expressing a human form of tau in neurons. In summary, our data suggest that CLD is more likely to promote atypical forms of Parkinsonism characterized by tau pathology than classical synucleinopathy-associated PD.
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Affiliation(s)
- Valeria Parrales-Macias
- Paris Brain Institute-ICM, Inserm, CNRS, Hôpital de la Pitié Salpêtrière, Sorbonne Université, 75013 Paris, France
| | - Patrick P Michel
- Paris Brain Institute-ICM, Inserm, CNRS, Hôpital de la Pitié Salpêtrière, Sorbonne Université, 75013 Paris, France
| | - Aurore Tourville
- Paris Brain Institute-ICM, Inserm, CNRS, Hôpital de la Pitié Salpêtrière, Sorbonne Université, 75013 Paris, France
| | - Rita Raisman-Vozari
- Paris Brain Institute-ICM, Inserm, CNRS, Hôpital de la Pitié Salpêtrière, Sorbonne Université, 75013 Paris, France
| | - Stéphane Haïk
- Paris Brain Institute-ICM, Inserm, CNRS, Hôpital de la Pitié Salpêtrière, Sorbonne Université, 75013 Paris, France
| | - Stéphane Hunot
- Paris Brain Institute-ICM, Inserm, CNRS, Hôpital de la Pitié Salpêtrière, Sorbonne Université, 75013 Paris, France
| | - Nicolas Bizat
- Paris Brain Institute-ICM, Inserm, CNRS, Hôpital de la Pitié Salpêtrière, Sorbonne Université, 75013 Paris, France
- Faculté de Pharmacie de Paris, Université de Paris Cité, 75006 Paris, France
| | - Annie Lannuzel
- Paris Brain Institute-ICM, Inserm, CNRS, Hôpital de la Pitié Salpêtrière, Sorbonne Université, 75013 Paris, France
- Centre Hospitalier Universitaire de la Guadeloupe, Service de Neurologie, Faculté de Médecine de l'Université des Antilles, Centre d'Investigation Clinique (CIC) 1424, 97159 Pointe-à-Pitre, France
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8
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Chen P, Cheng H, Zheng F, Li S, Bornhorst J, Yang B, Lee KH, Ke T, Li Y, Schwerdtle T, Yang X, Bowman AB, Aschner M. BTBD9 attenuates manganese-induced oxidative stress and neurotoxicity by regulating insulin growth factor signaling pathway. Hum Mol Genet 2022; 31:2207-2222. [PMID: 35134179 PMCID: PMC9262395 DOI: 10.1093/hmg/ddac025] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 12/29/2021] [Accepted: 01/21/2022] [Indexed: 02/05/2023] Open
Abstract
Manganese (Mn) is an essential mineral, but excess exposure can cause dopaminergic neurotoxicity. Restless legs syndrome (RLS) is a common neurological disorder, but the etiology and pathology remain largely unknown. The purpose of this study was to identify the role of Mn in the regulation of an RLS genetic risk factor BTBD9, characterize the function of BTBD9 in Mn-induced oxidative stress and dopaminergic neuronal dysfunction. We found that human subjects with high blood Mn levels were associated with decreased BTBD9 mRNA levels, when compared with subjects with low blood Mn levels. In A549 cells, Mn exposure decreased BTBD9 protein levels. In Caenorhabditis elegans, loss of hpo-9 (BTBD9 homolog) resulted in more susceptibility to Mn-induced oxidative stress and mitochondrial dysfunction, as well as decreased dopamine levels and alternations of dopaminergic neuronal morphology and behavior. Overexpression of hpo-9 in mutant animals restored these defects and the protection was eliminated by mutation of the forkhead box O (FOXO). In addition, expression of hpo-9 upregulated FOXO protein levels and decreased protein kinase B levels. These results suggest that elevated Mn exposure might be an environmental risk factor for RLS. Furthermore, BTBD9 functions to alleviate Mn-induced oxidative stress and neurotoxicity via regulation of insulin/insulin-like growth factor signaling pathway.
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Affiliation(s)
- Pan Chen
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Hong Cheng
- Department of Occupational Health and Environmental Health, School of Public Health, Guangxi Medical University, Nanning 53021, China
| | - Fuli Zheng
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Shaojun Li
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
- Department of Occupational Health and Environmental Health, School of Public Health, Guangxi Medical University, Nanning 53021, China
| | - Julia Bornhorst
- Food Chemistry, Faculty of Mathematics and Natural Sciences, University of Wuppertal, Wuppertal 42119, Germany
| | - Bobo Yang
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Kun He Lee
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Tao Ke
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Yunhui Li
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
- Key Laboratory of Environmental Medicine Engineering Ministry of Education, School of Public Health, Southeast University, Nanjing, Jiangsu 210000, China
| | - Tanja Schwerdtle
- Department of Food Chemistry, Institute of Nutritional Science, University of Potsdam, Nuthetal 14558, Germany
- TraceAge—DFG Research Group on Interactions of Essential Trace Elements in Healthy and Diseased Elderly (FOR 2558), Berlin-Potsdam-Jena 14558, Germany
| | - Xiaobo Yang
- Department of Occupational Health and Environmental Health, School of Public Health, Guangxi Medical University, Nanning 53021, China
- Department of Public Health, School of Medicine, Guangxi University of Science and Technology, Liuzhou 545026, China
| | - Aaron B Bowman
- School of Health Sciences, Purdue University, West Lafayette, IN 47907, USA
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
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9
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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] [MESH Headings] [Grants] [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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10
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Ijomone OM, Gubert P, Okoh COA, Varão AM, Amara LDO, Aluko OM, Aschner M. Application of Fluorescence Microscopy and Behavioral Assays to Demonstrating Neuronal Connectomes and Neurotransmitter Systems in C. elegans. NEUROMETHODS 2021; 172:399-426. [PMID: 34754139 PMCID: PMC8575032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The nematode Caenorhabditis elegans (C. elegans) is a prevailing model which is commonly utilized in a variety of biomedical research arenas, including neuroscience. Due to its transparency and simplicity, it is becoming a choice model organism for conducting imaging and behavioral assessment crucial to understanding the intricacies of the nervous system. Here, the methods required for neuronal characterization using fluorescent proteins and behavioral tasks are described. These are simplified protocols using fluorescent microscopy and behavioral assays to examine neuronal connections and associated neurotransmitter systems involved in normal physiology and aberrant pathology of the nervous system. Our aim is to make available to readers some streamlined and replicable procedures using C. elegans models as well as highlighting some of the limitations.
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Affiliation(s)
- Omamuyovwi M. Ijomone
- The Neuro- Lab, School of Health and Health Technology, Federal University of Technology, Akure, Nigeria
- Department of Human Anatomy, School of Health and Health Technology, Federal University of Technology, Akure, Nigeria
| | - Priscila Gubert
- Department of Biochemistry, Laboratório de Imunopatologia Keizo Asami, LIKA, Federal University of Pernambuco, Recife, Brazil
- Postgraduate Program in Pure and Applied Chemistry, Federal University of Western of Bahia, Bahia, Brazil
| | - Comfort O. A. Okoh
- The Neuro- Lab, School of Health and Health Technology, Federal University of Technology, Akure, Nigeria
| | - Alexandre M. Varão
- Postgraduate Program in Pure and Applied Chemistry, Federal University of Western of Bahia, Bahia, Brazil
| | - Leandro de O. Amara
- Postgraduate Program in Pure and Applied Chemistry, Federal University of Western of Bahia, Bahia, Brazil
| | - Oritoke M. Aluko
- The Neuro- Lab, School of Health and Health Technology, Federal University of Technology, Akure, Nigeria
- Department of Physiology, School of Health and Health Technology, Federal University of Technology, Akure, Nigeria
| | - Michael Aschner
- Departments of Molecular Pharmacology and Neurosciences, Albert Einstein College of Medicine, NY, USA
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11
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Abstract
Mechanosensation such as touch, hearing and proprioception, is functionally regulated by mechano-gated ion channels through the process of transduction. Mechano-gated channels are a subtype of gated ion channels engaged in converting mechanical stimuli to chemical or electrical signals thereby modulating sensation. To date, a few families of mechano-gated channels (DEG/ENaC, TRPN, K2P, TMC and Piezo) have been identified in eukaryotes. Using a tractable genetic model organism Caenorhabditis elegans, the molecular mechanism of mechanosensation have been the focus of much research to comprehend the process of mechanotransduction. Comprising of almost all metazoans classes of ion channels, transporters and receptors, C. elegans is a powerful genetic model to explore mechanosensitive behaviors such as touch sensation and proprioception. The nematode relies primarily on its sensory abilities to survive in its natural environment. Genetic screening, calcium imaging and electrophysiological analysis have established that ENaC proteins and TRPN channel (TRP-4 protein) can characterize mechano-gated channels in C. elegans. A recent study reported that TMCs are likely the pore-forming subunit of a mechano-gated channel in C. elegans. Nevertheless, it still remains unclear whether Piezo as well as other candidate proteins can form mechano-gated channels in C. elegans.
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Affiliation(s)
- Umar Al-Sheikh
- Department of Neurobiology and Department of Neurosurgery of the First Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang, China.,NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Zhejiang, China
| | - Lijun Kang
- Department of Neurobiology and Department of Neurosurgery of the First Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang, China.,NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Zhejiang, China
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12
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Fueser H, Mueller MT, Traunspurger W. Rapid ingestion and egestion of spherical microplastics by bacteria-feeding nematodes. CHEMOSPHERE 2020; 261:128162. [PMID: 33113662 DOI: 10.1016/j.chemosphere.2020.128162] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 08/13/2020] [Accepted: 08/17/2020] [Indexed: 06/11/2023]
Abstract
Microplastics, anthropogenically released into freshwaters, settle in sediments, where they are directly ingested by benthic organisms. However, to the best of our knowledge, fine-scale studies of microplastic ingestion and egestion by nematodes, one of the most abundant meiofaunal taxa, are lacking. We therefore conducted a time series of the ingestion and egestion by adult Caenorhabditis elegans and Pristionchus pacificus of 0.5- and 1.0-μm fluorescent polystyrene (PS) beads along with bacteria. The nematodes were exposed to 107 beads ml-1 in aqueous medium for 5 min-24 h and pumping rates of C. elegans were determined. In the egestion study, PS bead egestion was monitored in nematodes with high microplastic body burdens for 5 min-24 h in microplastic-free medium. Ingested beads were detected already within 5 min and up to 203 ± 15 PS beads (1.0 μm; C. elegans) were found after 30 min. Overall, significantly more 1.0-μm than 0.5-μm PS beads were taken up. The distinct feeding behaviors of the two species influenced their PS bead body burdens. Ingested PS beads were almost completely egested within the first 20-40 min in the presence of sufficient food. In C. elegans, 1.0-μm beads were egested less rapidly than 0.5-μm PS beads. Given the rapid ingestion and egestion of the beads, our study demonstrates that the actual amount of ingested and egested microplastics by nematodes in the environment may be several times higher than the microplastic body burdens may imply. However, spherical PS beads did not bioconcentrate in nematodes.
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Affiliation(s)
- Hendrik Fueser
- Bielefeld University, Animal Ecology, Konsequenz 45, 33615, Bielefeld, Germany.
| | | | - Walter Traunspurger
- Bielefeld University, Animal Ecology, Konsequenz 45, 33615, Bielefeld, Germany
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13
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Manalo RVM, Medina PMB. Caffeine reduces deficits in mechanosensation and locomotion induced by L-DOPA and protects dopaminergic neurons in a transgenic Caenorhabditis elegans model of Parkinson's disease. PHARMACEUTICAL BIOLOGY 2020; 58:721-731. [PMID: 32715838 PMCID: PMC7470077 DOI: 10.1080/13880209.2020.1791192] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 05/02/2020] [Accepted: 06/30/2020] [Indexed: 05/08/2023]
Abstract
CONTEXT L-DOPA is the first-line drug for Parkinson's disease (PD). However, chronic use can lead to dyskinesia. Caffeine, which is a known neuroprotectant, can potentially act as an adjunct to minimise adverse effects of L-DOPA. OBJECTIVES This study determined changes in terms of neurodegeneration, locomotion and mechanosensation in Caenorhabditis elegans (Rhabditidae) strain UA57 overexpressing tyrosine hydroxylase (CAT-2) when treated with caffeine, L-DOPA or their combinations. MATERIALS AND METHODS Neurodegeneration was monitored via fluorescence microscopy of GFP-tagged dopaminergic neurons in the head and tail regions of C. elegans (n = 20). Meanwhile, mechanosensation and locomotion under vehicle (0.1% DMSO), L-DOPA (60 mM), caffeine (10 mM) or 60 mM L-DOPA + 10 or 20 mM caffeine (60LC10 and 60LC20) treatments were scored for 3 days. RESULTS L-DOPA (60 mM) reduced CEP and ADE neurons by 4.3% on day 3, with a concomitant decrease in fluorescence by 44.6%. This correlated with reductions in gentle head (-35%) and nose touch (-40%) responses, but improved locomotion (20-75%) compared with vehicle alone. CEP and ADE neuron counts were preserved with caffeine (10 mM) or 60LC10 (98-100%), which correlated with improved mechanosensation (10-23%) and locomotion (18-76%). However, none of the treatments was able to preserve PDE neuron count, reducing the basal slowing response. Discussion and conclusions: Taken together, we show that caffeine can protect DAergic neurons and can reduce aberrant locomotion and loss of sensation when co-administered with L-DOPA, which can potentially impact PD treatment and warrants further investigation.
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Affiliation(s)
- Rafael Vincent M. Manalo
- Biological Models Laboratory, Department of Biochemistry and Molecular Biology, College of Medicine, University of the Philippines Manila, Manila, Philippines
| | - Paul Mark B. Medina
- Biological Models Laboratory, Department of Biochemistry and Molecular Biology, College of Medicine, University of the Philippines Manila, Manila, Philippines
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14
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Miller MW. Dopamine as a Multifunctional Neurotransmitter in Gastropod Molluscs: An Evolutionary Hypothesis. THE BIOLOGICAL BULLETIN 2020; 239:189-208. [PMID: 33347799 PMCID: PMC8016498 DOI: 10.1086/711293] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
AbstractThe catecholamine 3,4-dihydroxyphenethylamine, or dopamine, acts as a neurotransmitter across a broad phylogenetic spectrum. Functions attributed to dopamine in the mammalian brain include regulation of motor circuits, valuation of sensory stimuli, and mediation of reward or reinforcement signals. Considerable evidence also supports a neurotransmitter role for dopamine in gastropod molluscs, and there is growing appreciation for its potential common functions across phylogeny. This article reviews evidence for dopamine's transmitter role in the nervous systems of gastropods. The functional properties of identified dopaminergic neurons in well-characterized neural circuits suggest a hypothetical incremental sequence by which dopamine accumulated its diverse roles. The successive acquisition of dopamine functions is proposed in the context of gastropod feeding behavior: (1) sensation of potential nutrients, (2) activation of motor circuits, (3) selection of motor patterns from multifunctional circuits, (4) valuation of sensory stimuli with reference to internal state, (5) association of motor programs with their outcomes, and (6) coincidence detection between sensory stimuli and their consequences. At each stage of this sequence, it is proposed that existing functions of dopaminergic neurons favored their recruitment to fulfill additional information processing demands. Common functions of dopamine in other intensively studied groups, ranging from mammals and insects to nematodes, suggest an ancient origin for this progression.
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15
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Alcedo J, Prahlad V. Neuromodulators: an essential part of survival. J Neurogenet 2020; 34:475-481. [PMID: 33170042 PMCID: PMC7811185 DOI: 10.1080/01677063.2020.1839066] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Accepted: 10/15/2020] [Indexed: 10/23/2022]
Abstract
The coordination between the animal's external environment and internal state requires constant modulation by chemicals known as neuromodulators. Neuromodulators, such as biogenic amines, neuropeptides and cytokines, promote organismal homeostasis. Over the past several decades, Caenorhabditiselegans has grown into a powerful model organism that allows the elucidation of the mechanisms of action of neuromodulators that are conserved across species. In this perspective, we highlight a collection of articles in this issue that describe how neuromodulators optimize C. elegans survival.
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Affiliation(s)
- Joy Alcedo
- Department of Biological Sciences, Wayne State University, Detroit, MI, USA
| | - Veena Prahlad
- Department of Biology, Aging Mind and Brain Initiative, and Iowa Neuroscience Institute, University of Iowa, Iowa City, IA, USA
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16
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Abstract
The serotonergic modulation of feeding behaviour has been intensively studied in several invertebrate groups, including Arthropoda, Annelida, Nematoda and Mollusca. These studies offer comparative information on feeding regulation across divergent phyla and also provide general insights into the neural control of feeding. Specifically, model invertebrates are ideal for parsing feeding behaviour into component parts and examining the underlying mechanisms at the levels of biochemical pathways, single cells and identified neural circuitry. Research has found that serotonin is crucial during certain phases of feeding behaviour, especially movements directly underlying food intake, but inessential during other phases. In addition, while the serotonin system can be manipulated systemically in many animals, invertebrate model organisms also allow manipulations at the level of single cells and molecules, revealing limited and precise serotonergic actions. The latter highlight the importance of local versus global modulatory effects of serotonin, a potentially significant consideration for drug and pesticide design.
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Affiliation(s)
- Ann Jane Tierney
- Neuroscience Program, Psychological and Brain Sciences, Colgate University, Hamilton, NY, USA
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17
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Barrière A, Bertrand V. Neuronal specification in C. elegans: combining lineage inheritance with intercellular signaling. J Neurogenet 2020; 34:273-281. [PMID: 32603241 DOI: 10.1080/01677063.2020.1781850] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The nervous system is composed of a high diversity of neuronal types. How this diversity is generated during development is a key question in neurobiology. Addressing this question is one of the reasons that led Sydney Brenner to develop the nematode C. elegans as a model organism. While there was initially a debate on whether the neuronal specification follows a 'European' model (determined by ancestry) or an 'American' model (determined by intercellular communication), several decades of research have established that the truth lies somewhere in between. Neurons are specified by the combination of transcription factors inherited from the ancestor cells and signaling between neighboring cells (especially Wnt and Notch signaling). This converges to the activation in newly generated postmitotic neurons of a specific set of terminal selector transcription factors that initiate and maintain the differentiation of the neuron. In this review, we also discuss the evolution of these specification mechanisms in other nematodes and beyond.
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Affiliation(s)
- Antoine Barrière
- Aix Marseille University, CNRS, IBDM, Turing Center for Living Systems, Marseille, France
| | - Vincent Bertrand
- Aix Marseille University, CNRS, IBDM, Turing Center for Living Systems, Marseille, France
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18
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Ishita Y, Chihara T, Okumura M. Serotonergic modulation of feeding behavior in Caenorhabditis elegans and other related nematodes. Neurosci Res 2020; 154:9-19. [DOI: 10.1016/j.neures.2019.04.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Revised: 04/10/2019] [Accepted: 04/22/2019] [Indexed: 10/26/2022]
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19
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Cruz-Corchado J, Ooi FK, Das S, Prahlad V. Global Transcriptome Changes That Accompany Alterations in Serotonin Levels in Caenorhabditis elegans. G3 (BETHESDA, MD.) 2020; 10:1225-1246. [PMID: 31996358 PMCID: PMC7144078 DOI: 10.1534/g3.120.401088] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 01/25/2020] [Indexed: 11/18/2022]
Abstract
Serotonin (5-hydroxytryptamine, 5-HT), is a phylogenetically ancient molecule best characterized as a neurotransmitter that modulates multiple aspects of mood and social cognition. The roles that 5-HT plays in normal and abnormal behavior are not fully understood but have been posited to be due to its common function as a 'defense signal'. However, 5-HT levels also systemically impact cell physiology, modulating cell division, migration, apoptosis, mitochondrial biogenesis, cellular metabolism and differentiation. Whether these diverse cellular effects of 5-HT also share a common basis is unclear. C. elegans provides an ideal system to interrogate the systemic effects of 5-HT, since lacking a blood-brain barrier, 5-HT synthesized and released by neurons permeates the organism to modulate neuronal as well as non-neuronal cells throughout the body. Here we used RNA-Seq to characterize the systemic changes in gene expression that occur in C. elegans upon altering 5-HT levels, and compared the transcriptomes to published datasets. We find that an acute increase in 5-HT is accompanied by a global decrease in gene expression levels, upregulation of genes involved in stress pathways, changes that significantly correlate with the published transcriptomes of animals that have activated defense and immune responses, and an increase in levels of phosphorylated eukaryotic initiation factor, eIF2α. In 5-HT deficient animals lacking tryptophan hydroxylase (tph-1(mg280)II) there is a net increase in gene expression, with an overrepresentation of genes related to development and chromatin. Surprisingly, the transcriptomes of animals with acute increases in 5-HT levels, and 5-HT deficiency do not overlap with transcriptomes of mutants with whom they share striking physiological resemblance. These studies are the first to catalog systemic transcriptome changes that occur upon alterations in 5-HT levels. They further show that in C. elegans changes in gene expression upon altering 5-HT levels, and changes in physiology, are not directly correlated.
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Affiliation(s)
- Johnny Cruz-Corchado
- Department of Biology, Aging Mind and Brain Initiative, Iowa Neuroscience Institute, 143 Biology Building, Iowa City, IA 52242-1324
| | - Felicia K Ooi
- Department of Biology, Aging Mind and Brain Initiative, Iowa Neuroscience Institute, 143 Biology Building, Iowa City, IA 52242-1324
| | - Srijit Das
- Department of Biology, Aging Mind and Brain Initiative, Iowa Neuroscience Institute, 143 Biology Building, Iowa City, IA 52242-1324
| | - Veena Prahlad
- Department of Biology, Aging Mind and Brain Initiative, Iowa Neuroscience Institute, 143 Biology Building, Iowa City, IA 52242-1324
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20
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Ren J, Yuan L, Wang W, Zhang M, Wang Q, Li S, Zhang L, Hu K. Tricetin protects against 6-OHDA-induced neurotoxicity in Parkinson's disease model by activating Nrf2/HO-1 signaling pathway and preventing mitochondria-dependent apoptosis pathway. Toxicol Appl Pharmacol 2019; 378:114617. [DOI: 10.1016/j.taap.2019.114617] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2019] [Revised: 06/03/2019] [Accepted: 06/05/2019] [Indexed: 12/22/2022]
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21
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Stefano GB, Pilonis N, Ptacek R, Raboch J, Vnukova M, Kream RM. Gut, Microbiome, and Brain Regulatory Axis: Relevance to Neurodegenerative and Psychiatric Disorders. Cell Mol Neurobiol 2018; 38:1197-1206. [PMID: 29802603 PMCID: PMC6061125 DOI: 10.1007/s10571-018-0589-2] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Accepted: 05/07/2018] [Indexed: 12/23/2022]
Abstract
It has become apparent that the molecular and biochemical integrity of interactive families, genera, and species of human gut microflora is critically linked to maintaining complex metabolic and behavioral processes mediated by peripheral organ systems and central nervous system neuronal groupings. Relatively recent studies have established intrinsic ratios of enterotypes contained within the human microbiome across demographic subpopulations and have empirically linked significant alterations in the expression of bacterial enterotypes with the initiation and persistence of several major metabolic and psychiatric disorders. Accordingly, the goal of our review is to highlight potential thematic/functional linkages of pathophysiological alterations in gut microbiota and bidirectional gut-brain signaling pathways with special emphasis on the potential roles of gut dysbiosis on the pathophysiology of psychiatric illnesses. We provide critical discussion of putative thematic linkages of Parkinson's disease (PD) data sets to similar pathophysiological events as potential causative factors in the development and persistence of diverse psychiatric illnesses. Finally, we include a concise review of preclinical paradigms that involve immunologically-induced GI deficits and dysbiosis of maternal microflora that are functionally linked to impaired neurodevelopmental processes leading to affective behavioral syndromes in the offspring.
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Affiliation(s)
- G B Stefano
- Department of Psychiatry, First Faculty of Medicine Charles University in Prague and General University Hospital in Prague, Center for Cognitive and Molecular Neuroscience, Ke Karlovu 11, 120 00, Prague 2, Czech Republic.
| | - N Pilonis
- Warsaw Medical University, Public Central Teaching Hospital, Warsaw, Poland
| | - R Ptacek
- Department of Psychiatry, First Faculty of Medicine Charles University in Prague and General University Hospital in Prague, Center for Cognitive and Molecular Neuroscience, Ke Karlovu 11, 120 00, Prague 2, Czech Republic
| | - J Raboch
- Department of Psychiatry, First Faculty of Medicine Charles University in Prague and General University Hospital in Prague, Center for Cognitive and Molecular Neuroscience, Ke Karlovu 11, 120 00, Prague 2, Czech Republic
| | - M Vnukova
- Department of Psychiatry, First Faculty of Medicine Charles University in Prague and General University Hospital in Prague, Center for Cognitive and Molecular Neuroscience, Ke Karlovu 11, 120 00, Prague 2, Czech Republic
| | - R M Kream
- Department of Psychiatry, First Faculty of Medicine Charles University in Prague and General University Hospital in Prague, Center for Cognitive and Molecular Neuroscience, Ke Karlovu 11, 120 00, Prague 2, Czech Republic
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22
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Maulik M, Mitra S, Bult-Ito A, Taylor BE, Vayndorf EM. Behavioral Phenotyping and Pathological Indicators of Parkinson's Disease in C. elegans Models. Front Genet 2017; 8:77. [PMID: 28659967 PMCID: PMC5468440 DOI: 10.3389/fgene.2017.00077] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Accepted: 05/22/2017] [Indexed: 12/14/2022] Open
Abstract
Parkinson's disease (PD) is a neurodegenerative disorder with symptoms that progressively worsen with age. Pathologically, PD is characterized by the aggregation of α-synuclein in cells of the substantia nigra in the brain and loss of dopaminergic neurons. This pathology is associated with impaired movement and reduced cognitive function. The etiology of PD can be attributed to a combination of environmental and genetic factors. A popular animal model, the nematode roundworm Caenorhabditis elegans, has been frequently used to study the role of genetic and environmental factors in the molecular pathology and behavioral phenotypes associated with PD. The current review summarizes cellular markers and behavioral phenotypes in transgenic and toxin-induced PD models of C. elegans.
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Affiliation(s)
- Malabika Maulik
- Department of Chemistry and Biochemistry, University of Alaska FairbanksFairbanks, AK, United States
| | - Swarup Mitra
- Department of Chemistry and Biochemistry, University of Alaska FairbanksFairbanks, AK, United States
| | - Abel Bult-Ito
- Department of Biology and Wildlife, University of Alaska FairbanksFairbanks, AK, United States
| | - Barbara E Taylor
- Department of Biological Sciences, California State University, Long BeachLong Beach, CA, United States
| | - Elena M Vayndorf
- Institute of Arctic Biology, University of Alaska FairbanksFairbanks, AK, United States
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23
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Henne S, Sombke A, Schmidt-Rhaesa A. Immunohistochemical analysis of the anterior nervous system of the free-living nematode Plectus spp. (Nematoda, Plectidae). ZOOMORPHOLOGY 2017. [DOI: 10.1007/s00435-017-0347-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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24
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Loer CM, Calvo AC, Watschinger K, Werner-Felmayer G, O'Rourke D, Stroud D, Tong A, Gotenstein JR, Chisholm AD, Hodgkin J, Werner ER, Martinez A. Cuticle integrity and biogenic amine synthesis in Caenorhabditis elegans require the cofactor tetrahydrobiopterin (BH4). Genetics 2015; 200:237-53. [PMID: 25808955 PMCID: PMC4423366 DOI: 10.1534/genetics.114.174110] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2014] [Accepted: 03/12/2015] [Indexed: 11/18/2022] Open
Abstract
Tetrahydrobiopterin (BH4) is the natural cofactor of several enzymes widely distributed among eukaryotes, including aromatic amino acid hydroxylases (AAAHs), nitric oxide synthases (NOSs), and alkylglycerol monooxygenase (AGMO). We show here that the nematode Caenorhabditis elegans, which has three AAAH genes and one AGMO gene, contains BH4 and has genes that function in BH4 synthesis and regeneration. Knockout mutants for putative BH4 synthetic enzyme genes lack the predicted enzymatic activities, synthesize no BH4, and have indistinguishable behavioral and neurotransmitter phenotypes, including serotonin and dopamine deficiency. The BH4 regeneration enzymes are not required for steady-state levels of biogenic amines, but become rate limiting in conditions of reduced BH4 synthesis. BH4-deficient mutants also have a fragile cuticle and are generally hypersensitive to exogenous agents, a phenotype that is not due to AAAH deficiency, but rather to dysfunction in the lipid metabolic enzyme AGMO, which is expressed in the epidermis. Loss of AGMO or BH4 synthesis also specifically alters the sensitivity of C. elegans to bacterial pathogens, revealing a cuticular function for AGMO-dependent lipid metabolism in host-pathogen interactions.
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Affiliation(s)
- Curtis M Loer
- Department of Biology, University of San Diego, San Diego, California, 92110
| | - Ana C Calvo
- Department of Biomedicine, University of Bergen, 5009 Bergen, Norway
| | - Katrin Watschinger
- Division of Biological Chemistry, Biocenter, Innsbruck Medical University, A-6020 Innsbruck, Austria
| | - Gabriele Werner-Felmayer
- Division of Biological Chemistry, Biocenter, Innsbruck Medical University, A-6020 Innsbruck, Austria
| | - Delia O'Rourke
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, United Kingdom
| | - Dave Stroud
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, United Kingdom
| | - Amy Tong
- Division of Biological Sciences, University of California, San Diego, California 92093
| | - Jennifer R Gotenstein
- Division of Biological Sciences, University of California, San Diego, California 92093
| | - Andrew D Chisholm
- Division of Biological Sciences, University of California, San Diego, California 92093
| | - Jonathan Hodgkin
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, United Kingdom
| | - Ernst R Werner
- Division of Biological Chemistry, Biocenter, Innsbruck Medical University, A-6020 Innsbruck, Austria
| | - Aurora Martinez
- Department of Biomedicine, University of Bergen, 5009 Bergen, Norway
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25
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Wilecki M, Lightfoot JW, Susoy V, Sommer RJ. Predatory feeding behaviour in Pristionchus nematodes is dependent on a phenotypic plasticity and induced by serotonin. J Exp Biol 2015; 218:1306-13. [DOI: 10.1242/jeb.118620] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Accepted: 02/23/2015] [Indexed: 12/29/2022]
Abstract
Behavioural innovation and morphological adaptation are intrinsically linked but their relationship is often poorly understood. In nematodes, a huge diversity of feeding morphologies and behaviours can be observed to meet their distinctive dietary and environmental demands. Pristionchus and their relatives show varied feeding activities consuming both bacteria and also predating other nematodes. In addition, Pristionchus nematodes display dimorphic mouth structures triggered by an irreversible developmental switch, which generates a narrower mouthed form with a single tooth and a wider mouthed form with an additional tooth. However, little is known about the specific predatory adaptations of these mouth forms nor the associated mechanisms and behaviours. Through a mechanistic analysis of predation behaviours, in particular in the model organism Pristionchus pacificus, we reveal multifaceted feeding modes characterised by dynamic rhythmic switching and tooth stimulation. This complex feeding mode switch is regulated by a previously uncharacterised role for the neurotransmitter serotonin, a process which appears conserved across several predatory nematode species. Furthermore, we investigated the effects of starvation, prey size and prey preference on P. pacificus predatory feeding kinetics revealing predation to be a fundamental component of the P. pacificus feeding repertoire thus providing an additional rich source of nutrition in addition to bacteria. Finally, we found that mouth form morphology also has a striking impact on predation suppressing predatory behaviour in the narrow mouthed form. Our results therefore hint at the regulatory networks involved in controlling predatory feeding and underscore P. pacificus as a model for understanding the evolution of complex behaviours.
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Affiliation(s)
- Martin Wilecki
- Max-Planck Institute for Developmental Biology, Dept. for Evolutionary Biology, Spemannstrasse 37, 72076 Tuebingen, Germany
| | - James W. Lightfoot
- Max-Planck Institute for Developmental Biology, Dept. for Evolutionary Biology, Spemannstrasse 37, 72076 Tuebingen, Germany
| | - Vladislav Susoy
- Max-Planck Institute for Developmental Biology, Dept. for Evolutionary Biology, Spemannstrasse 37, 72076 Tuebingen, Germany
| | - Ralf J. Sommer
- Max-Planck Institute for Developmental Biology, Dept. for Evolutionary Biology, Spemannstrasse 37, 72076 Tuebingen, Germany
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Barrière A, Ruvinsky I. Pervasive divergence of transcriptional gene regulation in Caenorhabditis nematodes. PLoS Genet 2014; 10:e1004435. [PMID: 24968346 PMCID: PMC4072541 DOI: 10.1371/journal.pgen.1004435] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2013] [Accepted: 04/28/2014] [Indexed: 12/18/2022] Open
Abstract
Because there is considerable variation in gene expression even between closely related species, it is clear that gene regulatory mechanisms evolve relatively rapidly. Because primary sequence conservation is an unreliable proxy for functional conservation of cis-regulatory elements, their assessment must be carried out in vivo. We conducted a survey of cis-regulatory conservation between C. elegans and closely related species C. briggsae, C. remanei, C. brenneri, and C. japonica. We tested enhancers of eight genes from these species by introducing them into C. elegans and analyzing the expression patterns they drove. Our results support several notable conclusions. Most exogenous cis elements direct expression in the same cells as their C. elegans orthologs, confirming gross conservation of regulatory mechanisms. However, the majority of exogenous elements, when placed in C. elegans, also directed expression in cells outside endogenous patterns, suggesting functional divergence. Recurrent ectopic expression of different promoters in the same C. elegans cells may reflect biases in the directions in which expression patterns can evolve due to shared regulatory logic of coexpressed genes. The fact that, despite differences between individual genes, several patterns repeatedly emerged from our survey, encourages us to think that general rules governing regulatory evolution may exist and be discoverable.
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Affiliation(s)
- Antoine Barrière
- Department of Ecology and Evolution and Institute for Genomics and Systems Biology, The University of Chicago, Chicago, Illinois, United States of America
- * E-mail: (AB); (IR)
| | - Ilya Ruvinsky
- Department of Ecology and Evolution and Institute for Genomics and Systems Biology, The University of Chicago, Chicago, Illinois, United States of America
- Department of Organismal Biology and Anatomy, The University of Chicago, Chicago, Illinois, United States of America
- * E-mail: (AB); (IR)
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Lüersen K, Faust U, Gottschling DC, Döring F. Gait-specific adaptation of locomotor activity in response to dietary restriction in Caenorhabditis elegans. ACTA ACUST UNITED AC 2014; 217:2480-8. [PMID: 24803455 DOI: 10.1242/jeb.099382] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Locomotion is crucial for the survival of living organisms, as it allows foraging, flight and mating behaviour. In response to environmental cues, many organisms switch between alternative forms of locomotion, referred to as gaits. The nematode Caenorhabditis elegans exhibits two gaits: swimming in liquids and crawling on dense gels. The kinematics and patterns of muscle activity differ between the two gaits, with swimming being less efficient than crawling. We found that C. elegans when grown on dietary restriction (DR) plates and then tested immediately for swimming activity exhibit an accelerated frequency of body-bending swimming compared with ad libitum-fed worms, resulting in an increased swimming speed. This response is independent of the presence or absence of food bacteria in the assay liquid. In contrast, the crawling speed of DR worms on assay agar plates is decreased and influenced by food availability. Because DR also attenuates the disturbed swimming activity of worms that are deficient in the presynaptic dopamine transporter DAT-1, our data link DR-induced alterations of the swimming gait to synaptic processes. This strongly suggests a biochemical rather than a biomechanical response to DR provoked by changes in the worm's body structure. We conclude that the increase in locomotor activity in response to DR is specific to the swimming gait and might represent a survival strategy, allowing food-deprived nematodes to exit unfavourable environments.
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Affiliation(s)
- Kai Lüersen
- Department of Molecular Prevention, Institute of Human Nutrition and Food Science, Christian-Albrechts-University of Kiel, Heinrich-Hecht-Platz 10, 24118 Kiel, Germany
| | - Ulla Faust
- Department of Molecular Prevention, Institute of Human Nutrition and Food Science, Christian-Albrechts-University of Kiel, Heinrich-Hecht-Platz 10, 24118 Kiel, Germany
| | - Dieter-Christian Gottschling
- Department of Molecular Prevention, Institute of Human Nutrition and Food Science, Christian-Albrechts-University of Kiel, Heinrich-Hecht-Platz 10, 24118 Kiel, Germany
| | - Frank Döring
- Department of Molecular Prevention, Institute of Human Nutrition and Food Science, Christian-Albrechts-University of Kiel, Heinrich-Hecht-Platz 10, 24118 Kiel, Germany
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Bumbarger DJ, Riebesell M, Rödelsperger C, Sommer RJ. System-wide rewiring underlies behavioral differences in predatory and bacterial-feeding nematodes. Cell 2013; 152:109-19. [PMID: 23332749 DOI: 10.1016/j.cell.2012.12.013] [Citation(s) in RCA: 95] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2012] [Revised: 10/26/2012] [Accepted: 12/07/2012] [Indexed: 10/27/2022]
Abstract
The relationship between neural circuit function and patterns of synaptic connectivity is poorly understood, in part due to a lack of comparative data for larger complete systems. We compare system-wide maps of synaptic connectivity generated from serial transmission electron microscopy for the pharyngeal nervous systems of two nematodes with divergent feeding behavior: the microbivore Caenorhabditis elegans and the predatory nematode Pristionchus pacificus. We uncover a massive rewiring in a complex system of identified neurons, all of which are homologous based on neurite anatomy and cell body position. Comparative graph theoretical analysis reveals a striking pattern of neuronal wiring with increased connectional complexity in the anterior pharynx correlating with tooth-like denticles, a morphological feature in the mouth of P. pacificus. We apply focused centrality methods to identify neurons I1 and I2 as candidates for regulating predatory feeding and predict substantial divergence in the function of pharyngeal glands.
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Affiliation(s)
- Daniel J Bumbarger
- Department for Evolutionary Biology, Max-Planck-Institute for Developmental Biology, Spemannstrasse 37, 72076 Tübingen, Germany
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Kroetz SM, Srinivasan J, Yaghoobian J, Sternberg PW, Hong RL. The cGMP signaling pathway affects feeding behavior in the necromenic nematode Pristionchus pacificus. PLoS One 2012; 7:e34464. [PMID: 22563372 PMCID: PMC3338501 DOI: 10.1371/journal.pone.0034464] [Citation(s) in RCA: 23] [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: 10/13/2011] [Accepted: 03/05/2012] [Indexed: 11/19/2022] Open
Abstract
Background The genetic tractability and the species-specific association with beetles make the nematode Pristionchus pacificus an exciting emerging model organism for comparative studies in development and behavior. P. pacificus differs from Caenorhabditis elegans (a bacterial feeder) by its buccal teeth and the lack of pharyngeal grinders, but almost nothing is known about which genes coordinate P. pacificus feeding behaviors, such as pharyngeal pumping rate, locomotion, and fat storage. Methodology/Principal Findings We analyzed P. pacificus pharyngeal pumping rate and locomotion behavior on and off food, as well as on different species of bacteria (Escherichia coli, Bacillus subtilis, and Caulobacter crescentus). We found that the cGMP-dependent protein kinase G (PKG) Ppa-EGL-4 in P. pacificus plays an important role in regulating the pumping rate, mouth form dimorphism, the duration of forward locomotion, and the amount of fat stored in intestine. In addition, Ppa-EGL-4 interacts with Ppa-OBI-1, a recently identified protein involved in chemosensation, to influence feeding and locomotion behavior. We also found that C. crescentus NA1000 increased pharyngeal pumping as well as fat storage in P. pacificus. Conclusions The PKG EGL-4 has conserved functions in regulating feeding behavior in both C. elegans and P. pacificus nematodes. The Ppa-EGL-4 also has been co-opted during evolution to regulate P. pacificus mouth form dimorphism that indirectly affect pharyngeal pumping rate. Specifically, the lack of Ppa-EGL-4 function increases pharyngeal pumping, time spent in forward locomotion, and fat storage, in part as a result of higher food intake. Ppa-OBI-1 functions upstream or parallel to Ppa-EGL-4. The beetle-associated omnivorous P. pacificus respond differently to changes in food state and food quality compared to the exclusively bacteriovorous C. elegans.
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Affiliation(s)
- Silvina M. Kroetz
- Department of Biology, California State University Northridge, Northridge, California, United States of America
| | - Jagan Srinivasan
- Division of Biology, California Institute of Technology, Pasadena, California, United States of America
| | - Jonathan Yaghoobian
- Department of Biology, California State University Northridge, Northridge, California, United States of America
| | - Paul W. Sternberg
- Division of Biology, California Institute of Technology, Pasadena, California, United States of America
| | - Ray L. Hong
- Department of Biology, California State University Northridge, Northridge, California, United States of America
- * E-mail:
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Chung K, Zhan M, Srinivasan J, Sternberg PW, Gong E, Schroeder FC, Lu H. Microfluidic chamber arrays for whole-organism behavior-based chemical screening. LAB ON A CHIP 2011; 11:3689-3697. [PMID: 21935539 PMCID: PMC3924777 DOI: 10.1039/c1lc20400a] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
The nematode Caenorhabditis elegans is an important model organism in genetic research and drug screening because of its relative simplicity, ease of maintenance, amenability to simple genetic manipulation, and relevance to human biology. However, their small size and mobility make nematodes difficult to physically manipulate, particularly with spatial and temporal precision. We have developed a microfluidic device to overcome these challenges and enable fast behavior-based chemical screening in C. elegans. The key components of this easy-to-use device allow rapid loading and housing of C. elegans in a chamber array for chemical screening. A simple two-step loading process enables simultaneous loading of a large number of animals within a few minutes without using any expensive/active off-chip components. In addition, chemicals can be precisely delivered to the worms and exchanged with high temporal precision. To demonstrate this feature and the ability to measure time dependent responses to chemicals, we characterize the transient response of worms exposed to different concentrations of anesthetics. We then use the device to study the effect of chemical signals from hermaphrodite worms on male behavior. The ability of the device to maintain a large number of free moving animals in one field of view over a long period of time permits us to demonstrate an increase in the incidence of a specific behavior in males subjected to worm-conditioned medium. Because our device allows monitoring of a large number of worms with single-animal resolution, we envision that this platform will greatly expedite chemical screening in C. elegans.
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Affiliation(s)
- Kwanghun Chung
- School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, 311 Ferst Dr, NW, Atlanta, GA, 30332-0100, USA
| | - Mei Zhan
- Interdisciplinary Program of Bioengineering, Georgia Institute of Technology, 311 Ferst Dr, NW, Atlanta, GA, 30332-0100, USA
| | - Jagan Srinivasan
- MC156-29, Biology Division, California Institute of Technology, 1200 East California Blvd, Pasadena, CA, 91125, USA
| | - Paul W. Sternberg
- MC156-29, Biology Division, California Institute of Technology, 1200 East California Blvd, Pasadena, CA, 91125, USA
| | - Emily Gong
- School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, 311 Ferst Dr, NW, Atlanta, GA, 30332-0100, USA
| | - Frank C. Schroeder
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853, USA
| | - Hang Lu
- School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, 311 Ferst Dr, NW, Atlanta, GA, 30332-0100, USA
- Interdisciplinary Program of Bioengineering, Georgia Institute of Technology, 311 Ferst Dr, NW, Atlanta, GA, 30332-0100, USA
- ; Fax: +1-404-894-8473; Tel: +1-404-894-8473
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Regulation of extrasynaptic 5-HT by serotonin reuptake transporter function in 5-HT-absorbing neurons underscores adaptation behavior in Caenorhabditis elegans. J Neurosci 2011; 31:8948-57. [PMID: 21677178 DOI: 10.1523/jneurosci.1692-11.2011] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Serotonin [5-hydroxytryptamine (5-HT)]-absorbing neurons use serotonin reuptake transporter (SERT) to uptake 5-HT from extracellular space but do not synthesize it. While 5-HT-absorbing neurons have been identified in diverse organisms from Caenorhabditis elegans to humans, their function has not been elucidated. Here, we show that SERT in 5-HT-absorbing neurons controls behavioral response to food deprivation in C. elegans. The AIM and RIH interneurons uptake 5-HT released from chemosensory neurons and secretory neurons. Genetic analyses suggest that 5-HT secreted by both synaptic vesicles and dense core vesicles diffuse readily to the extrasynaptic space adjacent to the AIM and RIH neurons. Loss of mod-5/SERT function blocks the 5-HT absorption. mod-5/SERT mutants have been shown to exhibit exaggerated locomotor response to food deprivation. We found that transgenic expression of MOD-5/SERT in the 5-HT-absorbing neurons fully corrected the exaggerated behavior. Experiments of cell-specific inhibition of synaptic transmission suggest that the synaptic release of 5-HT from the 5-HT-absorbing neurons is not required for this behavioral modulation. Our data point to the role of 5-HT-absorbing neurons as temporal-spatial regulators of extrasynaptic 5-HT. Regulation of extrasynaptic 5-HT levels by 5-HT-absorbing neurons may represent a fundamental mechanism of 5-HT homeostasis, integrating the activity of 5-HT-producing neurons with distant targets in the neural circuits, and could be relevant to some actions of selective serotonin reuptake inhibitors in humans.
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32
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Localisation of serotonin and dopamine in Haemonchus contortus. Int J Parasitol 2011; 41:249-54. [DOI: 10.1016/j.ijpara.2010.09.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2010] [Revised: 09/09/2010] [Accepted: 09/10/2010] [Indexed: 11/20/2022]
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Barron AB, Søvik E, Cornish JL. The roles of dopamine and related compounds in reward-seeking behavior across animal phyla. Front Behav Neurosci 2010; 4:163. [PMID: 21048897 PMCID: PMC2967375 DOI: 10.3389/fnbeh.2010.00163] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2010] [Accepted: 08/26/2010] [Indexed: 11/30/2022] Open
Abstract
Motile animals actively seek out and gather resources they find rewarding, and this is an extremely powerful organizer and motivator of animal behavior. Mammalian studies have revealed interconnected neurobiological systems for reward learning, reward assessment, reinforcement and reward-seeking; all involving the biogenic amine dopamine. The neurobiology of reward-seeking behavioral systems is less well understood in invertebrates, but in many diverse invertebrate groups, reward learning and responses to food rewards also involve dopamine. The obvious exceptions are the arthropods in which the chemically related biogenic amine octopamine has a greater effect on reward learning and reinforcement than dopamine. Here we review the functions of these biogenic amines in behavioral responses to rewards in different animal groups, and discuss these findings in an evolutionary context.
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Affiliation(s)
- Andrew B Barron
- Department of Biology, Macquarie University Sydney, NSW, Australia
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