1
|
Mo A, Liang Y, Cao X, Jiang J, Liu Y, Cao X, Qiu Y, He D. Polymer chain extenders induce significant toxicity through DAF-16 and SKN-1 pathways in Caenorhabditis elegans: A comparative analysis. JOURNAL OF HAZARDOUS MATERIALS 2024; 473:134730. [PMID: 38797076 DOI: 10.1016/j.jhazmat.2024.134730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Revised: 05/19/2024] [Accepted: 05/23/2024] [Indexed: 05/29/2024]
Abstract
Polymer chain extenders, commonly used in plastic production, have garnered increasing attention due to their potential environmental impacts. However, a comprehensive understanding of their ecological risks remains largely unknown. In this study, we employed the model organism Caenorhabditis elegans to investigate toxicological profiles of ten commonly-used chain extenders. Exposure to environmentally relevant concentrations of these chain extenders (ranging from 0.1 µg L-1 to 10 mg L-1) caused significant variations in toxicity. Lethality assays demonstrated the LC50 values ranged from 92.42 µg L-1 to 1553.65 mg L-1, indicating marked differences in acute toxicity. Sublethal exposures could inhibit nematodes' growth, shorten lifespan, and induce locomotor deficits, neuronal damage, and reproductive toxicity. Molecular analyses further elucidated the involvement of the DAF-16 and SKN-1 signaling pathways, as evidenced by upregulated expression of genes including ctl-1,2,3, sod-3, gcs-1, and gst-4. It implicates these pathways in mediating oxidative stress and toxicities induced by chain extenders. Particularly, hexamethylene diisocyanate and diallyl maleate exhibited markedly high toxicity among the chain extenders, as revealed through a comparative analysis of multiple endpoints. These findings demonstrate the potential ecotoxicological risks of polymer chain extenders, and suggest the need for more rigorous environmental safety assessments.
Collapse
Affiliation(s)
- Aoyun Mo
- School of Ecological and Environmental Sciences, Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, East China Normal University, Shanghai 200241, China
| | - Yuqing Liang
- School of Ecological and Environmental Sciences, Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, East China Normal University, Shanghai 200241, China
| | - Xiaomu Cao
- School of Ecological and Environmental Sciences, Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, East China Normal University, Shanghai 200241, China; Shanghai Key Laboratory for Urban Ecological Processes and Eco-Restoration, East China Normal University, Shanghai 200241, China
| | - Jie Jiang
- School of Ecological and Environmental Sciences, Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, East China Normal University, Shanghai 200241, China; Shanghai Key Laboratory for Urban Ecological Processes and Eco-Restoration, East China Normal University, Shanghai 200241, China
| | - Yan Liu
- School of Ecological and Environmental Sciences, Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, East China Normal University, Shanghai 200241, China
| | - Xuelong Cao
- School of Ecological and Environmental Sciences, Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, East China Normal University, Shanghai 200241, China
| | - Yuping Qiu
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Defu He
- School of Ecological and Environmental Sciences, Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, East China Normal University, Shanghai 200241, China; Shanghai Key Laboratory for Urban Ecological Processes and Eco-Restoration, East China Normal University, Shanghai 200241, China; Technology Innovation Center for Land Spatial Eco-restoration in Metropolitan Area, Ministry of Natural Resources, Shanghai 200062, China.
| |
Collapse
|
2
|
Liu J, Lei M, Wang M, Chen S, Tu H. Protocol for survival assay of Caenorhabditis elegans to Pseudomonas aeruginosa PA14 infection. STAR Protoc 2024; 5:103070. [PMID: 38768031 PMCID: PMC11111813 DOI: 10.1016/j.xpro.2024.103070] [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: 11/28/2023] [Revised: 02/07/2024] [Accepted: 04/26/2024] [Indexed: 05/22/2024] Open
Abstract
The nematode Caenorhabditis elegans is a powerful model organism for studying the molecular and cellular mechanisms of innate immunity governed by the intestine. Here, we present a protocol to perform C. elegans survival assays to infection by the bacterial pathogen Pseudomonas aeruginosa PA14. Specifically, we describe steps for preparing C. elegans strains and PA14 bacteria for survival assays. This protocol will assist researchers to study genes involved in intestinal innate immunity and gut defense against pathogen infection. For complete details on the use and execution of this protocol, please refer to Liu et al.1 and Zheng et al.2.
Collapse
Affiliation(s)
- Junqiang Liu
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, Hunan University, Changsha, Hunan 410082, China.
| | - Ming Lei
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, Hunan University, Changsha, Hunan 410082, China
| | - Mengqi Wang
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, Hunan University, Changsha, Hunan 410082, China
| | - Shu Chen
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, Hunan University, Changsha, Hunan 410082, China
| | - Haijun Tu
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, Hunan University, Changsha, Hunan 410082, China.
| |
Collapse
|
3
|
Gadhia A, Barker E, Morgan A, Barclay JW. Functional analysis of epilepsy-associated GABA A receptor mutations using Caenorhabditis elegans. Epilepsia Open 2024. [PMID: 38813985 DOI: 10.1002/epi4.12982] [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: 01/24/2024] [Revised: 05/03/2024] [Accepted: 05/18/2024] [Indexed: 05/31/2024] Open
Abstract
OBJECTIVE GABAA receptor subunit mutations pose a significant risk for genetic generalized epilepsy; however, there are over 150 identified variants, many with unknown or unvalidated pathogenicity. We aimed to develop in vivo models for testing GABAA receptor variants using the model organism, Caenorhabditis elegans. METHODS CRISPR-Cas9 gene editing was used to create a complete deletion of unc-49, a C. elegans GABAA receptor, and to create homozygous epilepsy-associated mutations in the endogenous unc-49 gene. The unc-49 deletion strain was rescued with transgenes for either the C. elegans unc-49B subunit or the α1, β3, and γ2 subunits for the human GABAA receptor. All newly created strains were analyzed for phenotype and compared against existing unc-49 mutations. RESULTS Nematodes with a full genetic deletion of the entire unc-49 locus were compared with existing unc-49 mutations in three separate phenotypic assays-coordinated locomotion, shrinker frequency and seizure-like convulsions. The full unc-49 deletion exhibited reduced locomotion and increased shrinker frequency and PTZ-induced convulsions, but were not found to be phenotypically stronger than existing unc-49 mutations. Rescue with the unc-49B subunit or creation of humanized worms for the GABAA receptor both showed partial phenotypic rescue for all three phenotypes investigated. Finally, two epilepsy-associated variants were analyzed and deemed to be loss of function, thus validating their pathogenicity. SIGNIFICANCE These findings establish C. elegans as a genetic model to investigate GABAA receptor mutations and delineate a platform for validating associated variants in any epilepsy-associated gene. PLAIN LANGUAGE SUMMARY Epilepsy is a complex human disease that can be caused by mutations in specific genes. Many possible mutations have been identified, but it is unknown for most of them whether they cause the disease. We tested the role of mutations in one specific gene using a small microscopic worm as an animal model. Our results establish this worm as a model for epilepsy and confirm that the two unknown mutations are likely to cause the disease.
Collapse
Affiliation(s)
- Ami Gadhia
- Department of Biochemistry, Cell and Systems Biology, ISMIB, University of Liverpool, Liverpool, UK
| | - Eleanor Barker
- Department of Biochemistry, Cell and Systems Biology, ISMIB, University of Liverpool, Liverpool, UK
| | - Alan Morgan
- Department of Biochemistry, Cell and Systems Biology, ISMIB, University of Liverpool, Liverpool, UK
| | - Jeff W Barclay
- Department of Biochemistry, Cell and Systems Biology, ISMIB, University of Liverpool, Liverpool, UK
| |
Collapse
|
4
|
Gorelik MG, Yakhnin H, Pannuri A, Walker AC, Pourciau C, Czyz D, Romeo T, Babitzke P. Multitier regulation of the E. coli extreme acid stress response by CsrA. J Bacteriol 2024; 206:e0035423. [PMID: 38319100 PMCID: PMC11210196 DOI: 10.1128/jb.00354-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Accepted: 01/15/2024] [Indexed: 02/07/2024] Open
Abstract
CsrA is an RNA-binding protein that regulates processes critical for growth and survival, including central carbon metabolism, motility, biofilm formation, stress responses, and expression of virulence factors in pathogens. Transcriptomics studies in Escherichia coli suggested that CsrA repressed genes involved in surviving extremely acidic conditions. Here, we examine the effects of disrupting CsrA-dependent regulation on the expression of genes and circuitry for acid stress survival and demonstrate CsrA-mediated repression at multiple levels. We show that this repression is critical for managing the trade-off between growth and survival; overexpression of acid stress genes caused by csrA disruption enhances survival under extreme acidity but is detrimental for growth under mildly acidic conditions. In vitro studies confirmed that CsrA binds specifically to mRNAs of structural and regulatory genes for acid stress survival, causing translational repression. We also found that translation of the top-tier acid stress regulator, evgA, is coupled to that of a small leader peptide, evgL, which is repressed by CsrA. Unlike dedicated acid stress response genes, csrA and its sRNA antagonists, csrB and csrC, did not exhibit a substantial response to acid shock. Furthermore, disruption of CsrA regulation of acid stress genes impacted host-microbe interactions in Caenorhabditis elegans, alleviating GABA deficiencies. This study expands the known regulon of CsrA to genes of the extreme acid stress response of E. coli and highlights a new facet of the global role played by CsrA in balancing the opposing physiological demands of stress resistance with the capacity for growth and modulating host interactions.IMPORTANCETo colonize/infect the mammalian intestinal tract, bacteria must survive exposure to the extreme acidity of the stomach. E. coli does this by expressing proteins that neutralize cytoplasmic acidity and cope with molecular damage caused by low pH. Because of the metabolic cost of these processes, genes for surviving acid stress are tightly regulated. Here, we show that CsrA negatively regulates the cascade of expression responsible for the acid stress response. Increased expression of acid response genes due to csrA disruption improved survival at extremely low pH but inhibited growth under mildly acidic conditions. Our findings define a new layer of regulation in the acid stress response of E. coli and a novel physiological function for CsrA.
Collapse
Affiliation(s)
- Mark G. Gorelik
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, Florida, USA
| | - Helen Yakhnin
- Department of Biochemistry and Molecular Biology, Center for RNA Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Archana Pannuri
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, Florida, USA
| | - Alyssa C. Walker
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, Florida, USA
| | - Christine Pourciau
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, Florida, USA
- Department of Biochemistry and Molecular Biology, Center for RNA Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Daniel Czyz
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, Florida, USA
| | - Tony Romeo
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, Florida, USA
| | - Paul Babitzke
- Department of Biochemistry and Molecular Biology, Center for RNA Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, USA
| |
Collapse
|
5
|
Rathor L, Curry S, Park Y, McElroy T, Robles B, Sheng Y, Chen WW, Min K, Xiao R, Lee MH, Han SM. Mitochondrial stress in GABAergic neurons non-cell autonomously regulates organismal health and aging. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.20.585932. [PMID: 38585797 PMCID: PMC10996468 DOI: 10.1101/2024.03.20.585932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
Mitochondrial stress within the nervous system can trigger non-cell autonomous responses in peripheral tissues. However, the specific neurons involved and their impact on organismal aging and health have remained incompletely understood. Here, we demonstrate that mitochondrial stress in γ-aminobutyric acid-producing (GABAergic) neurons in Caenorhabditis elegans ( C. elegans ) is sufficient to significantly alter organismal lifespan, stress tolerance, and reproductive capabilities. This mitochondrial stress also leads to significant changes in mitochondrial mass, energy production, and levels of reactive oxygen species (ROS). DAF-16/FoxO activity is enhanced by GABAergic neuronal mitochondrial stress and mediates the induction of these non-cell-autonomous effects. Moreover, our findings indicate that GABA signaling operates within the same pathway as mitochondrial stress in GABAergic neurons, resulting in non-cell-autonomous alterations in organismal stress tolerance and longevity. In summary, these data suggest the crucial role of GABAergic neurons in detecting mitochondrial stress and orchestrating non-cell-autonomous changes throughout the organism.
Collapse
|
6
|
Zhao MM, Li LD, Yang MM, Yao L, Wang Q, Zeng KW. Identification of Skp1 as a target of mercury sulfide for neuroprotection. Chem Commun (Camb) 2024; 60:1464-1467. [PMID: 38223951 DOI: 10.1039/d3cc05141b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2024]
Abstract
Mercury sulfide (HgS) exerts extensive biological effects on neuronal function. To investigate the direct target of HgS in neuronal cells, we developed a biotin-tagged HgS probe (bio-HgS) and employed an affinity purification technique to capture its target proteins. Then, we identified S-phase kinase-associated protein 1 (Skp1) as a potential target of HgS. Unexpectedly, we discovered that HgS covalently binds to Skp1 through a "Cys62-HgS-Cys120" mode. Moreover, our findings revealed that HgS inhibits the ubiquitin-protease system through Skp1 to up-regulate SNAP-25 expression, thereby triggering synaptic vesicle exocytosis to regulate locomotion ability in C. elegans. Collectively, our findings may promote a comprehensive interpretation of the pharmacological mechanism of mercury sulfide on neuroprotective function.
Collapse
Affiliation(s)
- Mei-Mei Zhao
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing, 100191, China.
| | - Lu-Di Li
- Department of Toxicology, School of Public Health, Peking University, Beijing, 100191, China.
| | - Mi-Mi Yang
- Department of Toxicology, School of Public Health, Peking University, Beijing, 100191, China.
| | - Lu Yao
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing, 100191, China.
| | - Qi Wang
- Department of Toxicology, School of Public Health, Peking University, Beijing, 100191, China.
- Key Laboratory of State Administration of Traditional Chinese Medicine for Compatibility Toxicology, Beijing, 100191, China
- Beijing Key Laboratory of Toxicological Research and Risk Assessment for Food Safety, Beijing, 100191, China
| | - Ke-Wu Zeng
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing, 100191, China.
| |
Collapse
|
7
|
Wolfe AD, Koberstein JN, Smith CB, Stewart ML, Gonzalez IJ, Hammarlund M, Hyman AA, Stork PJS, Goodman RH, Colón-Ramos DA. Local and dynamic regulation of neuronal glycolysis in vivo. Proc Natl Acad Sci U S A 2024; 121:e2314699121. [PMID: 38198527 PMCID: PMC10801914 DOI: 10.1073/pnas.2314699121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Accepted: 12/01/2023] [Indexed: 01/12/2024] Open
Abstract
Energy metabolism supports neuronal function. While it is well established that changes in energy metabolism underpin brain plasticity and function, less is known about how individual neurons modulate their metabolic states to meet varying energy demands. This is because most approaches used to examine metabolism in living organisms lack the resolution to visualize energy metabolism within individual circuits, cells, or subcellular regions. Here, we adapted a biosensor for glycolysis, HYlight, for use in Caenorhabditis elegans to image dynamic changes in glycolysis within individual neurons and in vivo. We determined that neurons cell-autonomously perform glycolysis and modulate glycolytic states upon energy stress. By examining glycolysis in specific neurons, we documented a neuronal energy landscape comprising three general observations: 1) glycolytic states in neurons are diverse across individual cell types; 2) for a given condition, glycolytic states within individual neurons are reproducible across animals; and 3) for varying conditions of energy stress, glycolytic states are plastic and adapt to energy demands. Through genetic analyses, we uncovered roles for regulatory enzymes and mitochondrial localization in the cellular and subcellular dynamic regulation of glycolysis. Our study demonstrates the use of a single-cell glycolytic biosensor to examine how energy metabolism is distributed across cells and coupled to dynamic states of neuronal function and uncovers unique relationships between neuronal identities and metabolic landscapes in vivo.
Collapse
Affiliation(s)
- Aaron D. Wolfe
- Department of Neuroscience, Yale University School of Medicine, New Haven, CT06536
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT06536
| | | | - Chadwick B. Smith
- Vollum Institute, Oregon Health & Science University, Portland, OR97239
| | | | - Ian J. Gonzalez
- Department of Neuroscience, Yale University School of Medicine, New Haven, CT06536
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT06536
| | - Marc Hammarlund
- Department of Neuroscience, Yale University School of Medicine, New Haven, CT06536
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT06536
| | - Anthony A. Hyman
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden01307, Germany
| | | | - Richard H. Goodman
- Department of Neuroscience, Yale University School of Medicine, New Haven, CT06536
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT06536
- Vollum Institute, Oregon Health & Science University, Portland, OR97239
| | - Daniel A. Colón-Ramos
- Department of Neuroscience, Yale University School of Medicine, New Haven, CT06536
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT06536
- Wu Tsai Institute, Yale University, New Haven, CT06510
| |
Collapse
|
8
|
Lee MB, Blue B, Muir M, Kaeberlein M. The million-molecule challenge: a moonshot project to rapidly advance longevity intervention discovery. GeroScience 2023; 45:3103-3113. [PMID: 37432607 PMCID: PMC10643437 DOI: 10.1007/s11357-023-00867-6] [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: 05/16/2023] [Accepted: 06/30/2023] [Indexed: 07/12/2023] Open
Abstract
Targeting aging is the future of twenty-first century preventative medicine. Small molecule interventions that promote healthy longevity are known, but few are well-developed and discovery of novel, robust interventions has stagnated. To accelerate longevity intervention discovery and development, high-throughput systems are needed that can perform unbiased drug screening and directly measure lifespan and healthspan metrics in whole animals. C. elegans is a powerful model system for this type of drug discovery. Combined with automated data capture and analysis technologies, truly high-throughput longevity drug discovery is possible. In this perspective, we propose the "million-molecule challenge", an effort to quantitatively assess 1,000,000 interventions for longevity within five years. The WormBot-AI, our best-in-class robotics and AI data analysis platform, provides a tool to achieve the million-molecule challenge for pennies per animal tested.
Collapse
Affiliation(s)
- Mitchell B Lee
- Ora Biomedical, Inc., 12101 Tukwila International Blvd Suite 210, Seattle, WA, 98168, USA.
| | - Benjamin Blue
- Ora Biomedical, Inc., 12101 Tukwila International Blvd Suite 210, Seattle, WA, 98168, USA
| | - Michael Muir
- Ora Biomedical, Inc., 12101 Tukwila International Blvd Suite 210, Seattle, WA, 98168, USA
| | - Matt Kaeberlein
- Ora Biomedical, Inc., 12101 Tukwila International Blvd Suite 210, Seattle, WA, 98168, USA
- Optispan Geroscience, Seattle, WA, USA
| |
Collapse
|
9
|
Wolfe AD, Koberstein JN, Smith CB, Stewart ML, Hammarlund M, Hyman A, Stork PJ, Goodman R, Colón-Ramos DA. Local and dynamic regulation of neuronal glycolysis in vivo. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.25.554774. [PMID: 37662365 PMCID: PMC10473759 DOI: 10.1101/2023.08.25.554774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/05/2023]
Abstract
Energy metabolism supports neuronal function. While it is well established that changes in energy metabolism underpin brain plasticity and function, less is known about how individual neurons modulate their metabolic states to meet varying energy demands. This is because most approaches used to examine metabolism in living organisms lack the resolution to visualize energy metabolism within individual circuits, cells, or subcellular regions. Here we adapted a biosensor for glycolysis, HYlight, for use in C. elegans to image dynamic changes in glycolysis within individual neurons and in vivo. We determined that neurons perform glycolysis cell-autonomously, and modulate glycolytic states upon energy stress. By examining glycolysis in specific neurons, we documented a neuronal energy landscape comprising three general observations: 1) glycolytic states in neurons are diverse across individual cell types; 2) for a given condition, glycolytic states within individual neurons are reproducible across animals; and 3) for varying conditions of energy stress, glycolytic states are plastic and adapt to energy demands. Through genetic analyses, we uncovered roles for regulatory enzymes and mitochondrial localization in the cellular and subcellular dynamic regulation of glycolysis. Our study demonstrates the use of a single-cell glycolytic biosensor to examine how energy metabolism is distributed across cells and coupled to dynamic states of neuronal function, and uncovers new relationships between neuronal identities and metabolic landscapes in vivo.
Collapse
Affiliation(s)
- Aaron D Wolfe
- Department of Neuroscience and Department of Cell Biology, Yale University School of Medicine; New Haven, CT 06536, USA
| | - John N Koberstein
- Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Chadwick B Smith
- Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Melissa L Stewart
- Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Marc Hammarlund
- Department of Neuroscience and Department of Cell Biology, Yale University School of Medicine; New Haven, CT 06536, USA
| | - Anthony Hyman
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstraße 108, Dresden, Germany
| | - Philip Js Stork
- Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Richard Goodman
- Department of Neuroscience and Department of Cell Biology, Yale University School of Medicine; New Haven, CT 06536, USA
- Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Daniel A Colón-Ramos
- Department of Neuroscience and Department of Cell Biology, Yale University School of Medicine; New Haven, CT 06536, USA
- Wu Tsai Institute, Yale University; New Haven, CT 06510, USA
| |
Collapse
|
10
|
Liu J, Zhang P, Zheng Z, Afridi MI, Zhang S, Wan Z, Zhang X, Stingelin L, Wang Y, Tu H. GABAergic signaling between enteric neurons and intestinal smooth muscle promotes innate immunity and gut defense in Caenorhabditis elegans. Immunity 2023; 56:1515-1532.e9. [PMID: 37437538 DOI: 10.1016/j.immuni.2023.06.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 03/06/2023] [Accepted: 06/07/2023] [Indexed: 07/14/2023]
Abstract
The nervous system is critical for intestinal homeostasis and function, but questions remain regarding its impact on gut immune defense. By screening the major neurotransmitters of C. elegans, we found that γ-aminobutyric acid (GABA) deficiency enhanced susceptibility to pathogenic Pseudomonas aeruginosa PA14 infection. GABAergic signaling between enteric neurons and intestinal smooth muscle promoted gut defense in a PMK-1/p38-dependent, but IIS/DAF-16- and DBL-1/TGF-β-independent, pathway. Transcriptomic profiling revealed that the neuropeptide, FLP-6, acted downstream of enteric GABAergic signaling. Further data determined that FLP-6 was expressed and secreted by intestinal smooth muscle cells and functioned as a paracrine molecule on the intestinal epithelium. FLP-6 suppressed the transcription factors ZIP-10 and KLF-1 that worked in parallel and converged to the PMK-1/p38 pathway in the intestinal epithelia for innate immunity and gut defense. Collectively, these findings uncover an enteric neuron-muscle-epithelium axis that may be evolutionarily conserved in higher organisms.
Collapse
Affiliation(s)
- Junqiang Liu
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, Hunan University, Changsha 410082, Hunan, China
| | - Pei Zhang
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, Hunan University, Changsha 410082, Hunan, China
| | - Zhongfan Zheng
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, Hunan University, Changsha 410082, Hunan, China
| | - Muhammad Irfan Afridi
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, Hunan University, Changsha 410082, Hunan, China
| | - Shan Zhang
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, Hunan University, Changsha 410082, Hunan, China
| | - Zhiqing Wan
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, Hunan University, Changsha 410082, Hunan, China
| | - Xiumei Zhang
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, Hunan University, Changsha 410082, Hunan, China
| | - Lukas Stingelin
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, Hunan University, Changsha 410082, Hunan, China
| | - Yirong Wang
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, Hunan University, Changsha 410082, Hunan, China
| | - Haijun Tu
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, Hunan University, Changsha 410082, Hunan, China.
| |
Collapse
|
11
|
Ayub S, Malak N, Cossío-Bayúgar R, Nasreen N, Khan A, Niaz S, Khan A, Alanazi AD, Ben Said M. In Vitro and In Silico Protocols for the Assessment of Anti-Tick Compounds from Pinus roxburghii against Rhipicephalus (Boophilus) microplus Ticks. Animals (Basel) 2023; 13:ani13081388. [PMID: 37106951 PMCID: PMC10135231 DOI: 10.3390/ani13081388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2022] [Revised: 04/10/2023] [Accepted: 04/12/2023] [Indexed: 04/29/2023] Open
Abstract
Pinus roxburghii, also known by the name "Himalayan chir pine," belongs to the Pinaceae family. Rhipicephalus (Boophilus) microplus tick is one of the most significant bovine ectoparasites, making it a major vector of economically important tick-borne diseases. The researchers conducted adult immersion tests (AIT) and larval packet tests (LPT) to investigate the acaricidal effect of P. roxburghii plant extract on R. (B.) microplus and its potential modulatory function when used with cypermethrin. Eggs were also assessed for their weight, egg-laying index (IE), hatchability rate, and control rate. After exposure to essential extract concentrations ranging from 2.5 to 40 mg/mL for 48 h, adult female ticks' oviposition inhibition and unfed R. (B.) microplus larvae's mortality rates were analyzed. Engorged females exposed to P. roxburghii at 40 mg/mL had reduced biological activity (oviposition, IE) compared to positive and negative controls. A concentration of 40 mg/mL of P. roxburghii caused 90% mortality in R. (B.) microplus larvae, whereas cypermethrin (the positive control) caused 98.3% mortality in LPT. In AIT, cypermethrin inhibited 81% of oviposition, compared to the 40 mg/mL concentration of P. roxburghii, which inhibited 40% of the ticks' oviposition. Moreover, this study assessed the binding capacity of selected phytocompounds with the targeted protein. Three servers (SWISS-MODEL, RoseTTAFold, and TrRosetta) recreated the target protein RmGABACl's 3D structure. The modeled 3D structure was validated using the online servers PROCHECK, ERRAT, and Prosa. Molecular docking using Auto Dock VINA predicted the binding mechanisms of 20 drug-like compounds against the target protein. Catechin and myricetin showed significant interactions with active site residues of the target protein, with docking scores of -7.7 kcal/mol and -7.6 kcal/mol, respectively. In conclusion, this study demonstrated the acaricidal activity of P. roxburghii extract, suggesting its potential as an alternative natural acaricide for controlling R. (B.) microplus.
Collapse
Affiliation(s)
- Sana Ayub
- Department of Zoology, Abdul Wali Khan University Mardan, Mardan 23200, Pakistan
| | - Nosheen Malak
- Department of Zoology, Abdul Wali Khan University Mardan, Mardan 23200, Pakistan
| | - Raquel Cossío-Bayúgar
- Centro Nacional de Investigaciones Disciplinarias en Salud Animal e Inocuidad, Departamento de Artropodología, Instituto Nacional de Investigaciones Forestales Agrícolas y Pecuarias (INIFAP), Boulevard Cuauhnahuac No. 8534, Jiutepec 62574, Mexico
| | - Nasreen Nasreen
- Department of Zoology, Abdul Wali Khan University Mardan, Mardan 23200, Pakistan
| | - Afshan Khan
- Department of Zoology, Abdul Wali Khan University Mardan, Mardan 23200, Pakistan
| | - Sadaf Niaz
- Department of Zoology, Abdul Wali Khan University Mardan, Mardan 23200, Pakistan
| | - Adil Khan
- Department of Zoology, Bacha Khan University Charsadda, Charsadda 24420, Pakistan
| | - Abdallah D Alanazi
- Department of Biological Sciences, Faculty of Science and Humanities, Shaqra University, Ad-Dawadimi 11911, Saudi Arabia
| | - Mourad Ben Said
- Department of Basic Sciences, Higher Institute of Biotechnology of Sidi Thabet, University of Manouba, Manouba 2010, Tunisia
- Laboratory of Microbiology, National School of Veterinary Medicine, Sidi Thabet, University of Manouba, Manouba 2010, Tunisia
| |
Collapse
|
12
|
Zhao P, Mondal S, Martin C, DuPlissis A, Chizari S, Ma KY, Maiya R, Messing RO, Jiang N, Ben-Yakar A. Femtosecond laser microdissection for isolation of regenerating C. elegans neurons for single-cell RNA sequencing. Nat Methods 2023; 20:590-599. [PMID: 36928074 DOI: 10.1038/s41592-023-01804-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Accepted: 01/26/2023] [Indexed: 03/18/2023]
Abstract
Our understanding of nerve regeneration can be enhanced by delineating its underlying molecular activities at single-neuron resolution in model organisms such as Caenorhabditis elegans. Existing cell isolation techniques cannot isolate neurons with specific regeneration phenotypes from C. elegans. We present femtosecond laser microdissection (fs-LM), a single-cell isolation method that dissects specific cells directly from living tissue by leveraging the micrometer-scale precision of fs-laser ablation. We show that fs-LM facilitates sensitive and specific gene expression profiling by single-cell RNA sequencing (scRNA-seq), while mitigating the stress-related transcriptional artifacts induced by tissue dissociation. scRNA-seq of fs-LM isolated regenerating neurons revealed transcriptional programs that are correlated with either successful or failed regeneration in wild-type and dlk-1 (0) animals, respectively. This method also allowed studying heterogeneity displayed by the same type of neuron and found gene modules with expression patterns correlated with axon regrowth rate. Our results establish fs-LM as a spatially resolved single-cell isolation method for phenotype-to-genotype mapping.
Collapse
Affiliation(s)
- Peisen Zhao
- Department of Electrical and Computer Engineering, The University of Texas at Austin, Austin, TX, USA
| | - Sudip Mondal
- Department of Mechanical Engineering, The University of Texas at Austin, Austin, TX, USA
| | - Chris Martin
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX, USA
| | - Andrew DuPlissis
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX, USA
| | - Shahab Chizari
- Deparment of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
| | - Ke-Yue Ma
- Interdisciplinary Life Sciences Graduate Programs, The University of Texas at Austin, Austin, TX, USA
| | - Rajani Maiya
- Department of Neuroscience, The University of Texas at Austin, Austin, TX, USA
- Department of Neurology, Dell Medical School, The University of Texas at Austin, Austin, TX, USA
- Institute of Neuroscience, The University of Texas at Austin, Austin, TX, USA
- Department of Physiology, LSU Health Sciences Center, New Orleans, LA, USA
| | - Robert O Messing
- Department of Neuroscience, The University of Texas at Austin, Austin, TX, USA
- Department of Neurology, Dell Medical School, The University of Texas at Austin, Austin, TX, USA
- Institute of Neuroscience, The University of Texas at Austin, Austin, TX, USA
| | - Ning Jiang
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX, USA
- Deparment of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
- Interdisciplinary Life Sciences Graduate Programs, The University of Texas at Austin, Austin, TX, USA
| | - Adela Ben-Yakar
- Department of Electrical and Computer Engineering, The University of Texas at Austin, Austin, TX, USA.
- Department of Mechanical Engineering, The University of Texas at Austin, Austin, TX, USA.
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX, USA.
- Institute of Neuroscience, The University of Texas at Austin, Austin, TX, USA.
| |
Collapse
|
13
|
Hao Y, Liu H, Zeng XT, Wang Y, Zeng WX, Qian KY, Li L, Chi MX, Gao S, Hu Z, Tong XJ. UNC-43/CaMKII-triggered anterograde signals recruit GABA ARs to mediate inhibitory synaptic transmission and plasticity at C. elegans NMJs. Nat Commun 2023; 14:1436. [PMID: 36918518 PMCID: PMC10015018 DOI: 10.1038/s41467-023-37137-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2022] [Accepted: 02/28/2023] [Indexed: 03/16/2023] Open
Abstract
Disturbed inhibitory synaptic transmission has functional impacts on neurodevelopmental and psychiatric disorders. An essential mechanism for modulating inhibitory synaptic transmission is alteration of the postsynaptic abundance of GABAARs, which are stabilized by postsynaptic scaffold proteins and recruited by presynaptic signals. However, how GABAergic neurons trigger signals to transsynaptically recruit GABAARs remains elusive. Here, we show that UNC-43/CaMKII functions at GABAergic neurons to recruit GABAARs and modulate inhibitory synaptic transmission at C. elegans neuromuscular junctions. We demonstrate that UNC-43 promotes presynaptic MADD-4B/Punctin secretion and NRX-1α/Neurexin surface delivery. Together, MADD-4B and NRX-1α recruit postsynaptic NLG-1/Neuroligin and stabilize GABAARs. Further, the excitation of GABAergic neurons potentiates the recruitment of NLG-1-stabilized-GABAARs, which depends on UNC-43, MADD-4B, and NRX-1. These data all support that UNC-43 triggers MADD-4B and NRX-1α, which act as anterograde signals to recruit postsynaptic GABAARs. Thus, our findings elucidate a mechanism for pre- and postsynaptic communication and inhibitory synaptic transmission and plasticity.
Collapse
Affiliation(s)
- Yue Hao
- School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
- University of Chinese Academy of Sciences, Beijing, 100190, China
| | - Haowen Liu
- Queensland Brain Institute, Clem Jones Centre for Ageing Dementia Research (CJCADR), The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Xian-Ting Zeng
- School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Ya Wang
- College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Wan-Xin Zeng
- School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
- University of Chinese Academy of Sciences, Beijing, 100190, China
| | - Kang-Ying Qian
- School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
- University of Chinese Academy of Sciences, Beijing, 100190, China
| | - Lei Li
- Queensland Brain Institute, Clem Jones Centre for Ageing Dementia Research (CJCADR), The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Ming-Xuan Chi
- School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Shangbang Gao
- College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Zhitao Hu
- Queensland Brain Institute, Clem Jones Centre for Ageing Dementia Research (CJCADR), The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Xia-Jing Tong
- School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China.
| |
Collapse
|
14
|
Caenorhabditis elegans as a Model System to Study Human Neurodegenerative Disorders. Biomolecules 2023; 13:biom13030478. [PMID: 36979413 PMCID: PMC10046667 DOI: 10.3390/biom13030478] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2023] [Revised: 02/18/2023] [Accepted: 03/01/2023] [Indexed: 03/08/2023] Open
Abstract
In recent years, advances in science and technology have improved our quality of life, enabling us to tackle diseases and increase human life expectancy. However, longevity is accompanied by an accretion in the frequency of age-related neurodegenerative diseases, creating a growing burden, with pervasive social impact for human societies. The cost of managing such chronic disorders and the lack of effective treatments highlight the need to decipher their molecular and genetic underpinnings, in order to discover new therapeutic targets. In this effort, the nematode Caenorhabditis elegans serves as a powerful tool to recapitulate several disease-related phenotypes and provides a highly malleable genetic model that allows the implementation of multidisciplinary approaches, in addition to large-scale genetic and pharmacological screens. Its anatomical transparency allows the use of co-expressed fluorescent proteins to track the progress of neurodegeneration. Moreover, the functional conservation of neuronal processes, along with the high homology between nematode and human genomes, render C. elegans extremely suitable for the study of human neurodegenerative disorders. This review describes nematode models used to study neurodegeneration and underscores their contribution in the effort to dissect the molecular basis of human diseases and identify novel gene targets with therapeutic potential.
Collapse
|
15
|
Li X, Chen Y, Gao W, Mo A, Zhang Y, Jiang J, He D. Prominent toxicity of isocyanates and maleic anhydrides to Caenorhabditis elegans: Multilevel assay for typical organic additives of biodegradable plastics. JOURNAL OF HAZARDOUS MATERIALS 2023; 442:130051. [PMID: 36179627 DOI: 10.1016/j.jhazmat.2022.130051] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 09/02/2022] [Accepted: 09/21/2022] [Indexed: 06/16/2023]
Abstract
Biodegradable plastics (BDP) are increasingly applied; however, there has been of concerns about their environmental safety, especially from nondegradable additive compositions. Until now, data of ecotoxicity of BDP additives is scarce. Here, nematode C. elegans was used to comparatively evaluate toxicity of an isocyanate additive, i.e., Hexamethylene diisocyanate (HDI), a maleic anhydride, i.e., Diallyl maleate (DIM), and other four BDP organic additives. These additives caused lethality of nematodes at µg L-1 level, of lowest LC50 value of HDI/DIM. Uniform exposure to these additives resulted in various degrees of inhibitions in body volumes and longevity, indicating developmental toxicity. Moreover, BDP additives induced significant elevations of gst-4 expression, especially mean 123.54 %/234.29 % increase in HDI/DIM group, but reduced ges-1 expression, which indicates oxidative damages and mitochondrial dysfunction. BDP additives further caused inhibition in locomotor and food intake/excretion behavior, and related damages of glutamatergic neurons and GABAergic neurons, indicating their neurotoxicity. We found HDI and DIM presented relatively strong effects on susceptible endpoints including lethality, gst-4, mean lifespan, food intake and excretion behavior. Overall, this study suggests prominent ecotoxic risk of isocyanates and maleic anhydrides as BDP additives, which is significant for the selection of environmentally friendly BDP additives.
Collapse
Affiliation(s)
- Xinyu Li
- School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China
| | - Yingxin Chen
- School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China
| | - Wei Gao
- School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China; Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, East China Normal University, Shanghai 200241, China
| | - Aoyun Mo
- School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China
| | - Yalin Zhang
- School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China
| | - Jie Jiang
- School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China; Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, East China Normal University, Shanghai 200241, China
| | - Defu He
- School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China; Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, East China Normal University, Shanghai 200241, China; Shanghai Key Laboratory for Urban Ecological Processes and Eco-Restoration, East China Normal University, Shanghai 200241, China; Technology Innovation Center for Land Spatial Eco-restoration in Metropolitan Area, Ministry of Natural Resources, Shanghai 200062, China.
| |
Collapse
|
16
|
da Silva TC, da Silveira TL, Dos Santos LV, Arantes LP, Martins RP, Soares FAA, Dalla Corte CL. Exogenous Adenosine Modulates Behaviors and Stress Response in Caenorhabditis elegans. Neurochem Res 2023; 48:117-130. [PMID: 36018438 DOI: 10.1007/s11064-022-03727-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 07/14/2022] [Accepted: 08/15/2022] [Indexed: 01/11/2023]
Abstract
Adenosine, a purine nucleoside with neuromodulatory actions, is part of the purinergic signaling system (PSS). Caenorhabditis elegans is a free-living nematode found in soil, used in biological research for its advantages as an alternative experimental model. Since there is a lack of evidence of adenosine's direct actions and the PSS's participation in this animal, such an investigation is necessary. In this research, we aimed to test the effects of acute and chronic adenosine at 1, 5, and 10 mM on nematode's behaviors, morphology, survival after stress conditions, and on pathways related to the response to oxidative stress (DAF-16/FOXO and SKN-1) and genes products downstream these pathways (SOD-3, HSP-16.2, and GCS-1). Acute or chronic adenosine did not alter the worms' morphology analyzed by the worms' length, width, and area, nor interfered with reproductive behavior. On the other hand, acute and chronic adenosine modulated the defecation rate, pharyngeal pumping rate, and locomotion, in addition, to interacting with stress response pathways in C. elegans. Adenosine interfered in the speed and mobility of the worms analyzed. In addition, both acute and chronic adenosine presented modulatory effects on oxidative stress response signaling. Acute adenosine prevented the heat-induced-increase of DAF-16 activation and SOD-3 levels, while chronic adenosine per se induced DAF-16 activation and prevented heat-induced-increase of HSP-16.2 and SKN-1 levels. Together, these results indicate that exogenous adenosine has physiological and biochemical effects on C. elegans and describes possible purinergic signaling in worms.
Collapse
Affiliation(s)
- Thayanara Cruz da Silva
- Departamento de Bioquímica e Biologia Molecular, Programa de Pós-graduação em Ciências Biológicas: Bioquímica Toxicológica, Centro de Ciências Naturais e Exatas, Universidade Federal de Santa Maria, Av. Roraima nº 1000, Camobi, Santa Maria, RS, 97105-900, Brazil
| | - Tássia Limana da Silveira
- Departamento de Bioquímica e Biologia Molecular, Programa de Pós-graduação em Ciências Biológicas: Bioquímica Toxicológica, Centro de Ciências Naturais e Exatas, Universidade Federal de Santa Maria, Av. Roraima nº 1000, Camobi, Santa Maria, RS, 97105-900, Brazil
| | - Luiza Venturini Dos Santos
- Departamento de Bioquímica e Biologia Molecular, Programa de Pós-graduação em Ciências Biológicas: Bioquímica Toxicológica, Centro de Ciências Naturais e Exatas, Universidade Federal de Santa Maria, Av. Roraima nº 1000, Camobi, Santa Maria, RS, 97105-900, Brazil
| | - Leticia Priscila Arantes
- Instituto Latino-Americano de Ciências da Vida e da Natureza, Universidade Federal da Integração Latino-Americana, Foz do Iguaçu, Paraná, 85866-000, Brazil
| | - Rodrigo Pereira Martins
- Departamento de Bioquímica e Biologia Molecular, Programa de Pós-graduação em Ciências Biológicas: Bioquímica Toxicológica, Centro de Ciências Naturais e Exatas, Universidade Federal de Santa Maria, Av. Roraima nº 1000, Camobi, Santa Maria, RS, 97105-900, Brazil
| | - Félix Alexandre Antunes Soares
- Departamento de Bioquímica e Biologia Molecular, Programa de Pós-graduação em Ciências Biológicas: Bioquímica Toxicológica, Centro de Ciências Naturais e Exatas, Universidade Federal de Santa Maria, Av. Roraima nº 1000, Camobi, Santa Maria, RS, 97105-900, Brazil
| | - Cristiane Lenz Dalla Corte
- Departamento de Bioquímica e Biologia Molecular, Programa de Pós-graduação em Ciências Biológicas: Bioquímica Toxicológica, Centro de Ciências Naturais e Exatas, Universidade Federal de Santa Maria, Av. Roraima nº 1000, Camobi, Santa Maria, RS, 97105-900, Brazil.
| |
Collapse
|
17
|
JM-20 affects GABA neurotransmission in Caenorhabditis elegans. Neurotoxicology 2022; 93:37-44. [PMID: 36029931 DOI: 10.1016/j.neuro.2022.08.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 08/19/2022] [Accepted: 08/20/2022] [Indexed: 11/22/2022]
Abstract
Along with the discovery of new candidate molecules for pharmaceuticals, several studies have emerged showing different mechanisms of action and toxicological aspects. 3-ethoxycarbonyl-2-methyl-4- (2-nitrophenyl)4,11-dihydro-1H-pyrido [2,3-b] [1,5] benzodiazepine (JM-20) is a hybrid molecule. It is derived from 1,5-benzodiazepines and structurally differentiated by the addition of 1,4-dihydropyridine bonded to the benzodiazepine ring. This gives this molecule potential neuroprotective, antioxidant, and anxiolytic activity. As this is a promising multi-target molecule, further studies are necessary to improve the knowledge about its mechanism of action. In our study, we used Caenorhabditis elegans (C. elegans) to investigate the effects of chronic treatment with JM-20. Nematodes from the wild-type strain (N2) were treated chronically at different concentrations of JM-20. Our results show that JM-20 does not cause mortality, but higher concentrations can delay the development of worms after 48h exposure. We assessed basic behaviors in the worm, and our data demonstrate decreased defecation cycle. Our results suggest that JM-20 acts on the C. elegans GABAergic system because GABA neurotransmission is associated with the worm intestine. We also observed increased locomotor activity and decreased egg-laying after JM-20 treatment. When both behaviors were evaluated in mutants with have reduced levels of GABA (unc-25), this effect is no observed, suggesting the GABAergic modulation. Still, the JM-20 exert similar effect of Diazepam in basic behaviors observed. To reinforce neuromodulatory action, computational analysis was performed, and results showed a JM-20 binding on allosteric sites of nematodes GABA receptors. Overall, this work provided a better understanding of the effects of JM-20 in C. elegans as well as showed the effects of this new molecule on the GABAergic system in this animal model.
Collapse
|
18
|
Naraine AS, Aker R, Sweeney I, Kalvey M, Surtel A, Shanbhag V, Dawson-Scully K. Roundup and glyphosate's impact on GABA to elicit extended proconvulsant behavior in Caenorhabditis elegans. Sci Rep 2022; 12:13655. [PMID: 35999230 PMCID: PMC9399239 DOI: 10.1038/s41598-022-17537-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Accepted: 07/27/2022] [Indexed: 11/28/2022] Open
Abstract
As 3 billion pounds of herbicides are sprayed over farmlands every year, it is essential to advance our understanding how pesticides may influence neurological health and physiology of both humans and other animals. Studies are often one-dimensional as the majority examine glyphosate by itself. Farmers and the public use commercial products, like Roundup, containing a myriad of chemicals in addition to glyphosate. Currently, there are no neurological targets proposed for glyphosate and little comparison to Roundup. To investigate this, we compared how glyphosate and Roundup affect convulsant behavior in C.elegans and found that glyphosate and Roundup increased seizure-like behavior. Key to our initial hypothesis, we found that treatment with an antiepileptic drug rescued the prolonged convulsions. We also discovered over a third of nematodes exposed to Roundup did not recover from their convulsions, but drug treatment resulted in full recovery. Notably, these effects were found at concentrations that are 1,000-fold dilutions of previous findings of neurotoxicity, using over 300-fold less herbicide than the lowest concentration recommended for consumer use. Exploring mechanisms behind our observations, we found significant evidence that glyphosate targets GABA-A receptors. Pharmacological experiments which paired subeffective dosages of glyphosate and a GABA-A antagonist yielded a 24% increase in non-recovery compared to the antagonist alone. GABA mutant strain experiments showed no effect in a GABA-A depleted strain, but a significant, increased effect in a glutamic acid decarboxylase depleted strain. Our findings characterize glyphosate’s exacerbation of convulsions and propose the GABA-A receptor as a neurological target for the observed physiological changes. It also highlights glyphosate’s potential to dysregulate inhibitory neurological circuits.
Collapse
Affiliation(s)
- Akshay S Naraine
- Department of Biological Sciences, Florida Atlantic University, Boca Raton, FL, USA. .,IMPRS for Synapses and Circuits, Max Planck Florida Institute for Neuroscience, Jupiter, FL, USA.
| | - Rebecca Aker
- Department of Biological Sciences, Florida Atlantic University, Boca Raton, FL, USA
| | - Isis Sweeney
- Department of Biological Sciences, Florida Atlantic University, Boca Raton, FL, USA
| | - Meghan Kalvey
- Department of Biological Sciences, Florida Atlantic University, Boca Raton, FL, USA
| | - Alexis Surtel
- Department of Biological Sciences, Florida Atlantic University, Boca Raton, FL, USA
| | - Venkatesh Shanbhag
- Department of Chemistry and Physics, Halmos College of Arts and Sciences, Nova Southeastern University, Davie, FL, USA
| | - Ken Dawson-Scully
- Department of Biological Sciences, Florida Atlantic University, Boca Raton, FL, USA.,Department of Psychology and Neuroscience, College of Psychology, Nova Southeastern University, Davie, FL, USA
| |
Collapse
|
19
|
Invited review: Unearthing the mechanisms of age-related neurodegenerative disease using Caenorhabditis elegans. Comp Biochem Physiol A Mol Integr Physiol 2022; 267:111166. [PMID: 35176489 DOI: 10.1016/j.cbpa.2022.111166] [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: 12/17/2021] [Revised: 02/07/2022] [Accepted: 02/09/2022] [Indexed: 12/11/2022]
Abstract
As human life expectancy increases, neurodegenerative diseases present a growing public health threat, for which there are currently few effective treatments. There is an urgent need to understand the molecular and genetic underpinnings of these disorders so new therapeutic targets can be identified. Here we present the argument that the simple nematode worm Caenorhabditis elegans is a powerful tool to rapidly study neurodegenerative disorders due to their short lifespan and vast array of genetic tools, which can be combined with characterization of conserved neuronal processes and behavior orthologous to those disrupted in human disease. We review how pre-existing C. elegans models provide insight into human neurological disease as well as an overview of current tools available to study neurodegenerative diseases in the worm, with an emphasis on genetics and behavior. We also discuss open questions that C. elegans may be particularly well suited for in future studies and how worms will be a valuable preclinical model to better understand these devastating neurological disorders.
Collapse
|
20
|
Zaninello M, Palikaras K, Sotiriou A, Tavernarakis N, Scorrano L. Sustained intracellular calcium rise mediates neuronal mitophagy in models of autosomal dominant optic atrophy. Cell Death Differ 2022; 29:167-177. [PMID: 34389813 PMCID: PMC8738763 DOI: 10.1038/s41418-021-00847-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 07/23/2021] [Accepted: 07/27/2021] [Indexed: 02/07/2023] Open
Abstract
Mitochondrial dysfunction and mitophagy are often hallmarks of neurodegenerative diseases such as autosomal dominant optic atrophy (ADOA) caused by mutations in the key mitochondrial dynamics protein optic atrophy 1 (Opa1). However, the second messengers linking mitochondrial dysfunction to initiation of mitophagy remain poorly characterized. Here, we show in mammalian and nematode neurons that Opa1 mutations trigger Ca2+-dependent mitophagy. Deletion or expression of mutated Opa1 in mouse retinal ganglion cells and Caenorhabditis elegans motor neurons lead to mitochondrial dysfunction, increased cytosolic Ca2+ levels, and decreased axonal mitochondrial density. Chelation of Ca2+ restores mitochondrial density in neuronal processes, neuronal function, and viability. Mechanistically, sustained Ca2+ levels activate calcineurin and AMPK, placed in the same genetic pathway regulating axonal mitochondrial density. Our data reveal that mitophagy in ADOA depends on Ca2+-calcineurin-AMPK signaling cascade.
Collapse
Affiliation(s)
- Marta Zaninello
- grid.428736.cVeneto Institute of Molecular Medicine, Padova, Italy ,grid.5608.b0000 0004 1757 3470Department of Biology, University of Padova, Padova, Italy ,grid.6190.e0000 0000 8580 3777Present Address: Cologne Excellence Cluster on Cellular Stress Responses in Aging‐Associated Diseases (CECAD), University of Cologne, Cologne, Germany
| | - Konstantinos Palikaras
- grid.5216.00000 0001 2155 0800Department of Physiology, School of Medicine, National and Kapodistrian University of Athens, Athens, Greece
| | - Aggeliki Sotiriou
- grid.4834.b0000 0004 0635 685XInstitute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Heraklion, Crete Greece
| | - Nektarios Tavernarakis
- grid.4834.b0000 0004 0635 685XInstitute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Heraklion, Crete Greece ,grid.8127.c0000 0004 0576 3437Department of Basic Sciences, School of Medicine, University of Crete, Heraklion, Crete Greece
| | - Luca Scorrano
- grid.428736.cVeneto Institute of Molecular Medicine, Padova, Italy ,grid.5608.b0000 0004 1757 3470Department of Biology, University of Padova, Padova, Italy
| |
Collapse
|
21
|
Koopman M, Janssen L, Nollen EAA. An economical and highly adaptable optogenetics system for individual and population-level manipulation of Caenorhabditis elegans. BMC Biol 2021; 19:170. [PMID: 34429103 PMCID: PMC8386059 DOI: 10.1186/s12915-021-01085-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Accepted: 07/06/2021] [Indexed: 11/10/2022] Open
Abstract
Background Optogenetics allows the experimental manipulation of excitable cells by a light stimulus without the need for technically challenging and invasive procedures. The high degree of spatial, temporal, and intensity control that can be achieved with a light stimulus, combined with cell type-specific expression of light-sensitive ion channels, enables highly specific and precise stimulation of excitable cells. Optogenetic tools have therefore revolutionized the study of neuronal circuits in a number of models, including Caenorhabditis elegans. Despite the existence of several optogenetic systems that allow spatial and temporal photoactivation of light-sensitive actuators in C. elegans, their high costs and low flexibility have limited wide access to optogenetics. Here, we developed an inexpensive, easy-to-build, modular, and adjustable optogenetics device for use on different microscopes and worm trackers, which we called the OptoArm. Results The OptoArm allows for single- and multiple-worm illumination and is adaptable in terms of light intensity, lighting profiles, and light color. We demonstrate OptoArm’s power in a population-based multi-parameter study on the contributions of motor circuit cells to age-related motility decline. We found that individual components of the neuromuscular system display different rates of age-dependent deterioration. The functional decline of cholinergic neurons mirrors motor decline, while GABAergic neurons and muscle cells are relatively age-resilient, suggesting that rate-limiting cells exist and determine neuronal circuit ageing. Conclusion We have assembled an economical, reliable, and highly adaptable optogenetics system which can be deployed to address diverse biological questions. We provide a detailed description of the construction as well as technical and biological validation of our set-up. Importantly, use of the OptoArm is not limited to C. elegans and may benefit studies in multiple model organisms, making optogenetics more accessible to the broader research community. Supplementary Information The online version contains supplementary material available at 10.1186/s12915-021-01085-2.
Collapse
Affiliation(s)
- M Koopman
- European Research Institute for the Biology of Ageing, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
| | - L Janssen
- European Research Institute for the Biology of Ageing, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - E A A Nollen
- European Research Institute for the Biology of Ageing, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
| |
Collapse
|
22
|
Politi FAS, Bueno RV, Zeoly LA, Fantatto RR, Eloy JDO, Chorilli M, Coelho F, Guido RVC, Chagas ACDS, Furlan M. Anthelmintic activity of a nanoformulation based on thiophenes identified in Tagetes patula L. (Asteraceae) against the small ruminant nematode Haemonchus contortus. Acta Trop 2021; 219:105920. [PMID: 33861973 DOI: 10.1016/j.actatropica.2021.105920] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 02/02/2021] [Accepted: 04/07/2021] [Indexed: 11/25/2022]
Abstract
The synthesis of thiophenic compounds, previously identified in Tagetes patula, revealed that 4-(5'-(hydroxymethyl)-[2,2'-bithiophene]-5-yl)but-3-yn-1-ol), or simply Thio1, has a pronounced in vitro anthelmintic effect against Haemonchus contortus, showing 100% efficacy in the egg hatch and larval development tests presenting EC50 = 0.1731 mg.mL-1 and EC50 = 0.3243 mg.mL-1, respectively. So, this compound was selected to preparation of a nanostructured formulation to be orally administered to Santa Inês sheep. In general, from the fecal egg count reduction test (FECRT), it was observed that the product kept the parasitic load in the digestive tract of the hosts stable, with eggs per gram of faeces (EPG) counts having a mean value < 3,000 (EPGmean = 2167.1, efficacy = 36,45%), thus protecting the animals from health risks caused by a massive nematode infestation. To better understand the mode of action of this thiophene derivative, in silico molecular modeling studies were carried out with the glutamate-activated chloride channel (GluCl), a well-known molecular target of anthelmintic compounds. Based on the affinity score (GlideScore = -5.7 kcal.mol-1) and the proposed binding mode, Thio1 could be classified as a potential GluCl ligand, justifying the promising results observed in the anthelmintic assays.
Collapse
|
23
|
Zhang W, Li W, Li J, Chang X, Niu S, Wu T, Kong L, Zhang T, Tang M, Xue Y. Neurobehavior and neuron damage following prolonged exposure of silver nanoparticles with/without polyvinylpyrrolidone coating in Caenorhabditis elegans. J Appl Toxicol 2021; 41:2055-2067. [PMID: 33993517 DOI: 10.1002/jat.4197] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 04/15/2021] [Accepted: 05/01/2021] [Indexed: 12/18/2022]
Abstract
Silver nanoparticles (AgNPs) have become widespread in the environment with increasing industrial applications. But the studies about their potential health risks are far from enough, especially in neurotoxic effects. This study aimed to investigate the neurotoxic effects of longer-term exposure (prolonged exposure for 48 h and chronic exposure for 6 days) of 20nm AgNPs with/without polyvinylpyrrolidone (PVP) coating at low concentrations (0.01-10 mg·L-1 ) to Caenorhabditis elegans. The results suggested that exposure to AgNPs induced damage to nematode survival, with the longest and relative average life span reduced. Exposure to AgNPs caused neurotoxicity on locomotion behaviors (head thrashes, body bends, pharyngeal pumping frequency, and defecation interval) and sensory perception behaviors (chemotaxis assay and thermotaxis assay), as well as impaired dopaminergic, GABAergic, and cholinergic neurons, except for glutamatergic, based on the alters fluorescence intensity, in a dose- and time-dependent manner. Further investigations suggested that the low-dose AgNPs (0.01-0.1 mg·L-1 ) exposure raises receptors of GABAergic and dopamine in C. elegans at the genetic level, whereas opposite results were observed at higher doses (1-10 mg·L-1 ), which implied that AgNPs could cause neurotoxicity by impairing neurotransmitter delivery. The PVP-AgNPs could cause a higher fatality rate and neurotoxicity at the same dose. Notably, AgNPs did not cause any deleterious effect on nematodes at the lowest dose of 0.01 mg·L-1 . In general, these results suggested that AgNPs possess the neurotoxic potential in C. elegans and provided useful information to understand the neurotoxicity of AgNPs, which would offer an inspiring perspective on the safe application.
Collapse
Affiliation(s)
- Wenli Zhang
- Key Laboratory of Environmental Medicine and Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing, China
| | - Wenhua Li
- Key Laboratory of Environmental Medicine and Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing, China
| | - Jiangyan Li
- Key Laboratory of Environmental Medicine and Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing, China
| | - Xiaoru Chang
- Key Laboratory of Environmental Medicine and Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing, China
| | - Shuyan Niu
- Key Laboratory of Environmental Medicine and Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing, China
| | - Tianshu Wu
- Key Laboratory of Environmental Medicine and Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing, China
| | - Lu Kong
- Key Laboratory of Environmental Medicine and Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing, China
| | - Ting Zhang
- Key Laboratory of Environmental Medicine and Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing, China
| | - Meng Tang
- Key Laboratory of Environmental Medicine and Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing, China
| | - Yuying Xue
- Key Laboratory of Environmental Medicine and Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing, China
| |
Collapse
|
24
|
GABAergic synapses suppress intestinal innate immunity via insulin signaling in Caenorhabditis elegans. Proc Natl Acad Sci U S A 2021; 118:2021063118. [PMID: 33972423 DOI: 10.1073/pnas.2021063118] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
GABAergic neurotransmission constitutes a major inhibitory signaling mechanism that plays crucial roles in central nervous system physiology and immune cell immunomodulation. However, its roles in innate immunity remain unclear. Here, we report that deficiency in the GABAergic neuromuscular junctions (NMJs) of Caenorhabditis elegans results in enhanced resistance to pathogens, whereas pathogen infection enhances the strength of GABAergic transmission. GABAergic synapses control innate immunity in a manner dependent on the FOXO/DAF-16 but not the p38/PMK-1 pathway. Our data reveal that the insulin-like peptide INS-31 level was dramatically decreased in the GABAergic NMJ GABAAR-deficient unc-49 mutant compared with wild-type animals. C. elegans with ins-31 knockdown or loss of function exhibited enhanced resistance to Pseudomonas aeruginosa PA14 exposure. INS-31 may act downstream of GABAergic NMJs and in body wall muscle to control intestinal innate immunity in a cell-nonautonomous manner. Our results reveal a signaling axis of synapse-muscular insulin-intestinal innate immunity in vivo.
Collapse
|
25
|
Inhibition Underlies Fast Undulatory Locomotion in Caenorhabditis elegans. eNeuro 2021; 8:ENEURO.0241-20.2020. [PMID: 33361147 PMCID: PMC7986531 DOI: 10.1523/eneuro.0241-20.2020] [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: 06/08/2020] [Revised: 10/20/2020] [Accepted: 12/01/2020] [Indexed: 12/21/2022] Open
Abstract
Inhibition plays important roles in modulating the neural activities of sensory and motor systems at different levels from synapses to brain regions. To achieve coordinated movement, motor systems produce alternating contractions of antagonist muscles, whether along the body axis or within and among limbs, which often involves direct or indirect cross-inhibitory pathways. In the nematode Caenorhabditis elegans, a small network involving excitatory cholinergic and inhibitory GABAergic motoneurons generates the dorsoventral alternation of body-wall muscles that supports undulatory locomotion. Inhibition has been suggested to be necessary for backward undulation because mutants that are defective in GABA transmission exhibit a shrinking phenotype in response to a harsh touch to the head, whereas wild-type animals produce a backward escape response. Here, we demonstrate that the shrinking phenotype is exhibited by wild-type as well as mutant animals in response to harsh touch to the head or tail, but only GABA transmission mutants show slow locomotion after stimulation. Impairment of GABA transmission, either genetically or optogenetically, induces lower undulation frequency and lower translocation speed during crawling and swimming in both directions. The activity patterns of GABAergic motoneurons are different during low-frequency and high-frequency undulation. During low-frequency undulation, GABAergic VD and DD motoneurons show correlated activity patterns, while during high-frequency undulation, their activity alternates. The experimental results suggest at least three non-mutually exclusive roles for inhibition that could underlie fast undulatory locomotion in C. elegans, which we tested with computational models: cross-inhibition or disinhibition of body-wall muscles, or neuronal reset.
Collapse
|
26
|
Bowles SN, Johnson CM. Inferences of glia-mediated control in Caenorhabditis elegans. J Neurosci Res 2021; 99:1191-1206. [PMID: 33559247 DOI: 10.1002/jnr.24803] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Accepted: 01/12/2021] [Indexed: 12/22/2022]
Abstract
Astrocytes modulate synaptic transmission; yet, it remains unclear how glia influence complex behaviors. Here, we explore the effects of Caenorhabditis elegans astrocyte-like cephalic glia (CEPglia ) and the glia-specific bHLH transcription factor HLH-17 on mating behavior and the defecation motor program (DMP). In C. elegans, male mating has been explicitly described through the male tail circuit and is characterized by coordination of multiple independent behaviors to ensure that copulation is achieved. Furthermore, the sex-specific male mating circuitry shares similar components with the DMP, which is complex and rhythmic, and requires a fixed sequence of behaviors to be activated periodically. We found that loss of CEPglia reduced persistence in executing mating behaviors and hindered copulation, while males that lacked HLH-17 demonstrated repetitive prodding behavior that increased the time spent in mating but did not hinder copulation. During the DMP, we found that posterior body wall contractions (pBocs) and enteric muscle contractions (EMCs) were differentially affected by loss of HLH-17 or CEPglia in males and hermaphrodites. pBocs and EMCs required HLH-17 activity in both sexes, whereas loss of CEPglia alone did not affect DMP in males. Our data suggest that CEPglia mediate complex behaviors by signaling to the GABAergic DVB neuron, and that HLH-17 activity influences those discrete steps within those behaviors. Collectively, these data provide evidence of glia as a link in cooperative regulation of complex and rhythmic behavior that, in C. elegans links circuitry in the head and the tail.
Collapse
Affiliation(s)
| | - Casonya M Johnson
- Department of Biology, Georgia State University, Atlanta, GA, USA.,Department of Biology, James Madison University, Harrisonburg, VA, USA
| |
Collapse
|
27
|
Tsuchiya R, Kaneshima A, Kobayashi M, Yamazaki M, Takasu Y, Sezutsu H, Tanaka Y, Mizoguchi A, Shiomi K. Maternal GABAergic and GnRH/corazonin pathway modulates egg diapause phenotype of the silkworm Bombyx mori. Proc Natl Acad Sci U S A 2021; 118:e2020028118. [PMID: 33443213 PMCID: PMC7817158 DOI: 10.1073/pnas.2020028118] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Diapause represents a major developmental switch in insects and is a seasonal adaptation that evolved as a specific subtype of dormancy in most insect species to ensure survival under unfavorable environmental conditions and synchronize populations. However, the hierarchical relationship of the molecular mechanisms involved in the perception of environmental signals to integration in morphological, physiological, behavioral, and reproductive responses remains unclear. In the bivoltine strain of the silkworm Bombyx mori, embryonic diapause is induced transgenerationally as a maternal effect. Progeny diapause is determined by the environmental temperature during embryonic development of the mother. Here, we show that the hierarchical pathway consists of a γ-aminobutyric acid (GABA)ergic and corazonin signaling system modulating progeny diapause induction via diapause hormone release, which may be finely tuned by the temperature-dependent expression of plasma membrane GABA transporter. Furthermore, this signaling pathway possesses similar features to the gonadotropin-releasing hormone (GnRH) signaling system for seasonal reproductive plasticity in vertebrates.
Collapse
Affiliation(s)
- Ryoma Tsuchiya
- Faculty of Textile Science and Technology, Shinshu University, Ueda 386-8567, Japan
| | - Aino Kaneshima
- Faculty of Textile Science and Technology, Shinshu University, Ueda 386-8567, Japan
| | - Masakazu Kobayashi
- Faculty of Textile Science and Technology, Shinshu University, Ueda 386-8567, Japan
| | - Maki Yamazaki
- Faculty of Textile Science and Technology, Shinshu University, Ueda 386-8567, Japan
| | - Yoko Takasu
- National Agriculture and Food Research Organization, 305-8634 Tsukuba, Japan
| | - Hideki Sezutsu
- National Agriculture and Food Research Organization, 305-8634 Tsukuba, Japan
| | - Yoshiaki Tanaka
- National Agriculture and Food Research Organization, 305-8634 Tsukuba, Japan
| | - Akira Mizoguchi
- Division of Liberal Arts and Sciences, Aichi Gakuin University, Nisshin 470-0195, Japan
| | - Kunihiro Shiomi
- Faculty of Textile Science and Technology, Shinshu University, Ueda 386-8567, Japan;
| |
Collapse
|
28
|
Abstract
Melatonin (Mel) promotes sleep through G protein-coupled receptors. However, the downstream molecular target(s) is unknown. We identified the Caenorhabditis elegans BK channel SLO-1 as a molecular target of the Mel receptor PCDR-1-. Knockout of pcdr-1, slo-1, or homt-1 (a gene required for Mel synthesis) causes substantially increased neurotransmitter release and shortened sleep duration, and these effects are nonadditive in double knockouts. Exogenous Mel inhibits neurotransmitter release and promotes sleep in wild-type (WT) but not pcdr-1 and slo-1 mutants. In a heterologous expression system, Mel activates the human BK channel (hSlo1) in a membrane-delimited manner in the presence of the Mel receptor MT1 but not MT2 A peptide acting to release free Gβγ also activates hSlo1 in a MT1-dependent and membrane-delimited manner, whereas a Gβλ inhibitor abolishes the stimulating effect of Mel. Our results suggest that Mel promotes sleep by activating the BK channel through a specific Mel receptor and Gβλ.
Collapse
|
29
|
Cuentas-Condori A, Miller Rd DM. Synaptic remodeling, lessons from C. elegans. J Neurogenet 2020; 34:307-322. [PMID: 32808848 PMCID: PMC7855814 DOI: 10.1080/01677063.2020.1802725] [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: 04/11/2020] [Accepted: 07/07/2020] [Indexed: 02/08/2023]
Abstract
Sydney Brenner's choice of Caenorhabditis elegans as a model organism for understanding the nervous system has accelerated discoveries of gene function in neural circuit development and behavior. In this review, we discuss a striking example of synaptic remodeling in the C. elegans motor circuit in which DD class motor neurons effectively reverse polarity as presynaptic and postsynaptic domains at opposite ends of the DD neurite switch locations. Originally revealed by EM reconstruction conducted over 40 years ago, DD remodeling has since been investigated by live cell imaging methods that exploit the power of C. elegans genetics to reveal key effectors of synaptic plasticity. Although synapses are also extensively rewired in developing mammalian circuits, the underlying remodeling mechanisms are largely unknown. Here, we highlight the possibility that studies in C. elegans can reveal pathways that orchestrate synaptic remodeling in more complex organisms. Specifically, we describe (1) transcription factors that regulate DD remodeling, (2) the cellular and molecular cascades that drive synaptic remodeling and (3) examples of circuit modifications in vertebrate neurons that share some similarities with synaptic remodeling in C. elegans DD neurons.
Collapse
|
30
|
Abay-Nørgaard S, Attianese B, Boreggio L, Salcini AE. Regulators of H3K4 methylation mutated in neurodevelopmental disorders control axon guidance in Caenorhabditis elegans. Development 2020; 147:dev.190637. [PMID: 32675280 PMCID: PMC7420840 DOI: 10.1242/dev.190637] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Accepted: 07/10/2020] [Indexed: 12/11/2022]
Abstract
Post-translational histone modifications regulate chromatin compaction and gene expression to control many aspects of development. Mutations in genes encoding regulators of H3K4 methylation are causally associated with neurodevelopmental disorders characterized by intellectual disability and deficits in motor functions. However, it remains unclear how H3K4 methylation influences nervous system development and contributes to the aetiology of disease. Here, we show that the catalytic activity of set-2, the Caenorhabditis elegans homologue of the H3K4 methyltransferase KMT2F/G (SETD1A/B) genes, controls embryonic transcription of neuronal genes and is required for establishing proper axon guidance, and for neuronal functions related to locomotion and learning. Moreover, we uncover a striking correlation between components of the H3K4 regulatory machinery mutated in neurodevelopmental disorders and the process of axon guidance in C. elegans. Thus, our study supports an epigenetic-based model for the aetiology of neurodevelopmental disorders, based on an aberrant axon guidance process originating from deregulated H3K4 methylation. Summary: Analysis of mutants lacking many known H3K4 regulators reveals the role of H3K4 methylation in C. elegans neuronal functions and suggests that aberrant axon guidance is a shared trait in neurodevelopmental diseases.
Collapse
Affiliation(s)
- Steffen Abay-Nørgaard
- BRIC, University of Copenhagen, Biotech Research and Innovation Centre, Ole Maaloes vej 5, 2200, Copenhagen, Denmark
| | - Benedetta Attianese
- BRIC, University of Copenhagen, Biotech Research and Innovation Centre, Ole Maaloes vej 5, 2200, Copenhagen, Denmark
| | - Laura Boreggio
- BRIC, University of Copenhagen, Biotech Research and Innovation Centre, Ole Maaloes vej 5, 2200, Copenhagen, Denmark
| | - Anna Elisabetta Salcini
- BRIC, University of Copenhagen, Biotech Research and Innovation Centre, Ole Maaloes vej 5, 2200, Copenhagen, Denmark
| |
Collapse
|
31
|
Talla V, Pierce AA, Adams KL, de Man TJB, Nallu S, Villablanca FX, Kronforst MR, de Roode JC. Genomic evidence for gene flow between monarchs with divergent migratory phenotypes and flight performance. Mol Ecol 2020; 29:2567-2582. [PMID: 32542770 DOI: 10.1111/mec.15508] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 06/05/2020] [Indexed: 12/24/2022]
Abstract
Monarch butterflies are known for their spectacular annual migration in eastern North America, with millions of monarchs flying up to 4,500 km to overwintering sites in central Mexico. Monarchs also live west of the Rocky Mountains, where they travel shorter distances to overwinter along the Pacific Coast. It is often assumed that eastern and western monarchs form distinct evolutionary units, but genomic studies to support this notion are lacking. We used a tethered flight mill to show that migratory eastern monarchs have greater flight performance than western monarchs, consistent with their greater migratory distances. However, analysing more than 20 million SNPs in 43 monarch genomes, we found no evidence for genomic differentiation between eastern and western monarchs. Genomic analysis also showed identical and low levels of genetic diversity, and demographic analyses indicated similar effective population sizes and ongoing gene flow between eastern and western monarchs. Gene expression analysis of a subset of candidate genes during active flight revealed differential gene expression related to nonmuscular motor activity. Our results demonstrate that eastern and western monarchs maintain migratory differences despite ongoing gene flow, and suggest that migratory differences between eastern and western monarchs are not driven by select major-effects alleles. Instead, variation in migratory distance and destination may be driven by environmentally induced differential gene expression or by many alleles of small effect.
Collapse
Affiliation(s)
- Venkat Talla
- Department of Biology, Emory University, Atlanta, GA, USA
| | | | - Kandis L Adams
- Department of Biology, Emory University, Atlanta, GA, USA
| | - Tom J B de Man
- Department of Biology, Emory University, Atlanta, GA, USA
| | - Sumitha Nallu
- Department of Ecology and Evolution, University of Chicago, Chicago, IL, USA
| | - Francis X Villablanca
- Biological Sciences Department, California Polytechnic State University, San Luis Obispo, CA, USA
| | - Marcus R Kronforst
- Department of Ecology and Evolution, University of Chicago, Chicago, IL, USA
| | | |
Collapse
|
32
|
Téllez-Arreola JL, Silva M, Martínez-Torres A. MCTP-1 modulates neurotransmitter release in C. elegans. Mol Cell Neurosci 2020; 107:103528. [PMID: 32650044 DOI: 10.1016/j.mcn.2020.103528] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 06/17/2020] [Accepted: 06/23/2020] [Indexed: 11/30/2022] Open
Abstract
Multiple C2 and Transmembrane Domain Proteins (MCTPs) are putative calcium sensors. Proteins that contain C2 domains play essential roles in membrane trafficking and exocytosis; however, MCTPs functions in neurotransmitter release are not known. Here we report that in C. elegans mctp-1 is under the control of two promoters - one active in the nervous system and the second in the spermatheca. We generated and characterized a loss of function amt1 mutant and compared it to a previously published loss of function mutant (av112). Loss of mctp-1 function causes defects in egg-laying, crawling velocity, and thrashing rates. Both amt1 and av112 mutants are hyposensitive to the acetylcholinesterase blocker aldicarb, suggesting that MCTP-1 may play a role in synaptic vesicle release.
Collapse
Affiliation(s)
- José Luis Téllez-Arreola
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Campus Juriquilla, Boulevard Juriquilla 3001, C.P. 76215 Juriquilla, Querétaro, México; School of Biological Sciences, University of Utah, Salt Lake City, United States
| | - Malan Silva
- School of Biological Sciences, University of Utah, Salt Lake City, United States
| | - Ataúlfo Martínez-Torres
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Campus Juriquilla, Boulevard Juriquilla 3001, C.P. 76215 Juriquilla, Querétaro, México.
| |
Collapse
|
33
|
Zahran F, Ezz El-Din HM, Shehata MAS. Study on the effect of an ion channel inhibitor "Fluralaner" on Echinococcus granulosus protoscolices and metacestode layers in vitro. J Parasit Dis 2020; 44:411-419. [PMID: 32508416 DOI: 10.1007/s12639-020-01224-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Accepted: 04/12/2020] [Indexed: 02/05/2023] Open
Abstract
Hydatid disease has a great impact on public health, causing high morbidity and mortality. Main lines of treatment include surgery, which mostly requires the installation of a scolicidal agent into hydatid cysts to prevent dissemination. Alternatively, medical treatment involves the use of benzimidazole drugs; however, the results are not satisfactory, and new drug compounds are urgently needed. Fluralaner is a potent inhibitor of GABA-gated chloride channels and L-glutamate-gated chloride channels (GluCls) providing immediate and persistent flea, tick and mite control in dogs after a single oral dose. Researches previously identified different genes encoding ion channels in Echinococcus granulosus, making ion channel inhibitors a promising target for treating hydatid disease. Thus, the present study aimed to evaluate the effect of fluralaner on protoscolices and metacestode layers. Parasite materials (Protoscolices, Metacestodes layers) were exposed to different concentrations of the drug ranging from "12.5-100 ug/ml" and examined for viability after 1, 6 and 24 h. Morphological and ultrastructural alterations were recorded by both light and electron microscopies. Immunohistochemical staining confirmed caspase-3 activation as an indicator of apoptosis- induced therapy. The treated protoscolices and metacestode layers showed loss of the viability, the formation of vacuoles and lipid droplets, separation of the germinal layer, and damage in the laminated layer; apoptosis was prominent after treatment. These findings revealed that fluralaner has a potent scolicidal activity and suggested its therapeutic potential against hydatid disease. Further evaluations for animals and human use in the treatment and prevention of hydatid disease are needed.
Collapse
Affiliation(s)
- Fatima Zahran
- Faculty of Medicine, Ain-Shams University, Ramsis St., Abbassia, Cairo, 11591 Egypt
| | | | | |
Collapse
|
34
|
Rudich P, Watkins S, Lamitina T. PolyQ-independent toxicity associated with novel translational products from CAG repeat expansions. PLoS One 2020; 15:e0227464. [PMID: 32240172 PMCID: PMC7117740 DOI: 10.1371/journal.pone.0227464] [Citation(s) in RCA: 9] [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: 12/16/2019] [Accepted: 03/11/2020] [Indexed: 02/08/2023] Open
Abstract
Expanded CAG nucleotide repeats are the underlying genetic cause of at least 14 incurable diseases, including Huntington’s disease (HD). The toxicity associated with many CAG repeat expansions is thought to be due to the translation of the CAG repeat to create a polyQ protein, which forms toxic oligomers and aggregates. However, recent studies show that HD CAG repeats undergo a non-canonical form of translation called Repeat-associated non-AUG dependent (RAN) translation. RAN translation of the CAG sense and CUG anti-sense RNAs produces six distinct repeat peptides: polyalanine (polyAla, from both CAG and CUG repeats), polyserine (polySer), polyleucine (polyLeu), polycysteine (polyCys), and polyglutamine (polyGln). The toxic potential of individual CAG-derived RAN polypeptides is not well understood. We developed pure C. elegans protein models for each CAG RAN polypeptide using codon-varied expression constructs that preserve RAN protein sequence but eliminate repetitive CAG/CUG RNA. While all RAN polypeptides formed aggregates, only polyLeu was consistently toxic across multiple cell types. In GABAergic neurons, which exhibit significant neurodegeneration in HD patients, codon-varied (Leu)38, but not (Gln)38, caused substantial neurodegeneration and motility defects. Our studies provide the first in vivo evaluation of CAG-derived RAN polypeptides in a multicellular model organism and suggest that polyQ-independent mechanisms, such as RAN-translated polyLeu peptides, may have a significant pathological role in CAG repeat expansion disorders.
Collapse
Affiliation(s)
- Paige Rudich
- Graduate Program in Cell Biology and Molecular Physiology, University of Pittsburgh Medical Center, Pittsburgh, PA, United States of America
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States of America
| | - Simon Watkins
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States of America
- Center for Biologic Imaging, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States of America
| | - Todd Lamitina
- Graduate Program in Cell Biology and Molecular Physiology, University of Pittsburgh Medical Center, Pittsburgh, PA, United States of America
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States of America
- Division of Child Neurology, Department of Pediatrics, Children’s Hospital of Pittsburgh, University of Pittsburgh Medical Center, Pittsburgh, PA, United States of America
- * E-mail:
| |
Collapse
|
35
|
Zhou X, Bessereau JL. Molecular Architecture of Genetically-Tractable GABA Synapses in C. elegans. Front Mol Neurosci 2019; 12:304. [PMID: 31920535 PMCID: PMC6920096 DOI: 10.3389/fnmol.2019.00304] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Accepted: 11/26/2019] [Indexed: 12/18/2022] Open
Abstract
Inhibitory synapses represent a minority of the total chemical synapses in the mammalian brain, yet proper tuning of inhibition is fundamental to shape neuronal network properties. The neurotransmitter γ-aminobutyric acid (GABA) mediates rapid synaptic inhibition by the activation of the type A GABA receptor (GABAAR), a pentameric chloride channel that governs major inhibitory neuronal transduction in the nervous system. Impaired GABA transmission leads to a variety of neuropsychiatric diseases, including schizophrenia, autism, epilepsy or anxiety. From an evolutionary perspective, GABAAR shows remarkable conservations, and are found in all eukaryotic clades and even in bacteria and archaea. Specifically, bona fide GABAARs are found in the nematode Caenorhabditis elegans. Because of the anatomical simplicity of the nervous system and its amenability to genetic manipulations, C. elegans provide a powerful system to investigate the molecular and cellular biology of GABA synapses. In this mini review article, we will introduce the structure of the C. elegans GABAergic system and describe recent advances that have identified novel proteins controlling the localization of GABAARs at synapses. In particular, Ce-Punctin/MADD-4 is an evolutionarily-conserved extracellular matrix protein that behaves as an anterograde synaptic organizer to instruct the excitatory or inhibitory identity of postsynaptic domains.
Collapse
Affiliation(s)
- Xin Zhou
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS UMR 5310, INSERM U 1217, Institut NeuroMyoGène, Lyon, France
| | - Jean-Louis Bessereau
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS UMR 5310, INSERM U 1217, Institut NeuroMyoGène, Lyon, France
| |
Collapse
|
36
|
Murray SM, Waddell BM, Wu CW. Neuron-specific toxicity of chronic acrylamide exposure in C. elegans. Neurotoxicol Teratol 2019; 77:106848. [PMID: 31756371 DOI: 10.1016/j.ntt.2019.106848] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 11/15/2019] [Accepted: 11/16/2019] [Indexed: 01/04/2023]
Abstract
Acrylamide is a food-borne chemical with well-known neurotoxic properties. To date, the toxicity mechanisms of chronic acrylamide exposure are not fully understood. Using the genetic model Caenorhabditis elegans, we found that chronic acrylamide exposure induces a locomotor defect that is characterized by severe uncoordination of muscle movement that is distinct from an overall reduction in activity. C. elegans exhibiting chronic acrylamide-induced locomotor defects show significant degeneration to the dopaminergic and cholinergic, but not GABAergic motor neurons. Degeneration of the dopaminergic and cholinergic neurons are found in 58% to 67% of C. elegans after chronic acrylamide exposure, with the varying degrees of severity ranging from neuronal blebbing to complete dendrite loss. The observed pattern of neurotoxicity does not have a heritable effect, as parental exposure to chronic acrylamide does not lead to neurodegeneration in the developed offspring. Overall, these finding illustrate that chronic acrylamide exposure cause locomotor defects by inducing degeneration of specific neuron types in C. elegans.
Collapse
Affiliation(s)
- Sydney M Murray
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, 52 Campus Drive, University of Saskatchewan, SK S7N 5B4, Canada; Toxicology Centre, University of Saskatchewan, Saskatoon, SK S7N 5B3, Canada
| | - Brandon M Waddell
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, 52 Campus Drive, University of Saskatchewan, SK S7N 5B4, Canada
| | - Cheng-Wei Wu
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, 52 Campus Drive, University of Saskatchewan, SK S7N 5B4, Canada; Toxicology Centre, University of Saskatchewan, Saskatoon, SK S7N 5B3, Canada.
| |
Collapse
|
37
|
Câmara DF, Machado ML, Arantes LP, Silva TC, Silveira TL, Leal JG, Dornelles L, Stefanello ST, Soares FAA. MPMT-OX up-regulates GABAergic transmission and protects against seizure-like behavior in Caenorhabditis elegans. Neurotoxicology 2019; 74:272-281. [PMID: 31415799 DOI: 10.1016/j.neuro.2019.08.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Revised: 08/02/2019] [Accepted: 08/02/2019] [Indexed: 11/17/2022]
Abstract
The signal transmission in the nervous system operates through a sensitive balance between excitatory (E) inputs and inhibitory (I) responses. Imbalances in this system contribute to the development of pathologies such as seizures. In Caenorhabditis elegans, the locomotor circuit operates via the coordinated activity of cholinergic excitatory (E) and GABAergic inhibitory (I) transmission. Changes in E/I inputs can cause uncontrolled electrical discharges, mimicking the physiology of seizures. Molecules derived from 1,3,4-oxadiazole have been found to exhibit diverse biological activities, including anticonvulsant effect. In this work, we study the activity of the compound 2-[(4-methoxyphenylselenyl)methylthio]-5-phenyl-1,3,4-oxadiazole (MPMT-OX) in the GABAergic and cholinergic systems. We demonstrate that MPMT-OX reduced the locomotor activity of C. elegans with a normal balance between the E/I systems and increased the resistance to paralysis in worms exposed to pentylenetetrazol and aldicarb. MPMT-OX increased seizure resistance and assisted in the recovery of locomotor activity in worms with deletions in the genes unc-46, which regulates the transport of GABA into vesicles, and unc-49, which encodes the GABAA receptor. C. elegans with deletions in the unc-25 and unc-47 genes did not respond to treatment. Therefore, we suggest that the compound MPMT-OX upregulates GABAergic signaling in a manner dependent on the unc-25 gene, which is responsible for GABA synthesis, and unc-47, which encodes the vesicular GABA transporter.
Collapse
Affiliation(s)
- Daniela F Câmara
- Departamento de Bioquímica e Biologia Molecular, CCNE, Universidade Federal de Santa Maria, CEP 97.105-900 Santa Maria, RS, Brazil
| | - Marina L Machado
- Departamento de Bioquímica e Biologia Molecular, CCNE, Universidade Federal de Santa Maria, CEP 97.105-900 Santa Maria, RS, Brazil
| | - Leticia P Arantes
- Departamento de Bioquímica e Biologia Molecular, CCNE, Universidade Federal de Santa Maria, CEP 97.105-900 Santa Maria, RS, Brazil
| | - Thayanara C Silva
- Departamento de Bioquímica e Biologia Molecular, CCNE, Universidade Federal de Santa Maria, CEP 97.105-900 Santa Maria, RS, Brazil
| | - Tássia L Silveira
- Departamento de Bioquímica e Biologia Molecular, CCNE, Universidade Federal de Santa Maria, CEP 97.105-900 Santa Maria, RS, Brazil
| | - Julliano G Leal
- Departamento de Bioquímica e Biologia Molecular, CCNE, Universidade Federal de Santa Maria, CEP 97.105-900 Santa Maria, RS, Brazil
| | - Luciano Dornelles
- Departamento de Bioquímica e Biologia Molecular, CCNE, Universidade Federal de Santa Maria, CEP 97.105-900 Santa Maria, RS, Brazil
| | - Sílvio T Stefanello
- Departamento de Bioquímica e Biologia Molecular, CCNE, Universidade Federal de Santa Maria, CEP 97.105-900 Santa Maria, RS, Brazil
| | - Félix A A Soares
- Departamento de Bioquímica e Biologia Molecular, CCNE, Universidade Federal de Santa Maria, CEP 97.105-900 Santa Maria, RS, Brazil.
| |
Collapse
|
38
|
Petrovic M, Bolton TAW, Preti MG, Liégeois R, Van De Ville D. Guided graph spectral embedding: Application to the C. elegans connectome. Netw Neurosci 2019; 3:807-826. [PMID: 31410381 PMCID: PMC6663470 DOI: 10.1162/netn_a_00084] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 03/12/2019] [Indexed: 11/17/2022] Open
Abstract
Graph spectral analysis can yield meaningful embeddings of graphs by providing insight into distributed features not directly accessible in nodal domain. Recent efforts in graph signal processing have proposed new decompositions—for example, based on wavelets and Slepians—that can be applied to filter signals defined on the graph. In this work, we take inspiration from these constructions to define a new guided spectral embedding that combines maximizing energy concentration with minimizing modified embedded distance for a given importance weighting of the nodes. We show that these optimization goals are intrinsically opposite, leading to a well-defined and stable spectral decomposition. The importance weighting allows us to put the focus on particular nodes and tune the trade-off between global and local effects. Following the derivation of our new optimization criterion, we exemplify the methodology on the C. elegans structural connectome. The results of our analyses confirm known observations on the nematode’s neural network in terms of functionality and importance of cells. Compared with Laplacian embedding, the guided approach, focused on a certain class of cells (sensory neurons, interneurons, or motoneurons), provides more biological insights, such as the distinction between somatic positions of cells, and their involvement in low- or high-order processing functions.
Collapse
Affiliation(s)
- Miljan Petrovic
- Institute of Bioengineering, École Polytechnique Fédérale de Lausanne, Campus Biotech, Geneva, Switzerland
| | - Thomas A W Bolton
- Institute of Bioengineering, École Polytechnique Fédérale de Lausanne, Campus Biotech, Geneva, Switzerland
| | - Maria Giulia Preti
- Institute of Bioengineering, École Polytechnique Fédérale de Lausanne, Campus Biotech, Geneva, Switzerland
| | - Raphaël Liégeois
- Institute of Bioengineering, École Polytechnique Fédérale de Lausanne, Campus Biotech, Geneva, Switzerland
| | - Dimitri Van De Ville
- Institute of Bioengineering, École Polytechnique Fédérale de Lausanne, Campus Biotech, Geneva, Switzerland
| |
Collapse
|
39
|
Giles AC, Desbois M, Opperman KJ, Tavora R, Maroni MJ, Grill B. A complex containing the O-GlcNAc transferase OGT-1 and the ubiquitin ligase EEL-1 regulates GABA neuron function. J Biol Chem 2019; 294:6843-6856. [PMID: 30858176 DOI: 10.1074/jbc.ra119.007406] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Revised: 03/07/2019] [Indexed: 12/16/2022] Open
Abstract
Inhibitory GABAergic transmission is required for proper circuit function in the nervous system. However, our understanding of molecular mechanisms that preferentially influence GABAergic transmission, particularly presynaptic mechanisms, remains limited. We previously reported that the ubiquitin ligase EEL-1 preferentially regulates GABAergic presynaptic transmission. To further explore how EEL-1 functions, here we performed affinity purification proteomics using Caenorhabditis elegans and identified the O-GlcNAc transferase OGT-1 as an EEL-1 binding protein. This observation was intriguing, as we know little about how OGT-1 affects neuron function. Using C. elegans biochemistry, we confirmed that the OGT-1/EEL-1 complex forms in neurons in vivo and showed that the human orthologs, OGT and HUWE1, also bind in cell culture. We observed that, like EEL-1, OGT-1 is expressed in GABAergic motor neurons, localizes to GABAergic presynaptic terminals, and functions cell-autonomously to regulate GABA neuron function. Results with catalytically inactive point mutants indicated that OGT-1 glycosyltransferase activity is dispensable for GABA neuron function. Consistent with OGT-1 and EEL-1 forming a complex, genetic results using automated, behavioral pharmacology assays showed that ogt-1 and eel-1 act in parallel to regulate GABA neuron function. These findings demonstrate that OGT-1 and EEL-1 form a conserved signaling complex and function together to affect GABA neuron function.
Collapse
Affiliation(s)
- Andrew C Giles
- From the Department of Neuroscience, The Scripps Research Institute, Scripps Florida, Jupiter, Florida 33458 and
| | - Muriel Desbois
- From the Department of Neuroscience, The Scripps Research Institute, Scripps Florida, Jupiter, Florida 33458 and
| | - Karla J Opperman
- From the Department of Neuroscience, The Scripps Research Institute, Scripps Florida, Jupiter, Florida 33458 and
| | - Rubens Tavora
- the Harriet L. Wilkes Honors College, Florida Atlantic University, Jupiter, Florida 33458
| | - Marissa J Maroni
- From the Department of Neuroscience, The Scripps Research Institute, Scripps Florida, Jupiter, Florida 33458 and
| | - Brock Grill
- From the Department of Neuroscience, The Scripps Research Institute, Scripps Florida, Jupiter, Florida 33458 and
| |
Collapse
|
40
|
Govindarajan D, Chatterjee C, Shakambari G, Varalakshmi P, Jayakumar K, Balasubramaniem A. Oxidative stress response, epigenetic and behavioral alterations in Caenorhabditis elegans exposed to organophosphorus pesticide quinalphos. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2019. [DOI: 10.1016/j.bcab.2019.01.031] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
|
41
|
Ding C, Hammarlund M. Aberrant information transfer interferes with functional axon regeneration. eLife 2018; 7:38829. [PMID: 30371349 PMCID: PMC6231761 DOI: 10.7554/elife.38829] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Accepted: 10/26/2018] [Indexed: 12/16/2022] Open
Abstract
Functional axon regeneration requires regenerating neurons to restore appropriate synaptic connectivity and circuit function. To model this process, we developed an assay in Caenorhabditis elegans that links axon and synapse regeneration of a single neuron to recovery of behavior. After axon injury and regeneration of the DA9 neuron, synapses reform at their pre-injury location. However, these regenerated synapses often lack key molecular components. Further, synaptic vesicles accumulate in the dendrite in response to axon injury. Dendritic vesicle release results in information misrouting that suppresses behavioral recovery. Dendritic synapse formation depends on dynein and jnk-1. But even when information transfer is corrected, axonal synapses fail to adequately transmit information. Our study reveals unexpected plasticity during functional regeneration. Regeneration of the axon is not sufficient for the reformation of correct neuronal circuits after injury. Rather, synapse reformation and function are also key variables, and manipulation of circuit reformation improves behavioral recovery.
Collapse
Affiliation(s)
- Chen Ding
- Department of Neuroscience, Yale University, New Haven, United States
| | - Marc Hammarlund
- Department of Neuroscience, Yale University, New Haven, United States.,Department of Genetics, Yale University, New Haven, United States
| |
Collapse
|
42
|
Knickelbine JJ, Konop CJ, Viola IR, Rogers CB, Messinger LA, Vestling MM, Stretton AOW. Different Bioactive Neuropeptides are Expressed in Two Sub-Classes of GABAergic RME Nerve Ring Motorneurons in Ascaris suum. ACS Chem Neurosci 2018; 9:2025-2040. [PMID: 29400437 DOI: 10.1021/acschemneuro.7b00450] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Neuropeptides can have significant effects on neurons and synapses, but among the ∼250 predicted peptides in nematodes, few have been characterized functionally. Here, we report new neuropeptides in the 4 RME nerve ring motorneurons of the nematode Ascaris suum. These GABAergic neurons are involved in three-dimensional head movement. Mass spectrometry (MS) of single dissected RMEs detected a total of 12 neuropeptides (encoded by five genes), nine of which are novel. None of these are expressed in the DI/VI inhibitory GABAergic motorneurons that synapse onto body wall muscle. Using peptide sequences obtained by tandem MS, we cloned the peptide-encoding transcripts and synthesized riboprobes for in situ hybridization (ISH). This complementary technique corroborated the results from single-cell MS, showing that the dissections were not contaminated with adhering tissue from other cells. We also synthesized a multiple antigenic peptide to raise a highly specific antibody against one of the endogenous peptides, which labeled the same cells detected by MS and ISH. Our results show that the RMEs can be divided into two subsets: RMED/V (expressing afp-2, afp-15, Asu-nlp-58, and high levels of afp-16) and RMEL/R (expressing afp-15 and low levels of afp-4 and afp-16). Almost all of these peptides are bioactive in A. suum.
Collapse
|
43
|
LIN-12/Notch Regulates GABA Signaling at the Caenorhabditis elegans Neuromuscular Junction. G3-GENES GENOMES GENETICS 2018; 8:2825-2832. [PMID: 29950427 PMCID: PMC6071610 DOI: 10.1534/g3.118.200202] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The role of Notch signaling in cell-fate decisions has been studied extensively; however, this pathway is also active in adult tissues, including the nervous system. Notch signaling modulates a wide range of behaviors and processes of the nervous system in the nematode Caenorhabditis elegans, but there is no evidence for Notch signaling directly altering synaptic strength. Here, we demonstrate Notch-mediated regulation of synaptic activity at the C. elegans neuromuscular junction (NMJ). For this, we used aldicarb, an inhibitor of the enzyme acetylcholinesterase, and assessed paralysis rates of animals with altered Notch signaling. Notch receptors LIN-12 and GLP-1 are required for normal NMJ function; they regulate NMJ activity in an opposing fashion. Complete loss of LIN-12 skews the excitation/inhibition balance at the NMJ toward increased activity, whereas partial loss of GLP-1 has the opposite effect. Specific Notch ligands and co-ligands are also required for proper NMJ function. The role of LIN-12 is independent of cell-fate decisions; manipulation of LIN-12 signaling through RNAi knockdown or overexpression of the co-ligand OSM-11 after development alters NMJ activity. We demonstrate that LIN-12 modulates GABA signaling in this paradigm, as loss of GABA signaling suppresses LIN-12 gain-of-function defects. Further analysis, in vivo and in silico, suggests that LIN-12 may modulate transcription of the GABAB receptor GBB-2 Our findings confirm a non-developmental role for the LIN-12/Notch receptor in regulating synaptic signaling and identify the GABAB receptor GBB-2 as a potential Notch transcriptional target in the C. elegans nervous system.
Collapse
|
44
|
Vieira N, Bessa C, Rodrigues AJ, Marques P, Chan FY, de Carvalho AX, Correia-Neves M, Sousa N. Sorting nexin 3 mutation impairs development and neuronal function in Caenorhabditis elegans. Cell Mol Life Sci 2018; 75:2027-2044. [PMID: 29196797 PMCID: PMC11105199 DOI: 10.1007/s00018-017-2719-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Revised: 10/27/2017] [Accepted: 11/22/2017] [Indexed: 02/07/2023]
Abstract
The sorting nexins family of proteins (SNXs) plays pleiotropic functions in protein trafficking and intracellular signaling and has been associated with several disorders, namely Alzheimer's disease and Down's syndrome. Despite the growing association of SNXs with neurodegeneration, not much is known about their function in the nervous system. The aim of this work was to use the nematode Caenorhabditis elegans that encodes in its genome eight SNXs orthologs, to dissect the role of distinct SNXs, particularly in the nervous system. By screening the C. elegans SNXs deletion mutants for morphological, developmental and behavioral alterations, we show here that snx-3 gene mutation leads to an array of developmental defects, such as delayed hatching, decreased brood size and life span and reduced body length. Additionally, ∆snx-3 worms present increased susceptibility to osmotic, thermo and oxidative stress and distinct behavioral deficits, namely, a chemotaxis defect which is independent of the described snx-3 role in Wnt secretion. ∆snx-3 animals also display abnormal GABAergic neuronal architecture and wiring and altered AIY interneuron structure. Pan-neuronal expression of C. elegans snx-3 cDNA in the ∆snx-3 mutant is able to rescue its locomotion defects, as well as its chemotaxis toward isoamyl alcohol. Altogether, the present work provides the first in vivo evidence of the SNX-3 role in the nervous system.
Collapse
Affiliation(s)
- Neide Vieira
- School of Medicine, Life and Health Sciences Research Institute (ICVS), University of Minho, Campus Gualtar, 4710-057, Braga, Portugal
- ICVS/3B's-PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Carlos Bessa
- School of Medicine, Life and Health Sciences Research Institute (ICVS), University of Minho, Campus Gualtar, 4710-057, Braga, Portugal
- ICVS/3B's-PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Ana J Rodrigues
- School of Medicine, Life and Health Sciences Research Institute (ICVS), University of Minho, Campus Gualtar, 4710-057, Braga, Portugal
- ICVS/3B's-PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Paulo Marques
- School of Medicine, Life and Health Sciences Research Institute (ICVS), University of Minho, Campus Gualtar, 4710-057, Braga, Portugal
- ICVS/3B's-PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Fung-Yi Chan
- i3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- Instituto de Biologia Molecular e Celular-IBMC, Porto, Portugal
| | - Ana Xavier de Carvalho
- i3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- Instituto de Biologia Molecular e Celular-IBMC, Porto, Portugal
| | - Margarida Correia-Neves
- School of Medicine, Life and Health Sciences Research Institute (ICVS), University of Minho, Campus Gualtar, 4710-057, Braga, Portugal
- ICVS/3B's-PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Nuno Sousa
- School of Medicine, Life and Health Sciences Research Institute (ICVS), University of Minho, Campus Gualtar, 4710-057, Braga, Portugal.
- ICVS/3B's-PT Government Associate Laboratory, Braga/Guimarães, Portugal.
| |
Collapse
|
45
|
Thapliyal S, Vasudevan A, Dong Y, Bai J, Koushika SP, Babu K. The C-terminal of CASY-1/Calsyntenin regulates GABAergic synaptic transmission at the Caenorhabditis elegans neuromuscular junction. PLoS Genet 2018. [PMID: 29529030 PMCID: PMC5864096 DOI: 10.1371/journal.pgen.1007263] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The C. elegans ortholog of mammalian calsyntenins, CASY-1, is an evolutionarily conserved type-I transmembrane protein that is highly enriched in the nervous system. Mammalian calsyntenins are strongly expressed at inhibitory synapses, but their role in synapse development and function is still elusive. Here, we report a crucial role for CASY-1 in regulating GABAergic synaptic transmission at the C. elegans neuromuscular junction (NMJ). The shorter isoforms of CASY-1; CASY-1B and CASY-1C, express and function in GABA motor neurons where they regulate GABA neurotransmission. Using pharmacological, behavioral, electrophysiological, optogenetic and imaging approaches we establish that GABA release is compromised at the NMJ in casy-1 mutants. Further, we demonstrate that CASY-1 is required to modulate the transport of GABAergic synaptic vesicle (SV) precursors through a possible interaction with the SV motor protein, UNC-104/KIF1A. This study proposes a possible evolutionarily conserved model for the regulation of GABA synaptic functioning by calsyntenins. GABA acts as a major inhibitory neurotransmitter in both vertebrate and invertebrate nervous systems. Despite the potential deregulation of GABA signaling in several neurological disorders, our understanding of the genetic factors that regulate GABAergic synaptic transmission has just started to evolve. Here, we identify a role for a cell adhesion molecule, CASY-1, in regulating GABA signaling at the C. elegans NMJ. We show that the mutants in casy-1 have reduced number of GABA vesicles at the synapse resulting in less GABA release from the presynaptic GABAergic motor neurons. Further, we show that the shorter isoforms of the casy-1 gene; casy-1b and casy-1c that carry a potential kinesin-motor binding domain are responsible for maintaining GABAergic signaling at the synapse. We show a novel interaction of the CASY-1 isoforms with the C- terminal of the UNC-104/KIF1A motor protein that mediates the trafficking of GABAergic synaptic vesicle precursors to the synapse, thus maintaining normal inhibitory signaling at the NMJ.
Collapse
Affiliation(s)
- Shruti Thapliyal
- Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Knowledge City, Sector 81, SAS Nagar, Manauli, Punjab, India
| | - Amruta Vasudevan
- Department of Biological Sciences, Tata Institute of Fundamental Research, Colaba, Mumbai, India
| | - Yongming Dong
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109 and Department of Biochemistry, University of Washington, Seattle, WA, United Sttaes of America
| | - Jihong Bai
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109 and Department of Biochemistry, University of Washington, Seattle, WA, United Sttaes of America
| | - Sandhya P. Koushika
- Department of Biological Sciences, Tata Institute of Fundamental Research, Colaba, Mumbai, India
| | - Kavita Babu
- Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Knowledge City, Sector 81, SAS Nagar, Manauli, Punjab, India
- * E-mail: ,
| |
Collapse
|
46
|
Abstract
BACKGROUND The microtubule-associated protein tau accumulates into toxic aggregates in multiple neurodegenerative diseases. We found previously that loss of D2-family dopamine receptors ameliorated tauopathy in multiple models including a Caenorhabditis elegans model of tauopathy. METHODS To better understand how loss of D2-family dopamine receptors can ameliorate tau toxicity, we screened a collection of C. elegans mutations in dopamine-related genes (n = 45) for changes in tau transgene-induced behavioral defects. These included many genes responsible for dopamine synthesis, metabolism, and signaling downstream of the D2 receptors. RESULTS We identified one dopamine synthesis gene, DOPA decarboxylase (DDC), as a suppressor of tau toxicity in tau transgenic worms. Loss of the C. elegans DDC gene, bas-1, ameliorated the behavioral deficits of tau transgenic worms, reduced phosphorylated and detergent-insoluble tau accumulation, and reduced tau-mediated neuron loss. Loss of function in other genes in the dopamine and serotonin synthesis pathways did not alter tau-induced toxicity; however, their function is required for the suppression of tau toxicity by bas-1. Additional loss of D2-family dopamine receptors did not synergize with bas-1 suppression of tauopathy phenotypes. CONCLUSIONS Loss of the DDC bas-1 reduced tau-induced toxicity in a C. elegans model of tauopathy, while loss of no other dopamine or serotonin synthesis genes tested had this effect. Because loss of activity upstream of DDC could reduce suppression of tau by DDC, this suggests the possibility that loss of DDC suppresses tau via the combined accumulation of dopamine precursor levodopa and serotonin precursor 5-hydroxytryptophan.
Collapse
|
47
|
Fridolfsson HN, Herrera LA, Brandt JN, Cain NE, Hermann GJ, Starr DA. Genetic Analysis of Nuclear Migration and Anchorage to Study LINC Complexes During Development of Caenorhabditis elegans. Methods Mol Biol 2018; 1840:163-180. [PMID: 30141045 DOI: 10.1007/978-1-4939-8691-0_13] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Studying nuclear positioning in developing tissues of the model nematode Caenorhabditis elegans greatly contributed to the discovery of SUN and KASH proteins and the formation of the LINC model. Such studies continue to make important contributions into both how LINC complexes are regulated and how defects in LINC components disrupt normal development. The methods described explain how to observe and quantify the following: nuclear migration in embryonic dorsal hypodermal cells, nuclear migration through constricted spaces in larval P cells, nuclear positioning in the embryonic intestinal primordia, and nuclear anchorage in syncytial hypodermal cells. These methods will allow others to employ nuclear positioning in C. elegans as a model to further explore LINC complex regulation and function.
Collapse
Affiliation(s)
- Heidi N Fridolfsson
- Department of Molecular and Cellular Biology, University of California, Davis, CA, USA
| | - Leslie A Herrera
- Department of Molecular and Cellular Biology, University of California, Davis, CA, USA
| | - James N Brandt
- Department of Biology, Lewis and Clark College, Portland, OR, USA
| | - Natalie E Cain
- Department of Molecular and Cellular Biology, University of California, Davis, CA, USA
| | - Greg J Hermann
- Department of Biology, Lewis and Clark College, Portland, OR, USA
| | - Daniel A Starr
- Department of Molecular and Cellular Biology, University of California, Davis, CA, USA.
| |
Collapse
|
48
|
Sharma N, Khurana N, Muthuraman A. Lower vertebrate and invertebrate models of Alzheimer's disease - A review. Eur J Pharmacol 2017; 815:312-323. [PMID: 28943103 DOI: 10.1016/j.ejphar.2017.09.017] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 08/20/2017] [Accepted: 09/13/2017] [Indexed: 02/07/2023]
Abstract
Alzheimer's disease is a common neurodegenerative disorder which is characterized by the presence of beta- amyloid protein and neurofibrillary tangles (NFTs) in the brain. Till now, various higher vertebrate models have been in use to study the pathophysiology of this disease. But, these models possess some limitations like ethical restrictions, high cost, difficult maintenance of large quantity and lesser reproducibility. Besides, various lower chordate animals like Danio rerio, Drosophila melanogaster, Caenorhabditis elegans and Ciona intestinalis have been proved to be an important model for the in vivo determination of targets of drugs with least limitations. In this article, we reviewed different studies conducted on theses models for the better understanding of the pathophysiology of AD and their subsequent application as a potential tool in the preclinical evaluation of new drugs.
Collapse
Affiliation(s)
- Neha Sharma
- Department of Pharmaceutical Sciences, Lovely Professional University, Phagwara, Punjab, India
| | - Navneet Khurana
- Department of Pharmaceutical Sciences, Lovely Professional University, Phagwara, Punjab, India
| | - Arunachalam Muthuraman
- Department of Pharmacology, Akal College of Pharmacy and Technical Education, Mastuana Sahib, Sangrur, Punjab, India; Department of Pharmacology, JSS College of Pharmacy, Jagadguru Sri Shivarathreeshwara University, Mysuru 570015, Karnataka, India.
| |
Collapse
|
49
|
Kautu BB, Phillips J, Steele K, Mengarelli MS, Nord EA. A Behavioral Survey of the Effects of Kavalactones on Caenorhabditis elegans Neuromuscular Transmission. J Exp Neurosci 2017; 11:1179069517705384. [PMID: 28615969 PMCID: PMC5462554 DOI: 10.1177/1179069517705384] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Accepted: 03/23/2017] [Indexed: 12/16/2022] Open
Abstract
Kava is a plant root extract that is widely consumed by Pacific Islanders. Kava contains a class of lactone compounds called kavalactones. The sedative and anxiolytic effects of kava are likely attributed to the efficacies of kavalactones on the nervous system. Although some studies have implicated the potencies of certain kavalactone species on γ-aminobutyric acid transmission, evidence supporting the action of kavalactones on the eukaryotic neuromuscular junction (NMJ) and acetylcholine (ACh) transmission is scant. Here, we used behavioral assays to demonstrate the effects of kavalactones at the Caenorhabditis elegans NMJ. Our results suggest that kavalactones disrupt the inhibitory-excitatory balance at the NMJ. Such perturbation of NMJ activity is likely due to excess or prolonged ACh transmission. In addition, we found that kavain, a major constituent of kava, induced worm paralysis but not convulsions. Hence, the modulatory action of kavain could be distinct from the other kavalactone species.
Collapse
Affiliation(s)
| | | | - Kellie Steele
- Department of Biology, Greenville College, Greenville, IL, USA
| | | | - Eric A Nord
- Department of Biology, Greenville College, Greenville, IL, USA
| |
Collapse
|
50
|
Blazie SM, Geissel HC, Wilky H, Joshi R, Newbern J, Mangone M. Alternative Polyadenylation Directs Tissue-Specific miRNA Targeting in Caenorhabditis elegans Somatic Tissues. Genetics 2017; 206:757-774. [PMID: 28348061 PMCID: PMC5499184 DOI: 10.1534/genetics.116.196774] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 03/02/2017] [Indexed: 01/03/2023] Open
Abstract
mRNA expression dynamics promote and maintain the identity of somatic tissues in living organisms; however, their impact in post-transcriptional gene regulation in these processes is not fully understood. Here, we applied the PAT-Seq approach to systematically isolate, sequence, and map tissue-specific mRNA from five highly studied Caenorhabditis elegans somatic tissues: GABAergic and NMDA neurons, arcade and intestinal valve cells, seam cells, and hypodermal tissues, and studied their mRNA expression dynamics. The integration of these datasets with previously profiled transcriptomes of intestine, pharynx, and body muscle tissues, precisely assigns tissue-specific expression dynamics for 60% of all annotated C. elegans protein-coding genes, providing an important resource for the scientific community. The mapping of 15,956 unique high-quality tissue-specific polyA sites in all eight somatic tissues reveals extensive tissue-specific 3'untranslated region (3'UTR) isoform switching through alternative polyadenylation (APA) . Almost all ubiquitously transcribed genes use APA and harbor miRNA targets in their 3'UTRs, which are commonly lost in a tissue-specific manner, suggesting widespread usage of post-transcriptional gene regulation modulated through APA to fine tune tissue-specific protein expression. Within this pool, the human disease gene C. elegans orthologs rack-1 and tct-1 use APA to switch to shorter 3'UTR isoforms in order to evade miRNA regulation in the body muscle tissue, resulting in increased protein expression needed for proper body muscle function. Our results highlight a major positive regulatory role for APA, allowing genes to counteract miRNA regulation on a tissue-specific basis.
Collapse
Affiliation(s)
- Stephen M Blazie
- Molecular and Cellular Biology Graduate Program, Arizona State University, Tempe, Arizona 85281
- Virginia G. Piper Center for Personalized Diagnostics, The Biodesign Institute at Arizona State University, Tempe, Arizona 85281
| | - Heather C Geissel
- Molecular and Cellular Biology Graduate Program, Arizona State University, Tempe, Arizona 85281
- Virginia G. Piper Center for Personalized Diagnostics, The Biodesign Institute at Arizona State University, Tempe, Arizona 85281
| | - Henry Wilky
- Barrett Honors College, Arizona State University, Tempe, Arizona 85281
| | - Rajan Joshi
- College of Letters and Sciences, Interdisciplinary Studies, Biological Sciences and Informatics, Arizona State University, Tempe, Arizona 85281
| | - Jason Newbern
- Molecular and Cellular Biology Graduate Program, Arizona State University, Tempe, Arizona 85281
- Barrett Honors College, Arizona State University, Tempe, Arizona 85281
| | - Marco Mangone
- Molecular and Cellular Biology Graduate Program, Arizona State University, Tempe, Arizona 85281
- Virginia G. Piper Center for Personalized Diagnostics, The Biodesign Institute at Arizona State University, Tempe, Arizona 85281
- Barrett Honors College, Arizona State University, Tempe, Arizona 85281
| |
Collapse
|