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Liu H, Jang J, French AS, Torkkeli PH. Sequence analysis, homology modeling, tissue expression, and potential functions of seven putative acetylcholinesterases in the spider Cupiennius salei. Eur J Neurosci 2024. [PMID: 39230060 DOI: 10.1111/ejn.16524] [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: 06/06/2024] [Revised: 07/30/2024] [Accepted: 08/15/2024] [Indexed: 09/05/2024]
Abstract
Acetylcholine esterases (AChEs) are essential enzymes in cholinergic synapses, terminating neurotransmission by hydrolysing acetylcholine. While membrane bound AChEs at synaptic clefts efficiently perform this task, soluble AChEs are less stable and effective, but function over broader areas. In vertebrates, a single gene produces alternatively spliced forms of AChE, whereas invertebrates often have multiple genes, producing both enzyme types. Despite their significance as pesticide targets, the physiological roles of invertebrate AChEs remain unclear. Here, we characterized seven putative AChEs in the wandering spider, Cupiennius salei, a model species for neurophysiological studies. Sequence analyses and homology modeling predicted CsAChE7 as the sole stable, membrane-bound enzyme functioning at synaptic clefts, while the others are likely soluble enzymes. In situ hybridization of sections from the spider's nervous system revealed CsAChE7 transcripts co-localizing with choline acetyltransferase in cells that also exhibited AChE activity. CsAChE7 transcripts were also found in rapidly adapting mechanosensory neurons, suggesting a role in precise and transient activation of postsynaptic cells, contrasting with slowly adapting, also cholinergic, neurons expressing only soluble AChEs, which allow prolonged activation of postsynaptic cells. These findings suggest that cholinergic transmission is influenced not only by postsynaptic receptors but also by the enzymatic properties regulating acetylcholine clearance. We also show that acetylcholine is a crucial neurotransmitter in the spider's visual system and sensory and motor pathways, but absent in excitatory motor neurons at neuromuscular junctions, consistent with other arthropods. Our findings on sequence structures may have implications for the development of neurological drugs and pesticides.
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Affiliation(s)
- Hongxia Liu
- Department of Physiology and Biophysics, Dalhousie University, Halifax, NS, Canada
| | - Jinwon Jang
- Department of Physiology and Biophysics, Dalhousie University, Halifax, NS, Canada
| | - Andrew S French
- Department of Physiology and Biophysics, Dalhousie University, Halifax, NS, Canada
| | - Päivi H Torkkeli
- Department of Physiology and Biophysics, Dalhousie University, Halifax, NS, Canada
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2
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Pohl F, Lindsay-McGee V, Kong Thoo Lin P, Maciel P, Teixeira-Castro A. Pharmacological inhibition of acetylcholinesterase improves the locomotion defective phenotype of a SCA3 C. elegans model. MICROPUBLICATION BIOLOGY 2024; 2024:10.17912/micropub.biology.001086. [PMID: 38404918 PMCID: PMC10884831 DOI: 10.17912/micropub.biology.001086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Figures] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 12/22/2023] [Accepted: 02/02/2024] [Indexed: 02/27/2024]
Abstract
Inhibition of acetylcholinesterase (AChE) is a common used treatment option for Alzheimer's disease. However, there has been limited research on the potential use of AChE inhibitors for the treatment of Machado-Joseph disease (MJD)/Spinocerebellar Ataxia 3 (SCA3), in spite of the positive results using AChE inhibitors in patients with other inherited ataxias. MJD/SCA3, the most common form of dominant Spinocerebellar Ataxia worldwide, is caused by an expansion of the polyglutamine tract within the ataxin-3 protein, and is characterized by motor impairments. Our study shows that administration of the AChE inhibitor neostigmine is beneficial in treating the locomotion defective phenotype of a SCA3/MJD model of C. elegans and highlights the potential contribution of AChE enzymes to mutant ataxin-3-mediated toxicity.
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Affiliation(s)
- Franziska Pohl
- School of Pharmacy and Life Science, Robert Gordon University, Aberdeen, Scotland, United Kingdom
- Oncology/Dev. Biology, Washington University in St. Louis, St Louis, Missouri, United States
| | - Victoria Lindsay-McGee
- School of Pharmacy and Life Science, Robert Gordon University, Aberdeen, Scotland, United Kingdom
- The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, Scotland, United Kingdom
| | - Paul Kong Thoo Lin
- School of Pharmacy and Life Science, Robert Gordon University, Aberdeen, Scotland, United Kingdom
| | - Patricia Maciel
- Life and Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal
- Braga/Guimarães, Portugal, ICVS/3B’s-PT Government Associate Laboratory
| | - Andreia Teixeira-Castro
- Life and Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal
- Braga/Guimarães, Portugal, ICVS/3B’s-PT Government Associate Laboratory
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3
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Maleita C, Esteves I, Braga MEM, Figueiredo J, Gaspar MC, Abrantes I, de Sousa HC. Juglone and 1,4-Naphthoquinone-Promising Nematicides for Sustainable Control of the Root Knot Nematode Meloidogyne luci. FRONTIERS IN PLANT SCIENCE 2022; 13:867803. [PMID: 35656011 PMCID: PMC9152545 DOI: 10.3389/fpls.2022.867803] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Accepted: 04/19/2022] [Indexed: 05/16/2023]
Abstract
The scarce availability of efficient and eco-friendly nematicides to control root-knot nematodes (RKN), Meloidogyne spp., has encouraged research toward the development of bionematicides. Naphthoquinones, juglone (JUG) and 1,4-naphthoquinone (1,4-NTQ), are being explored as alternatives to synthetic nematicides to control RKN. This study expands the knowledge on the effects of these natural compounds toward M. luci life cycle (mortality, hatching, penetration, reproduction). M. luci second-stage juveniles (J2)/eggs were exposed to each compound (250, 150, 100, 50, and 20 ppm) to monitor nematode mortality and hatching during 72 h and 15 days, respectively. Tomato seedlings were then inoculated with 200 J2, which had been exposed to JUG/1,4-NTQ for 3 days. The number of nematodes inside the roots was determined at 3 days after inoculation, and the final population density was assessed at 45 days after inoculation. Moreover, the potential mode of action of JUG/1,4-NTQ was investigated for the first time on RKN, through the assessment of reactive oxygen species (ROS) generation, acetylcholinesterase (AChE) in vitro inhibitory activity and expression analysis of ache and glutathione-S-transferase (gst) genes. 1,4-NTQ was the most active compound, causing ≥50% J2 mortality at 250 ppm, within 24 h. At 20 and 50 ppm, hatching was reduced by ≈50% for both compounds. JUG showed a greater effect on M. luci penetration and reproduction, decreasing infection by ≈80% (50 ppm) on tomato plants. However, 1,4-NTQ-induced generation of ROS and nematode vacuolization was observed. Our study confirms that JUG/1,4-NTQ are promising nematicidal compounds, and new knowledge on their physiological impacts on Meloidogyne was provided to open new avenues for the development of innovative sustainable nematicides.
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Affiliation(s)
- Carla Maleita
- Department of Chemical Engineering, Chemical Process Engineering and Forest Products Research Centre, University of Coimbra, Coimbra, Portugal
- Department of Life Sciences, Centre for Functional Ecology – Science for People and the Planet, University of Coimbra, Coimbra, Portugal
| | - Ivânia Esteves
- Department of Life Sciences, Centre for Functional Ecology – Science for People and the Planet, University of Coimbra, Coimbra, Portugal
| | - Mara E. M. Braga
- Department of Chemical Engineering, Chemical Process Engineering and Forest Products Research Centre, University of Coimbra, Coimbra, Portugal
| | - Joana Figueiredo
- Department of Life Sciences, Centre for Functional Ecology – Science for People and the Planet, University of Coimbra, Coimbra, Portugal
| | - Marisa C. Gaspar
- Department of Chemical Engineering, Chemical Process Engineering and Forest Products Research Centre, University of Coimbra, Coimbra, Portugal
| | - Isabel Abrantes
- Department of Life Sciences, Centre for Functional Ecology – Science for People and the Planet, University of Coimbra, Coimbra, Portugal
| | - Hermínio C. de Sousa
- Department of Chemical Engineering, Chemical Process Engineering and Forest Products Research Centre, University of Coimbra, Coimbra, Portugal
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Navarro-Hortal MD, Romero-Márquez JM, Osta S, Jiménez-Trigo V, Muñoz-Ollero P, Varela-López A. Natural Bioactive Products and Alzheimer’s Disease Pathology: Lessons from Caenorhabditis elegans Transgenic Models. Diseases 2022; 10:diseases10020028. [PMID: 35645249 PMCID: PMC9149938 DOI: 10.3390/diseases10020028] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 04/28/2022] [Accepted: 05/04/2022] [Indexed: 02/04/2023] Open
Abstract
Alzheimer’s disease (AD) is an age-dependent, progressive disorder affecting millions of people. Currently, the therapeutics for AD only treat the symptoms. Although they have been used to discover new products of interest for this disease, mammalian models used to investigate the molecular determinants of this disease are often prohibitively expensive, time-consuming and very complex. On the other hand, cell cultures lack the organism complexity involved in AD. Given the highly conserved neurological pathways between mammals and invertebrates, Caenorhabditis elegans has emerged as a powerful tool for the investigation of the pathophysiology of human AD. Numerous models of both Tau- and Aβ-induced toxicity, the two prime components observed to correlate with AD pathology and the ease of performing RNA interference for any gene in the C. elegans genome, allow for the identification of multiple therapeutic targets. The effects of many natural products in main AD hallmarks using these models suggest promising health-promoting effects. However, the way in which they exert such effects is not entirely clear. One of the reasons is that various possible therapeutic targets have not been evaluated in many studies. The present review aims to explore shared therapeutical targets and the potential of each of them for AD treatment or prevention.
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Liu L, He S, Tang M, Zhang M, Wang C, Wang Z, Sun F, Yan Y, Li H, Lin K. Pseudo toxicity abatement effect of norfloxacin and copper combined exposure on Caenorhabditis elegans. CHEMOSPHERE 2022; 287:132019. [PMID: 34450372 DOI: 10.1016/j.chemosphere.2021.132019] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 08/21/2021] [Accepted: 08/23/2021] [Indexed: 06/13/2023]
Abstract
The coexistence of antibiotics and heavy metals may result in complex ecotoxicological effects on living organisms. In this work, the combined toxic effects of norfloxacin (NOR) and copper (Cu) on Caenorhabditis elegans (C. elegans) were investigated due to the highly possible co-pollution tendency. The results indicated that locomotion behaviors (frequency of head thrash and body bend) of C. elegans were more sensitive as the exposure time of NOR or Cu prolonged. Meanwhile, the physiological indexes (locomotion behaviors, body length) of C. elegans were more sensitive to the combined pollution that with lower Cu dosage (0.0125 μM), in prolonged exposure experiments. In addition, the toxic effects of NOR-Cu on physiological indexes of C. elegans seemed to be alleviated during prolonged exposure when Cu was 1.25 μM. Similarly, the ROS production and apoptosis level almost unchanged with the addition of NOR compared with Cu (1.25 μM) exposure groups, but both significantly higher than the control groups. Furthermore, compared with Cu (0.0125 μM and 1.25 μM) exposure experiments, the addition of NOR had resulted in the genetic expression decrease of hsp-16.1, hsp-16.2, hsp-16.48, and the oxidative stress in C. elegans seems to be alleviated. However, the significantly decreased of ape-1 and sod-3 expression indicated the disruption of ROS defense mechanism. The irregular change in ace-1 and ace-2 gene expressions in NOR-Cu (0.0125 μM) would result in the locomotion behaviors disorders of C. elegans, and this also explains why C. elegans are more sensitive to the combination of NOR and lower concentration of Cu.
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Affiliation(s)
- Lili Liu
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, School of Resources and Environmental Engineering, East China University of Science and Technology, Shanghai, 200237, China
| | - Siqi He
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, School of Resources and Environmental Engineering, East China University of Science and Technology, Shanghai, 200237, China
| | - Mingqi Tang
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, School of Resources and Environmental Engineering, East China University of Science and Technology, Shanghai, 200237, China
| | - Meng Zhang
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, School of Resources and Environmental Engineering, East China University of Science and Technology, Shanghai, 200237, China.
| | - Chen Wang
- Institute for Environmental Pollution and Health, School of Environmental and Chemical Engineering, Shanghai University, Shanghai, 200444, China
| | - Zhiping Wang
- School of Environment Science and Technology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Feifei Sun
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, School of Resources and Environmental Engineering, East China University of Science and Technology, Shanghai, 200237, China
| | - Ying Yan
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, School of Resources and Environmental Engineering, East China University of Science and Technology, Shanghai, 200237, China
| | - Hui Li
- Institute for Environmental Pollution and Health, School of Environmental and Chemical Engineering, Shanghai University, Shanghai, 200444, China
| | - Kuangfei Lin
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, School of Resources and Environmental Engineering, East China University of Science and Technology, Shanghai, 200237, China
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6
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Emerson S, Hay M, Smith M, Granger R, Blauch D, Snyder N, El Bejjani R. Acetylcholine signaling genes are required for cocaine-stimulated egg laying in Caenorhabditis elegans. G3 (BETHESDA, MD.) 2021; 11:jkab143. [PMID: 33914087 PMCID: PMC8763240 DOI: 10.1093/g3journal/jkab143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Accepted: 04/20/2021] [Indexed: 11/23/2022]
Abstract
The toxicity and addictive liability associated with cocaine abuse are well-known. However, its mode of action is not completely understood, and effective pharmacotherapeutic interventions remain elusive. The cholinergic effects of cocaine on acetylcholine receptors, synthetic enzymes, and degradative enzymes have been the focus of relatively little empirical investigation. Due to its genetic tractability and anatomical simplicity, the egg laying circuit of the hermaphroditic nematode, Caenorhabditis elegans, is a powerful model system to precisely examine the genetic and molecular targets of cocaine in vivo. Here, we report a novel cocaine-induced behavioral phenotype in C. elegans, cocaine-stimulated egg laying. In addition, we present the results of an in vivo candidate suppression screen of synthetic enzymes, receptors, degradative enzymes, and downstream components of the intracellular signaling cascades of the main neurotransmitter systems that control C. elegans egg laying. Our results show that cocaine-stimulated egg laying is dependent on acetylcholine synthesis and synaptic release, functional nicotinic acetylcholine receptors, and the C. elegans acetylcholinesterases.
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Affiliation(s)
- Soren Emerson
- Neuroscience Interdisciplinary Program, Davidson College, Davidson, NC 28035, USA
| | - Megan Hay
- Biology Department, Davidson College, Davidson, NC 28035, USA
| | - Mark Smith
- Neuroscience Interdisciplinary Program, Davidson College, Davidson, NC 28035, USA
- Psychology Department, Davidson College, Davidson, NC 28035, USA
| | - Ricky Granger
- Biology Department, Davidson College, Davidson, NC 28035, USA
| | - David Blauch
- Chemistry Department, Davidson College, Davidson, NC 28035 USA
| | - Nicole Snyder
- Chemistry Department, Davidson College, Davidson, NC 28035 USA
| | - Rachid El Bejjani
- Neuroscience Interdisciplinary Program, Davidson College, Davidson, NC 28035, USA
- Biology Department, Davidson College, Davidson, NC 28035, USA
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7
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Queirós L, Martins AC, Krum BN, Ke T, Aschner M, Pereira JL, Gonçalves FJM, Milne GL, Pereira P. Assessing the neurotoxicity of the carbamate methomyl in Caenorhabditis elegans with a multi-level approach. Toxicology 2021; 451:152684. [PMID: 33508380 DOI: 10.1016/j.tox.2021.152684] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 12/04/2020] [Accepted: 01/13/2021] [Indexed: 01/19/2023]
Abstract
The neurotoxicity and developmental effects of a widely applied insecticide (methomyl) was investigated by a multi-level approach (behavior and biometry, biochemical alterations and neurodegeneration) in Caenorhabditis elegans upon a short-term exposure (1 h) and a post-exposure period (48 h). The 1-h exposure to sub-lethal concentrations of methomyl (lower than 0.320 g L-1; i.e. below the estimated LC10) triggered significant changes on motor behavior and development impairment. The type of movement was significantly altered in methomyl-exposed worms, as well as biometric parameters (worms frequently idle and moving more backwards than controls; small body area, length and wavelength). These effects were followed by an increase of acetylcholine levels. Interestingly, after the 48-h recovery period, movement of previously exposed worms was similar to controls, and a concentration-dependent reversion of biometric endpoints was recorded, pointing out the transient action of the carbamate in line with an apparent absence of cholinergic neurons damage. This study provided new insight on the neurotoxicity of methomyl by showing that effects on movement and development were transient, and apparently did not result in neurodegeneration in cholinergic neurons. Moreover, these findings reinforced the advantages of using C. elegans in a multi-level approach for pesticide effects assessment.
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Affiliation(s)
- L Queirós
- Department of Biology & CESAM (Centre for Environmental and Marine Studies), University of Aveiro, 3810-193, Aveiro, Portugal; Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA.
| | - A C Martins
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - B N Krum
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Physiology and Pharmacology, Federal University of Santa Maria, 97105-900, Santa Maria, RS, Brazil
| | - T Ke
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - M Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; IM Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia
| | - J L Pereira
- Department of Biology & CESAM (Centre for Environmental and Marine Studies), University of Aveiro, 3810-193, Aveiro, Portugal
| | - F J M Gonçalves
- Department of Biology & CESAM (Centre for Environmental and Marine Studies), University of Aveiro, 3810-193, Aveiro, Portugal
| | - G L Milne
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN, 37240, USA
| | - P Pereira
- Department of Biology & CESAM (Centre for Environmental and Marine Studies), University of Aveiro, 3810-193, Aveiro, Portugal
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8
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Paul D, Chipurupalli S, Justin A, Raja K, Mohankumar SK. Caenorhabditis elegans as a possible model to screen anti-Alzheimer's therapeutics. J Pharmacol Toxicol Methods 2020; 106:106932. [PMID: 33091537 DOI: 10.1016/j.vascn.2020.106932] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 09/28/2020] [Accepted: 09/29/2020] [Indexed: 01/06/2023]
Abstract
Alzheimer's disease (AD) is regarded as one of the significant health burdens, as the prevalence is raising worldwide and gradually reaching to epidemic proportions. Consequently, a number of scientific investigations have been initiated to derive therapeutics to combat AD with a concurrent advancement in pharmacological methods and experimental models. Whilst, the available experimental pharmacological approaches both in vivo and in vitro led to the development of AD therapeutics, the precise manner by which experimental models mimic either one or more biomarkers of human pathology of AD is gaining scientific attentions. Caenorhabditis elegans (C. elegans) has been regarded as an emerging model for various reasons, including its high similarities with the biomarkers of human AD. Our review supports the versatile nature of C. elegans and collates that it is a well-suited model to elucidate various molecular mechanisms by which AD therapeutics elicit their pharmacological effects. It is apparent that C. elegans is capable of establishing the pathological processes that links the endoplasmic reticulum and mitochondria dysfunctions in AD, exploring novel molecular cascades of AD pathogenesis and underpinning causal and consequential changes in the associated proteins and genes. In summary, C. elegans is a unique and feasible model for the screening of anti-Alzheimer's therapeutics and has the potential for further scientific exploration.
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Affiliation(s)
- Deepraj Paul
- TIFAC CORE in Herbal Drugs, Department of Pharmacognosy, JSS College of Pharmacy, JSS Academy of Higher Education & Research, Rockland's, Ooty 643001, Tamil Nadu, India
| | - Sandhya Chipurupalli
- Department of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research, Rockland's, Ooty 643001, Tamil Nadu, India
| | - Antony Justin
- Department of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research, Rockland's, Ooty 643001, Tamil Nadu, India
| | - Kalpana Raja
- Regenerative Biology, Morgridge Institute of Research, Madison, WI, USA
| | - Suresh K Mohankumar
- TIFAC CORE in Herbal Drugs, Department of Pharmacognosy, JSS College of Pharmacy, JSS Academy of Higher Education & Research, Rockland's, Ooty 643001, Tamil Nadu, India.
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9
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Sammi SR, Rawat JK, Raghav N, Kumar A, Roy S, Singh M, Gautam S, Yadav RK, Devi U, Pandey R, Kaithwas G. Galantamine attenuates N,N-dimethyl hydrazine induced neoplastic colon damage by inhibiting acetylcholinesterase and bimodal regulation of nicotinic cholinergic neurotransmission. Eur J Pharmacol 2017; 818:174-183. [PMID: 29074413 DOI: 10.1016/j.ejphar.2017.10.036] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Revised: 10/18/2017] [Accepted: 10/19/2017] [Indexed: 02/08/2023]
Abstract
The present study reveals the effect of galantamine (GAL) against 1, 2-dimethylhydrazine (DMH) induced colon cancer. Wistar albino rats were arbitrarily divided into four groups (n = 8). Group 1 served as normal control (normal saline, 3ml/kg/day, p.o.); group 2, 3 and 4 received DMH (20mg/kg/week, s.c.), for 6 weeks; groups 3 and 4 also received GAL (2 and 4mg/kg/day, p.o) for 6 weeks. DMH treated rats showed decreased heart rate variability (HRV) factors, increased incidence of aberrant crypt foci (ACF), increased thiobarbituric acid reactive substances (TBARs) along with the decrease in the enzymatic activity of superoxide dismutase (SOD) and catalase. Increased levels of inflammatory marker cyclooxygenase (COX) and lipoxygenase (LOX) was also evident in DMH treated animals. The colonic surface architecture was studied using scanning electron microscopy revealed aberrant crypts(X500) and neoplastic nodules (X2000). GAL treatment helped to minimize the ACF count, restored oxidative stress and inflammatory markers favorably. To further validate our results, our study was directed to define the effect of GAL on acetylcholine neurotransmission using a simple model organism, Caenorhabditis elegans (C. elegans). Increased synaptic cholinergic transmission by GAL (32µM) was evident in the worms when studied through aldicarb assay. However, GAL (32µM) treatment negatively modulated α7 nicotinic acetylcholine receptor (α7nAch receptor), when evaluated using the levamisole assay. GAL (32µM) treatment down regulated the genomic expression of ace-1, ace-2 along with unc-29, unc-38, and unc-50 (essential components of α7 nAch receptor). GAL by inhibiting AchE and regulating Alpha7nACh activity can improve cholinergic neurotransmission.
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Affiliation(s)
- Shreesh Raj Sammi
- Department of Microbial Technology and Nematology, CSIR-Central Institute of Medicinal and Aromatic Plants, Near Kukrail Picnic Spot, Lucknow, India
| | - Jitendra K Rawat
- Department of Pharmaceutical Sciences, School of Biosciences and Biotechnology, Babasaheb Bhimrao Ambedkar University (A Central University), Lucknow, Uttar Pradesh, India
| | - Neetu Raghav
- Department of Pharmaceutical Sciences, School of Biosciences and Biotechnology, Babasaheb Bhimrao Ambedkar University (A Central University), Lucknow, Uttar Pradesh, India
| | - Ajay Kumar
- Department of Pharmaceutical Sciences, School of Biosciences and Biotechnology, Babasaheb Bhimrao Ambedkar University (A Central University), Lucknow, Uttar Pradesh, India
| | - Subhadeep Roy
- Department of Pharmaceutical Sciences, School of Biosciences and Biotechnology, Babasaheb Bhimrao Ambedkar University (A Central University), Lucknow, Uttar Pradesh, India
| | - Manjari Singh
- Department of Pharmaceutical Sciences, School of Biosciences and Biotechnology, Babasaheb Bhimrao Ambedkar University (A Central University), Lucknow, Uttar Pradesh, India
| | - Swetlana Gautam
- Department of Pharmaceutical Sciences, School of Biosciences and Biotechnology, Babasaheb Bhimrao Ambedkar University (A Central University), Lucknow, Uttar Pradesh, India
| | - Rajnish K Yadav
- Department of Pharmaceutical Sciences, School of Biosciences and Biotechnology, Babasaheb Bhimrao Ambedkar University (A Central University), Lucknow, Uttar Pradesh, India
| | - Uma Devi
- Department of Pharmaceutical Sciences, Faculty of Health Medical Sciences Indigenous and Alternative Medicine, SHIATS- Deemed to be University, Formerly Allahabad Agricultural Institute Naini, Allahabad, U.P., India
| | - Rakesh Pandey
- Department of Microbial Technology and Nematology, CSIR-Central Institute of Medicinal and Aromatic Plants, Near Kukrail Picnic Spot, Lucknow, India
| | - Gaurav Kaithwas
- Department of Pharmaceutical Sciences, School of Biosciences and Biotechnology, Babasaheb Bhimrao Ambedkar University (A Central University), Lucknow, Uttar Pradesh, India.
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10
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Mou X, Yuan GR, Jiang HB, Liu Z, Wang JJ. Functional characterization of two acetylcholinesterase genes in the brown citrus aphid, Aphis (Toxoptera) citricidus (Kirkaldy), using heterologous expression and RNA interference. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2017; 138:76-83. [PMID: 28456308 DOI: 10.1016/j.pestbp.2017.03.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Revised: 02/08/2017] [Accepted: 03/01/2017] [Indexed: 06/07/2023]
Abstract
Acetylcholinesterase (AChE) is the primary target of organophosphate- and carbamate-based insecticides. We sequenced the full-length cDNAs of two AChE genes from the brown citrus aphid Aphis (Toxoptera) citricidus (Kirkaldy). These two genes, Tcace1 and Tcace2, which encode TcAChE1 and TcAChE2, respectively, had a shared amino acid identity of 29% and were highly similar to other insect ace1 and ace2 genes, respectively, having specific functional motifs. Potential differences in enzymatic function were characterized by the heterologous expression of the two genes using a baculovirus system in Sf9 insect cells. Both of the recombinant AChEs had high specific activities for three typical substrates, acetylthiocholine iodide, butyrylthiocholine iodide, and propinylthiocholine iodide. TcAChE1 had a lower Michaelis-Menten constant value and a higher maximal reaction velocity than recombinant TcAChE2, indicating a higher affinity for substrates and greater catalytic efficiency, respectively. Bioassays showed a greater sensitivity of recombinant TcAChE1 to the 10 tested insecticides. Silencing of Tcace1 and Tcace2 by RNA interference significantly increased the susceptibility of A. citricidus to malathion and carbaryl; however, silencing Tcace1 resulted in a higher mortality rate than silencing Tcace2. Additionally, the specific enzyme activity decreased more after silencing Tcace1 than after silencing Tcace2. Thus, TcAChE1 plays a major role in postsynaptic neurotransmission in A. citricidus.
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Affiliation(s)
- Xing Mou
- Key Laboratory of Entomology and Pest Control Engineering, College of Plant Protection, Southwest University, Chongqing 400716, People's Republic of China
| | - Guo-Rui Yuan
- Key Laboratory of Entomology and Pest Control Engineering, College of Plant Protection, Southwest University, Chongqing 400716, People's Republic of China
| | - Hong-Bo Jiang
- Key Laboratory of Entomology and Pest Control Engineering, College of Plant Protection, Southwest University, Chongqing 400716, People's Republic of China
| | - Zhao Liu
- Key Laboratory of Entomology and Pest Control Engineering, College of Plant Protection, Southwest University, Chongqing 400716, People's Republic of China
| | - Jin-Jun Wang
- Key Laboratory of Entomology and Pest Control Engineering, College of Plant Protection, Southwest University, Chongqing 400716, People's Republic of China.
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11
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Cui R, Zhang L, Chen Y, Huang W, Fan C, Wu Q, Peng D, da Silva W, Sun X. Expression and evolutionary analyses of three acetylcholinesterase genes (Mi-ace-1, Mi-ace-2, Mi-ace-3) in the root-knot nematode Meloidogyne incognita. Exp Parasitol 2017; 176:75-81. [PMID: 28238686 DOI: 10.1016/j.exppara.2017.01.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2016] [Revised: 01/14/2017] [Accepted: 01/27/2017] [Indexed: 01/30/2023]
Abstract
The full cDNA of Mi-ace-3 encoding an acetylcholinesterase (AChE) in Meloidogyne incognita was cloned and characterized. Mi-ace-3 had an open reading frame of 1875 bp encoding 624 amino acid residues. Key residues essential to AChE structure and function were conserved. The deduced Mi-ACE-3 protein sequence had 72% amino acid similarity with that of Ditylenchus destructor Dd-AChE-3. Phylogenetic analyses using 41 AChEs from 24 species showed that Mi-ACE-3 formed a cluster with 4 other nematode AChEs. Our results revealed that the Mi-ace-3 cloned in this study, which is orthologous to Caenorhabditis elegans AChE, belongs to the nematode ACE-3/4 subgroup. There was a significant reduction in the number of galls in transgenic tobacco roots when Mi-ace-1, Mi-ace-2, and Mi-ace-3 were knocked down simultaneously, whereas little or no effect were observed when only one or two of these genes were knocked down. This is an indication that the functions of these three genes are redundant.
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Affiliation(s)
- Ruqiang Cui
- College of Agronomy/ Key Laboratory of Crop Physiology, Ecology and Genetic Breeding, Ministry of Education, Jiangxi Agricultural University, Nanchang, Jiangxi, China.
| | - Lei Zhang
- College of Agronomy/ Key Laboratory of Crop Physiology, Ecology and Genetic Breeding, Ministry of Education, Jiangxi Agricultural University, Nanchang, Jiangxi, China
| | - Yuyan Chen
- College of Agronomy/ Key Laboratory of Crop Physiology, Ecology and Genetic Breeding, Ministry of Education, Jiangxi Agricultural University, Nanchang, Jiangxi, China
| | - Wenkun Huang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Chengming Fan
- Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
| | - Qingsong Wu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Deliang Peng
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Washington da Silva
- School of Integrative Plant Science, Plant Pathology and Plant-Microbe Biology Section, Cornell University, Ithaca, NY 14853, USA
| | - Xiaotang Sun
- College of Agronomy/ Key Laboratory of Crop Physiology, Ecology and Genetic Breeding, Ministry of Education, Jiangxi Agricultural University, Nanchang, Jiangxi, China.
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12
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Hagstrom D, Hirokawa H, Zhang L, Radic Z, Taylor P, Collins EMS. Planarian cholinesterase: in vitro characterization of an evolutionarily ancient enzyme to study organophosphorus pesticide toxicity and reactivation. Arch Toxicol 2016; 91:2837-2847. [PMID: 27990564 DOI: 10.1007/s00204-016-1908-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Accepted: 12/06/2016] [Indexed: 12/17/2022]
Abstract
The freshwater planarian Dugesia japonica has recently emerged as an animal model for developmental neurotoxicology and found to be sensitive to organophosphorus (OP) pesticides. While previous activity staining of D. japonica, which possess a discrete cholinergic nervous system, has shown acylthiocholine catalysis, it is unknown whether this is accomplished through an acetylcholinesterase (AChE), butyrylcholinesterase (BChE), or a hybrid esterase and how OP exposure affects esterase activity. Here, we show that the majority of D. japonica cholinesterase (DjChE) activity departs from conventional AChE and BChE classifications. Inhibition by classic protonable amine and quaternary reversible inhibitors (ethopropazine, donepezil, tacrine, edrophonium, BW284c51, propidium) shows that DjChE is far less sensitive to these inhibitors than human AChE, suggesting discrete differences in active center and peripheral site recognition and structures. Additionally, we find that different OPs (chlorpyrifos oxon, paraoxon, dichlorvos, diazinon oxon, malaoxon) and carbamylating agents (carbaryl, neostigmine, physostigmine, pyridostigmine) differentially inhibit DjChE activity in vitro. DjChE was most sensitive to diazinon oxon and neostigmine and least sensitive to malaoxon and carbaryl. Diazinon oxon-inhibited DjChE could be reactivated by the quaternary oxime, pralidoxime (2-PAM), and the zwitterionic oxime, RS194B, with RS194B being significantly more potent. Sodium fluoride (NaF) reactivates OP-DjChE faster than 2-PAM. As one of the most ancient true cholinesterases, DjChE provides insight into the evolution of a hybrid enzyme before the separation into distinct AChE and BChE enzymes found in higher vertebrates. The sensitivity of DjChE to OPs and capacity for reactivation validate the use of planarians for OP toxicology studies.
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Affiliation(s)
- Danielle Hagstrom
- Division of Biological Sciences, University of California, San Diego, La Jolla, CA, 92093, USA
| | - Hideto Hirokawa
- Department of Pharmacology, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, 92093, USA
| | - Limin Zhang
- Department of Pharmacology, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, 92093, USA
| | - Zoran Radic
- Department of Pharmacology, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, 92093, USA
| | - Palmer Taylor
- Department of Pharmacology, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, 92093, USA.
| | - Eva-Maria S Collins
- Division of Biological Sciences, University of California, San Diego, La Jolla, CA, 92093, USA. .,Department of Physics, University of California, San Diego, La Jolla, CA, 92093, USA.
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13
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Huang WK, Wu QS, Peng H, Kong LA, Liu SM, Yin HQ, Cui RQ, Zhan LP, Cui JK, Peng DL. Mutations in Acetylcholinesterase2 (ace2) increase the insensitivity of acetylcholinesterase to fosthiazate in the root-knot nematode Meloidogyne incognita. Sci Rep 2016; 6:38102. [PMID: 27897265 PMCID: PMC5126670 DOI: 10.1038/srep38102] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Accepted: 11/04/2016] [Indexed: 12/05/2022] Open
Abstract
The root-knot nematode Meloidogyne incognita causes severe damage to continuously cropping vegetables. The control of this nematode relies heavily on organophosphate nematicides in China. Here, we described resistance to the organophosphate nematicide fosthiazate in a greenhouse-collected resistant population (RP) and a laboratory susceptible population (SP) of M. incognita. Fosthiazate was 2.74-fold less toxic to nematodes from RP than that from SP. Quantitative real-time PCR revealed that the acetylcholinesterase2 (ace2) transcription level in the RP was significantly higher than that in the SP. Eighteen nonsynonymous amino acid differences in ace2 were observed between the cDNA fragments of the RP and SP. The acetylcholinesterase (AChE) protein activity in the RP was significantly reduced compared with that in the SP. After knocking down the ace2 gene, the ace2 transcription level was significantly decreased, but no negative impact on the infection of juveniles was observed. The 50% lethal concentration of the RNAi RP population decreased 40%, but the inhibition rate of fosthiazate against AChE activity was significantly increased in RP population. Thus, the increased fosthiazate insensitivity in the M. incognita resistant population was strongly associated with mutations in ace2. These results provide valuable insights into the resistance mechanism of root-knot nematode to organophosphate nematicides.
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Affiliation(s)
- Wen-Kun Huang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Qin-Song Wu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Huan Peng
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Ling-An Kong
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Shi-Ming Liu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Hua-Qun Yin
- School of Minerals Processing and Bioengineering, Central South University, Changsha, 410083, China.,Key Laboratory of Biometallurgy of Ministry of Education, Central South University, Changsha, 410083, China
| | - Ru-Qiang Cui
- School of Agricultural Sciences, Jiangxi Agricultural University, Nanchang, 330045, China
| | - Li-Ping Zhan
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Jiang-Kuan Cui
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - De-Liang Peng
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
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Sammi SR, Trivedi S, Rath SK, Nagar A, Tandon S, Kalra A, Pandey R. 1-Methyl-4-propan-2-ylbenzene from Thymus vulgaris Attenuates Cholinergic Dysfunction. Mol Neurobiol 2016; 54:5468-5481. [PMID: 27599497 DOI: 10.1007/s12035-016-0083-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2016] [Accepted: 08/23/2016] [Indexed: 01/16/2023]
Abstract
Cholinergic dysfunction is manifested in a plethora of neurodegenerative and psychiatric disorders such as Alzheimer's, Parkinson's, and Huntington's diseases. The extent of cholinergic affliction is maximum in Alzheimer's disease which is a progressive neurodegenerative disorder involving death of cholinergic neurons. To this date, the therapeutic management of cholinergic dysfunction is limited to provide symptomatic relief through the use of acetylcholinesterase (Ache) inhibitors only. The present study elaborates the potential of thyme oil and its individual components in curtailing cholinergic deficits. We found that thyme oil augments neurotransmission by modulating synaptic acetylcholine (Ach) levels and nicotinic acetylcholine receptor activity, being orchestrated through upregulation of genes cho-1, unc-17 and unc-50. Studies on individual components revealed para-cymene (1-methyl-4-propan-2-ylbenzene) as the active component of thyme oil, contributing its effects through upregulation of cho-1, cha-1, unc-17 and unc-50, while downregulating ace-1 and ace-2. Interestingly, thymol and gamma-terpinene which although were devoid of any activity individually, exhibited significantly enhanced synaptic Ach levels and nicotinic acetylcholine receptor (nAchR) responsiveness, when administered in combination. Our findings advocate thyme oil and its constituents as potential candidates for amelioration of cholinergic dysfunction. The study is speculated to make a way for a new line of "phytomolecules-based drugs" from the diverse pool of natural compounds.
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Affiliation(s)
- Shreesh Raj Sammi
- Department of Microbial Technology and Nematology, CSIR-Central Institute of Medicinal and Aromatic Plants, Near Kukrail Picnic Spot, Lucknow, 226015, India
| | - Shalini Trivedi
- Department of Microbial Technology and Nematology, CSIR-Central Institute of Medicinal and Aromatic Plants, Near Kukrail Picnic Spot, Lucknow, 226015, India
| | - Srikanta Kumar Rath
- Division of Toxicology, CSIR-Central Drug Research Institute, Lucknow, 226031, India
| | - Abhishek Nagar
- Department of Process Chemistry, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, 226015, India
| | - Sudeep Tandon
- Department of Process Chemistry, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, 226015, India
| | - Alok Kalra
- Microbiology and Entomology, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, 226015, India
| | - Rakesh Pandey
- Department of Microbial Technology and Nematology, CSIR-Central Institute of Medicinal and Aromatic Plants, Near Kukrail Picnic Spot, Lucknow, 226015, India.
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15
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Mishra RK, Sammi SR, Rawat JK, Roy S, Singh M, Gautam S, Yadav RK, Devi U, Ansari MN, Saeedan AS, Saraf SA, Pandey R, Kaithwas G. Palonosetron attenuates 1,2-dimethyl hydrazine induced preneoplastic colon damage through downregulating acetylcholinesterase expression and up-regulating synaptic acetylcholine concentration. RSC Adv 2016. [DOI: 10.1039/c6ra04614b] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The present study was undertaken to evaluate the effect of palonosetron (PAL) against 1,2-dimethylhydrazine (DMH)-induced colon cancer.
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16
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Sammi SR, Mishra DP, Trivedi S, Smita SS, Nagar A, Tandon S, Pandey R. Citrus hystrix-derived 3,7-dimethyloct-6-enal and 3,7-dimethyloct-6-enyl acetate ameliorate acetylcholine deficits. RSC Adv 2016. [DOI: 10.1039/c6ra12522k] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Cholinergic neurotransmission is an affliction in a plethora of neurodegenerative disorders such as Alzheimer’s, Huntington’s and Parkinson’s diseases and some psychiatric disorders like schizophrenia.
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Affiliation(s)
- Shreesh Raj Sammi
- Department of Microbial Technology and Nematology
- CSIR-Central Institute of Medicinal and Aromatic Plants
- Lucknow
- India
| | | | - Shalini Trivedi
- Department of Microbial Technology and Nematology
- CSIR-Central Institute of Medicinal and Aromatic Plants
- Lucknow
- India
| | - Shachi S. Smita
- Department of Microbial Technology and Nematology
- CSIR-Central Institute of Medicinal and Aromatic Plants
- Lucknow
- India
| | - Abhishek Nagar
- Department of Process Chemistry
- CSIR-Central Institute of Medicinal and Aromatic Plants
- Lucknow
- India
| | - Sudeep Tandon
- Department of Process Chemistry
- CSIR-Central Institute of Medicinal and Aromatic Plants
- Lucknow
- India
| | - Rakesh Pandey
- Department of Microbial Technology and Nematology
- CSIR-Central Institute of Medicinal and Aromatic Plants
- Lucknow
- India
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17
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Identification and Molecular Characterization of Two Acetylcholinesterases from the Salmon Louse, Lepeophtheirus salmonis. PLoS One 2015; 10:e0125362. [PMID: 25938836 PMCID: PMC4418574 DOI: 10.1371/journal.pone.0125362] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Accepted: 03/10/2015] [Indexed: 11/21/2022] Open
Abstract
Acetylcholinesterase (AChE) is an important enzyme in cholinergic synapses. Most arthropods have two genes (ace1 and ace2), but only one encodes the predominant synaptic AChE, the main target for organophosphates. Resistance towards organophosphates is widespread in the marine arthropod Lepeophtheirus salmonis. To understand this trait, it is essential to characterize the gene(s) coding for AChE(s). The full length cDNA sequences encoding two AChEs in L. salmonis were molecularly characterized in this study. The two ace genes were highly similar (83.5% similarity at protein level). Alignment to the L. salmonis genome revealed that both genes were located close to each other (separated by just 26.4 kbp on the L. salmonis genome), resulting from a recent gene duplication. Both proteins had all the typical features of functional AChE and clustered together with AChE-type 1 proteins in other species, an observation that has not been described in other arthropods. We therefore concluded the presence of two versions of ace1 gene in L. salmonis, named ace1a and ace1b. Ace1a was predominantly expressed in different developmental stages compared to ace1b and was possibly active in the cephalothorax, indicating that ace1a is more likely to play the major role in cholinergic synaptic transmission. The study is essential to understand the role of AChEs in resistance against organophosphates in L. salmonis.
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18
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Koren Y, Sznitman R, Arratia PE, Carls C, Krajacic P, Brown AEX, Sznitman J. Model-independent phenotyping of C. elegans locomotion using scale-invariant feature transform. PLoS One 2015; 10:e0122326. [PMID: 25816290 PMCID: PMC4376858 DOI: 10.1371/journal.pone.0122326] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Accepted: 02/11/2015] [Indexed: 11/29/2022] Open
Abstract
To uncover the genetic basis of behavioral traits in the model organism C. elegans, a common strategy is to study locomotion defects in mutants. Despite efforts to introduce (semi-)automated phenotyping strategies, current methods overwhelmingly depend on worm-specific features that must be hand-crafted and as such are not generalizable for phenotyping motility in other animal models. Hence, there is an ongoing need for robust algorithms that can automatically analyze and classify motility phenotypes quantitatively. To this end, we have developed a fully-automated approach to characterize C. elegans’ phenotypes that does not require the definition of nematode-specific features. Rather, we make use of the popular computer vision Scale-Invariant Feature Transform (SIFT) from which we construct histograms of commonly-observed SIFT features to represent nematode motility. We first evaluated our method on a synthetic dataset simulating a range of nematode crawling gaits. Next, we evaluated our algorithm on two distinct datasets of crawling C. elegans with mutants affecting neuromuscular structure and function. Not only is our algorithm able to detect differences between strains, results capture similarities in locomotory phenotypes that lead to clustering that is consistent with expectations based on genetic relationships. Our proposed approach generalizes directly and should be applicable to other animal models. Such applicability holds promise for computational ethology as more groups collect high-resolution image data of animal behavior.
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Affiliation(s)
- Yelena Koren
- Department of Biomedical Engineering, Technion—Israel Institute of Technology, Israel
| | - Raphael Sznitman
- Ophthalmic Technology Group, ARTORG Center, University of Bern, Switzerland
| | - Paulo E. Arratia
- Department of Mechanical Engineering and Applied Mechanics, University of Pennsylvania, Philadelphia PA, USA
| | - Christopher Carls
- Department of Biomedical Sciences, West Virginia School of Osteopathic Medicine, Lewisburg WV, USA
| | - Predrag Krajacic
- Department of Biomedical Sciences, West Virginia School of Osteopathic Medicine, Lewisburg WV, USA
| | - André E. X. Brown
- MRC Clinical Sciences Centre, Faculty of Medicine, Imperial College London, UK
| | - Josué Sznitman
- Department of Biomedical Engineering, Technion—Israel Institute of Technology, Israel
- * E-mail:
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19
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Zhang Y, Shao Y, Jiang F, Li J, Liu Z. Identification of two acetylcholinesterases in Pardosa pseudoannulata and the sensitivity to insecticides. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2014; 46:25-30. [PMID: 24463359 DOI: 10.1016/j.ibmb.2014.01.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2013] [Revised: 01/09/2014] [Accepted: 01/13/2014] [Indexed: 06/03/2023]
Abstract
Pardosa pseudoannulata is an important predatory enemy against insect pests, such as rice planthoppers and leafhoppers. In order to understand the insecticide selectivity between P. pseudoannulata and insect pests, two acetylcholinesterase genes, Pp-ace1 and Pp-ace2, were cloned from this natural enemy. The putative proteins encoded by Pp-ace1 and Pp-ace2 showed high similarities to insect AChE1 (63% to Liposcelis entomophila AChE1) and AChE2 (36% to Culex quinquefasciatus AChE2) with specific functional motifs, which indicated that two genes might encode AChE1 and AChE2 proteins respectively. The recombinant proteins by expressing Pp-ace1 and Pp-ace2 genes in insect sf9 cells showed high AChE activities. The kinetic parameters, Vmax and Km, of two recombinant AChE proteins were significantly different. The sensitivities to six insecticides were determined in two recombinant AChEs. Pp-AChE1 was more sensitive to all tested insecticides than Pp-AChE2, such as fenobucarb (54 times in Ki ratios), isoprocarb (31 times), carbaryl (13 times) and omethoate (6 times). These results indicated that Pp-AChE1 might be the major synaptic enzyme in the spider. By sequence comparison of P. pseudoannulata and insect AChEs, the key amino acid differences at or close to the functional sites were found. The locations of some key amino acid differences were consistent with the point mutation sites in insect AChEs that were associated with insecticide resistance, such as Phe331 in Pp-AChE2 corresponding to Ser331Phe mutation in Myzus persicae and Aphis gossypii AChE2, which might play important roles in insecticide selectivity between P. pseudoannulata and insect pests. Of course, the direct evidences are needed through further studies.
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Affiliation(s)
- Yixi Zhang
- Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China; Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China
| | - Ying Shao
- Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China; Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China
| | - Feng Jiang
- Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China
| | - Jian Li
- Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China
| | - Zewen Liu
- Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China.
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Meyer D, Williams PL. Toxicity testing of neurotoxic pesticides in Caenorhabditis elegans. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART B, CRITICAL REVIEWS 2014; 17:284-306. [PMID: 25205216 DOI: 10.1080/10937404.2014.933722] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
The use of pesticides is ubiquitous worldwide, and these chemicals exert adverse effects on both target and nontarget species. Understanding the modes of action of pesticides, as well as quantifying exposure concentration and duration, is an important goal of clinicians and environmental health scientists. Some chemical exposures result in adverse effects on the nervous system. The nematode Caenorhabditis elegans (C. elegans) is a model lab organism well established for studying neurotoxicity, since the components of its nervous system are mapped and known, and most of its neurotransmitters correspond to human homologs. This review encompasses published studies in which C. elegans nematodes were exposed to pesticides with known neurotoxic actions. Endpoints measured include changes in locomotion, feeding behavior, brood size, growth, life span, and cell death. From data presented, evidence indicates that C. elegans can serve a role in assessing the effects of neurotoxic pesticides at the sublethal cellular level, thereby advancing our understanding of the mechanisms underlying toxicity induced by these chemicals. A proposed toxicity testing scheme for water-soluble chemicals is also included.
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Affiliation(s)
- Dean Meyer
- a Department of Environmental Health Science , College of Public Health, The University of Georgia , Athens , Georgia , USA
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21
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Xin L, Yamujala R, Wang Y, Wang H, Wu WH, Lawton MA, Long C, Di R. Acetylcholineestarase-inhibiting alkaloids from Lycoris radiata delay paralysis of amyloid beta-expressing transgenic C. elegans CL4176. PLoS One 2013; 8:e63874. [PMID: 23675513 PMCID: PMC3652842 DOI: 10.1371/journal.pone.0063874] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2013] [Accepted: 04/10/2013] [Indexed: 11/18/2022] Open
Abstract
The limited symptom relief and side effects of current Alzheimer’s disease (AD) medications warrant urgent discovery and study of new anti-AD agents. The “cholinergic hypothesis” of AD prompts us to search for plant-derived acetylcholineesterase (AChE) inhibitors such as galanthamine that has been licensed in Europe for AD treatment. We used the unique amyloid β-expressing transgenic C. elegans CL4176, which exhibits paralysis when human Aβ1–42 is induced, to study two natural benzylphenethylamine alkaloids isolated from Lycoris radiata (L’ Her.) Herb, galanthamine and haemanthidine, and their synthetic derivatives 1,2-Di-O-acetyllycorine and 1-O-acetyllycorine for their anti-paralysis effects. Our data indicate that these Lycoris compounds effectively delay the paralysis of CL4176 worms upon temperature up-shift, and prolong the lives of these transgenic worms. Lycoris compounds were shown to significantly inhibit the gene expression of ace-1 and ace-2. Additionally, the Lycoris compounds may modulate inflammatory and stress-related gene expressions to combat the Aβ-toxicity in C. elegans.
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Affiliation(s)
- Lijuan Xin
- College of Life and Environmental Sciences, Minzu University of China, Beijing, China
- Department of Plant Biology and Pathology, School of Environmental and Biological Sciences, Rutgers University, New Brunswick, New Jersey, United States of America
| | - Ritupriya Yamujala
- New Brunswick Graduate School, Rutgers University, New Brunswick, New Jersey, United States of America
| | - Yuehu Wang
- Key Laboratory of Economic Plants and Biotechnology, Kunming Institute of Botany, Chinese Academy of Sciences, China
| | - Huan Wang
- Key Laboratory of Economic Plants and Biotechnology, Kunming Institute of Botany, Chinese Academy of Sciences, China
| | - Wen-Hsuan Wu
- New Brunswick Graduate School, Rutgers University, New Brunswick, New Jersey, United States of America
| | - Michael A. Lawton
- Department of Plant Biology and Pathology, School of Environmental and Biological Sciences, Rutgers University, New Brunswick, New Jersey, United States of America
| | - Chunlin Long
- College of Life and Environmental Sciences, Minzu University of China, Beijing, China
- Key Laboratory of Economic Plants and Biotechnology, Kunming Institute of Botany, Chinese Academy of Sciences, China
- * E-mail: (RD); (CL)
| | - Rong Di
- Department of Plant Biology and Pathology, School of Environmental and Biological Sciences, Rutgers University, New Brunswick, New Jersey, United States of America
- * E-mail: (RD); (CL)
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22
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Kakani EG, Trakala M, Drosopoulou E, Mavragani-Tsipidou P, Mathiopoulos KD. Genomic structure, organization and localization of the acetylcholinesterase locus of the olive fruit fly, Bactrocera oleae. BULLETIN OF ENTOMOLOGICAL RESEARCH 2013; 103:36-47. [PMID: 22967668 DOI: 10.1017/s0007485312000478] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Acetylcholinesterase (AChE), encoded by the ace gene, is a key enzyme of cholinergic neurotransmission. Insensitive acetylcholinesterase (AChE) has been shown to be responsible for resistance to OPs and CBs in a number of arthropod species, including the most important pest of olives trees, the olive fruit fly Bactrocera oleae. In this paper, the organization of the B. oleae ace locus, as well as the structural and functional features of the enzyme, are determined. The organization of the gene was deduced by comparison to the ace cDNA sequence of B. oleae and the organization of the locus in Drosophila melanogaster. A similar structure between insect ace gene has been found, with conserved exon-intron positions and junction sequences. The B. oleae ace locus extends for at least 75 kb, consists of ten exons with nine introns and is mapped to division 34 of the chromosome arm IIL. Moreover, according to bioinformatic analysis, the Bo AChE exhibits all the common features of the insect AChE. Such structural and functional similarity among closely related AChE enzymes may implicate similarities in insecticide resistance mechanisms.
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Affiliation(s)
- E G Kakani
- Department of Biochemistry and Biotechnology, University of Thessaly, Greece
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Abstract
Caenorhabditis elegans locomotion is a stereotyped behavior that is ideal for genetic analysis. We integrated video microscopy, image analysis algorithms, and fluid mechanics principles to describe the C. elegans swim gait. Quantification of body shapes and external hydrodynamics and model-based estimates of biomechanics reveal that mutants affecting similar biological processes exhibit related patterns of biomechanical differences. Therefore, biomechanical profiling could be useful for predicting the function of previously unstudied motility genes.
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Jones OAH, Swain SC, Svendsen C, Griffin JL, Sturzenbaum SR, Spurgeon DJ. Potential new method of mixture effects testing using metabolomics and Caenorhabditis elegans. J Proteome Res 2012; 11:1446-53. [PMID: 22175231 DOI: 10.1021/pr201142c] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The development of superior tools for molecular and computational biology in recent years has provided an opportunity for the creation of faster toxicological screens that are relevant for, but do not rely on, mammalian systems. In this study, NMR spectroscopy and GC-MS based metabolomics have been used in conjunction with multivariate statistics to examine the metabolic changes in the nematode Caenorhabditis elegans following exposure to different concentrations of the heavy metal nickel, the pesticide chlorpyrifos, and their mixture. Novel metabolic profiles were associated with both exposure and dose level. The biochemical responses were more closely matched when exposure was at the same effect level, even for different chemicals, than when exposure was for different levels of the same chemical (e.g., low versus high dose). Responses to the mixture reflected the contribution of the chemicals to the overall exposure. In common with the metabolic responses of several other species exposed to the same chemicals, we observed changes in branch chain amino acids and tricarboxylic acid cycle intermediates. These results form the basis for a rapid and economically viable toxicity test that defines the molecular effects of pollution/toxicant exposure in a manner that is relevant to higher vertebrates.
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Affiliation(s)
- Oliver A H Jones
- The Sanger Building, Department of Biochemistry, 80 Tennis Court Road, University of Cambridge , Cambridge, CB2 1GA, UK.
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Pezzementi L, Krejci E, Chatonnet A, Selkirk ME, Matthews JB. A tetrameric acetylcholinesterase from the parasitic nematode Dictyocaulus viviparus associates with the vertebrate tail proteins PRiMA and ColQ. Mol Biochem Parasitol 2011; 181:40-8. [PMID: 22027027 DOI: 10.1016/j.molbiopara.2011.10.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2011] [Revised: 09/26/2011] [Accepted: 10/11/2011] [Indexed: 10/16/2022]
Abstract
Dictyocaulus viviparus causes a serious lung disease of cattle. Similar to other parasitic nematodes, D. viviparus possesses several acetylcholinesterase (AChE) genes, one of which encodes a putative neuromuscular AChE, which contains a tryptophan (W) amphiphilic tetramerization (WAT) domain at its C-terminus. In the current study, we describe the biochemical characterization of a recombinant version of this WAT domain-containing AChE. To assess if the WAT domain is biologically functional, we investigated the association of the recombinant enzyme with the vertebrate tail proteins, proline-rich membrane anchor (PRiMA) and collagen Q (ColQ), as well as the synthetic polypeptide poly-l-proline. The results indicate that the recombinant enzyme hydrolyzes acetylthiocholine preferentially and exhibits inhibition by excess substrate, a characteristic of AChEs but not butyrylcholinesterases (BChEs). The enzyme is inhibited by the AChE inhibitor, BW284c51, but not by the BChE inhibitors, ethopropazine or iso-OMPA. The enzyme is able to assemble into monomeric (G(1)), dimeric (G(2)), and tetrameric (G(4)) globular forms and can also associate with PRiMA and ColQ, which contain proline-rich attachment domains (PRADs). This interaction is likely to be mediated via WAT-PRAD interactions, as the enzyme also assembles into tetramers with the synthetic polypeptide poly-l-proline. These interactions are typical of AChE(T) subunits. This is the first demonstration of an AChE(T) from a parasitic nematode that can assemble into heterologous forms with vertebrate proteins that anchor the enzyme in cholinergic synapses. We discuss the implications of our results for this particular host/parasite system and for the evolution of AChE.
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Affiliation(s)
- Leo Pezzementi
- Department of Biology, Birmingham-Southern College, Birmingham, AL 35254, USA.
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26
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Kang JS, Lee DW, Koh YH, Lee SH. A soluble acetylcholinesterase provides chemical defense against xenobiotics in the pinewood nematode. PLoS One 2011; 6:e19063. [PMID: 21556353 PMCID: PMC3083410 DOI: 10.1371/journal.pone.0019063] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2011] [Accepted: 03/15/2011] [Indexed: 12/15/2022] Open
Abstract
The pinewood nematode genome encodes at least three distinct acetylcholinesterases (AChEs). To understand physiological roles of the three pinewood nematode AChEs (BxACE-1, BxACE-2, and BxACE-3), BxACE-3 in particular, their tissue distribution and inhibition profiles were investigated. Immunohistochemistry revealed that BxACE-1 and BxACE-2 were distributed in neuronal tissues. In contrast, BxACE-3 was detected from some specific tissues and extracted without the aid of detergent, suggesting its soluble nature unlike BxACE-1 and BxACE-2. When present together, BxAChE3 significantly reduced the inhibition of BxACE-1 and BxACE-2 by cholinesterase inhibitors. Knockdown of BxACE-3 by RNA interference significantly increased the toxicity of three nematicidal compounds, supporting the protective role of BxACE-3 against chemicals. In summary, BxACE-3 appears to have a non-neuronal function of chemical defense whereas both BxACE-1 and BxACE-2 have classical neuronal function of synaptic transmission.
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Affiliation(s)
- Jae Soon Kang
- Research Institute for Agriculture and Life Science, Seoul National University, Seoul, Korea
| | - Dae-Weon Lee
- Ilsong Institute of Life Science, Hallym University, Anyang, Korea
| | - Young Ho Koh
- Ilsong Institute of Life Science, Hallym University, Anyang, Korea
| | - Si Hyeock Lee
- Research Institute for Agriculture and Life Science, Seoul National University, Seoul, Korea
- Department of Agricultural Biotechnology, Seoul National University, Seoul, Korea
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Kang JS, Lee DW, Choi JY, Je YH, Koh YH, Lee SH. Three acetylcholinesterases of the pinewood nematode, Bursaphelenchus xylophilus: insights into distinct physiological functions. Mol Biochem Parasitol 2010; 175:154-61. [PMID: 21074580 DOI: 10.1016/j.molbiopara.2010.11.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2010] [Revised: 11/04/2010] [Accepted: 11/04/2010] [Indexed: 11/19/2022]
Abstract
Acetylcholinesterase (AChE) plays a key role in postsynaptic transmission in most animals. Nematodes encode multiple AChEs, implying its functional diversity. To explore physiological functions of multiple AChEs, three distinct AChEs (BxACE-1, BxACE-2, and BxACE-3) were identified and characterized from the pinewood nematode. Sequencing comparison with Torpedo AChE and Caenorhabditis elegans ACEs identified choline-binding site, catalytic triad functional site, three internal disulfide bonds and aromatic residues for the catalytic gorge. Transcriptional profiling by quantitative real-time PCR revealed that BxACE-3 is more actively transcribed than BxACE-1 (2-3 times) and BxACE-2 (9-18 times) in both propagative and dispersal stages. The three BxACEs were functionally expressed using baculovirus system. Kinetic analysis of in vitro-expressed BxACEs revealed that the substrate specificity was highest in BxACE-1 whereas the catalytic efficiency was highest in BxACE-2. In inhibition assay, BxACE-3 showed the lowest inhibition rate. Taken together, it appears that both BxACE-1 and BxACE-2 play common but non-overlapping roles in synaptic transmission, whereas BxACE-3 may have non-neuronal functions. The current findings should provide valuable insights into the evolutionary process and various physiological roles of AChE.
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Affiliation(s)
- Jae Soon Kang
- Research Institute for Agriculture and Life Science, Seoul National University, Seoul, Republic of Korea
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28
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Old and new questions about cholinesterases. Chem Biol Interact 2008; 175:30-44. [DOI: 10.1016/j.cbi.2008.04.039] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2007] [Revised: 04/25/2008] [Accepted: 04/28/2008] [Indexed: 01/21/2023]
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Effects of genetic mutations and chemical exposures on Caenorhabditis elegans feeding: evaluation of a novel, high-throughput screening assay. PLoS One 2007; 2:e1259. [PMID: 18060055 PMCID: PMC2092392 DOI: 10.1371/journal.pone.0001259] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2007] [Accepted: 10/29/2007] [Indexed: 11/28/2022] Open
Abstract
Background Government agencies have defined a need to reduce, refine or replace current mammalian-based bioassays with testing methods that use alternative species. Invertebrate species, such as Caenorhabditis elegans, provide an attractive option because of their short life cycles, inexpensive maintenance, and high degree of evolutionary conservation with higher eukaryotes. The C. elegans pharynx is a favorable model for studying neuromuscular function, and the effects of chemicals on neuromuscular activity, i.e., feeding. Current feeding methodologies, however, are labor intensive and only semi-quantitative. Methodology/Principal Findings Here a high-throughput assay is described that uses flow cytometry to measure C. elegans feeding by determining the size and intestinal fluorescence of hundreds of nematodes after exposure to fluorescent-labeled microspheres. This assay was validated by quantifying fluorescence in feeding-defective C. elegans (eat mutants), and by exposing wild-type nematodes to the neuroactive compounds, serotonin and arecoline. The eat mutations previously determined to cause slow pumping rates exhibited the lowest feeding levels with our assay. Concentration-dependent increases in feeding levels after serotonin exposures were dependent on food availability, while feeding levels decreased in arecoline-exposed nematodes regardless of the presence of food. The effects of the environmental contaminants, cadmium chloride and chlorpyrifos, on wild-type C. elegans feeding were then used to demonstrate an application of the feeding assay. Cadmium exposures above 200 µM led to a sharp drop in feeding levels. Feeding of chlorpyrifos-exposed nematodes decreased in a concentration-dependent fashion with an EC50 of 2 µM. Conclusions/Significance The C. elegans fluorescence microsphere feeding assay is a rapid, reliable method for the assessment of neurotoxic effects of pharmaceutical drugs, industrial chemicals or environmental agents. This assay may also be applicable to large scale genetic or RNAi screens used to identify genes that are necessary for the development or function of the pharynx or other neuromuscular systems.
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Badiou A, Brunet JL, Belzunces LP. Existence of two membrane-bound acetylcholinesterases in the honey bee head. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2007; 66:122-134. [PMID: 17966129 DOI: 10.1002/arch.20204] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Two acetylcholinesterase (EC 3.1.1.7) membrane forms AChE(m1) and AChE(m2), have been characterised in the honey bee head. They can be differentiated by their ionic properties: AChE(m1) is eluted at 220 mM NaCl whereas AChE(m2) is eluted at 350 mM NaCl in anion exchange chromatography. They also present different thermal stabilities. Previous processing such as sedimentation, phase separation, and extraction procedures do not affect the presence of the two forms. Unlike AChE(m1), AChE(m2) presents reversible chromatographic elution properties, with a shift between 350 to 220 mM NaCl, depending on detergent conditions. Purification by affinity chromatography does not abolish the shift of the AChE(m2) elution. The similar chromatographic behaviour of soluble AChE strongly suggests that the occurrence of the two membrane forms is not due to the membrane anchor. The two forms have similar sensitivities to eserine and BW284C51. They exhibit similar electrophoretic mobilities and present molecular masses of 66 kDa in SDS-PAGE and a sensitivity to phosphatidylinositol-specific phospholipase C in non-denaturing conditions, thus revealing the presence of a glycosyl-phosphatidylinositol anchor. We assume that bee AChE occurs in two distinct conformational states whose AChE(m2) apparent state is reversibly modulated by the Triton X-100 detergent into AChE(m1).
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Affiliation(s)
- Alexandra Badiou
- INRA, Laboratoire de Toxicologie Environnementale, UMR INRA-UAPV 406 Ecologie des Invertébrés, Avignon, France.
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Coutinho-Abreu IV, Balbino VQ, Valenzuela JG, Sonoda IV, Ramalho-Ortigão JM. Structural characterization of acetylcholinesterase 1 from the sand fly Lutzomyia longipalpis (Diptera: Psychodidae). JOURNAL OF MEDICAL ENTOMOLOGY 2007; 44:639-50. [PMID: 17695019 DOI: 10.1603/0022-2585(2007)44[639:scoaft]2.0.co;2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Acetylcholinesterase (AChE) plays a key role in cholinergic impulse transmission, and it is the target enzyme for organophosphorus and carbamate insecticides. Two genes, AceI and AceII, have been characterized from different insect species, and point mutations in either gene can lead to significant resistance to these classes of insecticides. In this report, we describe the partial characterization of the AceI gene from Lutzomyia longipalpis (Lutz & Neiva) (Diptera: Psychodidae), and we show that the possibility exists for the development of a resistant phenotype to organophosphates and carbamates in sand flies. Our results point to the presence of a single AceI gene in L. longipalpis (LlAce1) and that AChE activity is inhibited by organophosphorus at a concentration of 5 x 10(-5) M. Regarding insecticide resistance, analysis of the truncated LlAce1 cDNA suggests that a single missense mutation leading to a glycine-to-serine substitution at amino acid position 119 (G119S) may arise in L. longipalpis, similar to what has been detected in Anopheles gambiae s.s. Another missense mutation involved in resistant phenotypes, F331W, detected in Culex tritaeniorhynchus Giles, is less likely to occur in L. longipalpis, because it faces codon constraint in this sand fly species. Comparison of the three-dimensional structures of the deduced amino acid sequence of the truncated LLAChE1 with that of An. gambiae and Cx. tritaeniorhynchus also suggests that similar structural modifications due to the missense amino acid changes in the active site gorge are detected in all three insects.
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Affiliation(s)
- I V Coutinho-Abreu
- Laboratório de Genética Molecular Humana, Departamento de Genética, UFPE, Recife-PE, Brazil
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32
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Kim JI, Jung CS, Koh YH, Lee SH. Molecular, biochemical and histochemical characterization of two acetylcholinesterase cDNAs from the German cockroach Blattella germanica. INSECT MOLECULAR BIOLOGY 2006; 15:513-22. [PMID: 16907838 DOI: 10.1111/j.1365-2583.2006.00666.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Full length cDNAs encoding two acetylcholinesterases (AChEs; Bgace1 and Bgace2) were cloned and characterized from the German cockroach, Blattella germanica. Sequence analyses showed that both genes possess all the typical features of ace, and that Bgace1 is orthologous to the insect ace1 whereas Bgace2 is to the insect ace2. Transcript level of Bgace1 was significantly higher (c. 10 fold) than that of Bgace2 in all 11 tissues examined, suggesting that Bgace1 likely encodes a predominant AChE. Multiple AChE bands were identified by native polyacrylamide gel electrophoresis and isoelectricfocusing from various tissue preparations, among which ganglia produced distinct two major and two minor AChE bands, indicative of the presence of at least two active AChEs. B. germanica AChEs appeared to be mainly localized in the central nervous system as demonstrated by histochemical activity staining, together with quantitative analysis of Bgace transcripts. Fluorescence in situ hybridization of the 1st thoracic ganglion confirmed that Bgace1 is predominantly transcribed and further showed that its transcript is found in almost entire region of inter or motor neurones including the cell bodies and axonal/dendritic branches. Bgace2 transcript is found only in the subset of neurones, particularly in the cell body. In addition, certain neurones were observed to express Bgace1 only.
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Affiliation(s)
- J I Kim
- School of Agricultural Biotechnology, Seoul National University, Seoul, Korea
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33
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Fletcher SP, Geyer BC, Smith A, Evron T, Joshi L, Soreq H, Mor TS. Tissue distribution of cholinesterases and anticholinesterases in native and transgenic tomato plants. PLANT MOLECULAR BIOLOGY 2004; 55:33-43. [PMID: 15604663 DOI: 10.1007/s11103-004-0394-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Acetylcholinesterase, a major component of the central and peripheral nervous systems, is ubiquitous among multicellular animals, where its main function is to terminate synaptic transmission by hydrolyzing the neurotransmitter, acetylcholine. However, previous reports describe cholinesterase activities in several plant species and we present data for its presence in tomato plants. Ectopic expression of a recombinant form of the human enzyme and the expression pattern of the transgene and the accumulation of its product in transgenic tomato plants are described. Levels of acetylcholinesterase activity in different tissues are closely effected by and can be separated from alpha-tomatine, an anticholinesterase steroidal glycoalkaloid. The recombinant enzyme can also be separated from the endogenous cholinesterase activity by its subcellular localization and distinct biochemical properties. Our results provide evidence for the co-existence in tomato plants of both acetylcholinesterase activity and a steroidal glycoalkaloid with anticholinesterase activity and suggest spatial mutual exclusivity of these antagonistic activities. Potential functions, including roles in plant-pathogen interactions are discussed.
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Affiliation(s)
- Samuel P Fletcher
- School of Life Sciences and Arizona Biodesign Institute, Arizona State University, USA
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34
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Li F, Han Z. Mutations in acetylcholinesterase associated with insecticide resistance in the cotton aphid, Aphis gossypii Glover. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2004; 34:397-405. [PMID: 15041023 DOI: 10.1016/j.ibmb.2004.02.001] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2003] [Revised: 02/03/2004] [Accepted: 02/04/2004] [Indexed: 05/24/2023]
Abstract
Two acetylcholinesterase genes, Ace1 and Ace2, have been fully cloned and sequenced from both organophosphate-resistant and susceptible clones of cotton aphid. Comparison of both nucleic acid and deduced amino acid sequences revealed considerable nucleotide polymorphisms. Further study found that two mutations occurred consistently in all resistant aphids. The mutation F139L in Ace2 corresponding to F115S in Drosophila acetylcholinesterase might reduce the enzyme sensitivity and result in insecticide resistance. The other mutation A302S in Ace1 abutting the conserved catalytic triad might affect the activity and insecticide sensitivity of the enzyme. Phylogenetic analysis showed that insect acetylcholinesterases fall into two subgroups, of which Ace1 is the paralogous gene whereas Ace2 is the orthologous gene of Drosophila AChE. Both subgroups contain resistance-associated AChE genes. To avoid confusion in the future work, a nomenclature of insect AChE is also suggested in the paper.
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Affiliation(s)
- Fei Li
- Key Laboratory of Monitoring and Management of Plant Disease and Insects, Ministry of Agriculture, Nanjing Agricultural University, Nanjing 210095, Jiangsu province, PR China
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35
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Cole RD, Anderson GL, Williams PL. The nematode Caenorhabditis elegans as a model of organophosphate-induced mammalian neurotoxicity. Toxicol Appl Pharmacol 2004; 194:248-56. [PMID: 14761681 DOI: 10.1016/j.taap.2003.09.013] [Citation(s) in RCA: 103] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2003] [Accepted: 09/23/2003] [Indexed: 12/01/2022]
Abstract
Fifteen organic phosphate pesticides were tested by computer tracking for their acute behavioral toxicity with the nematode Caenorhabditis elegans. Thirteen of these 15 chemicals are used as insecticides and are anticholesterase agents. The other two chemicals are used as herbicides. EC50 values for each chemical were compared to the corresponding LD50 acute lethality value in rats and mice. Order of toxicity was found to be significantly correlated in comparisons of C. elegans to both rats and mice. Mechanistic investigations were conducted by assaying 8 of the 15 chemicals for anticholinesterase activity in C. elegans. Significant cholinesterase inhibition was confirmed for five chemicals that had displayed high behavioral toxicity, while three chemicals of low behavioral toxicity showed no significant decrease in cholinesterase activity. Toxicity for two chemicals that do not inhibit cholinesterase in mammals was linked to pH effects. Detailed comparison of individual chemicals and metabolic issues are discussed. These results have positive implications for the use of C. elegans as a mammalian neurological model and support the use of C. elegans in early rounds of chemical toxicity screening.
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Affiliation(s)
- Russell D Cole
- Department of Environmental Health Science, The University of Georgia, Athens, GA 30602-2102, USA
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36
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Ruvinsky I, Ruvkun G. Functional tests of enhancer conservation between distantly related species. Development 2003; 130:5133-42. [PMID: 12944426 DOI: 10.1242/dev.00711] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Expression patterns of orthologous genes are often conserved, even between distantly related organisms, suggesting that once established, developmental programs can be stably maintained over long periods of evolutionary time. Because many orthologous transcription factors are also functionally conserved, one possible model to account for homologous gene expression patterns, is conservation of specific binding sites within cis-regulatory elements of orthologous genes. If this model is correct, a cis-regulatory element from one organism would be expected to function in a distantly related organism. To test this hypothesis, we fused the green fluorescent protein gene to neuronal and muscular enhancer elements from a variety of Drosophila melanogaster genes, and tested whether these would activate expression in the homologous cell types in Caenorhabditis elegans. Regulatory elements from several genes directed appropriate expression in homologous tissue types, suggesting conservation of regulatory sites. However, enhancers of most Drosophila genes tested were not properly recognized in C. elegans, implying that over this evolutionary distance enough changes occurred in cis-regulatory sequences and/or transcription factors to prevent proper recognition of heterospecific enhancers. Comparisons of enhancer elements of orthologous genes between C. elegans and C. briggsae revealed extensive conservation, as well as specific instances of functional divergence. Our results indicate that functional changes in cis-regulatory sequences accumulate on timescales much shorter than the divergence of arthropods and nematodes, and that mechanisms other than conservation of individual binding sites within enhancer elements are responsible for the conservation of expression patterns of homologous genes between distantly related species.
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Affiliation(s)
- Ilya Ruvinsky
- Department of Molecular Biology, Massachusetts General Hospital and Department of Genetics, Harvard Medical School, Wellman 8, Boston, MA 02114, USA
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37
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Bentley GN, Jones AK, Agnew A. Mapping and sequencing of acetylcholinesterase genes from the platyhelminth blood fluke Schistosoma. Gene 2003; 314:103-12. [PMID: 14527722 DOI: 10.1016/s0378-1119(03)00709-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Acetylcholinesterase (AChE) on the surface of the parasitic blood fluke Schistosoma is the likely target for schistosomicidal anticholinesterases. Determination of the molecular structure of this drug target is key for the development of improved anticholinesterase drugs and potentially a novel vaccine. We have recently cloned the cDNA encoding the AChE from the human parasite Schistosoma haematobium and succeeded in expressing functional recombinant protein. We now describe the cloning and molecular characterisation of homologues from two other schistosome species-Schistosoma mansoni and Schistosoma bovis, which are important parasites of man and cattle, respectively, but which differ in their sensitivity to the therapeutic anticholinesterase metrifonate. Comparison of the deduced amino acid sequences revealed that the AChE from all three species posses a high degree of identity, with conservation of all of the residues known to be important for substrate binding and catalytic activity. Also conserved is a unique C-terminal domain which is unusual in that it lacks the consensus for GPI modification, even though the native protein is considered to be GPI-anchored. We have also established the AChE gene structures for all three species and cloned the complete gene for S. haematobium AChE. The gene structure is relatively complex, comprising nine coding exons; the location of the splice sites is identical in all three species, but the size of the introns varies considerably. The two C-terminal splicing sites that are conserved in all species are also present in Schistosoma, but a third C-terminal conserved splicing site which is located 11-13 amino acids upstream of the histidine of the catalytic triad in all invertebrate AChE genes characterised to date is absent. We discuss our findings in the context of the molecular phylogeny of the AChE genes and the potential application to the control of schistosomiasis.
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Affiliation(s)
- Geoffrey N Bentley
- The School of Biology, University of Leeds, West Yorkshire, LS2 9JT, Leeds, UK.
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38
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Combes D, Fedon Y, Toutant JP, Arpagaus M. Multiple ace genes encoding acetylcholinesterases of Caenorhabditis elegans have distinct tissue expression. Eur J Neurosci 2003; 18:497-512. [PMID: 12911746 DOI: 10.1046/j.1460-9568.2003.02749.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
ace-1 and ace-2 genes encoding acetylcholinesterase in the nematode Caenorhabditis elegans present 35% identity in coding sequences but no homology in noncoding regions (introns, 5'- and 3'-untranslated regions). A 5'-region of ace-2 was defined by rescue of ace-1;ace-2 mutants. When green fluorescent protein (GFP) expression was driven by this regulatory region, the resulting pattern was distinct from that of ace-1. This latter gene is expressed in all body-wall and vulval muscle cells (Culetto et al., 1999), whereas ace-2 is expressed almost exclusively in neurons. ace-3 and ace-4 genes are located in close proximity on chromosome II (Combes et al., 2000). These two genes were first transcribed in vivo as a bicistronic messenger and thus constitute an ace-3;ace-4 operon. However, there was a very low level of monocistronic mRNA of ace-4 (the upstream gene) in vivo, and no ACE-4 enzymatic activity was ever detected. GFP expression driven by a 5' upstream region of the ace-3;ace-4 operon was detected in several muscle cells of the pharynx (pm3, pm4, pm5 and pm7) and in the two canal associated neurons (CAN cells). A dorsal row of body-wall muscle cells was intensively labelled in larval stages but no longer detected in adults. The distinct tissue-specific expression of ace-1, ace-2 and ace-3 (coexpressed only in pm5 cells) indicates that ace genes are not redundant.
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Affiliation(s)
- Didier Combes
- Différenciation cellulaire et croissance, INRA, 2 place Viala, 34060 Montpellier cedex 1, France
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Weill M, Fort P, Berthomieu A, Dubois MP, Pasteur N, Raymond M. A novel acetylcholinesterase gene in mosquitoes codes for the insecticide target and is non-homologous to the ace gene in Drosophila. Proc Biol Sci 2002; 269:2007-16. [PMID: 12396499 PMCID: PMC1691131 DOI: 10.1098/rspb.2002.2122] [Citation(s) in RCA: 171] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Acetylcholinesterase (AChE) is the target of two major insecticide families, organophosphates (OPs) and carbamates. AChE insensitivity is a frequent resistance mechanism in insects and responsible mutations in the ace gene were identified in two Diptera, Drosophila melanogaster and Musca domestica. However, for other insects, the ace gene cloned by homology with Drosophila does not code for the insensitive AChE in resistant individuals, indicating the existence of a second ace locus. We identified two AChE loci in the genome of Anopheles gambiae, one (ace-1) being a new locus and the other (ace-2) being homologous to the gene previously described in Drosophila. The gene ace-1 has no obvious homologue in the Drosophila genome and was found in 15 mosquito species investigated. In An. gambiae, ace-1 and ace-2 display 53% similarity at the amino acid level and an overall phylogeny indicates that they probably diverged before the differentiation of insects. Thus, both genes are likely to be present in the majority of insects and the absence of ace-1 in Drosophila is probably due to a secondary loss. In one mosquito (Culex pipiens), ace-1 was found to be tightly linked with insecticide resistance and probably encodes the AChE OP target. These results have important implications for the design of new insecticides, as the target AChE is thus encoded by distinct genes in different insect groups, even within the Diptera: ace-2 in at least the Drosophilidae and Muscidae and ace-1 in at least the Culicidae. Evolutionary scenarios leading to such a peculiar situation are discussed.
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Affiliation(s)
- Mylène Weill
- Institut des Sciences de l'Evolution (UMR 5554), CC 065, Université Montpellier II, F-34095 Montpellier cedex 05, France.
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