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De Rouck S, İnak E, Dermauw W, Van Leeuwen T. A review of the molecular mechanisms of acaricide resistance in mites and ticks. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2023; 159:103981. [PMID: 37391089 DOI: 10.1016/j.ibmb.2023.103981] [Citation(s) in RCA: 29] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 05/12/2023] [Accepted: 06/11/2023] [Indexed: 07/02/2023]
Abstract
The Arachnida subclass of Acari comprises many harmful pests that threaten agriculture as well as animal health, including herbivorous spider mites, the bee parasite Varroa, the poultry mite Dermanyssus and several species of ticks. Especially in agriculture, acaricides are often used intensively to minimize the damage they inflict, promoting the development of resistance. Beneficial predatory mites used in biological control are also subjected to acaricide selection in the field. The development and use of new genetic and genomic tools such as genome and transcriptome sequencing, bulked segregant analysis (QTL mapping), and reverse genetics via RNAi or CRISPR/Cas9, have greatly increased our understanding of the molecular genetic mechanisms of resistance in Acari, especially in the spider mite Tetranychus urticae which emerged as a model species. These new techniques allowed to uncover and validate new resistance mutations in a larger range of species. In addition, they provided an impetus to start elucidating more challenging questions on mechanisms of gene regulation of detoxification associated with resistance.
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Affiliation(s)
- Sander De Rouck
- Laboratory of Agrozoology, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000, Ghent, Belgium
| | - Emre İnak
- Laboratory of Agrozoology, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000, Ghent, Belgium; Department of Plant Protection, Faculty of Agriculture, Ankara University, Dıskapı, 06110, Ankara, Turkiye
| | - Wannes Dermauw
- Laboratory of Agrozoology, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000, Ghent, Belgium; Flanders Research Institute for Agriculture, Fisheries and Food (ILVO), Plant Sciences Unit, 9820 Merelbeke, Belgium
| | - Thomas Van Leeuwen
- Laboratory of Agrozoology, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000, Ghent, Belgium.
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2
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Bishop RP, Githaka NW, Bazarusanga T, Bhushan C, Biguezoton A, Vudriko P, Muhanguzi D, Tumwebaze M, Bosco TJ, Shacklock C, Kiama J, Madder M, Maritz-Olivier C, Zhao W, Maree F, Majekodunmi AO, Halos L, Jongejan F, Evans A. Control of ticks and tick-borne diseases in Africa through improved diagnosis and utilisation of data on acaricide resistance. Parasit Vectors 2023; 16:224. [PMID: 37415211 DOI: 10.1186/s13071-023-05803-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Accepted: 05/08/2023] [Indexed: 07/08/2023] Open
Abstract
A meeting, sponsored by the Bill and Melinda Gates Foundation (BMGF) and organised by Clinglobal, was held at The International Livestock Research Institute (ILRI) in Nairobi, Kenya, from 19th - to 21st October 2022. The meeting assembled a unique group of experts on tick control in Africa. Academia, international agencies (FAO and ILRI), the private Animal Health sector and government veterinary services were represented. The significant outcomes included: (i) a shared commitment to standardisation and improvement of acaricide resistance bioassay protocols, particularly the widely used larval packet test (LPT); (ii) development of novel molecular assays for detecting acaricide resistance; (3) creation of platforms for disseminating acaricide resistance data to farmers, veterinary service providers and veterinary authorities to enable more rational evidence-based control of livestock ticks. Implementation of enhanced control will be facilitated by several recently established networks focused on control of parasites in Africa and globally, whose activities were presented at the meeting. These include a newly launched community of practice on management of livestock ticks, coordinated by FAO, an African module of the World Association for the Advancement of Veterinary Parasitology (WAAVP-AN) and the MAHABA (Managing Animal Health and Acaricides for a Better Africa) initiative of Elanco Animal Health.
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Affiliation(s)
| | | | | | | | | | - Patrick Vudriko
- Research Centre for Tropical Diseases and Vector Control (RTC) Makerere University, Kampala, Uganda
| | - Dennis Muhanguzi
- Molecular and Computational Biology Research Group, Makerere University, Kampala, Uganda
| | - Maria Tumwebaze
- Research Centre for Tropical Diseases and Vector Control (RTC) Makerere University, Kampala, Uganda
| | | | | | | | | | - Christine Maritz-Olivier
- Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, South Africa
| | - Weining Zhao
- United Nations Food and Agriculture Organisation, Rome, Italy
| | | | - Ayodele O Majekodunmi
- Emergency Centre for Transboundary Diseases (ECTAD), Food and Agriculture Organisation of the United Nations, Rome, Italy
| | - Lenaig Halos
- Bill and Melinda Gates Foundation, Seattle, WA, USA
| | - Frans Jongejan
- United Nations Food and Agriculture Organisation, Rome, Italy
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3
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Waldman J, Klafke GM, Tirloni L, Logullo C, da Silva Vaz I. Putative target sites in synganglion for novel ixodid tick control strategies. Ticks Tick Borne Dis 2023; 14:102123. [PMID: 36716581 PMCID: PMC10033424 DOI: 10.1016/j.ttbdis.2023.102123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 12/23/2022] [Accepted: 01/07/2023] [Indexed: 01/21/2023]
Abstract
Acaricide resistance is a global problem that has impacts worldwide. Tick populations with broad resistance to all commercially available acaricides have been reported. Since resistance selection in ticks and their role in pathogen transmission to animals and humans result in important economic and public health burden, it is essential to develop new strategies for their control (i.e., novel chemical compounds, vaccines, biological control). The synganglion is the tick central nervous system and it is responsible for synthesizing and releasing signaling molecules with different physiological functions. Synganglion proteins are the targets of the majority of available acaricides. In this review we provide an overview of the mode-of-action and resistance mechanisms against neurotoxic acaricides in ticks, as well as putative target sites in synganglion, as a supporting tool to identify new target proteins and to develop new strategies for tick control.
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Affiliation(s)
- Jéssica Waldman
- Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Guilherme Marcondes Klafke
- Instituto de Pesquisas Veterinárias Desidério Finamor - Centro de Pesquisa em Saúde Animal, Secretaria da Agricultura, Pecuária e Desenvolvimento Rural, Eldorado do Sul, RS, Brazil; Instituto Nacional de Ciência e Tecnologia - Entomologia Molecular, Rio de Janeiro, RJ, Brazil
| | - Lucas Tirloni
- Laboratory of Bacteriology, Tick-Pathogen Transmission Unit, National Institute of Allergy and Infectious Diseases, Hamilton, MT, USA
| | - Carlos Logullo
- Instituto Nacional de Ciência e Tecnologia - Entomologia Molecular, Rio de Janeiro, RJ, Brazil; Laboratório de Bioquímica de Artrópodes Hematófagos, IBqM, Universidade Federal do Rio de Janeiro, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Itabajara da Silva Vaz
- Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil; Instituto Nacional de Ciência e Tecnologia - Entomologia Molecular, Rio de Janeiro, RJ, Brazil; Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
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Temeyer KB, Schlechte KG, Gross AD, Lohmeyer KH. Identification, Baculoviral Expression, and Biochemical Characterization of a Novel Cholinesterase of Amblyomma americanum (Acari: Ixodidae). Int J Mol Sci 2023; 24:ijms24097681. [PMID: 37175388 PMCID: PMC10178864 DOI: 10.3390/ijms24097681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 04/17/2023] [Accepted: 04/20/2023] [Indexed: 05/15/2023] Open
Abstract
A cDNA encoding a novel cholinesterase (ChE, EC 3.1.1.8) from the larvae of Amblyomma americanum (Linnaeus) was identified, sequenced, and expressed in Sf21 insect cell culture using the baculoviral expression vector pBlueBac4.5/V5-His. The open reading frame (1746 nucleotides) of the cDNA encoded 581 amino acids beginning with the initiation codon. Identical cDNA sequences were amplified from the total RNA of adult tick synganglion and salivary gland, strongly suggesting expression in both tick synganglion and saliva. The recombinant enzyme (rAaChE1) was highly sensitive to eserine and BW284c51, relatively insensitive to tetraisopropyl pyrophosphoramide (iso-OMPA) and ethopropazine, and hydrolyzed butyrylthiocholine (BuTCh) 5.7 times as fast as acetylthiocholine (ATCh) at 120 µM, with calculated KM values for acetylthiocholine (ATCh) and butyrylthiocholine of 6.39 µM and 14.18 µM, respectively. The recombinant enzyme was highly sensitive to inhibition by malaoxon, paraoxon, and coroxon in either substrate. Western blots using polyclonal rabbit antibody produced by immunization with a peptide specific for rAaChE1 exhibited reactivity in salivary and synganglial extract blots, indicating the presence of AaChE1 antigenic protein. Total cholinesterase activities of synganglial or salivary gland extracts from adult ticks exhibited biochemical properties very different from the expressed rAaACh1 enzyme, evidencing the substantial presence of additional cholinesterase activities in tick synganglion and saliva. The biological function of AaChE1 remains to be elucidated, but its presence in tick saliva is suggestive of functions in hydrolysis of cholinergic substrates present in the large blood mean and potential involvement in the modulation of host immune responses to tick feeding and introduced pathogens.
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Affiliation(s)
- Kevin B Temeyer
- Knipling-Bushland U.S. Livestock Insects Research Laboratory and Arthropod Genomics Center, USDA-ARS, 2700 Fredericksburg Road, Kerrville, TX 78028, USA
| | - Kristie G Schlechte
- Knipling-Bushland U.S. Livestock Insects Research Laboratory and Arthropod Genomics Center, USDA-ARS, 2700 Fredericksburg Road, Kerrville, TX 78028, USA
| | - Aaron D Gross
- Molecular Physiology and Toxicology Laboratory, Department of Entomology (MC 0390), Virginia Polytechnic Institute and State University, Latham Hall (Rm 307), 220 Ag Quad Lane, Blacksburg, VA 24061, USA
| | - Kimberly H Lohmeyer
- Knipling-Bushland U.S. Livestock Insects Research Laboratory and Arthropod Genomics Center, USDA-ARS, 2700 Fredericksburg Road, Kerrville, TX 78028, USA
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Kim S, Yoon KA, Cho S, Lee J, Lim Y, Lee SH. Molecular and kinetic properties of three acetylcholinesterases in the Varroa mite, Varroa destructor. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2022; 188:105277. [PMID: 36464382 DOI: 10.1016/j.pestbp.2022.105277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 11/01/2022] [Indexed: 06/17/2023]
Abstract
The Varroa mite, Varroa destructor, poses one of the most serious threats to honey bees worldwide. Although coumaphos, an anticholinesterase pesticide, is widely used for varroa mite control, little information is available on the properties of Varroa mite acetylcholinesterases (VdAChEs). In this study, three putative VdAChEs were annotated and named VdAChE1, VdAChE2, and VdAChE3. All VdAChEs possessed most of the functionally important signature domains, suggesting that they are catalytically active. Phylogenetic analysis revealed that VdAChE1 was clustered into a clade containing most arthropod AChE1s, whereas VdAChE2 and VdAChE3 formed a unique clade with other arachnid AChEs. VdAChE1 was determined to be membrane-anchored, but both VdAChE2 and VdAChE3 are soluble, as judged by electrophoresis in conjunction with western blotting. Tissue-specific transcription profiling revealed that VdAChE1 was most predominantly expressed in the synganglion. In contrast, VdAChE2 was most predominantly expressed in the legs and cuticle. VdAChE3 showed negligible expression levels in all the tissues examined. In a kinetic analysis using recombinant VdAChEs, VdAChE1 exhibited the highest catalytic efficiency, followed by VdAChE2 and VdAChE3. Inhibition experiments revealed that VdAChE1 was most sensitive to all tested inhibitors. Taken together, VdAChE1 appears to be the major synaptic enzyme with a more toxicological relevance, whereas VdAChE2 is involved in other noncatalytic functions, including chemical defense against xenobiotics. Current findings contribute to a more detailed understanding of the evolutionary and functional traits of VdAChEs and to the design of novel anticholinesterase varroacides.
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Affiliation(s)
- Sanghyeon Kim
- Research Institute of Agriculture and Life Sciences, Seoul National University, 1, Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Kyungjae Andrew Yoon
- Research Institute of Agriculture and Life Sciences, Seoul National University, 1, Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - SuSie Cho
- Entomology Program, Department of Agricultural Biotechnology, Seoul National University, 1, Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Joonhee Lee
- Entomology Program, Department of Agricultural Biotechnology, Seoul National University, 1, Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Youngcheon Lim
- Entomology Program, Department of Agricultural Biotechnology, Seoul National University, 1, Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Si Hyeock Lee
- Research Institute of Agriculture and Life Sciences, Seoul National University, 1, Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea; Entomology Program, Department of Agricultural Biotechnology, Seoul National University, 1, Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea.
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Cerqueira APM, Santos MDC, dos Santos Júnior MC, Botura MB. Molecular targets for the development of new acaricides against Rhipicephalus microplus: a review. Parasitology 2022; 149:1019-1026. [PMID: 35514112 PMCID: PMC11010478 DOI: 10.1017/s0031182022000506] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2022] [Revised: 04/06/2022] [Accepted: 04/06/2022] [Indexed: 11/06/2022]
Abstract
The cattle tick Rhipicephalus microplus is an ectoparasite with high economic importance to bovine culture, mainly in tropical and subtropical regions. The resistance of the tick from the commercial acaricides has hindered its control, thus motivating the search for new strategies. The purpose of this study was to perform a critical review about the main molecular targets of R. microplus that are useful for the discovery of new acaricides. Bibliographic search was conducted in the databases PubMed, ScienceDirect and CAB Direct, using the following descriptors: ‘Rhipicephalus microplus’, ‘Boophilus microplus’, ‘molecular targets’ and ‘action’, published between 2010 and 2021. Out of the 212 publications identified, 17 articles were selected for study inclusion. This review described 14 molecular targets and among these 4 are targets from commercial acaricides. Most of them are enzymes to catalyse important reactions to tick survival, related to energetic metabolism, mechanisms of biotransformation and neurotransmission. The data will be helpful in the development of new more effective and selective acaricides.
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Affiliation(s)
- Amanda Ponce Morais Cerqueira
- Departamento de Biologia, Programa de Pós-Graduação em Biotecnologia, Universidade Estadual de Feira de Santana, Feira de Santana, BA, Brazil
| | - Matheus da Cunha Santos
- Departamento de Saúde, Universidade Estadual de Feira de Santana, Feira de Santana, BA, Brazil
| | | | - Mariana Borges Botura
- Departamento de Saúde, Universidade Estadual de Feira de Santana, Feira de Santana, BA, Brazil
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Malak N, Niaz S, Wadood A, Nasreen N, Ali I, Iqbal J, Swelum AA, Ezzat ahmed A, Alkahtani MA, Zając Z, Khan A. In silico approaches to develop herbal acaricides against R. (Boophilus) Microplus and In vitro Anti-Tick activities of selected medicinal plants. Saudi J Biol Sci 2022; 29:103302. [PMID: 35602870 PMCID: PMC9118158 DOI: 10.1016/j.sjbs.2022.103302] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 02/28/2022] [Accepted: 04/17/2022] [Indexed: 11/24/2022] Open
Abstract
In tropical and sub-tropical areas of the world the most damaging pest of the livestock sector are cattle tick, Rhipicephalus microplus. The current study was aimed to generate phytochemical derived acaricides to control Rhipicephalus microplus populations, to maintain livestock herd production, minimize economic losses and to reduce uses of man-made chemicals acaricides. To achieve this goal, Adult immersion and larval package test were used to determine the feasibility of Berberium lyceum and Tamarixa aphylla against Rhipicephalus microplus ticks. Further, an In silico technique was employed to discover biologically active substances from both plants using docking method. Berberium lyceum and Tamarixa aphylla exhibited a reasonably high fatal effect at 40.0 mg/L on egg laying (index of egg laying = 0.19 and 0.19) respectively, thus inhibiting the oviposition (49.5 and 45.1, respectively) and the larval mortality (97% and 93%, respectively). Further, we also used Chem-Draw ultra-software (v. 12.0.2.1076. 2010) to illustrate different structures of38 known bioactive phytochemicals which are discovered in the PubChem database and verify the hypothesis that tick inhibition was linked to acetylcholinesterase (AChE). Barbamunine and rutin from Berberium lyceum showed remarkable interaction with RmAChE1 active site residues with docking scores of -9.11 to -8.71 while phytol and dehydrodigallic acid from Tamarix aphylla showed comparable docking scores of -7.17 and -7.14 respectively against Rhipicephalus microplus acetylcholinesterase protein. Based on obtained result, we believe that Berberium lyceum and Tamarixa aphylla bioactive components could be potential candidates in the control and management of Rhipicephalus microplus and should be studied further as a supplement or replacement for synthetic acaricides.
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Affiliation(s)
- Nosheen Malak
- Department of Zoology, Abdul Wali Khan University Mardan, Toru Road, Sheikh Maltoon Town, Mardan 23200, Pakistan
| | - Sadaf Niaz
- Department of Zoology, Abdul Wali Khan University Mardan, Toru Road, Sheikh Maltoon Town, Mardan 23200, Pakistan
| | - Abdul Wadood
- Department of Biochemistry, Abdul Wali Khan University Mardan, Toru Road, Sheikh Maltoon Town, Mardan 23200, Pakistan
| | - Nasreen Nasreen
- Department of Zoology, Abdul Wali Khan University Mardan, Toru Road, Sheikh Maltoon Town, Mardan 23200, Pakistan
| | - Iftikhar Ali
- Center for Plant Science and Biodiversity, University of Swat 19201, Pakistan
| | - Javed Iqbal
- Department of Botany, Bacha Khan University, Charsadda, 24420, Khyber Pakhtunkhwa, Pakistan
| | - Ayman A Swelum
- Department of Theriogenology, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt
| | - Ahmed Ezzat ahmed
- Biology Department, College of Science, King Khalid University, 61413 Abha, Saudi Arabia
- Department of Theriogenology, Faculty of veterinary Medicine, South Valley University, 83523 Qena, Egypt
| | - Mohammed A. Alkahtani
- Biology Department, College of Science, King Khalid University, 61413 Abha, Saudi Arabia
| | - Zbigniew Zając
- Department of Biology and Parasitology, Medical University of Lublin, Radziwiłłowska 11 st., 20-080 Lublin, Poland
| | - Adil Khan
- Department of Zoology, Bacha Khan University, Charsadda, 24420, Khyber Pakhtunkhwa, Pakistan
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Waldman J, Xavier MA, Vieira LR, Logullo R, Braz GRC, Tirloni L, Ribeiro JMC, Veenstra JA, Silva Vaz ID. Neuropeptides in Rhipicephalus microplus and other hard ticks. Ticks Tick Borne Dis 2022; 13:101910. [PMID: 35121230 PMCID: PMC9477089 DOI: 10.1016/j.ttbdis.2022.101910] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Revised: 01/24/2022] [Accepted: 01/25/2022] [Indexed: 12/15/2022]
Abstract
The synganglion is the central nervous system of ticks and, as such, controls tick physiology. It does so through the production and release of signaling molecules, many of which are neuropeptides. These peptides can function as neurotransmitters, neuromodulators and/or neurohormones, although in most cases their functions remain to be established. We identified and performed in silico characterization of neuropeptides present in different life stages and organs of Rhipicephalus microplus, generating transcriptomes from ovary, salivary glands, fat body, midgut and embryo. Annotation of synganglion transcripts led to the identification of 32 functional categories of proteins, of which the most abundant were: secreted, energetic metabolism and oxidant metabolism/detoxification. Neuropeptide precursors are among the sequences over-represented in R. microplus synganglion, with at least 5-fold higher transcription compared with other stages/organs. A total of 52 neuropeptide precursors were identified: ACP, achatin, allatostatins A, CC and CCC, allatotropin, bursicon A/B, calcitonin A and B, CCAP, CCHamide, CCRFamide, CCH/ITP, corazonin, DH31, DH44, eclosion hormone, EFLamide, EFLGGPamide, elevenin, ETH, FMRFamide myosuppressin-like, glycoprotein A2/B5, gonadulin, IGF, inotocin, insulin-like peptides, iPTH, leucokinin, myoinhibitory peptide, NPF 1 and 2, orcokinin, proctolin, pyrokinin/periviscerokinin, relaxin, RYamide, SIFamide, sNPF, sulfakinin, tachykinin and trissin. Several of these neuropeptides have not been previously reported in ticks, as the presence of ETH that was first clearly identified in Parasitiformes, which include ticks and mites. Prediction of the mature neuropeptides from precursor sequences was performed using available information about these peptides from other species, conserved domains and motifs. Almost all neuropeptides identified are also present in other tick species. Characterizing the role of neuropeptides and their respective receptors in tick physiology can aid the evaluation of their potential as drug targets.
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Affiliation(s)
- Jéssica Waldman
- Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Marina Amaral Xavier
- Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Larissa Rezende Vieira
- Departamento de Bioquímica, Instituto de Química, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Raquel Logullo
- Departamento de Bioquímica, Instituto de Química, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Gloria Regina Cardoso Braz
- Departamento de Bioquímica, Instituto de Química, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil; Instituto Nacional de Ciência e Tecnologia - Entomologia Molecular, Rio de Janeiro, RJ, Brazil
| | - Lucas Tirloni
- Tick-Pathogen Transmission Unit, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, Hamilton, MT, USA
| | - José Marcos C Ribeiro
- Vector Biology Section, Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, Rockville, MD, USA
| | - Jan A Veenstra
- Institut de Neurosciences Cognitives et Intégratives d'Aquitaine, UMR 5287 CNRS, Université de Bordeaux, Bordeaux, France
| | - Itabajara da Silva Vaz
- Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil; Instituto Nacional de Ciência e Tecnologia - Entomologia Molecular, Rio de Janeiro, RJ, Brazil; Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
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9
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Elhachimi L, Van Leeuwen T, Dermauw W, Rogiers C, Valcárcel F, Olmeda AS, Khatat SE, Daminet S, Sahibi H, Duchateau L. Variation of diazinon and amitraz susceptibility of Hyalomma marginatum (Acari: Ixodidae) in the Rabat-Sale-Kenitra region of Morocco. Ticks Tick Borne Dis 2021; 13:101883. [PMID: 34894524 DOI: 10.1016/j.ttbdis.2021.101883] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Revised: 09/21/2021] [Accepted: 11/16/2021] [Indexed: 11/18/2022]
Abstract
In the present study, the acaricide susceptibility status of Hyalomma marginatum in Morocco was investigated in the Rabat-Sale-Kenitra region using the Larval Packet Test. The overall LC50 value for diazinon and amitraz was 115 ppm (95% CI: [104; 125]) and 22 ppm (95% CI: [21; 23]), respectively. The LC50 values varied significantly between the nine sampled locations (P<0.001) ranging from 75 ppm (95% CI: [65; 84]) in Ouelmes to 179 ppm (95% CI: [139; 201]) in Jorf El Melha for diazinon and from 18 ppm (95% CI: [15; 21]) in Skhirat to 28 ppm (95% CI: [24; 31]) in Ouelmes for amitraz. Sequencing of the target-site of diazinon, acetylcholinesterase 1 (AChE1), indicated that previously reported resistance mutations in AChE1 were absent in ticks from Jorf El Melha surviving 500 ppm diazinon. This study is the first report on the H. marginatum susceptibilty status to the most frequently used acaricides in Morocco and indicates that acaricide tick resistance is emerging.
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Affiliation(s)
- Latifa Elhachimi
- Département de parasitologie et santé publique, Institut Agronomique et Vétérinaire Hassan II, B.P. 6202 Rabat-Instituts, Morocco; Laboratory of Agrozoology, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium.
| | - Thomas Van Leeuwen
- Laboratory of Agrozoology, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium
| | - Wannes Dermauw
- Laboratory of Agrozoology, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium; Plant Sciences Unit, Flanders research institute for agriculture, fisheries and food (ILVO), Burg. Van Gansberghelaan 96, B-9820 Merelbeke, Belgium Ghent, Belgium
| | - Carolien Rogiers
- Biometrics Research Center, Faculty of Veterinary Medicine,Ghent University, Salisburylaan 133, B-9820 Merelbeke, Belgium
| | - Félix Valcárcel
- Grupo de Parasitología Animal, Animalario del Departamento de Reproducción Animal, INIA, 28040 Madrid, Spain
| | - Angeles Sonia Olmeda
- Departamento de Sanidad Animal, Facultad de Veterinaria, UCM, 28040 Madrid, Spain
| | - Sarah Elhamiani Khatat
- Department of Medicine, Surgery and Reproduction, Hassan II Institute of Agronomy and Veterinary Medicine, Rabat, Morocco
| | - Sylvie Daminet
- Small Animal Department, Faculty of Veterinary Medicine of Ghent University, Salisburylaan 133, B-9820 Merelbeke, Belgium
| | - Hamid Sahibi
- Département de parasitologie et santé publique, Institut Agronomique et Vétérinaire Hassan II, B.P. 6202 Rabat-Instituts, Morocco
| | - Luc Duchateau
- Biometrics Research Center, Faculty of Veterinary Medicine,Ghent University, Salisburylaan 133, B-9820 Merelbeke, Belgium
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Fular A, Sharma AK, Upadhaya D, Nandi A, Nagar G, Bisht N, Shakya M, Kumar S, Kumar S, Kumar R, Ghosh S. Evaluation of acaricidal resistance status of Rhipicephalus microplus ticks from the hilly state (Uttarakhand) of India and evaluation of efficacy of a natural formulation for the management of resistant ticks. EXPERIMENTAL & APPLIED ACAROLOGY 2021; 85:355-377. [PMID: 34766246 DOI: 10.1007/s10493-021-00677-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Accepted: 11/01/2021] [Indexed: 06/13/2023]
Abstract
The resistance status against deltamethrin, cypermethrin, coumaphos and ivermectin was assessed of Rhipicephalus microplus from five districts of Uttarakhand, through adult immersion test and larval packet test. The field isolates were highly resistant to deltamethrin (median resistance ratio [RR50] = 9.10-29.13-fold) followed by cypermethrin (2.23-3.55). Surprisingly the isolates were susceptible to coumaphos (0.34-3.17). Emerging resistance against ivermectin (1.55-3.27) was also observed in all the isolates. Elevated levels of esterases (enzyme ratio = 2.93-5.84-fold), glutathione S-transferases (5.10-10.06) and monooxygenases (1.68-4.02) in resistant fields isolates were highly correlated (47.4-86.0%) with the resistant factor (RR50) determined by bioassay. All the isolates except Uttarkashi possess mutation at the 190th position in domain II of the sodium channel gene. As a mitigation strategy an Ageratum conyzoides-based characterized natural formulation was tested against all the isolates and was found effective at the concentration of 10.1-11.5%. The possibility of using the natural formulation for the management of multi-acaricide resistant ticks is discussed.
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Affiliation(s)
- Ashutosh Fular
- Entomology Laboratory, Division of Parasitology, ICAR- Indian Veterinary Research Institute, Izatnagar, Bareilly, U.P., 243122, India
| | - Anil Kumar Sharma
- Entomology Laboratory, Division of Parasitology, ICAR- Indian Veterinary Research Institute, Izatnagar, Bareilly, U.P., 243122, India
| | - Deepak Upadhaya
- Entomology Laboratory, Division of Parasitology, ICAR- Indian Veterinary Research Institute, Izatnagar, Bareilly, U.P., 243122, India
| | - Abhijit Nandi
- Entomology Laboratory, Division of Parasitology, ICAR- Indian Veterinary Research Institute, Izatnagar, Bareilly, U.P., 243122, India
| | - Gaurav Nagar
- Entomology Laboratory, Division of Parasitology, ICAR- Indian Veterinary Research Institute, Izatnagar, Bareilly, U.P., 243122, India
| | - Nisha Bisht
- Entomology Laboratory, Division of Parasitology, ICAR- Indian Veterinary Research Institute, Izatnagar, Bareilly, U.P., 243122, India
| | - Mukesh Shakya
- Department of Parasitology, College of Veterinary Science and Animal Husbandry, Rewa, Madhya Pradesh, India
| | - Sachin Kumar
- Entomology Laboratory, Division of Parasitology, ICAR- Indian Veterinary Research Institute, Izatnagar, Bareilly, U.P., 243122, India
| | - Satyanshu Kumar
- ICAR-Directorate of Medicinal and Aromatic Plants Research, Boriavi, Anand, Gujarat, 387310, India
| | - Rajesh Kumar
- Division of Agricultural Chemicals, ICAR- Indian Agricultural Research Institute, New Delhi, 110012, India
| | - Srikant Ghosh
- Entomology Laboratory, Division of Parasitology, ICAR- Indian Veterinary Research Institute, Izatnagar, Bareilly, U.P., 243122, India.
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Comparative susceptibility of Rhipicephalus microplus collected from the northern state of India to coumaphos, malathion, deltamethrin, ivermectin, and fipronil. Trop Anim Health Prod 2021; 53:460. [PMID: 34542704 DOI: 10.1007/s11250-021-02886-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Accepted: 09/10/2021] [Indexed: 10/20/2022]
Abstract
The chemical-based tick management method is gradually losing its clutch due to the establishment of resistant ticks. For development of region-specific tick management strategies, the present study was aimed to evaluate the comparative resistance profile of Rhipicephalus microplus isolates collected from seven districts of Uttar Pradesh, a northern state of India. Comparative analysis of the dose-response data using adult immersion test (AIT) against coumaphos, malathion, deltamethrin, ivermectin, and fipronil revealed that all the isolates were resistant to discriminating concentration of deltamethrin having LC50 of 295.12-436.52 ppm with a resistance ratio of 22.02-32.58. An emerging low level of ivermectin resistance (resistance ratio, RR50 = 1.03-2.26) with LC50 in the range of 22.39-48.98 ppm was found across the isolates. The coumaphos was highly effective against all except Amethi (AMT) isolate. Similarly, malathion was efficacious against most of the isolates except Pratapgarh (PRT) and Sultanpur (SUL) isolates showing LC50 of 5128.61 and 5623.41 ppm, respectively. All the isolates were responsive to fipronil. Comparative detoxifying enzymes profiles revealed a significant correlation between the increased activity of esterase and deltamethrin resistance. The GST activity was 51.2% correlated with RR50 of malathion while esterase activity was significantly correlated (68.9%) with RR50 of coumaphos. No correlation between the ivermectin resistance and enzyme activity was established. Multiple sequence analysis of S4-5 linker region of the sodium channel gene of all the isolates revealed a point mutation at 190th position (C190A) which is associated with deltamethrin resistance. The possible tick management strategies in this part of the country are discussed.
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12
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Santos EGGD, Bezerra WADS, Temeyer KB, León AAPD, Costa-Junior LM, Soares AMDS. Effects of essential oils on native and recombinant acetylcholinesterases of Rhipicephalus microplus. ACTA ACUST UNITED AC 2021; 30:e002221. [PMID: 34076049 DOI: 10.1590/s1984-29612021024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Accepted: 02/18/2021] [Indexed: 08/09/2024]
Abstract
This study reports the action of essential oils (EO) from five plants on the activity of native and recombinant acetylcholinesterases (AChE) from Rhipicephalus microplus. Enzyme activity of native susceptible AChE extract (S.AChE), native resistant AChE extract (R.AChE), and recombinant enzyme (rBmAChE1) was determined. An acetylcholinesterase inhibition test was used to verify the effect of the EO on enzyme activity. EO from Eucalyptus globulus, Citrus aurantifolia, Citrus aurantium var.dulcis inhibited the activity of S.AChE and R.AChE. Oils from the two Citrus species inhibited S.AChE and R.AChE in a similar way while showing greater inhibition on R.AChE. The oil from E. globulus inhibited native AChE, but no difference was observed between the S.AChE and R.AChE; however, 71% inhibition for the rBmAChE1 was recorded. Mentha piperita oil also inhibited S.AChE and R.AChE, but there was significant inhibition at the highest concentration tested. Cymbopogon winterianus oil did not inhibit AChE. Further studies are warranted with the oils from the two Citrus species that inhibited R.AChE because of the problem with R. microplus resistant to organophosphates, which target AChE. C. winterianus oil can be used against R. microplus populations that are resistant to organophosphates because its acaricidal properties act by mechanism(s) other than AChE inhibition.
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Affiliation(s)
| | | | - Kevin B Temeyer
- USDA-ARS Knipling-Bushland U.S. Livestock Insects Research Laboratory and Veterinary Pest Genomics Center, Kerrville, TX, United States of America
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13
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Yang P, Jia M, Zhu L. Acaricidal activity of the essential oil from Senecio cannabifolius and its constituents eucalyptol and camphor on engorged females and larvae of Rhipicephalus microplus (Acari: Ixodidae). EXPERIMENTAL & APPLIED ACAROLOGY 2021; 83:411-426. [PMID: 33590356 DOI: 10.1007/s10493-021-00590-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 01/19/2021] [Indexed: 06/12/2023]
Abstract
The objective of this experiment was to evaluate the acaricidal activity of Senecio cannabifolius essential oil, and two of its constituents, eucalyptol and camphor. Efficacy against females and larvae of Rhipicephalus (Boophilus) microplus was assessed by the adult immersion test (AIT) and the larval immersion test (LIT). The oil was analyzed by gas chromatography-flame ionization detection (GC-FID) and GC-mass spectrometry (MS) and in total 68 components were identified representing 99.2% of the essential oil. AIT revealed that the oil, eucalyptol, and camphor at the highest concentration presented efficacy of 68.9, 57.1, and 71.9%, respectively. LIT revealed that the essential oil and camphor achieved 100% mortality at concentration of 1.6% wt/vol, whereas eucalyptol showed moderate inhibitory activity. Biochemical assays indicated that the essential oil and camphor can reduce significantly overall detoxification enzyme activities in engorged females and larvae at high concentration (≥ 0.4% wt/vol), whereas the inhibitory effect of eucalyptol is weaker than that of the oil and camphor. Taken together our results indicated that the S. cannabifolius essential oil and its isolated constituent had potential for the development of a new and safe acaricide for the control of R. microplus ticks.
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Affiliation(s)
- Peipei Yang
- School of Food Science and Engineering, South China University of Technology, Wushan Road 381, Guangzhou, 510641, Guangdong Province, China
| | - Mengmeng Jia
- School of Food Science and Engineering, South China University of Technology, Wushan Road 381, Guangzhou, 510641, Guangdong Province, China
| | - Liang Zhu
- School of Food Science and Engineering, South China University of Technology, Wushan Road 381, Guangzhou, 510641, Guangdong Province, China.
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Cerqueira APM, Santana IB, Araújo JSC, Lima HG, Batatinha MJM, Branco A, Santos Junior MCD, Botura MB. Homology modeling, docking, molecular dynamics and in vitro studies to identify Rhipicephalus microplus acetylcholinesterase inhibitors. J Biomol Struct Dyn 2021; 40:6787-6797. [PMID: 33645442 DOI: 10.1080/07391102.2021.1889666] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Rhipicephalus microplus is an important ectoparasite of cattle, causing considerable economical losses. Resistance to chemical acaricides has stimulated the search for new antiparasitic drugs, including natural products as an eco-friendly alternative of control. Flavonoids represent a class of natural compounds with many biological activities, such as enzyme inhibitors. Acetylcholinesterase is an essential enzyme for tick survival that stands out as an important target for the development of acaricides. This work aimed to predict this 3D structure by homology modeling and use the model to identify compound with inhibitory activity. The model of R. microplus AChE1 (RmAChE1) was constructed using MODELLER program. The optimization and molecular dynamic investigation were performed in GROMACS program. The model developed was used, by molecular docking, to evaluate the anticholinesterase activity of flavonoids (quercetin, rutin, diosmin, naringin and hesperidin) and an acaricide synthetic (eserine). Additionally, in vitro inhibition of AChE and larval immersion tests were performed. The model of RmAChE1 showed to be sterically and energetically acceptable. In molecular dynamics simulations, the 3D structure remains stable with Root Mean Square Deviation = 3.58 Å and Root Mean Square Fluctuation = 1.43 Å. In molecular docking analyses, only eserine and quercetin show affinity energy to the RmAChE (Gridscore: -52.17 and -39.44 kcal/mol, respectively). Among the flavonoids, quercetin exhibited the best in vitro inhibition of AChE activity (15.8%) and mortality of larvae tick (30.2%). The use of in silico and in vitro techniques has shown that quercetin showed promising anti-tick activity and structural requirements to interact with RmAChE1. Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Amanda Ponce Morais Cerqueira
- Departamento de Biologia, Programa de Pós-Graduação em Biotecnologia, Universidade Estadual de Feira de Santana, Feira de Santana, BA, Brazil
| | - Isis Bugia Santana
- Departamento de Biologia, Programa de Pós-Graduação em Biotecnologia, Universidade Estadual de Feira de Santana, Feira de Santana, BA, Brazil
| | - Janay Stefany Carneiro Araújo
- Departamento de Biologia, Programa de Pós-Graduação em Biotecnologia, Universidade Estadual de Feira de Santana, Feira de Santana, BA, Brazil
| | - Hélimar Gonçalves Lima
- Laboratório de Toxicologia, Hospital de Medicina Veterinária, Universidade Federal da Bahia, Ondina, Salvador, BA, Brazil
| | - Maria José Moreira Batatinha
- Laboratório de Toxicologia, Hospital de Medicina Veterinária, Universidade Federal da Bahia, Ondina, Salvador, BA, Brazil
| | - Alexsandro Branco
- Departamento de Saúde, Universidade Estadual de Feira de Santana, Feira de Santana, BA, Brazil
| | | | - Mariana Borges Botura
- Departamento de Saúde, Universidade Estadual de Feira de Santana, Feira de Santana, BA, Brazil
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15
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In vitro and in silico studies of the larvicidal and anticholinesterase activities of berberine and piperine alkaloids on Rhipicephalus microplus. Ticks Tick Borne Dis 2020; 12:101643. [PMID: 33388555 DOI: 10.1016/j.ttbdis.2020.101643] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 12/22/2020] [Accepted: 12/23/2020] [Indexed: 12/20/2022]
Abstract
Rhipicephalus microplus is responsible for high economic losses in livestock and its control has become difficult due to the establishment of tick populations resistant to commercial acaricides. This study aimed to evaluate the in vitro larvicidal effect of the alkaloids berberine and piperine, and also to investigate their inhibitory mechanisms against the acetylcholinesterase enzyme. The effects of the alkaloids on larvae were observed through the immersion test at the following concentrations: 1.5; 3; 6; 12; 16 and 24 mM. Berberine and piperine presented larvicidal activity greater than 95 %, not differing from 100 % for the positive fipronil control (p > 0.05). Of the two alkaloids, piperine had a lower effective concentration (EC), with an EC50 of 6.04 mM. The acetylcholinesterase enzyme used in the study was obtained from R. microplus larvae (RmAChE) and the anticholinesterase activity was determined spectrophotometrically. The highest anticholinesterase activity, measured as inhibition concentration (IC), was observed for berberine (IC50 = 88.13 μM), while piperine showed lower activity (IC50 > 200 μM). Docking studies in RmAChE, followed by 10 ns molecular dynamics simulation, suggest that berberine stabilizes the RmAChE at lower Root-Mean-Square Deviation (RMSD) than Apo protein. Few hydrogen-bond interactions between berberine and RmAChE residues were balanced by hydrophobic and π-type interactions. Berberine fills preferentially the peripheral anionic site (PAS), which correlates with its non-competitive mechanism. These results suggest that berberine and piperine alkaloids have an in vitro acaricidal action on R. microplus larvae, and the likely mechanism of action of berberine is related to RmAChE inhibition when accessing the PAS residues. These findings could help the study of new natural products that could inhibit RmAChE and aid in the development of new acaricides.
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16
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Temeyer KB, Schlechte KG, Olafson PU, Drolet BS, Tidwell JP, Osbrink WLA, Showler AT, Gross AD, Pérez de León AA. Association of Salivary Cholinesterase With Arthropod Vectors of Disease. JOURNAL OF MEDICAL ENTOMOLOGY 2020; 57:1679-1685. [PMID: 32459332 DOI: 10.1093/jme/tjaa096] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Indexed: 06/11/2023]
Abstract
Acetylcholinesterase (AChE) was previously reported to be present in saliva of the southern cattle tick, Rhipicephalus (Boophilus) microplus (Canestrini), with proposed potential functions to 1) reduce acetylcholine toxicity during rapid engorgement, 2) modulate host immune responses, and 3) to influence pathogen transmission and establishment in the host. Potential modulation of host immune responses might include participation in salivary-assisted transmission and establishment of pathogens in the host as has been reported for a number of arthropod vector-borne diseases. If the hypothesis that tick salivary AChE may alter host immune responses is correct, we reasoned that similar cholinesterase activities might be present in saliva of additional arthropod vectors. Here, we report the presence of AChE-like activity in the saliva of southern cattle ticks, Rhipicephalus (Boophilus) microplus; the lone star tick, Amblyomma americanum (Linnaeus); Asian tiger mosquitoes, Aedes albopictus (Skuse); sand flies, Phlebotomus papatasi (Scopoli); and biting midges, Culicoides sonorensis Wirth and Jones. Salivary AChE-like activity was not detected for horn flies Haematobia irritans (L.), stable flies Stomoxys calcitrans (L.), and house flies Musca domestica L. Salivary cholinesterase (ChE) activities of arthropod vectors of disease-causing agents exhibited various Michaelis-Menten KM values that were each lower than the KM value of bovine serum AChE. A lower KM value is indicative of higher affinity for substrate and is consistent with a hypothesized role in localized depletion of host tissue acetylcholine potentially modulating host immune responses at the arthropod bite site that may favor ectoparasite blood-feeding and alter host defensive responses against pathogen transmission and establishment.
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Affiliation(s)
- Kevin B Temeyer
- Knipling-Bushland U.S. Livestock Insects Research Laboratory, USDA-ARS, Kerrville, TX
| | - Kristie G Schlechte
- Knipling-Bushland U.S. Livestock Insects Research Laboratory, USDA-ARS, Kerrville, TX
| | - Pia U Olafson
- Knipling-Bushland U.S. Livestock Insects Research Laboratory, USDA-ARS, Kerrville, TX
| | - Barbara S Drolet
- Arthropod-Borne Animal Diseases Research Unit, Center for Grain and Animal Health Research, USDA-ARS, Manhattan, KS
| | - Jason P Tidwell
- Cattle Fever Tick Research Laboratory, USDA-ARS, Edinburg, TX
| | - Weste L A Osbrink
- Knipling-Bushland U.S. Livestock Insects Research Laboratory, USDA-ARS, Kerrville, TX
| | - Allan T Showler
- Knipling-Bushland U.S. Livestock Insects Research Laboratory, USDA-ARS, Kerrville, TX
| | - Aaron D Gross
- Molecular Physiology and Toxicology Laboratory, Department of Entomology, Virginia Polytechnic Institute and State University, Blacksburg, VA
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17
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Cardoso ADS, Santos EGG, Lima ADS, Temeyer KB, Pérez de León AA, Costa LM, Soares AMDS. Terpenes on Rhipicephalus (Boophilus) microplus: Acaricidal activity and acetylcholinesterase inhibition. Vet Parasitol 2020; 280:109090. [PMID: 32208306 DOI: 10.1016/j.vetpar.2020.109090] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 03/16/2020] [Accepted: 03/17/2020] [Indexed: 10/24/2022]
Abstract
The Rhipicephalus (Boophilus) microplus tick is the main ectoparasite of cattle in tropical and subtropical regions worldwide. Resistance to chemical acaricides has become widespread affirming the need for new drugs to tick control. Terpenes have become a promising alternative for cattle tick control, however the mechanism of action of these compounds is still controversial. Inhibition of acetylcholinesterase (AChE) is a well established mechanism of action of organophosphate and carbamate acaricides, but the possible action of terpenes on tick AChEs has seldom been studied in resistant and sensitive strains of R. (B.) microplus. The aim of the present study was to evaluate terpene inhibition of AChE from resistant and sensitive strains of R. (B.) microplus in correlation with their acaricidal activity. Among the terpenes used in the present study, p-cymene, thymol, carvacrol, and citral displayed acaricidal activity with LC50 of 1.75, 1.54, 1.41, and 0.38 mg.mL-1 for the susceptible strain, and LC50 of 1.40, 1.81, 1.10, and 1.13 mg.mL-1 for the resistant strain. Thymol and carvacrol inhibited the AChE of the susceptible strain larvae with IC50 of 0.93 and 0.04 mg.mL-1, respectively. The IC50 exhibited by eucalyptol, carvacrol and thymol for AChE of the resistant strain larvae were 0.36, 0.28, and 0.13 mg.mL-1, respectively. This was the first study to investigate the action of terpenes on AChE from susceptible and resistant R. (B.) microplus. As not all terpenes with acaridical activity showed AChE inhibition, the participation of AChE in the acaricidal activity of terpenes needs further investigation.
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Affiliation(s)
| | | | | | - Kevin B Temeyer
- Knipling-Bushland U.S.Livestock Insects Research Laboratory, Kerrville, TX, United States
| | | | - Livio Martins Costa
- Laboratory of Parasite Control, Federal University of Maranhão, Sao Luís, MA, Brazil.
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18
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Fular A, Gupta S, Sharma AK, Kumar S, Upadhaya D, Shakya M, Nagar G, Ghosh S. Standardization of tick specific biochemical tools for estimation of esterases, monooxygenases and glutathione S-transferase for characterization of acaricide resistance. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2020; 164:130-139. [PMID: 32284118 DOI: 10.1016/j.pestbp.2020.01.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 12/27/2019] [Accepted: 01/17/2020] [Indexed: 06/11/2023]
Abstract
Protocols to determine metabolic resistance in ticks were mainly derived from reports published using mosquitoes and agriculturally important insects without prior standardization. In the present study, biochemical assays were standardized to quantify acaricide metabolizing enzymes in tick homogenates. Three variables viz., age, number of larvae and reaction time were optimized using reference susceptible IVRI-I and deltamethrin resistant IVRI-IV (Resistance Factor = 194) tick strains. The optimum conditions for estimation of general esterases were 10-15 day old 40 larvae with 15 mins reaction time, 15-20 day old 40 larvae with 20 mins reaction time for Glutathione S- transferase, while 10-15 day old 80 larvae with 5 mins reaction time for monooxygenase. The standardized protocols were further validated in multi acaricide resistant strain (IVRI-V) and in nine field isolates having variable resistant factors to different acaricides. In all the nine heterogeneous field isolates, a significant correlation (p < .05) between resistance to synthetic pyrethroids and over-expression of esterases and monooxygenase was noticed. Similarly, esterases and GST activities were significantly correlated with resistance to organophosphates. The details of the assay protocol are explained for adoption in different laboratories.
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Affiliation(s)
- Ashutosh Fular
- Entomology Laboratory, Division of Parasitology, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly 243122, U.P., India
| | - Snehil Gupta
- Entomology Laboratory, Division of Parasitology, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly 243122, U.P., India
| | - Anil Kumar Sharma
- Entomology Laboratory, Division of Parasitology, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly 243122, U.P., India
| | - Sachin Kumar
- Entomology Laboratory, Division of Parasitology, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly 243122, U.P., India
| | - Deepak Upadhaya
- Entomology Laboratory, Division of Parasitology, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly 243122, U.P., India
| | - Mukesh Shakya
- Entomology Laboratory, Division of Parasitology, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly 243122, U.P., India
| | - Gaurav Nagar
- Entomology Laboratory, Division of Parasitology, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly 243122, U.P., India
| | - Srikant Ghosh
- Entomology Laboratory, Division of Parasitology, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly 243122, U.P., India.
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Lima HGD, Santos FO, Santos ACV, Silva GDD, Santos RJD, Carneiro KDO, Reis IMA, Estrela IDO, Freitas HFD, Bahiense TC, Pita SSDR, Uzeda RS, Branco A, Costa SL, Batatinha MJM, Botura MB. Anti-tick effect and cholinesterase inhibition caused by Prosopis juliflora alkaloids: in vitro and in silico studies. REVISTA BRASILEIRA DE PARASITOLOGIA VETERINARIA 2020; 29:e019819. [DOI: 10.1590/s1984-29612020036] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Accepted: 04/30/2020] [Indexed: 01/23/2023]
Abstract
Abstract We investigated the in vitro acaricide activity of the methanolic extract (ME) and alkaloid-rich fraction (AF) of Prosopis juliflora on Rhipicephalus microplus and correlated this effect with acetylcholinesterase (AChE) inhibition. The acaricide activity was evaluated using adult and larval immersion tests. Also, we studied the possible interaction mechanism of the major alkaloids present in this fraction via molecular docking at the active site of R. microplus AChE1 (RmAChE1). Higher reproductive inhibitory activity of the AF was recorded, with effective concentration (EC50) four times lower than that of the ME (31.6 versus 121 mg/mL). The AF caused mortality of tick larvae, with lethal concentration 50% (LC50) of 13.8 mg/mL. Both ME and AF were seen to have anticholinesterase activity on AChE of R. microplus larvae, while AF was more active with half-maximal inhibitory concentration (IC50) of 0.041 mg/mL. The LC-MS/MS analyses on the AF led to identification of three alkaloids: prosopine (1), juliprosinine (2) and juliprosopine (3). The molecular docking studies revealed that these alkaloids had interactions at the active site of the RmAChE1, mainly relating to hydrogen bonds and cation-pi interactions. We concluded that the alkaloids of P. juliflora showed acaricide activity on R. microplus and acted through an anticholinesterase mechanism.
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20
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Temeyer KB, Schlechte KG, McDonough WP. Baculoviral Expression of Presumptive OP-Resistance Mutations in BmAChE1 of Rhipicephalus (Boophilus) microplus (Ixodida: Ixodidae) and Biochemical Resistance to OP Inhibition. JOURNAL OF MEDICAL ENTOMOLOGY 2019; 56:1318-1323. [PMID: 31102447 DOI: 10.1093/jme/tjz062] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Indexed: 06/09/2023]
Abstract
The southern cattle tick, Rhipicephalus (Boophilus) microplus (Canestrini), transmits bovine babesiosis and anaplasmosis, and is endemic to Mexico, Latin and South America. Rhipicephalus (B.) microplus infestations within the United States are a continuing threat to U.S. cattle producers. An importation barrier between Texas and Mexico keeps the ticks from re-entering the United States. All cattle imported into the United States are dipped in an organophosphate (OP) acaricide and hand inspected for presence of ticks. Tick resistance has developed to most available acaricides, including coumaphos, the OP used in the cattle dip vats. OP-resistance can result from one or more mutations in the gene encoding the enzyme, acetylcholinesterase (AChE), resulting in production of an altered AChE resistant to OP inhibition. Previous research reported a large number of BmAChE1 mutations associated with OP resistance. We report baculovirus expression of recombinant tick BmAChE1 (rBmAChE) enzymes containing a single resistance-associated mutation, to assess their contribution to OP inhibition resistance. Surprisingly, of the naturally occurring BmAChE1 resistance-associated mutations, only D188G resulted in markedly reduced sensitivity to OP-inhibition suggesting that OP-insensitivity in BmAChE1 may result from the D188G mutation, or may possibly result from multiple mutations, each contributing a small decrease in OP sensitivity. Furthermore, an OP-insensitivity mutation (G119S) found in mosquitoes was expressed in rBmAChE1, resulting in 500-2000-fold decreased sensitivity to OP inhibition. Recombinant BmAChE1 with the G119S mutation demonstrated the lack of any structural prohibition to broad and high-level OP-insensitivity, suggesting potential increases in tick OP-resistance that would threaten the U.S. importation barrier to ticks.
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Affiliation(s)
- Kevin B Temeyer
- Knipling-Bushland U.S. Livestock Insects Research Laboratory, U.S. Department of Agriculture - Agricultural Research Service, Kerrville, Texas
| | - Kristie G Schlechte
- Knipling-Bushland U.S. Livestock Insects Research Laboratory, U.S. Department of Agriculture - Agricultural Research Service, Kerrville, Texas
| | - William P McDonough
- Knipling-Bushland U.S. Livestock Insects Research Laboratory, U.S. Department of Agriculture - Agricultural Research Service, Kerrville, Texas
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Kumar R. Molecular markers and their application in the monitoring of acaricide resistance in Rhipicephalus microplus. EXPERIMENTAL & APPLIED ACAROLOGY 2019; 78:149-172. [PMID: 31190248 DOI: 10.1007/s10493-019-00394-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Accepted: 06/03/2019] [Indexed: 06/09/2023]
Abstract
Monitoring acaricide resistance and understanding the underlying mechanisms are critically important in developing strategies for resistance management and tick control. Identification of single nucleotide polymorphisms in the acaricide-resistant associated gene of Rhipicephalus microplus has enabled the development of molecular markers for detection and monitoring of resistance against different types of acaricide. There are many molecular markers developed for resistance monitoring, including mutations on target genes such as sodium channel, acetylcholinesterase, carboxylesterase, β-adrenergic octopamine receptor, octopamine-tyramine etc. Molecular genotyping through molecular markers can detect the presence of resistance-associated genes in a tick population before it reaches high frequency. This review aims to provide an update on the various molecular markers discovered to date from different regions of the world.
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Affiliation(s)
- Rinesh Kumar
- College of Veterinary Science and Animal Husbandry, Rewa, Madhya Pradesh, India.
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Fular A, Sharma AK, Kumar S, Nagar G, Chigure G, Ray D, Ghosh S. Establishment of a multi-acaricide resistant reference tick strain (IVRI-V) of Rhipicephalus microplus. Ticks Tick Borne Dis 2018; 9:1184-1191. [DOI: 10.1016/j.ttbdis.2018.04.014] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Revised: 04/18/2018] [Accepted: 04/21/2018] [Indexed: 10/17/2022]
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Rodriguez-Vivas RI, Jonsson NN, Bhushan C. Strategies for the control of Rhipicephalus microplus ticks in a world of conventional acaricide and macrocyclic lactone resistance. Parasitol Res 2018; 117:3-29. [PMID: 29152691 PMCID: PMC5748392 DOI: 10.1007/s00436-017-5677-6] [Citation(s) in RCA: 153] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Accepted: 11/06/2017] [Indexed: 12/11/2022]
Abstract
Infestations with the cattle tick, Rhipicephalus microplus, constitute the most important ectoparasite problem for cattle production in tropical and subtropical regions worldwide, resulting in major economic losses. The control of R. microplus is mostly based on the use of conventional acaricides and macrocyclic lactones. However, the intensive use of such compounds has resulted in tick populations that exhibit resistance to all major acaricide chemical classes. Consequently, there is a need for the development of alternative approaches, possibly including the use of animal husbandry practices, synergized pesticides, rotation of acaricides, pesticide mixture formulations, manual removal of ticks, selection for host resistance, nutritional management, release of sterile male hybrids, environmental management, plant species that are unfavourable to ticks, pasture management, plant extracts, essential oils and vaccination. Integrated tick management consists of the systematic combination of at least two control technologies aiming to reduce selection pressure in favour of acaricide-resistant individuals, while maintaining adequate levels of animal production. The purpose of this paper is to present a current review on conventional acaricide and macrocyclic lactone resistance for better understanding and control of resistant ticks with particular emphasis on R. microplus on cattle.
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Affiliation(s)
- Roger I Rodriguez-Vivas
- Facultad de Medicina Veterinaria y Zootecnia, Campus de Ciencias Biológicas y Agropecuarias, Universidad Autónoma de Yucatán, km. 15.5 Carretera Mérida-Xmatkuil, 97000, Mérida, Yucatán, Mexico.
| | - Nicholas N Jonsson
- College of Medical, Veterinary and Life Sciences, University of Glasgow, G61 1QH, Glasgow, UK
| | - Chandra Bhushan
- Bayer Animal Health GmbH, Kaiser-Wilhelm-Alee 10, 51368, Leverkusen, Germany
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Brito LG, de Oliveira Nery L, da Silva Barbieri F, Huacca MEF, dos Santos Pereira S, da Silva RR, de Freitas Fernanades CC, de Sena Oliveira MC. Molecular quantitative assay for esterase-mediated organophosphate resistance in Rhipicephalus microplus. Ticks Tick Borne Dis 2017; 8:725-732. [DOI: 10.1016/j.ttbdis.2017.05.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Revised: 05/10/2017] [Accepted: 05/13/2017] [Indexed: 02/04/2023]
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Meng X, Xu X, Bao H, Wang J, Liu Z. Characterization of the Fifth Putative Acetylcholinesterase in the Wolf Spider, Pardosa pseudoannulata. Molecules 2017; 22:E1118. [PMID: 28696352 PMCID: PMC6152279 DOI: 10.3390/molecules22071118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Revised: 06/29/2017] [Accepted: 07/01/2017] [Indexed: 11/17/2022] Open
Abstract
Background: Acetylcholinesterase (AChE) is an important neurotransmitter hydrolase in invertebrate and vertebrate nervous systems. The number of AChEs is various among invertebrate species, with different functions including the 'classical' role in terminating synaptic transmission and other 'non-classical' roles. Methods: Using rapid amplification of cDNA ends (RACE) technology, a new putative AChE-encoding gene was cloned from Pardosa pseudoannulata, an important predatory natural enemy. Sequence analysis and in vitro expression were employed to determine the structural features and biochemical properties of this putative AChE. Results: The cloned AChE contained the most conserved motifs of AChEs family and was clearly clustered with Arachnida AChEs. Determination of biochemical properties revealed that the recombinant enzyme had the obvious preference for the substrate ATC (acetylthiocholine iodide) versus BTC (butyrylthiocholine iodide). The AChE was highly sensitive to AChE-specific inhibitor BW284C51, but not butyrylcholinesterase-specific inhibitor tetraisopropyl pyrophosphoramide (ISO-OMPA). Based on these results, we concluded that a new AChE was identified from P. pseudoannulata and denoted as PpAChE5. Conclusion: Here we report the identification of a new AChE from P. pseudoannulata and increased the AChE number to five in this species. Although PpAChE5 had the biggest Vmax value among five identified AChEs, it showed relatively low affinity with ATC. Similar sensitivity to test insecticides indicated that this AChE might serve as the target for both organophosphorus and carbamate insecticides.
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Affiliation(s)
- Xiangkun Meng
- Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), College of Plant Protection, Nanjing Agricultural University, Weigang 1, Nanjing 210095, China.
- College of Horticulture and Plant Protection, Yangzhou University, Yangzhou 225009, China.
| | - Xixia Xu
- Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), College of Plant Protection, Nanjing Agricultural University, Weigang 1, Nanjing 210095, China.
| | - Haibo Bao
- Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), College of Plant Protection, Nanjing Agricultural University, Weigang 1, Nanjing 210095, China.
| | - Jianjun Wang
- College of Horticulture and Plant Protection, Yangzhou University, Yangzhou 225009, China.
| | - Zewen Liu
- Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), College of Plant Protection, Nanjing Agricultural University, Weigang 1, Nanjing 210095, China.
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Chatonnet A, Lenfant N, Marchot P, Selkirk ME. Natural genomic amplification of cholinesterase genes in animals. J Neurochem 2017; 142 Suppl 2:73-81. [PMID: 28382676 DOI: 10.1111/jnc.13990] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Revised: 02/07/2017] [Accepted: 02/09/2017] [Indexed: 12/31/2022]
Abstract
Tight control of the concentration of acetylcholine at cholinergic synapses requires precise regulation of the number and state of the acetylcholine receptors, and of the synthesis and degradation of the neurotransmitter. In particular, the cholinesterase activity has to be controlled exquisitely. In the genome of the first experimental models used (man, mouse, zebrafish and drosophila), there are only one or two genes coding for cholinesterases, whereas there are more genes for their closest relatives the carboxylesterases. Natural amplification of cholinesterase genes was first found to occur in some cancer cells and in insect species subjected to evolutionary pressure by insecticides. Analysis of the complete genome sequences of numerous representatives of the various metazoan phyla show that moderate amplification of cholinesterase genes is not uncommon in molluscs, echinoderms, hemichordates, prochordates or lepidosauria. Amplification of acetylcholinesterase genes is also a feature of parasitic nematodes or ticks. In these parasites, over-production of cholinesterase-like proteins in secreted products and the saliva are presumed to have effector roles related to host infection. These amplification events raise questions about the role of the amplified gene products, and the adaptation processes necessary to preserve efficient cholinergic transmission. This is an article for the special issue XVth International Symposium on Cholinergic Mechanisms.
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Affiliation(s)
- Arnaud Chatonnet
- Dynamique Musculaire et Métabolisme, INRA, Université Montpellier, Place Viala, Montpellier France
| | - Nicolas Lenfant
- Dynamique Musculaire et Métabolisme, INRA, Université Montpellier, Place Viala, Montpellier France.,Aix-Marseille Université / Centre National de la Recherche Scientifique, Architecture et Fonction des Macromolécules Biologiques laboratory, Marseille, France
| | - Pascale Marchot
- Aix-Marseille Université / Centre National de la Recherche Scientifique, Architecture et Fonction des Macromolécules Biologiques laboratory, Marseille, France
| | - Murray E Selkirk
- Department of Life Sciences, Imperial College London, London, UK
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Meng X, Li C, Xiu C, Zhang J, Li J, Huang L, Zhang Y, Liu Z. Identification and Biochemical Properties of Two New Acetylcholinesterases in the Pond Wolf Spider (Pardosa pseudoannulata). PLoS One 2016; 11:e0158011. [PMID: 27337188 PMCID: PMC4919072 DOI: 10.1371/journal.pone.0158011] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Accepted: 06/08/2016] [Indexed: 01/17/2023] Open
Abstract
Acetylcholinesterase (AChE), an important neurotransmitter hydrolase in both invertebrates and vertebrates, is targeted by organophosphorus and carbamate insecticides. In this study, two new AChEs were identified in the pond wolf spider Pardosa pseudoannulata, an important predatory natural enemy of several insect pests. In total, four AChEs were found in P. pseudoannulata (including two AChEs previously identified in our laboratory). The new putative AChEs PpAChE3 and PpAChE4 contain most of the common features of the AChE family, including cysteine residues, choline binding sites, the conserved sequence 'FGESAG' and conserved aromatic residues but with a catalytic triad of 'SDH' rather than 'SEH'. Recombinant enzymes expressed in Sf9 cells showed significant differences in biochemical properties compared to other AChEs, such as the optimal pH, substrate specificity, and catalytic efficiency. Among three test substrates, PpAChE1, PpAChE3 and PpAChE4 showed the highest catalytic efficiency (Vmax/KM) for ATC (acetylthiocholine iodide), with PpAChE3 exhibiting a clear preference for ATC based on the VmaxATC/VmaxBTC ratio. In addition, the four PpAChEs were more sensitive to the AChE-specific inhibitor BW284C51, which acts against ATC hydrolysis, than to the BChE-specific inhibitor ISO-OMPA, which acts against BTC hydrolysis, with at least a 8.5-fold difference in IC50 values for each PpAChE. PpAChE3, PpAChE4, and PpAChE1 were more sensitive than PpAChE2 to the tested Carb insecticides, and PpAChE3 was more sensitive than the other three AChEs to the tested OP insecticides. Based on all the results, two new functional AChEs were identified from P. pseudoannulata. The differences in AChE sequence between this spider and insects enrich our knowledge of invertebrate AChE diversity, and our findings will be helpful for understanding the selectivity of insecticides between insects and natural enemy spiders.
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Affiliation(s)
- Xiangkun Meng
- Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), College of Plant Protection, Nanjing Agricultural University, Weigang 1, Nanjing, 210095, China
| | - Chunrui Li
- Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), College of Plant Protection, Nanjing Agricultural University, Weigang 1, Nanjing, 210095, China
| | - Chunli Xiu
- Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), College of Plant Protection, Nanjing Agricultural University, Weigang 1, Nanjing, 210095, China
| | - Jianhua Zhang
- Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), College of Plant Protection, Nanjing Agricultural University, Weigang 1, Nanjing, 210095, China
| | - Jingjing Li
- Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), College of Plant Protection, Nanjing Agricultural University, Weigang 1, Nanjing, 210095, China
| | - Lixin Huang
- Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), College of Plant Protection, Nanjing Agricultural University, Weigang 1, Nanjing, 210095, China
| | - Yixi Zhang
- Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), College of Plant Protection, Nanjing Agricultural University, Weigang 1, Nanjing, 210095, China
- * E-mail: (ZWL); (YXZ)
| | - Zewen Liu
- Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), College of Plant Protection, Nanjing Agricultural University, Weigang 1, Nanjing, 210095, China
- * E-mail: (ZWL); (YXZ)
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28
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Temeyer KB, Tuckow AP. Tick Salivary Cholinesterase: A Probable Immunomodulator of Host-parasite Interactions. JOURNAL OF MEDICAL ENTOMOLOGY 2016; 53:500-504. [PMID: 26794231 DOI: 10.1093/jme/tjv252] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Accepted: 12/23/2015] [Indexed: 06/05/2023]
Abstract
The southern cattle tick, Rhipicephalus (Boophilus) microplus (Canestrini), is the most economically important cattle ectoparasite in the world. Rhipicephalus microplus and Rhipicephalus annulatus (Say) continue to threaten U.S. cattle producers despite eradication and an importation barrier based on inspection, dipping of imported cattle in organophosphate (OP) acaricide, and quarantine of infested premises. OP acaricides inhibit acetylcholinesterase (AChE), essential to tick central nervous system function. Unlike vertebrates, ticks possess at least three genes encoding AChEs, differing in amino acid sequence and biochemical properties. Genomic analyses of R. microplus and the related tick, Ixodes scapularis, suggest that ticks contain many genes encoding different AChEs. This work is the first report of a salivary cholinesterase (ChE) activity in R. microplus, and discusses complexity of the cholinergic system in ticks and significance of tick salivary ChE at the tick-host interface. It further provides three hypotheses that the salivary ChE plausibly functions 1) to reduce presence of potentially toxic acetylcholine present in the large bloodmeal imbibed during rapid engorgement, 2) to modulate the immune response (innate and/or acquired) of the host to tick antigens, and 3) to influence transmission and establishment of pathogens within the host animal. Ticks are vectors for a greater number and variety of pathogens than any other parasite, and are second only to mosquitoes (owing to malaria) as vectors of serious human disease. Saliva-assisted transmission (SAT) of pathogens is well-known; however, the salivary components participating in the SAT process remain to be elucidated.
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Affiliation(s)
- Kevin B Temeyer
- Knipling-Bushland U.S. Livestock Insects Research Laboratory, U.S. Department of Agriculture-Agricultural Research Service, 2700 Fredericksburg Road, Kerrville, Texas 78028 (; ) and
| | - Alexander P Tuckow
- Knipling-Bushland U.S. Livestock Insects Research Laboratory, U.S. Department of Agriculture-Agricultural Research Service, 2700 Fredericksburg Road, Kerrville, Texas 78028 (; ) and
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Tuckow AP, Temeyer KB. Discovery, adaptation and transcriptional activity of two tick promoters: Construction of a dual luciferase reporter system for optimization of RNA interference in rhipicephalus (boophilus) microplus cell lines. INSECT MOLECULAR BIOLOGY 2015; 24:454-466. [PMID: 25892533 DOI: 10.1111/imb.12172] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Revised: 02/10/2015] [Accepted: 03/06/2015] [Indexed: 06/04/2023]
Abstract
Dual luciferase reporter systems are valuable tools for functional genomic studies, but have not previously been developed for use in tick cell culture. We evaluated expression of available luciferase constructs in tick cell cultures derived from Rhipicephalus (Boophilus) microplus, an important vector of bovine babesiosis and anaplasmosis. Commercial promoters were evaluated for transcriptional activity driving luciferase expression in the tick cell lines. The human phosphoglycerate kinase (PGK) promoter resulted in detectable firefly luciferase activity within 2 days post-transfection of the R. microplus cell line BME26, with maximal activity at 5 days post-transfection. Several other promoters were weaker or inactive in the tick cells, prompting identification and assessment of transcriptional activity of the homologous ribosomal protein L4 (rpL4, GenBank accession no.: KM516205) and elongation factor 1α (EF-1α, GenBank accession no.: KM516204) promoters cloned from R. microplus. Evaluation of luciferase expression driven by various promoters in tick cell culture resulted in selection of the R. microplus rpL4 promoter and the human PGK promoter driving transcription of sequences encoding modified firefly and NanoLuc® luciferases for construction of a dual luciferase reporter system for use in tick cell culture.
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Affiliation(s)
- A P Tuckow
- USDA, Agricultural Research Service, Knipling-Bushland U.S. Livestock Insects Research Laboratory, Kerrville, TX, USA
| | - K B Temeyer
- USDA, Agricultural Research Service, Knipling-Bushland U.S. Livestock Insects Research Laboratory, Kerrville, TX, USA
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30
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Bendele KG, Guerrero FD, Miller RJ, Li AY, Barrero RA, Moolhuijzen PM, Black M, McCooke JK, Meyer J, Hill CA, Bellgard MI. Acetylcholinesterase 1 in populations of organophosphate-resistant North American strains of the cattle tick, Rhipicephalus microplus (Acari: Ixodidae). Parasitol Res 2015; 114:3027-40. [PMID: 25952704 DOI: 10.1007/s00436-015-4505-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Accepted: 04/28/2015] [Indexed: 10/23/2022]
Abstract
Rhipicephalus microplus, the cattle fever tick, is a global economic problem to the cattle industry due to direct infestation of cattle and pathogens transmitted during feeding. Cattle fever tick outbreaks continue to occur along the Mexico-US border even though the tick has been eradicated from the USA. The organophosphate (OP) coumaphos targets acetylcholinesterase (AChE) and is the approved acaricide for eradicating cattle fever tick outbreaks. There is evidence for coumaphos resistance developing in cattle ticks in Mexico, and OP-resistant R. microplus ticks were discovered in outbreak populations of Texas in 2005. The molecular basis of coumaphos resistance is not known, and our study was established to gather further information on whether AChE1 is involved in the resistance mechanism. We also sought information on allele diversity in tick populations with different levels of coumaphos resistance. The overarching project goal was to define OP resistance-associated gene mutations such that a DNA-based diagnostic assay could be developed to assist the management of resistance. Three different AChE transcripts have been reported in R. microplus, and supporting genomic and transcriptomic data are available at CattleTickBase. Here, we report the complete R. microplus AChE1 gene ascertained by sequencing a bacterial artificial chromosome clone containing the entire coding region and the flanking 5' and 3' regions. We also report AChE1 sequences of larval ticks from R. microplus strains having different sensitivities to OP. To accomplish this, we sequenced a 669-bp region of the AChE1 gene corresponding to a 223 amino acid region of exon 2 to assess alleles in seven strains of R. microplus with varying OP resistance phenotypes. We identified 72 AChE1 sequence variants, 2 of which are strongly associated with OP-resistant phenotypes. Esterase-like sequences from the R. microplus transcriptome RmiTr Version 1.0 were compared to the available sequence databases to identify other transcripts with similarity to AChE1.
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Affiliation(s)
- Kylie G Bendele
- USDA-ARS Knipling-Bushland U. S. Livestock Insects Research Laboratory, 2700 Fredericksburg Road, Kerrville, TX, 78028, USA,
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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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Swale DR, Tong F, Temeyer KB, Li A, Lam PCH, Totrov MM, Carlier PR, Pérez de León AA, Bloomquist JR. Inhibitor profile of bis(n)-tacrines and N-methylcarbamates on acetylcholinesterase from Rhipicephalus (Boophilus) microplus and Phlebotomus papatasi. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2013; 106:10.1016/j.pestbp.2013.03.005. [PMID: 24187393 PMCID: PMC3811934 DOI: 10.1016/j.pestbp.2013.03.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The cattle tick, Rhipicephalus (Boophilus) microplus (Bm), and the sand fly, Phlebotomus papatasi (Pp), are disease vectors to cattle and humans, respectively. The purpose of this study was to characterize the inhibitor profile of acetylcholinesterases from Bm (BmAChE1) and Pp (PpAChE) compared to human and bovine AChE, in order to identify divergent pharmacology that might lead to selective inhibitors. Results indicate that BmAChE has low sensitivity (IC50 = 200 μM) toward tacrine, a monovalent catalytic site inhibitor with sub micromolar blocking potency in all previous species tested. Similarly, a series of bis(n)-tacrine dimer series, bivalent inhibitors and peripheral site AChE inhibitors possess poor potency toward BmAChE. Molecular homology models suggest the rBmAChE enzyme possesses a W384F orthologous substitution near the catalytic site, where the larger tryptophan side chain obstructs the access of larger ligands to the active site, but functional analysis of this mutation suggests it only partially explains the low sensitivity to tacrine. In addition, BmAChE1 and PpAChE have low nanomolar sensitivity to some experimental carbamate anticholinesterases originally designed for control of the malaria mosquito, Anopheles gambiae. One experimental compound, 2-((2-ethylbutyl)thio)phenyl methylcarbamate, possesses >300-fold selectivity for BmAChE1 and PpAChE over human AChE, and a mouse oral LD50 of >1500 mg/kg, thus providing an excellent new lead for vector control.
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Affiliation(s)
- Daniel R. Swale
- Department of Entomology and Nematology, Emerging Pathogens Institute, University of Florida, Gainesville, FL, 32611, USA
| | - Fan Tong
- Department of Entomology and Nematology, Emerging Pathogens Institute, University of Florida, Gainesville, FL, 32611, USA
| | - Kevin B. Temeyer
- Knipling-Bushland U.S. Livestock Insects Research Laboratory, United States Department of Agricultural-Agricultural Research Service, 2700 Fredericksburg Road, Kerrville, TX, 78028, USA
| | - Andrew Li
- Knipling-Bushland U.S. Livestock Insects Research Laboratory, United States Department of Agricultural-Agricultural Research Service, 2700 Fredericksburg Road, Kerrville, TX, 78028, USA
| | - Polo C-H. Lam
- Molsoft LLC, 3366 North Torrey Pines Court, Suite 300, La Jolla, CA, 92037, USA
| | - Maxim M. Totrov
- Molsoft LLC, 3366 North Torrey Pines Court, Suite 300, La Jolla, CA, 92037, USA
| | - Paul R. Carlier
- Department of Chemistry, Virginia Tech, Blacksburg, VA, 24061, USA
| | - Adalberto A. Pérez de León
- Knipling-Bushland U.S. Livestock Insects Research Laboratory, United States Department of Agricultural-Agricultural Research Service, 2700 Fredericksburg Road, Kerrville, TX, 78028, USA
| | - Jeffrey R. Bloomquist
- Department of Entomology and Nematology, Emerging Pathogens Institute, University of Florida, Gainesville, FL, 32611, USA
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Temeyer KB, Tuckow AP, Brake DK, Li AY, Pérez de León AA. Acetylcholinesterases of blood-feeding flies and ticks. Chem Biol Interact 2013; 203:319-22. [DOI: 10.1016/j.cbi.2012.09.010] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Revised: 09/11/2012] [Accepted: 09/19/2012] [Indexed: 12/31/2022]
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Zhao P, Wang Y, Jiang H. Biochemical properties, expression profiles, and tissue localization of orthologous acetylcholinesterase-2 in the mosquito, Anopheles gambiae. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2013; 43:260-271. [PMID: 23267863 PMCID: PMC3578101 DOI: 10.1016/j.ibmb.2012.12.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Revised: 12/06/2012] [Accepted: 12/14/2012] [Indexed: 06/01/2023]
Abstract
Acetylcholinesterases (AChEs) catalyze the hydrolysis of acetylcholine, a neurotransmitter for cholinergic neurotransmission in animals. Most insects studied so far possess two AChE genes: ace-1 paralogous and ace-2 orthologous to Drosophila melanogaster ace. We characterized the catalytic domain of Anopheles gambiae AChE1 in a previous study (Jiang et al., 2009) and report here biochemical properties of A. gambiae AChE2 expressed in Sf9 cells. An unknown protease in the expression system cleaved the recombinant AChE2 next to Arg(110), yielding two non-covalently associated polypeptides. A mixture of the intact and cleaved AChE2 had a specific activity of 72.3 U/mg, much lower than that of A. gambiae AChE1 (523 U/mg). The order of V(max)/K(M) values for the model substrates was acetylthiocholine > propionylthiocholine ≈ acetyl-(β-methyl)thiocholine > butyrylthiocholine. The IC(50)'s for eserine, carbaryl, BW284C51, paraoxon and malaoxon were 1.32, 13.6, 26.8, 192 and 294 nM, respectively. A. gambiae AChE2 bound eserine and carbaryl stronger than paraoxon and malaoxon, whereas eserine and malaoxon modified the active site Ser(232) faster than carbaryl or paraoxon did. Consequently, the k(i)'s were 1.173, 0.245, 0.029 and 0.018 μM(-1)min(-1) for eserine, carbaryl, paraoxon and malaoxon, respectively. Quantitative polymerase chain reactions showed a similar pattern of ace-1 and ace-2 expression. Their mRNAs were abundant in early embryos, greatly decreased in late embryos, larvae, pupae, and pharate adult, and became abundant again in adults. Both transcripts were higher in head and abdomen than thorax of adults and higher in male than female mosquitoes. Transcript levels of ace-1 were 1.9- to 361.8-fold higher than those of ace-2, depending on developmental stages and body parts. Cross-reacting polyclonal antibodies detected AChEs in adult brains, thoracic ganglia, and genital/rectal area. Activity assays, immunoblotting, and tandem mass spectrometric analysis indicated that A. gambiae AChE1 is responsible for most of acetylthiocholine hydrolysis in the head extracts. Taken together, these data indicate that A. gambiae AChE2 may play a less significant role than AChE1 does in the mosquito nervous system.
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Affiliation(s)
- Picheng Zhao
- Department of Entomology and Plant Pathology, Oklahoma State University, Stillwater, OK 74078, USA
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Temeyer KB, Brake DK, Schlechte KG. Acetylcholinesterase of Haematobia irritans (Diptera: Muscidae): baculovirus expression, biochemical properties, and organophosphate insensitivity of the G262A mutant. JOURNAL OF MEDICAL ENTOMOLOGY 2012; 49:589-594. [PMID: 22679866 DOI: 10.1603/me11211] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
This study reports the baculovirus expression and biochemical characterization of recombinant acetylcholinesterase from Haematobia irritans (L.) (rHiAChE) and the effect of the previously described G262A mutation on enzyme activity and sensitivity to selected organophosphates. The rHiAChE was confirmed to be an insect AChE2-type enzyme with substrate preference for acetylthiocholine (Km 31.3 microM) over butyrylthiocholine (Km 63.4 microM) and inhibition at high substrate concentration. Enzyme activity was strongly inhibited by eserine (2.3 x 10(-10) M), BW284c51 (3.4 x 10(-8) M), malaoxon (3.6 x 10(-9) M), and paraoxon (1.8 x 10(-7) M), and was less sensitive to the butyrylcholinesterase inhibitors ethopropazine (1.1 x 10(-6) M) and iso-OMPA (4.1 x 10(-4) M). rHiAChE containing the G262A substitution exhibited decreased substrate affinity for both acetylthiocholine (Km 40.9 microM) and butyrylthiocholine (Km 96.3 microM), and exhibited eight-fold decreased sensitivity to paraoxon, and approximately 1.5- to 3-fold decreased sensitivity to other inhibitors. The biochemical kinetics are consistent with previously reported bioassay analysis, suggesting that the G262A mutation contributes to, but is not solely responsible for observed phenotypic resistance to diazinon or other organophosphates.
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Affiliation(s)
- Kevin B Temeyer
- Knipling-Bushland U.S. Livestock Insects Research Laboratory, USDA-ARS, 2700 Fredericksburg Road, Kerrville, TX 78028, USA.
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Guerrero FD, Lovis L, Martins JR. Acaricide resistance mechanisms in Rhipicephalus (Boophilus) microplus. REVISTA BRASILEIRA DE PARASITOLOGIA VETERINARIA = BRAZILIAN JOURNAL OF VETERINARY PARASITOLOGY : ORGAO OFICIAL DO COLEGIO BRASILEIRO DE PARASITOLOGIA VETERINARIA 2012; 21:1-6. [PMID: 22534937 DOI: 10.1590/s1984-29612012000100002] [Citation(s) in RCA: 123] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2012] [Accepted: 03/05/2012] [Indexed: 11/21/2022]
Abstract
Acaricide resistance has become widespread in countries where cattle ticks, Rhipicephalus (Boophilus) microplus, are a problem. Resistance arises through genetic changes in a cattle tick population that causes modifications to the target site, increased metabolism or sequestration of the acaricide, or reduced ability of the acaricide to penetrate through the outer protective layers of the tick's body. We review the molecular and biochemical mechanisms of acaricide resistance that have been shown to be functional in R. (B.) microplus. From a mechanistic point of view, resistance to pyrethroids has been characterized to a greater degree than any other acaricide class. Although a great deal of research has gone into discovery of the mechanisms that cause organophosphate resistance, very little is defined at the molecular level and organophosphate resistance seems to be maintained through a complex and multifactorial process. The resistance mechanisms for other acaricides are less well understood. The target sites of fipronil and the macrocyclic lactones are known and resistance mechanism studies are in the early stages. The target site of amitraz has not been definitively identified and this is hampering mechanistic studies on this acaricide.
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Affiliation(s)
- Felix David Guerrero
- Knipling-Bushland U.S. Livestock Insects Research Lab, United States Department of Agriculture, Fredericksburg Rd., 78006, Kerrville, TX, USA.
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Klafke GM, Castro-Janer E, Mendes MC, Namindome A, Schumaker TTS. Applicability of in vitro bioassays for the diagnosis of ivermectin resistance in Rhipicephalus microplus (Acari: Ixodidae). Vet Parasitol 2011; 184:212-20. [PMID: 21978742 DOI: 10.1016/j.vetpar.2011.09.018] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2011] [Revised: 09/09/2011] [Accepted: 09/12/2011] [Indexed: 10/17/2022]
Abstract
The applicability of laboratory bioassays to diagnose ivermectin (IVM) resistance in Rhipicephalus microplus was evaluated. Adult immersion tests (AITs), larval immersion tests (LITs) and larval packet tests (LPTs) were performed to characterise the effects of ivermectin toxicity on adults and larvae of a susceptible reference strain. The AIT was determined to be a reasonable assay but requires a large number of individuals to attain interpretable results. The LIT and LPT were validated with an IVM resistant strain, revealing resistance ratios (RRs) of 6.73 and 1.49, respectively. In a field survey, nine different populations of cattle tick from the states of São Paulo and Mato Grosso do Sul, Brazil, were analysed with the LIT. Populations without previous exposure to ivermectin exhibited RRs between 0.87 and 1.01. Populations previously exposed to IVM showed RRs between 1.83 and 4.62. The LIT was more effective at discriminating between resistant and susceptible populations than the LPT. The use of the LIT is recommended for the diagnosis of ivermectin resistance in R. microplus.
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Affiliation(s)
- G M Klafke
- Departamento de Parasitologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, Av. Prof. Lineu Prestes, 1374, 05508-900 São Paulo, Brazil.
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