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Xu X, Wang Y, Bi H, Xu J, Liu Z, Niu C, He L, James AA, Li K, Huang Y. Mutation of the seminal protease gene, serine protease 2, results in male sterility in diverse lepidopterans. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2020; 116:103243. [PMID: 31541694 DOI: 10.1016/j.ibmb.2019.103243] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Revised: 09/04/2019] [Accepted: 09/14/2019] [Indexed: 06/10/2023]
Abstract
Sterile insect technology (SIT) is an environmentally friendly method for pest control. As part of our efforts to develop a strategy that results in engineered male-sterile strains with minimum effects on viability and mating competition, we used CRISPR/Cas9 technology to disrupt Ser2, which encodes a seminal fluid protein, in the model lepidopteran insect, Bombyx mori, and an important agricultural pest, Plutella xylostella. Disruption of Ser2 resulted in dominant heritable male sterility. Wild-type females mated with Ser2-deficient males laid eggs normally, but the eggs did not hatch. We detected no differences in other reproductive behaviors in the mutant males. These results support the conclusion that Ser2 gene is necessary for male reproductive success in diverse lepidopterans. Targeting Ser2 gene has the potential to form the basis for a new strategy for pest control.
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Affiliation(s)
- Xia Xu
- School of Life Science, East China Normal University, 200241, Shanghai, China; Key Laboratory of Insect Developmental and Evolutionary Biology, Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, 200032, Shanghai, China
| | - Yaohui Wang
- Key Laboratory of Insect Developmental and Evolutionary Biology, Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, 200032, Shanghai, China; Hubei Key Laboratory of Insect Resource Application and Sustainable Pest Control, College of Plant Science & Technology, Huazhong Agricultural University, 430070, Wuhan, China
| | - Honglun Bi
- School of Life Science, East China Normal University, 200241, Shanghai, China; Key Laboratory of Insect Developmental and Evolutionary Biology, Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, 200032, Shanghai, China
| | - Jun Xu
- Key Laboratory of Insect Developmental and Evolutionary Biology, Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, 200032, Shanghai, China
| | - Zulian Liu
- Key Laboratory of Insect Developmental and Evolutionary Biology, Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, 200032, Shanghai, China
| | - Changying Niu
- Hubei Key Laboratory of Insect Resource Application and Sustainable Pest Control, College of Plant Science & Technology, Huazhong Agricultural University, 430070, Wuhan, China
| | - Lin He
- School of Life Science, East China Normal University, 200241, Shanghai, China.
| | - Anthony A James
- Department of Microbiology & Molecular Genetics and Molecular Biology & Biochemistry, University of California, Irvine, CA, 92697-3900, USA
| | - Kai Li
- School of Life Science, East China Normal University, 200241, Shanghai, China.
| | - Yongping Huang
- Key Laboratory of Insect Developmental and Evolutionary Biology, Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, 200032, Shanghai, China.
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Suresh M, Jeevanandam J, Chan YS, Danquah MK, Kalaiarasi JMV. Opportunities for Metal Oxide Nanoparticles as a Potential Mosquitocide. BIONANOSCIENCE 2019. [DOI: 10.1007/s12668-019-00703-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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103
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Anderson ME, Mavica J, Shackleford L, Flis I, Fochler S, Basu S, Alphey L. CRISPR/Cas9 gene editing in the West Nile Virus vector, Culex quinquefasciatus Say. PLoS One 2019; 14:e0224857. [PMID: 31714905 PMCID: PMC6850532 DOI: 10.1371/journal.pone.0224857] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Accepted: 10/23/2019] [Indexed: 12/16/2022] Open
Abstract
Culex quinquefasciatus Say is an opportunistic blood feeder with a wide geographic distribution which is also a major vector for a range of diseases of both animals and humans. CRISPR/Cas technologies have been applied to a wide variety of organisms for both applied and basic research purposes. CRISPR/Cas methods open new possibilities for genetic research in non-model organisms of public health importance. In this work we have adapted microinjection techniques commonly used in other mosquito species to Culex quinquefasciatus, and have shown these to be effective at generating homozygous knock-out mutations of a target gene in one generation. This is the first description of the kmo gene and mutant phenotype in this species.
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Affiliation(s)
- Michelle E. Anderson
- Arthropod Genetics, The Pirbright Institute, Pirbright, Woking, England, United Kingdom
| | - Jessica Mavica
- Arthropod Genetics, The Pirbright Institute, Pirbright, Woking, England, United Kingdom
| | - Lewis Shackleford
- Arthropod Genetics, The Pirbright Institute, Pirbright, Woking, England, United Kingdom
| | - Ilona Flis
- Arthropod Genetics, The Pirbright Institute, Pirbright, Woking, England, United Kingdom
| | - Sophia Fochler
- Arthropod Genetics, The Pirbright Institute, Pirbright, Woking, England, United Kingdom
| | - Sanjay Basu
- Arthropod Genetics, The Pirbright Institute, Pirbright, Woking, England, United Kingdom
| | - Luke Alphey
- Arthropod Genetics, The Pirbright Institute, Pirbright, Woking, England, United Kingdom
- * E-mail:
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Chen W, Yang F, Xu X, Kumar U, He W, You M. Genetic control of Plutella xylostella in omics era. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2019; 102:e21621. [PMID: 31538676 DOI: 10.1002/arch.21621] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 08/14/2019] [Accepted: 09/02/2019] [Indexed: 06/10/2023]
Abstract
Diamondback moth, Plutella xylostella (L.), is a specialist pest on cruciferous crops of economic importance. The large-scale use of chemical insecticides for the control of this insect pest has caused a number of challenges to agro-ecosystems. With the advent of the omics era, genetic pest management strategies are becoming increasingly feasible and show a powerful potential for pest control. Here, we review strategies for using transgenic plants and sterile insect techniques for genetic pest management and introduce the major advances in the control of P. xylostella using a female-specific RIDL (release of insects carrying a dominant lethal gene) strategy. Further, the advantages of gene drive developed in combination with sex determination and CRISPR/Cas9 systems are addressed, and the corresponding prospects and implementation issues are discussed. It is predictable that under the policy and regulation of professional committees, the genetic pest control strategy, especially for gene drive, will open a new avenue to sustainable pest management not only for P. xylostella but also for other insect pests.
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Affiliation(s)
- Wei Chen
- State Key Laboratory for Ecological Pest Control of Fujian and Taiwan Crops, Institute of Applied Ecology, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China
- International Joint Research Laboratory of Ecological Pest Control, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Feiying Yang
- State Key Laboratory for Ecological Pest Control of Fujian and Taiwan Crops, Institute of Applied Ecology, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China
- International Joint Research Laboratory of Ecological Pest Control, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Xuejiao Xu
- State Key Laboratory for Ecological Pest Control of Fujian and Taiwan Crops, Institute of Applied Ecology, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China
- International Joint Research Laboratory of Ecological Pest Control, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Uttam Kumar
- State Key Laboratory for Ecological Pest Control of Fujian and Taiwan Crops, Institute of Applied Ecology, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China
- International Joint Research Laboratory of Ecological Pest Control, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Weiyi He
- State Key Laboratory for Ecological Pest Control of Fujian and Taiwan Crops, Institute of Applied Ecology, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China
- International Joint Research Laboratory of Ecological Pest Control, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Minsheng You
- State Key Laboratory for Ecological Pest Control of Fujian and Taiwan Crops, Institute of Applied Ecology, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China
- International Joint Research Laboratory of Ecological Pest Control, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China
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105
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Edgington MP, Alphey LS. Modeling the mutation and reversal of engineered underdominance gene drives. J Theor Biol 2019; 479:14-21. [PMID: 31260669 PMCID: PMC6699728 DOI: 10.1016/j.jtbi.2019.06.024] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 06/24/2019] [Accepted: 06/27/2019] [Indexed: 01/31/2023]
Abstract
A range of gene drive systems have been proposed that are predicted to increase their frequency and that of associated desirable genetic material even if they confer a fitness cost on individuals carrying them. Engineered underdominance (UD) is such a system and, in one version, is based on the introduction of two independently segregating transgenic constructs each carrying a lethal gene, a suppressor for the lethal at the other locus and a desirable genetic "cargo". Under this system individuals carrying at least one copy of each construct (or no copies of either) are viable whilst those that possess just one of the transgenic constructs are non-viable. Previous theoretical work has explored various properties of these systems, concluding that they should persist indefinitely in absence of resistance or mutation. Here we study a population genetics model of UD gene drive that relaxes past assumptions by allowing for loss-of-function mutations in each introduced gene. We demonstrate that mutations are likely to cause UD systems to break down, eventually resulting in the elimination of introduced transgenes. We then go on to investigate the potential of releasing "free suppressor" carrying individuals as a new method for reversing UD gene drives and compare this to the release of wild-types; the only previously proposed reversal strategy for UD. This reveals that while free suppressor carrying individuals may represent an inexpensive reversal strategy due to extremely small release requirements, they are not able to return a fully wild-type population as rapidly as the release of wild-types.
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Affiliation(s)
| | - Luke S Alphey
- The Pirbright Institute, Ash Road, Woking, Surrey GU24 0NF, UK
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106
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Engineered action at a distance: Blood-meal-inducible paralysis in Aedes aegypti. PLoS Negl Trop Dis 2019; 13:e0007579. [PMID: 31479450 PMCID: PMC6719823 DOI: 10.1371/journal.pntd.0007579] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Accepted: 06/26/2019] [Indexed: 11/23/2022] Open
Abstract
Background Population suppression through mass-release of Aedes aegypti males carrying dominant-lethal transgenes has been demonstrated in the field. Where population dynamics show negative density-dependence, suppression can be enhanced if lethality occurs after the density-dependent (i.e. larval) stage. Existing molecular tools have limited current examples of such Genetic Pest Management (GPM) systems to achieving this through engineering ‘cell-autonomous effectors’ i.e. where the expressed deleterious protein is restricted to the cells in which it is expressed–usually under the control of the regulatory elements (e.g. promoter regions) used to build the system. This limits the flexibility of these technologies as regulatory regions with useful spatial, temporal or sex-specific expression patterns may only be employed if the cells they direct expression in are simultaneously sensitive to existing effectors, and also precludes the targeting of extracellular regions such as cell-surface receptors. Expanding the toolset to ‘non-cell autonomous’ effectors would significantly reduce these limitations. Methodology/Principal findings We sought to engineer female-specific, late-acting lethality through employing the Ae. aegypti VitellogeninA1 promoter to drive blood-meal-inducible, fat-body specific expression of tTAV. Initial attempts using pro-apoptotic effectors gave no evident phenotype, potentially due to the lower sensitivity of terminally-differentiated fat-body cells to programmed-death signals. Subsequently, we dissociated the temporal and spatial expression of this system by engineering a novel synthetic effector (Scorpion neurotoxin–TetO-gp67.AaHIT) designed to be secreted out of the tissue in which it was expressed (fat-body) and then affect cells elsewhere (neuro-muscular junctions). This resulted in a striking, temporary-paralysis phenotype after blood-feeding. Conclusions/Significance These results are significant in demonstrating for the first time an engineered ‘action at a distance’ phenotype in a non-model pest insect. The potential to dissociate temporal and spatial expression patterns of useful endogenous regulatory elements will extend to a variety of other pest insects and effectors. A recent addition to the toolbox for controlling populations of the disease vector Aedes aegypti is the mass-release of males engineered with dominant, lethal transgenes. The lethal effect of these transgenes is activated in the progeny of these released engineered males and wild females they mate with in the field and with continuous release of males can cause population collapse. To date, these systems have relied on the use of ‘cell-autonomous’ effectors, meaning that their action is restricted to the cells in which they are expressed, limiting the flexibility of designing new, more complex systems. Here we demonstrate that it is possible to engineer ‘non-cell autonomous’ effectors–that is where the effect (e.g. the action of a toxic protein) can act on cells distant from the tissues in which they are originally expressed. To achieve this we utilised the endogenous cell secretory pathway to engineer a novel control phenotype–blood-meal inducible (i.e. late-acting, female-specific) reversible paralysis. The logic behind engineering such ‘action at a distance’ phenotypes will extend to a variety of other pest insects and control phenotypes.
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107
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Staunton KM, Usher L, Prachar T, Ritchie SA, Snoad N, Johnson BJ. A Novel Methodology For Recording Wing Beat Frequencies of Untethered Male and Female Aedes aegypti. JOURNAL OF THE AMERICAN MOSQUITO CONTROL ASSOCIATION 2019; 35:169-177. [PMID: 31647706 DOI: 10.2987/18-6799.1] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Aedes aegypti is a vector of many significant arboviruses worldwide, including dengue, Zika, chikungunya, and yellow fever viruses. With vector control methodology pivoting toward rearing and releasing large numbers of insects for either population suppression or virus-blocking, economical remote (sentinel) surveillance methods for release tracking become increasingly necessary. Recent steps in this direction include advances in optical sensors that identify and classify insects based on their wing beat frequency (WBF). As these traps are being developed, there is a strong need to better understand the environmental and biological factors influencing mosquito WBFs. Here, we developed new untethered-subject methodology to detect changes in WBFs of male and female Ae. aegypti. This new methodology involves directing an ultrasonic transducer at a free-flying subject and measuring the Doppler shift of the reflected ultrasonic continuous wave signal. This system's utility was assessed by determining its ability to confirm previous reports on the effect of temperature, body size, and age on the WBFs generated from acoustic or optical-based experiments. The presented ultrasonic method successfully detected expected trends for each factor for both male and female Ae. aegypti without the need for subject manipulation and potential impediment of natural flight dynamics due to tethering. As a result, this ultrasonic methodology provides a new method for understanding the environmental and physiological determinants of male and female WBFs that can inform the design of remote mosquito surveillance systems.
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108
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Climatic Conditions: Conventional and Nanotechnology-Based Methods for the Control of Mosquito Vectors Causing Human Health Issues. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2019; 16:ijerph16173165. [PMID: 31480254 PMCID: PMC6747303 DOI: 10.3390/ijerph16173165] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 08/25/2019] [Accepted: 08/27/2019] [Indexed: 12/12/2022]
Abstract
Climate variability is highly impacting on mosquito-borne diseases causing malaria and dengue fever across the globe. Seasonal variability change in temperature and rainfall patterns are impacting on human health. Mosquitoes cause diseases like dengue fever, yellow fever, malaria, Chikungunya, West Nile and Japanese encephalitis. According to estimations by health organizations, annually one million human deaths are caused by vector-borne diseases, and dengue fever has increased about 30-fold over the past 50 years. Similarly, over 200 million cases of malaria are being reported annually. Mosquito-borne diseases are sensitive to temperature, humidity and seasonal variability. Both conventional (environmental, chemical, mechanical, biological etc.) and nanotechnology-based (Liposomes, nano-suspensions and polymer-based nanoparticles) approaches are used for the eradication of Malaria and dengue fever. Now green approaches are used to eradicate mosquitoes to save human health without harming the environment. In this review, the impact of climatic conditions on mosquito-borne diseases along with conventional and nanotechnology-based approaches used for controlling malaria and dengue fever have been discussed. Important recommendations have been made for people to stay healthy.
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109
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Lutrat C, Giesbrecht D, Marois E, Whyard S, Baldet T, Bouyer J. Sex Sorting for Pest Control: It's Raining Men! Trends Parasitol 2019; 35:649-662. [PMID: 31255488 DOI: 10.1016/j.pt.2019.06.001] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2019] [Revised: 05/30/2019] [Accepted: 06/01/2019] [Indexed: 12/16/2022]
Abstract
In the pursuit of better pest- and vector-control strategies, attention returns to an old proven technology, the sterile insect technique (SIT) and related insect population-suppression methods. A major obstacle for any of these approaches that involves the release of sterile males is the separation of males from females during the mass rearing stage, in order to improve the cost-efficiency of these methods and to prevent the release of biting and disease-vectoring females. This review describes recent sex-sorting developments in dipteran flies with an emphasis on assessing the suitability of these methods for large-scale rearing of male vectors for mass release.
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Affiliation(s)
- Célia Lutrat
- CIRAD, UMR ASTRE, F-34398, Montpellier, France; ASTRE, CIRAD, INRA, Univ Montpellier, Montpellier, France; Université de Montpellier, Montpellier, France
| | - David Giesbrecht
- Department of Biological Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - Eric Marois
- CNRS UPR9022, INSERM U963, Institut de Biologie Moléculaire et Cellulaire, Université de Strasbourg, Strasbourg, France
| | - Steve Whyard
- Department of Biological Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - Thierry Baldet
- CIRAD, UMR ASTRE, F-34398, Montpellier, France; ASTRE, CIRAD, INRA, Univ Montpellier, Montpellier, France
| | - Jérémy Bouyer
- CIRAD, UMR ASTRE, F-34398, Montpellier, France; Insect Pest Control, Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, International Atomic Energy Agency (IAEA), Vienna, Austria. @cirad.fr
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110
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Pleydell DRJ, Bouyer J. Biopesticides improve efficiency of the sterile insect technique for controlling mosquito-driven dengue epidemics. Commun Biol 2019; 2:201. [PMID: 31149645 PMCID: PMC6541632 DOI: 10.1038/s42003-019-0451-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Accepted: 04/30/2019] [Indexed: 12/16/2022] Open
Abstract
Various mosquito control methods use factory raised males to suppress vector densities. But the efficiency of these methods is currently insufficient to prevent epidemics of arbovirus diseases such as dengue, chikungunya or Zika. Suggestions that the sterile insect technique (SIT) could be "boosted" by applying biopesticides to sterile males remain unquantified. Here, we assess mathematically the gains to SIT for Aedes control of either: boosting with the pupicide pyriproxifen (BSIT); or, contaminating mosquitoes at auto-dissemination stations. Thresholds in sterile male release rate and competitiveness are identified, above which mosquitoes are eliminated asymptotically. Boosting reduces these thresholds and aids population destabilisation, even at sub-threshold release rates. No equivalent bifurcation exists in the auto-dissemination sub-model. Analysis suggests that BSIT can reduce by over 95% the total release required to circumvent dengue epidemics compared to SIT. We conclude, BSIT provides a powerful new tool for the integrated management of mosquito borne diseases.
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Affiliation(s)
- David R. J. Pleydell
- CIRAD, INRA, University of Montpellier, UMR ASTRE, F-34398 Montpellier, France
- INRA, CIRAD, University of Montpellier, UMR ASTRE, F-97170 Petit Bourg Guadeloupe, France
| | - Jérémy Bouyer
- CIRAD, INRA, University of Montpellier, UMR ASTRE, F-34398 Montpellier, France
- Insect Pest Control Laboratory, Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, IAEA, Vienna, Austria
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111
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Frieß JL, von Gleich A, Giese B. Gene drives as a new quality in GMO releases-a comparative technology characterization. PeerJ 2019; 7:e6793. [PMID: 31110918 PMCID: PMC6501761 DOI: 10.7717/peerj.6793] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Accepted: 03/15/2019] [Indexed: 01/10/2023] Open
Abstract
Compared to previous releases of genetically modified organisms (GMOs) which were primarily plants, gene drives represent a paradigm shift in the handling of GMOs: Current regulation of the release of GMOs assumes that for specific periods of time a certain amount of GMOs will be released in a particular region. However, now a type of genetic technology arises whose innermost principle lies in exceeding these limits-the transformation or even eradication of wild populations. The invasive character of gene drives demands a thorough analysis of their functionalities, reliability and potential impact. But such investigations are hindered by the fact that an experimental field test would hardly be reversible. Therefore, an appropriate prospective assessment is of utmost importance for an estimation of the risk potential associated with the application of gene drives. This work is meant to support the inevitable characterization of gene drives by a comparative approach of prospective technology assessment with a focus on potential sources of risk. Therein, the hazard and exposure potential as well as uncertainties with regard to the performance of synthetic gene drives are addressed. Moreover, a quantitative analysis of their invasiveness should enable a differentiated evaluation of their power to transform wild populations.
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Affiliation(s)
- Johannes L. Frieß
- Institute for Safety/Security and Risk Sciences, University of Natural Resources and Life Sciences, Vienna (BOKU), Austria
| | - Arnim von Gleich
- Department of Technology Design and Development, Faculty of Production Engineering, University of Bremen, Germany
| | - Bernd Giese
- Institute for Safety/Security and Risk Sciences, University of Natural Resources and Life Sciences, Vienna (BOKU), Austria
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112
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Taracena ML, Hunt CM, Benedict MQ, Pennington PM, Dotson EM. Downregulation of female doublesex expression by oral-mediated RNA interference reduces number and fitness of Anopheles gambiae adult females. Parasit Vectors 2019; 12:170. [PMID: 30992032 PMCID: PMC6466716 DOI: 10.1186/s13071-019-3437-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Accepted: 04/05/2019] [Indexed: 12/21/2022] Open
Abstract
Background Mosquito-borne diseases affect millions worldwide, with malaria alone killing over 400 thousand people per year and affecting hundreds of millions. To date, the best strategy to prevent the disease remains insecticide-based mosquito control. However, insecticide resistance as well as economic and social factors reduce the effectiveness of the current methodologies. Alternative control technologies are in development, including genetic control such as the sterile insect technique (SIT). The SIT is a pivotal tool in integrated agricultural pest management and could be used to improve malaria vector control. To apply the SIT and most other newer technologies against disease transmitting mosquitoes, it is essential that releases are composed of males with minimal female contamination. The removal of females is an essential requirement because released females can themselves contribute towards nuisance biting and disease transmission. Thus, females need to be eliminated from the cohorts prior to release. Manual separation of Anopheles gambiae pupae or adult mosquitoes based on morphology is time consuming, is not feasible on a large scale and has limited the implementation of the SIT technique. The doublesex (dsx) gene is one of the effector switches of sex determination in the process of sex differentiation in insects. Both males and females have specific splicing variants that are expressed across the different life stages. Using RNA interference (RNAi) to reduce expression of the female specific (dsxF) variant of this gene has proven to have detrimental effects to the females in other mosquito species, such as Aedes aegypti. We tested oral RNAi on dsx (AgdsxF) in An. gambiae. Methods We studied the expression pattern of the dsx gene in the An. gambiae G3 strain. We knocked down AgdsxF expression in larvae through oral delivery of double stranded RNA (dsRNA) produced by bacteria and observed its effects in adults. Results Our results show that feeding of AgdsxF dsRNA can effectively reduce (> 66%) the mRNA of female dsx transcript and that there is a concomitant reduction in the number of female larvae that achieve adulthood. Control groups produced 52% (± 3.9% SE) of adult males and 48% (± 4.0% SE) females, while AgdsxF dsRNA treated groups had 72.1% (± 4.0% SE) males vs 27.8% females (± 3.3% SE). In addition, the female adults produce fewer progeny, 37.1% (± 8.2% SE) less than the controls. The knockdown was sex-specific and had no impact on total numbers of viable male adults, in the male dsx transcripts or male fitness parameters such as longevity or body size. Conclusions These findings indicate that RNAi could be used to improve novel mosquito control strategies that require efficient sex separation and male-only release of An. gambiae by targeting sex determination genes such as AgdsxF. The advantages of using RNAi in a controlled setting for mosquito rearing are numerous, as the dose and time of exposure are controlled, and the possibility of off-target effects and the waste of female production would be significantly reduced. Electronic supplementary material The online version of this article (10.1186/s13071-019-3437-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Mabel L Taracena
- Centers for Disease Control and Prevention (CDC), 1600 Clifton Road, NE, Atlanta, GA, 30329-4027, MS G49, USA.
| | - Catherine M Hunt
- Centers for Disease Control and Prevention (CDC), 1600 Clifton Road, NE, Atlanta, GA, 30329-4027, MS G49, USA
| | - Mark Q Benedict
- Centers for Disease Control and Prevention (CDC), 1600 Clifton Road, NE, Atlanta, GA, 30329-4027, MS G49, USA
| | - Pamela M Pennington
- Centro de Estudios en Biotecnologia, Universidad del Valle de Guatemala, 18 Avenida 11-95, 01015, Guatemala City, Guatemala
| | - Ellen M Dotson
- Centers for Disease Control and Prevention (CDC), 1600 Clifton Road, NE, Atlanta, GA, 30329-4027, MS G49, USA
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113
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Epopa PS, Collins CM, North A, Millogo AA, Benedict MQ, Tripet F, Diabate A. Seasonal malaria vector and transmission dynamics in western Burkina Faso. Malar J 2019; 18:113. [PMID: 30940141 PMCID: PMC6444393 DOI: 10.1186/s12936-019-2747-5] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Accepted: 03/25/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND In the context of widespread mosquito resistance to currently available pesticides, novel, precise genetic vector control methods aimed at population suppression or trait replacement are a potentially powerful approach that could complement existing malaria elimination interventions. Such methods require knowledge of vector population composition, dynamics, behaviour and role in transmission. Here were characterized these parameters in three representative villages, Bana, Pala and Souroukoudingan, of the Sudano-Sahelian belt of Burkina Faso, a region where bed net campaigns have recently intensified. METHODS From July 2012 to November 2015, adult mosquitoes were collected monthly using pyrethroid spray catches (PSC) and human landing catches (HLC) in each village. Larval habitat prospections assessed breeding sites abundance at each site. Mosquitoes collected by PSC were identified morphologically, and then by molecular technique to species where required, to reveal the seasonal dynamics of local vectors. Monthly entomological inoculation rates (EIR) that reflect malaria transmission dynamics were estimated by combining the HLC data with mosquito sporozoite infection rates (SIR) identified through ELISA-CSP. Finally, population and EIR fluctuations were fit to locally-collected rainfall data to highlight the strong seasonal determinants of mosquito abundance and malaria transmission in this region. RESULTS The principal malaria vectors found were in the Anopheles gambiae complex. Mosquito abundance peaked during the rainy season, but there was variation in vector species composition between villages. Mean survey HLC and SIR were similar across villages and ranged from 18 to 48 mosquitoes/person/night and from 3.1 to 6.6% prevalence. The resulting monthly EIRs were extremely high during the rainy season (0.91-2.35 infectious bites/person/day) but decreased substantially in the dry season (0.03-0.22). Vector and malaria transmission dynamics generally tracked seasonal rainfall variations, and the highest mosquito abundances and EIRs occurred in the rainy season. However, despite low residual mosquito populations, mosquitoes infected with malaria parasites remained present in the dry season. CONCLUSION These results highlight the important vector control challenge facing countries with high EIR despite the recent campaigns of bed net distribution. As demonstrated in these villages, malaria transmission is sustained for large parts of the year by a very high vector abundance and high sporozoite prevalence, resulting in seasonal patterns of hyper and hypo-endemicity. There is, therefore, an urgent need for additional vector control tools that can target endo and exophillic mosquito populations.
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Affiliation(s)
- Patric Stephane Epopa
- Institut de Recherche en Sciences de la santé/Centre Muraz, Bobo-Dioulasso, Burkina Faso.
| | | | - Ace North
- Department of Zoology, University of Oxford, Oxford, UK
| | | | | | - Frederic Tripet
- Centre for Applied Entomology and Parasitology, School of Life Sciences, Keele University, Staffordshire, UK
| | - Abdoulaye Diabate
- Institut de Recherche en Sciences de la santé/Centre Muraz, Bobo-Dioulasso, Burkina Faso
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114
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Zheng W, Li Q, Sun H, Ali MW, Zhang H. Clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated 9-mediated mutagenesis of the multiple edematous wings gene induces muscle weakness and flightlessness in Bactrocera dorsalis (Diptera: Tephritidae). INSECT MOLECULAR BIOLOGY 2019; 28:222-234. [PMID: 30260055 DOI: 10.1111/imb.12540] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated 9 (Cas9) system is a versatile, efficient and heritable gene editing tool that can be useful for genome engineering. Bactrocera dorsalis (Hendel) is a major pest of agriculture that causes great economic losses. We used the B. dorsalis multiple edematous wings (Bdmew) gene as the target gene to explore the effectiveness of CRISPR/Cas9 for B. dorsalis genome manipulation. We studied the physiological functions of the Bdmew gene, particularly those related to muscle development. Site-specific genome editing was feasible using direct microinjection of specific guide RNA and the Cas9-plasmid into B. dorsalis embryos. Mutation frequencies ranged from 12.1 to 30.2% in the injected generation. Mosaic G0, with the mew mutation, was heritable to the next generation. The G1 displayed a series of defective phenotypes including muscle weakness, flightlessness, failure to eclose, wing folds and unbalanced movement. These results demonstrated that CRISPR/Cas9 can act as a highly specific, efficient, heritable tool for genome manipulation in B. dorsalis and this has significance for gene function research and genetic control of pests. The Bdmew gene possesses key functions in muscle development of B. dorsalis. Bdmew mutations cause a series of serious defects by interfering with muscle development and may provide a means for controlling B. dorsalis via a gene-based method such as gene drive.
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Affiliation(s)
- W Zheng
- Key Laboratory of Horticultural Plant Biology (MOE), State Key Laboratory of Agricultural Microbiology, China-Australia Joint Research Center for Horticultural and Urban Pests, Institute of Urban and Horticultural Entomology, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Q Li
- Key Laboratory of Horticultural Plant Biology (MOE), State Key Laboratory of Agricultural Microbiology, China-Australia Joint Research Center for Horticultural and Urban Pests, Institute of Urban and Horticultural Entomology, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - H Sun
- Key Laboratory of Horticultural Plant Biology (MOE), State Key Laboratory of Agricultural Microbiology, China-Australia Joint Research Center for Horticultural and Urban Pests, Institute of Urban and Horticultural Entomology, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - M Waqar Ali
- Key Laboratory of Horticultural Plant Biology (MOE), State Key Laboratory of Agricultural Microbiology, China-Australia Joint Research Center for Horticultural and Urban Pests, Institute of Urban and Horticultural Entomology, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - H Zhang
- Key Laboratory of Horticultural Plant Biology (MOE), State Key Laboratory of Agricultural Microbiology, China-Australia Joint Research Center for Horticultural and Urban Pests, Institute of Urban and Horticultural Entomology, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
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115
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Collins CM, Bonds JAS, Quinlan MM, Mumford JD. Effects of the removal or reduction in density of the malaria mosquito, Anopheles gambiae s.l., on interacting predators and competitors in local ecosystems. MEDICAL AND VETERINARY ENTOMOLOGY 2019; 33:1-15. [PMID: 30044507 PMCID: PMC6378608 DOI: 10.1111/mve.12327] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 05/23/2018] [Accepted: 06/15/2018] [Indexed: 05/23/2023]
Abstract
New genetic control methods for mosquitoes may reduce vector species without direct effects on other species or the physical environment common with insecticides or drainage. Effects on predators and competitors could, however, be a concern as Anopheles gambiae s.l. is preyed upon in all life stages. We overview the literature and assess the strength of the ecological interactions identified. Most predators identified consume many other insect species and there is no evidence that any species preys exclusively on any anopheline mosquito. There is one predatory species with a specialisation on blood-fed mosquitoes including An. gambiae s.l.. Evarcha culicivora is a jumping spider, known as the vampire spider, found around Lake Victoria. There is no evidence that these salticids require Anopheles mosquitoes and will readily consume blood-fed Culex. Interspecific competition studies focus on other mosquitoes of larval habitats. Many of these take place in artificial cosms and give contrasting results to semi-field studies. This may limit their extrapolation regarding the potential impact of reduced An. gambiae numbers. Previous mosquito control interventions are informative and identify competitive release and niche opportunism; so while the identity and relative abundance of the species present may change, the biomass available to predators may not.
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Affiliation(s)
- C. M. Collins
- Centre for Environmental PolicyImperial College LondonLondonU.K.
| | - J. A. S. Bonds
- Bonds Consulting Group LLCPanama City Beach, FloridaU.S.A.
| | - M. M. Quinlan
- Centre for Environmental PolicyImperial College LondonLondonU.K.
| | - J. D. Mumford
- Centre for Environmental PolicyImperial College LondonLondonU.K.
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116
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Habtewold T, Tapanelli S, Masters EKG, Hoermann A, Windbichler N, Christophides GK. Streamlined SMFA and mosquito dark-feeding regime significantly improve malaria transmission-blocking assay robustness and sensitivity. Malar J 2019; 18:24. [PMID: 30683107 PMCID: PMC6347765 DOI: 10.1186/s12936-019-2663-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 01/19/2019] [Indexed: 02/03/2023] Open
Abstract
Background The development of malaria transmission-blocking strategies including the generation of malaria refractory mosquitoes to replace the wild populations through means of gene drives hold great promise. The standard membrane feeding assay (SMFA) that involves mosquito feeding on parasitized blood through an artificial membrane system is a vital tool for evaluating the efficacy of transmission-blocking interventions. However, despite the availability of several published protocols, the SMFA remains highly variable and broadly insensitive. Methods The SMFA protocol was optimized through coordinated culturing of Anopheles coluzzii mosquitoes and Plasmodium falciparum parasite coupled with placing mosquitoes under a strict dark regime before, during, and after the gametocyte feed. Results A detailed description of essential steps is provided toward synchronized generation of highly fit An. coluzzii mosquitoes and P. falciparum gametocytes in preparation for an SMFA. A dark-infection regime that emulates the natural vector-parasite interaction system is described, which results in a significant increase in the infection intensity and prevalence. Using this optimal SMFA pipeline, a series of putative transmission-blocking antimicrobial peptides (AMPs) were screened, confirming that melittin and magainin can interfere with P. falciparum development in the vector. Conclusion A robust SMFA protocol that enhances the evaluation of interventions targeting human malaria transmission in laboratory setting is reported. Melittin and magainin are identified as highly potent antiparasitic AMPs that can be used for the generation of refractory Anopheles gambiae mosquitoes.
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Affiliation(s)
- Tibebu Habtewold
- Department of Life Sciences, Imperial College London, London, UK.
| | - Sofia Tapanelli
- Department of Life Sciences, Imperial College London, London, UK
| | | | - Astrid Hoermann
- Department of Life Sciences, Imperial College London, London, UK
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117
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Champer J, Chung J, Lee YL, Liu C, Yang E, Wen Z, Clark AG, Messer PW. Molecular safeguarding of CRISPR gene drive experiments. eLife 2019; 8:e41439. [PMID: 30666960 PMCID: PMC6358215 DOI: 10.7554/elife.41439] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2018] [Accepted: 01/09/2019] [Indexed: 12/20/2022] Open
Abstract
CRISPR-based homing gene drives have sparked both enthusiasm and deep concerns due to their potential for genetically altering entire species. This raises the question about our ability to prevent the unintended spread of such drives from the laboratory into a natural population. Here, we experimentally demonstrate the suitability of synthetic target site drives as well as split drives as flexible safeguarding strategies for gene drive experiments by showing that their performance closely resembles that of standard homing drives in Drosophila melanogaster. Using our split drive system, we further find that maternal deposition of both Cas9 and gRNA is required to form resistance alleles in the early embryo and that maternally-deposited Cas9 alone can power germline drive conversion in individuals that lack a genomic source of Cas9.
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Affiliation(s)
- Jackson Champer
- Department of Biological Statistics and Computational BiologyCornell UniversityIthacaUnited States
- Department of Molecular Biology and GeneticsCornell UniversityIthacaUnited States
| | - Joan Chung
- Department of Biological Statistics and Computational BiologyCornell UniversityIthacaUnited States
- Department of Molecular Biology and GeneticsCornell UniversityIthacaUnited States
| | - Yoo Lim Lee
- Department of Biological Statistics and Computational BiologyCornell UniversityIthacaUnited States
- Department of Molecular Biology and GeneticsCornell UniversityIthacaUnited States
| | - Chen Liu
- Department of Biological Statistics and Computational BiologyCornell UniversityIthacaUnited States
- Department of Molecular Biology and GeneticsCornell UniversityIthacaUnited States
| | - Emily Yang
- Department of Biological Statistics and Computational BiologyCornell UniversityIthacaUnited States
- Department of Molecular Biology and GeneticsCornell UniversityIthacaUnited States
| | - Zhaoxin Wen
- Department of Biological Statistics and Computational BiologyCornell UniversityIthacaUnited States
| | - Andrew G Clark
- Department of Biological Statistics and Computational BiologyCornell UniversityIthacaUnited States
| | - Philipp W Messer
- Department of Biological Statistics and Computational BiologyCornell UniversityIthacaUnited States
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118
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Wilder-Smith A, Chawla T, Ooi EE. Dengue: An Expanding Neglected Tropical Disease. NEGLECTED TROPICAL DISEASES - EAST ASIA 2019. [DOI: 10.1007/978-3-030-12008-5_4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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119
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Fouet C, Kamdem C. Integrated Mosquito Management: Is Precision Control a Luxury or Necessity? Trends Parasitol 2019; 35:85-95. [PMID: 30446394 PMCID: PMC6503858 DOI: 10.1016/j.pt.2018.10.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Revised: 10/16/2018] [Accepted: 10/18/2018] [Indexed: 12/23/2022]
Abstract
The versatility of mosquito species that spread emerging arthropod-borne viruses such as Zika has highlighted the urgent need to re-evaluate mosquito-control standards. The prospect of using precise knowledge of the geographic distribution and vector status of local populations to guide targeted interventions has gained renewed attention, but the feasibility and utility of such an approach remain to be investigated. Using the example of mosquito management in the USA, we present ideas for designing, monitoring, and assessing precision vector control tailored to different environmental and epidemiological settings. We emphasize the technical adjustments that could be implemented in mosquito-control districts to enable targeted control while strengthening traditional management.
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Affiliation(s)
- Caroline Fouet
- Department of Entomology, University of California, Riverside, CA 92521, USA
| | - Colince Kamdem
- Department of Entomology, University of California, Riverside, CA 92521, USA.
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120
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Abstract
Background Aedes aegypti is an important mosquito vector that transmits arboviruses that cause devastating diseases including Zika, dengue fever, yellow fever and chikungunya. Improved understanding of gene regulation in the early development of Ae. aegypti will facilitate genetic studies and help the development of novel control strategies of this important disease vector. Results In this study, we demonstrated through transgenic assays that the promoter of an endogenous early zygotic gene KLC2 could drive gene expression in the syncytial blastoderm and early cellular blastoderm, which is a stage that the developing germline and the rest of embryo are accessible to genetic manipulation. An unexpected expression of the reporter gene in transgenic male testes was also observed. Further analysis confirmed the expression of the endogenous KLC2 in the testes, which was not detected in the previous RNA sequencing data. Conclusions Our finding provided a new promoter element that can be used in future genetic studies and applications in Ae. aegypti. Moreover, our transgenic reporter assays showed that cautions are needed when interpreting RNA sequencing data as transient or tissue-specific transcription may go undetected by RNAseq. Electronic supplementary material The online version of this article (10.1186/s13071-018-3210-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Wanqi Hu
- Department of Biochemistry, Virginia Tech, 303 Fralin, Blacksburg, VA, 24061, USA.,Fralin Life Science Institute, Virginia Tech, Blacksburg, VA, 24061, USA
| | - Zhijian Jake Tu
- Department of Biochemistry, Virginia Tech, 303 Fralin, Blacksburg, VA, 24061, USA. .,Fralin Life Science Institute, Virginia Tech, Blacksburg, VA, 24061, USA.
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121
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Zacarés M, Salvador-Herranz G, Almenar D, Tur C, Argilés R, Bourtzis K, Bossin H, Pla I. Exploring the potential of computer vision analysis of pupae size dimorphism for adaptive sex sorting systems of various vector mosquito species. Parasit Vectors 2018; 11:656. [PMID: 30583722 PMCID: PMC6304766 DOI: 10.1186/s13071-018-3221-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Background Several mosquito population suppression strategies based on the rearing and release of sterile males have provided promising results. However, the lack of an efficient male selection method has hampered the expansion of these approaches into large-scale operational programmes. Currently, most of these programmes targeting Aedes mosquitoes rely on sorting methods based on the sexual size dimorphism (SSD) at the pupal stage. The currently available sorting methods have not been developed based on biometric analysis, and there is therefore potential for improvement. We applied an automated pupal size estimator developed by Grupo Tragsa with laboratory samples of Anopheles arabiensis, Aedes albopictus, Ae. polynesiensis, and three strains of Ae. aegypti. The frequency distribution of the pupal size was analyzed. We propose a general model for the analysis of the frequency distribution of mosquito pupae in the context of SSD-sorting methods, which is based on a Gaussian mixture distribution functions, thus making possible the analysis of performance (% males recovery) and purity (% males on the sorted sample). Results For the three Aedes species, the distribution of the pupae size can be modeled by a mixture of two Gaussian distribution functions and the proposed model fitted the experimental data. For a given population, each size threshold is linked to a specific outcome of male recovery. Two dimensionless parameters that measure the suitability for SSD-based sorting of a specific batch of pupae are provided. The optimal sorting results are predicted for the highest values of SSD and lowest values of intra-batch variance. Rearing conditions have a strong influence in the performance of the SSD-sorting methods and non-standard rearing can lead to increase pupae size heterogeneity. Conclusions Sex sorting of pupae based on size dimorphism can be achieved with a high performance (% males recovery) and a reasonably high purity (% males on the sorted sample) for the different Aedes species and strains. The purity and performance of a sex sorting operation in the tested Aedes species are linked parameters whose relation can be modeled. The conclusions of this analysis are applicable to all the existing SSD-sorting methods. The efficiency of the SSD-sorting methods can be improved by reducing the heterogeneity of pupae size within rearing containers. The heterogeneity between batches does not strongly affect the quality of the sex sorting, as long as a specific separation threshold is not pre-set before the sorting process. For new developments, we recommend using adaptive and precise threshold selection methods applied individually to each batch or to a mix of batches. Adaptive and precise thresholds will allow the sex-sorting of mixed batches in operational conditions maintaining the target purity at the cost of a reduction in performance. We also recommend a strategy whereby an acceptable level of purity is pre-selected and remains constant across the different batches of pupae while the performance varies from batch to batch to fit with the desired purity.
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Affiliation(s)
- Mario Zacarés
- Departamento de Ciencias Experimentales y Matemáticas, Universidad Católica de Valencia "San Vicente Mártir", C/Guillem de Castro 94, 46003, Valencia, Spain
| | - Gustavo Salvador-Herranz
- Departamento de Expresión Gráfica, Proyectos y Urbanismo, Universidad CEU Cardenal Herrera, Valencia, Spain
| | - David Almenar
- Grupo Tragsa, Avda. de la Industria 26, 46980, Paterna, Valencia, Spain
| | - Carles Tur
- Grupo Tragsa, Avda. de la Industria 26, 46980, Paterna, Valencia, Spain.
| | - Rafael Argilés
- Insect Pest Control Section, Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, Wagramerstrasse 5, PO Box 100, A-1400, Vienna, Austria
| | - Kostas Bourtzis
- Insect Pest Control Section, Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, Wagramerstrasse 5, PO Box 100, A-1400, Vienna, Austria
| | - Hervé Bossin
- Laboratoire d'Entomologie Médicale, Institut Louis Malardé, BP 30, 98713, Papeete, Tahiti, French Polynesia.,IRD, AP-HM, SSA, VITROME, IHU-Méditerranée infection, Univ. Aix Marseille, Marseille, France
| | - Ignacio Pla
- Grupo Tragsa, Avda. de la Industria 26, 46980, Paterna, Valencia, Spain
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122
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Matthews BJ, Dudchenko O, Kingan SB, Koren S, Antoshechkin I, Crawford JE, Glassford WJ, Herre M, Redmond SN, Rose NH, Weedall GD, Wu Y, Batra SS, Brito-Sierra CA, Buckingham SD, Campbell CL, Chan S, Cox E, Evans BR, Fansiri T, Filipović I, Fontaine A, Gloria-Soria A, Hall R, Joardar VS, Jones AK, Kay RGG, Kodali VK, Lee J, Lycett GJ, Mitchell SN, Muehling J, Murphy MR, Omer AD, Partridge FA, Peluso P, Aiden AP, Ramasamy V, Rašić G, Roy S, Saavedra-Rodriguez K, Sharan S, Sharma A, Smith ML, Turner J, Weakley AM, Zhao Z, Akbari OS, Black WC, Cao H, Darby AC, Hill CA, Johnston JS, Murphy TD, Raikhel AS, Sattelle DB, Sharakhov IV, White BJ, Zhao L, Aiden EL, Mann RS, Lambrechts L, Powell JR, Sharakhova MV, Tu Z, Robertson HM, McBride CS, Hastie AR, Korlach J, Neafsey DE, Phillippy AM, Vosshall LB. Improved reference genome of Aedes aegypti informs arbovirus vector control. Nature 2018; 563:501-507. [PMID: 30429615 PMCID: PMC6421076 DOI: 10.1038/s41586-018-0692-z] [Citation(s) in RCA: 315] [Impact Index Per Article: 52.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Accepted: 10/05/2018] [Indexed: 11/10/2022]
Abstract
Female Aedes aegypti mosquitoes infect more than 400 million people each year with dangerous viral pathogens including dengue, yellow fever, Zika and chikungunya. Progress in understanding the biology of mosquitoes and developing the tools to fight them has been slowed by the lack of a high-quality genome assembly. Here we combine diverse technologies to produce the markedly improved, fully re-annotated AaegL5 genome assembly, and demonstrate how it accelerates mosquito science. We anchored physical and cytogenetic maps, doubled the number of known chemosensory ionotropic receptors that guide mosquitoes to human hosts and egg-laying sites, provided further insight into the size and composition of the sex-determining M locus, and revealed copy-number variation among glutathione S-transferase genes that are important for insecticide resistance. Using high-resolution quantitative trait locus and population genomic analyses, we mapped new candidates for dengue vector competence and insecticide resistance. AaegL5 will catalyse new biological insights and intervention strategies to fight this deadly disease vector. An improved, fully re-annotated Aedes aegypti genome assembly (AaegL5) provides insights into the sex-determining M locus, chemosensory systems that help mosquitoes to hunt humans and loci involved in insecticide resistance and will help to generate intervention strategies to fight this deadly disease vector.
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Affiliation(s)
- Benjamin J Matthews
- Laboratory of Neurogenetics and Behavior, The Rockefeller University, New York, NY, USA. .,Howard Hughes Medical Institute, New York, NY, USA. .,Kavli Neural Systems Institute, New York, NY, USA.
| | - Olga Dudchenko
- The Center for Genome Architecture, Baylor College of Medicine, Houston, TX, USA.,Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA.,Department of Computer Science, Rice University, Houston, TX, USA.,Center for Theoretical and Biological Physics, Rice University, Houston, TX, USA
| | | | - Sergey Koren
- National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Igor Antoshechkin
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | | | - William J Glassford
- Mortimer B. Zuckerman Mind Brain Behavior Institute, Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA
| | - Margaret Herre
- Laboratory of Neurogenetics and Behavior, The Rockefeller University, New York, NY, USA.,Kavli Neural Systems Institute, New York, NY, USA
| | - Seth N Redmond
- Broad Institute of MIT and Harvard, Cambridge, MA, USA.,Department of Immunology and Infectious Disease, Harvard T. H. Chan School of Public Health, Boston, MA, USA
| | - Noah H Rose
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ, USA.,Princeton Neuroscience Institute, Princeton University, Princeton, NJ, USA
| | - Gareth D Weedall
- Vector Biology Department, Liverpool School of Tropical Medicine, Liverpool, UK.,Liverpool John Moores University, Liverpool, UK
| | - Yang Wu
- Department of Pathogen Biology, School of Public Health, Southern Medical University, Guangzhou, China.,Department of Biochemistry, Virginia Tech, Blacksburg, VA, USA.,Fralin Life Science Institute, Virginia Tech, Blacksburg, VA, USA
| | - Sanjit S Batra
- The Center for Genome Architecture, Baylor College of Medicine, Houston, TX, USA.,Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA.,Department of Computer Science, Rice University, Houston, TX, USA
| | - Carlos A Brito-Sierra
- Department of Entomology, Purdue University, West Lafayette, IN, USA.,Purdue Institute for Inflammation, Immunology and Infectious Disease, Purdue University, West Lafayette, IN, USA
| | - Steven D Buckingham
- Centre for Respiratory Biology, UCL Respiratory, University College London, London, UK
| | - Corey L Campbell
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Saki Chan
- Bionano Genomics, San Diego, CA, USA
| | - Eric Cox
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD, USA
| | - Benjamin R Evans
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT, USA
| | - Thanyalak Fansiri
- Vector Biology and Control Section, Department of Entomology, Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok, Thailand
| | - Igor Filipović
- Mosquito Control Laboratory, QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - Albin Fontaine
- Insect-Virus Interactions Group, Department of Genomes and Genetics, Institut Pasteur, Paris, France.,Unité de Parasitologie et Entomologie, Département des Maladies Infectieuses, Institut de Recherche Biomédicale des Armées, Marseille, France.,Centre National de la Recherche Scientifique, Unité Mixte de Recherche 2000, Paris, France.,Aix Marseille Université, IRD, AP-HM, SSA, UMR Vecteurs - Infections Tropicales et Méditerranéennes (VITROME), IHU - Méditerranée Infection, Marseille, France
| | - Andrea Gloria-Soria
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT, USA.,The Connecticut Agricultural Experiment Station, New Haven, CT, USA
| | | | - Vinita S Joardar
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD, USA
| | - Andrew K Jones
- Department of Biological and Medical Sciences, Faculty of Health and Life Sciences, Oxford Brookes University, Oxford, UK
| | - Raissa G G Kay
- Department of Entomology, University of California Riverside, Riverside, CA, USA
| | - Vamsi K Kodali
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD, USA
| | - Joyce Lee
- Bionano Genomics, San Diego, CA, USA
| | - Gareth J Lycett
- Vector Biology Department, Liverpool School of Tropical Medicine, Liverpool, UK
| | | | | | - Michael R Murphy
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD, USA
| | - Arina D Omer
- The Center for Genome Architecture, Baylor College of Medicine, Houston, TX, USA.,Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA.,Department of Computer Science, Rice University, Houston, TX, USA
| | - Frederick A Partridge
- Centre for Respiratory Biology, UCL Respiratory, University College London, London, UK
| | | | - Aviva Presser Aiden
- The Center for Genome Architecture, Baylor College of Medicine, Houston, TX, USA.,Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA.,Department of Bioengineering, Rice University, Houston, TX, USA.,Department of Pediatrics, Texas Children's Hospital, Houston, TX, USA
| | - Vidya Ramasamy
- Department of Biological and Medical Sciences, Faculty of Health and Life Sciences, Oxford Brookes University, Oxford, UK
| | - Gordana Rašić
- Mosquito Control Laboratory, QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - Sourav Roy
- Department of Entomology, Center for Disease Vector Research and Institute for Integrative Genome Biology, University of California, Riverside, CA, USA
| | - Karla Saavedra-Rodriguez
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Shruti Sharan
- Department of Entomology, Purdue University, West Lafayette, IN, USA.,Purdue Institute for Inflammation, Immunology and Infectious Disease, Purdue University, West Lafayette, IN, USA
| | - Atashi Sharma
- Fralin Life Science Institute, Virginia Tech, Blacksburg, VA, USA.,Department of Entomology, Virginia Tech, Blacksburg, VA, USA
| | | | - Joe Turner
- Institute of Integrative Biology, University of Liverpool, Liverpool, UK
| | | | - Zhilei Zhao
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ, USA.,Princeton Neuroscience Institute, Princeton University, Princeton, NJ, USA
| | - Omar S Akbari
- Division of Biological Sciences, University of California, San Diego, La Jolla, CA, USA.,Tata Institute for Genetics and Society, University of California, San Diego, La Jolla, CA, USA
| | - William C Black
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Han Cao
- Bionano Genomics, San Diego, CA, USA
| | - Alistair C Darby
- Institute of Integrative Biology, University of Liverpool, Liverpool, UK
| | - Catherine A Hill
- Department of Entomology, Purdue University, West Lafayette, IN, USA.,Purdue Institute for Inflammation, Immunology and Infectious Disease, Purdue University, West Lafayette, IN, USA
| | - J Spencer Johnston
- Department of Entomology, Texas A&M University, College Station, TX, USA
| | - Terence D Murphy
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD, USA
| | - Alexander S Raikhel
- Department of Entomology, Center for Disease Vector Research and Institute for Integrative Genome Biology, University of California, Riverside, CA, USA
| | - David B Sattelle
- Centre for Respiratory Biology, UCL Respiratory, University College London, London, UK
| | - Igor V Sharakhov
- Fralin Life Science Institute, Virginia Tech, Blacksburg, VA, USA.,Department of Entomology, Virginia Tech, Blacksburg, VA, USA.,Laboratory of Ecology, Genetics and Environmental Protection, Tomsk State University, Tomsk, Russia
| | | | - Li Zhao
- Laboratory of Evolutionary Genetics and Genomics, The Rockefeller University, New York, NY, USA
| | - Erez Lieberman Aiden
- The Center for Genome Architecture, Baylor College of Medicine, Houston, TX, USA.,Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA.,Department of Computer Science, Rice University, Houston, TX, USA.,Center for Theoretical and Biological Physics, Rice University, Houston, TX, USA.,Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Richard S Mann
- Mortimer B. Zuckerman Mind Brain Behavior Institute, Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA
| | - Louis Lambrechts
- Insect-Virus Interactions Group, Department of Genomes and Genetics, Institut Pasteur, Paris, France.,Centre National de la Recherche Scientifique, Unité Mixte de Recherche 2000, Paris, France
| | - Jeffrey R Powell
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT, USA
| | - Maria V Sharakhova
- Fralin Life Science Institute, Virginia Tech, Blacksburg, VA, USA.,Department of Entomology, Virginia Tech, Blacksburg, VA, USA.,Laboratory of Ecology, Genetics and Environmental Protection, Tomsk State University, Tomsk, Russia
| | - Zhijian Tu
- Department of Biochemistry, Virginia Tech, Blacksburg, VA, USA.,Fralin Life Science Institute, Virginia Tech, Blacksburg, VA, USA
| | - Hugh M Robertson
- Department of Entomology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Carolyn S McBride
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ, USA.,Princeton Neuroscience Institute, Princeton University, Princeton, NJ, USA
| | | | | | - Daniel E Neafsey
- Broad Institute of MIT and Harvard, Cambridge, MA, USA.,Department of Immunology and Infectious Disease, Harvard T. H. Chan School of Public Health, Boston, MA, USA
| | - Adam M Phillippy
- National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Leslie B Vosshall
- Laboratory of Neurogenetics and Behavior, The Rockefeller University, New York, NY, USA.,Howard Hughes Medical Institute, New York, NY, USA.,Kavli Neural Systems Institute, New York, NY, USA
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123
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Culbert NJ, Balestrino F, Dor A, Herranz GS, Yamada H, Wallner T, Bouyer J. A rapid quality control test to foster the development of genetic control in mosquitoes. Sci Rep 2018; 8:16179. [PMID: 30385841 PMCID: PMC6212531 DOI: 10.1038/s41598-018-34469-6] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2018] [Accepted: 10/10/2018] [Indexed: 01/10/2023] Open
Abstract
Vector-borne diseases are responsible for more than one million deaths per year. Alternative methods of mosquito control to insecticides such as genetic control techniques are thus urgently needed. In genetic techniques involving the release of sterile insects, it is critical to release insects of high quality. Sterile males must be able to disperse, survive and compete with wild males in order to inseminate wild females. There is currently no standardized, fast-processing method to assess mosquito male quality. Since male competitiveness is linked to their ability to fly, we developed a flight test device that aimed to measure the quality of sterile male mosquitoes via their capacity to escape a series of flight tubes within two hours and compared it to two other reference methods (survival rate and mating propensity). This comparison was achieved in three different stress treatment settings usually encountered when applying the sterile insect technique, i.e. irradiation, chilling and compaction. In all treatments, survival and insemination rates could be predicted by the results of a flight test, with over 80% of the inertia predicted. This novel tool could become a standardised quality control method to evaluate cumulative stress throughout the processes related to genetic control of mosquitoes.
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Affiliation(s)
- Nicole J Culbert
- Insect Pest Control Laboratory, Joint Food and Agriculture Organization of the United Nations/International Atomic Energy Agency Programme of Nuclear Techniques in Food and Agriculture, A-1400, Vienna, Austria
- Institute of Integrative Biology, Centre for Genomic Research, University of Liverpool, Liverpool, Merseyside, UK
| | - Fabrizio Balestrino
- Medical and Veterinary Entomology Department, Centro Agricoltura Ambiente CAA "G. Nicoli", Via Argini Nord 3351, 40014, Crevalcore, Italy
| | - Ariane Dor
- CONACYT-ECOSUR, Carretera Antiguo Aeropuerto km. 2.5, C.P. 30700, Tapachula, Chiapas, Mexico
| | - Gustavo S Herranz
- Technical School of Design, Architecture and Engineering, University CEU Cardenal Herrera, 46115, Calle San bartolomé 55 Alfara del Patriarca, Valencia, Spain
| | - Hanano Yamada
- Insect Pest Control Laboratory, Joint Food and Agriculture Organization of the United Nations/International Atomic Energy Agency Programme of Nuclear Techniques in Food and Agriculture, A-1400, Vienna, Austria
| | - Thomas Wallner
- Insect Pest Control Laboratory, Joint Food and Agriculture Organization of the United Nations/International Atomic Energy Agency Programme of Nuclear Techniques in Food and Agriculture, A-1400, Vienna, Austria
| | - Jérémy Bouyer
- Insect Pest Control Laboratory, Joint Food and Agriculture Organization of the United Nations/International Atomic Energy Agency Programme of Nuclear Techniques in Food and Agriculture, A-1400, Vienna, Austria.
- CIRAD, UMR ASTRE CIRAD-INRA ≪AnimalS, health, Territories, Risks and Ecosystems≫, Campus international de Baillarguet, 34398, Montpellier, France.
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124
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Turner J, Krishna R, Van't Hof AE, Sutton ER, Matzen K, Darby AC. The sequence of a male-specific genome region containing the sex determination switch in Aedes aegypti. Parasit Vectors 2018; 11:549. [PMID: 30342535 PMCID: PMC6195999 DOI: 10.1186/s13071-018-3090-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Accepted: 08/31/2018] [Indexed: 11/26/2022] Open
Abstract
Background Aedes aegypti is the principal vector of several important arboviruses. Among the methods of vector control to limit transmission of disease are genetic strategies that involve the release of sterile or genetically modified non-biting males, which has generated interest in manipulating mosquito sex ratios. Sex determination in Ae. aegypti is controlled by a non-recombining Y chromosome-like region called the M locus, yet characterisation of this locus has been thwarted by the repetitive nature of the genome. In 2015, an M locus gene named Nix was identified that displays the qualities of a sex determination switch. Results With the use of a whole-genome bacterial artificial chromosome (BAC) library, we amplified and sequenced a ~200 kb region containing the male-determining gene Nix. In this study, we show that Nix is comprised of two exons separated by a 99 kb intron primarily composed of repetitive DNA, especially transposable elements. Conclusions Nix, an unusually large and highly repetitive gene, exhibits features in common with Y chromosome genes in other organisms. We speculate that the lack of recombination at the M locus has allowed the expansion of repeats in a manner characteristic of a sex-limited chromosome, in accordance with proposed models of sex chromosome evolution in insects. Electronic supplementary material The online version of this article (10.1186/s13071-018-3090-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Joe Turner
- Centre for Genomic Research, Institute of Integrative Biology, University of Liverpool, Crown Street, Liverpool, L69 7ZB, UK.,Oxitec Ltd., 71 Innovation Drive, Milton Park, Abingdon, OX14 4RQ, UK
| | - Ritesh Krishna
- Centre for Genomic Research, Institute of Integrative Biology, University of Liverpool, Crown Street, Liverpool, L69 7ZB, UK.,IBM Research UK, STFC Daresbury Laboratory, Warrington, WA4 4AD, UK
| | - Arjen E Van't Hof
- Centre for Genomic Research, Institute of Integrative Biology, University of Liverpool, Crown Street, Liverpool, L69 7ZB, UK.,Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Elizabeth R Sutton
- Oxitec Ltd., 71 Innovation Drive, Milton Park, Abingdon, OX14 4RQ, UK.,Department of Zoology, University of Oxford, South Parks Road, Oxford, OX1 3PS, UK.,Sistemic, West of Scotland Science Park, Glasgow, G20 0SP, UK
| | - Kelly Matzen
- Oxitec Ltd., 71 Innovation Drive, Milton Park, Abingdon, OX14 4RQ, UK
| | - Alistair C Darby
- Centre for Genomic Research, Institute of Integrative Biology, University of Liverpool, Crown Street, Liverpool, L69 7ZB, UK.
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125
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Leftwich PT, Edgington MP, Harvey-Samuel T, Carabajal Paladino LZ, Norman VC, Alphey L. Recent advances in threshold-dependent gene drives for mosquitoes. Biochem Soc Trans 2018; 46:1203-1212. [PMID: 30190331 PMCID: PMC6195636 DOI: 10.1042/bst20180076] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Revised: 07/17/2018] [Accepted: 07/18/2018] [Indexed: 01/09/2023]
Abstract
Mosquito-borne diseases, such as malaria, dengue and chikungunya, cause morbidity and mortality around the world. Recent advances in gene drives have produced control methods that could theoretically modify all populations of a disease vector, from a single release, making whole species less able to transmit pathogens. This ability has caused both excitement, at the prospect of global eradication of mosquito-borne diseases, and concern around safeguards. Drive mechanisms that require individuals to be released at high frequency before genes will spread can therefore be desirable as they are potentially localised and reversible. These include underdominance-based strategies and use of the reproductive parasite Wolbachia Here, we review recent advances in practical applications and mathematical analyses of these threshold-dependent gene drives with a focus on implementation in Aedes aegypti, highlighting their mechanisms and the role of fitness costs on introduction frequencies. Drawing on the parallels between these systems offers useful insights into practical, controlled application of localised drives, and allows us to assess the requirements needed for gene drive reversal.
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Affiliation(s)
| | | | | | | | | | - Luke Alphey
- The Pirbright Institute, Pirbright, Woking, Surrey, U.K.
- Department of Zoology, University of Oxford, Oxford, U.K
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126
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Stakeholder attitudes towards the use of recombinant technology to manage the impact of an invasive species: Sea Lamprey in the North American Great Lakes. Biol Invasions 2018. [DOI: 10.1007/s10530-018-1848-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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127
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Shane JL, Grogan CL, Cwalina C, Lampe DJ. Blood meal-induced inhibition of vector-borne disease by transgenic microbiota. Nat Commun 2018; 9:4127. [PMID: 30297781 PMCID: PMC6175951 DOI: 10.1038/s41467-018-06580-9] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Accepted: 09/12/2018] [Indexed: 01/26/2023] Open
Abstract
Vector-borne diseases are a substantial portion of the global disease burden; one of the deadliest of these is malaria. Vector control strategies have been hindered by mosquito and pathogen resistances, and population alteration approaches using transgenic mosquitos still have many hurdles to overcome before they can be implemented in the field. Here we report a paratransgenic control strategy in which the microbiota of Anopheles stephensi was engineered to produce an antiplasmodial effector causing the mosquito to become refractory to Plasmodium berghei. The midgut symbiont Asaia was used to conditionally express the antiplasmodial protein scorpine only when a blood meal was present. These blood meal inducible Asaia strains significantly inhibit pathogen infection, and display improved fitness compared to strains that constitutively express the antiplasmodial effector. This strategy may allow the antiplasmodial bacterial strains to survive and be transmitted through mosquito populations, creating an easily implemented and enduring vector control strategy.
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Affiliation(s)
- Jackie L Shane
- Department of Biological Sciences, Duquesne University, 600 Forbes Avenue, Pittsburgh, PA, 15282, USA
| | - Christina L Grogan
- Department of Biological Sciences, Duquesne University, 600 Forbes Avenue, Pittsburgh, PA, 15282, USA
| | - Caroline Cwalina
- Department of Biological Sciences, Duquesne University, 600 Forbes Avenue, Pittsburgh, PA, 15282, USA
| | - David J Lampe
- Department of Biological Sciences, Duquesne University, 600 Forbes Avenue, Pittsburgh, PA, 15282, USA.
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128
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Abstract
"Conservation genomics" encompasses the idea that genome-scale data will improve the capacity of resource managers to protect species. Although genetic approaches have long been used in conservation research, it has only recently become tractable to generate genome-wide data at a scale that is useful for conservation. In this Review, we discuss how genome-scale data can inform species delineation in the face of admixture, facilitate evolution through the identification of adaptive alleles, and enhance evolutionary rescue based on genomic patterns of inbreeding. As genomic approaches become more widely adopted in conservation, we expect that they will have a positive impact on management and policy decisions.
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Affiliation(s)
- Megan A Supple
- Department of Ecology and Evolutionary Biology, University of California Santa Cruz, Santa Cruz, CA, 95060, USA.
| | - Beth Shapiro
- Department of Ecology and Evolutionary Biology, University of California Santa Cruz, Santa Cruz, CA, 95060, USA.
- UCSC Genomics Institute, University of California Santa Cruz, Santa Cruz, CA, 95060, USA.
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129
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Burford Reiskind MO, Labadie P, Bargielowski I, Lounibos LP, Reiskind MH. Rapid evolution and the genomic consequences of selection against interspecific mating. Mol Ecol 2018; 27:3641-3654. [DOI: 10.1111/mec.14821] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Revised: 06/28/2018] [Accepted: 07/10/2018] [Indexed: 01/10/2023]
Affiliation(s)
| | - Paul Labadie
- Department of Entomology and Plant Pathology; North Carolina State University; Raleigh North Carolina
| | - Irka Bargielowski
- Florida Medical Entomology Laboratory; University of Florida; Vero Beach Florida
| | - L. Philip Lounibos
- Florida Medical Entomology Laboratory; University of Florida; Vero Beach Florida
| | - Michael H. Reiskind
- Department of Entomology and Plant Pathology; North Carolina State University; Raleigh North Carolina
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130
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Morales-Hojas R, Hinsley M, Armean IM, Silk R, Harrup LE, Gonzalez-Uriarte A, Veronesi E, Campbell L, Nayduch D, Saski C, Tabachnick WJ, Kersey P, Carpenter S, Fife M. The genome of the biting midge Culicoides sonorensis and gene expression analyses of vector competence for bluetongue virus. BMC Genomics 2018; 19:624. [PMID: 30134833 PMCID: PMC6106943 DOI: 10.1186/s12864-018-5014-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Accepted: 08/14/2018] [Indexed: 01/25/2023] Open
Abstract
BACKGROUND The new genomic technologies have provided novel insights into the genetics of interactions between vectors, viruses and hosts, which are leading to advances in the control of arboviruses of medical importance. However, the development of tools and resources available for vectors of non-zoonotic arboviruses remains neglected. Biting midges of the genus Culicoides transmit some of the most important arboviruses of wildlife and livestock worldwide, with a global impact on economic productivity, health and welfare. The absence of a suitable reference genome has hindered genomic analyses to date in this important genus of vectors. In the present study, the genome of Culicoides sonorensis, a vector of bluetongue virus (BTV) in the USA, has been sequenced to provide the first reference genome for these vectors. In this study, we also report the use of the reference genome to perform initial transcriptomic analyses of vector competence for BTV. RESULTS Our analyses reveal that the genome is 189 Mb, assembled in 7974 scaffolds. Its annotation using the transcriptomic data generated in this study and in a previous study has identified 15,612 genes. Gene expression analyses of C. sonorensis females infected with BTV performed in this study revealed 165 genes that were differentially expressed between vector competent and refractory females. Two candidate genes, glutathione S-transferase (gst) and the antiviral helicase ski2, previously recognized as involved in vector competence for BTV in C. sonorensis (gst) and repressing dsRNA virus propagation (ski2), were confirmed in this study. CONCLUSIONS The reference genome of C. sonorensis has enabled preliminary analyses of the gene expression profiles of vector competent and refractory individuals. The genome and transcriptomes generated in this study provide suitable tools for future research on arbovirus transmission. These provide a valuable resource for these vector lineage, which diverged from other major Dipteran vector families over 200 million years ago. The genome will be a valuable source of comparative data for other important Dipteran vector families including mosquitoes (Culicidae) and sandflies (Psychodidae), and together with the transcriptomic data can yield potential targets for transgenic modification in vector control and functional studies.
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Affiliation(s)
- Ramiro Morales-Hojas
- The Pirbright Institute, Ash Road, Woking, Surrey, GU24 0NF, UK. .,Rothamsted Insect Survey, Rothamsted Research, West Common, Harpenden, Hertfordshire, AL5 2JQ, UK.
| | - Malcolm Hinsley
- EMBL-European Bioinformatics Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SD, UK
| | - Irina M Armean
- EMBL-European Bioinformatics Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SD, UK
| | - Rhiannon Silk
- The Pirbright Institute, Ash Road, Woking, Surrey, GU24 0NF, UK
| | - Lara E Harrup
- The Pirbright Institute, Ash Road, Woking, Surrey, GU24 0NF, UK
| | - Asier Gonzalez-Uriarte
- Bioinformatics group, Rothamsted Research, West Common, Harpenden, Hertfordshire, AL5 2JQ, UK
| | - Eva Veronesi
- The Pirbright Institute, Ash Road, Woking, Surrey, GU24 0NF, UK.,National Centre for Vector Entomology, Institute of Parasitology, Vetsuisse Faculty, University of Zürich, Zürich, Switzerland
| | - Lahcen Campbell
- EMBL-European Bioinformatics Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SD, UK
| | - Dana Nayduch
- USDA-ARS, Center for Grain and Animal Health Research, Arthropod Borne Animal Diseases Research Unit, 1515 College Avenue, Manhattan, KS, 66502, USA
| | - Christopher Saski
- Department of Genetics and Biochemistry, Clemson University Genomics Institute, BRC #310, 105 Collins Street, Clemson, SC, 29634, USA
| | - Walter J Tabachnick
- Florida Medical Entomology Laboratory, Department of Entomology and Nematology, University of Florida, IFAS, 200 9th St., SE, Vero Beach, FL, 32962, USA
| | - Paul Kersey
- EMBL-European Bioinformatics Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SD, UK
| | - Simon Carpenter
- The Pirbright Institute, Ash Road, Woking, Surrey, GU24 0NF, UK
| | - Mark Fife
- The Pirbright Institute, Ash Road, Woking, Surrey, GU24 0NF, UK
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131
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Famakinde DO. Treading the Path towards Genetic Control of Snail Resistance to Schistosome Infection. Trop Med Infect Dis 2018; 3:E86. [PMID: 30274482 PMCID: PMC6160955 DOI: 10.3390/tropicalmed3030086] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Revised: 08/08/2018] [Accepted: 08/13/2018] [Indexed: 01/05/2023] Open
Abstract
Schistosomiasis remains the most important tropical snail-borne trematodiasis that threatens many millions of human lives. In achieving schistosomiasis elimination targets, sustainable control of the snail vectors represents a logical approach. Nonetheless, the ineffectiveness of the present snail control interventions emphasizes the need to develop new complementary strategies to ensure more effective control outcomes. Accordingly, the use of genetic techniques aimed at driving resistance traits into natural vector populations has been put forward as a promising tool for integrated snail control. Leveraging the Biomphalaria-Schistosoma model system, studies unraveling the complexities of the vector biology and those exploring the molecular basis of snail resistance to schistosome infection have been expanding in various breadths, generating many significant discoveries, and raising the hope for future breakthroughs. This review provides a compendium of relevant findings, and without neglecting the current existing gaps and potential future challenges, discusses how a transgenic snail approach may be adapted and harnessed to control human schistosomiasis.
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Affiliation(s)
- Damilare O Famakinde
- Department of Medical Microbiology and Parasitology, College of Medicine, University of Lagos, Idi-Araba, Surulere, Lagos 100254, Nigeria.
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132
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Lebon C, Soupapoule K, Wilkinson DA, Le Goff G, Damiens D, Gouagna LC. Laboratory evaluation of the effects of sterilizing doses of γ-rays from Caesium-137 source on the daily flight activity and flight performance of Aedes albopictus males. PLoS One 2018; 13:e0202236. [PMID: 30107004 PMCID: PMC6091941 DOI: 10.1371/journal.pone.0202236] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Accepted: 07/30/2018] [Indexed: 12/17/2022] Open
Abstract
The control of Aedes albopictus through Sterile Male Releases requires that the most competitive males be mass-reared and sterilized usually with gamma- or X-ray radiation prior to release. Developing an understanding of the impact of irradiation treatment on flight performance in sterile males is very important because any fitness cost may reduce the efficacy of SIT intervention in the field. Here, we examined the role of irradiation exposure and sugar-feeding on daily flight activity and performance of Ae. albopictus males sterilized during pupal stage with gamma-radiation at 35Gray from a Caesium 137 source. We used a previously developed automated video tracking system to monitor the flight activity of different groups of sterile and control non-sterile males over 24 hours in a flight arena. This monitoring took place under controlled laboratory conditions and we wished to quantify the daily flight activity and to highlight any changes due to radiation treatment and nutritional conditions (starved versus sugar fed). Our experimental evidence demonstrated a characteristic diurnal flight activity with a bimodal pattern regardless of the treatment. Precisely, both irradiated and non-irradiated males exhibited two distinct peaks in flight activity in the morning (6-8 a.m.) and late afternoon (4-6 p.m.). Under changing physiological conditions, irradiated males were generally more active over time and flew longer overall distances than control male populations. These results suggest some internal circadian control of the phase relation to the light-dark cycle, with evidence for modification of flight performance by nutritional status. The fact that daily activity patterns are alike in irradiated and control Ae. albopictus males, and that sterile males could display higher flight performance, is in contrast with the hypothesis that irradiation treatment appears to reduce the fitness of male mosquitoes. We discuss the implications of the present study in sterile-male release programs against Ae. albopictus.
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Affiliation(s)
- Cyrille Lebon
- Institut de Recherche pour le Développement (IRD, Unité Mixte de Recherche « Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle » MIVEGEC (IRD 224-CNRS 5290-UM1-UM2), Montpellier, France
- IRD La Réunion / GIP CYROI (Recherche Santé Bio-innovation), Sainte-Clotilde, La Réunion Island, France
| | - Kevin Soupapoule
- Université de La Rochelle–UFR Sciences—Département de Biotechnologies, La Rochelle, France
| | - David A. Wilkinson
- Université de La Réunion, Unité Mixte de Recherche « Processus Infectieux en Milieu Insulaire Tropical (UMR PIMIT)», INSERM U1187-CNRS9192-IRD249. Plateforme de Recherche CYROI, Ste Clotilde, La Réunion Island, France
| | - Gilbert Le Goff
- Institut de Recherche pour le Développement (IRD, Unité Mixte de Recherche « Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle » MIVEGEC (IRD 224-CNRS 5290-UM1-UM2), Montpellier, France
- IRD La Réunion / GIP CYROI (Recherche Santé Bio-innovation), Sainte-Clotilde, La Réunion Island, France
| | - David Damiens
- Institut de Recherche pour le Développement (IRD, Unité Mixte de Recherche « Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle » MIVEGEC (IRD 224-CNRS 5290-UM1-UM2), Montpellier, France
- IRD La Réunion / GIP CYROI (Recherche Santé Bio-innovation), Sainte-Clotilde, La Réunion Island, France
| | - Louis Clément Gouagna
- Institut de Recherche pour le Développement (IRD, Unité Mixte de Recherche « Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle » MIVEGEC (IRD 224-CNRS 5290-UM1-UM2), Montpellier, France
- IRD La Réunion / GIP CYROI (Recherche Santé Bio-innovation), Sainte-Clotilde, La Réunion Island, France
- * E-mail:
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133
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Johnson BJ, Rohde BB, Zeak N, Staunton KM, Prachar T, Ritchie SA. A low-cost, battery-powered acoustic trap for surveilling male Aedes aegypti during rear-and-release operations. PLoS One 2018; 13:e0201709. [PMID: 30071091 PMCID: PMC6072092 DOI: 10.1371/journal.pone.0201709] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Accepted: 07/22/2018] [Indexed: 11/18/2022] Open
Abstract
The Aedes aegypti mosquito is a primary vector of several serious arboviruses throughout the world and is therefore of great concern to many public health organizations. With vector control methodology pivoting towards rearing and releasing large numbers of genetically modified, sterilized, or Wolbachia-infected male mosquitoes to control vector populations, economical surveillance methods for release tracking becomes increasingly necessary. Previous work has identified that male Ae. aegypti are attracted to female wingbeat frequencies and can be captured through artificial playback of these frequencies, but the tested systems are cost-prohibitive for wide-scale monitoring. Thus, we have developed a simple, low-cost, battery-powered, microcontroller-based sound lure which mimics the wingbeat frequency of female Ae. aegypti, thereby attracting males. We then tested the efficacy of this lure in combination with a passive (non-powered) gravid Aedes trap (GAT) against the current gold-standard, the Biogents Sentinel (BGS) trap, which requires main power (household power) and costs several times what the GAT does. Capture rates of male Ae. aegypti in sound-baited GATs (Sound-GATs) in these field tests were comparable to that of the BGS with no inhibitory effects of sound playback on female capture. We conclude that the Sound-GAT is an effective replacement of the costly BGS for surveillance of male Ae. aegypti mosquitoes, particularly in the developing countries where funding is limited, and has the potential to be adapted to target males of other medically important species.
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Affiliation(s)
- Brian J. Johnson
- College of Public Health, Medical and Veterinary Sciences, James Cook University, Cairns, Queensland, Australia
- Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, Queensland, Australia
| | - Barukh B. Rohde
- College of Public Health, Medical and Veterinary Sciences, James Cook University, Cairns, Queensland, Australia
- Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, Queensland, Australia
- Department of Electrical & Computer Engineering, University of Florida, Gainesville, Florida, United States of America
| | - Nicholas Zeak
- College of Public Health, Medical and Veterinary Sciences, James Cook University, Cairns, Queensland, Australia
- Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, Queensland, Australia
- Department of Electrical & Computer Engineering, University of Florida, Gainesville, Florida, United States of America
| | - Kyran M. Staunton
- College of Public Health, Medical and Veterinary Sciences, James Cook University, Cairns, Queensland, Australia
- Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, Queensland, Australia
| | - Tim Prachar
- Verily Life Sciences, South San Francisco, California, United States of America
| | - Scott A. Ritchie
- College of Public Health, Medical and Veterinary Sciences, James Cook University, Cairns, Queensland, Australia
- Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, Queensland, Australia
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134
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Burt A, Deredec A. Self-limiting population genetic control with sex-linked genome editors. Proc Biol Sci 2018; 285:rspb.2018.0776. [PMID: 30051868 PMCID: PMC6083257 DOI: 10.1098/rspb.2018.0776] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Accepted: 06/28/2018] [Indexed: 12/30/2022] Open
Abstract
In male heterogametic species the Y chromosome is transmitted solely from fathers to sons, and is selected for based only on its impacts on male fitness. This fact can be exploited to develop efficient pest control strategies that use Y-linked editors to disrupt the fitness of female descendants. With simple population genetic and dynamic models we show that Y-linked editors can be substantially more efficient than other self-limiting strategies and, while not as efficient as gene drive approaches, are expected to have less impact on non-target populations with which there is some gene flow. Efficiency can be further augmented by simultaneously releasing an autosomal X-shredder construct, in either the same or different males. Y-linked editors may be an attractive option to consider when efficient control of a species is desired in some locales but not others.
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Affiliation(s)
- Austin Burt
- Life Sciences, Imperial College, Silwood Park, Ascot SL5 7PY, UK
| | - Anne Deredec
- UMR BIOGER, INRA AgroParisTech, Université Paris-Saclay, Avenue Lucien Bretignières, 78850 Thiverval-Grignon, France
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135
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Strengthening regulatory capacity for gene drives in Africa: leveraging NEPAD's experience in establishing regulatory systems for medicines and GM crops in Africa. BMC Proc 2018; 12:11. [PMID: 30079102 PMCID: PMC6069767 DOI: 10.1186/s12919-018-0108-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
The New Partnership for Africa’s Development (NEPAD) Agency recognizes that Africa is in a period of transition and that this demands exploring and harnessing safe advances made in science-based innovations including modern biotechnology. To advance the science of biotechnology in Africa effectively, while at the same time safeguarding human health and the environment, the African Union (AU) adopted a High-Level Panel report on modern biotechnology entitled, Freedom to Innovate, which advocated for a coevolutionary approach where technology development goes hand in hand with regulation. Furthermore, most AU member states are Parties to the Cartagena Protocol on Biosafety (CPB), a legally binding international agreement negotiated, concluded and adopted within the framework of the Convention on Biological Diversity. This seeks to guide Parties in developing systems for the environmentally sound management of modern biotechnology applications. Currently, 49 AU Member States have signed and ratified the CPB, of which 12 have passed biosafety laws. African Union (AU) member states are at different stages in the development of regulatory frameworks for applications of modern biotechnology, which include genetically modified (GM) products and other emerging technologies. Biosafety regulatory frameworks comprise: biotechnology and/or biosafety policy; laws, regulations and guidelines; administrative systems; decision-making systems; and mechanisms for public engagement. To assist Member States to implement functional regulatory frameworks for both agriculture and health applications, the NEPAD Agency established the African Biosafety Network of Expertise (ABNE) and the African Medicines Regulatory Harmonization (AMRH). Currently, transgenic insects and GM crops are regulated by Competent National Authorities whose mandate derives from national biosafety laws. For GM crops, a lot of research has been conducted up to the confined field trial (CFT) and multi-location trials stages in a number of African countries. Burkina Faso has fully functional containment facilities for transgenic mosquitoes while Mali and Uganda are developing theirs. The Burkina Faso regulatory agency has granted permits and has already received sets of sterile mosquito eggs for trials in the contained facility. It is instructive to note that both ABNE and AMRH have worked with national and regional regulatory bodies in Africa to enhance their technical capacities for informed decision making, adoption of best practices, and compliance with international standards. It is against the backdrop of a rich blend of on-the-ground knowledge, experience, expertise, and insight into the context and political sensitivities of member states that the NEPAD Agency seeks to expand existing support. This would include capacity strengthening in the regulation of emerging technologies, such as the application of gene drives in the development of transgenic mosquito for the control of malaria transmission.
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136
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Dhole S, Vella MR, Lloyd AL, Gould F. Invasion and migration of spatially self-limiting gene drives: A comparative analysis. Evol Appl 2018; 11:794-808. [PMID: 29875820 PMCID: PMC5978947 DOI: 10.1111/eva.12583] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 11/27/2017] [Indexed: 12/14/2022] Open
Abstract
Recent advances in research on gene drives have produced genetic constructs that could theoretically spread a desired gene (payload) into all populations of a species, with a single release in one place. This attribute has advantages, but also comes with risks and ethical concerns. There has been a call for research on gene drive systems that are spatially and/or temporally self-limiting. Here, we use a population genetics model to compare the expected characteristics of three spatially self-limiting gene drive systems: one-locus underdominance, two-locus underdominance and daisy-chain drives. We find large differences between these gene drives in the minimum release size required for successfully driving a payload into a population. The daisy-chain system is the most efficient, requiring the smallest release, followed by the two-locus underdominance system, and then the one-locus underdominance system. However, when the target population exchanges migrants with a nontarget population, the gene drives requiring smaller releases suffer from higher risks of unintended spread. For payloads that incur relatively low fitness costs (up to 30%), a simple daisy-chain drive is practically incapable of remaining localized, even with migration rates as low as 0.5% per generation. The two-locus underdominance system can achieve localized spread under a broader range of migration rates and of payload fitness costs, while the one-locus underdominance system largely remains localized. We also find differences in the extent of population alteration and in the permanence of the alteration achieved by the three gene drives. The two-locus underdominance system does not always spread the payload to fixation, even after successful drive, while the daisy-chain system can, for a small set of parameter values, achieve a temporally limited spread of the payload. These differences could affect the suitability of each gene drive for specific applications.
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Affiliation(s)
- Sumit Dhole
- Department of Entomology and Plant PathologyNorth Carolina State UniversityRaleighNCUSA
| | - Michael R. Vella
- Genetic Engineering and Society CenterNorth Carolina State UniversityRaleighNCUSA
- Biomathematics Graduate ProgramDepartment of MathematicsNorth Carolina State UniversityRaleighNCUSA
| | - Alun L. Lloyd
- Genetic Engineering and Society CenterNorth Carolina State UniversityRaleighNCUSA
- Biomathematics Graduate ProgramDepartment of MathematicsNorth Carolina State UniversityRaleighNCUSA
| | - Fred Gould
- Department of Entomology and Plant PathologyNorth Carolina State UniversityRaleighNCUSA
- Genetic Engineering and Society CenterNorth Carolina State UniversityRaleighNCUSA
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137
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Champer J, Liu J, Oh SY, Reeves R, Luthra A, Oakes N, Clark AG, Messer PW. Reducing resistance allele formation in CRISPR gene drive. Proc Natl Acad Sci U S A 2018; 115:5522-5527. [PMID: 29735716 PMCID: PMC6003519 DOI: 10.1073/pnas.1720354115] [Citation(s) in RCA: 158] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
CRISPR homing gene drives can convert heterozygous cells with one copy of the drive allele into homozygotes, thereby enabling super-Mendelian inheritance. Such a mechanism could be used, for example, to rapidly disseminate a genetic payload in a population, promising effective strategies for the control of vector-borne diseases. However, all CRISPR homing gene drives studied in insects thus far have produced significant quantities of resistance alleles that would limit their spread. In this study, we provide an experimental demonstration that multiplexing of guide RNAs can both significantly increase the drive conversion efficiency and reduce germline resistance rates of a CRISPR homing gene drive in Drosophila melanogaster We further show that an autosomal drive can achieve drive conversion in the male germline, with no subsequent formation of resistance alleles in embryos through paternal carryover of Cas9. Finally, we find that the nanos promoter significantly lowers somatic Cas9 expression compared with the vasa promoter, suggesting that nanos provides a superior choice in drive strategies where gene disruption in somatic cells could have fitness costs. Comparison of drive parameters among the different constructs developed in this study and a previous study suggests that, while drive conversion and germline resistance rates are similar between different genomic targets, embryo resistance rates can vary significantly. Taken together, our results mark an important step toward developing effective gene drives capable of functioning in natural populations and provide several possible avenues for further control of resistance rates.
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Affiliation(s)
- Jackson Champer
- Department of Biological Statistics and Computational Biology, Cornell University, Ithaca, NY 14853;
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853
| | - Jingxian Liu
- Department of Biological Statistics and Computational Biology, Cornell University, Ithaca, NY 14853
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853
| | - Suh Yeon Oh
- Department of Biological Statistics and Computational Biology, Cornell University, Ithaca, NY 14853
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853
| | - Riona Reeves
- Department of Biological Statistics and Computational Biology, Cornell University, Ithaca, NY 14853
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853
| | - Anisha Luthra
- Department of Biological Statistics and Computational Biology, Cornell University, Ithaca, NY 14853
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853
| | - Nathan Oakes
- Department of Biological Statistics and Computational Biology, Cornell University, Ithaca, NY 14853
| | - Andrew G Clark
- Department of Biological Statistics and Computational Biology, Cornell University, Ithaca, NY 14853
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853
| | - Philipp W Messer
- Department of Biological Statistics and Computational Biology, Cornell University, Ithaca, NY 14853;
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138
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Alphey N, Bonsall MB. Genetics-based methods for agricultural insect pest management. AGRICULTURAL AND FOREST ENTOMOLOGY 2018; 20:131-140. [PMID: 29937693 PMCID: PMC5993313 DOI: 10.1111/afe.12241] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Revised: 04/10/2017] [Accepted: 05/21/2017] [Indexed: 06/01/2023]
Abstract
The sterile insect technique is an area-wide pest control method that reduces agricultural pest populations by releasing mass-reared sterile insects, which then compete for mates with wild insects. Contemporary genetics-based technologies use insects that are homozygous for a repressible dominant lethal genetic construct rather than being sterilized by irradiation.Engineered strains of agricultural pest species, including moths such as the diamondback moth Plutella xylostella and fruit flies such as the Mediterranean fruit fly Ceratitis capitata, have been developed with lethality that only operates on females.Transgenic crops expressing insecticidal toxins are widely used; the economic benefits of these crops would be lost if toxin resistance spread through the pest population. The primary resistance management method is a high-dose/refuge strategy, requiring toxin-free crops as refuges near the insecticidal crops, as well as toxin doses sufficiently high to kill wild-type insects and insects heterozygous for a resistance allele.Mass-release of toxin-sensitive engineered males (carrying female-lethal genes), as well as suppressing populations, could substantially delay or reverse the spread of resistance. These transgenic insect technologies could form an effective resistance management strategy.We outline some policy considerations for taking genetic insect control systems through to field implementation.
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Affiliation(s)
- Nina Alphey
- Mathematical Ecology Research Group, Department of Zoology, South Parks RoadOxford OX1 3PSU.K.
- Department of Life SciencesImperial College London, Silwood Park Campus, Buckhurst RoadAscot SL5 7PYU.K.
- The Pirbright Institute, Ash RoadPirbirght GU24 0NFU.K.
| | - Michael B. Bonsall
- Mathematical Ecology Research Group, Department of Zoology, South Parks RoadOxford OX1 3PSU.K.
- Department of Life SciencesImperial College London, Silwood Park Campus, Buckhurst RoadAscot SL5 7PYU.K.
- St Peter's College, New Inn Hall StreetOxford OX1 2DLU.K.
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139
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Edgington MP, Alphey LS. Population dynamics of engineered underdominance and killer-rescue gene drives in the control of disease vectors. PLoS Comput Biol 2018; 14:e1006059. [PMID: 29570717 PMCID: PMC5884568 DOI: 10.1371/journal.pcbi.1006059] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Revised: 04/04/2018] [Accepted: 02/27/2018] [Indexed: 12/12/2022] Open
Abstract
A number of different genetics-based vector control methods have been proposed. Two approaches currently under development in Aedes aegypti mosquitoes are the two-locus engineered underdominance and killer-rescue gene drive systems. Each of these is theoretically capable of increasing in frequency within a population, thus spreading associated desirable genetic traits. Thus they have gained attention for their potential to aid in the fight against various mosquito-vectored diseases. In the case of engineered underdominance, introduced transgenes are theoretically capable of persisting indefinitely (i.e. it is self-sustaining) whilst in the killer-rescue system the rescue component should initially increase in frequency (while the lethal component (killer) is common) before eventually declining (when the killer is rare) and being eliminated (i.e. it is temporally self-limiting). The population genetics of both systems have been explored using discrete generation mathematical models. The effects of various ecological factors on these two systems have also been considered using alternative modelling methodologies. Here we formulate and analyse new mathematical models combining the population dynamics and population genetics of these two classes of gene drive that incorporate ecological factors not previously studied and are simple enough to allow the effects of each to be disentangled. In particular, we focus on the potential effects that may be obtained as a result of differing ecological factors such as strengths of larval competition; numbers of breeding sites; and the relative fitness of transgenic mosquitoes compared with their wild-type counterparts. We also extend our models to consider population dynamics in two demes in order to explore the effects of dispersal between neighbouring populations on the outcome of UD and KR gene drive systems.
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Affiliation(s)
| | - Luke S. Alphey
- The Pirbright Institute, Pirbright, Woking, Surrey, United Kingdom
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140
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Famakinde DO. Mosquitoes and the Lymphatic Filarial Parasites: Research Trends and Budding Roadmaps to Future Disease Eradication. Trop Med Infect Dis 2018; 3:E4. [PMID: 30274403 PMCID: PMC6136629 DOI: 10.3390/tropicalmed3010004] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Revised: 12/26/2017] [Accepted: 12/27/2017] [Indexed: 11/17/2022] Open
Abstract
The mosquito-borne lymphatic filariasis (LF) is a parasitic, neglected tropical disease that imposes an unbearable human scourge. Despite the unprecedented efforts in mass drug administration (MDA) and morbidity management, achieving the global LF elimination slated for the year 2020 has been thwarted by limited MDA coverage and ineffectiveness in the chemotherapeutic intervention. Moreover, successful and sustainable elimination of mosquito-vectored diseases is often encumbered by reintroduction and resurgence emanating from human residual or new infections being widely disseminated by the vectors even when chemotherapy proves effective, but especially in the absence of effective vaccines. This created impetus for strengthening the current defective mosquito control approach, and profound research in vector⁻pathogen systems and vector biology has been pushing the boundaries of ideas towards developing refined vector-harnessed control strategies. Eventual implementation of these emerging concepts will offer a synergistic approach that will not only accelerate LF elimination, but also augurs well for its future eradication. This brief review focuses on advances in mosquito⁻filaria research and considers the emerging prospects for future eradication of LF.
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Affiliation(s)
- Damilare O Famakinde
- Department of Medical Microbiology and Parasitology, College of Medicine of the University of Lagos, Idi-Araba, Lagos 100254, Nigeria.
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141
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Fouet C, Atkinson P, Kamdem C. Human Interventions: Driving Forces of Mosquito Evolution. Trends Parasitol 2018; 34:127-139. [PMID: 29301722 DOI: 10.1016/j.pt.2017.10.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Revised: 10/28/2017] [Accepted: 10/30/2017] [Indexed: 11/29/2022]
Abstract
One of the most common strategies for controlling mosquito-borne diseases relies on the use of chemical pesticides to repel or kill the mosquito vector. Pesticide exposure interferes with several key biological functions in the mosquito and triggers a variety of adaptive responses whose underlying mechanisms are only partially elucidated. The availability of reference genome sequences opens up the possibility of tracking signatures of evolutionary changes, including the most recent, across the genomes of many vector species. In this review, we highlight the recent genomic changes, which contribute to the fascinating adaptation of malaria vectors of the sub-Saharan African region to intensive insecticide-based interventions. We emphasize the operational significance of detailed genomic knowledge for current monitoring and decision-making.
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Affiliation(s)
- Caroline Fouet
- Department of Entomology, University of California, Riverside, CA 92521, USA
| | - Peter Atkinson
- Department of Entomology, University of California, Riverside, CA 92521, USA
| | - Colince Kamdem
- Department of Entomology, University of California, Riverside, CA 92521, USA.
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142
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Fessl B, Heimpel GE, Causton CE. Invasion of an Avian Nest Parasite, Philornis downsi, to the Galapagos Islands: Colonization History, Adaptations to Novel Ecosystems, and Conservation Challenges. DISEASE ECOLOGY 2018. [DOI: 10.1007/978-3-319-65909-1_9] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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143
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Mosquito-Borne Diseases: Prevention Is the Cure for Dengue, Chikungunya and Zika Viruses. PARASITOLOGY RESEARCH MONOGRAPHS 2018. [DOI: 10.1007/978-3-319-94075-5_11] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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144
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Abstract
The prospect of using genetic methods to target vector, parasite, and reservoir species offers tremendous potential benefits to public health, but the use of genome editing to alter the shared environment will require special attention to public perception and community governance in order to benefit the world. Public skepticism combined with the media scrutiny of gene drive systems could easily derail unpopular projects entirely, especially given the potential for trade barriers to be raised against countries that employ self-propagating gene drives. Hence, open and community-guided development of thoughtfully chosen applications is not only the most ethical approach, but also the most likely to overcome the economic, social, and diplomatic barriers. Here we review current and past attempts to alter ecosystems using biological methods, identify key determinants of social acceptance, and chart a stepwise path for developers towards safe and widely supported use.
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Affiliation(s)
- Devora A. Najjar
- Media Lab, Massachusetts Institute of Technology, Cambridge, MA, USA
| | | | | | - Kevin M. Esvelt
- Media Lab, Massachusetts Institute of Technology, Cambridge, MA, USA
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145
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Abstract
Self-propagating gene drive technologies have a number of desirable characteristics that warrant their development for the control of insect pest and vector populations, such as the malaria-transmitting mosquitoes. Theoretically easy to deploy and self-sustaining, these tools may be used to generate cost-effective interventions that benefit society without obvious bias related to wealth, age or education. Their species-specific design offers the potential to reduce environmental risks and aim to be compatible and complementary with other control strategies, potentially expediting the elimination and eradication of malaria. A number of strategies have been proposed for gene-drive based control of the malaria mosquito and recent demonstrations have shown proof-of-principle in the laboratory. Though several technical, ethical and regulatory challenges remain, none appear insurmountable if research continues in a step-wise and open manner.
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Affiliation(s)
| | - Roberto Galizi
- Department of Life Sciences, Imperial College London, London, UK
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146
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Ginsberg HS, Bargar TA, Hladik ML, Lubelczyk C. Management of Arthropod Pathogen Vectors in North America: Minimizing Adverse Effects on Pollinators. JOURNAL OF MEDICAL ENTOMOLOGY 2017; 54:1463-1475. [PMID: 28968680 DOI: 10.1093/jme/tjx146] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Indexed: 06/07/2023]
Abstract
Tick and mosquito management is important to public health protection. At the same time, growing concerns about declines of pollinator species raise the question of whether vector control practices might affect pollinator populations. We report the results of a task force of the North American Pollinator Protection Campaign (NAPPC) that examined potential effects of vector management practices on pollinators, and how these programs could be adjusted to minimize negative effects on pollinating species. The main types of vector control practices that might affect pollinators are landscape manipulation, biocontrol, and pesticide applications. Some current practices already minimize effects of vector control on pollinators (e.g., short-lived pesticides and application-targeting technologies). Nontarget effects can be further diminished by taking pollinator protection into account in the planning stages of vector management programs. Effects of vector control on pollinator species often depend on specific local conditions (e.g., proximity of locations with abundant vectors to concentrations of floral resources), so planning is most effective when it includes collaborations of local vector management professionals with local experts on pollinators. Interventions can then be designed to avoid pollinators (e.g., targeting applications to avoid blooming times and pollinator nesting habitats), while still optimizing public health protection. Research on efficient targeting of interventions, and on effects on pollinators of emerging technologies, will help mitigate potential deleterious effects on pollinators in future management programs. In particular, models that can predict effects of integrated pest management on vector-borne pathogen transmission, along with effects on pollinator populations, would be useful for collaborative decision-making.
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Affiliation(s)
- Howard S Ginsberg
- USGS Patuxent Wildlife Research Center, University of Rhode Island, RI Field Station, Woodward Hall - PSE, Kingston, RI 02881
| | - Timothy A Bargar
- USGS Wetland and Aquatic Research Center, 7920 NW 71st St., Gainesville, FL 32653
| | - Michelle L Hladik
- USGS California Water Science Center, 6000 J St., Placer Hall, Sacramento, CA 95819
| | - Charles Lubelczyk
- Maine Medical Center Research Institute, Vector-Borne Disease Laboratory, 81 Research Dr., Scarborough, ME 04074
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147
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Edgington MP, Alphey LS. Conditions for success of engineered underdominance gene drive systems. J Theor Biol 2017; 430:128-140. [PMID: 28728996 PMCID: PMC5562440 DOI: 10.1016/j.jtbi.2017.07.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Revised: 06/20/2017] [Accepted: 07/15/2017] [Indexed: 12/02/2022]
Abstract
Engineered underdominance is one of a number of different gene drive strategies that have been proposed for the genetic control of insect vectors of disease. Here we model a two-locus engineered underdominance based gene drive system that is based on the concept of mutually suppressing lethals. In such a system two genetic constructs are introduced, each possessing a lethal element and a suppressor of the lethal at the other locus. Specifically, we formulate and analyse a population genetics model of this system to assess when different combinations of release strategies (i.e. single or multiple releases of both sexes or males only) and genetic systems (i.e. bisex lethal or female-specific lethal elements and different strengths of suppressors) will give population replacement or fail to do so. We anticipate that results presented here will inform the future design of engineered underdominance gene drive systems as well as providing a point of reference regarding release strategies for those looking to test such a system. Our discussion is framed in the context of genetic control of insect vectors of disease. One of several serious threats in this context are Aedes aegypti mosquitoes as they are the primary vectors of dengue viruses. However, results are also applicable to Ae. aegypti as vectors of Zika, yellow fever and chikungunya viruses and also to the control of a number of other insect species and thereby of insect-vectored pathogens.
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Affiliation(s)
| | - Luke S Alphey
- The Pirbright Institute, Ash Road, Woking, Surrey, GU24 0NF, UK
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148
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Affiliation(s)
| | - Michael J. Wade
- Department of Biology; Indiana University; Bloomington IN USA
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149
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Bliman PA, Aronna MS, Coelho FC, da Silva MAHB. Ensuring successful introduction of Wolbachia in natural populations of Aedes aegypti by means of feedback control. J Math Biol 2017; 76:1269-1300. [DOI: 10.1007/s00285-017-1174-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Revised: 07/19/2017] [Indexed: 02/07/2023]
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150
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Hustedt J, Doum D, Keo V, Ly S, Sam B, Chan V, Alexander N, Bradley J, Prasetyo DB, Rachmat A, Muhammad S, Lopes S, Leang R, Hii J. Determining the efficacy of guppies and pyriproxyfen (Sumilarv® 2MR) combined with community engagement on dengue vectors in Cambodia: study protocol for a randomized controlled trial. Trials 2017; 18:367. [PMID: 28778174 PMCID: PMC5545006 DOI: 10.1186/s13063-017-2105-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Accepted: 07/14/2017] [Indexed: 11/16/2022] Open
Abstract
Background Evidence on the effectiveness of low-cost, sustainable, biological vector-control tools for the Aedes mosquitoes is limited. Therefore, the purpose of this trial is to estimate the impact of guppy fish (guppies), in combination with the use of the larvicide pyriproxyfen (Sumilarv® 2MR), and Communication for Behavioral Impact (COMBI) activities to reduce entomological indices in Cambodia. Methods/design In this cluster randomized controlled, superiority trial, 30 clusters comprising one or more villages each (with approximately 170 households) will be allocated, in a 1:1:1 ratio, to receive either (1) three interventions (guppies, Sumilarv® 2MR, and COMBI activities), (2) two interventions (guppies and COMBI activities), or (3) control (standard vector control). Households will be invited to participate, and entomology surveys among 40 randomly selected households per cluster will be carried out quarterly. The primary outcome will be the population density of adult female Aedes mosquitoes (i.e., number per house) trapped using adult resting collections. Secondary outcome measures will include the House Index, Container Index, Breteau Index, Pupae Per House, Pupae Per Person, mosquito infection rate, guppy fish coverage, Sumilarv® 2MR coverage, and percentage of respondents with knowledge about Aedes mosquitoes causing dengue. In the primary analysis, adult female Aedes density and mosquito infection rates will be aggregated over follow-up time points to give a single rate per cluster. This will be analyzed by negative binomial regression, yielding density ratios. Discussion This trial is expected to provide robust estimates of the intervention effect. A rigorous evaluation of these vector-control interventions is vital to developing an evidence-based dengue control strategy and to help direct government resources. Trial registration Current Controlled Trials, ID: ISRCTN85307778. Registered on 25 October 2015. Electronic supplementary material The online version of this article (doi:10.1186/s13063-017-2105-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- John Hustedt
- Malaria Consortium, House #91, St. 95, Boeung Trabek, Chamkar Morn, PO Box 2116, Phnom Penh, 12305, Cambodia. .,London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK.
| | - Dyna Doum
- Malaria Consortium, House #91, St. 95, Boeung Trabek, Chamkar Morn, PO Box 2116, Phnom Penh, 12305, Cambodia
| | - Vanney Keo
- Malaria Consortium, House #91, St. 95, Boeung Trabek, Chamkar Morn, PO Box 2116, Phnom Penh, 12305, Cambodia
| | - Sokha Ly
- Cambodian National Dengue Control Program, #477 Betong Street.(Corner St.92), Village Trapangsvay, Phnom Penh, Cambodia
| | - BunLeng Sam
- Cambodian National Dengue Control Program, #477 Betong Street.(Corner St.92), Village Trapangsvay, Phnom Penh, Cambodia
| | - Vibol Chan
- World Health Organization, No. 177-179 corner Streets Pasteur (51) and 254; Sankat Chak Tomouk Khan Daun Penh, Phnom Penh, Cambodia
| | - Neal Alexander
- London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - John Bradley
- London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Didot Budi Prasetyo
- US Naval Medical Research Unit-2, #2, St. 289, Boeung Kok 2 commune, Toul Kork district, 289 Samdach Penn Nouth, Phnom Penh, 1225, Cambodia
| | - Agus Rachmat
- US Naval Medical Research Unit-2, #2, St. 289, Boeung Kok 2 commune, Toul Kork district, 289 Samdach Penn Nouth, Phnom Penh, 1225, Cambodia
| | - Shafique Muhammad
- Malaria Consortium, House #91, St. 95, Boeung Trabek, Chamkar Morn, PO Box 2116, Phnom Penh, 12305, Cambodia
| | - Sergio Lopes
- Malaria Consortium, House #91, St. 95, Boeung Trabek, Chamkar Morn, PO Box 2116, Phnom Penh, 12305, Cambodia
| | - Rithea Leang
- Cambodian National Dengue Control Program, #477 Betong Street.(Corner St.92), Village Trapangsvay, Phnom Penh, Cambodia
| | - Jeffrey Hii
- Malaria Consortium, House #91, St. 95, Boeung Trabek, Chamkar Morn, PO Box 2116, Phnom Penh, 12305, Cambodia
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