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Somerville J, Zhou L, Raymond B. Aseptic Rearing and Infection with Gut Bacteria Improve the Fitness of Transgenic Diamondback Moth, Plutella xylostella. INSECTS 2019; 10:insects10040089. [PMID: 30925791 PMCID: PMC6523322 DOI: 10.3390/insects10040089] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Revised: 03/21/2019] [Accepted: 03/25/2019] [Indexed: 12/27/2022]
Abstract
Mass insect rearing can have a range of applications, for example in biological control of pests. The competitive fitness of released insects is extremely important in a number of applications. Here, we investigated how to improve the fitness of a transgenic diamondback moth, which has shown variation in mating ability when reared in different insectaries. Specifically we tested whether infection with a gut bacteria, Enterobacter cloacae, and aseptic rearing of larvae could improve insect growth and male performance. All larvae were readily infected with E. cloacae. Under aseptic rearing, pupal weights were reduced and there was a marginal reduction in larval survival. However, aseptic rearing substantially improved the fitness of transgenic males. In addition, under aseptic rearing, inoculation with E. cloacae increased pupal weights and male fitness, increasing the proportion of transgenic progeny from 20% to 30% relative to uninfected insects. Aseptic conditions may improve the fitness of transgenic males by excluding microbial contaminants, while symbiont inoculation could further improve fitness by providing additional protection against infection, or by normalizing insect physiology. The simple innovation of incorporating antibiotic into diet, and inoculating insects with symbiotic bacteria that are resistant to that antibiotic, could provide a readily transferable tool for other insect rearing systems.
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Affiliation(s)
- Jasmine Somerville
- Centre for Ecology and Conservation, Penryn campus, College of Life and Environmental Science, University of Exeter, TR10 9FE, UK.
| | - Liqin Zhou
- Centre for Ecology and Conservation, Penryn campus, College of Life and Environmental Science, University of Exeter, TR10 9FE, UK.
| | - Ben Raymond
- Centre for Ecology and Conservation, Penryn campus, College of Life and Environmental Science, University of Exeter, TR10 9FE, UK.
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Zheng ZZ, Sun X, Zhang B, Pu J, Jiang ZY, Li M, Fan YJ, Xu YZ. Alternative splicing regulation of doublesex gene by RNA-binding proteins in the silkworm Bombyx mori. RNA Biol 2019; 16:809-820. [PMID: 30836863 DOI: 10.1080/15476286.2019.1590177] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Doublesex is highly conserved and sex-specifically spliced in insect sex-determination pathways, and its alternative splicing (AS) is regulated by Transformer, an exonic splicing activator, in the model system of Drosophila melanogaster. However, due to the lack of a transformer gene, AS regulation of doublesex remains unclear in Lepidoptera, which contain the economically important silkworm Bombyx mori and thousands of agricultural pests. Here, we use yeast three-hybrid system to screen for RNA-binding proteins that recognize sex-specific exons 3 and 4 of silkworm doublesex (Bm-dsx); this approach identified BxRBP1/Lark binding to the exon 3, and BxRBP2/TBPH and BxRBP3/Aret binding to the exon 4. Investigation of tissues shows that BxRBP1 and BxRBP2 have no sex specificity, but BxRBP3 has - three of its four isoforms are expressed with a sex-bias. Using novel sex-specific silkworm cell lines, we find that BxRBP1 and BxRBP3 directly interact with each other, and cooperatively function as splicing repressors. Over-expression of BxRBP1 and BxRBP3 isoforms efficiently inhibits splicing of the exons 3 and 4 in the female-specific cells and generates the male-specific isoform of Bm-dsx. We also demonstrate that the sex-determination upstream gene Masc regulates alternatively transcribed BxRBP3 isoforms. Thus, we identify a new regulatory mechanism of doublesex AS in the silkworm, revealing an evolutionary divergence in insect sex-determination.
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Affiliation(s)
- Zeng-Zhang Zheng
- a Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Science , Institute of Plant Physiology and Ecology, Chinese Academy of Sciences , Shanghai , China
| | - Xia Sun
- b College of Life Technology , Jiangsu University of Science and Technology , Zhenjiang , China
| | - Bei Zhang
- a Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Science , Institute of Plant Physiology and Ecology, Chinese Academy of Sciences , Shanghai , China
| | - Jia Pu
- a Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Science , Institute of Plant Physiology and Ecology, Chinese Academy of Sciences , Shanghai , China
| | - Ze-Yu Jiang
- a Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Science , Institute of Plant Physiology and Ecology, Chinese Academy of Sciences , Shanghai , China
| | - Muwang Li
- b College of Life Technology , Jiangsu University of Science and Technology , Zhenjiang , China
| | - Yu-Jie Fan
- c College of Life Science , Wuhan University , Wuhan , China
| | - Yong-Zhen Xu
- c College of Life Science , Wuhan University , Wuhan , China
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53
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Meza JS, ul Haq I, Vreysen MJB, Bourtzis K, Kyritsis GA, Cáceres C. Comparison of classical and transgenic genetic sexing strains of Mediterranean fruit fly (Diptera: Tephritidae) for application of the sterile insect technique. PLoS One 2018; 13:e0208880. [PMID: 30550598 PMCID: PMC6294381 DOI: 10.1371/journal.pone.0208880] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 11/27/2018] [Indexed: 11/22/2022] Open
Abstract
The development of genetic sexing strains (GSSs) based on classical genetic approaches has revolutionized the application of the sterile insect technique (SIT) against the Mediterranean fruit fly Ceratitis capitata (Wiedemann) (Diptera: Tephritidae). The global use of Mediterranean fruit fly GSS for SIT applications as part of area-wide integrated pest management (AW-IPM) programmes is testimony to their effectiveness. During recent years, transgenic sexing strains (TSSs) have been developed through genetic engineering techniques offering the possibility to produce male-only progeny by introducing female embryonic lethal genes and to increase the efficacy to identify released sterile males by means of the expression of fluorescent transgene markers. Here, we present a comparative analysis of two Mediterranean fruit fly strains: the classical GSS VIENNA 8D53-/Toliman and the transgenic FSEL#32. The strains were compared for production efficiency and quality control indices under semi mass-rearing conditions, response to sterilizing irradiation doses, male mating performance in walk-in field cages, and production cost of male-only pupae. The results showed that, the FSEL #32 TSS had a similar fecundity but a higher production of male-only pupae than the VIENNA 8D53-/Toliman GSS. For some of the quality control parameters tested, such as pupal weight and survival under starvation conditions, the FSEL #32 TSS was inferior to the VIENNA 8D53-/Toliman GSS. Both the transgenic and the classical genetic sexing strains have shown acceptable and similar mating competitiveness when compared with wild males for mating with wild females. The cost production for both strains is similar but the FSEL#32 TSS may potentially be more cost effective at higher production levels. The results are discussed in the context of incorporating the transgenic strain for SIT application.
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Affiliation(s)
- José S. Meza
- Insect Pest Control Laboratory, Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, International Atomic Energy Agency, Vienna, Austria
- Programa Moscafrut, SAGARPA-IICA, Metapa de Domínguez, Chiapas, México
- * E-mail:
| | - Ihsan ul Haq
- Insect Pest Control Laboratory, Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, International Atomic Energy Agency, Vienna, Austria
- National Agricultural Research Centre, Islamabad, Pakistan
| | - Marc J. B. Vreysen
- Insect Pest Control Laboratory, Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, International Atomic Energy Agency, Vienna, Austria
| | - Kostas Bourtzis
- Insect Pest Control Laboratory, Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, International Atomic Energy Agency, Vienna, Austria
| | - Georgios A. Kyritsis
- Insect Pest Control Laboratory, Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, International Atomic Energy Agency, Vienna, Austria
| | - Carlos Cáceres
- Insect Pest Control Laboratory, Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, International Atomic Energy Agency, Vienna, Austria
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54
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Neve P. Gene drive systems: do they have a place in agricultural weed management? PEST MANAGEMENT SCIENCE 2018; 74:2671-2679. [PMID: 29999229 PMCID: PMC6282749 DOI: 10.1002/ps.5137] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 07/06/2018] [Accepted: 07/07/2018] [Indexed: 05/11/2023]
Abstract
There is a pressing need for novel control techniques in agricultural weed management. Direct genetic control of agricultural pests encompasses a range of techniques to introduce and spread novel, fitness-reducing genetic modifications through pest populations. Recently, the development of CRISPR-Cas9 gene editing has brought these approaches into sharper focus. Proof of concept for CRISPR-Cas9-based gene drives has been demonstrated for the control of disease-vectoring insects. This article considers whether and how gene drives may be applied in agricultural weed management, focusing on CRISPR-Cas9-based systems. Population-suppression drives might be employed to introduce and proliferate deleterious mutations that directly impact fitness and weediness, whereas population-sensitizing drives would seek to edit weed genomes so that populations are rendered more sensitive to subsequent management interventions. Technical challenges relating to plant transformation and gene editing in planta are considered, and the implementation of gene drives for timely and sustainable weed management is reviewed in the light of weed population biology. The technical, biological, practical and regulatory challenges remain significant. Modelling-based studies can inform how and if gene drives could be employed in weed populations. These studies are an essential first step towards determining the utility of gene drives for weed management. © 2018 The Author. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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Affiliation(s)
- Paul Neve
- Biointeractions & Crop Protection DepartmentRothamsted Research, West CommonHertfordshireUK
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55
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Aumann RA, Schetelig MF, Häcker I. Highly efficient genome editing by homology-directed repair using Cas9 protein in Ceratitis capitata. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2018; 101:85-93. [PMID: 30157456 DOI: 10.1016/j.ibmb.2018.08.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2018] [Revised: 08/21/2018] [Accepted: 08/24/2018] [Indexed: 06/08/2023]
Abstract
The Mediterranean fruit fly Ceratitis capitata is a highly polyphagous and invasive insect pest, causing enormous economic damage in horticultural systems. A successful and environment-friendly control strategy is the sterile insect technique (SIT) that reduces pest populations through infertile matings with mass-released, sterilized insects. However, the SIT is not readily applicable to each pest species. While transgenic approaches hold great promise to improve critical aspects of the SIT to transfer it to new species, they are suspect to strict or even prohibitive legislation regarding the release of genetically modified (GM) organisms. In contrast, specific mutations created via CRISPR-Cas genome editing are not regulated as GM in the US, and might thus allow creating optimal strains for SIT. Here, we describe highly efficient homology-directed repair genome editing in C. capitata by injecting pre-assembled CRISPR-Cas9 ribonucleoprotein complexes using different guide RNAs and a short single-stranded oligodeoxynucleotide donor to convert an enhanced green fluorescent protein in C. capitata into a blue fluorescent protein. Six out of seven fertile and individually backcrossed G0 individuals generated 57-90% knock-in rate within their total offspring and 70-96% knock-in rate within their phenotypically mutant offspring. Based on the achieved efficiency, this approach could also be used to introduce mutations which do not produce a screenable phenotype and identify positive mutants with a reasonable workload. Furthermore, CRISPR-Cas HDR would allow to recreate mutations formerly identified in classical mutagenesis screens and to transfer them to related species to establish new (SIT-like) pest control systems. Considering the potential that CRISPR-induced alterations in organisms could be classified as non-GM in additional countries, such new strains could potentially be used for pest control applications without the need to struggle with GMO directives.
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Affiliation(s)
- Roswitha A Aumann
- Justus-Liebig-University Gießen, Institute for Insect Biotechnology, Department of Insect Biotechnology in Plant Protection, Winchesterstr. 2, 35394 Gießen, Germany
| | - Marc F Schetelig
- Justus-Liebig-University Gießen, Institute for Insect Biotechnology, Department of Insect Biotechnology in Plant Protection, Winchesterstr. 2, 35394 Gießen, Germany; Fraunhofer Institute for Molecular Biology and Applied Ecology (IME), Division of Bioresources, Department of Insect Pest and Vector Control, 35394 Gießen, Germany.
| | - Irina Häcker
- Justus-Liebig-University Gießen, Institute for Insect Biotechnology, Department of Insect Biotechnology in Plant Protection, Winchesterstr. 2, 35394 Gießen, Germany; Fraunhofer Institute for Molecular Biology and Applied Ecology (IME), Division of Bioresources, Department of Insect Pest and Vector Control, 35394 Gießen, Germany
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56
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Khamis D, El Mouden C, Kura K, Bonsall MB. Ecological effects on underdominance threshold drives for vector control. J Theor Biol 2018; 456:1-15. [PMID: 30040965 DOI: 10.1016/j.jtbi.2018.07.024] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Revised: 07/17/2018] [Accepted: 07/19/2018] [Indexed: 01/05/2023]
Abstract
Underdominance gene drives are frequency-dependent drives that aim to spread a desired homozygote genotype within a population. When the desired homozygote is released above a threshold frequency, heterozygote fitness disadvantage acts to drive the desired trait to fixation. Underdominance drives have been proposed as a way to control vector-borne disease through population suppression and replacement in a spatially contained and reversible way-benefits that directly address potential safety concerns with gene drives. Here, ecological and epidemiological dynamics are coupled to a model of mosquito genetics to investigate theoretically the impact of different types of underdominance gene drive on disease prevalence. We model systems with two engineered alleles carried either on the same pair of chromosomes at the same locus or homozygously on different pairs at different loci, genetic lethality that affects both sexes or only females, and bi-sex or male-only releases. Further, the different genetic and ecological fitness costs that can arise from genetic modification and artificial rearing are investigated through their effect on the population threshold frequency that is required to trigger the drive mechanism. We show that male-only releases must be significantly larger than bi-sex releases to trigger the underdominance drive. In addition, we find that female-specific lethality averts a higher percentage of disease cases over a control period than does bi-sex lethality. Decreases in the genetic fitness of the engineered homozygotes can increase the underdominance threshold substantially, but we find that the mating success of transgenic mosquitoes with wild-type females (influenced by a lack of competitiveness or the evolution of behavioural resistance in the form of active female mate preference) and the longevity of artificially-reared mosquitoes are vitally important to the success chances of underdominance based gene drive control efforts.
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Affiliation(s)
- Doran Khamis
- Mathematical Ecology Research Group, Department of Zoology, University of Oxford, Oxford OX1 3PS, UK
| | - Claire El Mouden
- Mathematical Ecology Research Group, Department of Zoology, University of Oxford, Oxford OX1 3PS, UK
| | - Klodeta Kura
- Mathematical Ecology Research Group, Department of Zoology, University of Oxford, Oxford OX1 3PS, UK
| | - Michael B Bonsall
- Mathematical Ecology Research Group, Department of Zoology, University of Oxford, Oxford OX1 3PS, UK.
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57
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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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58
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Abstract
Technologies for controlling mosquito vectors based on genetic manipulation and the release of genetically modified mosquitoes (GMMs) are gaining ground. However, concrete epidemiological evidence of their effectiveness, sustainability, and impact on the environment and nontarget species is lacking; no reliable ecological evidence on the potential interactions among GMMs, target populations, and other mosquito species populations exists; and no GMM technology has yet been approved by the WHO Vector Control Advisory Group. Our opinion is that, although GMMs may be considered a promising control tool, more studies are needed to assess their true effectiveness, risks, and benefits. Overall, several lines of evidence must be provided before GMM-based control strategies can be used under the integrated vector management framework.
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Affiliation(s)
- André B B Wilke
- Department of Public Health Sciences, University of Miami Miller School of Medicine, Miami, FL, USA
| | - John C Beier
- Department of Public Health Sciences, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Giovanni Benelli
- Department of Agriculture, Food and Environment, University of Pisa, via del Borghetto 80, 56124 Pisa, Italy; The BioRobotics Institute, Sant'Anna School of Advanced Studies, viale Rinaldo Piaggio 34, 56025 Pontedera, Pisa, Italy.
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59
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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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60
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Marubbi T, Cassidy C, Miller E, Koukidou M, Martin-Rendon E, Warner S, Loni A, Beech C. Exposure to genetically engineered olive fly (Bactrocera oleae) has no negative impact on three non-target organisms. Sci Rep 2017; 7:11478. [PMID: 28904391 PMCID: PMC5597591 DOI: 10.1038/s41598-017-11908-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Accepted: 08/30/2017] [Indexed: 11/09/2022] Open
Abstract
Bactrocera oleae (Diptera: Tephritidae) remains a major pest of olive fruit production worldwide. Current pest management programs largely depend on chemical insecticides, resulting in high economic and environmental costs. Alternative pest control approaches are therefore highly desirable. We have created a conditional female-specific self-limiting strain of B. oleae (OX3097D-Bol) that could be applied for sustainable pest control. OX3097D-Bol olive fly carries a fluorescent marker (DsRed2) for identification and a self-limiting genetic trait that is repressed by tetracycline. In the absence of tetracycline, the tetracycline transactivator (tTAV) accumulates, resulting in female death at larvae and early pupal stages. The aim of this study was to evaluate the impact of genetically engineered OX3097D-Bol olive fly on three non-target organisms that either predate or parasitize olive flies, one from the guild of parasitoids (Psyttalia concolor) and two from the guild of predators (Pardosa spider species and the rove beetle Aleochara bilineata). No significant negative effect was observed on life history parameters, mortality and reproductive capacity of the non-target organisms studied. These results suggest that potential exposure to DsRed2 and tTAV gene products (e.g. mRNA and encoded proteins) would have a negligible impact on on-target organisms in the guilds or predators and parasitoids.
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Affiliation(s)
- Thea Marubbi
- Oxitec Ltd., 71 Innovation Drive, Abingdon, Oxfordshire, OX14 4RX, United Kingdom
| | - Clare Cassidy
- Oxitec Ltd., 71 Innovation Drive, Abingdon, Oxfordshire, OX14 4RX, United Kingdom.,Unilever, 3 St. James Rd, Kingston upon Thames, KT1 2BA, UK
| | - Esther Miller
- Oxitec Ltd., 71 Innovation Drive, Abingdon, Oxfordshire, OX14 4RX, United Kingdom
| | - Martha Koukidou
- Oxitec Ltd., 71 Innovation Drive, Abingdon, Oxfordshire, OX14 4RX, United Kingdom
| | - Enca Martin-Rendon
- Oxitec Ltd., 71 Innovation Drive, Abingdon, Oxfordshire, OX14 4RX, United Kingdom.
| | - Simon Warner
- Oxitec Ltd., 71 Innovation Drive, Abingdon, Oxfordshire, OX14 4RX, United Kingdom
| | - Augusto Loni
- Department of Agriculture, Food and Environment, University of Pisa, Via del Borghetto 80, 56124, Pisa, Italy
| | - Camilla Beech
- Oxitec Ltd., 71 Innovation Drive, Abingdon, Oxfordshire, OX14 4RX, United Kingdom.,Cambea Consulting Ltd., 10 Beech Court, Wokingham Road, Hurst, Berkshire, RG10 0RQ, UK
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61
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Meccariello A, Monti SM, Romanelli A, Colonna R, Primo P, Inghilterra MG, Del Corsano G, Ramaglia A, Iazzetti G, Chiarore A, Patti F, Heinze SD, Salvemini M, Lindsay H, Chiavacci E, Burger A, Robinson MD, Mosimann C, Bopp D, Saccone G. Highly efficient DNA-free gene disruption in the agricultural pest Ceratitis capitata by CRISPR-Cas9 ribonucleoprotein complexes. Sci Rep 2017; 7:10061. [PMID: 28855635 PMCID: PMC5577161 DOI: 10.1038/s41598-017-10347-5] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Accepted: 08/07/2017] [Indexed: 12/20/2022] Open
Abstract
The Mediterranean fruitfly Ceratitis capitata (medfly) is an invasive agricultural pest of high economic impact and has become an emerging model for developing new genetic control strategies as an alternative to insecticides. Here, we report the successful adaptation of CRISPR-Cas9-based gene disruption in the medfly by injecting in vitro pre-assembled, solubilized Cas9 ribonucleoprotein complexes (RNPs) loaded with gene-specific single guide RNAs (sgRNA) into early embryos. When targeting the eye pigmentation gene white eye (we), a high rate of somatic mosaicism in surviving G0 adults was observed. Germline transmission rate of mutated we alleles by G0 animals was on average above 52%, with individual cases achieving nearly 100%. We further recovered large deletions in the we gene when two sites were simultaneously targeted by two sgRNAs. CRISPR-Cas9 targeting of the Ceratitis ortholog of the Drosophila segmentation paired gene (Ccprd) caused segmental malformations in late embryos and in hatched larvae. Mutant phenotypes correlate with repair by non-homologous end-joining (NHEJ) lesions in the two targeted genes. This simple and highly effective Cas9 RNP-based gene editing to introduce mutations in C. capitata will significantly advance the design and development of new effective strategies for pest control management.
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Affiliation(s)
- Angela Meccariello
- Department of Biology, University of Naples "Federico II", 80126, Napoli, Italy
| | - Simona Maria Monti
- Institute of Biostructures and Bioimaging (IBB), CNR, 80134, Naples, Italy
| | - Alessandra Romanelli
- Department of Pharmacy, University of Naples "Federico II", 80134, Napoli, Italy
| | - Rita Colonna
- Department of Biology, University of Naples "Federico II", 80126, Napoli, Italy
| | - Pasquale Primo
- Department of Biology, University of Naples "Federico II", 80126, Napoli, Italy
| | | | | | - Antonio Ramaglia
- Department of Physics "E. Pancini", University of Naples "Federico II", 80126, Napoli, Italy
| | - Giovanni Iazzetti
- Department of Biology, University of Naples "Federico II", 80126, Napoli, Italy
| | - Antonia Chiarore
- Stazione Zoologica Anton Dohrn, Center Villa Dohrn for Benthic Ecology, Punta San Pietro, 80077, Ischia, Italy
| | - Francesco Patti
- Stazione Zoologica Anton Dohrn, Center Villa Dohrn for Benthic Ecology, Punta San Pietro, 80077, Ischia, Italy
| | - Svenia D Heinze
- Institute of Molecular Life Sciences, University of Zürich, Zürich, 8057, Switzerland
| | - Marco Salvemini
- Department of Biology, University of Naples "Federico II", 80126, Napoli, Italy
| | - Helen Lindsay
- Institute of Molecular Life Sciences, University of Zürich, Zürich, 8057, Switzerland
- SIB Swiss Institute of Bioinformatics, University of Zürich, Zürich, 8057, Switzerland
| | - Elena Chiavacci
- Institute of Molecular Life Sciences, University of Zürich, Zürich, 8057, Switzerland
| | - Alexa Burger
- Institute of Molecular Life Sciences, University of Zürich, Zürich, 8057, Switzerland
| | - Mark D Robinson
- Institute of Molecular Life Sciences, University of Zürich, Zürich, 8057, Switzerland
- SIB Swiss Institute of Bioinformatics, University of Zürich, Zürich, 8057, Switzerland
| | - Christian Mosimann
- Institute of Molecular Life Sciences, University of Zürich, Zürich, 8057, Switzerland
| | - Daniel Bopp
- Institute of Molecular Life Sciences, University of Zürich, Zürich, 8057, Switzerland
| | - Giuseppe Saccone
- Department of Biology, University of Naples "Federico II", 80126, Napoli, Italy.
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62
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Building early-larval sexing systems for genetic control of the Australian sheep blow fly Lucilia cuprina using two constitutive promoters. Sci Rep 2017; 7:2538. [PMID: 28566730 PMCID: PMC5451413 DOI: 10.1038/s41598-017-02763-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Accepted: 04/18/2017] [Indexed: 11/15/2022] Open
Abstract
Transgenic sexing strains (TSS) that carry conditional female lethal genes are advantageous for genetic control programs based on the sterile insect technique (SIT). It is desirable if females die early in development as larval diet is a major cost for mass production facilities. This can be achieved by using a gene promoter that is only active in embryos to drive expression of the tetracycline transactivator (tTA), the transcription factor commonly used in two-component TSS. While an embryo-specific promoter is ideal it may not be essential for assembling an effective TSS as tTA can be repressed by addition of tetracycline to the diet at larval and/or adult stages. Here we have investigated this idea by isolating and employing the promoters from the Lucilia spitting image and actin 5C genes to drive tTA expression in embryos and later stages. L. cuprina TSS with the tTA drivers and tTA-regulated tetO-Lshid effectors produced only females when raised on a limited tetracycline diet. The Lshid transgene contains a sex-specific intron and as a consequence only females produce LsHID protein. TSS females died at early larval stages, which makes the lines advantageous for an SIT program.
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63
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Sagri E, Koskinioti P, Gregoriou ME, Tsoumani KT, Bassiakos YC, Mathiopoulos KD. Housekeeping in Tephritid insects: the best gene choice for expression analyses in the medfly and the olive fly. Sci Rep 2017; 7:45634. [PMID: 28368031 PMCID: PMC5377319 DOI: 10.1038/srep45634] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Accepted: 03/01/2017] [Indexed: 02/07/2023] Open
Abstract
Real-time quantitative-PCR has been a priceless tool for gene expression analyses. The reaction, however, needs proper normalization with the use of housekeeping genes (HKGs), whose expression remains stable throughout the experimental conditions. Often, the combination of several genes is required for accurate normalization. Most importantly, there are no universal HKGs which can be used since their expression varies among different organisms, tissues or experimental conditions. In the present study, nine common HKGs (RPL19, tbp, ubx, GAPDH, α-TUB, β-TUB, 14-3-3zeta, RPE and actin3) are evaluated in thirteen different body parts, developmental stages and reproductive and olfactory tissues of two insects of agricultural importance, the medfly and the olive fly. Three software programs based on different algorithms were used (geNorm, NormFinder and BestKeeper) and gave different ranking of HKG stabilities. This confirms once again that the stability of common HKGs should not be taken for granted and demonstrates the caution that is needed in the choice of the appropriate HKGs. Finally, by estimating the average of a standard score of the stability values resulted by the three programs we were able to provide a useful consensus key for the choice of the best HKG combination in various tissues of the two insects.
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Affiliation(s)
- Efthimia Sagri
- Department of Biochemistry and Biotechnology, University of Thessaly, Larissa, Greece
| | - Panagiota Koskinioti
- Department of Biochemistry and Biotechnology, University of Thessaly, Larissa, Greece
| | - Maria-Eleni Gregoriou
- Department of Biochemistry and Biotechnology, University of Thessaly, Larissa, Greece
| | | | - Yiannis C Bassiakos
- Department of Economic Sciences, National and Kapodistrian University of Athens, Athens, 10559, Greece
| | - Kostas D Mathiopoulos
- Department of Biochemistry and Biotechnology, University of Thessaly, Larissa, Greece
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64
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Harvey-Samuel T, Ant T, Alphey L. Towards the genetic control of invasive species. Biol Invasions 2017; 19:1683-1703. [PMID: 28620268 PMCID: PMC5446844 DOI: 10.1007/s10530-017-1384-6] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Accepted: 02/11/2017] [Indexed: 11/13/2022]
Abstract
Invasive species remain one of the greatest threats to global biodiversity. Their control would be enhanced through the development of more effective and sustainable pest management strategies. Recently, a novel form of genetic pest management (GPM) has been developed in which the mating behaviour of insect pests is exploited to introduce genetically engineered DNA sequences into wild conspecific populations. These 'transgenes' work in one or more ways to reduce the damage caused by a particular pest, for example reducing its density, or its ability to vector disease. Although currently being developed for use against economically important insect pests, these technologies would be highly appropriate for application against invasive species that threaten biodiversity. Importantly, these technologies have begun to advance in scope beyond insects to vertebrates, which include some of the world's worst invasives. Here we review the current state of this rapidly progressing field and, using an established set of eradication criteria, discuss the characteristics which make GPM technologies suitable for application against invasive pests.
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65
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Liu H, Liu Q, Zhou X, Huang Y, Zhang Z. Genome Editing of Wnt-1, a Gene Associated with Segmentation, via CRISPR/Cas9 in the Pine Caterpillar Moth, Dendrolimus punctatus. Front Physiol 2017; 7:666. [PMID: 28111552 PMCID: PMC5216022 DOI: 10.3389/fphys.2016.00666] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2016] [Accepted: 12/19/2016] [Indexed: 01/11/2023] Open
Abstract
The pine caterpillar moth, Dendrolimus punctatus, is a devastating forest pest. Genetic manipulation of this insect pest is limited due to the lack of genomic and functional genomic toolsets. Recently, CRISPR/Cas9 technology has been demonstrated to be a promising approach to modify the genome. To investigate gene functions during the embryogenesis, we introduced CRISPR/Cas9 system in D. punctatus to precisely and effectively manipulate gene expressions inmutant embryos. Compared to controls, knocking out of DpWnt-1, a gene well known for its role in the early body planning, led to high embryonic mortality. Among these mutants, 32.9% of the embryos and larvae showed an abnormal development. DpWnt-1 mutants predominantly exhibited abnormal posterior segments. In addition, multiple phenotypes were observed, including the loss of limbs and the head deformation, suggesting that DpWnt-1 signaling pathway is necessary for anterior segmentation and appendage development. Overall, our results demonstrate that CRISPR/Cas9 system is feasible and efficient in inducing mutations at a specific locus in D. punctatus. This study not only lays the foundation for characterizing gene functions in a non-model species, but also facilitates the future development of pest control alternatives for a major defoliator.
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Affiliation(s)
- Huihui Liu
- Key Laboratory of Forest Protection, Research Institute of Forest Ecology, Environment and Protection, Chinese Academy of Forestry, State Forestry Administration Beijing, China
| | - Qun Liu
- Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences Shanghai, China
| | - Xuguo Zhou
- Department of Entomology, University of Kentucky Lexington, KY, USA
| | - Yongping Huang
- Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences Shanghai, China
| | - Zhen Zhang
- Key Laboratory of Forest Protection, Research Institute of Forest Ecology, Environment and Protection, Chinese Academy of Forestry, State Forestry Administration Beijing, China
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66
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Xu J, Zhan S, Chen S, Zeng B, Li Z, James AA, Tan A, Huang Y. Sexually dimorphic traits in the silkworm, Bombyx mori, are regulated by doublesex. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2017; 80:42-51. [PMID: 27867075 DOI: 10.1016/j.ibmb.2016.11.005] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Revised: 10/19/2016] [Accepted: 11/16/2016] [Indexed: 06/06/2023]
Abstract
The DM domain genes, doublesex (dsx) in insects, or their structural homologs, male abnormal 3 (mab-3) in nematodes and Dmrt1 (doublesex and mab-3-related transcription factor 1) in mammals, are downstream regulators of the sex determination pathway that control sexually dimorphic development. Despite the functional importance of dsx and its potential applications in sterile insect technologies (SITs), the mechanisms by which it controls sexually dimorphic traits and the subsequent developmental gene networks in insects are poorly understood. Phylogenetic analyses indicate that insect dsx genes have sex-specific alternative splicing isoforms, whereas other taxa do not. We exploited genome editing and transgenesis technologies to induce mutations in either the male-specific isoform (dsxM) or common region (dsxC) of dsx in the somatic tissues of the lepidopteran model insect Bombyx mori. Disruptions of gene function produced either male-specific sexually-dimorphic defects or intersexual phenotypes; these results differ from those observed in other insects, including Drosophila melanogaster. Our data provide insights into the divergence of the insect sex determination pathways related to the most conserved downstream component dsx.
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Affiliation(s)
- Jun Xu
- Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shuai Zhan
- Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | - Shuqing Chen
- Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Baosheng Zeng
- Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhiqian Li
- Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | - Anthony A James
- Department of Microbiology & Molecular Genetics and Molecular Biology & Biochemistry, University of California, Irvine, CA 92697-3900, United States.
| | - Anjiang Tan
- Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China.
| | - Yongping Huang
- Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China.
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67
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Luo Y, Zhao S, Li J, Li P, Yan R. Isolation and Molecular Characterization of the Transformer Gene From Bactrocera cucurbitae (Diptera: Tephritidae). JOURNAL OF INSECT SCIENCE (ONLINE) 2017; 17:3755290. [PMID: 28931159 PMCID: PMC5469387 DOI: 10.1093/jisesa/iex031] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Indexed: 05/13/2023]
Abstract
transformer (tra) is a switch gene of sex determination in many insects, particularly in Dipterans. However, the sex determination pathway in Bactrocera cucurbitae (Coquillett), a very destructive pest on earth, remains largely uncharacterized. In this study, we have isolated and characterized one female-specific and two male-specific transcripts of the tra gene (Bcutra) of B. cucurbitae. The genomic structure of Bcutra has been determined and the presence of multiple conserved Transformer (TRA)/TRA-2 binding sites in Bcutra has been found. BcuTRA is highly conservative with its homologues in other tephritid fruit flies. Gene expression analysis of Bcutra at different developmental stages demonstrates that the female transcript of Bcutra appears earlier than the male counterparts, indicating that the maternal TRA is inherited in eggs and might play a role in the regulation of TRA expression. The conservation of protein sequence and sex-specific splicing of Bcutra and its expression patterns during development suggest that Bcutra is probably the master gene of sex determination of B. cucurbitae. Isolation of Bcutra will facilitate the development of a genetic sexing strain for its biological control.
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Affiliation(s)
- Ya Luo
- Department of Plant Protection, Institute of Tropical Agriculture and Forestry, Hainan University, Haikou, Hainan Province, China (; ; ; ; )Corresponding author, e-mail: , and
| | - Santao Zhao
- Department of Plant Protection, Institute of Tropical Agriculture and Forestry, Hainan University, Haikou, Hainan Province, China (; ; ; ; )Corresponding author, e-mail: , and
| | - Jiahui Li
- Department of Plant Protection, Institute of Tropical Agriculture and Forestry, Hainan University, Haikou, Hainan Province, China (; ; ; ; )Corresponding author, e-mail: , and
| | - Peizheng Li
- Department of Plant Protection, Institute of Tropical Agriculture and Forestry, Hainan University, Haikou, Hainan Province, China (; ; ; ; )Corresponding author, e-mail: , and
| | - Rihui Yan
- Department of Plant Protection, Institute of Tropical Agriculture and Forestry, Hainan University, Haikou, Hainan Province, China (; ; ; ; )Corresponding author, e-mail: , and
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, Hainan University, Haikou, Hainan Province, China ()
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68
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Sutton ER, Yu Y, Shimeld SM, White-Cooper H, Alphey AL. Identification of genes for engineering the male germline of Aedes aegypti and Ceratitis capitata. BMC Genomics 2016; 17:948. [PMID: 27871244 PMCID: PMC5117610 DOI: 10.1186/s12864-016-3280-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Accepted: 11/09/2016] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND Synthetic biology approaches are promising new strategies for control of pest insects that transmit disease and cause agricultural damage. These strategies require characterised modular components that can direct appropriate expression of effector sequences, with components conserved across species being particularly useful. The goal of this study was to identify genes from which new potential components could be derived for manipulation of the male germline in two major pest species, the mosquito Aedes aegypti and the tephritid fruit fly Ceratitis capitata. RESULTS Using RNA-seq data from staged testis samples, we identified several candidate genes with testis-specific expression and suitable expression timing for use of their regulatory regions in synthetic control constructs. We also developed a novel computational pipeline to identify candidate genes with testis-specific splicing from this data; use of alternative splicing is another method for restricting expression in synthetic systems. Some of the genes identified display testis-specific expression or splicing that is conserved across species; these are particularly promising candidates for construct development. CONCLUSIONS In this study we have identified a set of genes with testis-specific expression or splicing. In addition to their interest from a basic biology perspective, these findings provide a basis from which to develop synthetic systems to control important pest insects via manipulation of the male germline.
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Affiliation(s)
- Elizabeth R Sutton
- Department of Zoology, University of Oxford, Oxford, OX1 3PS, UK.,Oxitec Ltd, Milton Park, Abingdon, OX14 4RX, UK.,Present address: Sistemic, West of Scotland Science Park, Glasgow, G20 0SP, UK
| | - Yachuan Yu
- School of Biosciences, Cardiff University, Cardiff, CF10 3AX, UK.,Present address: The Beatson Institute for Cancer Research, CRUK, Glasgow, G61 1BD, UK
| | | | | | - And Luke Alphey
- Department of Zoology, University of Oxford, Oxford, OX1 3PS, UK. .,Oxitec Ltd, Milton Park, Abingdon, OX14 4RX, UK. .,The Pirbright Institute, Pirbright, GU24 0NF, UK.
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69
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Resistance to genetic insect control: Modelling the effects of space. J Theor Biol 2016; 413:72-85. [PMID: 27816677 PMCID: PMC5177727 DOI: 10.1016/j.jtbi.2016.10.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Revised: 10/07/2016] [Accepted: 10/28/2016] [Indexed: 12/26/2022]
Abstract
Genetic insect control, such as self-limiting RIDL2 (Release of Insects Carrying a Dominant Lethal) technology, is a development of the sterile insect technique which is proposed to suppress wild populations of a number of major agricultural and public health insect pests. This is achieved by mass rearing and releasing male insects that are homozygous for a repressible dominant lethal genetic construct, which causes death in progeny when inherited. The released genetically engineered ('GE') insects compete for mates with wild individuals, resulting in population suppression. A previous study modelled the evolution of a hypothetical resistance to the lethal construct using a frequency-dependent population genetic and population dynamic approach. This found that proliferation of resistance is possible but can be diluted by the introgression of susceptible alleles from the released homozygous-susceptible GE males. We develop this approach within a spatial context by modelling the spread of a lethal construct and resistance trait, and the effect on population control, in a two deme metapopulation, with GE release in one deme. Results show that spatial effects can drive an increased or decreased evolution of resistance in both the target and non-target demes, depending on the effectiveness and associated costs of the resistant trait, and on the rate of dispersal. A recurrent theme is the potential for the non-target deme to act as a source of resistant or susceptible alleles for the target deme through dispersal. This can in turn have a major impact on the effectiveness of insect population control.
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70
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Papanicolaou A, Schetelig MF, Arensburger P, Atkinson PW, Benoit JB, Bourtzis K, Castañera P, Cavanaugh JP, Chao H, Childers C, Curril I, Dinh H, Doddapaneni H, Dolan A, Dugan S, Friedrich M, Gasperi G, Geib S, Georgakilas G, Gibbs RA, Giers SD, Gomulski LM, González-Guzmán M, Guillem-Amat A, Han Y, Hatzigeorgiou AG, Hernández-Crespo P, Hughes DST, Jones JW, Karagkouni D, Koskinioti P, Lee SL, Malacrida AR, Manni M, Mathiopoulos K, Meccariello A, Munoz-Torres M, Murali SC, Murphy TD, Muzny DM, Oberhofer G, Ortego F, Paraskevopoulou MD, Poelchau M, Qu J, Reczko M, Robertson HM, Rosendale AJ, Rosselot AE, Saccone G, Salvemini M, Savini G, Schreiner P, Scolari F, Siciliano P, Sim SB, Tsiamis G, Ureña E, Vlachos IS, Werren JH, Wimmer EA, Worley KC, Zacharopoulou A, Richards S, Handler AM. The whole genome sequence of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann), reveals insights into the biology and adaptive evolution of a highly invasive pest species. Genome Biol 2016; 17:192. [PMID: 27659211 PMCID: PMC5034548 DOI: 10.1186/s13059-016-1049-2] [Citation(s) in RCA: 101] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Accepted: 08/26/2016] [Indexed: 01/01/2023] Open
Abstract
Background The Mediterranean fruit fly (medfly), Ceratitis capitata, is a major destructive insect pest due to its broad host range, which includes hundreds of fruits and vegetables. It exhibits a unique ability to invade and adapt to ecological niches throughout tropical and subtropical regions of the world, though medfly infestations have been prevented and controlled by the sterile insect technique (SIT) as part of integrated pest management programs (IPMs). The genetic analysis and manipulation of medfly has been subject to intensive study in an effort to improve SIT efficacy and other aspects of IPM control. Results The 479 Mb medfly genome is sequenced from adult flies from lines inbred for 20 generations. A high-quality assembly is achieved having a contig N50 of 45.7 kb and scaffold N50 of 4.06 Mb. In-depth curation of more than 1800 messenger RNAs shows specific gene expansions that can be related to invasiveness and host adaptation, including gene families for chemoreception, toxin and insecticide metabolism, cuticle proteins, opsins, and aquaporins. We identify genes relevant to IPM control, including those required to improve SIT. Conclusions The medfly genome sequence provides critical insights into the biology of one of the most serious and widespread agricultural pests. This knowledge should significantly advance the means of controlling the size and invasive potential of medfly populations. Its close relationship to Drosophila, and other insect species important to agriculture and human health, will further comparative functional and structural studies of insect genomes that should broaden our understanding of gene family evolution. Electronic supplementary material The online version of this article (doi:10.1186/s13059-016-1049-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Alexie Papanicolaou
- Hawkesbury Institute for the Environment, Western Sydney University, Sydney, Australia
| | - Marc F Schetelig
- Justus-Liebig-University Giessen, Institute for Insect Biotechnology, 35394, Giessen, Germany
| | - Peter Arensburger
- Department of Biological Sciences, Cal Poly Pomona, Pomona, CA, 91768, USA
| | - Peter W Atkinson
- Department of Entomology and Center for Disease Vector Research, University of California Riverside, Riverside, CA, 92521, USA.,Interdepartmental Graduate Program in Genetics, Genomics & Bioinformatics, University of California Riverside, Riverside, CA, 92521, USA
| | - Joshua B Benoit
- Department of Biological Sciences, University of Cincinnati, Cincinnati, OH, 45221, USA
| | - Kostas Bourtzis
- Insect Pest Control Laboratory, Joint FAO/IAEA Programme of Nuclear Techniques in Food and Agriculture, Seibersdorf, Vienna, Austria.,Department of Environmental and Natural Resources Management, University of Patras, Agrinio, Greece
| | - Pedro Castañera
- Department of Environmental Biology, Centro de Investigaciones Biológicas, CSIC, 28040, Madrid, Spain
| | - John P Cavanaugh
- Department of Biological Sciences, University of Cincinnati, Cincinnati, OH, 45221, USA
| | - Hsu Chao
- Human Genome Sequencing Center, Department of Human and Molecular Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | | | - Ingrid Curril
- Georg-August-Universität Göttingen, Johann-Friedrich-Blumenbach-Institut für Zoologie und Anthropologie, 37077, Göttingen, Germany
| | - Huyen Dinh
- Human Genome Sequencing Center, Department of Human and Molecular Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - HarshaVardhan Doddapaneni
- Human Genome Sequencing Center, Department of Human and Molecular Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Amanda Dolan
- Department of Biology, University of Rochester, Rochester, NY, 14627, USA
| | - Shannon Dugan
- Human Genome Sequencing Center, Department of Human and Molecular Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Markus Friedrich
- Department of Biological Sciences, Wayne State University, Detroit, MI, 48202, USA
| | - Giuliano Gasperi
- Department of Biology and Biotechnology, University of Pavia, 27100, Pavia, Italy
| | - Scott Geib
- USDA-ARS, Pacific Basin Agricultural Research Center, Hilo, HI, 96720, USA
| | - Georgios Georgakilas
- DIANA-Lab, Department of Electrical & Computer Engineering, University of Thessaly, 382 21 Volos, Greece and Hellenic Pasteur Institute, 11521, Athens, Greece
| | - Richard A Gibbs
- Human Genome Sequencing Center, Department of Human and Molecular Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Sarah D Giers
- Department of Entomology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Ludvik M Gomulski
- Department of Biology and Biotechnology, University of Pavia, 27100, Pavia, Italy
| | - Miguel González-Guzmán
- Department of Environmental Biology, Centro de Investigaciones Biológicas, CSIC, 28040, Madrid, Spain
| | - Ana Guillem-Amat
- Department of Environmental Biology, Centro de Investigaciones Biológicas, CSIC, 28040, Madrid, Spain
| | - Yi Han
- Human Genome Sequencing Center, Department of Human and Molecular Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Artemis G Hatzigeorgiou
- DIANA-Lab, Department of Electrical & Computer Engineering, University of Thessaly, 382 21 Volos, Greece and Hellenic Pasteur Institute, 11521, Athens, Greece
| | - Pedro Hernández-Crespo
- Department of Environmental Biology, Centro de Investigaciones Biológicas, CSIC, 28040, Madrid, Spain
| | - Daniel S T Hughes
- Human Genome Sequencing Center, Department of Human and Molecular Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Jeffery W Jones
- Department of Biological Sciences, Oakland University, Rochester, MI, 48309, USA
| | - Dimitra Karagkouni
- DIANA-Lab, Department of Electrical & Computer Engineering, University of Thessaly, 382 21 Volos, Greece and Hellenic Pasteur Institute, 11521, Athens, Greece
| | - Panagiota Koskinioti
- Department of Biochemistry and Biotechnology, University of Thessaly, Larissa, Greece
| | - Sandra L Lee
- Human Genome Sequencing Center, Department of Human and Molecular Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Anna R Malacrida
- Department of Biology and Biotechnology, University of Pavia, 27100, Pavia, Italy
| | - Mosè Manni
- Department of Biology and Biotechnology, University of Pavia, 27100, Pavia, Italy
| | - Kostas Mathiopoulos
- Department of Biochemistry and Biotechnology, University of Thessaly, Larissa, Greece
| | - Angela Meccariello
- Department of Biology, University of Naples Federico II, 80126, Naples, Italy
| | | | - Shwetha C Murali
- Human Genome Sequencing Center, Department of Human and Molecular Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Terence D Murphy
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Donna M Muzny
- Human Genome Sequencing Center, Department of Human and Molecular Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Georg Oberhofer
- Georg-August-Universität Göttingen, Johann-Friedrich-Blumenbach-Institut für Zoologie und Anthropologie, 37077, Göttingen, Germany
| | - Félix Ortego
- Department of Environmental Biology, Centro de Investigaciones Biológicas, CSIC, 28040, Madrid, Spain
| | - Maria D Paraskevopoulou
- DIANA-Lab, Department of Electrical & Computer Engineering, University of Thessaly, 382 21 Volos, Greece and Hellenic Pasteur Institute, 11521, Athens, Greece
| | - Monica Poelchau
- National Agricultural Library, USDA, Beltsville, MD, 20705, USA
| | - Jiaxin Qu
- Human Genome Sequencing Center, Department of Human and Molecular Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Martin Reczko
- Institute of Molecular Biology and Genetics, Biomedical Sciences Research Centre "Alexander Fleming", Vari, Greece
| | - Hugh M Robertson
- Department of Entomology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Andrew J Rosendale
- Department of Biological Sciences, University of Cincinnati, Cincinnati, OH, 45221, USA
| | - Andrew E Rosselot
- Department of Biological Sciences, University of Cincinnati, Cincinnati, OH, 45221, USA
| | - Giuseppe Saccone
- Department of Biology, University of Naples Federico II, 80126, Naples, Italy
| | - Marco Salvemini
- Department of Biology, University of Naples Federico II, 80126, Naples, Italy
| | - Grazia Savini
- Department of Biology and Biotechnology, University of Pavia, 27100, Pavia, Italy
| | - Patrick Schreiner
- Interdepartmental Graduate Program in Genetics, Genomics & Bioinformatics, University of California Riverside, Riverside, CA, 92521, USA
| | - Francesca Scolari
- Department of Biology and Biotechnology, University of Pavia, 27100, Pavia, Italy
| | - Paolo Siciliano
- Department of Biology and Biotechnology, University of Pavia, 27100, Pavia, Italy
| | - Sheina B Sim
- USDA-ARS, Pacific Basin Agricultural Research Center, Hilo, HI, 96720, USA
| | - George Tsiamis
- Department of Environmental and Natural Resources Management, University of Patras, Agrinio, Greece
| | - Enric Ureña
- Department of Environmental Biology, Centro de Investigaciones Biológicas, CSIC, 28040, Madrid, Spain
| | - Ioannis S Vlachos
- DIANA-Lab, Department of Electrical & Computer Engineering, University of Thessaly, 382 21 Volos, Greece and Hellenic Pasteur Institute, 11521, Athens, Greece
| | - John H Werren
- Department of Biology, University of Rochester, Rochester, NY, 14627, USA
| | - Ernst A Wimmer
- Georg-August-Universität Göttingen, Johann-Friedrich-Blumenbach-Institut für Zoologie und Anthropologie, 37077, Göttingen, Germany
| | - Kim C Worley
- Human Genome Sequencing Center, Department of Human and Molecular Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | | | - Stephen Richards
- Human Genome Sequencing Center, Department of Human and Molecular Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Alfred M Handler
- USDA-ARS, Center for Medical, Agricultural, and Veterinary Entomology, 1700 S.W. 23rd Drive, Gainesville, FL, 32608, USA.
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Criscione F, Qi Y, Tu Z. GUY1 confers complete female lethality and is a strong candidate for a male-determining factor in Anopheles stephensi. eLife 2016; 5. [PMID: 27644420 PMCID: PMC5061544 DOI: 10.7554/elife.19281] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Accepted: 09/12/2016] [Indexed: 12/02/2022] Open
Abstract
Despite their importance in sexual differentiation and reproduction, Y chromosome genes are rarely described because they reside in repeat-rich regions that are difficult to study. Here, we show that Guy1, a unique Y chromosome gene of a major urban malaria mosquito Anopheles stephensi, confers 100% female lethality when placed on the autosomes. We show that the small GUY1 protein (56 amino acids in length) causes female lethality and that males carrying the transgene are reproductively more competitive than their non-transgenic siblings under laboratory conditions. The GUY1 protein is a primary signal from the Y chromosome that affects embryonic development in a sex-specific manner. Our results have demonstrated, for the first time in mosquitoes, the feasibility of stable transgenic manipulation of sex ratios using an endogenous gene from the male-determining chromosome. These results provide insights into the elusive M factor and suggest exciting opportunities to reduce mosquito populations and disease transmission. DOI:http://dx.doi.org/10.7554/eLife.19281.001 Much like humans, Anopheles mosquitoes have a pair of sex chromosomes that determine whether they are male or female: females have two X chromosomes, while males have an X and a Y. Genetic evidence has indicated that there is a dominant male-determining factor on the Y chromosome that acts as a master switch to cause mosquitoes to develop into males. Mosquitoes that lack a Y chromosome, and hence the male-determining factor, therefore develop into the default female sex. Because only female mosquitoes feed on blood and transmit disease-causing microbes – including those that cause malaria – there is strong interest in identifying the male-determining factor. Introducing this gene into females could allow mosquito sex ratios to be manipulated towards the harmless non-biting males. In 2013, a study of male Anopheles stephensi mosquitoes identified a gene called Guy1 that is only found on the Y chromosome. Criscione et al. – who were involved in the 2013 study – now show that female A. stephensi mosquitoes die when the Guy1 gene is placed on their non-sex chromosomes. Further investigation confirmed that the protein produced from the Guy1 gene kills the females. This protein is an initiating signal that affects embryonic development in a sex-specific manner, making it a strong candidate to be the male determining factor in A. stephensi. This is consistent with previous reports in which the master switches of sex determination could be manipulated to kill specific sexes in fruit flies and nematode worms. Criscione et al. also found that males that carry the inserted Guy1 gene on their non-sex chromosomes – and so could potentially pass it on to both male and female offspring – are reproductively more competitive than their non-modified siblings under laboratory conditions. As the resulting female offspring would not survive, it is thus feasible, in principle, to genetically manipulate the sex ratio of the mosquitoes. A future challenge will be to identify how the protein encoded by the Guy1 gene acts to kill female mosquitoes. This knowledge will help to investigate the feasibility of using genetically modified mosquitoes to reduce Anopheles populations in order to control malaria. DOI:http://dx.doi.org/10.7554/eLife.19281.002
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Affiliation(s)
- Frank Criscione
- Department of Biochemistry, Virginia Tech, Blacksburg, United States
| | - Yumin Qi
- Department of Biochemistry, Virginia Tech, Blacksburg, United States
| | - Zhijian Tu
- Department of Biochemistry, Virginia Tech, Blacksburg, United States
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72
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Alphey L. SIT 2.0: 21(st) Century genetic technology for the screwworm sterile-insect program. BMC Biol 2016; 14:80. [PMID: 27643991 PMCID: PMC5029077 DOI: 10.1186/s12915-016-0310-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Accepted: 09/13/2016] [Indexed: 11/25/2022] Open
Abstract
Release of sterile insects, the Sterile Insect Technique (SIT), can be an extremely effective and precise method of pest control. A study in BMC Biology from the New World screwworm SIT program and others shows that modern genetic methods can provide major improvements even to this well-established and highly successful SIT program. See research article: https://bmcbiol.biomedcentral.com/articles/10.1186/s12915-016-0296-8
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Affiliation(s)
- Luke Alphey
- The Pirbright Institute, Ash Road, Woking, Surrey, GU24 0NF, UK.
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73
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Concha C, Palavesam A, Guerrero FD, Sagel A, Li F, Osborne JA, Hernandez Y, Pardo T, Quintero G, Vasquez M, Keller GP, Phillips PL, Welch JB, McMillan WO, Skoda SR, Scott MJ. A transgenic male-only strain of the New World screwworm for an improved control program using the sterile insect technique. BMC Biol 2016; 14:72. [PMID: 27576512 PMCID: PMC5004303 DOI: 10.1186/s12915-016-0296-8] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Accepted: 08/10/2016] [Indexed: 11/17/2022] Open
Abstract
Background The New World screwworm, Cochliomyia hominivorax, is a devastating pest of livestock endemic to subtropical and tropical regions of the Western hemisphere. The larvae of this species feed on the tissue of living animals, including man, and can cause death if untreated. Over 60 years ago, the sterile insect technique (SIT) was developed with the aim of eradicating this pest, initially from Florida but subsequently from all of North and Central America. From the outset it was appreciated that SIT would be more efficient if only sterile males were released in the field, but this was not possible until now. Results Here, we report on the development and evaluation of the first sexing strains of C. hominivorax that produce only males when raised on diet without tetracycline. Transgenic lines have been developed that possess a tetracycline repressible female-lethal genetic system. Ten of these lines show high female lethality at the late larval/pupal stages and three of them present dominant female lethality. Most of the lines were comparable to the wild type parental strain in several fitness parameters that are relevant to mass rearing in a production facility. Further, three lines performed well in male mating success and male competition assays, suggesting they would be sexually competitive in the field. Consequently, one transgenic line has been selected by the New World Screwworm Program for evaluation under mass rearing conditions. Conclusions We conclude that the promising characteristics of the selected sexing strains may contribute to reduce production costs for the existing eradication program and provide more efficient population suppression, which should make a genetic control program more economical in regions were C. hominivorax remains endemic. Electronic supplementary material The online version of this article (doi:10.1186/s12915-016-0296-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Carolina Concha
- Department of Entomology, North Carolina State University, Campus Box 7613, Raleigh, NC, 27695-7613, USA.,Panama-United States Commission for the Eradication and Prevention of Screwworm (COPEG), Pacora, Panama.,Smithsonian Tropical Research Institute, Naos Molecular Laboratory, Panama City, Panama
| | - Azhahianambi Palavesam
- USDA-ARS, Tick and Biting Fly Research Unit, Knipling-Bushland Livestock Insects Research Laboratory, 2700 Fredericksburg Rd., Kerrville, TX, 78028, USA.,Present address: Department of Veterinary Parasitology, Madras Veterinary College, Tamil Nadu Veterinary and Animal Sciences University, Chennai, India
| | - Felix D Guerrero
- USDA-ARS, Tick and Biting Fly Research Unit, Knipling-Bushland Livestock Insects Research Laboratory, 2700 Fredericksburg Rd., Kerrville, TX, 78028, USA
| | | | - Fang Li
- Department of Entomology, North Carolina State University, Campus Box 7613, Raleigh, NC, 27695-7613, USA
| | - Jason A Osborne
- Department of Statistics, North Carolina State University, Campus Box 8203, Raleigh, NC, 27695-8203, USA
| | - Yillian Hernandez
- Panama-United States Commission for the Eradication and Prevention of Screwworm (COPEG), Pacora, Panama
| | | | | | | | | | - Pamela L Phillips
- USDA-ARS, Screwworm Research Unit, Pacora, Panama.,USDA-ARS, Screwworm Research Unit, Knipling-Bushland Livestock Insects Research Laboratory, 2700 Fredericksburg Rd., Kerrville, TX, 78028, USA
| | - John B Welch
- USDA-APHIS, IS Action Programs, 2881 F&B Road, College Station, TX, 77845, USA
| | - W Owen McMillan
- Smithsonian Tropical Research Institute, Naos Molecular Laboratory, Panama City, Panama
| | - Steven R Skoda
- USDA-ARS, Screwworm Research Unit, Pacora, Panama.,USDA-ARS, Screwworm Research Unit, Knipling-Bushland Livestock Insects Research Laboratory, 2700 Fredericksburg Rd., Kerrville, TX, 78028, USA
| | - Maxwell J Scott
- Department of Entomology, North Carolina State University, Campus Box 7613, Raleigh, NC, 27695-7613, USA.
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Xu Q, Guerrero FD, Palavesam A, Pérez de León AA. Use of electroporation as an option to transform the horn fly, Haematobia irritans: a species recalcitrant to microinjection. INSECT SCIENCE 2016; 23:621-629. [PMID: 25645001 DOI: 10.1111/1744-7917.12207] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 01/13/2015] [Indexed: 06/04/2023]
Abstract
The horn fly, Haematobia irritans, is a serious pest of cattle in North America. The control of horn flies has primarily relied on insecticides. However, the heavy use of insecticides has led to the development of insecticide resistance in horn flies. Novel methods to control horn flies are greatly needed. Transgenic technology is an effective tool to genetically modify insects and may lead to novel methods of pest control based on genomic approaches. Here we report a piggyBac-mediated transformation of the horn fly via electroporation. Transformation with a DsRed fluorescent marker protein coding region was verified by PCR analysis of individual fly bodies and pupal cases and sequencing of PCR products. However, Southern blot analysis failed to indicate the DsRed gene was integrated into the horn fly genome. Thus, the electroporation protocol may have caused the DsRed gene to be integrated into bacterial symbionts of the horn fly.
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Affiliation(s)
- Qiang Xu
- Department of Biology, Abilene Christian University, Abilene, TX, 79699, USA
| | - Felix D Guerrero
- USDA-ARS Knipling-Bushland U.S. Livestock Insects Research Laboratory, 2700 Fredericksburg Rd., Kerrville, TX, 78028, USA
- USDA-ARS Veterinary Pest Genomics Center, Kerrville, TX, 78028, USA
| | - Azhahianambi Palavesam
- USDA-ARS Knipling-Bushland U.S. Livestock Insects Research Laboratory, 2700 Fredericksburg Rd., Kerrville, TX, 78028, USA
| | - Adalberto A Pérez de León
- USDA-ARS Knipling-Bushland U.S. Livestock Insects Research Laboratory, 2700 Fredericksburg Rd., Kerrville, TX, 78028, USA
- USDA-ARS Veterinary Pest Genomics Center, Kerrville, TX, 78028, USA
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75
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Schetelig MF, Targovska A, Meza JS, Bourtzis K, Handler AM. Tetracycline-suppressible female lethality and sterility in the Mexican fruit fly, Anastrepha ludens. INSECT MOLECULAR BIOLOGY 2016; 25:500-508. [PMID: 27135433 DOI: 10.1111/imb.12238] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The sterile insect technique (SIT) involves the mass release of sterile males to suppress insect pest populations. SIT has been improved for larval pests by the development of strains for female-specific tetracycline-suppressible (Tet-off) embryonic lethal systems for male-only populations. Here we describe the extension of this approach to the Mexican fruit fly, Anastrepha ludens, using a Tet-off driver construct with the Tet-transactivator (tTA) under embryo-specific Anastrepha suspensa serendipity α (As-sry-α) promoter regulation. In the absence of tetracycline, tTA acts upon a Tet-response element linked to the pro-apoptotic cell death gene lethal effector, head involuation defective (hid), from A. ludens (Alhid(Ala2) ) that contains a sex-specific intron splicing cassette, resulting in female-specific expression of the lethal effector. Parental adults double-homozygous for the driver/effector vectors were expected to yield male-only progeny when reared on Tet-free diet, but a complete lack of oviposited eggs resulted for each of the three strains tested. Ovary dissection revealed nonvitellogenic oocytes in all strains that was reversible by feeding females tetracycline for 5 days after eclosion, resulting in male-only adults in one strain. Presumably the sry-α promoter exhibits prezygotic maternal expression as well as zygotic embryonic expression in A. ludens, resulting in a Tet-off sterility effect in addition to female-specific lethality.
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Affiliation(s)
- M F Schetelig
- Justus-Liebig-University Giessen, Institute for Insect Biotechnology, Giessen, Germany
- USDA/ARS, Center for Medical, Agricultural and Veterinary Entomology, Gainesville, FL, USA
| | - A Targovska
- Insect Pest Control Laboratory, Joint FAO/IAEA Programme of Nuclear Techniques in Food and Agriculture, Vienna, Austria
| | - J S Meza
- Programa Moscafrut, SAGARPA-IICA, Metapa de Dominguez, Chiapas, Mexico
| | - K Bourtzis
- Insect Pest Control Laboratory, Joint FAO/IAEA Programme of Nuclear Techniques in Food and Agriculture, Vienna, Austria
| | - A M Handler
- USDA/ARS, Center for Medical, Agricultural and Veterinary Entomology, Gainesville, FL, USA
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Huang CY, Dai SM, Chang C. Introduction of the RTA-Bddsx gene induces female-specific lethal effects in transformed Bactrocera dorsalis (Hendel). PEST MANAGEMENT SCIENCE 2016; 72:1160-1167. [PMID: 26269247 DOI: 10.1002/ps.4094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Revised: 07/24/2015] [Accepted: 08/10/2015] [Indexed: 06/04/2023]
Abstract
BACKGROUND The oriental fruit fly, Bactrocera dorsalis (Hendel), can reduce fruit production and quality and is considered to be a major insect pest in many Asian countries. A system combining the toxicity of ricin and the alternative RNA splicing properties of doublesex (RTA-Bddsx) has been proposed that results in differential sexual processing in vitro. A transgenic approach was used in this study to confirm the existence of female-specific lethal effects in vivo. RESULTS The piggyBac-based vector PB-Acp-CF21-26, which carries the actin 5C promoter and RTA-Bddsx, was used to establish transgenic lines. Five surviving male flies (F1) demonstrated the presence of selection marker Ds-Red((+)) throughout their entire bodies following single-pair mating with wild-type females, indicating germline transmission. A high percentage of males (59.6-100%) were observed in transformed F3 offspring, and this skewed sex ratio indicated that the female-lethal effects of the RTA-Bddsx system were heritable and functioned well in B. dorsalis. Some transformed female flies were observed, and these unexpected results were attributed to the loss of the intact transgene after genomic PCR analyses. CONCLUSION This transgenic study provides direct evidence for the female-specific lethal effects of RTA-Bddsx in B. dorsalis and offers a novel and promising approach for the control of B. dorsalis in the future. © 2015 Society of Chemical Industry.
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Affiliation(s)
- Chun-Yen Huang
- Biotechnology Centre, National Chung-Hsing University, Taichung, Taiwan
| | - Shu-Mei Dai
- Department of Entomology, National Chung-Hsing University, Taichung, Taiwan
| | - Cheng Chang
- Biotechnology Centre, National Chung-Hsing University, Taichung, Taiwan
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77
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Towards understanding pre-mRNA splicing mechanisms and the role of SR proteins. Gene 2016; 587:107-19. [PMID: 27154819 DOI: 10.1016/j.gene.2016.04.057] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 04/30/2016] [Indexed: 01/04/2023]
Abstract
Alternative pre-mRNA splicing provides a source of vast protein diversity by removing non-coding sequences (introns) and accurately linking different exonic regions in the correct reading frame. The regulation of alternative splicing is essential for various cellular functions in both pathological and physiological conditions. In eukaryotic cells, this process is commonly used to increase proteomic diversity and to control gene expression either co- or post-transcriptionally. Alternative splicing occurs within a megadalton-sized, multi-component machine consisting of RNA and proteins; during the splicing process, this complex undergoes dynamic changes via RNA-RNA, protein-protein and RNA-protein interactions. Co-transcriptional splicing functionally integrates the transcriptional machinery, thereby enabling the two processes to influence one another, whereas post-transcriptional splicing facilitates the coupling of RNA splicing with post-splicing events. This review addresses the structural aspects of spliceosomes and the mechanistic implications of their stepwise assembly on the regulation of pre-mRNA splicing. Moreover, the role of phosphorylation-based, signal-induced changes in the regulation of the splicing process is demonstrated.
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Chang C, Huang CY, Dai SM, Atlihan R, Chi H. Genetically Engineered Ricin Suppresses Bactrocera dorsalis (Diptera: Tephritidae) based on Demographic Analysis of Group-Reared Life Table. JOURNAL OF ECONOMIC ENTOMOLOGY 2016; 109:987-992. [PMID: 27122495 DOI: 10.1093/jee/tow091] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 04/01/2016] [Indexed: 06/05/2023]
Abstract
The oriental fruit fly, Bactrocera dorsalis (Hendel), reduces the quantity and quality of many host fruits through the process of oviposition and larval feeding, and this insect has been considered a major insect pest in several Asian countries for decades. Using an earlier-developed, female-specific system that combines the toxicity of the ricin A chain (RTA) and the alternative RNA splicing property of doublesex ( Bddsx ), we show that transgenic male flies harboring the RTA-Bddsx transgene unevenly repress the pest population through inheritable effects. In age-stage, two-sex life-table analyses, high larval mortality and a delay in pupation were observed after introducing the transgene. The high male to female ratio in DsRed + flies demonstrates the lethal effect of ricin on females. The fitness of both the DsRed + - and DsRed - -transformed females was reduced as shown in the decrease of the net reproductive rate ( R0 ), intrinsic rate ( r ), and finite rate (λ) values compared with the wild-type populations. The integrity of the RTA-Bddsx transgene remained in more than 80% of DsRed + males after ten generations, supporting the stable inheritance of the transgene. All of the data from this study support the proposed RTA-Bddsx SIT approach, which provides a species-specific and environmentally friendly method of suppressing, rather than eradiating, B. dorsalis.
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79
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Handler AM. Enhancing the stability and ecological safety of mass-reared transgenic strains for field release by redundant conditional lethality systems. INSECT SCIENCE 2016; 23:225-234. [PMID: 26097098 DOI: 10.1111/1744-7917.12245] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 05/05/2015] [Indexed: 06/04/2023]
Abstract
The genetic manipulation of agriculturally important insects now allows the development of genetic sexing and male sterility systems for more highly efficient biologically-based population control programs, most notably the Sterile Insect Technique (SIT), for both plant and animal insect pests. Tetracycline-suppressible (Tet-off) conditional lethal systems may function together so that transgenic strains will be viable and fertile on a tetracycline-containing diet, but female-lethal and male sterile in tetracycline-free conditions. This would allow their most efficacious use in a unified system for sterile male-only production for SIT. A critical consideration for the field release of such transgenic insect strains, however, is a determination of the frequency and genetic basis of lethality revertant survival. This will provide knowledge essential to evaluating the genetic stability of the lethality system, its environmental safety, and provide the basis for modifications ensuring optimal efficacy. For Tet-off lethal survival determinations, development of large-scale screening protocols should also allow the testing of these modifications, and test the ability of other conditional lethal systems to fully suppress propagation of rare Tet-off survivors. If a dominant temperature sensitive (DTS) pupal lethality system proves efficient for secondary lethality in Drosophila, it may provide the safeguard needed to support the release of sexing/sterility strains, and potentially, the release of unisex lethality strains as a form of genetic male sterility. Should the DTS Prosβ2(1) mutation prove effective for redundant lethality, its high level of structural and functional conservation should allow host-specific cognates to be created for a wide range of insect species.
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Affiliation(s)
- Alfred M Handler
- USDA, Agricultural Research Service, Center for Medical, Agricultural and Veterinary Entomology, Gainesville, FL, 32608, USA
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80
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Huang CY, Huang CC, Dai SM, Chang C. Establishment of an RTA-Bddsx hybrid system for female-specific splicing that can affect the sex ratio of Bactrocera dorsalis (Hendel) after embryonic injection. PEST MANAGEMENT SCIENCE 2016; 72:280-288. [PMID: 25656748 DOI: 10.1002/ps.3990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Revised: 02/02/2015] [Accepted: 02/02/2015] [Indexed: 06/04/2023]
Abstract
BACKGROUND The oriental fruit fly, Bactrocera dorsalis (Hendel), a very destructive insect pest in many areas of Asia, including Taiwan, can cause significant damage by ovipositing in and larval feeding on many kinds of fruit. A female lethal system, combining the splicing property of doublesex (dsx) with the toxicity of ricin A chain (RTA), has been developed. In this system, a modified RTA is separated by Bddsx intron 3; the expressed RNA can only be spliced in females, with toxic effects, whereas the immature RTA in males is harmless. RESULTS Two RTA-Bddsx constructs, clone BE 24-7 and clone CF 26-21, containing Bddsx intron 3 and its flanking exonic sequences, with four nucleotides at the 5'-end and five nucleotides at the 3'-end, correctly spliced in a sex-specific manner. Wild-type and modified RTAs expressed in an Escherichia coli system retained their ability to suppress protein synthesis: 90.4% for Ricin-WT, 71.3% for Ricin-LERQ and 58.0% for Ricin-FEGQ. Embryonic injection of Acp-CF26-21, the RTA-Bddsx gene driven by the actin 5C promoter, resulted in a significant increase in male percentage in the eclosed adults. CONCLUSION Our results indicate that the RTA-Bddsx hybrid system offers a novel and promising approach for oriental fruit fly control.
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Affiliation(s)
- Chun-Yen Huang
- Biotechnology Centre, National Chung-Hsing University, Taichung, Taiwan
| | - Chia Chia Huang
- Biotechnology Centre, National Chung-Hsing University, Taichung, Taiwan
| | - Shu-Mei Dai
- Department of Entomology, National Chung-Hsing University, Taichung, Taiwan
| | - Cheng Chang
- Biotechnology Centre, National Chung-Hsing University, Taichung, Taiwan
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81
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Leftwich PT, Bolton M, Chapman T. Evolutionary biology and genetic techniques for insect control. Evol Appl 2016; 9:212-30. [PMID: 27087849 PMCID: PMC4780389 DOI: 10.1111/eva.12280] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Accepted: 05/25/2015] [Indexed: 01/15/2023] Open
Abstract
The requirement to develop new techniques for insect control that minimize negative environmental impacts has never been more pressing. Here we discuss population suppression and population replacement technologies. These include sterile insect technique, genetic elimination methods such as the release of insects carrying a dominant lethal (RIDL), and gene driving mechanisms offered by intracellular bacteria and homing endonucleases. We also review the potential of newer or underutilized methods such as reproductive interference, CRISPR technology, RNA interference (RNAi), and genetic underdominance. We focus on understanding principles and potential effectiveness from the perspective of evolutionary biology. This offers useful insights into mechanisms through which potential problems may be minimized, in much the same way that an understanding of how resistance evolves is key to slowing the spread of antibiotic and insecticide resistance. We conclude that there is much to gain from applying principles from the study of resistance in these other scenarios - specifically, the adoption of combinatorial approaches to minimize the spread of resistance evolution. We conclude by discussing the focused use of GM for insect pest control in the context of modern conservation planning under land-sparing scenarios.
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Affiliation(s)
- Philip T. Leftwich
- School of Biological SciencesUniversity of East AngliaNorwich Research ParkNorwichUK
| | - Michael Bolton
- School of Biological SciencesUniversity of East AngliaNorwich Research ParkNorwichUK
| | - Tracey Chapman
- School of Biological SciencesUniversity of East AngliaNorwich Research ParkNorwichUK
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Starkbaum J, Braun M, Dabrock P. The synthetic biology puzzle: a qualitative study on public reflections towards a governance framework. SYSTEMS AND SYNTHETIC BIOLOGY 2015; 9:147-157. [PMID: 28392848 PMCID: PMC5383795 DOI: 10.1007/s11693-015-9182-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Accepted: 10/01/2015] [Indexed: 12/02/2022]
Abstract
Synthetic biology is currently one of the most debated emerging biotechnologies. The societal assessment of this technology is primarily based on contributions by scientists and policy makers, who focus mainly on technical challenges and possible risks. While public dialogue is given, it is yet rather limited. This study explores public debates concerning synthetic biology based on a focus group study with citizens from Austria and Germany and contextualises the analysed public views with content from policy reports and previous empirical studies on public engagement. The findings suggest that discussants favoured a gradual implementation process of synthetic biology, which is receptive to questions about the distribution of possible benefits. The discussed topics correspond in many ways with content from policy reports and former investigations, yet the emphasis of the discussions was different for many aspects.
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Affiliation(s)
- Johannes Starkbaum
- Department of Political Science, University of Vienna, Vienna, Austria
- Chair for Systematic Theology II (Ethics), Friedrich-Alexander-University Erlangen-Nuremberg, Kochstraße 6, 91504 Erlangen, Germany
| | - Matthias Braun
- Chair for Systematic Theology II (Ethics), Friedrich-Alexander-University Erlangen-Nuremberg, Kochstraße 6, 91504 Erlangen, Germany
| | - Peter Dabrock
- Chair for Systematic Theology II (Ethics), Friedrich-Alexander-University Erlangen-Nuremberg, Kochstraße 6, 91504 Erlangen, Germany
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83
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Yan Y, Scott MJ. A transgenic embryonic sexing system for the Australian sheep blow fly Lucilia cuprina. Sci Rep 2015; 5:16090. [PMID: 26537204 PMCID: PMC4633611 DOI: 10.1038/srep16090] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Accepted: 10/07/2015] [Indexed: 11/09/2022] Open
Abstract
Genetic approaches, including the sterile insect technique (SIT), have previously been considered for control of the Australian sheep blow fly Lucilia cuprina, a major pest of sheep. In an SIT program, females consume 50% of the diet but are ineffective as control agents and compete with females in the field for mating with sterile males, thereby decreasing the efficiency of the program. Consequently, transgenic sexing strains of L. cuprina were developed that produce 100% males when raised on diet that lacks tetracycline. However, as females die mostly at the pupal stage, rearing costs would not be significantly reduced. Here we report the development of transgenic embryonic sexing strains of L. cuprina. In these strains, the Lsbnk cellularization gene promoter drives high levels of expression of the tetracycline transactivator (tTA) in the early embryo. In the absence of tetracycline, tTA activates expression of the Lshid proapoptotic gene, leading to death of the embryo. Sex-specific RNA splicing of Lshid transcripts ensures that only female embryos die. Embryonic sexing strains were also made by combining the Lsbnk-tTA and tetO-Lshid components into a single gene construct, which will facilitate transfer of the technology to other major calliphorid livestock pests.
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Affiliation(s)
- Ying Yan
- Department of Entomology, North Carolina State University, Campus Box 7613, Raleigh, NC, 27695-7613
| | - Maxwell J Scott
- Department of Entomology, North Carolina State University, Campus Box 7613, Raleigh, NC, 27695-7613
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Lievens A, Petrillo M, Querci M, Patak A. Genetically modified animals: Options and issues for traceability and enforcement. Trends Food Sci Technol 2015. [DOI: 10.1016/j.tifs.2015.05.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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85
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Harvey-Samuel T, Morrison NI, Walker AS, Marubbi T, Yao J, Collins HL, Gorman K, Davies TGE, Alphey N, Warner S, Shelton AM, Alphey L. Pest control and resistance management through release of insects carrying a male-selecting transgene. BMC Biol 2015; 13:49. [PMID: 26179401 PMCID: PMC4504119 DOI: 10.1186/s12915-015-0161-1] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Accepted: 06/23/2015] [Indexed: 11/10/2022] Open
Abstract
Background Development and evaluation of new insect pest management tools is critical for overcoming over-reliance upon, and growing resistance to, synthetic, biological and plant-expressed insecticides. For transgenic crops expressing insecticidal proteins from the bacterium Bacillus thuringiensis (‘Bt crops’) emergence of resistance is slowed by maintaining a proportion of the crop as non-Bt varieties, which produce pest insects unselected for resistance. While this strategy has been largely successful, multiple cases of Bt resistance have now been reported. One new approach to pest management is the use of genetically engineered insects to suppress populations of their own species. Models suggest that released insects carrying male-selecting (MS) transgenes would be effective agents of direct, species-specific pest management by preventing survival of female progeny, and simultaneously provide an alternative insecticide resistance management strategy by introgression of susceptibility alleles into target populations. We developed a MS strain of the diamondback moth, Plutella xylostella, a serious global pest of crucifers. MS-strain larvae are reared as normal with dietary tetracycline, but, when reared without tetracycline or on host plants, only males will survive to adulthood. We used this strain in glasshouse-cages to study the effect of MS male P. xylostella releases on target pest population size and spread of Bt resistance in these populations. Results Introductions of MS-engineered P. xylostella males into wild-type populations led to rapid pest population decline, and then elimination. In separate experiments on broccoli plants, relatively low-level releases of MS males in combination with broccoli expressing Cry1Ac (Bt broccoli) suppressed population growth and delayed the spread of Bt resistance. Higher rates of MS male releases in the absence of Bt broccoli were also able to suppress P. xylostella populations, whereas either low-level MS male releases or Bt broccoli alone did not. Conclusions These results support theoretical modeling, indicating that MS-engineered insects can provide a powerful pest population suppressing effect, and could effectively augment current Bt resistance management strategies. We conclude that, subject to field confirmation, MS insects offer an effective and versatile control option against P. xylostella and potentially other pests, and may reduce reliance on and protect insecticide-based approaches, including Bt crops.
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Affiliation(s)
- Tim Harvey-Samuel
- Department of Zoology, University of Oxford, South Parks Road, Oxford, Oxfordshire, OX1 3PS, UK.,Oxitec Ltd, 71 Innovation Drive, Milton Park, Oxford, Oxfordshire, OX14 4RQ, UK
| | - Neil I Morrison
- Oxitec Ltd, 71 Innovation Drive, Milton Park, Oxford, Oxfordshire, OX14 4RQ, UK.
| | - Adam S Walker
- Oxitec Ltd, 71 Innovation Drive, Milton Park, Oxford, Oxfordshire, OX14 4RQ, UK
| | - Thea Marubbi
- Oxitec Ltd, 71 Innovation Drive, Milton Park, Oxford, Oxfordshire, OX14 4RQ, UK
| | - Ju Yao
- Cornell University/NYSAES, Barton Lab 416, 630 W. North Street, Geneva, NY, 14456, USA.,Institute of Plant Protection, Xinjiang Academy of Agricultural Science, Urumqi, China
| | - Hilda L Collins
- Cornell University/NYSAES, Barton Lab 416, 630 W. North Street, Geneva, NY, 14456, USA
| | - Kevin Gorman
- Oxitec Ltd, 71 Innovation Drive, Milton Park, Oxford, Oxfordshire, OX14 4RQ, UK
| | - T G Emyr Davies
- Biological Chemistry & Crop Protection Department, Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK
| | - Nina Alphey
- Department of Zoology, University of Oxford, South Parks Road, Oxford, Oxfordshire, OX1 3PS, UK.,Department of Life Sciences, Imperial College London, Silwood Park Campus, Buckhurst Road, Ascot, Berkshire, SL5 7PY, UK
| | - Simon Warner
- Oxitec Ltd, 71 Innovation Drive, Milton Park, Oxford, Oxfordshire, OX14 4RQ, UK
| | - Anthony M Shelton
- Cornell University/NYSAES, Barton Lab 416, 630 W. North Street, Geneva, NY, 14456, USA
| | - Luke Alphey
- Department of Zoology, University of Oxford, South Parks Road, Oxford, Oxfordshire, OX1 3PS, UK.,Oxitec Ltd, 71 Innovation Drive, Milton Park, Oxford, Oxfordshire, OX14 4RQ, UK.,The Pirbright Institute, Woking, Surrey, GU24 0NF, UK
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86
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Liu G, Wu Q, Li J, Zhang G, Wan F. RNAi-Mediated Knock-Down of transformer and transformer 2 to Generate Male-Only Progeny in the Oriental Fruit Fly, Bactrocera dorsalis (Hendel). PLoS One 2015; 10:e0128892. [PMID: 26057559 PMCID: PMC4461288 DOI: 10.1371/journal.pone.0128892] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Accepted: 05/02/2015] [Indexed: 12/04/2022] Open
Abstract
The transformer (tra) gene appears to act as the genetic switch that promotes female development by interaction with the transformer2 (tra-2) gene in several dipteran species including the Medfly, housefly and Drosophila melanogaster. In this study, we describe the isolation, expression and function of tra and tra-2 in the economically important agricultural pest, the oriental fruit fly, Bactrocera dorsalis (Hendel). Bdtra and Bdtra-2 are similar to their homologs from other tephritid species. Bdtra demonstrated sex-specific transcripts: one transcript in females and two transcripts in males. In contrast, Bdtra-2 only had one transcript that was common to males and females, which was transcribed continuously in different adult tissues and developmental stages. Bdtra-2 and the female form of Bdtra were maternally inherited in eggs, whereas the male form of Bdtra was not detectable until embryos of 1 and 2 h after egg laying. Function analyses of Bdtra and Bdtra-2 indicated that both were indispensable for female development, as nearly 100% males were obtained with embryonic RNAi against either Bdtra or Bdtra-2. The fertility of these RNAi-generated males was subsequently tested. More than 80% of RNAi-generated males could mate and the mated females could lay eggs, but only 40-48.6% males gave rise to progeny. In XX-reversed males and intersex individuals, no clear female gonadal morphology was observed after dissection. These results shed light on the development of a genetic sexing system with male-only release for this agricultural pest.
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Affiliation(s)
- Guiqing Liu
- Department of Biological Invasions, State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
- Guangdong Key Laboratory of Integrated Pest Management in Agriculture, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Guangdong Entomological Institute, Guangzhou, China
| | - Qiang Wu
- Department of Biological Invasions, State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Jianwei Li
- Department of Biological Invasions, State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Guifen Zhang
- Department of Biological Invasions, State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Fanghao Wan
- Department of Biological Invasions, State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
- Agricultural Genome Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
- * E-mail:
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87
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Xu J, Bi H, Chen R, Aslam AFM, Li Z, Ling L, Zeng B, Huang Y, Tan A. Transgenic characterization of two testis-specific promoters in the silkworm, Bombyx mori. INSECT MOLECULAR BIOLOGY 2015; 24:183-190. [PMID: 25387604 DOI: 10.1111/imb.12144] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Sex-specific regulatory elements are key components for developing insect genetic sexing systems. The current insect genetic sexing system mainly uses a female-specific modification system whereas little success was reported on male-specific genetic modification. In the silkworm Bombyx mori, a lepidopteran model insect with economic importance, a transgene-based, female-specific lethality system has been established based on sex-specific alternative splicing factors and a female-specific promoter BmVgp (vitellogenin promoter) has been identified. However, no male-specific regulatory elements have yet been identified. Here we report the transgenic identification of two promoters that drive reporter gene expression in a testis-specific manner in B. mori. Putative promoter sequences from the B. mori Radial spoke head 1 gene (BmR1) and beta-tubulin 4 gene (Bmβ4) were introduced using piggybac-based germline transformation. In transgenic silkworms, expression of the reporter gene enhanced green fluorescent protein (EGFP) directed by either BmR1 promoter (BmR1p) or Bmβ4p showed precisely testis-specific manners from the larval to adult stage. Furthermore, EGFP expression of these two transgenic lines showed different localization in the testis, indicating that BmR1p or Bmβ4p might be used as distinct regulatory elements in directing testis-specific gene expression. Identification of these testis-specific promoters not only contributes to a better understanding of testis-specific gene function in insects, but also has potential applications in sterile insect techniques for pest management.
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Affiliation(s)
- J Xu
- Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China; University of Chinese Academy of Sciences, Beijing, China
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88
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Lin X, Wang G. Development of a RNAi-based release of insects carrying a dominant lethal (RIDL) system in Drosophila melanogaster. Sci Bull (Beijing) 2015. [DOI: 10.1007/s11434-014-0667-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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89
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Akbari OS, Chen CH, Marshall JM, Huang H, Antoshechkin I, Hay BA. Novel synthetic Medea selfish genetic elements drive population replacement in Drosophila; a theoretical exploration of Medea-dependent population suppression. ACS Synth Biol 2014; 3:915-28. [PMID: 23654248 DOI: 10.1021/sb300079h] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Insects act as vectors for diseases of plants, animals, and humans. Replacement of wild insect populations with genetically modified individuals unable to transmit disease provides a potentially self-perpetuating method of disease prevention. Population replacement requires a gene drive mechanism in order to spread linked genes mediating disease refractoriness through wild populations. We previously reported the creation of synthetic Medea selfish genetic elements able to drive population replacement in Drosophila. These elements use microRNA-mediated silencing of myd88, a maternally expressed gene required for embryonic dorso-ventral pattern formation, coupled with early zygotic expression of a rescuing transgene, to bring about gene drive. Medea elements that work through additional mechanisms are needed in order to be able to carry out cycles of population replacement and/or remove existing transgenes from the population, using second-generation elements that spread while driving first-generation elements out of the population. Here we report the synthesis and population genetic behavior of two new synthetic Medea elements that drive population replacement through manipulation of signaling pathways involved in cellular blastoderm formation or Notch signaling, demonstrating that in Drosophila Medea elements can be generated through manipulation of diverse signaling pathways. We also describe the mRNA and small RNA changes in ovaries and early embryos associated from Medea-bearing females. Finally, we use modeling to illustrate how Medea elements carrying genes that result in diapause-dependent female lethality could be used to bring about population suppression.
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Affiliation(s)
- Omar S. Akbari
- Division of
Biology, MC 156-29, California Institute of Technology, Pasadena, California
91125, United States
| | - Chun-Hong Chen
- Institute of Molecular and Genomic
Medicine, National Heath Research Institutes, 35 Kayen Road Zhunan Mioali, Taiwan
| | - John M. Marshall
- MRC Center for Outbreak Analysis & Modeling, Department of Infectious Disease Epidemiology, Imperial College London, London W2 1PG, U.K
| | - Haixia Huang
- Division of
Biology, MC 156-29, California Institute of Technology, Pasadena, California
91125, United States
| | - Igor Antoshechkin
- Division of
Biology, MC 156-29, California Institute of Technology, Pasadena, California
91125, United States
| | - Bruce A. Hay
- Division of
Biology, MC 156-29, California Institute of Technology, Pasadena, California
91125, United States
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90
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Wang Y, Liu J, Huang BO, Xu YM, Li J, Huang LF, Lin J, Zhang J, Min QH, Yang WM, Wang XZ. Mechanism of alternative splicing and its regulation. Biomed Rep 2014; 3:152-158. [PMID: 25798239 DOI: 10.3892/br.2014.407] [Citation(s) in RCA: 236] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Accepted: 12/10/2014] [Indexed: 12/11/2022] Open
Abstract
Alternative splicing of precursor mRNA is an essential mechanism to increase the complexity of gene expression, and it plays an important role in cellular differentiation and organism development. Regulation of alternative splicing is a complicated process in which numerous interacting components are at work, including cis-acting elements and trans-acting factors, and is further guided by the functional coupling between transcription and splicing. Additional molecular features, such as chromatin structure, RNA structure and alternative transcription initiation or alternative transcription termination, collaborate with these basic components to generate the protein diversity due to alternative splicing. All these factors contributing to this one fundamental biological process add up to a mechanism that is critical to the proper functioning of cells. Any corruption of the process may lead to disruption of normal cellular function and the eventuality of disease. Cancer is one of those diseases, where alternative splicing may be the basis for the identification of novel diagnostic and prognostic biomarkers, as well as new strategies for therapy. Thus, an in-depth understanding of alternative splicing regulation has the potential not only to elucidate fundamental biological principles, but to provide solutions for various diseases.
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Affiliation(s)
- Yan Wang
- Department of Clinical Laboratory Medicine, The Second Affiliated Hospital of Nanchang University, Nanchang 330006, P.R. China
| | - Jing Liu
- Department of Clinical Laboratory Medicine, The Second Affiliated Hospital of Nanchang University, Nanchang 330006, P.R. China
| | - B O Huang
- Department of Clinical Laboratory Medicine, The Second Affiliated Hospital of Nanchang University, Nanchang 330006, P.R. China
| | - Yan-Mei Xu
- Department of Clinical Laboratory Medicine, The Second Affiliated Hospital of Nanchang University, Nanchang 330006, P.R. China
| | - Jing Li
- Department of Clinical Laboratory Medicine, The First Affiliated Hospital of Nanchang University, Nanchang 330006, P.R. China
| | - Lin-Feng Huang
- Department of Clinical Laboratory Medicine, The Second Affiliated Hospital of Nanchang University, Nanchang 330006, P.R. China
| | - Jin Lin
- Department of Clinical Laboratory Medicine, The Second Affiliated Hospital of Nanchang University, Nanchang 330006, P.R. China
| | - Jing Zhang
- Department of Clinical Laboratory Medicine, The Second Affiliated Hospital of Nanchang University, Nanchang 330006, P.R. China
| | - Qing-Hua Min
- Department of Clinical Laboratory Medicine, The Second Affiliated Hospital of Nanchang University, Nanchang 330006, P.R. China
| | - Wei-Ming Yang
- Department of Clinical Laboratory Medicine, The Second Affiliated Hospital of Nanchang University, Nanchang 330006, P.R. China
| | - Xiao-Zhong Wang
- Department of Clinical Laboratory Medicine, The Second Affiliated Hospital of Nanchang University, Nanchang 330006, P.R. China
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91
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Sirot LK, Wong A, Chapman T, Wolfner MF. Sexual conflict and seminal fluid proteins: a dynamic landscape of sexual interactions. Cold Spring Harb Perspect Biol 2014; 7:a017533. [PMID: 25502515 DOI: 10.1101/cshperspect.a017533] [Citation(s) in RCA: 102] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Sexual reproduction requires coordinated contributions from both sexes to proceed efficiently. However, the reproductive strategies that the sexes adopt often have the potential to give rise to sexual conflict because they can result in divergent, sex-specific costs and benefits. These conflicts can occur at many levels, from molecular to behavioral. Here, we consider sexual conflict mediated through the actions of seminal fluid proteins. These proteins provide many excellent examples in which to trace the operation of sexual conflict from molecules through to behavior. Seminal fluid proteins are made by males and provided to females during mating. As agents that can modulate egg production at several steps, as well as reproductive behavior, sperm "management," and female feeding, activity, and longevity, the actions of seminal proteins are prime targets for sexual conflict. We review these actions in the context of sexual conflict. We discuss genomic signatures in seminal protein (and related) genes that are consistent with current or previous sexual conflict. Finally, we note promising areas for future study and highlight real-world practical situations that will benefit from understanding the nature of sexual conflicts mediated by seminal proteins.
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Affiliation(s)
- Laura K Sirot
- Department of Biology, College of Wooster, Wooster, Ohio 44691
| | - Alex Wong
- Department of Biology, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Tracey Chapman
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, United Kingdom
| | - Mariana F Wolfner
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14853
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92
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Salvemini M, Arunkumar KP, Nagaraju J, Sanges R, Petrella V, Tomar A, Zhang H, Zheng W, Saccone G. De novo assembly and transcriptome analysis of the Mediterranean fruit fly Ceratitis capitata early embryos. PLoS One 2014; 9:e114191. [PMID: 25474564 PMCID: PMC4256415 DOI: 10.1371/journal.pone.0114191] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Accepted: 11/05/2014] [Indexed: 01/04/2023] Open
Abstract
The agricultural pest Ceratitis capitata, also known as the Mediterranean fruit fly or Medfly, belongs to the Tephritidae family, which includes a large number of other damaging pest species. The Medfly has been the first non-drosophilid fly species which has been genetically transformed paving the way for designing genetic-based pest control strategies. Furthermore, it is an experimentally tractable model, in which transient and transgene-mediated RNAi have been successfully used. We applied Illumina sequencing to total RNA preparations of 8–10 hours old embryos of C. capitata, This developmental window corresponds to the blastoderm cellularization stage. In summary, we assembled 42,614 transcripts which cluster in 26,319 unique transcripts of which 11,045 correspond to protein coding genes; we identified several hundreds of long ncRNAs; we found an enrichment of transcripts encoding RNA binding proteins among the highly expressed transcripts, such as CcTRA-2, known to be necessary to establish and, most likely, to maintain female sex of C. capitata. Our study is the first de novo assembly performed for Ceratitis capitata based on Illumina NGS technology during embryogenesis and it adds novel data to the previously published C. capitata EST databases. We expect that it will be useful for a variety of applications such as gene cloning and phylogenetic analyses, as well as to advance genetic research and biotechnological applications in the Medfly and other related Tephritidae.
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Affiliation(s)
- Marco Salvemini
- Department of Biology, University of Naples Federico II, Naples, Italy
| | | | | | - Remo Sanges
- Stazione Zoologica "Anton Dohrn", Naples, Italy
| | - Valeria Petrella
- Department of Biology, University of Naples Federico II, Naples, Italy
| | - Archana Tomar
- Centre for DNA Fingerprinting and Diagnostics, Hyderabad, India
| | - Hongyu Zhang
- State Key Laboratory of Agricultural Microbiology and Institute of Urban and Horticultural Pests, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, People's Republic of China
| | - Weiwei Zheng
- State Key Laboratory of Agricultural Microbiology and Institute of Urban and Horticultural Pests, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, People's Republic of China
| | - Giuseppe Saccone
- Department of Biology, University of Naples Federico II, Naples, Italy
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93
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Isasawin S, Aketarawong N, Lertsiri S, Thanaphum S. Development of a genetic sexing strain in Bactrocera carambolae (Diptera: Tephritidae) by introgression of sex sorting components from B. dorsalis, Salaya1 strain. BMC Genet 2014; 15 Suppl 2:S2. [PMID: 25471905 PMCID: PMC4255791 DOI: 10.1186/1471-2156-15-s2-s2] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The carambola fruit fly, Bactrocera carambolae Drew & Hancock is a high profile key pest that is widely distributed in the southwestern ASEAN region. In addition, it has trans-continentally invaded Suriname, where it has been expanding east and southward since 1975. This fruit fly belongs to Bactrocera dorsalis species complex. The development and application of a genetic sexing strain (Salaya1) of B. dorsalis sensu stricto (s.s.) (Hendel) for the sterile insect technique (SIT) has improved the fruit fly control. However, matings between B. dorsalis s.s. and B. carambolae are incompatible, which hinder the application of the Salaya1 strain to control the carambola fruit fly. To solve this problem, we introduced genetic sexing components from the Salaya1 strain into the B. carambolae genome by interspecific hybridization. RESULTS Morphological characteristics, mating competitiveness, male pheromone profiles, and genetic relationships revealed consistencies that helped to distinguish Salaya1 and B. carambolae strains. A Y-autosome translocation linking the dominant wild-type allele of white pupae gene and a free autosome carrying a recessive white pupae homologue from the Salaya1 strain were introgressed into the gene pool of B. carambolae. A panel of Y-pseudo-linked microsatellite loci of the Salaya1 strain served as markers for the introgression experiments. This resulted in a newly derived genetic sexing strain called Salaya5, with morphological characteristics corresponding to B. carambolae. The rectal gland pheromone profile of Salaya5 males also contained a distinctive component of B. carambolae. Microsatellite DNA analyses confirmed the close genetic relationships between the Salaya5 strain and wild B. carambolae populations. Further experiments showed that the sterile males of Salaya5 can compete with wild males for mating with wild females in field cage conditions. CONCLUSIONS Introgression of sex sorting components from the Salaya1 strain to a closely related B. carambolae strain generated a new genetic sexing strain, Salaya5. Morphology-based taxonomic characteristics, distinctive pheromone components, microsatellite DNA markers, genetic relationships, and mating competitiveness provided parental baseline data and validation tools for the new strain. The Salaya5 strain shows a close similarity with those features in the wild B. carambolae strain. In addition, mating competitiveness tests suggested that Salaya5 has a potential to be used in B. carambolae SIT programs based on male-only releases.
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94
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Scott MJ. Development and evaluation of male-only strains of the Australian sheep blowfly, Lucilia cuprina. BMC Genet 2014; 15 Suppl 2:S3. [PMID: 25472415 PMCID: PMC4255793 DOI: 10.1186/1471-2156-15-s2-s3] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The Australian sheep blowfly Lucilia cuprina (Wiedemann) is a major pest of sheep in Australia and New Zealand. From the 1960s to the 1980s there was a major effort to develop "field female killing" or FFK strains of L. cuprina that could be used for a cost-effective genetic control program. The FFK strains carried eye color mutations that were lethal to females in the field but not under conditions in the mass rearing facility. Males did not die in the field as normal copies of the eye color genes had been translocated to the Y chromosome and an autosome. Although the FFK strains showed some promise in field tests, a genetic control program in mainland Australia was never implemented for several reasons including instability of the FFK strains during mass rearing. A stable transgenic strain of L. cuprina that carried one or more dominant repressible female lethal genes offered the potential for efficient genetic control of blowfly populations. Here I review our research on tetracycline-repressible female lethal genetic systems, Lucilia germ-line transformation and sex determination genes that ultimately led to the successful development of transgenic "male-only" strains of L. cuprina. The technology developed for L. cuprina should be directly transferable to other blowfly livestock pests including L. sericata and the New World and Old World screwworm. 29
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95
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Salvemini M, D'Amato R, Petrella V, Ippolito D, Ventre G, Zhang Y, Saccone G. Subtractive and differential hybridization molecular analyses of Ceratitis capitata XX/XY versus XX embryos to search for male-specific early transcribed genes. BMC Genet 2014; 15 Suppl 2:S5. [PMID: 25472628 PMCID: PMC4255797 DOI: 10.1186/1471-2156-15-s2-s5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
The agricultural pest Ceratitis capitata, also known as the Mediterranean fruit fly or Medfly, is a fruit crop pest of very high economic relevance in different continents. The strategy to separate Ceratitis males from females (sexing) in mass rearing facilities is a useful step before the sterilization and release of male-only flies in Sterile Insect Technique control programs (SIT). The identification of genes having early embryonic male-specific expression, including Y-linked genes, such as the Maleness factor, could help to design novel and improved methods of sexing in combination with transgenesis, aiming to confer conditional female-specific lethality or female-to-male sexual reversal. We used a combination of Suppression Subtractive Hybrydization (SSH), Mirror Orientation Selection (MOS) and differential screening hybridization (DSH) techniques to approach the problem of isolating corresponding mRNAs expressed in XX/XY embryos versus XX-only embryos during a narrow developmental window (8-10 hours after egg laying, AEL ). Here we describe a novel strategy we have conceived to obtain relatively large amounts of XX-only embryos staged at 8-10 h AEL and so to extract few micrograms of polyA+ required to apply the complex technical procedure. The combination of these 3 techniques led to the identification of a Y-linked putative gene, CcGm2, sharing high sequence identity to a paralogous gene, CcGm1, localized either on an autosome or on the X chromosome. We propose that CcGm2 is a first interesting putative Y-linked gene which could play a role in sex determination. The function exterted by this gene should be investigated by novel genetic tools, such as CRISPR-CAS9, which will permit to target only the Y-linked paralogue, avoiding to interfere with the autosomal or X-linked paralogue function.
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96
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How functional genomics will impact fruit fly pest control: the example of the Mediterranean fruit fly, Ceratitis capitata. BMC Genet 2014; 15 Suppl 2:S11. [PMID: 25471105 PMCID: PMC4255779 DOI: 10.1186/1471-2156-15-s2-s11] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The highly invasive agricultural insect pest Ceratitis capitata (Diptera: Tephritidae) is the most thoroughly studied tephritid fruit fly at the genetic and molecular levels. It has become a model for the analysis of fruit fly invasions and for the development of area-wide integrated pest management (AW-IPM) programmes based on the environmentally-friendly Sterile Insect Technique (SIT). Extensive transcriptome resources and the recently released genome sequence are making it possible to unravel several aspects of the medfly reproductive biology and behaviour, opening new opportunities for comparative genomics and barcoding for species identification. New genes, promotors and regulatory sequences are becoming available for the development/improvement of highly competitive sexing strains, for the monitoring of sterile males released in the field and for determining the mating status of wild females. The tools developed in this species have been transferred to other tephritids that are also the subject of SIT programmes.
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97
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Eckermann KN, Dippel S, KaramiNejadRanjbar M, Ahmed HM, Curril IM, Wimmer EA. Perspective on the combined use of an independent transgenic sexing and a multifactorial reproductive sterility system to avoid resistance development against transgenic Sterile Insect Technique approaches. BMC Genet 2014; 15 Suppl 2:S17. [PMID: 25471733 PMCID: PMC4255789 DOI: 10.1186/1471-2156-15-s2-s17] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Background The Sterile Insect Technique (SIT) is an accepted species-specific genetic control approach that acts as an insect birth control measure, which can be improved by biotechnological engineering to facilitate its use and widen its applicability. First transgenic insects carrying a single killing system have already been released in small scale trials. However, to evade resistance development to such transgenic approaches, completely independent ways of transgenic killing should be established and combined. Perspective Most established transgenic sexing and reproductive sterility systems are based on the binary tTA expression system that can be suppressed by adding tetracycline to the food. However, to create 'redundant killing' an additional independent conditional expression system is required. Here we present a perspective on the use of a second food-controllable binary expression system - the inducible Q system - that could be used in combination with site-specific recombinases to generate independent transgenic killing systems. We propose the combination of an already established transgenic embryonic sexing system to meet the SIT requirement of male-only releases based on the repressible tTA system together with a redundant male-specific reproductive sterility system, which is activated by Q-system controlled site-specific recombination and is based on a spermatogenesis-specifically expressed endonuclease acting on several species-specific target sites leading to chromosome shredding. Conclusion A combination of a completely independent transgenic sexing and a redundant reproductive male sterility system, which do not share any active components and mediate the induced lethality by completely independent processes, would meet the 'redundant killing' criteria for suppression of resistance development and could therefore be employed in large scale long-term suppression programs using biotechnologically enhanced SIT.
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Meza JS, Díaz-Fleischer F, Sánchez-Velásquez LR, Zepeda-Cisneros CS, Handler AM, Schetelig MF. Fitness cost implications of PhiC31-mediated site-specific integrations in target-site strains of the Mexican fruit fly, Anastrepha ludens (Diptera: Tephritidae). PLoS One 2014; 9:e109690. [PMID: 25303238 PMCID: PMC4193812 DOI: 10.1371/journal.pone.0109690] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2014] [Accepted: 09/10/2014] [Indexed: 01/14/2023] Open
Abstract
Site-specific recombination technologies are powerful new tools for the manipulation of genomic DNA in insects that can improve transgenesis strategies such as targeting transgene insertions, allowing transgene cassette exchange and DNA mobilization for transgene stabilization. However, understanding the fitness cost implications of these manipulations for transgenic strain applications is critical. In this study independent piggyBac-mediated attP target-sites marked with DsRed were created in several genomic positions in the Mexican fruit fly, Anastrepha ludens. Two of these strains, one having an autosomal (attP_F7) and the other a Y-linked (attP_2-M6y) integration, exhibited fitness parameters (dynamic demography and sexual competitiveness) similar to wild type flies. These strains were thus selected for targeted insertion using, for the first time in mexfly, the phiC31-integrase recombination system to insert an additional EGFP-marked transgene to determine its effect on host strain fitness. Fitness tests showed that the integration event in the int_2-M6y recombinant strain had no significant effect, while the int_F7 recombinant strain exhibited significantly lower fitness relative to the original attP_F7 target-site host strain. These results indicate that while targeted transgene integrations can be achieved without an additional fitness cost, at some genomic positions insertion of additional DNA into a previously integrated transgene can have a significant negative effect. Thus, for targeted transgene insertions fitness costs must be evaluated both previous to and subsequent to new site-specific insertions in the target-site strain.
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Affiliation(s)
- José S. Meza
- Programa Moscafrut, SAGARPA-IICA, Metapa de Domínguez, Chiapas, México
- Instituto de Biotecnología y Ecología Aplicada (INBIOTECA), Universidad Veracruzana, Xalapa, Veracruz, México
| | - Francisco Díaz-Fleischer
- Instituto de Biotecnología y Ecología Aplicada (INBIOTECA), Universidad Veracruzana, Xalapa, Veracruz, México
| | - Lázaro R. Sánchez-Velásquez
- Instituto de Biotecnología y Ecología Aplicada (INBIOTECA), Universidad Veracruzana, Xalapa, Veracruz, México
| | | | - Alfred M. Handler
- Center for Medical, Agricultural, and Veterinary Entomology, Agricultural Research Service, U.S. Department of Agriculture, Gainesville, Florida, United States of America
| | - Marc F. Schetelig
- Center for Medical, Agricultural, and Veterinary Entomology, Agricultural Research Service, U.S. Department of Agriculture, Gainesville, Florida, United States of America
- Justus-Liebig-University Giessen, Institute for Phytopathology and Applied Zoology, Giessen, Germany
- * E-mail:
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Leftwich PT, Koukidou M, Rempoulakis P, Gong HF, Zacharopoulou A, Fu G, Chapman T, Economopoulos A, Vontas J, Alphey L. Genetic elimination of field-cage populations of Mediterranean fruit flies. Proc Biol Sci 2014; 281:20141372. [PMID: 25122230 PMCID: PMC4150327 DOI: 10.1098/rspb.2014.1372] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Accepted: 07/17/2014] [Indexed: 11/12/2022] Open
Abstract
The Mediterranean fruit fly (medfly, Ceratitis capitata Wiedemann) is a pest of over 300 fruits, vegetables and nuts. The sterile insect technique (SIT) is a control measure used to reduce the reproductive potential of populations through the mass release of sterilized male insects that mate with wild females. However, SIT flies can display poor field performance, due to the effects of mass-rearing and of the irradiation process used for sterilization. The development of female-lethal RIDL (release of insects carrying a dominant lethal) strains for medfly can overcome many of the problems of SIT associated with irradiation. Here, we present life-history characterizations for two medfly RIDL strains, OX3864A and OX3647Q. Our results show (i) full functionality of RIDL, (ii) equivalency of RIDL and wild-type strains for life-history characteristics, and (iii) a high level of sexual competitiveness against both wild-type and wild-derived males. We also present the first proof-of-principle experiment on the use of RIDL to eliminate medfly populations. Weekly releases of OX3864A males into stable populations of wild-type medfly caused a successive decline in numbers, leading to eradication. The results show that genetic control can provide an effective alternative to SIT for the control of pest insects.
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Affiliation(s)
- Philip T Leftwich
- Oxitec Limited, 71 Innovation Drive, Milton Park, Oxford OX14 4RQ, UK School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, Norfolk NR4 7TJ, UK
| | - Martha Koukidou
- Oxitec Limited, 71 Innovation Drive, Milton Park, Oxford OX14 4RQ, UK
| | - Polychronis Rempoulakis
- Oxitec Limited, 71 Innovation Drive, Milton Park, Oxford OX14 4RQ, UK Faculty of Biotechnology and Applied Biology, Department of Biology, University of Crete, Heraklion, Crete, Greece
| | - Hong-Fei Gong
- Oxitec Limited, 71 Innovation Drive, Milton Park, Oxford OX14 4RQ, UK
| | - Antigoni Zacharopoulou
- Department of Biology, Division of Genetics, Cell and Developmental Biology, University of Patras, Patras, Greece
| | - Guoliang Fu
- Oxitec Limited, 71 Innovation Drive, Milton Park, Oxford OX14 4RQ, UK
| | - Tracey Chapman
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, Norfolk NR4 7TJ, UK
| | - Aris Economopoulos
- Faculty of Biotechnology and Applied Biology, Department of Biology, University of Crete, Heraklion, Crete, Greece
| | - John Vontas
- Faculty of Biotechnology and Applied Biology, Department of Biology, University of Crete, Heraklion, Crete, Greece
| | - Luke Alphey
- Oxitec Limited, 71 Innovation Drive, Milton Park, Oxford OX14 4RQ, UK Department of Zoology, University of Oxford, South Parks Road, Oxford OX1 3PS, UK The Pirbright Institute, Ash Road, Woking GU24 0NF, UK
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100
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Slade G, Morrison N. Developing GM insects for sustainable pest control in agriculture and human health. BMC Proc 2014. [PMCID: PMC4204071 DOI: 10.1186/1753-6561-8-s4-o43] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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