1
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Sun R, Raban R, Akbari OS. CRISPR-Cas9 Methods and Key Considerations in the Production of Aedes aegypti Mutant Strains. Cold Spring Harb Protoc 2023; 2023:607-613. [PMID: 36931732 PMCID: PMC10901255 DOI: 10.1101/pdb.top107693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/19/2023]
Abstract
Since the characterization of the CRISPR-Cas9 system in prokaryotes, it has become the prime choice in gene editing because of its exceptional flexibility, ease of use, high efficiency, and superior specificity. As a result, CRISPR-Cas9-mediated gene-editing technologies have enabled researchers not only to engineer transgenic animal strains with site-directed insertions more efficiently but also to generate desired mutants for previously intractable species. One such species is the invasive yellow fever mosquito, Aedes aegypti, which is notorious for its ability to transmit many blood-borne human pathogens. Methods for developing new transgenic strains of the yellow fever mosquito may aid in the effort to control its populations and provide significant benefits for the public. Here, we provide an overview of injection and noninjection methods for generating transgenic mosquitoes and also highlight important experimental design features.
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Affiliation(s)
- Ruichen Sun
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, California 92093, USA
| | - Robyn Raban
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, California 92093, USA
| | - Omar S Akbari
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, California 92093, USA
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2
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Raban R, Gendron WAC, Akbari OS. A perspective on the expansion of the genetic technologies to support the control of neglected vector-borne diseases and conservation. Front Trop Dis 2022. [DOI: 10.3389/fitd.2022.999273] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023] Open
Abstract
Genetic-based technologies are emerging as promising tools to support vector population control. Vectors of human malaria and dengue have been the main focus of these development efforts, but in recent years these technologies have become more flexible and adaptable and may therefore have more wide-ranging applications. Culex quinquefasciatus, for example, is the primary vector of avian malaria in Hawaii and other tropical islands. Avian malaria has led to the extinction of numerous native bird species and many native bird species continue to be threatened as climate change is expanding the range of this mosquito. Genetic-based technologies would be ideal to support avian malaria control as they would offer alternatives to interventions that are difficult to implement in natural areas, such as larval source reduction, and limit the need for chemical insecticides, which can harm beneficial species in these natural areas. This mosquito is also an important vector of human diseases, such as West Nile and Saint Louis encephalitis viruses, so genetic-based control efforts for this species could also have a direct impact on human health. This commentary will discuss the current state of development and future needs for genetic-based technologies in lesser studied, but important disease vectors, such as C. quinquefasciatus, and make comparisons to technologies available in more studied vectors. While most current genetic control focuses on human disease, we will address the impact that these technologies could have on both disease and conservation focused vector control efforts and what is needed to prepare these technologies for evaluation in the field. The versatility of genetic-based technologies may result in the development of many important tools to control a variety of vectors that impact human, animal, and ecosystem health.
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3
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Miranda Paez A, Chalkowski K, Zohdy S, Willoughby JR. Management of avian malaria in populations of high conservation concern. Parasit Vectors 2022; 15:208. [PMID: 35705963 PMCID: PMC9199230 DOI: 10.1186/s13071-022-05327-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Accepted: 05/18/2022] [Indexed: 12/04/2022] Open
Abstract
Avian malaria is a vector-borne disease that is caused by Plasmodium parasites. These parasites are transmitted via mosquito bites and can cause sickness or death in a wide variety of birds, including many threatened and endangered species. This Primer first provides contextual background for the avian malaria system including the life cycle, geographic distribution and spread. Then, we focus on recent advances in understanding avian malaria ecology, including how avian malaria can lead to large ecosystem changes and variation in host immune responses to Plasmodium infection. Finally, we review advances in avian malaria management in vulnerable bird populations including genetic modification methods suitable for limiting the effects of this disease in wild populations and the use of sterile insect techniques to reduce vector abundance.
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Affiliation(s)
- Andrea Miranda Paez
- College of Forestry, Wildlife and Environment, Auburn University, Auburn, AL, USA.
| | - Kayleigh Chalkowski
- College of Forestry, Wildlife and Environment, Auburn University, Auburn, AL, USA
| | - Sarah Zohdy
- College of Forestry, Wildlife and Environment and College of Veterinary Medicine, Auburn University, Auburn, AL, USA
| | - Janna R Willoughby
- College of Forestry, Wildlife and Environment, Auburn University, Auburn, AL, USA
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4
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Sharma A, Pham MN, Reyes JB, Chana R, Yim WC, Heu CC, Kim D, Chaverra-Rodriguez D, Rasgon JL, Harrell RA, Nuss AB, Gulia-Nuss M. Cas9-mediated gene editing in the black-legged tick, Ixodes scapularis, by embryo injection and ReMOT Control. iScience 2022; 25:103781. [PMID: 35535206 PMCID: PMC9076890 DOI: 10.1016/j.isci.2022.103781] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 11/30/2021] [Accepted: 01/11/2022] [Indexed: 11/04/2022] Open
Abstract
Despite their capacity to acquire and pass on an array of debilitating pathogens, research on ticks has lagged behind other arthropod vectors, such as mosquitoes, largely because of challenges in applying available genetic and molecular tools. CRISPR-Cas9 is transforming non-model organism research; however, successful gene editing has not yet been reported in ticks. Technical challenges for injecting tick embryos to attempt gene editing have further slowed research progress. Currently, no embryo injection protocol exists for any chelicerate species, including ticks. Herein, we report a successful embryo injection protocol for the black-legged tick, Ixodes scapularis, and the use of this protocol for genome editing with CRISPR-Cas9. We also demonstrate that the ReMOT Control technique could be successfully used to generate genome mutations outside Insecta. Our results provide innovative tools to the tick research community that are essential for advancing our understanding of the molecular mechanisms governing pathogen transmission by tick vectors and the underlying biology of host-vector-pathogen interactions.
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Affiliation(s)
- Arvind Sharma
- Department of Biochemistry and Molecular Biology, University of Nevada, Reno, NV 89557, USA
| | - Michael N. Pham
- Department of Biochemistry and Molecular Biology, University of Nevada, Reno, NV 89557, USA
| | - Jeremiah B. Reyes
- Department of Biochemistry and Molecular Biology, University of Nevada, Reno, NV 89557, USA
| | - Randeep Chana
- Department of Biochemistry and Molecular Biology, University of Nevada, Reno, NV 89557, USA
| | - Won C. Yim
- Department of Biochemistry and Molecular Biology, University of Nevada, Reno, NV 89557, USA
| | - Chan C. Heu
- Department of Entomology, The Center for Infectious Disease Dynamics, and the Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA 16802, USA
| | - Donghun Kim
- Department of Entomology, The Center for Infectious Disease Dynamics, and the Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA 16802, USA
| | - Duverney Chaverra-Rodriguez
- Department of Entomology, The Center for Infectious Disease Dynamics, and the Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA 16802, USA
| | - Jason L. Rasgon
- Department of Entomology, The Center for Infectious Disease Dynamics, and the Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA 16802, USA
| | - Robert A. Harrell
- Insect Transformation Facility, University of Maryland Institute for Bioscience and Biotechnology Research, Rockville, MD 20850, USA
| | - Andrew B. Nuss
- Department of Biochemistry and Molecular Biology, University of Nevada, Reno, NV 89557, USA
- Department of Agriculture, Veterinary and Rangeland Sciences, University of Nevada, Reno, NV 89557, USA
| | - Monika Gulia-Nuss
- Department of Biochemistry and Molecular Biology, University of Nevada, Reno, NV 89557, USA
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Heryanto C, Hanly JJ, Mazo-Vargas A, Tendolkar A, Martin A. Mapping and CRISPR homology-directed repair of a recessive white eye mutation in Plodia moths. iScience 2022; 25:103885. [PMID: 35243245 PMCID: PMC8861637 DOI: 10.1016/j.isci.2022.103885] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 12/23/2021] [Accepted: 01/11/2022] [Indexed: 11/29/2022] Open
Abstract
The pantry moth Plodia interpunctella is a worldwide pest of stored food products and a promising laboratory model system for lepidopteran functional genomics. Here we describe efficient methods for precise genome editing in this insect. A spontaneous recessive white-eyed phenotype maps to a frameshift deletion (c.737delC) in the white gene. CRISPR NHEJ mutagenesis of white replicates this phenotype with high rates of somatic biallelic knockout. G0 individuals with mutant clones on both eyes produced 100% mutant progeny, making white an ideal marker for co-conversion when targeting other genes. CRISPR HDR experiments corrected c.737delC and reverted white eyes to a pigmented state in 37% of G0 mosaic adults. These repaired alleles showed practical rates of germline transmission in backcrosses, demonstrating the potential of the technique for precise genome editing. Plodia offers a promising avenue for research in this taxon because of its lab-ready features, egg injectability, and editability. Plodia pantry moths are an emerging model organism for functional genomics in Lepidoptera Spontaneous and CRISPR-induced white mutations yield recessive-white eye phenotypes CRISPR HDR repair with ssODN donor result in practical rates of base editing We provide optimized protocols for Plodia handling and genome editing
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Abstract
CRISPR-mediated genome engineering technologies have been adapted to a wide variety of organisms with high efficiency and specificity. The yellow fever mosquito, Aedes aegypti , is one such organism. It is also responsible for transmitting a wide variety of deadly viruses including Dengue, Zika, Yellow fever, and Chikungunya. The key to successful CRISPR-mediated gene editing applications is the delivery of both Cas9 ribonuclease and single-guide RNA (sgRNA ) to the nucleus of desired cells. Various methods have been developed for supplying the Cas9 endonuclease, sgRNA , and donor DNA to Ae. aegypti. In this chapter, we focus on methods of direct embryo delivery of editing components, presenting detailed step-by-step CRISPR/Cas9-based genome-editing protocols for inducing desired heritable edits in mosquitoes as well as insights into successful application of these protocols. We also highlight potential opportunities for customizing these protocols to manipulate the mosquito genome for innovative in vivo gene function studies.
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Affiliation(s)
- Ruichen Sun
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California San Diego, La Jolla, CA, USA
| | - Ming Li
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California San Diego, La Jolla, CA, USA
| | - Conor J McMeniman
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Johns Hopkins Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Omar S Akbari
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California San Diego, La Jolla, CA, USA.
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7
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Feng X, Kambic L, Nishimoto JH, Reed FA, Denton JA, Sutton JT, Gantz VM. Evaluation of Gene Knockouts by CRISPR as Potential Targets for the Genetic Engineering of the Mosquito Culex quinquefasciatus. CRISPR J 2021; 4:595-608. [PMID: 34280034 PMCID: PMC8392076 DOI: 10.1089/crispr.2021.0028] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Culex quinquefasciatus mosquitoes are a globally widespread vector of several human and animal pathogens. Their biology and behavior allow them to thrive in proximity to urban areas, rendering them a constant public health threat. Their mixed bird/mammal feeding behavior further offers a vehicle for zoonotic pathogens transmission to people and, separately, poses a threat to the conservation of insular birds. The advent of CRISPR has led to the development of novel technologies for the genetic engineering of wild mosquito populations. Yet, research into Cx. quinquefasciatus has been lagging compared to other disease vectors. Here, we use this tool to disrupt a set of five pigmentation genes in Cx. quinquefasciatus that, when altered, lead to visible, homozygous-viable phenotypes. We further validate this approach in separate laboratories and in two distinct strains of Cx. quinquefasciatus that are relevant to potential future public health and bird conservation applications. We generate a double-mutant line, demonstrating the possibility of sequentially combining multiple such mutations in a single individual. Lastly, we target two loci, doublesex in the sex-determination pathway and proboscipedia, a hox gene, demonstrating the flexibility of these methods applied to novel targets. Our work provides a platform of seven validated loci that could be used for targeted mutagenesis in Cx. quinquefasciatus and the future development of genetic suppression strategies for this species. Furthermore, the mutant lines generated here could have widespread utility to the research community using this model organism, as they could be used as targets for transgene delivery, where a copy of the disrupted gene could be included as an easily scored transgenesis marker.
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Affiliation(s)
- Xuechun Feng
- Section of Cell and Developmental Biology, University of California San Diego, La Jolla, California, USA
| | - Lukas Kambic
- Department of Biology, University of Hawaiʻi at Hilo, Hilo, Hawaiʻi, USA
| | | | - Floyd A. Reed
- School of Life Sciences, University of Hawaiʻi at Mānoa, Honolulu, Hawai‘i, USA
| | - Jai A. Denton
- Institute of Vector-borne Disease, University of Monash, Clayton, Australia
| | - Jolene T. Sutton
- Department of Biology, University of Hawaiʻi at Hilo, Hilo, Hawaiʻi, USA
| | - Valentino M. Gantz
- Section of Cell and Developmental Biology, University of California San Diego, La Jolla, California, USA
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8
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Purusothaman DK, Shackleford L, Anderson MAE, Harvey-Samuel T, Alphey L. CRISPR/Cas-9 mediated knock-in by homology dependent repair in the West Nile Virus vector Culex quinquefasciatus Say. Sci Rep 2021; 11:14964. [PMID: 34294769 PMCID: PMC8298393 DOI: 10.1038/s41598-021-94065-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Accepted: 06/28/2021] [Indexed: 11/27/2022] Open
Abstract
Culex quinquefasciatus Say is a mosquito distributed in both tropical and subtropical regions of the world. It is a night-active, opportunistic blood-feeder and vectors many animal and human diseases, including West Nile Virus and avian malaria. Current vector control methods (e.g. physical/chemical) are increasingly ineffective; use of insecticides also imposes hazards to both human and ecosystem health. Advances in genome editing have allowed the development of genetic insect control methods, which are species-specific and, theoretically, highly effective. CRISPR/Cas9 is a bacteria-derived programmable gene editing tool that is functional in a range of species. We describe the first successful germline gene knock-in by homology dependent repair in C. quinquefasciatus. Using CRISPR/Cas9, we integrated an sgRNA expression cassette and marker gene encoding a fluorescent protein fluorophore (Hr5/IE1-DsRed, Cq7SK-sgRNA) into the kynurenine 3-monooxygenase (kmo) gene. We achieved a minimum transformation rate of 2.8%, similar to rates in other mosquito species. Precise knock-in at the intended locus was confirmed. Insertion homozygotes displayed a white eye phenotype in early-mid larvae and a recessive lethal phenotype by pupation. This work provides an efficient method for engineering C. quinquefasciatus, providing a new tool for developing genetic control tools for this vector.
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Affiliation(s)
| | - Lewis Shackleford
- Arthropod Genetics, The Pirbright Institute, Ash Road, Pirbright, GU24 0NF, Surrey, UK
| | - Michelle A E Anderson
- Arthropod Genetics, The Pirbright Institute, Ash Road, Pirbright, GU24 0NF, Surrey, UK
| | - Tim Harvey-Samuel
- Arthropod Genetics, The Pirbright Institute, Ash Road, Pirbright, GU24 0NF, Surrey, UK
| | - Luke Alphey
- Arthropod Genetics, The Pirbright Institute, Ash Road, Pirbright, GU24 0NF, Surrey, UK.
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9
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Feng X, López Del Amo V, Mameli E, Lee M, Bishop AL, Perrimon N, Gantz VM. Optimized CRISPR tools and site-directed transgenesis towards gene drive development in Culex quinquefasciatus mosquitoes. Nat Commun 2021; 12:2960. [PMID: 34017003 PMCID: PMC8137705 DOI: 10.1038/s41467-021-23239-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Accepted: 04/21/2021] [Indexed: 12/15/2022] Open
Abstract
Culex mosquitoes are a global vector for multiple human and animal diseases, including West Nile virus, lymphatic filariasis, and avian malaria, posing a constant threat to public health, livestock, companion animals, and endangered birds. While rising insecticide resistance has threatened the control of Culex mosquitoes, advances in CRISPR genome-editing tools have fostered the development of alternative genetic strategies such as gene drive systems to fight disease vectors. However, though gene-drive technology has quickly progressed in other mosquitoes, advances have been lacking in Culex. Here, we develop a Culex-specific Cas9/gRNA expression toolkit and use site-directed homology-based transgenesis to generate and validate a Culex quinquefasciatus Cas9-expressing line. We show that gRNA scaffold variants improve transgenesis efficiency in both Culex quinquefasciatus and Drosophila melanogaster and boost gene-drive performance in the fruit fly. These findings support future technology development to control Culex mosquitoes and provide valuable insight for improving these tools in other species.
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Affiliation(s)
- Xuechun Feng
- Section of Cell and Developmental Biology, University of California San Diego, La Jolla, CA, USA
| | - Víctor López Del Amo
- Section of Cell and Developmental Biology, University of California San Diego, La Jolla, CA, USA
| | - Enzo Mameli
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
- Department of Microbiology, National Emerging Infectious Diseases Laboratories, Boston University, School of Medicine, Boston, MA, USA
| | - Megan Lee
- Section of Cell and Developmental Biology, University of California San Diego, La Jolla, CA, USA
| | - Alena L Bishop
- Section of Cell and Developmental Biology, University of California San Diego, La Jolla, CA, USA
| | - Norbert Perrimon
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
- HHMI, Harvard Medical School, Boston, MA, USA
| | - Valentino M Gantz
- Section of Cell and Developmental Biology, University of California San Diego, La Jolla, CA, USA.
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10
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Trivedi D. Using CRISPR-Cas9-based genome engineering tools in Drosophila melanogaster. Prog Mol Biol Transl Sci 2021; 180:85-121. [PMID: 33934839 DOI: 10.1016/bs.pmbts.2021.01.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Drosophila melanogaster has been used as a model organism for over a century. Mutant-based analyses have been used extensively to understand the genetic basis of different cellular processes, including development, neuronal function and diseases. Most of the earlier genetic mutants and specific tools were generated by random insertions and deletion strategies and then mapped to specific genomic loci. Since all genomic regions are not equally accessible to random mutations and insertions, many genes still remain uncharacterized. Low efficiency of targeted genomic manipulation approaches that rely on homologous recombination, and difficulty in generating resources for sequence-specific endonucleases, such as ZFNs (Zinc Finger Nucleases) and TALENs (Transcription Activator-Like Effector Nucleases), could not make these gene targeting techniques very popular. However, recently RNA directed DNA endonucleases, such as CRISPR-Cas, have transformed genome engineering owing to their comparative ease, versatility, and low expense. With the added advantage of preexisting genetic tools, CRISPR-Cas-based manipulations are being extensively used in Drosophila melanogaster and simultaneously being fine-tuned for specific experimental requirements. In this chapter, I will discuss various uses of CRISPR-Cas-based genetic engineering and specific design methods in Drosophila melanogaster. I will summarize various already available tools that are being utilized in conjunction with CRISPR-Cas technology to generate specific genetic manipulation and are being optimized to address specific questions. Finally, I will discuss the future directions of Drosophila genetics research and how CRISPR-Cas can be utilized to target specific questions, addressing which has not been possible thus far.
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Affiliation(s)
- Deepti Trivedi
- National Centre for Biological Sciences-TIFR, Bengaluru, India.
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11
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Navarro-Payá D, Flis I, Anderson MAE, Hawes P, Li M, Akbari OS, Basu S, Alphey L. Targeting female flight for genetic control of mosquitoes. PLoS Negl Trop Dis 2020; 14:e0008876. [PMID: 33270627 PMCID: PMC7714197 DOI: 10.1371/journal.pntd.0008876] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Accepted: 10/12/2020] [Indexed: 01/04/2023] Open
Abstract
Aedes aegypti Act4 is a paralog of the Drosophila melanogaster indirect flight muscle actin gene Act88F. Act88F has been shown to be haploinsufficient for flight in both males and females (amorphic mutants are dominant). Whereas Act88F is expressed in indirect flight muscles of both males and females, expression of Act4 is substantially female-specific. We therefore used CRISPR/Cas9 and homology directed repair to examine the phenotype of Act4 mutants in two Culicine mosquitoes, Aedes aegypti and Culex quinquefasciatus. A screen for dominant female-flightless mutants in Cx. quinquefasciatus identified one such mutant associated with a six base pair deletion in the CxAct4 coding region. A similar screen in Ae. aegypti identified no dominant mutants. Disruption of the AeAct4 gene by homology-dependent insertion of a fluorescent protein marker cassette gave a recessive female-flightless phenotype in Ae. aegypti. Reproducing the six-base deletion from Cx. quinquefasciatus in Ae. aegypti using oligo-directed mutagenesis generated dominant female-flightless mutants and identified additional dominant female-flightless mutants with other in-frame insertions or deletions. Our data indicate that loss of function mutations in the AeAct4 gene are recessive but that short in-frame deletions produce dominant-negative versions of the AeAct4 protein that interfere with flight muscle function. This makes Act4 an interesting candidate for genetic control methods, particularly population-suppression gene drives targeting female viability/fertility.
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Affiliation(s)
| | - Ilona Flis
- Arthropod Genetics, The Pirbright Institute, Pirbright, United Kingdom
| | | | - Philippa Hawes
- Bioimaging, The Pirbright Institute, Pirbright, United Kingdom
| | - Ming Li
- Cell and Developmental Biology Section, Division of Biological Sciences, University of California, San Diego, California, United States of America
| | - Omar S. Akbari
- Cell and Developmental Biology Section, Division of Biological Sciences, University of California, San Diego, California, United States of America
| | - Sanjay Basu
- Arthropod Genetics, The Pirbright Institute, Pirbright, United Kingdom
| | - Luke Alphey
- Arthropod Genetics, The Pirbright Institute, Pirbright, United Kingdom
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12
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Smith RC. Highlights in Medical Entomology, 2019: Familiar Foes and New Frontiers. J Med Entomol 2020; 57:1349-1353. [PMID: 32667035 PMCID: PMC7716807 DOI: 10.1093/jme/tjaa120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Indexed: 06/11/2023]
Abstract
The 2019 Entomological Society of America annual meeting was held in St. Louis, Missouri, just blocks away from the iconic Gateway Arch. Representing a 'gateway to the West', this inspired the theme of the Highlights in Medical Entomology to reflect on the accomplishments of the past year as we move into a 'new frontier' of vector biology research. Papers were selected broadly across arthropods that influence public health, focusing on topics ranging from West Nile virus transmission, ticks and tick-borne disease, to advances in genetics and 'big data' studies. This included current perspectives on West Nile virus ecology and epidemiology, which has now been endemic in the United States for 20 yr. Additional topics such as the advantages of citizen science and the importance of scientific communication were also discussed. Together, these papers demonstrate the achievements of the vector community while emphasizing the challenges that we collectively face to reduce the burden of vector-borne disease.
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Affiliation(s)
- Ryan C Smith
- Department of Entomology, Iowa State University, Ames, IA
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13
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Wiltshire RM, Duman-Scheel M. Advances in oral RNAi for disease vector mosquito research and control. Curr Opin Insect Sci 2020; 40:18-23. [PMID: 32516723 PMCID: PMC8718359 DOI: 10.1016/j.cois.2020.05.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Revised: 03/02/2020] [Accepted: 05/04/2020] [Indexed: 05/11/2023]
Abstract
Mosquito vectors in the genera Anopheles, Aedes, and Culex transmit a variety of medically important pathogens. Current vector control tools are reaching the limits of their effectiveness, necessitating the introduction of innovative vector control technologies. RNAi, which facilitates functional characterization of mosquito genes in the laboratory, could one day be applied as a new method of vector control. Recent advances in the oral administration of microbial-based systems for delivery of species-specific interfering RNA pesticides to mosquitoes may facilitate translation of this technology to the field. Oral RNAi-based pesticides represent a new class of biorational pesticides that could combat increased global incidence of insecticide resistance and which could one day become critical components of integrated human disease vector mosquito control programs.
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Affiliation(s)
- Rachel M Wiltshire
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, 1234 N. Notre Dame Ave, South Bend, IN 46617, USA; Eck Institute for Global Health, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Molly Duman-Scheel
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, 1234 N. Notre Dame Ave, South Bend, IN 46617, USA; Eck Institute for Global Health, University of Notre Dame, Notre Dame, IN 46556, USA; Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, USA.
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14
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Anderson ME, Mavica J, Shackleford L, Flis I, Fochler S, Basu S, Alphey L. CRISPR/Cas9 gene editing in the West Nile Virus vector, Culex quinquefasciatus Say. PLoS One 2019; 14:e0224857. [PMID: 31714905 PMCID: PMC6850532 DOI: 10.1371/journal.pone.0224857] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Accepted: 10/23/2019] [Indexed: 12/16/2022] Open
Abstract
Culex quinquefasciatus Say is an opportunistic blood feeder with a wide geographic distribution which is also a major vector for a range of diseases of both animals and humans. CRISPR/Cas technologies have been applied to a wide variety of organisms for both applied and basic research purposes. CRISPR/Cas methods open new possibilities for genetic research in non-model organisms of public health importance. In this work we have adapted microinjection techniques commonly used in other mosquito species to Culex quinquefasciatus, and have shown these to be effective at generating homozygous knock-out mutations of a target gene in one generation. This is the first description of the kmo gene and mutant phenotype in this species.
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Affiliation(s)
- Michelle E. Anderson
- Arthropod Genetics, The Pirbright Institute, Pirbright, Woking, England, United Kingdom
| | - Jessica Mavica
- Arthropod Genetics, The Pirbright Institute, Pirbright, Woking, England, United Kingdom
| | - Lewis Shackleford
- Arthropod Genetics, The Pirbright Institute, Pirbright, Woking, England, United Kingdom
| | - Ilona Flis
- Arthropod Genetics, The Pirbright Institute, Pirbright, Woking, England, United Kingdom
| | - Sophia Fochler
- Arthropod Genetics, The Pirbright Institute, Pirbright, Woking, England, United Kingdom
| | - Sanjay Basu
- Arthropod Genetics, The Pirbright Institute, Pirbright, Woking, England, United Kingdom
| | - Luke Alphey
- Arthropod Genetics, The Pirbright Institute, Pirbright, Woking, England, United Kingdom
- * E-mail:
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