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Sharma A, Kinney NA, Timoshevskiy VA, Sharakhova MV, Sharakhov IV. Structural Variation of the X Chromosome Heterochromatin in the Anopheles gambiae Complex. Genes (Basel) 2020; 11:E327. [PMID: 32204543 PMCID: PMC7140835 DOI: 10.3390/genes11030327] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 03/13/2020] [Accepted: 03/16/2020] [Indexed: 12/31/2022] Open
Abstract
Heterochromatin is identified as a potential factor driving diversification of species. To understand the magnitude of heterochromatin variation within the Anopheles gambiae complex of malaria mosquitoes, we analyzed metaphase chromosomes in An. arabiensis, An. coluzzii, An. gambiae, An. merus, and An. quadriannulatus. Using fluorescence in situ hybridization (FISH) with ribosomal DNA (rDNA), a highly repetitive fraction of DNA, and heterochromatic Bacterial Artificial Chromosome (BAC) clones, we established the correspondence of pericentric heterochromatin between the metaphase and polytene X chromosomes of An. gambiae. We then developed chromosome idiograms and demonstrated that the X chromosomes exhibit qualitative differences in their pattern of heterochromatic bands and position of satellite DNA (satDNA) repeats among the sibling species with postzygotic isolation, An. arabiensis, An. merus, An. quadriannulatus, and An. coluzzii or An. gambiae. The identified differences in the size and structure of the X chromosome heterochromatin point to a possible role of repetitive DNA in speciation of mosquitoes. We found that An. coluzzii and An. gambiae, incipient species with prezygotic isolation, share variations in the relative positions of the satDNA repeats and the proximal heterochromatin band on the X chromosomes. This previously unknown genetic polymorphism in malaria mosquitoes may be caused by a differential amplification of DNA repeats or an inversion in the sex chromosome heterochromatin.
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Affiliation(s)
- Atashi Sharma
- Department of Entomology, Virginia Polytechnic and State University, Blacksburg, VA 24061, USA; (A.S.); (V.A.T.); (M.V.S.)
| | - Nicholas A. Kinney
- Genomics Bioinformatics and Computational Biology, Virginia Polytechnic and State University, Blacksburg, VA 24061, USA;
| | - Vladimir A. Timoshevskiy
- Department of Entomology, Virginia Polytechnic and State University, Blacksburg, VA 24061, USA; (A.S.); (V.A.T.); (M.V.S.)
| | - Maria V. Sharakhova
- Department of Entomology, Virginia Polytechnic and State University, Blacksburg, VA 24061, USA; (A.S.); (V.A.T.); (M.V.S.)
- Laboratory of Evolutionary Genomics of Insects, the Federal Research Center Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia
- Laboratory of Ecology, Genetics and Environmental Protection, Tomsk State University, 634050 Tomsk, Russia
| | - Igor V. Sharakhov
- Department of Entomology, Virginia Polytechnic and State University, Blacksburg, VA 24061, USA; (A.S.); (V.A.T.); (M.V.S.)
- Genomics Bioinformatics and Computational Biology, Virginia Polytechnic and State University, Blacksburg, VA 24061, USA;
- Laboratory of Evolutionary Genomics of Insects, the Federal Research Center Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia
- Department of Cytology and Genetics, Tomsk State University, 634050 Tomsk, Russia
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Chemical constituents of thermal stress induced Ganoderma applantum (Per.) secondary metabolites on larvae of Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus and histopathological effects in mosquito larvae. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2019. [DOI: 10.1016/j.bcab.2019.101253] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Wilke ABB, Marrelli MT. Paratransgenesis: a promising new strategy for mosquito vector control. Parasit Vectors 2015; 8:342. [PMID: 26104575 PMCID: PMC4489152 DOI: 10.1186/s13071-015-0959-2] [Citation(s) in RCA: 100] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Accepted: 06/17/2015] [Indexed: 11/23/2022] Open
Abstract
The three main mosquito genera, Anopheles, Aedes and Culex, transmit respectively malaria, dengue and lymphatic filariasis. Current mosquito control strategies have proved unsuccessful, and there still is a substantial number of morbidity and mortality from these diseases. Genetic control methods have now arisen as promising alternative strategies, based on two approaches: the replacement of a vector population by disease-refractory mosquitoes and the release of mosquitoes carrying a lethal gene to suppress target populations. However, substantial hurdles and limitations need to be overcome if these methods are to be used successfully, the most significant being that a transgenic mosquito strain is required for every target species, making genetically modified mosquito strategies inviable when there are multiple vector mosquitoes in the same area. Genetically modified bacteria capable of colonizing a wide range of mosquito species may be a solution to this problem and another option for the control of these diseases. In the paratransgenic approach, symbiotic bacteria are genetically modified and reintroduced in mosquitoes, where they express effector molecules. For this approach to be used in practice, however, requires a better understanding of mosquito microbiota and that symbiotic bacteria and effector molecules be identified. Paratransgenesis could prove very useful in mosquito species that are inherently difficult to transform or in sibling species complexes. In this approach, a genetic modified bacteria can act by: (a) causing pathogenic effects in the host; (b) interfering with the host's reproduction; (c) reducing the vector's competence; and (d) interfering with oogenesis and embryogenesis. It is a much more flexible and adaptable approach than the use of genetically modified mosquitoes because effector molecules and symbiotic bacteria can be replaced if they do not achieve the desired result. Paratransgenesis may therefore become an important integrated pest management tool for mosquito control.
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Affiliation(s)
- André Barretto Bruno Wilke
- Departamento de Epidemiologia, Faculdade de Saúde Pública, Universidade de São Paulo, Av. Dr. Arnaldo 715, São Paulo, SP, CEP-01246-904, Brazil.
| | - Mauro Toledo Marrelli
- Departamento de Epidemiologia, Faculdade de Saúde Pública, Universidade de São Paulo, Av. Dr. Arnaldo 715, São Paulo, SP, CEP-01246-904, Brazil.
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Wilke ABB, Marrelli MT. Genetic Control of Mosquitoes: population suppression strategies. Rev Inst Med Trop Sao Paulo 2012; 54:287-92. [DOI: 10.1590/s0036-46652012000500009] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2011] [Accepted: 05/17/2012] [Indexed: 11/21/2022] Open
Abstract
Over the last two decades, morbidity and mortality from malaria and dengue fever among other pathogens are an increasing Public Health problem. The increase in the geographic distribution of vectors is accompanied by the emergence of viruses and diseases in new areas. There are insufficient specific therapeutic drugs available and there are no reliable vaccines for malaria or dengue, although some progress has been achieved, there is still a long way between its development and actual field use. Most mosquito control measures have failed to achieve their goals, mostly because of the mosquito's great reproductive capacity and genomic flexibility. Chemical control is increasingly restricted due to potential human toxicity, mortality in no target organisms, insecticide resistance, and other environmental impacts. Other strategies for mosquito control are desperately needed. The Sterile Insect Technique (SIT) is a species-specific and environmentally benign method for insect population suppression, it is based on mass rearing, radiation mediated sterilization, and release of a large number of male insects. Releasing of Insects carrying a dominant lethal gene (RIDL) offers a solution to many of the drawbacks of traditional SIT that have limited its application in mosquitoes while maintaining its environmentally friendly and species-specific utility. The self-limiting nature of sterile mosquitoes tends to make the issues related to field use of these somewhat less challenging than for self-spreading systems characteristic of population replacement strategies. They also are closer to field use, so might be appropriate to consider first. The prospect of genetic control methods against mosquito vectored human diseases is rapidly becoming a reality, many decisions will need to be made on a national, regional and international level regarding the biosafety, social, cultural and ethical aspects of the use and deployment of these vector control methods.
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Wilke ABB, Gomes ADC, Natal D, Marrelli MT. Controle de vetores utilizando mosquitos geneticamente modificados. Rev Saude Publica 2009; 43:869-74. [PMID: 19722003 DOI: 10.1590/s0034-89102009005000050] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2008] [Accepted: 01/28/2009] [Indexed: 11/21/2022] Open
Abstract
Formas químicas de controle de mosquitos vetores são ineficazes, levando ao desenvolvimento de novas estratégias. Assim, foi realizada revisão das estratégias de controle genético de populações de mosquitos vetores baseada na técnica do inseto estéril. Uma delas consiste na liberação de machos esterilizados por radiação, a outra, na integração de um gene letal dominante associado a um promotor específico de fêmeas imaturas. Entre as vantagens sobre outras técnicas biológicas e químicas de controle de vetores estão: alta especificidade, não prejudicial ao meio ambiente, baixo custo de produção e alta eficácia. O uso desta técnica de modificação genética pode vir a ser uma importante ferramenta do manejo integrado de vetores.
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Mohanty A, Swain S, Kar SK, Hazra RK. Analysis of the phylogenetic relationship of Anopheles species, subgenus Cellia (Diptera: Culicidae) and using it to define the relationship of morphologically similar species. INFECTION GENETICS AND EVOLUTION 2009; 9:1204-24. [PMID: 19577013 DOI: 10.1016/j.meegid.2009.06.021] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2009] [Revised: 06/18/2009] [Accepted: 06/24/2009] [Indexed: 11/16/2022]
Abstract
Studies on the relationship of various vectors and non-vectors of malaria from the evolutionary point of view are important. Use of molecular methods to define phylogeny helps to understand the interrelationship among the members of the anophelines and elucidate the ambiguity that has arisen from improper classification. It could also help to design molecular markers for species differentiation, particularly in those which pose difficulty when classified, based on morphological features. In the present study, the phylogenetic relationships among the species of the anophelines of subgenus Cellia are inferred from the mitochondrial genes COI and COII, the ribosomal RNA gene, in particular the D3 region, and Internal Transcribed Spacer 2 (ITS2) region. The molecular phylogeny obtained in this work matches with that of the classical morphological taxonomy reasonably well, and was useful in properly defining species positions and resolving the ambiguity that normally arises due to morphological taxonomy. The correct arrangement of the various anopheline taxa as per the traditional morphological character-based classification of anophelines was there when we considered the D3 region of 28S rRNA gene and ITS2 region of rDNA. However, the arrangement of the taxa did not match with that of the morphological classification in some aspects, when we considered the COI and COII region of mitochondrial DNA. It may have been due to the variable degree of the rate of evolution of the different genes within the organism. Thus, a proper selection of those particular genes that evolve at the rate that is reflected at the species differentiation level, could help to construct the correct phylogenetic relationship among the anophelines and could be used to correlate with the grouping pattern done from the morphological perspective.
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Affiliation(s)
- Amitav Mohanty
- Division of Vector Borne Diseases, Institute of Life Sciences, Bhubaneswar, India
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7
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Abstract
A great deal of information has been accumulated on chromosome numbers and heterochromatin distribution as well as on genome size and organization in the mosquito family Culicidae. A number of trends in genome evolution emerge when these data are reviewed in light of recent cladistic phylogenies of Culicidae and its sister families. Anophelinae have heteromorphic sex chromosomes and a small genome size, and repetitive elements are distributed in a long-period interspersion pattern. In contrast, Culicinae have homomorphic sex chromosomes, and repetitive DNA is organized in a short-period interspersion pattern. There has been a general increase in genome size during the evolution of culicine tribes. The organization of the ancestral culicid genome remains uncertain awaiting studies on genome organization in Chaoboridae-Corethrellidae taxa. The most parsimonious hypothesis for the evolution of sex chromosomes and genome organization in Culicidae would be that homomorphic sex chromosomes and a long-period interspersion pattern was ancestral in lineages leading to Toxorhynchitinae and Culcinae. Larger genomes developed in subsequent culicine lineages through accumulation of short-period interspersed repetitive elements. Heteromorphic sex chromosomes evolved early in the evolution of Anophelinae, and a long-period interspersion pattern was retained. The alternative scenario proposed by Rao and Rai (1987a) is that Culicidae arose from a chaoborid Mochlonyx-like ancestor with heteromorphic sex chromosomes and possibly short-period interspersion. This scenario would require the loss of heteromorphic sex chromosomes in the lineage leading to Toxorhynchitinae and Culicinae and the "shedding" of repetitive elements in the lineage leading to Anophelinae. Several interesting patterns have emerged from studies of C-banding, and the distribution of heterochromatin in Culicidae and phylogenies derived from these studies are supported by the modern cladistic analyses. Recent intensive multipoint linkage map studies suggest that recombination frequencies per genome have remained relatively constant over the course of culicid evolution such that Anophelinae, with a relatively small genome size, has a linkage map of similar size to Aedini. As a consequence, taxa in Anophelinae have higher amounts of recombination per haploid genome size than Culicinae. Although several key questions have yet to be addressed, the Culicidae remain one of the best-studied systems of genome evolution in animals.
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Affiliation(s)
- K S Rai
- Department of Biological Sciences, University of Notre Dame, Indiana 46556, USA.
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Severson DW, Brown SE, Knudson DL. Genetic and physical mapping in mosquitoes: molecular approaches. ANNUAL REVIEW OF ENTOMOLOGY 2001; 46:183-219. [PMID: 11112168 DOI: 10.1146/annurev.ento.46.1.183] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The genetic background of individual mosquito species and populations within those species influences the transmission of mosquito-borne pathogens to humans. Technical advances in contemporary genomics are contributing significantly to the detailed genetic analysis of this mosquito-pathogen interaction as well as all other aspects of mosquito biology, ecology, and evolution. A variety of DNA-based marker types are being used to develop genetic maps for a number of mosquito species. Complex phenotypic traits such as vector competence are being dissected into their discrete genetic components, with the intention of eventually using this information to develop new methods to prevent disease transmission. Both genetic- and physical-mapping techniques are being used to define and compare genome architecture among and within mosquito species. The integration of genetic- and physical-map information is providing a sound framework for map-based positional cloning of target genes of interest. This review focuses on advances in genome-based analysis and their specific applications to mosquitoes.
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Affiliation(s)
- D W Severson
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana 46556, USA.
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Shouche YS, Patole MS. Sequence analysis of mitochondrial 16S ribosomal RNA gene fragment from seven mosquito species. J Biosci 2000; 25:361-6. [PMID: 11120588 DOI: 10.1007/bf02703789] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Mosquitoes are vectors for the transmission of many human pathogens that include viruses, nematodes and protozoa. For the understanding of their vectorial capacity, identification of disease carrying and refractory strains is essential. Recently, molecular taxonomic techniques have been utilized for this purpose. Sequence analysis of the mitochondrial 16S rRNA gene has been used for molecular taxonomy in many insects. In this paper, we have analysed a 450 bp hypervariable region of the mitochondrial 16S rRNA gene in three major genera of mosquitoes, Aedes, Anopheles and Culex. The sequence was found to be unusually A+T rich and in substitutions the rate of transversions was higher than the transition rate. A phylogenetic tree was constructed with these sequences. An interesting feature of the sequences was a stretch of Ts that distinguished between Ae-des and Culex on the one hand, and Anopheles on the other. This is the first report of mitochondrial rRNA sequences from these medically important genera of mosquitoes.
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Affiliation(s)
- Y S Shouche
- National Center for Cell Science, Pune University Campus, Pune 411 007, India.
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10
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Leitch AR. Higher levels of organization in the interphase nucleus of cycling and differentiated cells. Microbiol Mol Biol Rev 2000; 64:138-52. [PMID: 10704477 PMCID: PMC98989 DOI: 10.1128/mmbr.64.1.138-152.2000] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The review examines the structured organization of interphase nuclei using a range of examples from the plants, animals, and fungi. Nuclear organization is shown to be an important phenomenon in cell differentiation and development. The review commences by examining nuclei in dividing cells and shows that the organization patterns can be dynamic within the time frame of the cell cycle. When cells stop dividing, derived differentiated cells often show quite different nuclear organizations. The developmental fate of nuclei is divided into three categories. (i) The first includes nuclei that undergo one of several forms of polyploidy and can themselves change in structure during the course of development. Possible function roles of polyploidy is given. (ii) The second is nuclear reorganization without polyploidy, where nuclei reorganize their structure to form novel arrangements of proteins and chromosomes. (iii) The third is nuclear disintegration linked to programmed cell death. The role of the nucleus in this process is described. The review demonstrates that recent methods to probe nuclei for nucleic acids and proteins, as well as to examine their intranuclear distribution in vivo, has revealed much about nuclear structure. It is clear that nuclear organization can influence or be influenced by cell activity and development. However, the full functional role of many of the observed phenomena has still to be fully realized.
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Affiliation(s)
- A R Leitch
- Queen Mary and Westfield College, University of London, London, United Kingdom.
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Vinetz JM, Dave SK, Specht CA, Brameld KA, Xu B, Hayward R, Fidock DA. The chitinase PfCHT1 from the human malaria parasite Plasmodium falciparum lacks proenzyme and chitin-binding domains and displays unique substrate preferences. Proc Natl Acad Sci U S A 1999; 96:14061-6. [PMID: 10570198 PMCID: PMC24190 DOI: 10.1073/pnas.96.24.14061] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Within hours after the ingestion of a blood meal, the mosquito midgut epithelium synthesizes a chitinous sac, the peritrophic matrix. Plasmodium ookinetes traverse the peritrophic matrix while escaping the mosquito midgut. Chitinases (EC 3.2.1.14) are critical for parasite invasion of the midgut: the presence of the chitinase inhibitor, allosamidin, in an infectious blood meal prevents oocyst development. A chitinase gene, PgCHT1, recently has been identified in the avian malaria parasite P. gallinaceum. We used the sequence of PgCHT1 to identify a P. falciparum chitinase gene, PfCHT1, in the P. falciparum genome database. PfCHT1 differs from PgCHT1 in that the P. falciparum gene lacks proenzyme and chitin-binding domains. PfCHT1 was expressed as an active recombinant enzyme in Escherichia coli. PfCHT1 shares with PgCHT1 a substrate preference unique to Plasmodium chitinases: the enzymes cleave tri- and tetramers of GlcNAc from penta- and hexameric oligomers and are unable to cleave smaller native chitin oligosaccharides. The pH activity profile of PfCHT1 and its IC(50) (40 nM) to allosamidin are distinct from endochitinase activities secreted by P. gallinaceum ookinetes. Homology modeling predicts that PgCHT1 has a novel pocket in the catalytic active site that PfCHT1 lacks, which may explain the differential sensitivity of PfCHT1 and PgCHT1 to allosamidin. PfCHT1 may be the ortholog of a second, as yet unidentified, chitinase gene of P. gallinaceum. These results may allow us to develop novel strategies of blocking human malaria transmission based on interfering with P. falciparum chitinase.
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Affiliation(s)
- J M Vinetz
- WHO Center for Tropical Diseases, University of Texas Medical Branch, Galveston, TX 77555, USA.
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Tu Z. Three novel families of miniature inverted-repeat transposable elements are associated with genes of the yellow fever mosquito, Aedes aegypti. Proc Natl Acad Sci U S A 1997; 94:7475-80. [PMID: 9207116 PMCID: PMC23846 DOI: 10.1073/pnas.94.14.7475] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/1997] [Accepted: 05/12/1997] [Indexed: 02/04/2023] Open
Abstract
Three novel families of transposable elements, Wukong, Wujin, and Wuneng, are described in the yellow fever mosquito, Aedes aegypti. Their copy numbers range from 2,100 to 3,000 per haploid genome. There are high degrees of sequence similarity within each family, and many structural but not sequence similarities between families. The common structural characteristics include small size, no coding potential, terminal inverted repeats, potential to form a stable secondary structure, A+T richness, and putative 2- to 4-bp A+T-biased specific target sites. Evidence of previous mobility is presented for the Wukong elements. Elements of these three families are associated with 7 of 16 fully or partially sequenced Ae. aegypti genes. Characteristics of these mosquito elements indicate strong similarities to the miniature inverted-repeat transposable elements (MITEs) recently found to be associated with plant genes. MITE-like elements have also been reported in two species of Xenopus and in Homo sapiens. This characterization of multiple families of highly repetitive MITE-like elements in an invertebrate extends the range of these elements in eukaryotic genomes. A hypothesis is presented relating genome size and organization to the presence of highly reiterated MITE families. The association of MITE-like elements with Ae. aegypti genes shows the same bias toward noncoding regions as in plants. This association has potentially important implications for the evolution of gene regulation.
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Affiliation(s)
- Z Tu
- Department of Entomology and Center for Insect Science, University of Arizona, Tucson, AZ 85721, USA.
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Baldridge GD, Fallon AM. Evidence for a DNA homologous pairing activity in nuclear extracts from mosquito cells. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 1996; 26:667-676. [PMID: 8995789 DOI: 10.1016/s0965-1748(96)00017-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Using a sensitive homologous pairing/DNA strand transfer assay, we detected formation of joint molecules in the presence of nuclear extract from cultured mosquito C7-10 cells in a reaction containing single stranded circular m13 DNA and a linear, double stranded DNA 5'-end-labeled on the strand complementary to a portion of the single-stranded substrate. Joint molecules were detected by the reduced electrophoretic mobility of labeled probe on agarose gels, which indicated that the 5'-end labeled strand of the linear duplex had formed a hybrid with the single-stranded substrate. Characterization of the activity detected initially in crude nuclear extracts provided a basis for a 5-fold enrichment of activity after a two-step KCl elution from heparin-Sepharose. Further purification by preparative electrophoresis yielded a band at approximately 35 kDa, which, when transferred to Immobilon P membrane, specifically bound the labeled, complementary strand probe. Optimal activity of the electroeluted enzyme required both magnesium and ATP and was sensitive to the ratio of single-stranded and double-stranded DNA substrate and to the amount of protein. This homologous pairing activity from mosquito cells is the first such activity to be described from an insect other than Drosophila melanogaster.
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Affiliation(s)
- G D Baldridge
- Department of Entomology, University of Minnesota, St Paul 55108, USA
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Powers AM, Kamrud KI, Olson KE, Higgs S, Carlson JO, Beaty BJ. Molecularly engineered resistance to California serogroup virus replication in mosquito cells and mosquitoes. Proc Natl Acad Sci U S A 1996; 93:4187-91. [PMID: 8633038 PMCID: PMC39509 DOI: 10.1073/pnas.93.9.4187] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Introduction of genetic elements derived from a viral pathogen's genome may be used to reduce the vectorial capacity of mosquitoes for that virus. A double subgenomic Sindbis virus expression system was utilized to transcribe sequences of LaCrosse (LAC) virus small (S) or medium (M) segment RNA in sense or antisense orientation; wild-type Sindbis and LaCrosse viruses have single-stranded RNA genomes, the former being positive sense and the latter being negative sense. Recombinant viruses were generated and used to infect Aedes albopictus (C6/36) mosquito cells, which were challenged with wild-type LAC virus and then assayed for LAC virus replication. Several recombinant viruses containing portions of the LAC S segment were capable of inducing varying degrees of interference to the challenge virus. Cells infected with TE/3'2J/ANTI-S virus, expressing full-length negative-sense S RNA of LAC virus, yielded 3-6 log10TCID50 (tissue culture 50% infective dose) less LAC virus per ml than did cells infected with a double subgenomic sindbis virus containing no LAC insert. When C6/36 cells infected with TE/3'2J/ANTI-S were challenged with closely related heterologous bunyaviruses, a similar inhibitory effect was seen. Adult Ae. triseriatus mosquitoes infected with TE/3'2J/ANTI-S were also resistant to challenge by LAC virus. Organs that were productively infected by the double subgenomic Sindbis virus expressing the LAC anti-S sequences demonstrated little LAC virus or antigen. These studies indicate that expression of carefully selected antiviral sequences derived from the pathogen's genome may result in efficacious molecular viral interference in mosquito cells and, more importantly, in mosquitoes.
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Affiliation(s)
- A M Powers
- Department of Microbiology, Colorado State University, Ft. Collins 80523, USA
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Severson DW. Applications of molecular marker analysis to mosquito vector competence. ACTA ACUST UNITED AC 1994; 10:336-40. [PMID: 15275410 DOI: 10.1016/0169-4758(94)90243-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
A rapidly expanding cadre of molecular biology techniques is being developed for human and plant genetics, including development of the technology to identify large numbers of genetic markers and to evaluate these markers relative to phenotypic observations. In this review, David Severson discusses applications of these techniques for the analysis of mosquito vector competence.
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Affiliation(s)
- D W Severson
- Department of Animal Health and Biomedical Sciences, 1655 Linden Drive, University of Madison, Madison, WI 53706, USA
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Higgs S, Powers AM, Olson KE. Alphavirus expression systems: Applications to mosquito vector studies. ACTA ACUST UNITED AC 1993; 9:444-52. [PMID: 15463689 DOI: 10.1016/0169-4758(93)90098-z] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In this review, Steve Higgs, Ann Powers and Ken Olson describe how alphavirus expression systems, based on infectious cDNA clones of Sindbis virus, constitute a novel RNA virus delivery system suitable for the efficient expression of heterologous gene products or RNA sequences in mosquito cells or adult mosquitoes. The technique permits ready assessment of molecular genetic-based methods of intracellular interference to infection and provides a powerful new tool for molecular biological studies in arthropods.
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Affiliation(s)
- S Higgs
- Department of Microbiology, Colorado State University, Fort Collins, CO 80523, USA
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Abstract
A basic fact in malariology is that human malaria infections result from the bite of an infective anopheline mosquito. Without sporozoite transmission there is no malaria. Here, John Beier highlights our understanding of sporozoite biology from the perspective of how sporozoites develop and survive in mosquitoes, how they are transmitted during bloodfeeding, and how key elements in sporozoite-vector relationships present new opportunities for tackling critical questions relevant for disease control.
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Affiliation(s)
- J C Beier
- Department of Immunology and Infectious Diseases, School of Hygiene and Public Health, The Johns Hopkins University, 615 North Wolfe Street, Baltimore, MD 21205, USA
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