1
|
Abstract
Releases of sterile males are the gold standard for many insect population control programs, and precise sex sorting to remove females prior to male releases is essential to the success of these operations. To advance traditional methods for scaling the generation of sterile males, we previously described a CRISPR-mediated precision-guided sterile insect technique (pgSIT), in which Cas9 and gRNA strains are genetically crossed to generate sterile males for mass release. While effective at generating F1 sterile males, pgSIT requires a genetic cross between the two parental strains, which requires maintenance and sexing of two strains in a factory. Therefore, to advance pgSIT further by removing this crossing step, here we describe a next-generation temperature-inducible pgSIT (TI-pgSIT) technology and demonstrate its proof-of-concept in Drosophila melanogaster. Importantly, we were able to develop a true breeding strain for TI-pgSIT that eliminates the requirement for sex sorting-a feature that may help further automate production at scale.
Collapse
Affiliation(s)
- Nikolay P. Kandul
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, California, USA
| | - Junru Liu
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, California, USA
| | - Omar S. Akbari
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, California, USA
| |
Collapse
|
2
|
Kolliopoulou A, Taning CNT, Smagghe G, Swevers L. Viral Delivery of dsRNA for Control of Insect Agricultural Pests and Vectors of Human Disease: Prospects and Challenges. Front Physiol 2017; 8:399. [PMID: 28659820 PMCID: PMC5469917 DOI: 10.3389/fphys.2017.00399] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Accepted: 05/26/2017] [Indexed: 12/12/2022] Open
Abstract
RNAi is applied as a new and safe method for pest control in agriculture but efficiency and specificity of delivery of dsRNA trigger remains a critical issue. Various agents have been proposed to augment dsRNA delivery, such as engineered micro-organisms and synthetic nanoparticles, but the use of viruses has received relatively little attention. Here we present a critical view of the potential of the use of recombinant viruses for efficient and specific delivery of dsRNA. First of all, it requires the availability of plasmid-based reverse genetics systems for virus production, of which an overview is presented. For RNA viruses, their application seems to be straightforward since dsRNA is produced as an intermediate molecule during viral replication, but DNA viruses also have potential through the production of RNA hairpins after transcription. However, application of recombinant virus for dsRNA delivery may not be straightforward in many cases, since viruses can encode RNAi suppressors, and virus-induced silencing effects can be determined by the properties of the encoded RNAi suppressor. An alternative is virus-like particles that retain the efficiency and specificity determinants of natural virions but have encapsidated non-replicating RNA. Finally, the use of viruses raises important safety issues which need to be addressed before application can proceed.
Collapse
Affiliation(s)
- Anna Kolliopoulou
- Insect Molecular Genetics and Biotechnology Research Group, Institute of Biosciences and Applications, NCSR “Demokritos,”Aghia Paraskevi, Greece
| | - Clauvis N. T. Taning
- Laboratory of Agrozoology, Department of Crop Protection, Faculty of Bioscience Engineering, Ghent UniversityGhent, Belgium
| | - Guy Smagghe
- Laboratory of Agrozoology, Department of Crop Protection, Faculty of Bioscience Engineering, Ghent UniversityGhent, Belgium
| | - Luc Swevers
- Insect Molecular Genetics and Biotechnology Research Group, Institute of Biosciences and Applications, NCSR “Demokritos,”Aghia Paraskevi, Greece
| |
Collapse
|
3
|
Biological Control Strategies for Mosquito Vectors of Arboviruses. INSECTS 2017; 8:insects8010021. [PMID: 28208639 PMCID: PMC5371949 DOI: 10.3390/insects8010021] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Accepted: 01/21/2017] [Indexed: 12/16/2022]
Abstract
Historically, biological control utilizes predatory species and pathogenic microorganisms to reduce the population of mosquitoes as disease vectors. This is particularly important for the control of mosquito-borne arboviruses, which normally do not have specific antiviral therapies available. Although development of resistance is likely, the advantages of biological control are that the resources used are typically biodegradable and ecologically friendly. Over the past decade, the advancement of molecular biology has enabled optimization by the manipulation of genetic materials associated with biological control agents. Two significant advancements are the discovery of cytoplasmic incompatibility induced by Wolbachia bacteria, which has enhanced replacement programs, and the introduction of dominant lethal genes into local mosquito populations through the release of genetically modified mosquitoes. As various arboviruses continue to be significant public health threats, biological control strategies have evolved to be more diverse and become critical tools to reduce the disease burden of arboviruses.
Collapse
|
4
|
Alrefaei YN, Okatcha TI, Skinner DE, Brindley PJ. Progress with schistosome transgenesis. Mem Inst Oswaldo Cruz 2012; 106:785-93. [PMID: 22124549 DOI: 10.1590/s0074-02762011000700002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2011] [Accepted: 05/20/2011] [Indexed: 11/22/2022] Open
Abstract
Genome sequences for Schistosoma japonicum and Schistosoma mansoni are now available. The schistosome genome encodes ~13,000 protein encoding genes for which the function of only a minority is understood. There is a valuable role for transgenesis in functional genomic investigations of these new schistosome gene sequences. In gain-of-function approaches, transgenesis can lead to integration of transgenes into the schistosome genome which can facilitate insertional mutagenesis screens. By contrast, transgene driven, vector-based RNA interference (RNAi) offers powerful loss-of-function manipulations. Our laboratory has focused on development of tools to facilitate schistosome transgenesis. We have investigated the utility of retroviruses and transposons to transduce schistosomes. Vesicular stomatitis virus glycoprotein (VSVG) pseudotyped murine leukemia virus (MLV) can transduce developmental stages of S. mansoni including eggs. We have also observed that the piggyBac transposon is transpositionally active in schistosomes. Approaches with both VSVG-MLV and piggyBac have resulted in somatic transgenesis and have lead to integration of active reporter transgenes into schistosome chromosomes. These findings provided the first reports of integration of reporter transgenes into schistosome chromosomes. Experience with these systems is reviewed herewith, along with findings with transgene mediated RNAi and germ line transgenesis, in addition to pioneering and earlier reports of gene manipulation for schistosomes.
Collapse
Affiliation(s)
- Yousef Noori Alrefaei
- Department of Microbiology, Immunology and Tropical Medicine, George Washington University Medical Center, Washington, DC, USA
| | | | | | | |
Collapse
|
5
|
Pantropic retroviruses as a transduction tool for sea urchin embryos. Proc Natl Acad Sci U S A 2012; 109:5334-9. [PMID: 22431628 DOI: 10.1073/pnas.1117846109] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Sea urchins are an important model for experiments at the intersection of development and systems biology, and technical innovations that enhance the utility of this model are of great value. This study explores pantropic retroviruses as a transduction tool for sea urchin embryos, and demonstrates that pantropic retroviruses infect sea urchin embryos with high efficiency and genomically integrate at a copy number of one per cell. We successfully used a self-inactivation strategy to both insert a sea urchin-specific enhancer and disrupt the endogenous viral enhancer. The resulting self-inactivating viruses drive global and persistent gene expression, consistent with genomic integration during the first cell cycle. Together, these data provide substantial proof of principle for transduction technology in sea urchin embryos.
Collapse
|
6
|
Yang S, Brindley PJ, Zeng Q, Li Y, Zhou J, Liu Y, Liu B, Cai L, Zeng T, Wei Q, Lan L, McManus DP. Transduction of Schistosoma japonicum schistosomules with vesicular stomatitis virus glycoprotein pseudotyped murine leukemia retrovirus and expression of reporter human telomerase reverse transcriptase in the transgenic schistosomes. Mol Biochem Parasitol 2010; 174:109-16. [PMID: 20692298 PMCID: PMC3836731 DOI: 10.1016/j.molbiopara.2010.07.007] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2009] [Revised: 07/25/2010] [Accepted: 07/28/2010] [Indexed: 01/21/2023]
Abstract
Although draft genome sequences of two of the major human schistosomes, Schistosoma japonicum and Schistosoma mansoni are available, the structures and characteristics of most genes and the influence of exogenous genes on the metabolism of schistosomes remain uncharacterized. Furthermore, which functional genomics approaches will be tractable for schistosomes are not yet apparent. Here, the vesicular stomatitis virus glycoprotein (VSVG)-pseudotyped pantropic retroviral vector pBABE-puro was modified to incorporate the human telomerase reverse transcriptase gene (hTERT) as a reporter, under the control of the retroviral long terminal repeat (LTR). Pseudotyped virions were employed to transduce S. japonicum to investigate the utility of retrovirus-mediated transgenesis of S. japonicum and the activity of human telomerase reverse transcriptase as a reporter transgene in schistosomes. Schistosomules perfused from experimentally infected rabbits were cultured for 6 days after exposure to the virions after which genomic DNAs from virus exposed and control worms were extracted. Analysis of RNA from transduced parasites and immunohistochemistry of thin parasite sections revealed expression of hTERT in the transduced worms. Expression of hTERT was also confirmed by immunoblot analysis. These findings indicated that S. japonicum could be effectively transduced by VSVG-pseudotyped retrovirus carrying the hTERT gene. Given the potential of hTERT to aid in derivation of immortalized cells, these findings suggest that this pantropic retroviral approach can be employed to transduce cells from specific tissues and organs of schistosomes to investigate the influence of transgene hTERT on growth and proliferation of schistosome cells.
Collapse
Affiliation(s)
- Shenghui Yang
- Centre of Cell and Molecular Biology Experiment, Xiangya School of Medicine, Central South University, Changsha, Hunan province, China
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
7
|
Tchoubrieva EB, Ong PC, Pike RN, Brindley PJ, Kalinna BH. Vector-based RNA interference of cathepsin B1 in Schistosoma mansoni. Cell Mol Life Sci 2010; 67:3739-48. [PMID: 20339897 PMCID: PMC11115793 DOI: 10.1007/s00018-010-0345-3] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2009] [Revised: 03/05/2010] [Accepted: 03/08/2010] [Indexed: 10/19/2022]
Abstract
In helminth parasites, proteolytic enzymes have been implicated in facilitating host invasion, moulting, feeding, and evasion of the host immune response. These key functions render them potential targets for anti-parasite chemotherapy and immunotherapy. Schistosomes feed on host blood and the digested haemoglobin is their major source of amino acids. Haemoglobin digestion is essential for parasite development, growth, and reproduction. We recently reported the use of pseudotyped Moloney murine leukaemia virus to accomplish transformation of Schistosoma mansoni. Here, we report the design of a viral vector expressing a dsRNA hairpin to silence expression of the schistosome cathepsin B1 (SmCB1) gene. We observed 80% reduction in transcript level 72 h after virus exposure and complete silencing of enzyme activity in transduced worms. This is the first report using this technology in any helminth parasite. It will facilitate the evaluation of potential drug targets and biochemical pathways for novel interventions in schistosomes.
Collapse
Affiliation(s)
- Elissaveta B. Tchoubrieva
- Centre for Animal Biotechnology, Faculty of Veterinary Science, The University of Melbourne, Parkville, VIC 3052 Australia
| | - Poh C. Ong
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800 Australia
| | - Robert N. Pike
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800 Australia
| | - Paul J. Brindley
- Department of Microbiology, Immunology and Tropical Medicine, George Washington University Medical Centre, Washington, DC 20037 USA
| | - Bernd H. Kalinna
- Centre for Animal Biotechnology, Faculty of Veterinary Science, The University of Melbourne, Parkville, VIC 3052 Australia
| |
Collapse
|
8
|
Nawtaisong P, Keith J, Fraser T, Balaraman V, Kolokoltsov A, Davey RA, Higgs S, Mohammed A, Rongsriyam Y, Komalamisra N, Fraser MJ. Effective suppression of Dengue fever virus in mosquito cell cultures using retroviral transduction of hammerhead ribozymes targeting the viral genome. Virol J 2009; 6:73. [PMID: 19497123 PMCID: PMC2704196 DOI: 10.1186/1743-422x-6-73] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2008] [Accepted: 06/04/2009] [Indexed: 11/16/2022] Open
Abstract
Outbreaks of Dengue impose a heavy economic burden on developing countries in terms of vector control and human morbidity. Effective vaccines against all four serotypes of Dengue are in development, but population replacement with transgenic vectors unable to transmit the virus might ultimately prove to be an effective approach to disease suppression, or even eradication. A key element of the refractory transgenic vector approach is the development of transgenes that effectively prohibit viral transmission. In this report we test the effectiveness of several hammerhead ribozymes for suppressing DENV in lentivirus-transduced mosquito cells in an attempt to mimic the transgenic use of these effector molecules in mosquitoes. A lentivirus vector that expresses these ribozymes as a fusion RNA molecule using an Ae. aegypti tRNAval promoter and terminating with a 60A tail insures optimal expression, localization, and activity of the hammerhead ribozyme against the DENV genome. Among the 14 hammerhead ribozymes we designed to attack the DENV-2 NGC genome, several appear to be relatively effective in reducing virus production from transduced cells by as much as 2 logs. Among the sequences targeted are 10 that are conserved among all DENV serotype 2 strains. Our results confirm that hammerhead ribozymes can be effective in suppressing DENV in a transgenic approach, and provide an alternative or supplementary approach to proposed siRNA strategies for DENV suppression in transgenic mosquitoes.
Collapse
Affiliation(s)
- Pruksa Nawtaisong
- Department of Biological Sciences, Eck Institute of Global Health, University of Notre Dame, Notre Dame, Indiana 46556, USA.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
9
|
Lo HL, Yee JK. Production of vesicular stomatitis virus G glycoprotein (VSV-G) pseudotyped retroviral vectors. ACTA ACUST UNITED AC 2008; Chapter 12:Unit 12.7. [PMID: 18428407 DOI: 10.1002/0471142905.hg1207s52] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Retrovirus pseudotype is defined as the genome of one retrovirus encapsidated by the envelope protein of a second virus. The host range of the pseudotype is that of the virus donating the envelope protein. Two procedures that use 293GP cells, which are derived from human kidney 293 cells, are described here. The first is based on the high transient transfection efficiency of 293 cells. The retroviral construct and an expression plasmid for VSV-G are co-transfected into 293GP cells that stably express MLV gag and pol proteins. Transiently generated virus is then harvested during consecutive days following DNA transfection. The second procedure involves stable 293GP cell lines containing the VSV-G gene under the control of a promoter whose activity is regulated by tetracycline. Cell lines containing the retroviral vector of interest are established under noninduced conditions. Infectious virus can be harvested following the induction of VSV-G expression in these cell lines.
Collapse
Affiliation(s)
- Hsin-Lung Lo
- City of Hope National Medical Center, Duarte, California, USA
| | | |
Collapse
|
10
|
Kines KJ, Morales ME, Mann VH, Gobert GN, Brindley PJ. Integration of reporter transgenes into Schistosoma mansoni chromosomes mediated by pseudotyped murine leukemia virus. FASEB J 2008; 22:2936-48. [PMID: 18403630 DOI: 10.1096/fj.08-108308] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The recent release of draft genome sequences of two of the major human schistosomes has underscored the pressing need to develop functional genomics approaches for these significant pathogens. The sequence information also makes feasible genome-scale investigation of transgene integration into schistosome chromosomes. Retrovirus-mediated transduction offers a means to establish transgenic lines of schistosomes, to elucidate schistosome gene function and expression, and to advance functional genomics approaches for these parasites. We investigated the utility of the Moloney murine leukemia retrovirus (MLV) pseudotyped with vesicular stomatitis virus glycoprotein (VSVG) for the transduction of Schistosoma mansoni and delivery of reporter transgenes into schistosome chromosomes. Schistosomula were exposed to virions of VSVG-pseudotyped MLV, after which genomic DNA was extracted from the transduced schistosomes. Southern hybridization analysis indicated the presence of proviral MLV retrovirus in the transduced schistosomes. Fragments of the MLV transgene and flanking schistosome sequences recovered using an anchored PCR-based approach demonstrated definitively that somatic transgenesis of schistosome chromosomes had taken place and, moreover, revealed widespread retrovirus integration into schistosome chromosomes. More specifically, MLV transgenes had inserted in the vicinity of genes encoding immunophilin, zinc finger protein Sma-Zic, and others, as well as near the endogenous schistosome retrotransposons, the fugitive and SR1. Proviral integration of the MLV transgene appeared to exhibit primary sequence site specificity, targeting a gGATcc-like motif. Reporter luciferase transgene activity driven by the schistosome actin gene promoter was expressed in the tissues of transduced schistosomula and adult schistosomes. Luciferase activity appeared to be developmentally expressed in schistosomula with increased activity observed after 1 to 2 wk in culture. These findings indicate the utility of VSVG-pseudotyped MLV for transgenesis of S. mansoni, herald a tractable pathway forward toward germline transgenesis and functional genomics of parasitic helminths, and provide the basis for comparative molecular pathogenesis studies of chromosomal lesions arising from retroviral integration into human compared with schistosome chromosomes.
Collapse
Affiliation(s)
- Kristine J Kines
- Department of Tropical Medicine, and Biomedical Sciences Program, Tulane University Health Sciences Center, New Orleans, Louisiana, USA
| | | | | | | | | |
Collapse
|
11
|
Pear W. Transient transfection methods for preparation of high-titer retroviral supernatants. ACTA ACUST UNITED AC 2008; Chapter 9:Unit9.11. [PMID: 18265279 DOI: 10.1002/0471142727.mb0911s36] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Generation of high-titer retrovirus by transient production not only is less laborious than production of stable retroviral producer cell lines, but also has allowed the production of high-titer retroviral supernatants from cDNAs that cannot be achieved by stable producer cell lines. Transient transfection has also increased the versatility of retrovirus-mediated gene transfer to include the rapid testing of different constructs, viral pseudotyping, and construction of retroviral cDNA libraries. Systems based on human 293 cells, an adenovirus-transformed human embryonic kidney cell line have produced the highest retroviral titers and are the most widely used. This unit describes methods for optimizing retroviral production from the 293-based systems and for growing and freezing 293 cells. Methods are included for pseudotyping the virus with VSV G protein by sequential transfection or cotransfection. Virus produced by transiently transfected cells can be used to infect cells. Protocols are provided for infection of adherent cells either directly with retroviral supernatant or by spin infection. In addition, procedures are included for infection of nonadherent cells by addition of retrovirus supernatant, cocultivation with producer cells, or spin infection. These infection methods are also applicable to retrovirus produced by any of the stable producer cell lines.
Collapse
Affiliation(s)
- W Pear
- University of Pennsylvania, Philadelphia, Pennsylvania, USA
| |
Collapse
|
12
|
Abstract
Draft genome sequences for Schistosoma mansoni and Schistosoma japonicum are now available. However, the identity and importance of most schistosome genes have yet to be determined. Recently, progress has been made towards the genetic manipulation and transgenesis of schistosomes. Both loss-of-function and gain-of-function approaches appear to be feasible in schistosomes based on findings described in the past 5 years. This review focuses on reports of schistosome transgenesis, specifically those dealing with the transformation of schistosomes with exogenous mobile genetic elements and/or their endogenous relatives for the genetic manipulation of schistosomes. Transgenesis mediated by mobile genetic elements offers a potentially tractable route to introduce foreign genes to schistosomes, a means to determine the importance of schistosome genes, including those that could be targeted in novel interventions and the potential to undertake large-scale forward genetics by insertional mutagenesis.
Collapse
|
13
|
Bossin H, Furlong RB, Gillett JL, Bergoin M, Shirk PD. Somatic transformation efficiencies and expression patterns using the JcDNV and piggyBac transposon gene vectors in insects. INSECT MOLECULAR BIOLOGY 2007; 16:37-47. [PMID: 17257207 DOI: 10.1111/j.1365-2583.2006.00693.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
A somatic transformation gene vector that exploits the genomic integration properties of Junonia coenia lepidopteran densovirus (JcDNV) sequences in vivo has been developed. JcDNV somatic transformation vectors are derivatives of plasmids containing an interrupted genome of JcDNV that provide efficient, robust vectors that can be used to examine regulation of chromosomally integrated transgenes in insects. Microinjection of JcDNV plasmids into syncytial embryos of Drosophila melanogaster or the lepidopterans Plodia interpunctella, Ephestia kuehniella or Trichoplusia ni resulted in persistent transgene expression throughout development. Inclusion of transgenes with tissue-specific promoters resulted in expression patterns canonical with phenotypes of piggyBac germline transformants. Somatic transformation required the presence of the viral inverted terminal repeat in cis only and did not depend upon non-structural viral proteins.
Collapse
Affiliation(s)
- H Bossin
- Center for Medical, Agricultural and Veterinary Entomology, Agricultural Research Service, US Department of Agriculture, Gainesville, Florida 32608, USA
| | | | | | | | | |
Collapse
|
14
|
Kines KJ, Mann VH, Morales ME, Shelby BD, Kalinna BH, Gobert GN, Chirgwin SR, Brindley PJ. Transduction of Schistosoma mansoni by vesicular stomatitis virus glycoprotein-pseudotyped Moloney murine leukemia retrovirus. Exp Parasitol 2006; 112:209-20. [PMID: 16530185 DOI: 10.1016/j.exppara.2006.02.003] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2006] [Revised: 01/30/2006] [Accepted: 02/01/2006] [Indexed: 11/23/2022]
Abstract
Retroviral transduction of cultured schistosomes offers a potential means to establish transgenic lines of schistosomes and thereby to facilitate the elucidation of schistosome gene function and expression. The Moloney murine leukemia retroviral (MMLV) vector pLNHX was modified to incorporate EGFP or luciferase reporter genes under control of schistosome endogenous gene promoters from the spliced leader RNA and HSP70 genes. These constructs and a plasmid encoding vesicular stomatitis virus glycoprotein (VSVG) were utilized along with GP2-293 cells to produce replication incompetent retrovirus particles pseudotyped with the VSVG envelope. Exposure of several developmental stages, including sporocysts, of Schistosoma mansoni to these virions was facilitated by incubation with polybrene and/or by centrifugation. The early stages of binding and uptake of virus to the parasite tegument were demonstrated by the immunofluorescence colocalization of VSVG envelope and retroviral capsid proteins. Southern hybridization analysis indicated the integration of proviral forms of the MMLV constructs in genomic DNA isolated from the virus exposed schistosomes. Furthermore, analysis of RNA isolated from virus treated parasites demonstrated the presence of transcripts encoding reporter transgenes. Together these results indicated productive transduction by VSVG pseudotyped MMLV of cultured schistosomes, and suggest a tractable route forward towards heritable schistosome transgenesis.
Collapse
Affiliation(s)
- Kristine J Kines
- Department of Tropical Medicine and Center for Infectious Diseases, Tulane University, Health Sciences Center, New Orleans, LA 70112, USA
| | | | | | | | | | | | | | | |
Collapse
|
15
|
Kolokoltsov AA, Weaver SC, Davey RA. Efficient functional pseudotyping of oncoretroviral and lentiviral vectors by Venezuelan equine encephalitis virus envelope proteins. J Virol 2005; 79:756-63. [PMID: 15613303 PMCID: PMC538582 DOI: 10.1128/jvi.79.2.756-763.2005] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Murine oncoretroviruses and lentiviruses pseudotyped with envelope proteins of alphaviruses have shown great potential in providing broad-host-range, stable vectors for gene therapy. Unlike vesicular stomatitis virus G protein-pseudotyped vectors, they are not neutralized by complement and do not appear to cause significant tissue damage. Here we report the production of murine oncoretroviral and lentiviral vectors pseudotyped with the envelope proteins of Venezuelan equine encephalitis virus (VEEV). When optimized, these pseudotypes achieve titers of 10(6) CFU/ml, which is 5- to 10-fold higher than for previous vectors pseudotyped with envelope proteins from other alphaviruses. They can also be concentrated or stored frozen without significant loss of infectivity. Consistent with the tropism of the envelope donor, they transduce a broad array of human cell types, including lung epithelial cells, neuronal cells, lymphocytes, and fibroblasts. Infection is blocked by agents that inhibit endosomal acidification and by neutralizing antibodies against VEEV. These observations indicate that the pseudotypes present native epitopes on their surface and enter through a VEEV envelope-dependent, pH-sensitive mechanism. The fact that the pseudotypes are unaffected by sera reactive to other alphaviruses indicates that they may be useful when successive gene therapies are required in the presence of an active immune response. In this case, having an array of alphavirus-based vectors with similar cell tropisms would be highly advantageous. These vectors may also be useful in diagnostic assays in which infectious VEEV is undesirable but immune reactivity to native epitopes is required.
Collapse
Affiliation(s)
- Andrey A Kolokoltsov
- Department of Microbiology and Immunology, University of Texas Medical Branch, 301 University Blvd., Galveston, TX 77555, USA
| | | | | |
Collapse
|
16
|
Brault AC, Foy BD, Myles KM, Kelly CLH, Higgs S, Weaver SC, Olson KE, Miller BR, Powers AM. Infection patterns of o'nyong nyong virus in the malaria-transmitting mosquito, Anopheles gambiae. INSECT MOLECULAR BIOLOGY 2004; 13:625-635. [PMID: 15606811 DOI: 10.1111/j.0962-1075.2004.00521.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Arthropod-borne alphaviruses transmitted by mosquitoes almost exclusively use culicines; however, the alphavirus o'nyong-nyong (ONNV) has the unusual characteristic of being transmitted primarily by anopheline mosquitoes. This unusual attribute makes ONNV a valuable tool in the characterization of mosquito determinants of infection as well as a useful expression system in Anopheles species. We developed a series of recombinant alphaviruses, based upon the genome of ONNV, designed for the expression of heterologous genes. The backbone genome is a full-length infectious cDNA clone of ONNV from which wild-type virus can be rescued. Additional constructs are variants of the primary clone and contain the complete genome plus a duplicated subgenomic promoter element with a multiple cloning site for insertion of heterologous genes. We inserted a green fluorescent protein (GFP) gene downstream of this promoter and used it to characterize infection and dissemination patterns of ONNV within An. gambiae mosquitoes. These experiments allowed us to identify atypical sites of initial infection and dissemination patterns in this mosquito species not frequently observed in comparable culicine infections. The utility of these ONNVs for studies in anopheline mosquitoes includes the potential for identification of vector infection determinants and to serve as tools for antimalaria studies. Viruses that can express a heterologous gene in a vector and rapidly and efficiently infect numerous tissues in An. gambiae mosquitoes will be a valuable asset in parasite-mosquito interaction and interference research.
Collapse
Affiliation(s)
- A C Brault
- Division of Vector-Borne Infectious Diseases, Centers for Disease Control and Prevention, Fort Collins, CO 80522, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
17
|
Coil DA, Miller AD. Phosphatidylserine is not the cell surface receptor for vesicular stomatitis virus. J Virol 2004; 78:10920-6. [PMID: 15452212 PMCID: PMC521854 DOI: 10.1128/jvi.78.20.10920-10926.2004] [Citation(s) in RCA: 125] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2004] [Accepted: 06/18/2004] [Indexed: 11/20/2022] Open
Abstract
The envelope protein from vesicular stomatitis virus (VSV) has become an important tool for gene transfer and gene therapy. It is widely used mainly because of its ability to mediate virus entry into all cell types tested to date. Consistent with the broad tropism of the virus, the receptor for VSV is thought to be a ubiquitous membrane lipid, phosphatidylserine (PS). However, the evidence for this hypothesis is indirect and incomplete. Here, we have examined the potential interaction of VSV and PS at the plasma membrane in more detail. Measurements of cell surface levels of PS show a wide range across cell types from different organisms. We demonstrate that there is no correlation between the cell surface PS levels and VSV infection or binding. We also demonstrate that an excess of annexin V, which binds specifically and tightly to PS, does not inhibit infection or binding by VSV. While the addition of PS to cells does allow increased virus entry, we show that this effect is not specific to the VSV envelope. We conclude that PS is not the cell surface receptor for VSV, although it may be involved in a postbinding step of virus entry.
Collapse
Affiliation(s)
- David A Coil
- Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue N., Room C2-105, P.O. Box 19024, Seattle, WA 98109-1024, USA
| | | |
Collapse
|
18
|
Abstract
In light of recent growth in available DNA sequence information for a number of parasitic helminths, it is crucial that suitable gene manipulation technologies are developed to facilitate functional genomic studies in these organisms. In this review we discuss recent progress in the development of these technologies in nematode and platyhelminth parasites of medical and veterinary importance. Specifically, the current status of transient transfection, double-stranded RNA interference and antisense RNA as viable techniques for the manipulation of parasitic helminth gene expression is presented. In addition, the potential for the development of stable, or germ-line, transformation methods in these organisms is also discussed.
Collapse
Affiliation(s)
- Jon P Boyle
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin, 2115 Observatory Drive, Madison, WI 53706, USA
| | | |
Collapse
|
19
|
Kudoh A, Fujita M, Kiyono T, Kuzushima K, Sugaya Y, Izuta S, Nishiyama Y, Tsurumi T. Reactivation of lytic replication from B cells latently infected with Epstein-Barr virus occurs with high S-phase cyclin-dependent kinase activity while inhibiting cellular DNA replication. J Virol 2003; 77:851-61. [PMID: 12502801 PMCID: PMC140784 DOI: 10.1128/jvi.77.2.851-861.2003] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Productive infection and replication of herpesviruses usually occurs in growth-arrested cells, but there has been no direct evidence in the case of Epstein-Barr virus (EBV), since an efficient lytic replication system without external stimuli does not exist for the virus. Expression of the EBV lytic-switch transactivator BZLF1 protein in EBV-negative epithelial tumor cell lines, however, is known to arrest the cell cycle in G(0)/G(1) by induction of the tumor suppressor protein p53 and the cyclin-dependent kinase (CDK) inhibitors p21(WAF-1/CIP-1) and p27(KIP-1), followed by the accumulation of a hypophosphorylated form of the Rb protein. In order to determine the effect of the onset of lytic viral replication on cellular events in latently EBV-infected B LCLs, a tightly controlled induction system of the EBV lytic-replication program by inducible BZLF1 protein expression was established in B95-8 cells. The induction of lytic replication completely arrested cell cycle progression and cellular DNA replication. Surprisingly, the levels of p53, p21(WAF-1/CIP-1), and p27(KIP-1) were constant before and after induction of the lytic program, indicating that the cell cycle arrest induced by the lytic program is not mediated through p53 and the CDK inhibitors. Furthermore, although cellular DNA replication was blocked, elevation of cyclin E/A expression and accumulation of hyperphosphorylated forms of Rb protein were observed, a post-G(1)/S phase characteristic of cells. Thus, while the EBV lytic program promoted specific cell cycle-associated activities involved in the progression from G(1) to S phase, it inhibited cellular DNA synthesis. Such cellular conditions appear to especially favor viral lytic replication.
Collapse
Affiliation(s)
- Ayumi Kudoh
- Division of Virology, Aichi Cancer Center Research Institute, Chikusa-ku, Nagoya 464-8681, Japan
| | | | | | | | | | | | | | | |
Collapse
|
20
|
Atkinson PW, James AA. Germline transformants spreading out to many insect species. ADVANCES IN GENETICS 2002; 47:49-86. [PMID: 12000097 DOI: 10.1016/s0065-2660(02)47002-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The past 5 years have witnessed significant advances in our ability to introduce genes into the genomes of insects of medical and agricultural importance. A number of transposable elements now exist that are proving to be sufficiently robust to allow genetic transformation of species within three orders of insects. In particular all of these transposable elements can be used genetically to transform mosquitoes. These developments, together with the use of suitable genes as genetic markers, have enabled several genes and promoters to be transferred between insect species and their effects on the phenotype of the transgenic insect determined. Within a very short period of time, insights into the function of insect promoters in homologous and heterologous insect species are being gained. Furthermore, strategies aimed at ameliorating the harmful effects of pest insects, such as their ability to vector human pathogens, are now being tested in the pest insects themselves. We review the progress that has been made in the development of transgenic technology in pest insect species and conclude that the repertoire of transposable element-based genetic tools, long available to Drosophila geneticists, can now be applied to other insect species. In addition, it is likely that these developments will lead to the generation of pest insects that display a significantly reduced ability to transmit pathogens in the near future.
Collapse
Affiliation(s)
- Peter W Atkinson
- Department of Entomology, University of California, Riverside 92521, USA
| | | |
Collapse
|
21
|
Eggleston P, Zhao Y. Gene targeting in mosquito cells: a demonstration of 'knockout' technology in extrachromosomal gene arrays. BMC Genet 2001; 2:11. [PMID: 11513755 PMCID: PMC37536 DOI: 10.1186/1471-2156-2-11] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2001] [Accepted: 07/31/2001] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Gene targeting would offer a number of advantages over current transposon-based strategies for insect transformation. These include freedom from both position effects associated with quasi-random integration and concerns over transgene instability mediated by endogenous transposases, independence from phylogenetic restrictions on transposon mobility and the ability to generate gene knockouts. RESULTS We describe here our initial investigations of gene targeting in the mosquito. The target site was a hygromycin resistance gene, stably maintained as part of an extrachromosomal array. Using a promoter-trap strategy to enrich for targeted events, a neomycin resistance gene was integrated into the target site. This resulted in knockout of hygromycin resistance concurrent with the expression of high levels of neomycin resistance from the resident promoter. PCR amplification of the targeted site generated a product that was specific to the targeted cell line and consistent with precise integration of the neomycin resistance gene into the 5' end of the hygromycin resistance gene. Sequencing of the PCR product and Southern analysis of cellular DNA subsequently confirmed this molecular structure. CONCLUSIONS These experiments provide the first demonstration of gene targeting in mosquito tissue and show that mosquito cells possess the necessary machinery to bring about precise integration of exogenous sequences through homologous recombination. Further development of these procedures and their extension to chromosomally located targets hold much promise for the exploitation of gene targeting in a wide range of medically and economically important insect species.
Collapse
Affiliation(s)
- Paul Eggleston
- School of Life Sciences, Keele University, Huxley Building, Keele, Staffordshire, ST5 5BG, UK
| | - Yuguang Zhao
- Current address: Institute of Molecular Medicine, John Radcliffe Hospital, Oxford, OX3 9DS, UK
| |
Collapse
|
22
|
Dirks C, Miller AD. Many nonmammalian cells exhibit postentry blocks to transduction by gammaretroviruses pseudotyped with various viral envelopes, including vesicular stomatitis virus G glycoprotein. J Virol 2001; 75:6375-83. [PMID: 11413304 PMCID: PMC114360 DOI: 10.1128/jvi.75.14.6375-6383.2001] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Previous studies have suggested that Moloney murine leukemia virus (MoMLV)-based vectors pseudotyped with the vesicular stomatitis virus G glycoprotein (VSV-G) have extensive ability to transduce nonmammalian cells. However, we have identified multiple cell lines from fish (FHM), mosquitoes (Mos-55), moths (Sf9 and High-5), flies (S2), and frogs (XPK2) that are not efficiently transduced by MoMLV-based vectors pseudotyped with many different viral envelope proteins, including VSV-G, while the same vectors are functional in these cells following transfection. A comparison of MoMLV-based vector transduction in mammalian and nonmammalian cells shows that the nonmammalian cells exhibit blocks at either entry, reverse transcription, or integration. Additionally, VSV-G-pseudotyped MoMLV-based vector transduction is attenuated in the zebrafish cell line ZF4 at entry and/or reverse transcription, whereas other transduction processes are unaffected. We show that the variation of transduction by MoMLV-based vectors in mammalian and nonmammalian cells is not due to differences in culture conditions or cell division rate but is likely the result of divergence in cellular factors required for retroviral transduction.
Collapse
Affiliation(s)
- C Dirks
- Molecular and Cellular Biology Program, Fred Hutchinson Cancer Research Center, 1100 Fairview Ave. N, Seattle, WA 98109-1024, USA
| | | |
Collapse
|
23
|
Handler AM. A current perspective on insect gene transformation. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2001; 31:111-128. [PMID: 11164334 DOI: 10.1016/s0965-1748(00)00159-4] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The genetic transformation of non-drosophilid insects is now possible with several systems, with germ-line transformation reported in published and unpublished accounts for about 12 species using four different transposon vectors. For some of these species, transformation can now be considered routine. Other vector systems include viruses and bacterial symbionts that have demonstrated utility in species and applications requiring transient expression, and for some, the potential exists for genomic integration. Many of these findings are quite recent, presenting a dramatic turning point in our ability to study and manipulate agriculturally and medically important insects. This review discusses these findings from the perspective of all the contributions that has made this technology a reality, the research that has yet to be done for its safe and efficient use in a broader range of species, and an overview of the available methodology to effectively utilize these systems.
Collapse
Affiliation(s)
- A M Handler
- Center for Medical, Agricultural, and Veterinary Entomology, Agricultural Research Service, US Department of Agriculture, 1700 S.W. 23rd Drive, Gainesville, FL 32608, USA.
| |
Collapse
|
24
|
Atkinson PW, Pinkerton AC, O'Brochta DA. Genetic transformation systems in insects. ANNUAL REVIEW OF ENTOMOLOGY 2001; 46:317-346. [PMID: 11112172 DOI: 10.1146/annurev.ento.46.1.317] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The past 5 years have witnessed the emergence of techniques that permit the stable genetic transformation of a number of non-drosophilid insect species. These transposable-element-based strategies, together with virus-based techniques that allow the expression of genes to be quickly examined in insects, provide insect scientists with a first generation of genetic tools that can begin to be harnessed to further increase our understanding of gene function and regulation in insects. We review and compare the characteristics of these gene transfer systems and conclude that, although significant progress has been made, these systems still do not meet the requirements of robust genetic tools. We also review risk assessment issues arising from the generation and probable release of genetically engineered insects.
Collapse
Affiliation(s)
- P W Atkinson
- Department of Entomology, University of California, Riverside, California 92521, USA.
| | | | | |
Collapse
|
25
|
Molecular strategies for interrupting arthropod-borne virus transmission by mosquitoes. Clin Microbiol Rev 2000. [PMID: 11023962 DOI: 10.1128/cmr.13.4.651-661.2000] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Arthropod-borne virus (arbovirus) infections cause a number of emerging and resurgent human and veterinary infectious diseases. Traditional means of controlling arbovirus diseases include vaccination of susceptible vertebrates and mosquito control, but in many cases these have been unavailable or ineffective, and so novel strategies for disease control are needed. One possibility is genetic manipulation of mosquito vectors to render them unable to transmit arboviruses. This review describes recent work to test the concept of pathogen-derived resistance in arthropods by expression of viral genes in mosquito cell cultures and mosquitoes. Sense and antisense genome sequences from La Crosse virus (LAC) (a member of the Bunyaviridae) and dengue viruses serotypes 1 to 4 (DEN-1 to DEN-4) (members of the Flaviviridae) were expressed in mosquito cells from double-subgenomic and replicon vectors based on Sindbis virus (a member of the Togaviridae). The cells were then challenged with homologous or related viruses. For LAC, expression of antisense sequences from the small (S) genome segment, particularly full-length antisense S RNA, effectively interfered with replication of challenge virus, whereas expression of either antisense or sense RNA from the medium (M) segment was completely ineffective in LAC inhibition. Expression of sense and antisense RNA derived from certain regions of the DEN genome also blocked homologous virus replication more effectively than did RNA from other regions. Other parameters of RNA-mediated interference have been defined, such as the time when replication is blocked and the minimum size of effector RNA. The mechanism of RNA inhibition has not been determined, although it resembles double-stranded RNA interference in other nonvertebrate systems. Prospects for application of molecular strategies to control arbovirus diseases are briefly reviewed.
Collapse
|
26
|
Saraiva E, Fampa P, Cedeno V, Bergoin M, Mialhe E, Miller LH. Expression of heterologous promoters in Lutzomyia longipalpis and Phlebotomus papatasi (Diptera: Psychodidae) cell lines. JOURNAL OF MEDICAL ENTOMOLOGY 2000; 37:802-806. [PMID: 11126533 DOI: 10.1603/0022-2585-37.6.802] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
To establish a transient expression system for genes introduced into sand fly cell lines, we tested the expression of the luciferase reporter gene under control of different promoters. Towards this end, we lipofected cell lines obtained from New and Old World sand flies, LL-5 from Lutzomyia longipalpis Lutz & Neiva and PP-9 from Phlebotomus papatasi Scopoli, respectively. The relative levels of luciferase expression were studied under control of Drosophila melanogaster Meigen heat shock protein 70 (hsp70), human cytomegalovirus, simian virus 40 or Junonia coenia (Hübner) densovirus (P9) promoters. The Drosophila heat shock protein 70 promoter, originating from insect genes, functioned as a strong promoter in both cell lines. Promoters from the different virus genes also were capable of driving transgene expression in both cell lines.
Collapse
Affiliation(s)
- E Saraiva
- Laboratory of Parasitic Disease, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 9000 Rockville Pike, Building 4, Room 126, Bethesda, MD, USA
| | | | | | | | | | | |
Collapse
|
27
|
Blair CD, Adelman ZN, Olson KE. Molecular strategies for interrupting arthropod-borne virus transmission by mosquitoes. Clin Microbiol Rev 2000; 13:651-61. [PMID: 11023962 PMCID: PMC88954 DOI: 10.1128/cmr.13.4.651] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Arthropod-borne virus (arbovirus) infections cause a number of emerging and resurgent human and veterinary infectious diseases. Traditional means of controlling arbovirus diseases include vaccination of susceptible vertebrates and mosquito control, but in many cases these have been unavailable or ineffective, and so novel strategies for disease control are needed. One possibility is genetic manipulation of mosquito vectors to render them unable to transmit arboviruses. This review describes recent work to test the concept of pathogen-derived resistance in arthropods by expression of viral genes in mosquito cell cultures and mosquitoes. Sense and antisense genome sequences from La Crosse virus (LAC) (a member of the Bunyaviridae) and dengue viruses serotypes 1 to 4 (DEN-1 to DEN-4) (members of the Flaviviridae) were expressed in mosquito cells from double-subgenomic and replicon vectors based on Sindbis virus (a member of the Togaviridae). The cells were then challenged with homologous or related viruses. For LAC, expression of antisense sequences from the small (S) genome segment, particularly full-length antisense S RNA, effectively interfered with replication of challenge virus, whereas expression of either antisense or sense RNA from the medium (M) segment was completely ineffective in LAC inhibition. Expression of sense and antisense RNA derived from certain regions of the DEN genome also blocked homologous virus replication more effectively than did RNA from other regions. Other parameters of RNA-mediated interference have been defined, such as the time when replication is blocked and the minimum size of effector RNA. The mechanism of RNA inhibition has not been determined, although it resembles double-stranded RNA interference in other nonvertebrate systems. Prospects for application of molecular strategies to control arbovirus diseases are briefly reviewed.
Collapse
Affiliation(s)
- C D Blair
- Arthropod-Borne and Infectious Diseases Laboratory, Department of Microbiology, Colorado State University, Fort Collins, Colorado 80523-1677, USA.
| | | | | |
Collapse
|
28
|
Killeen GF, Foy BD, Shahabuddin M, Roake W, Williams A, Vaughan TJ, Beier JC. Tagging bloodmeals with phagemids allows feeding of multiple-sample arrays to single cages of mosquitoes (Diptera: Culicidae) and the recovery of single recombinant antibody fragment genes from individual insects. JOURNAL OF MEDICAL ENTOMOLOGY 2000; 37:528-533. [PMID: 10916292 DOI: 10.1603/0022-2585-37.4.528] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A recombinant single-chain variable-region human antibody fragment (scFv) was expressed in Escherichia coli, extracted in hypertonic sucrose, mixed directly with blood and fed to Anopheles gambiae Giles mosquitoes. When E. coli containing the phagemids that encode these scFv were included in bloodmeals, phagemids could be recovered from the mosquito midgut for up to 3 d after feeding. Furthermore, large arrays of such gene-tagged scFv-containing bloodmeals could be fed to cages of mosquitoes using microtiter plates. Arrays of phagemids with and without an antibody insert were fed to single cages of mosquitoes to test whether individual mosquitoes fed from single wells of such arrays. Phagemids were recovered from 95% of blood-fed females and > 80% of these phagemids were monoclonal. Therefore, it is possible to feed multiple sample arrays of recombinant proteins to single cages of mosquitoes and to recover the genetic material that encodes for only one of the array elements from individual mosquitoes. This demonstration indicates that multiple-sample feeding and recovery strategies are feasible and may represent a viable strategy for future rapid screening of biologically active genes, gene products or microorganisms in live arthropods.
Collapse
Affiliation(s)
- G F Killeen
- Department of Tropical Medicine, School of Public Health and Tropical Medicine, Tulane University Medical Center, New Orleans, LA 70112, USA
| | | | | | | | | | | | | |
Collapse
|
29
|
Boulo V, Cadoret JP, Shike H, Shimizu C, Miyanohara A, Burns JC. Infection of cultured embryo cells of the pacific oyster, Crassostrea gigas, by pantropic retroviral vectors. In Vitro Cell Dev Biol Anim 2000; 36:395-9. [PMID: 10949999 DOI: 10.1290/1071-2690(2000)036<0395:ioceco>2.0.co;2] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The inability to stably introduce and express foreign genes has hampered basic research in molluscan species. We cultured cells from dissociated embryos of the Pacific oyster, Crassostrea gigas, and infected these primary cultures with pantropic retroviral vectors containing the envelope glycoprotein of vesicular stomatitis virus. Luciferase transgene expression mediated by different heterologous promoters was demonstrated for at least 9 d after infection of the cells. Surprisingly, the promoter reproducibly mediating the highest level of luciferase expression was the retroviral promoter (U3 region of long terminal repeat) from the Moloney murine leukemia virus. The infection efficiency using a low multiplicity of infection (0.05) was estimated by quantitative polymerase chain reaction to be between 0.1-0.5%. This system will facilitate studies of gene expression and regulation and should be widely applicable to other molluscan species.
Collapse
Affiliation(s)
- V Boulo
- IFREMER-CNRS, Universite Montpellier II, Defense et Resistance chez les Invertebres Marins, France.
| | | | | | | | | | | |
Collapse
|
30
|
Jasinskiene N, Coates CJ, James AA. Structure of hermes integrations in the germline of the yellow fever mosquito, Aedes aegypti. INSECT MOLECULAR BIOLOGY 2000; 9:11-18. [PMID: 10672066 DOI: 10.1046/j.1365-2583.2000.00153.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The Hermes transposable element is derived from the house fly, Musca domestica, and can incorporate into the germline of the yellow fever mosquito, Aedes aegypti. Preliminary Southern analyses indicated that Hermes integrated along with the marker gene into the mosquito genomic DNA. Here we show that Hermes integrations are accompanied by the integration of the donor plasmid as well. In addition, breaks in the donor plasmid DNAs do not occur precisely, or at the end of the terminal inverted repeats, and are accompanied by small deletions in the plasmids. Furthermore, integrations do not cause the typical 8-bp duplications of the target site DNA. No integrations are observed in the absence of a source of Hermes transposase. The Hermes transposase clearly did not catalyse precise cut-and-paste transposition in these transformed lines. It may have integrated the transposon through general recombination or through a partial replicative transposition mechanism. The imprecision of Hermes integration may result from interactions of the transposase with an endogenous hAT-like element in the mosquito genome.
Collapse
Affiliation(s)
- N Jasinskiene
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA 92697-3900, USA
| | | | | |
Collapse
|
31
|
Ui M, Takada M, Arai T, Matsumoto K, Yamada K, Nakahata T, Nishiwaki T, Furukawa Y, Tokino T, Nakamura Y, Iba H. Retrovirus vectors designed for efficient transduction of cytotoxic or cytostatic genes. Gene Ther 1999; 6:1670-8. [PMID: 10516715 DOI: 10.1038/sj.gt.3301009] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
It is difficult to establish stable packaging cell lines producing retrovirus vectors for the expression of anti-oncogenes with cytotoxic or cytostatic potential, because these genes would also affect the growth of the packaging cell lines. To overcome this problem, we designed a transcriptional unit pBabeLPL for vector RNA production, in which the transcription of the exogenous genes is completely suppressed by the presence of a preceding insertion containing the puromycin resistance gene (puro) and a poly(A) addition signal. This insertion is flanked by a tandem pair of loxP, and is designed to be excised after the introduction of Cre recombinase, when transcription of the exogenous gene will be started from the 5'-LTR. The transcriptional unit car- rying LacZ or p53 as the exogenous gene was introduced into a previously constructed prepackaging cell lines PtG-S2, in which the expression of VSV-G is also designed to be initiated by the introduction of Cre recombinase, while the gag-pol gene is expressed continuously. After the introduction of Cre recombinase by an adenovirus vector, LacZ- or p53-expressing VSV-G-pseudotyped retrovirus vectors with the designed structure were produced at high virus titers. The p53 virus was shown to be able to transduce p53 into the entire population of several human cancer cell lines and to induce their growth arrest at the G1 phase, indicating that this vector-producing system will be advantageous for human gene therapy.
Collapse
Affiliation(s)
- M Ui
- Department of Gene Regulation, Institute of Medical Science, University of Tokyo, Tokyo, Japan
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
32
|
Arai T, Takada M, Ui M, Iba H. Dose-dependent transduction of vesicular stomatitis virus G protein-pseudotyped retrovirus vector into human solid tumor cell lines and murine fibroblasts. Virology 1999; 260:109-15. [PMID: 10405362 DOI: 10.1006/viro.1999.9773] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We examined the transduction efficiency of a VSV-G (vesicular stomatitis virus G protein)-pseudotyped vector encoding beta-galactosidase (lacZ) into human solid tumor cell lines and murine fibroblasts, compared with that of an amphotropic vector carrying the same RNA sequence. The ratio of cells transduced with the VSV-G-pseudotyped vector corresponded closely to 1 - e(-m.o.i.), as predicted from a Poisson distribution of transduction to the entire cellular population, while this was not the case for the amphotropic vector. Here m.o.i. (multiplicity of infection) is defined as the ratio of input infectious units (titrated on the corresponding cell line) to the number of cells used for the transduction. At high m.o.i.s (values greater than 3), the VSV-G-pseudotyped vector transduced approximately 95% of the culture population of all cell lines examined. The transduction efficiency of the amphotropic vector, however, was not dose-dependent and reached a plateau or even decreased, especially at high m.o.i.; this may be attributable at least in part to the presence of envelope protein and noninfectious particles that compete for the receptor of infectious amphotropic virus. The copy number of integrated vector proviral DNA and the expression level of lacZ increased almost linearly with the dose of the VSV-G-pseudotyed vector, which could readily achieve multiple transduction of more than 10 copies per cell and afforded about 100-fold more transgene product than could be achieved with the amphotropic vector. These features of both the VSV-G-pseudotyped vector and the amphotropic vector were essentially unaffected by purification using centrifugation. These properties of the vector should be highly advantageous for gene transfer into entire populations of human tumor cell lines at a designed dosage.
Collapse
Affiliation(s)
- T Arai
- Institute of Medical Science, University of Tokyo, Tokyo, 108-8639, Japan
| | | | | | | |
Collapse
|
33
|
Que X, Kim D, Alagon A, Hirata K, Shike H, Shimizu C, Gonzalez A, Burns JC, Reed SL. Pantropic retroviral vectors mediate gene transfer and expression in Entamoeba histolytica. Mol Biochem Parasitol 1999; 99:237-45. [PMID: 10340487 DOI: 10.1016/s0166-6851(99)00021-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Transformation of Entamoeba histolytica has been previously reported, but the foreign genes have all been replicated episomally. Pantropic retroviral vectors based on the Moloney murine leukemia virus with the envelope glycoprotein of vesicular stomatitis virus (VSV-G) have an extremely broad host range and can be concentrated to high titer. To investigate whether these pseudotyped, pantropic vectors can mediate gene transfer and expression in E. histolytica, we constructed a retroviral vector, in which a hygromycin phosphotransferase is expressed from the E. histolytica actin promoter. Data confirm the infection, integration, and expression of a foreign gene mediated by the provirus. To our knowledge, this is the most evolutionarily distant example of successful integration and expression of a mammalian retrovirus. Pantropic retroviral vectors may thus facilitate genetic analysis in species lacking transformation systems.
Collapse
Affiliation(s)
- X Que
- Department of Pathology, University of California, San Diego Medical Center, 92103, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
34
|
Zhao YG, Eggleston P. Comparative analysis of promoters for transient gene expression in cultured mosquito cells. INSECT MOLECULAR BIOLOGY 1999; 8:31-38. [PMID: 9927172 DOI: 10.1046/j.1365-2583.1999.810031.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Three heterologous promoters (hsp70 and actin 5C from Drosophila melanogaster and IE1 from the immediate early gene of the Bombyx mori baculovirus) were assessed for their ability to drive transient luciferase expression in mosquito cells. Overall, the actin 5C promoter was considerably more effective at driving luciferase expression than either hsp70 or IE1 in cell lines derived from Anopheles, Aedes and Culex species. hsp70 functioned well when induced by heat shock and was also induced to a lesser extent by chemicals such as sodium arsenite. IE1 was also an effective initiator of transcription, particularly in two Anopheles cell lines, but generally it performed less well than the actin 5C promoter and was also outperformed by hsp70 in Anopheles gambiae cells.
Collapse
Affiliation(s)
- Y G Zhao
- School of Biological Sciences, University of Liverpool, Donnan Laboratories
| | | |
Collapse
|
35
|
Franco M, Rogers ME, Shimizu C, Shike H, Vogt RG, Burns JC. Infection of lepidoptera with a pseudotyped retroviral vector. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 1998; 28:819-825. [PMID: 9818383 DOI: 10.1016/s0965-1748(98)00056-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Studies requiring the introduction and expression of manipulated gene constructs have been technically difficult in non-drosophilid insects. Retroviruses can be engineered to be replication defective and to serve as vectors for gene constructs of interest. In this study, pseudotyped MoMLV(VSV-G) retroviral vectors are shown to successfully infect lepidopteran cells in vitro and in vivo. In Spodoptera frugiperda cells in vitro and in Manduca sexta in vivo, infection and conversion to proviral DNA were confirmed by PCR amplification and Southern blot hybridization of vector-specific sequences. Gene expression and integration of proviral DNA were also documented in vitro. This is the first report of retroviral infection in lepidoptera and suggests that pseudotyped retroviral vectors could be powerful tools in gene manipulation studies of non-drosophilid insects.
Collapse
Affiliation(s)
- M Franco
- Department of Biological Sciences, University of South Carolina, Columbia 29208, USA
| | | | | | | | | | | |
Collapse
|
36
|
Lardans V, Dissous C. Snail Control Strategies for Reduction of Schistosomiasis Transmission. ACTA ACUST UNITED AC 1998; 14:413-7. [PMID: 17040832 DOI: 10.1016/s0169-4758(98)01320-9] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
As intermediate hosts, molluscs play a major role in the transmission of schistosomes; they are the sites of an intense multiplication of parasites. Thus, snail control strategies are considered a priority for the reduction of schistosomiasis transmission. Here, Vinca Lardans and Colette Dissous review the efficacy of environmental management and the use of molluscicides and biological agents to control snail populations. They then describe the development of diagnostic tests, based on the detection of parasite antigens or specific parasite DNA sequences in snail tissues, to detect the early infection of snails. Finally, they discuss progress in studying the molecular basis of susceptibility and resistance phenotypes, and the possible application of the genetic manipulation of molluscs.
Collapse
Affiliation(s)
- V Lardans
- INSERM U167, Institut Pasteur, 1 rue du Prof. A. Calmette, 59019 Lille Cedex, France
| | | |
Collapse
|
37
|
Abstract
Stable transformed insect cell lines have been used for producing many highly processed heterologous proteins. Current research has focused on development of new expression and selection systems, and enhancement of vector stability. Defining the variation of modification and processing capabilities between cell lines will further enhance complex protein production from insect cells.
Collapse
Affiliation(s)
- T A Pfeifer
- Department of Zoology, University of British Columbia, Vancouver, Canada.
| |
Collapse
|
38
|
Teysset L, Burns JC, Shike H, Sullivan BL, Bucheton A, Terzian C. A Moloney murine leukemia virus-based retroviral vector pseudotyped by the insect retroviral gypsy envelope can infect Drosophila cells. J Virol 1998; 72:853-6. [PMID: 9420299 PMCID: PMC109448 DOI: 10.1128/jvi.72.1.853-856.1998] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The gypsy element of Drosophila melanogaster is the first retrovirus identified so far in invertebrates. Previous data suggest that gypsy ENV-like ORF3 mediates viral infectivity. We have produced in the 293GP/LNhsp701ucL.3 human cell line a Moloney murine leukemia virus-based retroviral vector pseudotyped by the gypsy ENV-like protein. We have shown by immunostaining that the gypsy envelope protein is produced in 293GP/LNhsp701ucL.3 cells and that vector particles collected from these cells can infect Drosophila cells. Our results provide direct evidence that the infectious property of gypsy is due to its ORF3 gene product.
Collapse
Affiliation(s)
- L Teysset
- Centre de Génétique Moléculaire, CNRS, Gif-sur-Yvette, France
| | | | | | | | | | | |
Collapse
|
39
|
PETTIGREW MM, O'NEILL SL. Control of Vector-Borne Disease by Genetic Manipulation of Insect Populations: Technological Requirements and Research Priorities. ACTA ACUST UNITED AC 1997. [DOI: 10.1111/j.1440-6055.1997.tb01477.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
40
|
Recombinant Retroviruses Pseudotyped With the Vesicular Stomatitis Virus G Glycoprotein Mediate Both Stable Gene Transfer and Pseudotransduction in Human Peripheral Blood Lymphocytes. Blood 1997. [DOI: 10.1182/blood.v90.3.952.952_952_957] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
It is essential for the study of T-cell function and the improvement of adoptive cell therapies to efficiently generate large populations of human primary T cells that reliably express foreign genes. This goal is achieved by using recombinant retroviruses pseudotyped with either the gibbon ape leukemia virus (GaLV) envelope or the vesicular stomatitis virus G (VSV-G) glycoprotein. We show here that both retroviral particles mediate stable gene transfer in CD4+ and in CD8+ peripheral blood lymphocytes cultured under optimized conditions. However, VSV-G–pseudotyped virions may cause transduction artifacts that must be carefully excluded. The VSV-G virions require 10- to 100-fold higher concentrations of infectious particles to achieve levels of gene transfer comparable to GaLV-virions. Nonetheless, the physical stability of VSV-G–coated particles enables the concentration of viral stocks to 109 infectious particles per milliliter or more.
Collapse
|
41
|
Recombinant Retroviruses Pseudotyped With the Vesicular Stomatitis Virus G Glycoprotein Mediate Both Stable Gene Transfer and Pseudotransduction in Human Peripheral Blood Lymphocytes. Blood 1997. [DOI: 10.1182/blood.v90.3.952] [Citation(s) in RCA: 136] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
AbstractIt is essential for the study of T-cell function and the improvement of adoptive cell therapies to efficiently generate large populations of human primary T cells that reliably express foreign genes. This goal is achieved by using recombinant retroviruses pseudotyped with either the gibbon ape leukemia virus (GaLV) envelope or the vesicular stomatitis virus G (VSV-G) glycoprotein. We show here that both retroviral particles mediate stable gene transfer in CD4+ and in CD8+ peripheral blood lymphocytes cultured under optimized conditions. However, VSV-G–pseudotyped virions may cause transduction artifacts that must be carefully excluded. The VSV-G virions require 10- to 100-fold higher concentrations of infectious particles to achieve levels of gene transfer comparable to GaLV-virions. Nonetheless, the physical stability of VSV-G–coated particles enables the concentration of viral stocks to 109 infectious particles per milliliter or more.
Collapse
|
42
|
Abstract
DEET remains one of the most effective repellents against a wide variety of insects. Although adverse reactions have been reported in the medical literature and magnified in the press, the compound is remarkably safe and has been used by hundreds of millions of people over the past 40 years. Permethrin is a better deterrent of ticks and, like DEET, is remarkably safe. Concomitant use of these two agents provides superior protection. Citronella and a bath oil, Avon Skin-So-Soft, also provide limited protection against some types of flying insects. The promise of new agents or protective strategies is on the horizon. Recently it was shown that retroviral vectors could be used to integrate and express foreign genes in the malaria mosquito, Anopheles gambiae. Conceivably, a genetically engineered mosquito that is resistant to malaria and other transmissible diseases may one day be developed, obviating some of the need for repellents. Almost certainly, future research will yield additional agents to further protect against mosquitoes.
Collapse
Affiliation(s)
- E A Mafong
- Department of Internal Medicine, University of California, School of Medicine, San Diego, USA
| | | |
Collapse
|
43
|
Besansky NJ, Mukabayire O, Benedict MQ, Rafferty CS, Hamm DM, Mcnitt L. The Anopheles gambiae tryptophan oxygenase gene expressed from a baculovirus promoter complements Drosophila melanogaster vermilion. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 1997; 27:803-805. [PMID: 9443379 DOI: 10.1016/s0965-1748(97)00040-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
An Anopheles gambiae cDNA encoding tryptophan oxygenase was placed under the control of the constitutive baculovirus promoter, ie-1. The chimeric construct, expressed transiently in vermilion (tryptophan oxygenase) mutants of Drosophila melanogaster, partially rescued adult eye color. The successful genetic complementation by this construct demonstrated both the proper function of the tryptophan oxygenase product and the effectiveness of the ie-1 promoter in directing expression of foreign genes in live insects. The functionality of An. gambiae tryptophan oxygenase in a higher fly fulfils predictions based on its structural conservation throughout millions of years of independent evolution.
Collapse
Affiliation(s)
- N J Besansky
- Department of Biological Sciences, University of Notre Dame, IN 46556, USA.
| | | | | | | | | | | |
Collapse
|