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Ittiprasert W, Moescheid MF, Chaparro C, Mann VH, Quack T, Rodpai R, Miller A, Wisitpongpun P, Buakaew W, Mentink-Kane M, Schmid S, Popratiloff A, Grevelding CG, Grunau C, Brindley PJ. Targeted insertion and reporter transgene activity at a gene safe harbor of the human blood fluke, Schistosoma mansoni. CELL REPORTS METHODS 2023; 3:100535. [PMID: 37533651 PMCID: PMC10391569 DOI: 10.1016/j.crmeth.2023.100535] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 05/22/2023] [Accepted: 06/25/2023] [Indexed: 08/04/2023]
Abstract
The identification and characterization of genomic safe harbor sites (GSHs) can facilitate consistent transgene activity with minimal disruption to the host cell genome. We combined computational genome annotation and chromatin structure analysis to predict the location of four GSHs in the human blood fluke, Schistosoma mansoni, a major infectious pathogen of the tropics. A transgene was introduced via CRISPR-Cas-assisted homology-directed repair into one of the GSHs in the egg of the parasite. Gene editing efficiencies of 24% and transgene-encoded fluorescence of 75% of gene-edited schistosome eggs were observed. The approach advances functional genomics for schistosomes by providing a tractable path for generating transgenics using homology-directed, repair-catalyzed transgene insertion. We also suggest that this work will serve as a roadmap for the development of similar approaches in helminths more broadly.
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Affiliation(s)
- Wannaporn Ittiprasert
- Department of Microbiology, Immunology & Tropical Medicine, School of Medicine & Health Sciences, George Washington University, Washington, DC 20037, USA
| | - Max F. Moescheid
- Department of Microbiology, Immunology & Tropical Medicine, School of Medicine & Health Sciences, George Washington University, Washington, DC 20037, USA
- Institute of Parasitology, Biomedical Research Center Seltersberg, Justus Liebig University Giessen, Giessen, Germany
| | - Cristian Chaparro
- IHPE, University of Perpignan Via Domitia, CNRS, IFREMER, University Montpellier, Perpignan, France
| | - Victoria H. Mann
- Department of Microbiology, Immunology & Tropical Medicine, School of Medicine & Health Sciences, George Washington University, Washington, DC 20037, USA
| | - Thomas Quack
- Institute of Parasitology, Biomedical Research Center Seltersberg, Justus Liebig University Giessen, Giessen, Germany
| | - Rutchanee Rodpai
- Department of Microbiology, Immunology & Tropical Medicine, School of Medicine & Health Sciences, George Washington University, Washington, DC 20037, USA
- Department of Parasitology and Excellence in Medical Innovation, and Technology Research Group, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand
| | - André Miller
- Schistosomiasis Resource Center, Biomedical Research Institute, Rockville, MD 20850, USA
| | - Prapakorn Wisitpongpun
- Department of Microbiology, Immunology & Tropical Medicine, School of Medicine & Health Sciences, George Washington University, Washington, DC 20037, USA
- Faculty of Medical Technology, Rangsit University, Pathum Thani 12000, Thailand
| | - Watunyoo Buakaew
- Department of Microbiology, Immunology & Tropical Medicine, School of Medicine & Health Sciences, George Washington University, Washington, DC 20037, USA
- Department of Microbiology, Faculty of Medicine, Srinakharinwirot University, Bangkok 10110, Thailand
| | - Margaret Mentink-Kane
- Schistosomiasis Resource Center, Biomedical Research Institute, Rockville, MD 20850, USA
| | - Sarah Schmid
- Schistosomiasis Resource Center, Biomedical Research Institute, Rockville, MD 20850, USA
| | - Anastas Popratiloff
- Nanofabrication and Imaging Center, Science & Engineering Hall, George Washington University, Washington, DC 20052, USA
| | - Christoph G. Grevelding
- Institute of Parasitology, Biomedical Research Center Seltersberg, Justus Liebig University Giessen, Giessen, Germany
| | - Christoph Grunau
- IHPE, University of Perpignan Via Domitia, CNRS, IFREMER, University Montpellier, Perpignan, France
| | - Paul J. Brindley
- Department of Microbiology, Immunology & Tropical Medicine, School of Medicine & Health Sciences, George Washington University, Washington, DC 20037, USA
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Moescheid MF, Puckelwaldt O, Beutler M, Haeberlein S, Grevelding CG. Defining an optimal control for RNAi experiments with adult Schistosoma mansoni. Sci Rep 2023; 13:9766. [PMID: 37328492 PMCID: PMC10276032 DOI: 10.1038/s41598-023-36826-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 06/10/2023] [Indexed: 06/18/2023] Open
Abstract
In parasites such as Schistosoma mansoni, gene knockdown by RNA interference (RNAi) has become an indispensable tool for functional gene characterization. To distinguish target-specific RNAi effects versus off-target effects, controls are essential. To date, however, there is still no general agreement about suitable RNAi controls, which limits the comparability between studies. To address this point, we investigated three selected dsRNAs for their suitability as RNAi controls in experiments with adult S. mansoni in vitro. Two dsRNAs were of bacterial origin, the neomycin resistance gene (neoR) and the ampicillin resistance gene (ampR). The third one, the green fluorescent protein gene (gfp), originated from jellyfish. Following dsRNA application, we analyzed physiological parameters like pairing stability, motility, and egg production as well as morphological integrity. Furthermore, using RT-qPCR we evaluated the potential of the used dsRNAs to influence transcript patterns of off-target genes, which had been predicted by si-Fi (siRNA-Finder). At the physiological and morphological levels, we observed no obvious changes in the dsRNA treatment groups compared to an untreated control. However, we detected remarkable differences at the transcript level of gene expression. Amongst the three tested candidates, we suggest dsRNA of the E. coli ampR gene as the most suitable RNAi control.
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Affiliation(s)
- Max F Moescheid
- Institute of Parasitology, Biomedical Research Center Seltersberg (BFS), Justus Liebig University Giessen, Giessen, Germany
| | - Oliver Puckelwaldt
- Institute of Parasitology, Biomedical Research Center Seltersberg (BFS), Justus Liebig University Giessen, Giessen, Germany
| | - Mandy Beutler
- Institute of Parasitology, Biomedical Research Center Seltersberg (BFS), Justus Liebig University Giessen, Giessen, Germany
| | - Simone Haeberlein
- Institute of Parasitology, Biomedical Research Center Seltersberg (BFS), Justus Liebig University Giessen, Giessen, Germany
| | - Christoph G Grevelding
- Institute of Parasitology, Biomedical Research Center Seltersberg (BFS), Justus Liebig University Giessen, Giessen, Germany.
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3
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Genetic manipulations in helminth parasites. J Parasit Dis 2023; 47:203-214. [PMID: 36712591 PMCID: PMC9869838 DOI: 10.1007/s12639-023-01567-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Accepted: 01/12/2023] [Indexed: 01/24/2023] Open
Abstract
Screening of vaccine or drug target in parasitic helminth is hindered by lack of robust tool for functional studies of parasite protein which account for the availability of only a few anti-helminthic vaccines, diagnostic assay and slower pace of development of an anthelmintic drug. With the piling up of parasite transcriptomic and genomic data, in silico screening for possible vaccine/drug target could be validated by functional characterization of proteins by RNA interference or CRISPR/Cas9. These reverse genetic engineering tools have opened up a better avenue and opportunity for screening parasitic proteins in vitro as well as in vivo. RNA interference provides a technique for silencing targeted mRNA transcript for understanding a gene function in helminth as evidence by work in Caenorhabditis elegans. Recent genetic engineering tool, CRISPR/Cas9 allows knock-out/deletion of the desired gene in parasitic helminths and the other provision it provides in terms of gene knock-in/insertion in parasite genome is still to be explored in future. This manuscript discussed the work that has been carried out on RNAi and CRISPR/Cas9 for functional studies of helminth parasitic proteins.
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Ustyantsev KV, Vavilova VY, Blinov AG, Berezikov EV. Macrostomum lignano as a model to study the genetics and genomics of parasitic flatworms. Vavilovskii Zhurnal Genet Selektsii 2021; 25:108-116. [PMID: 34901708 PMCID: PMC8629357 DOI: 10.18699/vj21.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Revised: 12/03/2020] [Accepted: 12/08/2020] [Indexed: 12/02/2022] Open
Abstract
Hundreds of millions of people worldwide are infected by various species of parasitic flatworms. Without
treatment, acute and chronical infections frequently lead to the development of severe pathologies and even death.
Emerging data on a decreasing efficiency of some important anthelmintic compounds and the emergence of resistance to them force the search for alternative drugs. Parasitic flatworms have complex life cycles, are laborious and
expensive in culturing, and have a range of anatomic and physiological adaptations that complicate the application
of standard molecular-biological methods. On the other hand, free-living flatworm species, evolutionarily close to
parasitic flatworms, do not have the abovementioned difficulties, which makes them potential alternative models
to search for and study homologous genes. In this review, we describe the use of the basal free-living flatworm
Macrostomum lignano as such a model. M. lignano has a number of convenient biological and experimental properties, such as fast reproduction, easy and non-expensive laboratory culturing, optical body transparency, obligatory
sexual reproduction, annotated genome and transcriptome assemblies, and the availability of modern molecular
methods, including transgenesis, gene knockdown by RNA interference, and in situ hybridization. All this makes
M. lignano amenable to the most modern approaches of forward and reverse genetics, such as transposon insertional mutagenesis and methods of targeted genome editing by the CRISPR/Cas9 system. Due to the availability of
an increasing number of genome and transcriptome assemblies of different parasitic flatworm species, new knowledge generated by studying M. lignano can be easily translated to parasitic flatworms with the help of modern
bioinformatic methods of comparative genomics and transcriptomics. In support of this, we provide the results of
our bioinformatics search and analysis of genes homologous between M. lignano and parasitic flatworms, which
predicts a list of promising gene targets for subsequent research.
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Affiliation(s)
- K V Ustyantsev
- Institute of Cytology and Genetics of Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - V Yu Vavilova
- Institute of Cytology and Genetics of Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - A G Blinov
- Institute of Cytology and Genetics of Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - E V Berezikov
- Institute of Cytology and Genetics of Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
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CRISPR-Cas Technology: Emerging Applications in Clinical Microbiology and Infectious Diseases. Pharmaceuticals (Basel) 2021; 14:ph14111171. [PMID: 34832953 PMCID: PMC8625472 DOI: 10.3390/ph14111171] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 11/06/2021] [Accepted: 11/09/2021] [Indexed: 12/26/2022] Open
Abstract
Through the years, many promising tools for gene editing have been developed including zinc-finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs), CRISPR-associated protein 9 (Cas9), and homing endonucleases (HEs). These novel technologies are now leading new scientific advancements and practical applications at an inimitable speed. While most work has been performed in eukaryotes, CRISPR systems also enable tools to understand and engineer bacteria. The increase in the number of multi-drug resistant strains highlights a necessity for more innovative approaches to the diagnosis and treatment of infections. CRISPR has given scientists a glimmer of hope in this area that can provide a novel tool to fight against antimicrobial resistance. This system can provide useful information about the functions of genes and aid us to find potential targets for antimicrobials. This paper discusses the emerging use of CRISPR-Cas systems in the fields of clinical microbiology and infectious diseases with a particular emphasis on future prospects.
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6
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Skinner DE, Popratiloff A, Alrefaei YN, Mann VH, Rinaldi G, Brindley PJ. Functional analysis of vasa/PL10-like genes in the ovary of Schistosoma mansoni. Mol Biochem Parasitol 2020; 236:111259. [PMID: 31958469 DOI: 10.1016/j.molbiopara.2020.111259] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 12/23/2019] [Accepted: 01/13/2020] [Indexed: 02/02/2023]
Abstract
The RNA helicase Vasa plays a pivotal role in the development of the germ line. To decipher the functional roles of vasa/PL10-like genes in the human blood fluke Schistosoma mansoni, we performed RNA interference followed by the analysis of the ovary in the adult female. Double-stranded RNA targeting the schistosome vasa-like gene Smvlg1 reduced the volume of the ovary. Changes in morphology of the ovary were analysed using carmine red-staining of the parasites followed by a novel confocal laser scanning microscopy (CLSM)-based approach to control for natural autofluorescence in female schistosome tissues. The reduction in the ovary volume may have been promoted by the loss of germ cells. By contrast, significant differences were not apparent in the number of eggs produced or hatching rate of eggs laid by the female schistosomes transfected with Smvlg1-specific dsRNA. The findings suggested a role for S. mansoni vasa/PL10-like gene -1 in germ cell development within the schistosome ovary that might impact in the pathogenesis and disease transmission by this neglected tropical disease pathogen.
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Affiliation(s)
- Danielle E Skinner
- Department of Microbiology, Immunology & Tropical Medicine, and Research Center for Neglected Diseases of Poverty, School of Medicine & Health Sciences, The George Washington University, Washington, DC 20037 USA; Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego 9500 Gilman Dr, La Jolla, CA, 92093, USA
| | - Anastas Popratiloff
- Nanofabrication and Imaging Center, The George Washington University, Washington, DC 20052, USA
| | - Yousef N Alrefaei
- Department of Microbiology, Immunology & Tropical Medicine, and Research Center for Neglected Diseases of Poverty, School of Medicine & Health Sciences, The George Washington University, Washington, DC 20037 USA; Department of Medical Laboratory Technology, The Public Authority of Applied Education and Training, Shuwaikh, Kuwait
| | - Victoria H Mann
- Department of Microbiology, Immunology & Tropical Medicine, and Research Center for Neglected Diseases of Poverty, School of Medicine & Health Sciences, The George Washington University, Washington, DC 20037 USA
| | - Gabriel Rinaldi
- Department of Microbiology, Immunology & Tropical Medicine, and Research Center for Neglected Diseases of Poverty, School of Medicine & Health Sciences, The George Washington University, Washington, DC 20037 USA; Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridgeshire, UK.
| | - Paul J Brindley
- Department of Microbiology, Immunology & Tropical Medicine, and Research Center for Neglected Diseases of Poverty, School of Medicine & Health Sciences, The George Washington University, Washington, DC 20037 USA.
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Protein extract from head-foot tissue of Oncomelania hupensis promotes the growth and development of mother sporocysts of Schistosoma japonicum via upregulation of parasite aldolase gene. Parasitol Res 2019; 118:1821-1831. [PMID: 31011809 DOI: 10.1007/s00436-019-06308-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Accepted: 03/27/2019] [Indexed: 10/27/2022]
Abstract
Previous studies showed that protein extract from head-foot tissue of Oncomelania hupensis (O. hupensis) (PhfO), when cocultured with mother sporocysts of Schistosoma japonicum (S. japonicum), was beneficial for parasite's growth and development but the underlying mechanisms remain unclear. One possible strategy for PhfO to promote the growth and development of mother sporocysts of S. japonicum is to upregulate parasite's survival genes. Fructose-1,6-bisphosphate aldolase (ALD), an essential enzyme of glycometabolism in the energy metabolism process, plays an important role in the survival and the growth and development of schistosomes. Using an in vitro coculture system, in this study, we analyzed the potential involvement of the ald gene in the growth and development of mother sporocysts of S. japonicum following coculture with PhfO. We found that coculture with PhfO promoted the growth and development and the survival of mother sporocysts, and increased parasites' ATP consumption level. Mother sporocysts cocultured with PhfO showed a significantly increased expression of the ald gene at both RNA and protein levels. The ALD protein mainly expressed in the cytoplasm of mother sporocysts. Knockdown of ald gene in parasites decreased the ALD protein expression and the ATP consumption level, suppressed the growth and development, and attenuated the survival of mother sporocysts. In ald knockdown mother sporocysts, the effects of PhfO on the ALD expression, the ATP consumption level, the growth and development, and the survival of larvae were significantly abolished. Therefore, the data suggest that PhfO could promote the growth and development, and the survival of mother sporocysts of S. japonicum via upregulating the expression of the ald gene.
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8
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McVeigh P, Maule AG. Can CRISPR help in the fight against parasitic worms? eLife 2019; 8:44382. [PMID: 30702425 PMCID: PMC6355191 DOI: 10.7554/elife.44382] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Accepted: 01/25/2019] [Indexed: 12/28/2022] Open
Abstract
The first reports of CRISPR/Cas9 genome editing in flatworms could usher in a new era of research on these dangerous human parasites.
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Affiliation(s)
- Paul McVeigh
- School of Biological Sciences, Queen's University of Belfast, Belfast, United Kingdom
| | - Aaron G Maule
- School of Biological Sciences, Queen's University of Belfast, Belfast, United Kingdom
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9
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Developmental Sensitivity in Schistosoma mansoni to Puromycin To Establish Drug Selection of Transgenic Schistosomes. Antimicrob Agents Chemother 2018; 62:AAC.02568-17. [PMID: 29760143 DOI: 10.1128/aac.02568-17] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Accepted: 04/27/2018] [Indexed: 01/05/2023] Open
Abstract
Schistosomiasis is considered the most important disease caused by helminth parasites, in terms of morbidity and mortality. Tools to facilitate gain- and loss-of-function approaches can be expected to precipitate the discovery of novel interventions, and drug selection of transgenic schistosomes would facilitate the establishment of stable lines of engineered parasites. Sensitivity of developmental stages of schistosomes to the aminonucleoside antibiotic puromycin was investigated. For the schistosomulum and sporocyst stages, viability was quantified by fluorescence microscopy following dual staining with fluorescein diacetate and propidium iodine. By 6 days in culture, the 50% lethal concentration (LC50) for schistosomula was 19 μg/ml whereas the sporocysts were 45-fold more resilient. Puromycin potently inhibited the development of in vitro-laid eggs (LC50, 68 ng/ml) but was less effective against liver eggs (LC50, 387 μg/ml). Toxicity for adult stages was evaluated using the xCELLigence-based, real-time motility assay (xWORM), which revealed LC50s after 48 h of 4.9 and 17.3 μg/ml for male and female schistosomes, respectively. Also, schistosomula transduced with pseudotyped retrovirus encoding the puromycin resistance marker were partially rescued when cultured in the presence of the antibiotic. Together, these findings will facilitate selection on puromycin of transgenic schistosomes and the enrichment of cultures of transgenic eggs and sporocysts to facilitate the establishment of schistosome transgenic lines. Streamlining schistosome transgenesis with drug selection will open new avenues to understand parasite biology and hopefully lead to new interventions for this neglected tropical disease.
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Portet A, Pinaud S, Tetreau G, Galinier R, Cosseau C, Duval D, Grunau C, Mitta G, Gourbal B. Integrated multi-omic analyses in Biomphalaria-Schistosoma dialogue reveal the immunobiological significance of FREP-SmPoMuc interaction. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2017; 75:16-27. [PMID: 28257854 DOI: 10.1016/j.dci.2017.02.025] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Revised: 02/23/2017] [Accepted: 02/26/2017] [Indexed: 05/16/2023]
Abstract
The fresh water snail Biomphalaria glabrata is one of the vectors of the trematode pathogen Schistosoma mansoni, which is one of the agents responsible of human schistosomiasis. In this host-parasite interaction, co-evolutionary dynamic results into an infectivity mosaic known as compatibility polymorphism. Integrative approaches including large scale molecular approaches have been conducted in recent years to improve our understanding of the mechanisms underlying compatibility. This review presents the combination of integrated Multi-Omic approaches leading to the discovery of two repertoires of polymorphic and/or diversified interacting molecules: the parasite antigens S. mansoni polymorphic mucins (SmPoMucs) and the B. glabrata immune receptors fibrinogen-related proteins (FREPs). We argue that their interactions may be major components for defining the compatible/incompatible status of a specific snail/schistosome combination.
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Affiliation(s)
- Anaïs Portet
- Univ. Perpignan Via Domitia, IHPE UMR 5244, IFREMER, Univ. Montpellier, F-66860 Perpignan, France
| | - Silvain Pinaud
- Univ. Perpignan Via Domitia, IHPE UMR 5244, IFREMER, Univ. Montpellier, F-66860 Perpignan, France
| | - Guillaume Tetreau
- Univ. Perpignan Via Domitia, IHPE UMR 5244, IFREMER, Univ. Montpellier, F-66860 Perpignan, France
| | - Richard Galinier
- Univ. Perpignan Via Domitia, IHPE UMR 5244, IFREMER, Univ. Montpellier, F-66860 Perpignan, France
| | - Céline Cosseau
- Univ. Perpignan Via Domitia, IHPE UMR 5244, IFREMER, Univ. Montpellier, F-66860 Perpignan, France
| | - David Duval
- Univ. Perpignan Via Domitia, IHPE UMR 5244, IFREMER, Univ. Montpellier, F-66860 Perpignan, France
| | - Christoph Grunau
- Univ. Perpignan Via Domitia, IHPE UMR 5244, IFREMER, Univ. Montpellier, F-66860 Perpignan, France
| | - Guillaume Mitta
- Univ. Perpignan Via Domitia, IHPE UMR 5244, IFREMER, Univ. Montpellier, F-66860 Perpignan, France
| | - Benjamin Gourbal
- Univ. Perpignan Via Domitia, IHPE UMR 5244, IFREMER, Univ. Montpellier, F-66860 Perpignan, France.
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Lok JB, Shao H, Massey HC, Li X. Transgenesis in Strongyloides and related parasitic nematodes: historical perspectives, current functional genomic applications and progress towards gene disruption and editing. Parasitology 2017; 144:327-342. [PMID: 27000743 PMCID: PMC5364836 DOI: 10.1017/s0031182016000391] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Revised: 02/10/2016] [Accepted: 02/10/2016] [Indexed: 12/20/2022]
Abstract
Transgenesis for Strongyloides and Parastrongyloides was accomplished in 2006 and is based on techniques derived for Caenorhabditis elegans over two decades earlier. Adaptation of these techniques has been possible because Strongyloides and related parasite genera carry out at least one generation of free-living development, with adult males and females residing in soil contaminated by feces from an infected host. Transgenesis in this group of parasites is accomplished by microinjecting DNA constructs into the syncytia of the distal gonads of free-living females. In Strongyloides stercoralis, plasmid-encoded transgenes are expressed in promoter-regulated fashion in the F1 generation following gene transfer but are silenced subsequently. Stable inheritance and expression of transgenes in S. stercoralis requires their integration into the genome, and stable lines have been derived from integrants created using the piggyBac transposon system. More direct investigations of gene function involving expression of mutant transgene constructs designed to alter intracellular trafficking and developmental regulation have shed light on the function of the insulin-regulated transcription factor Ss-DAF-16. Transgenesis in Strongyloides and Parastrongyloides opens the possibility of powerful new methods for genome editing and transcriptional manipulation in this group of parasites. Proof of principle for one of these, CRISPR/Cas9, is presented in this review.
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Affiliation(s)
- J B Lok
- Department of Pathobiology,School of Veterinary Medicine,University of Pennsylvania,3800 Spruce Street,Philadelphia,PA 19104,USA
| | - H Shao
- Department of Pathobiology,School of Veterinary Medicine,University of Pennsylvania,3800 Spruce Street,Philadelphia,PA 19104,USA
| | - H C Massey
- Department of Pathobiology,School of Veterinary Medicine,University of Pennsylvania,3800 Spruce Street,Philadelphia,PA 19104,USA
| | - X Li
- Department of Pathobiology,School of Veterinary Medicine,University of Pennsylvania,3800 Spruce Street,Philadelphia,PA 19104,USA
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12
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Chelomina GN. Genomics and transcriptomics of the Chinese liver fluke Clonorchis sinensis (Opisthorchiidae, Trematoda). Mol Biol 2017. [DOI: 10.1134/s0026893317020078] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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13
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Britton C, Roberts B, Marks ND. Functional Genomics Tools for Haemonchus contortus and Lessons From Other Helminths. ADVANCES IN PARASITOLOGY 2016; 93:599-623. [PMID: 27238014 DOI: 10.1016/bs.apar.2016.02.017] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The availability of genome and transcriptome data for parasitic nematodes, including Haemonchus contortus, has highlighted the need to develop functional genomics tools. Comparative genomic analysis, particularly using data from the free-living nematode Caenorhabditis elegans, can help predict gene function. Reliable approaches to study function directly in parasitic nematodes are currently lacking. However, gene knockdown by RNA interference (RNAi) is being successfully used in schistosome and planarian species to define gene functions. Lessons from these systems may be applied to improve RNAi in H. contortus. Previous studies in H. contortus and related nematodes demonstrated reliable RNAi-mediated silencing of some genes, but not others. Current data suggest that susceptibility to RNAi in these nematodes is limited to genes expressed in sites accessible to the environment, such as the gut, amphids and excretory cell. Therefore, RNAi is functional in H. contortus, but improvements are needed to develop this system as a functional genomics platform. Here, we summarize RNAi studies on H. contortus and discuss the optimization of RNA delivery and improvements to culture methods to enhance larval development, protein turnover and the induction of phenotypic effects in vitro. The transgenic delivery of RNA or dominant-negative gene constructs and the recently developed CRISPR/Cas genome-editing technique are considered as potential alternative approaches for gene knockout. This is a key time to devote greater effort in progressing from genome to function, to improve our understanding of the biology of Haemonchus and identify novel targets for parasite control.
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Affiliation(s)
- C Britton
- University of Glasgow, Glasgow, United Kingdom
| | - B Roberts
- University of Glasgow, Glasgow, United Kingdom
| | - N D Marks
- University of Glasgow, Glasgow, United Kingdom
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14
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Cai P, Gobert GN, You H, McManus DP. The Tao survivorship of schistosomes: implications for schistosomiasis control. Int J Parasitol 2016; 46:453-63. [PMID: 26873753 DOI: 10.1016/j.ijpara.2016.01.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Revised: 01/06/2016] [Accepted: 01/06/2016] [Indexed: 01/06/2023]
Abstract
Schistosomiasis, caused by blood flukes of the genus Schistosoma, is a major public health problem which contributes substantially to the economic and financial burdens of many nations in the developing world. An array of survival strategies, such as the unique structure of the tegument which acts as a major host-parasite interface, immune modulation mechanisms, gene regulation, and apoptosis and self-renewal have been adopted by schistosome parasites over the course of long-term evolution with their mammalian definitive hosts. Recent generation of complete schistosome genomes together with numerous biological, immunological, high-throughput "-omics" and gene function studies have revealed the Tao or strategies that schistosomes employ not only to promote long-term survival, but also to ensure effective life cycle transmission. New scenarios for the future control of this important neglected tropical disease will present themselves as our understanding of these Tao increases.
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Affiliation(s)
- Pengfei Cai
- Molecular Parasitology Laboratory, QIMR Berghofer Medical Research Institute, Queensland, Australia.
| | - Geoffrey N Gobert
- Molecular Parasitology Laboratory, QIMR Berghofer Medical Research Institute, Queensland, Australia
| | - Hong You
- Molecular Parasitology Laboratory, QIMR Berghofer Medical Research Institute, Queensland, Australia
| | - Donald P McManus
- Molecular Parasitology Laboratory, QIMR Berghofer Medical Research Institute, Queensland, Australia.
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Moguel B, Moreno-Mendoza N, Bobes RJ, Carrero JC, Chimal-Monroy J, Díaz-Hernández ME, Herrera-Estrella L, Laclette JP. Transient transgenesis of the tapeworm Taenia crassiceps. SPRINGERPLUS 2015; 4:496. [PMID: 26389021 PMCID: PMC4571025 DOI: 10.1186/s40064-015-1278-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Accepted: 08/26/2015] [Indexed: 11/10/2022]
Abstract
Human and porcine cysticercosis is caused by the larval stage of the flatworm Taenia solium (Cestoda). Infestation of the human brain, also known as neurocysticercosis, is the most common parasite disease of the central nervous system worldwide. Significant advances in the understanding of the disease have been achieved using the Taenia crassiceps murine model. We describe here a successful transfection protocol of T. crassiceps cysticerci as the first step to approach a number of currently inaccessible biological questions on cysticercosis. T. crassiceps cysticerci (ORF strain) were microinjected with the plasmid pcDNA3.1/NT-GFP-TOPO, encoding the green fluorescent protein (GFP) driven by a cytomegalovirus promoter (CMV). Twelve hours after the microinjection, GFP fluorescence gradually developed in patches associated to bud structures in the bladder wall of cysts. Fluorescence reached a peak at 24-48 h and lasted up to 72 h after the microinjection. Immunohistochemical studies on tissue sections of transfected cysts using an anti-GFP antibody, demonstrated co-localization of the antibody and the GFP fluorescence in the tegumentary cytoplasm and subtegumentary cytons. To validate at the mRNA level the expression of GFP, we carried out RT-PCR using two pairs of nested primers. Results showed expression of GFP-mRNA at 24 h post-transfection. Moreover, western blot assays of crude extracts of transfected cysts, carried out using the anti-GFP specific antibody, showed the expected protein band of 27 kDa, demonstrating that the GFP expression started at 24 after plasmid microinjection and was maintained up to 72 h. These findings will facilitate the development of functional genomics approaches applied to this model of cysticercosis.
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Affiliation(s)
- Bárbara Moguel
- Institute for Biomedical Research, Universidad Nacional Autónoma de México, Av. Universidad 3000, Coyoacán, C.P. 04510 México DF, México
| | - Norma Moreno-Mendoza
- Institute for Biomedical Research, Universidad Nacional Autónoma de México, Av. Universidad 3000, Coyoacán, C.P. 04510 México DF, México
| | - Raúl J Bobes
- Institute for Biomedical Research, Universidad Nacional Autónoma de México, Av. Universidad 3000, Coyoacán, C.P. 04510 México DF, México
| | - Julio C Carrero
- Institute for Biomedical Research, Universidad Nacional Autónoma de México, Av. Universidad 3000, Coyoacán, C.P. 04510 México DF, México
| | - Jesús Chimal-Monroy
- Institute for Biomedical Research, Universidad Nacional Autónoma de México, Av. Universidad 3000, Coyoacán, C.P. 04510 México DF, México
| | - Martha E Díaz-Hernández
- Institute for Biomedical Research, Universidad Nacional Autónoma de México, Av. Universidad 3000, Coyoacán, C.P. 04510 México DF, México
| | - Luis Herrera-Estrella
- National Laboratory of Genomics for Biodiversity-cinvestav, Km 9.6 Libramiento Norte Carretera Irapuato-León, C.P. 36821 Irapuato, Gto México
| | - Juan P Laclette
- Institute for Biomedical Research, Universidad Nacional Autónoma de México, Av. Universidad 3000, Coyoacán, C.P. 04510 México DF, México
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16
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Transfection of Platyhelminthes. BIOMED RESEARCH INTERNATIONAL 2015; 2015:206161. [PMID: 26090388 PMCID: PMC4450235 DOI: 10.1155/2015/206161] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 08/09/2014] [Accepted: 09/15/2014] [Indexed: 01/22/2023]
Abstract
Flatworms are one of the most diverse groups within Lophotrochozoa with more than 20,000 known species, distributed worldwide in different ecosystems, from the free-living organisms in the seas and lakes to highly specialized parasites living in a variety of hosts, including humans. Several infections caused by flatworms are considered major neglected diseases affecting countries in the Americas, Asia, and Africa. For several decades, a particular interest on free-living flatworms was due to their ability to regenerate considerable portions of the body, implying the presence of germ cells that could be important for medicine. The relevance of reverse genetics for this group is clear; understanding the phenotypic characteristics of specific genes will shed light on developmental traits of free-living and parasite worms. The genetic manipulation of flatworms will allow learning more about the mechanisms for tissue regeneration, designing new and more effective anthelmintic drugs, and explaining the host-parasite molecular crosstalk so far partially inaccessible for experimentation. In this review, availability of transfection techniques is analyzed across flatworms, from the initial transient achievements to the stable manipulations now developed for free-living and parasite species.
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17
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Rinaldi G, Yan H, Nacif-Pimenta R, Matchimakul P, Bridger J, Mann VH, Smout MJ, Brindley PJ, Knight M. Cytometric analysis, genetic manipulation and antibiotic selection of the snail embryonic cell line Bge from Biomphalaria glabrata, the intermediate host of Schistosoma mansoni. Int J Parasitol 2015; 45:527-35. [PMID: 25907768 DOI: 10.1016/j.ijpara.2015.02.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Revised: 02/25/2015] [Accepted: 02/27/2015] [Indexed: 01/14/2023]
Abstract
The invertebrate cell line, Bge, from embryos of the snail Biomphalaria glabrata, remains to date the only established cell line from any species of the Phylum Mollusca. Since its establishment in 1976 by Eder Hansen, few studies have focused on profiling its cytometrics, growth characteristics or sensitivity to xenobiotics. Bge cells are reputed to be challenging to propagate and maintain. Therefore, even though this cell line is a noteworthy resource, it has not been studied widely. With growing interest in functional genomics, including genetic transformation, to elucidate molecular aspects of the snail intermediate hosts responsible for transmission of schistosomiasis, and aiming to enhance the convenience of maintenance of this molluscan cell line, we deployed the xCELLigene real time approach to study Bge cells. Doubling times for three isolates of Bge, termed CB, SL and UK, were longer than for mammalian cell lines - longer than 40 h in complete Bge medium supplemented with 7% fetal bovine serum at 25°C, ranging from ∼42 h to ∼157 h when 40,000 cells were seeded. To assess the potential of the cells for genetic transformation, antibiotic selection was explored. Bge cells were sensitive to the aminonucleoside antibiotic puromycin (from Streptomyces alboniger) from 5 μg/ml to 200 ng/ml, displaying a half maximal inhibitory concentration (IC50) of ∼1.91 μg/ml. Sensitivity to puromycin, and a relatively quick kill time (<48 h in 5 μg/ml) facilitated use of this antibiotic, together with the cognate resistance gene (puromycin N-acetyl-transferase) for selection of Bge cells transformed with the PAC gene (puroR). Bge cells transfected with a plasmid encoding puroR were partially rescued when cultured in the presence of 5 μg/ml of puromycin. These findings pave the way for the development of functional genomic tools applied to the host-parasite interaction during schistosomiasis and neglected tropical trematodiases at large.
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Affiliation(s)
- Gabriel Rinaldi
- Department of Microbiology, Immunology & Tropical Medicine, Research Center for the Neglected Diseases of Poverty, School of Medicine and Health Sciences, George Washington University, Washington, DC 20037, USA
| | - Hongbin Yan
- Department of Microbiology, Immunology & Tropical Medicine, Research Center for the Neglected Diseases of Poverty, School of Medicine and Health Sciences, George Washington University, Washington, DC 20037, USA; State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, China
| | - Rafael Nacif-Pimenta
- Department of Microbiology, Immunology & Tropical Medicine, Research Center for the Neglected Diseases of Poverty, School of Medicine and Health Sciences, George Washington University, Washington, DC 20037, USA; Laboratorio de Laboratório de Esquistossomose, Centro de Pesquisas René Rachou, Fundação Oswaldo Cruz - FIOCRUZ, Belo Horizonte, Minas Gerais, Brazil
| | - Pitchaya Matchimakul
- Department of Microbiology, Immunology & Tropical Medicine, Research Center for the Neglected Diseases of Poverty, School of Medicine and Health Sciences, George Washington University, Washington, DC 20037, USA; Biomedical Sciences Program, Graduate School, Khon Kaen University, Khon Kaen 40002, Thailand; WHO Collaborating Centre for Research and Control of Opisthorchiasis (Southeast Asian Liver Fluke Disease), Tropical Disease Research Laboratory, Department of Pathology, Khon Kaen University, Khon Kaen 40002, Thailand
| | | | - Victoria H Mann
- Department of Microbiology, Immunology & Tropical Medicine, Research Center for the Neglected Diseases of Poverty, School of Medicine and Health Sciences, George Washington University, Washington, DC 20037, USA
| | - Michael J Smout
- Australian Institute of Tropical Health and Medicine, Queensland Tropical Health Alliance, James Cook University, McGregor Rd, Smithfield, Cairns, Queensland 4878, Australia
| | - Paul J Brindley
- Department of Microbiology, Immunology & Tropical Medicine, Research Center for the Neglected Diseases of Poverty, School of Medicine and Health Sciences, George Washington University, Washington, DC 20037, USA
| | - Matty Knight
- Department of Microbiology, Immunology & Tropical Medicine, Research Center for the Neglected Diseases of Poverty, School of Medicine and Health Sciences, George Washington University, Washington, DC 20037, USA.
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18
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Gobert GN, You H, McManus DP. Gaining biological perspectives from schistosome genomes. Mol Biochem Parasitol 2014; 196:21-8. [PMID: 25076011 DOI: 10.1016/j.molbiopara.2014.07.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2014] [Revised: 07/14/2014] [Accepted: 07/17/2014] [Indexed: 02/06/2023]
Abstract
Characterization of the genomic basis underlying schistosome biology is an important strategy for the development of future treatments and interventions. Genomic sequence is now available for the three major clinically relevant schistosome species, Schistosoma mansoni, S. japonicum and S. haematobium, and this information represents an invaluable resource for the future control of human schistosomiasis. The identification of a biologically important, but distinct from the host, schistosome gene product is the ultimate goal for many research groups. While the initial elucidation of the genome of an organism is critical for most biological research, continued improvement or curation of the genome construction should be an ongoing priority. In this review we will discuss prominent recent findings utilizing a systems approach to schistosome biology, as well as the increased use of interference RNA (RNAi). Both of these research strategies are aiming to place parasite genes into a more meaningful biological perspective.
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Affiliation(s)
- Geoffrey N Gobert
- Molecular Parasitology Laboratory, Infectious Diseases Division, QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia.
| | - Hong You
- Molecular Parasitology Laboratory, Infectious Diseases Division, QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - Donald P McManus
- Molecular Parasitology Laboratory, Infectious Diseases Division, QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
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19
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Gava SG, Scholte LLS, Volpini Â, de Paula Oliveira R, Oliveira G. Heterologous expression in Caenorhabditis elegans as an alternative approach to functional studies in Schistosoma mansoni. Front Genet 2014; 5:120. [PMID: 24904631 PMCID: PMC4034150 DOI: 10.3389/fgene.2014.00120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2014] [Accepted: 04/18/2014] [Indexed: 11/13/2022] Open
Affiliation(s)
- Sandra G. Gava
- Grupo de Genômica e Biologia Computacional, Centro de Pesquisas René Rachou, Instituto Nacional de Ciência e Tecnologia em Doenças Tropicais, Fundação Oswaldo Cruz - FIOCRUZBelo Horizonte, Brazil
- Genetics Department, Instituto de Ciências Biológicas, Universidade Federal de Minas GeraisBelo Horizonte, Brazil
| | - Larissa L. S. Scholte
- Grupo de Genômica e Biologia Computacional, Centro de Pesquisas René Rachou, Instituto Nacional de Ciência e Tecnologia em Doenças Tropicais, Fundação Oswaldo Cruz - FIOCRUZBelo Horizonte, Brazil
| | - Ângela Volpini
- Grupo de Genômica e Biologia Computacional, Centro de Pesquisas René Rachou, Instituto Nacional de Ciência e Tecnologia em Doenças Tropicais, Fundação Oswaldo Cruz - FIOCRUZBelo Horizonte, Brazil
| | - Riva de Paula Oliveira
- Núcleo de Pesquisa em Ciências Biológicas, Universidade Federal de Ouro PretoOuro Preto, Brazil
- Departamento de Biodiversidade, Evolução e Meio Ambiente, ICEB, Universidade Federal de Ouro PretoOuro Preto, Brazil
| | - Guilherme Oliveira
- Grupo de Genômica e Biologia Computacional, Centro de Pesquisas René Rachou, Instituto Nacional de Ciência e Tecnologia em Doenças Tropicais, Fundação Oswaldo Cruz - FIOCRUZBelo Horizonte, Brazil
- *Correspondence:
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20
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Paveley RA, Bickle QD. Automated imaging and other developments in whole-organism anthelmintic screening. Parasite Immunol 2014; 35:302-13. [PMID: 23581722 DOI: 10.1111/pim.12037] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2013] [Accepted: 04/06/2013] [Indexed: 12/13/2022]
Abstract
Helminth infections still represent a huge public health problem throughout the developing world and in the absence of vaccines control is based on periodic mass drug administration. Poor efficacy of some anthelmintics and concerns about emergence of drug resistance has highlighted the need for new drug discovery. Most current anthelmintics were discovered through in vivo screening of selected compounds in animal models but recent approaches have shifted towards screening for activity against adult or larval stages in vitro. Larvae are normally available in greater numbers than adults, can often be produced in vitro and are small enough for microplate assays. However, the manual visualization of drug effects in vitro is subjective, laborious and slow. This can be overcome by application of automated readouts including high-content imaging. Incorporated into robotically controlled HTS platforms such methods allow the very large compound collections being made available by the pharmaceutical industry or academic organizations to be screened against helminths for the first time, invigorating the drug discovery pipeline. Here, we review the status of whole-organism screens based on in vitro activity against living worms and highlight the recent progress towards automated image-based readouts.
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Affiliation(s)
- R A Paveley
- Department of Infection and Immunity, London School of Hygiene and Tropical Medicine, London, UK
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21
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Pseudotyped murine leukemia virus for schistosome transgenesis: approaches, methods and perspectives. Transgenic Res 2014; 23:539-56. [DOI: 10.1007/s11248-013-9779-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2013] [Accepted: 12/19/2013] [Indexed: 10/25/2022]
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How might flukes and tapeworms maintain genome integrity without a canonical piRNA pathway? Trends Parasitol 2014; 30:123-9. [PMID: 24485046 DOI: 10.1016/j.pt.2014.01.001] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2013] [Revised: 12/29/2013] [Accepted: 01/06/2014] [Indexed: 12/31/2022]
Abstract
Surveillance by RNA interference is central to controlling the mobilization of transposable elements (TEs). In stem cells, Piwi argonaute (Ago) proteins and associated proteins repress mobilization of TEs to maintain genome integrity. This defense mechanism targeting TEs is termed the Piwi-interacting RNA (piRNA) pathway. In this opinion article, we draw attention to the situation that the genomes of cestodes and trematodes have lost the piwi and vasa genes that are hallmark characters of the germline multipotency program. This absence of Piwi-like Agos and Vasa helicases prompts the question: how does the germline of these flatworms withstand mobilization of TEs? Here, we present an interpretation of mechanisms likely to defend the germline integrity of parasitic flatworms.
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Abstract
Schistosomes are parasitic flatworms that cause schistosomiasis, a neglected tropical disease that affects hundreds of millions worldwide. Treatment and control of schistosomiasis relies almost entirely on the single drug praziquantel (PZQ), making the prospect of emerging drug resistance particularly worrisome. This review will survey reports of PZQ (and other drug) resistance in schistosomes and other platyhelminths, and explore mechanisms by which drug resistance might develop. Newer genomic and post-genomic strategies that offer the promise of better understanding of how drug resistance might arise in these organisms will be discussed. These approaches could also lead to insights into the mode of action of these drugs and potentially provide markers for monitoring the emergence of resistance.
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New frontiers in schistosoma genomics and transcriptomics. J Parasitol Res 2012; 2012:849132. [PMID: 23227308 PMCID: PMC3512318 DOI: 10.1155/2012/849132] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2012] [Accepted: 10/16/2012] [Indexed: 12/11/2022] Open
Abstract
Schistosomes are digenean blood flukes of aves and mammals comprising 23 species. Some species are causative agents of human schistosomiasis, the second major neglected disease affecting over 230 million people worldwide. Modern technologies including the sequencing and characterization of nucleic acids and proteins have allowed large-scale analyses of parasites and hosts, opening new frontiers in biological research with potential biomedical and biotechnological applications. Nuclear genomes of the three most socioeconomically important species (S. haematobium, S. japonicum, and S. mansoni) have been sequenced and are under intense investigation. Mitochondrial genomes of six Schistosoma species have also been completely sequenced and analysed from an evolutionary perspective. Furthermore, DNA barcoding of mitochondrial sequences is used for biodiversity assessment of schistosomes. Despite the efforts in the characterization of Schistosoma genomes and transcriptomes, many questions regarding the biology and evolution of this important taxon remain unanswered. This paper aims to discuss some advances in the schistosome research with emphasis on genomics and transcriptomics. It also aims to discuss the main challenges of the current research and to point out some future directions in schistosome studies.
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25
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Developments in RNA interference and genetic transformation to define gene function in parasitic helminths. Parasitology 2012; 139:557-9. [PMID: 22459432 DOI: 10.1017/s0031182012000108] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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26
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Rinaldi G, Eckert SE, Tsai IJ, Suttiprapa S, Kines KJ, Tort JF, Mann VH, Turner DJ, Berriman M, Brindley PJ. Germline transgenesis and insertional mutagenesis in Schistosoma mansoni mediated by murine leukemia virus. PLoS Pathog 2012; 8:e1002820. [PMID: 22911241 PMCID: PMC3406096 DOI: 10.1371/journal.ppat.1002820] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2012] [Accepted: 06/11/2012] [Indexed: 12/11/2022] Open
Abstract
Functional studies will facilitate characterization of role and essentiality of newly available genome sequences of the human schistosomes, Schistosoma mansoni, S. japonicum and S. haematobium. To develop transgenesis as a functional approach for these pathogens, we previously demonstrated that pseudotyped murine leukemia virus (MLV) can transduce schistosomes leading to chromosomal integration of reporter transgenes and short hairpin RNA cassettes. Here we investigated vertical transmission of transgenes through the developmental cycle of S. mansoni after introducing transgenes into eggs. Although MLV infection of schistosome eggs from mouse livers was efficient in terms of snail infectivity, >10-fold higher transgene copy numbers were detected in cercariae derived from in vitro laid eggs (IVLE). After infecting snails with miracidia from eggs transduced by MLV, sequencing of genomic DNA from cercariae released from the snails also revealed the presence of transgenes, demonstrating that transgenes had been transmitted through the asexual developmental cycle, and thereby confirming germline transgenesis. High-throughput sequencing of genomic DNA from schistosome populations exposed to MLV mapped widespread and random insertion of transgenes throughout the genome, along each of the autosomes and sex chromosomes, validating the utility of this approach for insertional mutagenesis. In addition, the germline-transmitted transgene encoding neomycin phosphotransferase rescued cultured schistosomules from toxicity of the antibiotic G418, and PCR analysis of eggs resulting from sexual reproduction of the transgenic worms in mice confirmed that retroviral transgenes were transmitted to the next (F1) generation. These findings provide the first description of wide-scale, random insertional mutagenesis of chromosomes and of germline transmission of a transgene in schistosomes. Transgenic lines of schistosomes expressing antibiotic resistance could advance functional genomics for these significant human pathogens. DATABASE ACCESSION: Sequence data from this study have been submitted to the European Nucleotide Archive (http://www.ebi.ac.uk/embl) under accession number ERP000379.
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Affiliation(s)
- Gabriel Rinaldi
- Department of Microbiology, Immunology & Tropical Medicine, School of Medicine & Health Sciences, The George Washington University, Washington, DC, United States of America
- Departamento de Genética, Facultad de Medicina, Universidad de la República, (UDELAR), Montevideo, Uruguay
| | - Sabine E. Eckert
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
- Oxford Nanopore Technologies, Oxford, United Kingdom
| | - Isheng J. Tsai
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
| | - Sutas Suttiprapa
- Department of Microbiology, Immunology & Tropical Medicine, School of Medicine & Health Sciences, The George Washington University, Washington, DC, United States of America
- Department of Pathobiology, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Kristine J. Kines
- Department of Microbiology, Immunology & Tropical Medicine, School of Medicine & Health Sciences, The George Washington University, Washington, DC, United States of America
- Tulane Cancer Center, Tulane University Health Sciences Center, New Orleans, Louisiana, United States of America
| | - José F. Tort
- Departamento de Genética, Facultad de Medicina, Universidad de la República, (UDELAR), Montevideo, Uruguay
| | - Victoria H. Mann
- Department of Microbiology, Immunology & Tropical Medicine, School of Medicine & Health Sciences, The George Washington University, Washington, DC, United States of America
| | - Daniel J. Turner
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
- Oxford Nanopore Technologies, Oxford, United Kingdom
| | - Matthew Berriman
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
| | - Paul J. Brindley
- Department of Microbiology, Immunology & Tropical Medicine, School of Medicine & Health Sciences, The George Washington University, Washington, DC, United States of America
- Research Center for Neglected Diseases of Poverty, The George Washington University, Washington, DC, United States of America
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