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Chawla J, Goldowitz I, Oberstaller J, Zhang M, Pires CV, Navarro F, Sollelis L, Wang CCQ, Seyfang A, Dvorin J, Otto TD, Rayner JC, Marti M, Adams JH. Phenotypic Screens Identify Genetic Factors Associated with Gametocyte Development in the Human Malaria Parasite Plasmodium falciparum. Microbiol Spectr 2023; 11:e0416422. [PMID: 37154686 PMCID: PMC10269797 DOI: 10.1128/spectrum.04164-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Accepted: 03/23/2023] [Indexed: 05/10/2023] Open
Abstract
Transmission of the deadly malaria parasite Plasmodium falciparum from humans to mosquitoes is achieved by specialized intraerythrocytic sexual forms called gametocytes. Though the crucial regulatory mechanisms leading to gametocyte commitment have recently come to light, networks of genes that control sexual development remain to be elucidated. Here, we report a pooled-mutant screen to identify genes associated with gametocyte development in P. falciparum. Our results categorized genes that modulate gametocyte progression as hypoproducers or hyperproducers of gametocytes, and the in-depth analysis of individual clones confirmed phenotypes in sexual commitment rates and putative functions in gametocyte development. We present a new set of genes that have not been implicated in gametocytogenesis before and demonstrate the potential of forward genetic screens in isolating genes impacting parasite sexual biology, an exciting step toward the discovery of new antimalarials for a globally significant pathogen. IMPORTANCE Blocking human-to-vector transmission is an essential step toward malaria elimination. Gametocytes are solely responsible for achieving this transmission and represent an opportunity for therapeutic intervention. While these falciform-shaped parasite stages were first discovered in the 1880s, our understanding of the genetic determinants responsible for their formation and molecular mechanisms that drive their development is limited. In this work, we developed a scalable screening methodology with piggyBac mutants to identify genes that influence the development of gametocytes in the most lethal human malaria parasite, P. falciparum. By doing so, we lay the foundation for large-scale functional genomic studies specifically designed to address remaining questions about sexual commitment, maturation, and mosquito infection in P. falciparum. Such functional genetic screens will serve to expedite the identification of essential pathways and processes for the development of novel transmission-blocking agents.
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Affiliation(s)
- Jyotsna Chawla
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida, USA
- Center for Global Health and Infectious Diseases Research, College of Public Health, University of South Florida, Tampa, Florida, USA
| | - Ilana Goldowitz
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, Massachusetts, USA
| | - Jenna Oberstaller
- Center for Global Health and Infectious Diseases Research, College of Public Health, University of South Florida, Tampa, Florida, USA
| | - Min Zhang
- Center for Global Health and Infectious Diseases Research, College of Public Health, University of South Florida, Tampa, Florida, USA
| | - Camilla Valente Pires
- Center for Global Health and Infectious Diseases Research, College of Public Health, University of South Florida, Tampa, Florida, USA
| | - Francesca Navarro
- Boston Children’s Hospital and Harvard Medical School, Harvard Medical School, Boston, Massachusetts, USA
| | - Lauriane Sollelis
- Institute of Infection, Immunity, and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
- Institute of Parasitology Zurich, VetSuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Chengqi C. Q. Wang
- Center for Global Health and Infectious Diseases Research, College of Public Health, University of South Florida, Tampa, Florida, USA
| | - Andreas Seyfang
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida, USA
- Center for Global Health and Infectious Diseases Research, College of Public Health, University of South Florida, Tampa, Florida, USA
| | - Jeffrey Dvorin
- Boston Children’s Hospital and Harvard Medical School, Harvard Medical School, Boston, Massachusetts, USA
| | - Thomas D. Otto
- Institute of Infection, Immunity, and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Julian C. Rayner
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, United Kingdom
| | - Matthias Marti
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, Massachusetts, USA
- Institute of Infection, Immunity, and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
- Institute of Parasitology Zurich, VetSuisse Faculty, University of Zurich, Zurich, Switzerland
| | - John H. Adams
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida, USA
- Center for Global Health and Infectious Diseases Research, College of Public Health, University of South Florida, Tampa, Florida, USA
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Chawla J, Oberstaller J, Adams JH. Targeting Gametocytes of the Malaria Parasite Plasmodium falciparum in a Functional Genomics Era: Next Steps. Pathogens 2021; 10:346. [PMID: 33809464 PMCID: PMC7999360 DOI: 10.3390/pathogens10030346] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 02/25/2021] [Accepted: 03/03/2021] [Indexed: 02/04/2023] Open
Abstract
Mosquito transmission of the deadly malaria parasite Plasmodium falciparum is mediated by mature sexual forms (gametocytes). Circulating in the vertebrate host, relatively few intraerythrocytic gametocytes are picked up during a bloodmeal to continue sexual development in the mosquito vector. Human-to-vector transmission thus represents an infection bottleneck in the parasite's life cycle for therapeutic interventions to prevent malaria. Even though recent progress has been made in the identification of genetic factors linked to gametocytogenesis, a plethora of genes essential for sexual-stage development are yet to be unraveled. In this review, we revisit P. falciparum transmission biology by discussing targetable features of gametocytes and provide a perspective on a forward-genetic approach for identification of novel transmission-blocking candidates in the future.
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Affiliation(s)
- Jyotsna Chawla
- Molecular Medicine, Morsani College of Medicine, University of South Florida, 12901 Bruce B Downs Blvd, MDC 7, Tampa, FL 33612, USA;
| | - Jenna Oberstaller
- Center for Global Health and Infectious Diseases Research and USF Genomics Program, College of Public Health, University of South Florida, 3720 Spectrum Blvd, Suite 404, Tampa, FL 33612, USA;
| | - John H. Adams
- Center for Global Health and Infectious Diseases Research and USF Genomics Program, College of Public Health, University of South Florida, 3720 Spectrum Blvd, Suite 404, Tampa, FL 33612, USA;
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Feng XB, Zheng ZW, Zhang X, Gu J, Feng QL, Huang LH. Discovering genes responsible for silk synthesis in Bombyx mori by piggyBac-based random insertional mutagenesis. INSECT SCIENCE 2019; 26:821-830. [PMID: 29645353 DOI: 10.1111/1744-7917.12595] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Revised: 03/25/2018] [Accepted: 03/25/2018] [Indexed: 06/08/2023]
Abstract
Silkworm mutants are valuable resources for both transgenic breeding and gene discovery. PiggyBac-based random insertional mutagenesis has been widely used in gene functional studies. In order to discover genes involved in silk synthesis, a piggyBac-based random insertional library was constructed using Bombyx mori, and the mutants with abnormal cocoon were particularly screened. By this means, a "thin cocoon" mutant was identified. This mutant revealed thinner cocoon shell and shorter posterior silk gland (PSG) compared with the wild type. The messenger RNA (mRNA) levels of all the three fibroin genes, including Fib-H, Fib-L and P25, were significantly down-regulated in the PSG of mutants. Four piggyBac insertion sites were identified in Aquaporin (AQP), Longitudinals lacking protein-like (Lola), Glutamyl aminopeptidase-like (GluAP) and Loc101744460. The mRNA levels of all the four genes were significantly altered in the silk gland of mutants. In particular, the mRNA amount of AQP, a gene responsible for the regulation of osmotic pressure, decreased dramatically immediately prior to the spinning stage in the anterior silk gland of mutants. The identification of the genes disrupted in the "thin cocoon" mutant in this study provided useful information for understanding silk production and transgenic breeding of silkworms in the future.
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Affiliation(s)
- Xing-Bao Feng
- Guangzhou Key Laboratory of Insect Development Regulation and Applied Research, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Zi-Wen Zheng
- Guangzhou Key Laboratory of Insect Development Regulation and Applied Research, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Xian Zhang
- Guangzhou Key Laboratory of Insect Development Regulation and Applied Research, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Jun Gu
- Guangzhou Key Laboratory of Insect Development Regulation and Applied Research, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Qi-Li Feng
- Guangzhou Key Laboratory of Insect Development Regulation and Applied Research, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Li-Hua Huang
- Guangzhou Key Laboratory of Insect Development Regulation and Applied Research, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, China
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Potential for Isolation of Immortalized Hepatocyte Cell Lines by Liver-Directed In Vivo Gene Delivery of Transposons in Mice. Stem Cells Int 2019; 2019:5129526. [PMID: 31281376 PMCID: PMC6589260 DOI: 10.1155/2019/5129526] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2019] [Accepted: 05/06/2019] [Indexed: 12/14/2022] Open
Abstract
Isolation of hepatocytes and their culture in vitro represent important avenues to explore the function of such cells. However, these studies are often difficult to perform because of the inability of hepatocytes to proliferate in vitro. Immortalization of isolated hepatocytes is thus an important step toward continuous in vitro culture. For cellular immortalization, integration of relevant genes into the host chromosomes is a prerequisite. Transposons, which are mobile genetic elements, are known to facilitate integration of genes of interest (GOI) into chromosomes in vitro and in vivo. Here, we proposed that a combination of transposon- and liver-directed introduction of nucleic acids may confer acquisition of unlimited cellular proliferative potential on hepatocytes, enabling the possible isolation of immortalized hepatocyte cell lines, which has often failed using more traditional immortalization methods.
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Sidik SM, Huet D, Ganesan SM, Huynh MH, Wang T, Nasamu AS, Thiru P, Saeij JPJ, Carruthers VB, Niles JC, Lourido S. A Genome-wide CRISPR Screen in Toxoplasma Identifies Essential Apicomplexan Genes. Cell 2016; 166:1423-1435.e12. [PMID: 27594426 PMCID: PMC5017925 DOI: 10.1016/j.cell.2016.08.019] [Citation(s) in RCA: 485] [Impact Index Per Article: 60.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Revised: 07/25/2016] [Accepted: 08/05/2016] [Indexed: 12/11/2022]
Abstract
Apicomplexan parasites are leading causes of human and livestock diseases such as malaria and toxoplasmosis, yet most of their genes remain uncharacterized. Here, we present the first genome-wide genetic screen of an apicomplexan. We adapted CRISPR/Cas9 to assess the contribution of each gene from the parasite Toxoplasma gondii during infection of human fibroblasts. Our analysis defines ∼200 previously uncharacterized, fitness-conferring genes unique to the phylum, from which 16 were investigated, revealing essential functions during infection of human cells. Secondary screens identify as an invasion factor the claudin-like apicomplexan microneme protein (CLAMP), which resembles mammalian tight-junction proteins and localizes to secretory organelles, making it critical to the initiation of infection. CLAMP is present throughout sequenced apicomplexan genomes and is essential during the asexual stages of the malaria parasite Plasmodium falciparum. These results provide broad-based functional information on T. gondii genes and will facilitate future approaches to expand the horizon of antiparasitic interventions.
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Affiliation(s)
- Saima M Sidik
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA
| | - Diego Huet
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA
| | - Suresh M Ganesan
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - My-Hang Huynh
- Department of Microbiology and Immunology, University of Michigan School of Medicine, Ann Arbor, MI 48109, USA
| | - Tim Wang
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139 USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Armiyaw S Nasamu
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Prathapan Thiru
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA
| | - Jeroen P J Saeij
- Department of Pathology, Microbiology and Immunology, University of California, Davis, Davis, CA 95616, USA
| | - Vern B Carruthers
- Department of Microbiology and Immunology, University of Michigan School of Medicine, Ann Arbor, MI 48109, USA
| | - Jacquin C Niles
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Sebastian Lourido
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA.
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Skinner-Adams TS, Sumanadasa SD, Fisher GM, Davis RA, Doolan DL, Andrews KT. Defining the targets of antiparasitic compounds. Drug Discov Today 2016; 21:725-39. [DOI: 10.1016/j.drudis.2016.01.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Revised: 12/04/2015] [Accepted: 01/07/2016] [Indexed: 10/22/2022]
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de Koning-Ward TF, Gilson PR, Crabb BS. Advances in molecular genetic systems in malaria. Nat Rev Microbiol 2015; 13:373-87. [DOI: 10.1038/nrmicro3450] [Citation(s) in RCA: 91] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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Suzuki S, Tsukiyama T, Kaneko T, Imai H, Minami N. A hyperactive piggyBac transposon system is an easy-to-implement method for introducing foreign genes into mouse preimplantation embryos. J Reprod Dev 2015; 61:241-4. [PMID: 25740401 PMCID: PMC4498375 DOI: 10.1262/jrd.2014-157] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Accepted: 01/06/2015] [Indexed: 02/02/2023] Open
Abstract
Transgenic mice are important tools for genetic analysis. A current prominent method for producing transgenic mice involves pronuclear microinjection into 1-cell embryos. However, the total transgenic efficiency obtained using this method is less than 10%. Here, we demonstrate that highly efficient transgenesis in mice can be achieved by cytoplasmic microinjection using a hyperactive piggyBac system. In embryos in which hyPBase mRNA and pPB-CAG-TagRFP DNA were co-injected into the cytoplasm, TagRFP fluorescence was observed after the 2-cell stage; when 30 ng/µl pPB-CAG-TagRFP DNA and 30 ng/µl hyPBase mRNA were co-injected, 94.4% of blastocysts were TagRFP positive. Furthermore, a high concentration of hyPBase mRNA resulted in creation of mosaic embryos in which the TagRFP signals partially disappeared. However, suitable concentrations of injected DNA and hyPBase mRNA produced embryos in which almost all blastomeres were TagRFP positive. Thus, the hyperactive piggyBac transposon system is an easy-to-implement and highly effective method that can contribute to production of transgenic mice.
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Affiliation(s)
- Shinnosuke Suzuki
- Laboratory of Reproductive Biology, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan
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Hong JB, Chou FJ, Ku AT, Fan HH, Lee TL, Huang YH, Yang TL, Su IC, Yu IS, Lin SW, Chien CL, Ho HN, Chen YT. A nucleolus-predominant piggyBac transposase, NP-mPB, mediates elevated transposition efficiency in mammalian cells. PLoS One 2014; 9:e89396. [PMID: 24586748 PMCID: PMC3933532 DOI: 10.1371/journal.pone.0089396] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2013] [Accepted: 01/20/2014] [Indexed: 11/25/2022] Open
Abstract
PiggyBac is a prevalent transposon system used to deliver transgenes and functionally explore the mammalian untouched genomic territory. The important features of piggyBac transposon are the relatively low insertion site preference and the ability of seamless removal from genome, which allow its potential uses in functional genomics and regenerative medicine. Efforts to increase its transposition efficiency in mammals were made through engineering the corresponding transposase (PBase) codon usage to enhance its expression level and through screening for mutant PBase variants with increased enzyme activity. To improve the safety for its potential use in regenerative medicine applications, site-specific transposition was achieved by using engineered zinc finger- and Gal4-fused PBases. An excision-prone PBase variant has also been successfully developed. Here we describe the construction of a nucleolus-predominant PBase, NP-mPB, by adding a nucleolus-predominant (NP) signal peptide from HIV-1 TAT protein to a mammalian codon-optimized PBase (mPB). Although there is a predominant fraction of the NP-mPB-tGFP fusion proteins concentrated in the nucleoli, an insertion site preference toward nucleolar organizer regions is not detected. Instead a 3–4 fold increase in piggyBac transposition efficiency is reproducibly observed in mouse and human cells.
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Affiliation(s)
- Jin-Bon Hong
- Graduate Institute of Medical Genomics and Proteomics, National Taiwan University College of Medicine, Taipei, Taiwan
- Department of Dermatology, National Taiwan University Hospital and College of Medicine, Taipei, Taiwan
| | - Fu-Ju Chou
- Graduate Institute of Medical Genomics and Proteomics, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Amy T. Ku
- Graduate Institute of Medical Genomics and Proteomics, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Hsiang-Hsuan Fan
- Graduate Institute of Medical Genomics and Proteomics, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Tung-Lung Lee
- Department of Dermatology, National Taiwan University Hospital and College of Medicine, Taipei, Taiwan
| | - Yung-Hsin Huang
- Department of Dermatology, National Taiwan University Hospital and College of Medicine, Taipei, Taiwan
| | - Tsung-Lin Yang
- Department of Otolaryngology, National Taiwan University Hospital and College of Medicine, Taipei, Taiwan
- Research Center for Developmental Biology and Regenerative Medicine, National Taiwan University, Taipei, Taiwan
| | - I-Chang Su
- Graduate Institute of Clinical Medicine, National Taiwan University College of Medicine, Taipei, Taiwan
| | - I-Shing Yu
- Transgenic Mouse Model Core Facility of the National Research Program for Genomic Medicine, National Taiwan University College of Medicine, Taipei, Taiwan
- Laboratory Animal Center, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Shu-Wha Lin
- Department of Clinical Laboratory Sciences and Medical Biotechnology, National Taiwan University College of Medicine, Taipei, Taiwan
- Department of Laboratory Medicine, National Taiwan University Hospital, Taipei, Taiwan
| | - Chung-Liang Chien
- Graduate Institute of Medical Genomics and Proteomics, National Taiwan University College of Medicine, Taipei, Taiwan
- Research Center for Developmental Biology and Regenerative Medicine, National Taiwan University, Taipei, Taiwan
- Stem Cell Core Laboratory, National Taiwan University Center of Genomic Medicine, National Taiwan University, Taipei, Taiwan
- Graduate Institute of Anatomy and Cell Biology, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Hong-Nerng Ho
- Graduate Institute of Medical Genomics and Proteomics, National Taiwan University College of Medicine, Taipei, Taiwan
- Research Center for Developmental Biology and Regenerative Medicine, National Taiwan University, Taipei, Taiwan
- Stem Cell Core Laboratory, National Taiwan University Center of Genomic Medicine, National Taiwan University, Taipei, Taiwan
- Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology, National Taiwan University Hospital and College of Medicine, Taipei, Taiwan
| | - You-Tzung Chen
- Graduate Institute of Medical Genomics and Proteomics, National Taiwan University College of Medicine, Taipei, Taiwan
- Research Center for Developmental Biology and Regenerative Medicine, National Taiwan University, Taipei, Taiwan
- Graduate Institute of Clinical Medicine, National Taiwan University College of Medicine, Taipei, Taiwan
- Stem Cell Core Laboratory, National Taiwan University Center of Genomic Medicine, National Taiwan University, Taipei, Taiwan
- Genome and Systems Biology Program, National Taiwan University, Taipei, Taiwan
- * E-mail:
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Cao Y, Rui B, Wellems DL, Li M, Chen B, Zhang D, Pan W. Identification of piggyBac-mediated insertions in Plasmodium berghei by next generation sequencing. Malar J 2013; 12:287. [PMID: 23961915 PMCID: PMC3765144 DOI: 10.1186/1475-2875-12-287] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Accepted: 08/18/2013] [Indexed: 01/24/2023] Open
Abstract
Background The piggyBac transposon system provides a powerful forward genetics tool to study gene function in Plasmodium parasites via random insertion mutagenesis and phenotypic screening. The identification of genotype of piggyBac mutants in the Plasmodium genome is thus an indispensable step in forward genetic analysis. Several PCR-based approaches have been used to identify the piggyBac insertion sites in Plasmodium falciparum and Plasmodium berghei, but all are tedious and inefficient. Next generation sequencing can produce large amounts of sequence data and is particularly suitable for genome-wide association studies. In this study, the Next generation sequencing technology was employed to efficiently identify piggyBac insertion sites in the genome of P. berghei. Methods Plasmodium berghei parasites were co-transfected with piggyBac donor and helper plasmids. Initially, the classical inverse PCR method was used to identify the existence of piggyBac insertions in the P. berghei genome. The whole genome of post-transfection parasites was subsequently sequenced with a PCR-free paired-end module using the Illumina HiSeq sequencing system. The two distinct methods (‘BLAST method’ and ‘SOAP method’) were employed to identify piggyBac insertion sites in the P. berghei genome with Illumina sequencing data. All the identified piggyBac insertions were further tested by half-nested PCR. Results The inverse PCR method resulted in a very low yield of ten individual insertions identified. Conversely, 47 piggyBac insertions were identified from about 1 Gb of Illumina sequencing data via the two distinct analysis methods. The majority of identified piggyBac insertions were confirmed by half-nested PCR. In addition, 1,850 single nucleotide polymorphisms were identified through alignment of the Illumina sequencing data of the P. berghei ANKA strain used in this study with the reference genome sequences. Conclusion This study demonstrates that a high-throughput genome sequencing approach is an efficient tool for the identification of piggyBac-mediated insertions in Plasmodium parasites.
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Affiliation(s)
- Yi Cao
- Department of Tropical Infectious Diseases, Second Military Medical University, Shanghai, China
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