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Trajano-Silva LAM, Mule SN, Palmisano G. Molecular tools to regulate gene expression in Trypanosoma cruzi. Adv Clin Chem 2024; 120:169-190. [PMID: 38762241 DOI: 10.1016/bs.acc.2024.04.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/20/2024]
Abstract
Developing molecular strategies to manipulate gene expression in trypanosomatids is challenging, particularly with respect to the unique gene expression mechanisms adopted by these unicellular parasites, such as polycistronic mRNA transcription and multi-gene families. In the case of Trypanosoma cruzi (T. cruzi), the causative agent of Chagas Disease, the lack of RNA interference machinery further complicated functional genetic studies important for understanding parasitic biology and developing biomarkers and potential therapeutic targets. Therefore, alternative methods of performing knockout and/or endogenous labelling experiments were developed to identify and understand the function of proteins for survival and interaction with the host. In this review, we present the main tools for the genetic manipulation of T. cruzi, focusing on the Clustered Regularly Interspaced Short Palindromic Repeats Cas9-associated system technique widely used in this organism. Moreover, we highlight the importance of using these tools to elucidate the function of uncharacterized and glycosylated proteins. Further developments of these technologies will allow the identification of new biomarkers, therapeutic targets and potential vaccines against Chagas disease with greater efficiency and speed.
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Affiliation(s)
- Lays Adrianne M Trajano-Silva
- Glycoproteomic Laboratory, Parasitology Department, Institute of Biomedical Science II, University of Sao Paulo, Sao Paulo, Brazil
| | - Simon Ngao Mule
- Glycoproteomic Laboratory, Parasitology Department, Institute of Biomedical Science II, University of Sao Paulo, Sao Paulo, Brazil
| | - Giuseppe Palmisano
- Glycoproteomic Laboratory, Parasitology Department, Institute of Biomedical Science II, University of Sao Paulo, Sao Paulo, Brazil; School of Natural Sciences, Macquarie University, Sydney, NSW, Australia.
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2
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Romagnoli BAA, Lucena ACR, Freire ER, Munhoz da Rocha IF, Alves LR, Goldenberg S. TcZC3HTTP, a regulatory element that contributes to Trypanosoma cruzi cell proliferation. Microbiol Spectr 2024; 12:e0288023. [PMID: 38270449 PMCID: PMC10913370 DOI: 10.1128/spectrum.02880-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Accepted: 12/04/2023] [Indexed: 01/26/2024] Open
Abstract
Post-transcriptional regulation of gene expression is a critical process for adapting to and surviving Trypanosoma cruzi, a parasite with a complex life cycle. RNA-binding proteins (RBPs) are key players in this regulation, forming ribonucleoprotein complexes (messenger ribonucleoproteins) and RNA granules that control transcript stability, localization, degradation, and translation modulation. Understanding the specific roles of individual RBPs is crucial for unraveling the details of this regulatory network. In this study, we generated null mutants of the TcZC3HTTP gene, a specific RBP in the Trypanosoma family characterized by a C3H zinc finger and a DNAJ domain associated with RNA and protein binding, respectively. Through cell growth assays, we demonstrated that the absence of TcZC3HTTP or the expression of an additional tagged version impacted epimastigote growth, indicating its contribution to cell proliferation. TcZC3HTTP was found to associate with mRNAs involved in cell cycle and division in epimastigotes, while in nutritionally stressed parasites it exhibited associations with mRNAs coding for other RBPs and rRNA. Furthermore, our analysis identified that TcZC3HTTP protein partners were different during normal growth conditions compared to starvation conditions, with the latter showing enrichment of ribosomal proteins and other RBPs. Therefore, this study provides insights into TcZC3HTTP's role in the post-transcriptional regulation of gene expression during normal growth and nutritional stress in T. cruzi, uncovering its versatile functions in different cellular contexts.IMPORTANCEUnderstanding how Trypanosoma cruzi, the causative agent of Chagas disease, regulates gene expression is crucial for developing targeted interventions. In this study, we investigated the role of TcZC3HTTP, an RNA-binding protein, in post-transcriptional regulation. Our findings demonstrate that TcZC3HTTP is relevant for the growth and proliferation of epimastigotes, a stage of the parasite's life cycle. We identified its associations with specific mRNAs involved in cell cycle and division and its interactions with enzymes and other RNA-binding proteins (RBPs) under normal and starvation conditions. These insights shed light on the regulatory network underlying gene expression in T. cruzi and reveal the multifaceted functions of RBPs in this parasite. Such knowledge enhances our understanding of the parasite's biology and opens avenues for developing novel therapeutic strategies targeting post-transcriptional gene regulation in T. cruzi.
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Affiliation(s)
| | - Aline Castro Rodrigues Lucena
- Laboratory for Applied Science and Technology in Health, Carlos Chagas Institute, Fiocruz PR, Curitiba, Paraná, Brazil
| | - Eden Ribeiro Freire
- Gene Expression Regulation Laboratory, Carlos Chagas Institute, Fiocruz PR, Curitiba, Paraná, Brazil
| | | | - Lysangela Ronalte. Alves
- Gene Expression Regulation Laboratory, Carlos Chagas Institute, Fiocruz PR, Curitiba, Paraná, Brazil
- Research Center in Infectious Diseases, Division of Infectious Disease and Immunity, CHU de Quebec Research Center, University Laval, Quebec, Canada
| | - Samuel Goldenberg
- Gene Expression Regulation Laboratory, Carlos Chagas Institute, Fiocruz PR, Curitiba, Paraná, Brazil
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3
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Efficient CRISPR-Cas9-mediated genome editing for characterization of essential genes in Trypanosoma cruzi. STAR Protoc 2022; 3:101324. [PMID: 35496799 PMCID: PMC9048117 DOI: 10.1016/j.xpro.2022.101324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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4
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Saenz-Garcia JL, Borges BS, Souza-Melo N, Machado LV, Miranda JS, Pacheco-Lugo LA, Moretti NS, Wheleer R, Soares Medeiros LC, DaRocha WD. Trypanin Disruption Affects the Motility and Infectivity of the Protozoan Trypanosoma cruzi. Front Cell Infect Microbiol 2022; 11:807236. [PMID: 35071054 PMCID: PMC8777028 DOI: 10.3389/fcimb.2021.807236] [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: 11/01/2021] [Accepted: 12/09/2021] [Indexed: 11/13/2022] Open
Abstract
The flagellum of Trypanosomatids is an organelle that contributes to multiple functions, including motility, cell division, and host–pathogen interaction. Trypanin was first described in Trypanosoma brucei and is part of the dynein regulatory complex. TbTrypanin knockdown parasites showed motility defects in procyclic forms; however, silencing in bloodstream forms was lethal. Since TbTrypanin mutants show drastic phenotypic changes in mammalian stages, we decided to evaluate if the Trypanosoma cruzi ortholog plays a similar role by using the CRISPR-Cas9 system to generate null mutants. A ribonucleoprotein complex of SaCas9 and sgRNA plus donor oligonucleotide were used to edit both alleles of TcTrypanin without any selectable marker. TcTrypanin −/− epimastigotes showed a lower growth rate, partially detached flagella, normal numbers of nuclei and kinetoplasts, and motility defects such as reduced displacement and speed and increased tumbling propensity. The epimastigote mutant also showed decreased efficiency of in-vitro metacyclogenesis. Mutant parasites were able to complete the entire life cycle in vitro; however, they showed a reduction in their infection capacity compared with WT and addback cultures. Our data show that T. cruzi life cycle stages have differing sensitivities to TcTrypanin deletion. In conclusion, additional work is needed to dissect the motility components of T. cruzi and to identify essential molecules for mammalian stages.
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Affiliation(s)
- Jose L Saenz-Garcia
- Laboratório de Genômica Funcional de Parasitos (GFP), Universidade Federal de Paraná, Curitiba, Brazil
| | - Beatriz S Borges
- Laboratório de Biologia Celular, Instituto Carlos Chagas, Fundação Oswaldo Cruz (Fiocruz), Curitiba, Brazil
| | - Normanda Souza-Melo
- Laboratório de Biologia Molecular de Patógenos (LBMP), Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil.,Laboratório de Ultraestrutura Hertha Mayer, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
| | - Luiz V Machado
- Laboratório de Genômica Funcional de Parasitos (GFP), Universidade Federal de Paraná, Curitiba, Brazil
| | - Juliana S Miranda
- Laboratório de Genômica Funcional de Parasitos (GFP), Universidade Federal de Paraná, Curitiba, Brazil
| | | | - Nilmar S Moretti
- Laboratório de Biologia Molecular de Patógenos (LBMP), Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Richard Wheleer
- Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Lia C Soares Medeiros
- Laboratório de Biologia Celular, Instituto Carlos Chagas, Fundação Oswaldo Cruz (Fiocruz), Curitiba, Brazil
| | - Wanderson D DaRocha
- Laboratório de Genômica Funcional de Parasitos (GFP), Universidade Federal de Paraná, Curitiba, Brazil
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5
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Marek M, Ramos-Morales E, Picchi-Constante GFA, Bayer T, Norström C, Herp D, Sales-Junior PA, Guerra-Slompo EP, Hausmann K, Chakrabarti A, Shaik TB, Merz A, Troesch E, Schmidtkunz K, Goldenberg S, Pierce RJ, Mourão MM, Jung M, Schultz J, Sippl W, Zanchin NIT, Romier C. Species-selective targeting of pathogens revealed by the atypical structure and active site of Trypanosoma cruzi histone deacetylase DAC2. Cell Rep 2021; 37:110129. [PMID: 34936867 DOI: 10.1016/j.celrep.2021.110129] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Revised: 10/26/2021] [Accepted: 11/23/2021] [Indexed: 01/12/2023] Open
Abstract
Writing and erasing of posttranslational modifications are crucial to phenotypic plasticity and antigenic variation of eukaryotic pathogens. Targeting pathogens' modification machineries, thus, represents a valid approach to fighting parasitic diseases. However, identification of parasitic targets and the development of selective anti-parasitic drugs still represent major bottlenecks. Here, we show that the zinc-dependent histone deacetylases (HDACs) of the protozoan parasite Trypanosoma cruzi are key regulators that have significantly diverged from their human counterparts. Depletion of T. cruzi class I HDACs tcDAC1 and tcDAC2 compromises cell-cycle progression and division, leading to cell death. Notably, tcDAC2 displays a deacetylase activity essential to the parasite and shows major structural differences with human HDACs. Specifically, tcDAC2 harbors a modular active site with a unique subpocket targeted by inhibitors showing substantial anti-parasitic effects in cellulo and in vivo. Thus, the targeting of the many atypical HDACs in pathogens can enable anti-parasitic selective chemical impairment.
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Affiliation(s)
- Martin Marek
- Université de Strasbourg, CNRS, INSERM, Institut de Génétique et de Biologie Moléculaire et Cellulaire, UMR 7104, U 1258, 67404 Illkirch, France; IGBMC, Department of Integrated Structural Biology, 1 rue Laurent Fries, B.P. 10142, 67404 Illkirch Cedex, France
| | - Elizabeth Ramos-Morales
- Université de Strasbourg, CNRS, INSERM, Institut de Génétique et de Biologie Moléculaire et Cellulaire, UMR 7104, U 1258, 67404 Illkirch, France; IGBMC, Department of Integrated Structural Biology, 1 rue Laurent Fries, B.P. 10142, 67404 Illkirch Cedex, France
| | | | - Theresa Bayer
- Institute of Pharmacy, Martin-Luther-Universität Halle-Wittenberg, Wolfgang-Langenbeck-Straße 4, 06120 Halle/Saale, Germany
| | | | - Daniel Herp
- Institute of Pharmaceutical Sciences, Albert-Ludwigs-Universität Freiburg, Albertstraße 25, 79104 Freiburg, Germany
| | - Policarpo A Sales-Junior
- Instituto René Rachou, Fundação Oswaldo Cruz, Avenida Augusto de Lima, 1715, 30190-002 Belo Horizonte, Brazil
| | | | - Kristin Hausmann
- Institute of Pharmacy, Martin-Luther-Universität Halle-Wittenberg, Wolfgang-Langenbeck-Straße 4, 06120 Halle/Saale, Germany
| | - Alokta Chakrabarti
- Institute of Pharmaceutical Sciences, Albert-Ludwigs-Universität Freiburg, Albertstraße 25, 79104 Freiburg, Germany
| | - Tajith B Shaik
- Université de Strasbourg, CNRS, INSERM, Institut de Génétique et de Biologie Moléculaire et Cellulaire, UMR 7104, U 1258, 67404 Illkirch, France; IGBMC, Department of Integrated Structural Biology, 1 rue Laurent Fries, B.P. 10142, 67404 Illkirch Cedex, France
| | - Annika Merz
- Institute of Pharmaceutical Sciences, Albert-Ludwigs-Universität Freiburg, Albertstraße 25, 79104 Freiburg, Germany
| | - Edouard Troesch
- Université de Strasbourg, CNRS, INSERM, Institut de Génétique et de Biologie Moléculaire et Cellulaire, UMR 7104, U 1258, 67404 Illkirch, France; IGBMC, Department of Integrated Structural Biology, 1 rue Laurent Fries, B.P. 10142, 67404 Illkirch Cedex, France
| | - Karin Schmidtkunz
- Institute of Pharmaceutical Sciences, Albert-Ludwigs-Universität Freiburg, Albertstraße 25, 79104 Freiburg, Germany
| | - Samuel Goldenberg
- Instituto Carlos Chagas, Fiocruz Paraná, Curitiba, Paraná 81350-010, Brazil
| | - Raymond J Pierce
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 9017 - CIIL -Centre d'Infection et d'Immunité de Lille, 59000 Lille, France
| | - Marina M Mourão
- Instituto René Rachou, Fundação Oswaldo Cruz, Avenida Augusto de Lima, 1715, 30190-002 Belo Horizonte, Brazil
| | - Manfred Jung
- Institute of Pharmaceutical Sciences, Albert-Ludwigs-Universität Freiburg, Albertstraße 25, 79104 Freiburg, Germany
| | - Johan Schultz
- Kancera AB, Nanna Svartz Väg 4, SE-17165 Solna, Sweden
| | - Wolfgang Sippl
- Institute of Pharmacy, Martin-Luther-Universität Halle-Wittenberg, Wolfgang-Langenbeck-Straße 4, 06120 Halle/Saale, Germany
| | - Nilson I T Zanchin
- Instituto Carlos Chagas, Fiocruz Paraná, Curitiba, Paraná 81350-010, Brazil.
| | - Christophe Romier
- Université de Strasbourg, CNRS, INSERM, Institut de Génétique et de Biologie Moléculaire et Cellulaire, UMR 7104, U 1258, 67404 Illkirch, France; IGBMC, Department of Integrated Structural Biology, 1 rue Laurent Fries, B.P. 10142, 67404 Illkirch Cedex, France.
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6
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Picchi-Constante GFA, Guerra-Slompo EP, Tahira AC, Alcantara MV, Amaral MS, Ferreira AS, Batista M, Batista CM, Goldenberg S, Verjovski-Almeida S, Zanchin NIT. Metacyclogenesis defects and gene expression hallmarks of histone deacetylase 4-deficient Trypanosoma cruzi cells. Sci Rep 2021; 11:21671. [PMID: 34737385 PMCID: PMC8569148 DOI: 10.1038/s41598-021-01080-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 10/18/2021] [Indexed: 12/13/2022] Open
Abstract
Trypanosoma cruzi—the causative agent of Chagas disease—like other kinetoplastids, relies mostly on post-transcriptional mechanisms for regulation of gene expression. However, trypanosomatids undergo drastic changes in nuclear architecture and chromatin structure along their complex life cycle which, combined with a remarkable set of reversible histone post-translational modifications, indicate that chromatin is also a target for control of gene expression and differentiation signals in these organisms. Chromatin-modifying enzymes have a direct impact on gene expression programs and DNA metabolism. In this work, we have investigated the function of T. cruzi histone deacetylase 4 (TcHDAC4). We show that, although TcHDAC4 is not essential for viability, metacyclic trypomastigote TcHDAC4 null mutants show a thin cell body and a round and less condensed nucleus located very close to the kinetoplast. Sixty-four acetylation sites were quantitatively evaluated, which revealed H2AT85ac, H4K10ac and H4K78ac as potential target sites of TcHDAC4. Gene expression analyses identified three chromosomes with overrepresented regions of differentially expressed genes in the TcHDAC4 knockout mutant compared with the wild type, showing clusters of either up or downregulated genes. The adjacent chromosomal location of some of these genes indicates that TcHDAC4 participates in gene expression regulation during T. cruzi differentiation.
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Affiliation(s)
| | | | - Ana Carolina Tahira
- Laboratório de Parasitologia, Instituto Butantan, São Paulo, SP, 05503-900, Brazil
| | | | - Murilo Sena Amaral
- Laboratório de Parasitologia, Instituto Butantan, São Paulo, SP, 05503-900, Brazil
| | | | - Michel Batista
- Instituto Carlos Chagas, Fiocruz Paraná, Curitiba, Paraná, 81350-010, Brazil
| | | | - Samuel Goldenberg
- Instituto Carlos Chagas, Fiocruz Paraná, Curitiba, Paraná, 81350-010, Brazil
| | - Sergio Verjovski-Almeida
- Laboratório de Parasitologia, Instituto Butantan, São Paulo, SP, 05503-900, Brazil.,Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, SP, 05508-900, Brazil
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7
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Chagas Cardiomyopathy: From Romaña Sign to Heart Failure and Sudden Cardiac Death. Pathogens 2021; 10:pathogens10050505. [PMID: 33922366 PMCID: PMC8145478 DOI: 10.3390/pathogens10050505] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 04/10/2021] [Accepted: 04/13/2021] [Indexed: 12/16/2022] Open
Abstract
Despite nearly a century of research and accounting for the highest disease burden of any parasitic disease in the Western Hemisphere, Chagas disease (CD) is still a challenging diagnosis, primarily due to its poor recognition outside of Latin America. Although initially considered endemic to Central and South America, globalization, urbanization, and increased migration have spread the disease worldwide in the last few years, making it a significant public health threat. The international medical community’s apparent lack of interest in this disease that was previously thought to be geographically restricted has delayed research on the complex host–parasite relationship that determines myocardial involvement and its differential behavior from other forms of cardiomyopathy, particularly regarding treatment strategies. Multiple cellular and molecular mechanisms that contribute to degenerative, inflammatory, and fibrotic myocardial responses have been identified and warrant further research to expand the therapeutic arsenal and impact the high burden attributed to CD. Altogether, cardiac dysautonomia, microvascular disturbances, parasite-mediated myocardial damage, and chronic immune-mediated injury are responsible for the disease’s clinical manifestations, ranging from asymptomatic disease to severe cardiac and gastrointestinal involvement. It is crucial for healthcare workers to better understand CD transmission and disease dynamics, including its behavior on both its acute and chronic phases, to make adequate and evidence-based decisions regarding the disease. This review aims to summarize the most recent information on the epidemiology, pathogenesis, clinical presentation, diagnosis, screening, and treatment of CD, emphasizing on Chagasic cardiomyopathy’s (Ch-CMP) clinical presentation and pathobiological mechanisms leading to sudden cardiac death.
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Kirti A, Sharma M, Rani K, Bansal A. CRISPRing protozoan parasites to better understand the biology of diseases. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2021; 180:21-68. [PMID: 33934837 DOI: 10.1016/bs.pmbts.2021.01.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Precise gene editing techniques are paramount to gain deeper insights into the biological processes such as host-parasite interactions, drug resistance mechanisms, and gene-function relationships. Discovery of CRISPR-Cas9 system has spearheaded mechanistic understanding of protozoan parasite biology as evident from the number of reports in the last decade. Here, we have described the use of CRISPR-Cas9 in understanding the biology of medically important protozoan parasites such as Plasmodium, Leishmania, Trypanosoma, Babesia and Trichomonas. In spite of intrinsic difficulties in genome editing in these protozoan parasites, CRISPR-Cas9 has acted as a catalyst for faster generation of desired transgenic parasites. Modifications in the CRISPR-Cas9 system for improving the efficiency have been useful in better understanding the molecular mechanisms associated with repair of double strand breaks in the parasites. Moreover, improvement in reagents used for CRISPR mediated gene editing have been instrumental in addressing the issue of non-specificity and toxicity for therapeutic use. These application-based modifications may help in further increasing the efficiency of gene editing in protozoan parasites.
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Affiliation(s)
- Apurva Kirti
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Manish Sharma
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Komal Rani
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Abhisheka Bansal
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India.
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9
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Yagoubat A, Corrales RM, Bastien P, Lévêque MF, Sterkers Y. Gene Editing in Trypanosomatids: Tips and Tricks in the CRISPR-Cas9 Era. Trends Parasitol 2020; 36:745-760. [DOI: 10.1016/j.pt.2020.06.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 06/19/2020] [Accepted: 06/30/2020] [Indexed: 12/22/2022]
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10
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Pacheco-Lugo LA, Sáenz-García JL, Díaz-Olmos Y, Netto-Costa R, Brant RSC, DaRocha WD. CREditing: a tool for gene tuning in Trypanosoma cruzi. Int J Parasitol 2020; 50:1067-1077. [PMID: 32858036 DOI: 10.1016/j.ijpara.2020.06.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 05/31/2020] [Accepted: 06/02/2020] [Indexed: 12/30/2022]
Abstract
The genetic manipulation of Trypanosoma cruzi continues to be a challenge, mainly due to the lack of available and efficient molecular tools. The CRE-lox recombination system is a site-specific recombinase technology, widely used method of achieving conditional targeted deletions, inversions, insertions, gene activation, translocation, and other modifications in chromosomal or episomal DNA. In the present study, the CRE-lox system was adapted to expand the current genetic toolbox for this hard-to-manipulate parasite. For this, evaluations of whether direct protein delivery of CRE recombinase through electroporation could improve CRE-mediated recombination in T. cruzi were performed. CRE recombinase was fused to the C-terminus of T. cruzi histone H2B, which carries the nuclear localization signal and is expressed in the prokaryotic system. The fusion protein was affinity purified and directly introduced into epimastigotes and tissue culture-derived trypomastigotes. This enabled the control of gene expression as demonstrated by turning on a tandem dimer fluorescent protein reporter gene that had been previously transfected into parasites, achieving CRE-mediated recombination in up to 85% of parasites. This system was further tested for its ability to turn off gene expression, remove selectable markers integrated into the genome, and conditionally knock down the nitroreductase gene, which is involved in drug resistance. Additionally, CREditing also enabled the control of gene expression in tissue culture trypomastigotes, which are more difficult to transfect than epimastigotes. The considerable advances in genomic manipulation of T. cruzi shown in this study can be used by others to aid in the greater understanding of this parasite through gain- or loss-of-function approaches.
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Affiliation(s)
- Lisandro A Pacheco-Lugo
- Laboratório de Genômica Funcional de Parasitos (GFP), Universidade Federal de Paraná, Paraná, Brazil; Facultad de Ciencias Básicas Biomédicas, Universidad Simón Bolívar, Barranquilla, Colombia
| | - José L Sáenz-García
- Laboratório de Genômica Funcional de Parasitos (GFP), Universidade Federal de Paraná, Paraná, Brazil
| | - Yirys Díaz-Olmos
- Instituto Carlos Chagas, Fiocruz-Paraná, Paraná, Brazil; Facultad de Ciencias de la Salud, Universidad del Norte, Barranquilla, Colombia
| | | | - Rodrigo S C Brant
- Laboratório de Genômica Funcional de Parasitos (GFP), Universidade Federal de Paraná, Paraná, Brazil
| | - Wanderson D DaRocha
- Laboratório de Genômica Funcional de Parasitos (GFP), Universidade Federal de Paraná, Paraná, Brazil.
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11
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Lander N, Cruz-Bustos T, Docampo R. A CRISPR/Cas9-riboswitch-Based Method for Downregulation of Gene Expression in Trypanosoma cruzi. Front Cell Infect Microbiol 2020; 10:68. [PMID: 32175288 PMCID: PMC7056841 DOI: 10.3389/fcimb.2020.00068] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Accepted: 02/11/2020] [Indexed: 12/18/2022] Open
Abstract
Few genetic tools were available to work with Trypanosoma cruzi until the recent introduction of the CRISPR/Cas9 technique for gene knockout, gene knock-in, gene complementation, and endogenous gene tagging. Riboswitches are naturally occurring self-cleaving RNAs (ribozymes) that can be ligand-activated. Results from our laboratory recently demonstrated the usefulness of the glmS ribozyme from Bacillus subtilis, which has been shown to control reporter gene expression in response to exogenous glucosamine, for gene silencing in Trypanosoma brucei. In this work we used the CRISPR/Cas9 system for endogenously tagging T. cruzi glycoprotein 72 (TcGP72) and vacuolar proton pyrophosphatase (TcVP1) with the active (glmS) or inactive (M9) ribozyme. Gene tagging was confirmed by PCR and protein downregulation was verified by western blot analyses. Further phenotypic characterization was performed by immunofluorescence analysis and quantification of growth in vitro. Our results indicate that the method was successful in silencing the expression of both genes without the need of glucosamine in the medium, suggesting that T. cruzi produces enough levels of endogenous glucosamine 6-phosphate to stimulate the glmS ribozyme activity under normal growth conditions. This method could be useful to obtain knockdowns of essential genes in T. cruzi and to validate potential drug targets in this parasite.
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Affiliation(s)
- Noelia Lander
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, United States
| | - Teresa Cruz-Bustos
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, United States
| | - Roberto Docampo
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, United States.,Department of Cellular Biology, University of Georgia, Athens, GA, United States
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12
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Romagnoli BAA, Holetz FB, Alves LR, Goldenberg S. RNA Binding Proteins and Gene Expression Regulation in Trypanosoma cruzi. Front Cell Infect Microbiol 2020; 10:56. [PMID: 32154189 PMCID: PMC7045066 DOI: 10.3389/fcimb.2020.00056] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Accepted: 02/03/2020] [Indexed: 01/24/2023] Open
Abstract
The regulation of gene expression in trypanosomatids occurs mainly at the post-transcriptional level. In the case of Trypanosoma cruzi, the characterization of messenger ribonucleoprotein (mRNP) particles has allowed the identification of several classes of RNA binding proteins (RBPs), as well as non-canonical RBPs, associated with mRNA molecules. The protein composition of the mRNPs as well as the localization and functionality of the mRNAs depend on their associated proteins. mRNPs can also be organized into larger complexes forming RNA granules, which function as stress granules or P-bodies depending on the associated proteins. The fate of mRNAs in the cell, and consequently the genes expressed, depends on the set of proteins associated with the messenger molecule. These proteins allow the coordinated expression of mRNAs encoding proteins that are related in function, resulting in the formation of post-transcriptional operons. However, the puzzle posed by the combinatorial association of sets of RBPs with mRNAs and how this relates to the expressed genes remain to be elucidated. One important tool in this endeavor is the use of the CRISPR/CAS system to delete genes encoding RBPs, allowing the evaluation of their effect on the formation of mRNP complexes and associated mRNAs in the different compartments of the translation machinery. Accordingly, we recently established this methodology for T. cruzi and deleted the genes encoding RBPs containing zinc finger domains. In this manuscript, we will discuss the data obtained and the potential of the CRISPR/CAS methodology to unveil the role of RBPs in T. cruzi gene expression regulation.
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Affiliation(s)
- Bruno A A Romagnoli
- Gene Expression Regulation Laboratory, Institute Carlos Chagas, Curitiba, Brazil
| | - Fabiola B Holetz
- Gene Expression Regulation Laboratory, Institute Carlos Chagas, Curitiba, Brazil
| | - Lysangela R Alves
- Gene Expression Regulation Laboratory, Institute Carlos Chagas, Curitiba, Brazil
| | - Samuel Goldenberg
- Gene Expression Regulation Laboratory, Institute Carlos Chagas, Curitiba, Brazil
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Cordeiro AT. NADPH Producing Enzymes as Promising Drug Targets for Chagas Disease. Curr Med Chem 2019; 26:6564-6571. [PMID: 30306853 DOI: 10.2174/0929867325666181009152844] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 09/10/2018] [Accepted: 09/19/2018] [Indexed: 11/22/2022]
Abstract
Reduced Nicotinamide Adenine Dinucleotide Phosphate (NADPH) is a cofactor used in different anabolic reactions, such as lipid and nucleic acid synthesis, and for oxidative stress defense. NADPH is essential for parasite growth and viability. In trypanosomatid parasites, NADPH is supplied by the oxidative branch of the pentose phosphate pathway and by enzymes associated with the citric acid cycle. The present article will review recent achievements that suggest glucose-6-phosphate dehydrogenase and the cytosolic isoform of the malic enzyme as promising drug targets for the discovery of new drugs against Trypanosoma cruzi and T. brucei. Topics involving an alternative strategy in accelerating T. cruzi drug-target validation and the concept of drug-target classification will also be revisited.
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Affiliation(s)
- Artur T Cordeiro
- Brazilian Bioscience National Laboratory, Brazilian Center for Research in Energy and Materials, Campinas- SP, Brazil
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14
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Saavedra E, González-Chávez Z, Moreno-Sánchez R, Michels PA. Drug Target Selection for Trypanosoma cruzi Metabolism by Metabolic Control Analysis and Kinetic Modeling. Curr Med Chem 2019; 26:6652-6671. [DOI: 10.2174/0929867325666180917104242] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 08/17/2018] [Accepted: 08/17/2018] [Indexed: 11/22/2022]
Abstract
In the search for therapeutic targets in the intermediary metabolism of trypanosomatids
the gene essentiality criterion as determined by using knock-out and knock-down genetic
strategies is commonly applied. As most of the evaluated enzymes/transporters have
turned out to be essential for parasite survival, additional criteria and approaches are clearly
required for suitable drug target prioritization. The fundamentals of Metabolic Control
Analysis (MCA; an approach in the study of control and regulation of metabolism) and kinetic
modeling of metabolic pathways (a bottom-up systems biology approach) allow quantification
of the degree of control that each enzyme exerts on the pathway flux (flux control coefficient)
and metabolic intermediate concentrations (concentration control coefficient). MCA
studies have demonstrated that metabolic pathways usually have two or three enzymes with
the highest control of flux; their inhibition has more negative effects on the pathway function
than inhibition of enzymes exerting low flux control. Therefore, the enzymes with the highest
pathway control are the most convenient targets for therapeutic intervention. In this review,
the fundamentals of MCA as well as experimental strategies to determine the flux control coefficients
and metabolic modeling are analyzed. MCA and kinetic modeling have been applied
to trypanothione metabolism in Trypanosoma cruzi and the model predictions subsequently
validated in vivo. The results showed that three out of ten enzyme reactions analyzed
in the T. cruzi anti-oxidant metabolism were the most controlling enzymes. Hence, MCA and
metabolic modeling allow a further step in target prioritization for drug development against
trypanosomatids and other parasites.
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Affiliation(s)
- Emma Saavedra
- Departamento de Bioquimica, Instituto Nacional de Cardiologia Ignacio Chavez. Mexico City, Mexico
| | - Zabdi González-Chávez
- Departamento de Bioquimica, Instituto Nacional de Cardiologia Ignacio Chavez. Mexico City, Mexico
| | - Rafael Moreno-Sánchez
- Departamento de Bioquimica, Instituto Nacional de Cardiologia Ignacio Chavez. Mexico City, Mexico
| | - Paul A.M. Michels
- Centre for Immunity, Infection and Evolution (CIIE) and Centre for Translational and Chemical Biology (CTCB), School of Biological Sciences, The University of Edinburgh, Edinburgh, Scotland
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Salas-Sarduy E, Niemirowicz GT, José Cazzulo J, Alvarez VE. Target-based Screening of the Chagas Box: Setting Up Enzymatic Assays to Discover Specific Inhibitors Across Bioactive Compounds. Curr Med Chem 2019; 26:6672-6686. [PMID: 31284853 DOI: 10.2174/0929867326666190705160637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 09/10/2018] [Accepted: 11/07/2018] [Indexed: 11/22/2022]
Abstract
Chagas disease is a neglected tropical illness caused by the protozoan parasite Trypanosoma cruzi. The disease is endemic in Latin America with about 6 million people infected and many more being at risk. Only two drugs are available for treatment, Nifurtimox and Benznidazole, but they have a number of side effects and are not effective in all cases. This makes urgently necessary the development of new drugs, more efficient, less toxic and affordable to the poor people, who are most of the infected population. In this review we will summarize the current strategies used for drug discovery considering drug repositioning, phenotyping screenings and target-based approaches. In addition, we will describe in detail the considerations for setting up robust enzymatic assays aimed at identifying and validating small molecule inhibitors in high throughput screenings.
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Affiliation(s)
- Emir Salas-Sarduy
- Instituto de Investigaciones Biotecnologicas Dr. Rodolfo A. Ugalde - Instituto Tecnologico de Chascomus (IIB-INTECH), Universidad Nacional de San Martin (UNSAM) - Consejo Nacional de Investigaciones Cientificas y Técnicas (CONICET), Campus Miguelete, Av. 25 de Mayo y Francia, 1650 San Martin, Buenos Aires, Argentina
| | - Gabriela T Niemirowicz
- Instituto de Investigaciones Biotecnologicas Dr. Rodolfo A. Ugalde - Instituto Tecnologico de Chascomus (IIB-INTECH), Universidad Nacional de San Martin (UNSAM) - Consejo Nacional de Investigaciones Cientificas y Técnicas (CONICET), Campus Miguelete, Av. 25 de Mayo y Francia, 1650 San Martin, Buenos Aires, Argentina
| | - Juan José Cazzulo
- Instituto de Investigaciones Biotecnologicas Dr. Rodolfo A. Ugalde - Instituto Tecnologico de Chascomus (IIB-INTECH), Universidad Nacional de San Martin (UNSAM) - Consejo Nacional de Investigaciones Cientificas y Técnicas (CONICET), Campus Miguelete, Av. 25 de Mayo y Francia, 1650 San Martin, Buenos Aires, Argentina
| | - Vanina E Alvarez
- Instituto de Investigaciones Biotecnologicas Dr. Rodolfo A. Ugalde - Instituto Tecnologico de Chascomus (IIB-INTECH), Universidad Nacional de San Martin (UNSAM) - Consejo Nacional de Investigaciones Cientificas y Técnicas (CONICET), Campus Miguelete, Av. 25 de Mayo y Francia, 1650 San Martin, Buenos Aires, Argentina
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16
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Lander N, Chiurillo MA. State-of-the-art CRISPR/Cas9 Technology for Genome Editing in Trypanosomatids. J Eukaryot Microbiol 2019; 66:981-991. [PMID: 31211904 DOI: 10.1111/jeu.12747] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 06/12/2019] [Accepted: 06/12/2019] [Indexed: 12/23/2022]
Abstract
CRISPR/Cas9 technology has revolutionized biology. This prokaryotic defense system against foreign DNA has been repurposed for genome editing in a broad range of cell tissues and organisms. Trypanosomatids are flagellated protozoa belonging to the order Kinetoplastida. Some of its most representative members cause important human diseases affecting millions of people worldwide, such as Chagas disease, sleeping sickness and different forms of leishmaniases. Trypanosomatid infections represent an enormous burden for public health and there are no effective treatments for most of the diseases they cause. Since the emergence of the CRISPR/Cas9 technology, the genetic manipulation of these parasites has notably improved. As a consequence, genome editing is now playing a key role in the functional study of proteins, in the characterization of metabolic pathways, in the validation of alternative targets for antiparasitic interventions, and in the study of parasite biology and pathogenesis. In this work we review the different strategies that have been used to adapt the CRISPR/Cas9 system to Trypanosoma cruzi, Trypanosoma brucei, and Leishmania spp., as well as the research progress achieved using these approaches. Thereby, we will present the state-of-the-art molecular tools available for genome editing in trypanosomatids to finally point out the future perspectives in the field.
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Affiliation(s)
- Noelia Lander
- Center for Tropical and Emerging Global Diseases and Department of Cellular Biology, University of Georgia, Athens, Georgia, 30602
| | - Miguel A Chiurillo
- Center for Tropical and Emerging Global Diseases and Department of Cellular Biology, University of Georgia, Athens, Georgia, 30602
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17
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Overexpression of Trypanosoma cruzi High Mobility Group B protein (TcHMGB) alters the nuclear structure, impairs cytokinesis and reduces the parasite infectivity. Sci Rep 2019; 9:192. [PMID: 30655631 PMCID: PMC6336821 DOI: 10.1038/s41598-018-36718-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2018] [Accepted: 11/21/2018] [Indexed: 12/28/2022] Open
Abstract
Kinetoplastid parasites, included Trypanosoma cruzi, the causal agent of Chagas disease, present a unique genome organization and gene expression. Although they control gene expression mainly post-transcriptionally, chromatin accessibility plays a fundamental role in transcription initiation control. We have previously shown that High Mobility Group B protein from Trypanosoma cruzi (TcHMGB) can bind DNA in vitro. Here, we show that TcHMGB also acts as an architectural protein in vivo, since the overexpression of this protein induces changes in the nuclear structure, mainly the reduction of the nucleolus and a decrease in the heterochromatin:euchromatin ratio. Epimastigote replication rate was markedly reduced presumably due to a delayed cell cycle progression with accumulation of parasites in G2/M phase and impaired cytokinesis. Some functions involved in pathogenesis were also altered in TcHMGB-overexpressing parasites, like the decreased efficiency of trypomastigotes to infect cells in vitro, the reduction of intracellular amastigotes replication and the number of released trypomastigotes. Taken together, our results suggest that the TcHMGB protein is a pleiotropic player that controls cell phenotype and it is involved in key cellular processes.
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18
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Takagi Y, Akutsu Y, Doi M, Furukawa K. Utilization of proliferable extracellular amastigotes for transient gene expression, drug sensitivity assay, and CRISPR/Cas9-mediated gene knockout in Trypanosoma cruzi. PLoS Negl Trop Dis 2019; 13:e0007088. [PMID: 30640901 PMCID: PMC6347291 DOI: 10.1371/journal.pntd.0007088] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 01/25/2019] [Accepted: 12/18/2018] [Indexed: 12/21/2022] Open
Abstract
Trypanosoma cruzi has three distinct life cycle stages; epimastigote, trypomastigote, and amastigote. Amastigote is the replication stage in host mammalian cells, hence this stage of parasite has clinical significance in drug development research. Presence of extracellular amastigotes (EA) and their infection capability have been known for some decades. Here, we demonstrate that EA can be utilized as an axenic culture to aid in stage-specific study of T. cruzi. Amastigote-like property of axenic amastigote can be sustained in LIT medium at 37°C at least for 1 week, judging from their morphology, amastigote-specific UTR-regulated GFP expression, and stage-specific expression of selected endogenous genes. Inhibitory effect of benznidazole and nifurtimox on axenic amastigotes was comparable to that on intracellular amastigotes. Exogenous nucleic acids can be transfected into EA via conventional electroporation, and selective marker could be utilized for enrichment of transfectants. We also demonstrate that CRISPR/Cas9-mediated gene knockout can be performed in EA. Essentiality of the target gene can be evaluated by the growth capability of the knockout EA, either by continuation of axenic culturing or by host infection and following replication as intracellular amastigotes. By taking advantage of the accessibility and sturdiness of EA, we can potentially expand our experimental freedom in studying amastigote stage of T. cruzi.
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Affiliation(s)
- Yuko Takagi
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki, Japan
- * E-mail:
| | - Yukie Akutsu
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki, Japan
| | - Motomichi Doi
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki, Japan
| | - Koji Furukawa
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki, Japan
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19
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Abstract
The genetic manipulation of the human parasite Trypanosoma cruzi has been significantly improved since the implementation of the CRISPR/Cas9 system for genome editing in this organism. The system was initially used for gene knockout in T. cruzi, later on for endogenous gene tagging and more recently for gene complementation. Mutant cell lines obtained by CRISPR/Cas9 have been used for the functional characterization of proteins in different stages of this parasite's life cycle, including infective trypomastigotes and intracellular amastigotes. In this chapter we describe the methodology to achieve genome editing by CRISPR/Cas9 in T. cruzi. Our method involves the utilization of a template cassette (donor DNA) to promote double-strand break repair by homologous directed repair (HDR). In this way, we have generated homogeneous populations of genetically modified parasites in 4-5 weeks without the need of cell sorting, selection of clonal populations, or insertion of more than one resistance marker to modify both alleles of the gene. The methodology has been organized according to three main genetic purposes: gene knockout, gene complementation of knockout cell lines generated by CRISPR/Cas9, and C-terminal tagging of endogenous genes in T. cruzi. In addition, we refer to the specific results that have been published using each one of these strategies.
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20
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Rico E, Jeacock L, Kovářová J, Horn D. Inducible high-efficiency CRISPR-Cas9-targeted gene editing and precision base editing in African trypanosomes. Sci Rep 2018; 8:7960. [PMID: 29785042 PMCID: PMC5962531 DOI: 10.1038/s41598-018-26303-w] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Accepted: 05/09/2018] [Indexed: 12/21/2022] Open
Abstract
The Cas9 endonuclease can be programmed by guide RNA to introduce sequence-specific breaks in genomic DNA. Thus, Cas9-based approaches present a range of novel options for genome manipulation and precision editing. African trypanosomes are parasites that cause lethal human and animal diseases. They also serve as models for studies on eukaryotic biology, including 'divergent' biology. Genome modification, exploiting the native homologous recombination machinery, has been important for studies on trypanosomes but often requires multiple rounds of transfection using selectable markers that integrate at low efficiency. We report a system for delivering tetracycline inducible Cas9 and guide RNA to Trypanosoma brucei. In these cells, targeted DNA cleavage and gene disruption can be achieved at close to 100% efficiency without further selection. Disruption of aquaglyceroporin (AQP2) or amino acid transporter genes confers resistance to the clinical drugs pentamidine or eflornithine, respectively, providing simple and robust assays for editing efficiency. We also use the new system for homology-directed, precision base editing; a single-stranded oligodeoxyribonucleotide repair template was delivered to introduce a single AQP2 - T791G/L264R mutation in this case. The technology we describe now enables a range of novel programmed genome-editing approaches in T. brucei that would benefit from temporal control, high-efficiency and precision.
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Affiliation(s)
- Eva Rico
- Wellcome Trust Centre for Anti-Infectives Research, School of Life Sciences, University of Dundee, Dow Street, Dundee, DD1 5EH, UK
| | - Laura Jeacock
- Wellcome Trust Centre for Anti-Infectives Research, School of Life Sciences, University of Dundee, Dow Street, Dundee, DD1 5EH, UK
| | - Julie Kovářová
- Wellcome Trust Centre for Anti-Infectives Research, School of Life Sciences, University of Dundee, Dow Street, Dundee, DD1 5EH, UK
| | - David Horn
- Wellcome Trust Centre for Anti-Infectives Research, School of Life Sciences, University of Dundee, Dow Street, Dundee, DD1 5EH, UK.
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