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Díaz-Viraqué F, Chiribao ML, Paes-Vieira L, Machado MR, Faral-Tello P, Tomasina R, Trochine A, Robello C. New Insights into the Role of the Trypanosoma cruzi Aldo-Keto Reductase TcAKR. Pathogens 2023; 12:pathogens12010085. [PMID: 36678433 PMCID: PMC9860839 DOI: 10.3390/pathogens12010085] [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: 10/25/2022] [Revised: 12/30/2022] [Accepted: 01/01/2023] [Indexed: 01/06/2023] Open
Abstract
Chagas disease is a zoonotic infectious disease caused by the protozoan parasite Trypanosoma cruzi. It is distributed worldwide, affecting around 7 million people; there is no effective treatment, and it constitutes a leading cause of disability and premature death in the Americas. Only two drugs are currently approved for the treatment, Benznidazole and Nifurtimox, and both have to be activated by reducing the nitro-group. The T. cruzi aldo-keto reductase (TcAKR) has been related to the metabolism of benznidazole. TcAKR has been extensively studied, being most efforts focused on characterizing its implication in trypanocidal drug metabolism; however, little is known regarding its biological role. Here, we found that TcAKR is confined, throughout the entire life cycle, into the parasite mitochondria providing new insights into its biological function. In particular, in epimastigotes, TcAKR is associated with the kinetoplast, which suggests additional roles of the protein. The upregulation of TcAKR, which does not affect TcOYE expression, was correlated with an increase in PGF2α, suggesting that this enzyme is related to PGF2α synthesis in T. cruzi. Structural analysis showed that TcAKR contains a catalytic tetrad conserved in the AKR superfamily. Finally, we found that TcAKR is also involved in Nfx metabolization.
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Affiliation(s)
- Florencia Díaz-Viraqué
- Laboratorio de Interacciones Hospedero Patógeno, Unidad de Biología Molecular, Institut Pasteur de Montevideo, Montevideo 11400, Uruguay
| | - María Laura Chiribao
- Laboratorio de Interacciones Hospedero Patógeno, Unidad de Biología Molecular, Institut Pasteur de Montevideo, Montevideo 11400, Uruguay
- Departamento de Bioquímica, Facultad de Medicina Universidad de la República, Montevideo 11400, Uruguay
| | - Lisvane Paes-Vieira
- Laboratorio de Interacciones Hospedero Patógeno, Unidad de Biología Molecular, Institut Pasteur de Montevideo, Montevideo 11400, Uruguay
| | - Matias R. Machado
- Unidad de Proteínas Recombinantes, Institut Pasteur de Montevideo, Montevideo 11300, Uruguay
| | - Paula Faral-Tello
- Laboratorio de Interacciones Hospedero Patógeno, Unidad de Biología Molecular, Institut Pasteur de Montevideo, Montevideo 11400, Uruguay
| | - Ramiro Tomasina
- Laboratory of Apicomplexan Biology, Institut Pasteur de Montevideo and Departamento de Parasitología, Facultad de Medicina Universidad de la República, Montevideo 11300, Uruguay
| | - Andrea Trochine
- Centro de Referencia en Levaduras y Tecnología Cervecera (CRELTEC), Instituto Andino Patagónico de Tecnologías Biológicas y Geoambientales (IPATEC), CONICET-Universidad Nacional del Comahue, Quintral 1250, San Carlos de Bariloche 8400, Argentina
| | - Carlos Robello
- Laboratorio de Interacciones Hospedero Patógeno, Unidad de Biología Molecular, Institut Pasteur de Montevideo, Montevideo 11400, Uruguay
- Departamento de Bioquímica, Facultad de Medicina Universidad de la República, Montevideo 11400, Uruguay
- Correspondence:
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Zuma AA, Dos Santos Barrias E, de Souza W. Basic Biology of Trypanosoma cruzi. Curr Pharm Des 2021; 27:1671-1732. [PMID: 33272165 DOI: 10.2174/1381612826999201203213527] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2020] [Revised: 10/01/2020] [Accepted: 10/08/2020] [Indexed: 11/22/2022]
Abstract
The present review addresses basic aspects of the biology of the pathogenic protozoa Trypanosoma cruzi and some comparative information of Trypanosoma brucei. Like eukaryotic cells, their cellular organization is similar to that of mammalian hosts. However, these parasites present structural particularities. That is why the following topics are emphasized in this paper: developmental stages of the life cycle in the vertebrate and invertebrate hosts; the cytoskeleton of the protozoa, especially the sub-pellicular microtubules; the flagellum and its attachment to the protozoan body through specialized junctions; the kinetoplast-mitochondrion complex, including its structural organization and DNA replication; glycosome and its role in the metabolism of the cell; acidocalcisome, describing its morphology, biochemistry, and functional role; cytostome and the endocytic pathway; the organization of the endoplasmic reticulum and Golgi complex; the nucleus, describing its structural organization during interphase and division; and the process of interaction of the parasite with host cells. The unique characteristics of these structures also make them interesting chemotherapeutic targets. Therefore, further understanding of cell biology aspects contributes to the development of drugs for chemotherapy.
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Affiliation(s)
- Aline A Zuma
- Laboratorio de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho - Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Emile Dos Santos Barrias
- Laboratorio de Metrologia Aplicada a Ciencias da Vida, Diretoria de Metrologia Aplicada a Ciencias da Vida - Instituto Nacional de Metrologia, Qualidade e Tecnologia (Inmetro), Rio de Janeiro, Brazil
| | - Wanderley de Souza
- Laboratorio de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho - Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
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Santos Júnior ADCMD, Melo RM, Ferreira BVG, Pontes AH, Lima CMRD, Fontes W, Sousa MVD, Lima BDD, Ricart CAO. Quantitative proteomics and phosphoproteomics of Trypanosoma cruzi epimastigote cell cycle. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2021; 1869:140619. [PMID: 33561577 DOI: 10.1016/j.bbapap.2021.140619] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 01/19/2021] [Accepted: 02/01/2021] [Indexed: 11/30/2022]
Abstract
The protozoan Trypanosoma cruzi is the causative agent of the neglected infectious illness Chagas disease. During its life cycle it differentiates into replicative and non-replicative life stages. So far, T. cruzi cell division has been investigated by transcriptomics but not by proteomics approaches. Here we show the first quantitative proteome analysis of T. cruzi cell division. T. cruzi epimastigote cultures were subject to synchronization with hydroxyurea and harvested at different time points. Analysis by flow cytometry, bright field and fluorescence microscopy indicated that samples collected at 0 h, 2 h, 6 h and 14 h overrepresented G1, G1-S, S and M cell cycle phases, respectively. After trypsin digestion of these samples, the resulting peptides were labelled with iTRAQ and subjected to LC-MS/MS. Also, iTRAQ-labelled phosphopeptides were enriched with TiO2 to access the phosphoproteome. Overall, 597 protein groups and 94 phosphopeptides presented regulation with the most remarkable variation in abundance at 6 h (S-phase). Comparison of our proteomic data to previous transcriptome-wise analysis of epimastigote cell cycle showed 16 sequence entries in common, with the highest mRNA/protein correlation observed in transcripts with peak abundance in G1-phase. Our data revealed regulated proteins and phosphopeptides which play important roles in the control of cell division in other organisms and some of them were previously detected in the nucleus or associated with T. cruzi chromatin.
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Affiliation(s)
- Agenor de Castro Moreira Dos Santos Júnior
- Laboratory Protein Chemistry and Biochemistry, Department of Cell Biology, University of Brasília, Brasília, DF, Brazil; Laboratory of Gene Biology, Department of Cell Biology, University of Brasília, Brasília, DF, Brazil
| | - Reynaldo Magalhães Melo
- Laboratory Protein Chemistry and Biochemistry, Department of Cell Biology, University of Brasília, Brasília, DF, Brazil
| | | | - Arthur Henriques Pontes
- Laboratory Protein Chemistry and Biochemistry, Department of Cell Biology, University of Brasília, Brasília, DF, Brazil
| | | | - Wagner Fontes
- Laboratory Protein Chemistry and Biochemistry, Department of Cell Biology, University of Brasília, Brasília, DF, Brazil
| | - Marcelo Valle de Sousa
- Laboratory Protein Chemistry and Biochemistry, Department of Cell Biology, University of Brasília, Brasília, DF, Brazil
| | - Beatriz Dolabela de Lima
- Laboratory of Gene Biology, Department of Cell Biology, University of Brasília, Brasília, DF, Brazil
| | - Carlos André Ornelas Ricart
- Laboratory Protein Chemistry and Biochemistry, Department of Cell Biology, University of Brasília, Brasília, DF, Brazil.
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Pavani RS, Elias MC. Following Trypanosoma cruzi RPA-DNA Interaction Using Fluorescent In Situ Hybridization Coupled with Immunofluorescence (FISH/IF). Methods Mol Biol 2021; 2281:209-215. [PMID: 33847960 DOI: 10.1007/978-1-0716-1290-3_12] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Fluorescent in situ hybridization coupled with immunofluorescence (FISH/IF) is an assay that has been widely used to study DNA-protein interactions. The technique is based on the use of a fluorescent nucleic acid probe and fluorescent antibodies to reveal the localization of a DNA sequence and a specific protein in the cell. The interaction can be inferred by the quantification of the co-localization between the protein and the DNA. Here, we describe a detailed FISH/IF methodology that our group used to study RPA-telomere interaction in the pathogenic protozoa parasite Trypanosoma cruzi.
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Affiliation(s)
- Raphael S Pavani
- Laboratório de Ciclo Celular and Center of Toxins, Immune Response and Cell Signaling (CeTICS), Instituto Butantan, São Paulo, SP, Brazil
| | - Maria Carolina Elias
- Laboratório de Ciclo Celular and Center of Toxins, Immune Response and Cell Signaling (CeTICS), Instituto Butantan, São Paulo, SP, Brazil.
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de Lima LP, Calderano SG, da Silva MS, de Araujo CB, Vasconcelos EJR, Iwai LK, Pereira CA, Fragoso SP, Elias MC. Ortholog of the polymerase theta helicase domain modulates DNA replication in Trypanosoma cruzi. Sci Rep 2019; 9:2888. [PMID: 30814563 PMCID: PMC6393585 DOI: 10.1038/s41598-019-39348-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Accepted: 11/19/2018] [Indexed: 01/05/2023] Open
Abstract
DNA polymerase theta (Polθ), a member of the DNA polymerase family A, exhibits a polymerase C-terminal domain, a central domain, and an N-terminal helicase domain. Polθ plays important roles in DNA repair via its polymerase domain, regulating genome integrity. In addition, in mammals, Polθ modulates origin firing timing and MCM helicase recruitment to chromatin. In contrast, as a model eukaryote, Trypanosoma cruzi exhibits two individual putative orthologs of Polθ in different genomic loci; one ortholog is homologous to the Polθ C-terminal polymerase domain, and the other is homologous to the Polθ helicase domain, called Polθ-polymerase and Polθ-helicase, respectively. A pull-down assay using the T. cruzi component of the prereplication complex Orc1/Cdc6 as bait captured Polθ-helicase from the nuclear extract. Orc1/Cdc6 and Polθ-helicase directly interacted, and Polθ-helicase presented DNA unwinding and ATPase activities. A T. cruzi strain overexpressing the Polθ-helicase domain exhibited a significantly decreased amount of DNA-bound MCM7 and impaired replication origin firing. Taken together, these data suggest that Polθ-helicase modulates DNA replication by directly interacting with Orc1/Cdc6, which reduces the binding of MCM7 to DNA and thereby impairs the firing of replication origins.
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Affiliation(s)
- Loyze P de Lima
- Laboratorio Especial de Ciclo Celular, Instituto Butantan, São Paulo, Brazil
- Center of Toxins, Immune Response and Cell Signaling (CeTICS), Instituto Butantan, São Paulo, Brazil
| | | | - Marcelo S da Silva
- Laboratorio Especial de Ciclo Celular, Instituto Butantan, São Paulo, Brazil
- Center of Toxins, Immune Response and Cell Signaling (CeTICS), Instituto Butantan, São Paulo, Brazil
| | - Christiane B de Araujo
- Laboratorio Especial de Ciclo Celular, Instituto Butantan, São Paulo, Brazil
- Center of Toxins, Immune Response and Cell Signaling (CeTICS), Instituto Butantan, São Paulo, Brazil
| | - Elton J R Vasconcelos
- College of Veterinary Medicine, Western University of Health Sciences, Pomona, CA, 91766, USA
| | - Leo K Iwai
- Laboratório Especial de Toxinologia Aplicada, Instituto Butantan, São Paulo, Brazil
| | - Claudio A Pereira
- Laboratorio de Parasitología Molecular, Instituto de Investigaciones Médicas A. Lanari, Universidad de Buenos Aires - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Combatientes de Malvinas, (C1427ARO) Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
| | | | - M Carolina Elias
- Laboratorio Especial de Ciclo Celular, Instituto Butantan, São Paulo, Brazil.
- Center of Toxins, Immune Response and Cell Signaling (CeTICS), Instituto Butantan, São Paulo, Brazil.
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dos Santos Júnior ADCM, Ricart CAO, Pontes AH, Fontes W, de Souza AR, Castro MS, de Sousa MV, de Lima BD. Proteome analysis of Phytomonas serpens, a phytoparasite of medical interest. PLoS One 2018; 13:e0204818. [PMID: 30303999 PMCID: PMC6179244 DOI: 10.1371/journal.pone.0204818] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Accepted: 09/15/2018] [Indexed: 02/04/2023] Open
Abstract
The protozoan Phytomonas serpens (class Kinetoplastea) is an important phytoparasite that has gained medical importance due to its similarities to Trypanosoma cruzi, the etiological agent of Chagas disease. The present work describes the first proteome analysis of P. serpens. The parasite was separated into cytosolic and high density organelle fractions, which, together with total cell extract, were subjected to LC-MS/MS analyses. Protein identification was conducted using a comprehensive database composed of genome sequences of other related kinetoplastids. A total of 1,540 protein groups were identified among the three sample fractions. Sequences from Phytomonas sp. in the database allowed the highest number of identifications, with T. cruzi and T. brucei the human pathogens providing the greatest contribution to the identifications. Based on the proteomics data obtained, we proposed a central metabolic map of P. serpens, which includes all enzymes of the citric acid cycle. Data also revealed a new range of proteins possibly responsible for immunological cross-reactivity between P. serpens and T. cruzi.
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Affiliation(s)
- Agenor de Castro Moreira dos Santos Júnior
- Laboratory Protein Chemistry and Biochemistry, Department of Cell Biology, University of Brasília, Brasília, Federal District, Brazil
- Laboratory of Gene Biology, Department of Cell Biology, University of Brasília, Brasília, Federal District, Brazil
| | - Carlos André Ornelas Ricart
- Laboratory Protein Chemistry and Biochemistry, Department of Cell Biology, University of Brasília, Brasília, Federal District, Brazil
| | - Arthur Henriques Pontes
- Laboratory Protein Chemistry and Biochemistry, Department of Cell Biology, University of Brasília, Brasília, Federal District, Brazil
| | - Wagner Fontes
- Laboratory Protein Chemistry and Biochemistry, Department of Cell Biology, University of Brasília, Brasília, Federal District, Brazil
| | - Agnelo Rodrigues de Souza
- Laboratory Protein Chemistry and Biochemistry, Department of Cell Biology, University of Brasília, Brasília, Federal District, Brazil
- Laboratory of Gene Biology, Department of Cell Biology, University of Brasília, Brasília, Federal District, Brazil
| | - Mariana Souza Castro
- Laboratory Protein Chemistry and Biochemistry, Department of Cell Biology, University of Brasília, Brasília, Federal District, Brazil
| | - Marcelo Valle de Sousa
- Laboratory Protein Chemistry and Biochemistry, Department of Cell Biology, University of Brasília, Brasília, Federal District, Brazil
| | - Beatriz Dolabela de Lima
- Laboratory of Gene Biology, Department of Cell Biology, University of Brasília, Brasília, Federal District, Brazil
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Olmo F, Costa FC, Mann GS, Taylor MC, Kelly JM. Optimising genetic transformation of Trypanosoma cruzi using hydroxyurea-induced cell-cycle synchronisation. Mol Biochem Parasitol 2018; 226:34-36. [PMID: 29990513 PMCID: PMC6254250 DOI: 10.1016/j.molbiopara.2018.07.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 06/27/2018] [Accepted: 07/04/2018] [Indexed: 11/29/2022]
Abstract
A straightforward method for optimising Trypanosoma cruzi transfection efficiency. Facilitated by hydroxyurea-induced cell-cycle synchronization. Applicable to both episomal and integrative-mediated transformation. Reduces the time required to generate genetically modified cell lines. Increases the number of stably transformed clones.
The limited flexibility and time-consuming nature of the genetic manipulation procedures applicable to Trypanosoma cruzi continue to restrict the functional dissection of this parasite. We hypothesised that transformation efficiency could be enhanced if electroporation was timed to coincide with DNA replication. To test this, we generated epimastigote cultures enriched at the G1/S boundary using hydroxyurea-induced cell-cycle synchronisation, and then electroporated parasites at various time points after release from the cell-cycle block. We found a significant increase in transformation efficiency, with both episomal and integrative constructs, when cultures were electroporated 1 h after hydroxyurea removal. It was possible to generate genetically modified populations in less than 2 weeks, compared to the normal 4–6 weeks, with a 5 to 8-fold increase in the number of stably transformed clones. This straightforward optimisation step can be widely applied and should help streamline functional studies in T. cruzi.
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Affiliation(s)
- Francisco Olmo
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK.
| | - Fernanda C Costa
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK; Institute of Physics of São Carlos, University of São Paulo, São Carlos, 13563-120, Brazil.
| | - Gurdip Singh Mann
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK.
| | - Martin C Taylor
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK.
| | - John M Kelly
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK.
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Nuclear DNA Replication in Trypanosomatids: There Are No Easy Methods for Solving Difficult Problems. Trends Parasitol 2017; 33:858-874. [PMID: 28844718 PMCID: PMC5662062 DOI: 10.1016/j.pt.2017.08.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 07/31/2017] [Accepted: 08/02/2017] [Indexed: 01/09/2023]
Abstract
In trypanosomatids, etiological agents of devastating diseases, replication is robust and finely controlled to maintain genome stability and function in stressful environments. However, these parasites encode several replication protein components and complexes that show potentially variant composition compared with model eukaryotes. This review focuses on the advances made in recent years regarding the differences and peculiarities of the replication machinery in trypanosomatids, including how such divergence might affect DNA replication dynamics and the replication stress response. Comparing the DNA replication machinery and processes of parasites and their hosts may provide a foundation for the identification of targets that can be used in the development of chemotherapies to assist in the eradication of diseases caused by these pathogens. In trypanosomatids, DNA replication is tightly controlled by protein complexes that diverge from those of model eukaryotes. There is no consensus for the number of replication origins used by trypanosomatids; how their replication dynamics compares with that of model organisms is the subject of debate. The DNA replication rate in trypanosomatids is similar to, but slightly higher than, that of model eukaryotes, which may be related to chromatin structure and function. Recent data suggest that the origin recognition complex in trypanosomatids closely resembles the multisubunit eukaryotic model. The absence of fundamental replication-associated proteins in trypanosomatids suggests that new signaling pathways may be present in these parasites to direct DNA replication and the replicative stress response.
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Zuma AA, Santos JDO, Mendes I, de Souza W, Machado CR, Motta MCM. Chaetocin-A histone methyltransferase inhibitor-Impairs proliferation, arrests cell cycle and induces nucleolar disassembly in Trypanosoma cruzi. Acta Trop 2017; 170:149-160. [PMID: 28185826 DOI: 10.1016/j.actatropica.2017.02.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Revised: 01/12/2017] [Accepted: 02/06/2017] [Indexed: 12/15/2022]
Abstract
The Trypanosomatidae family includes pathogenic species of medical and veterinary interest. Chagas disease is endemic in Latin America, and about 8 million people are infected worldwide. There is a need for more effective drugs for the acute, undetermined and chronic phases of the disease that, in addition, do not cause side effects, stimulating the search for identification of new drug targets, as well as new chemotherapeutic targets. Trypanosomatids contain characteristic structures, such as the nucleus that undergoes a closed mitosis without chromosome formation and variations of chromatin packing in the different protozoa developmental stages. The nuclear DNA is condensed by histones that suffer post-translational modifications, such as addition of methyl groups by histone methyltransferases (MHT) and addition of acetyl groups by acetyltransferases. These processes modulate gene expression and chromatin organization, which are crucial to transcription, replication, repair and recombination. In the present study, the effects of chaetocin, a HMT inhibitor, on T. cruzi epimastigote proliferation, viability, ultrastructure and cell cycle were investigated. Results indicate that chaetocin promoted irreversible inhibition of protozoa growth, evident unpacking of nuclear heterochromatin and intense nucleolus fragmentation, which is associated with parasite cell cycle arrest and RNA transcription blockage. Taken together, data obtained with chaetocin treatment stimulate the use of histone methyltransferase inhibitors against pathogenic trypanosomatids.
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da Silva MS, Muñoz PAM, Armelin HA, Elias MC. Differences in the Detection of BrdU/EdU Incorporation Assays Alter the Calculation for G1, S, and G2 Phases of the Cell Cycle in Trypanosomatids. J Eukaryot Microbiol 2017; 64:756-770. [PMID: 28258618 DOI: 10.1111/jeu.12408] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 02/17/2017] [Accepted: 02/23/2017] [Indexed: 01/22/2023]
Abstract
Trypanosomatids are the etiologic agents of various infectious diseases in humans. They diverged early during eukaryotic evolution and have attracted attention as peculiar models for evolutionary and comparative studies. Here, we show a meticulous study comparing the incorporation and detection of the thymidine analogs BrdU and EdU in Leishmania amazonensis, Trypanosoma brucei, and Trypanosoma cruzi to monitor their DNA replication. We used BrdU- and EdU-incorporated parasites with the respective standard detection approaches: indirect immunofluorescence to detect BrdU after standard denaturation (2 M HCl) and "click" chemistry to detect EdU. We found a discrepancy between these two thymidine analogs due to the poor detection of BrdU, which is reflected on the estimative of the duration of the cell cycle phases G1, S, and G2. To solve this discrepancy, we increase the exposure of incorporated BrdU using different concentrations of HCl. Using a new value for HCl concentration, we re-estimated the phases G1, S, G2 + M, and cytokinesis durations, confirming the values found by this approach using EdU. In conclusion, we suggest that the studies using BrdU with standard detection approach, not only in trypanosomatids but also in others cell types, should be reviewed to ensure an accurate estimation of DNA replication monitoring.
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Affiliation(s)
- Marcelo Santos da Silva
- Laboratório Especial de Ciclo Celular, Center of Toxins, Immune Response and Cell Signaling (CeTICS), Butantan Institute, 1500, Vital Brasil Avenue, 05503-900, São Paulo, Brazil
| | - Paula Andrea Marin Muñoz
- Laboratório Especial de Ciclo Celular, Center of Toxins, Immune Response and Cell Signaling (CeTICS), Butantan Institute, 1500, Vital Brasil Avenue, 05503-900, São Paulo, Brazil
| | - Hugo Aguirre Armelin
- Laboratório Especial de Ciclo Celular, Center of Toxins, Immune Response and Cell Signaling (CeTICS), Butantan Institute, 1500, Vital Brasil Avenue, 05503-900, São Paulo, Brazil
| | - Maria Carolina Elias
- Laboratório Especial de Ciclo Celular, Center of Toxins, Immune Response and Cell Signaling (CeTICS), Butantan Institute, 1500, Vital Brasil Avenue, 05503-900, São Paulo, Brazil
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Picchi GFA, Zulkievicz V, Krieger MA, Zanchin NT, Goldenberg S, de Godoy LMF. Post-translational Modifications of Trypanosoma cruzi Canonical and Variant Histones. J Proteome Res 2017; 16:1167-1179. [DOI: 10.1021/acs.jproteome.6b00655] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
| | - Vanessa Zulkievicz
- Instituto Carlos Chagas, Fiocruz Parana, Curitiba, Paraná 81350-010, Brazil
| | - Marco A. Krieger
- Instituto Carlos Chagas, Fiocruz Parana, Curitiba, Paraná 81350-010, Brazil
| | - Nilson T. Zanchin
- Instituto Carlos Chagas, Fiocruz Parana, Curitiba, Paraná 81350-010, Brazil
| | - Samuel Goldenberg
- Instituto Carlos Chagas, Fiocruz Parana, Curitiba, Paraná 81350-010, Brazil
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12
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Pavani RS, da Silva MS, Fernandes CAH, Morini FS, Araujo CB, Fontes MRDM, Sant’Anna OA, Machado CR, Cano MI, Fragoso SP, Elias MC. Replication Protein A Presents Canonical Functions and Is Also Involved in the Differentiation Capacity of Trypanosoma cruzi. PLoS Negl Trop Dis 2016; 10:e0005181. [PMID: 27984589 PMCID: PMC5161316 DOI: 10.1371/journal.pntd.0005181] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Accepted: 11/10/2016] [Indexed: 02/03/2023] Open
Abstract
Replication Protein A (RPA), the major single stranded DNA binding protein in eukaryotes, is composed of three subunits and is a fundamental player in DNA metabolism, participating in replication, transcription, repair, and the DNA damage response. In human pathogenic trypanosomatids, only limited studies have been performed on RPA-1 from Leishmania. Here, we performed in silico, in vitro and in vivo analysis of Trypanosoma cruzi RPA-1 and RPA-2 subunits. Although computational analysis suggests similarities in DNA binding and Ob-fold structures of RPA from T. cruzi compared with mammalian and fungi RPA, the predicted tridimensional structures of T. cruzi RPA-1 and RPA-2 indicated that these molecules present a more flexible tertiary structure, suggesting that T. cruzi RPA could be involved in additional responses. Here, we demonstrate experimentally that the T. cruzi RPA complex interacts with DNA via RPA-1 and is directly related to canonical functions, such as DNA replication and DNA damage response. Accordingly, a reduction of TcRPA-2 expression by generating heterozygous knockout cells impaired cell growth, slowing down S-phase progression. Moreover, heterozygous knockout cells presented a better efficiency in differentiation from epimastigote to metacyclic trypomastigote forms and metacyclic trypomastigote infection. Taken together, these findings indicate the involvement of TcRPA in the metacyclogenesis process and suggest that a delay in cell cycle progression could be linked with differentiation in T. cruzi.
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Affiliation(s)
- Raphael Souza Pavani
- Laboratório Especial de Ciclo Celular, Instituto Butantan, São Paulo, São Paulo, Brazil
- Center of Toxins, Immune Response and Cell Signaling—CeTICS, Instituto Butantan, São Paulo, São Paulo, Brazil
| | - Marcelo Santos da Silva
- Laboratório Especial de Ciclo Celular, Instituto Butantan, São Paulo, São Paulo, Brazil
- Center of Toxins, Immune Response and Cell Signaling—CeTICS, Instituto Butantan, São Paulo, São Paulo, Brazil
| | - Carlos Alexandre Henrique Fernandes
- Departamento de Física e Biofísica, Instituto de Biociências, Universidade Estadual Paulista Júlio de Mesquita Filho -UNESP, Botucatu, São Paulo, Brazil
| | | | - Christiane Bezerra Araujo
- Laboratório Especial de Ciclo Celular, Instituto Butantan, São Paulo, São Paulo, Brazil
- Center of Toxins, Immune Response and Cell Signaling—CeTICS, Instituto Butantan, São Paulo, São Paulo, Brazil
| | - Marcos Roberto de Mattos Fontes
- Departamento de Física e Biofísica, Instituto de Biociências, Universidade Estadual Paulista Júlio de Mesquita Filho -UNESP, Botucatu, São Paulo, Brazil
| | - Osvaldo Augusto Sant’Anna
- Center of Toxins, Immune Response and Cell Signaling—CeTICS, Instituto Butantan, São Paulo, São Paulo, Brazil
- Laboratório de Imunoquímica, Instituto Butantan, São Paulo, São Paulo, Brazil
| | - Carlos Renato Machado
- Departamento de Bioquímica e Imunologia, ICB, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Maria Isabel Cano
- Departamento de Genética, Instituto de Biociências, Universidade Estadual Paulista Julio Mesquita Filho—UNESP, Botucatu, São Paulo, Brazil
| | | | - Maria Carolina Elias
- Laboratório Especial de Ciclo Celular, Instituto Butantan, São Paulo, São Paulo, Brazil
- Center of Toxins, Immune Response and Cell Signaling—CeTICS, Instituto Butantan, São Paulo, São Paulo, Brazil
- * E-mail:
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Abstract
Replication of Trypanosoma cruzi, the etiological agent of Chagas disease, displays peculiar features, such as absence of chromosome condensation and closed mitosis. Although previous proteome and subproteome analyses of T. cruzi have been carried out, the nuclear subproteome of this protozoan has not been described. Here, we report, for the first time to the best of our knowledge, the isolation and proteome analysis of T. cruzi nuclear fraction. For that, T. cruzi epimastigote cells were lysed and subjected to cell fractionation using two steps of sucrose density gradient centrifugation. The purity of the nuclear fraction was confirmed by phase contrast and fluorescence microscopy. Liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) allowed the identification of 864 proteins. Among those, 272 proteins were annotated as putative uncharacterized, and 275 had not been previously reported on global T. cruzi proteome analysis. Additionally, to support our enrichment method, bioinformatics analysis in DAVID was carried out. It grouped the nuclear proteins in 65 gene clusters, wherein the clusters with the highest enrichment scores harbor members with chromatin organization and DNA binding functions.
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Zuma AA, Cavalcanti DP, Zogovich M, Machado ACL, Mendes IC, Thiry M, Galina A, de Souza W, Machado CR, Motta MCM. Unveiling the effects of berenil, a DNA-binding drug, on Trypanosoma cruzi: implications for kDNA ultrastructure and replication. Parasitol Res 2014; 114:419-30. [DOI: 10.1007/s00436-014-4199-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Accepted: 10/17/2014] [Indexed: 11/29/2022]
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Lacombe OK, Zuma AA, da Silva CC, de Souza W, Motta MCM. Effects of camptothecin derivatives and topoisomerase dual inhibitors on Trypanosoma cruzi growth and ultrastructure. J Negat Results Biomed 2014; 13:11. [PMID: 24917086 PMCID: PMC4066697 DOI: 10.1186/1477-5751-13-11] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2014] [Accepted: 05/22/2014] [Indexed: 12/02/2022] Open
Abstract
Background Trypanosoma cruzi is the etiological agent of Chagas’ disease that is an endemic disease in Latin America and affects about 8 million people. This parasite belongs to the Trypanosomatidae family which contains a single mitochondrion with an enlarged region, named kinetoplast that harbors the mitochondrial DNA (kDNA). The kinetoplast and the nucleus present a great variety of essential enzymes involved in DNA replication and topology, including DNA topoisomerases. Such enzymes are considered to be promising molecular targets for cancer treatment and for antiparasitic chemotherapy. In this work, the proliferation and ultrastructure of T. cruzi epimastigotes were evaluated after treatment with eukaryotic topoisomerase I inhibitors, such as topotecan and irinotecan, as well as with dual inhibitors (compounds that block eukaryotic topoisomerase I and topoisomerase II activities), such as baicalein, luteolin and evodiamine. Previous studies have shown that such inhibitors were able to block the growth of tumor cells, however most of them have never been tested on trypanosomatids. Results Considering the effects of topoisomerase I inhibitors, our results showed that topotecan decreased cell proliferation and caused unpacking of nuclear heterochromatin, however none of these alterations were observed after treatment with irinotecan. The dual inhibitors baicalein and evodiamine decreased cell growth; however the nuclear and kinetoplast ultrastructures were not affected. Conclusions Taken together, our data showed that camptothecin is more efficient than its derivatives in decreasing T. cruzi proliferation. Furthermore, we conclude that drugs pertaining to a certain class of topoisomerase inhibitors may present different efficiencies as chemotherapeutical agents.
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Affiliation(s)
| | | | | | | | - Maria Cristina M Motta
- Laboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, 21491-590 Rio de Janeiro, RJ, Brazil.
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Zuma AA, Mendes IC, Reignault LC, Elias MC, de Souza W, Machado CR, Motta MCM. How Trypanosoma cruzi handles cell cycle arrest promoted by camptothecin, a topoisomerase I inhibitor. Mol Biochem Parasitol 2014; 193:93-100. [DOI: 10.1016/j.molbiopara.2014.02.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Revised: 01/21/2014] [Accepted: 02/03/2014] [Indexed: 10/25/2022]
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Kaufmann D, Gassen A, Maiser A, Leonhardt H, Janzen CJ. Regulation and spatial organization of PCNA in Trypanosoma brucei. Biochem Biophys Res Commun 2012; 419:698-702. [PMID: 22387477 DOI: 10.1016/j.bbrc.2012.02.082] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2012] [Accepted: 02/14/2012] [Indexed: 11/15/2022]
Abstract
As in most eukaryotic cells, replication is regulated by a conserved group of proteins in the early-diverged parasite Trypanosoma brucei. Only a few components of the replication machinery have been described in this parasite and regulation, sub-nuclear localization and timing of replication are not well understood. We characterized the proliferating cell nuclear antigen in T. brucei (TbPCNA) to establish a spatial and temporal marker for replication. Interestingly, PCNA distribution and regulation is different compared to the closely related parasites Trypanosoma cruzi and Leishmania donovani. TbPCNA foci are clearly detectable during S phase of the cell cycle but in contrast to T. cruzi they are not preferentially located at the nuclear periphery. Furthermore, PCNA seems to be degraded when cells enter G2 phase in T. brucei suggesting different modes of replication regulation or functions of PCNA in these closely related eukaryotes.
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Affiliation(s)
- Doris Kaufmann
- University of Munich (LMU), Department Biology I, Genetics, Großhaderner Str. 2-4, 82152 Martinsried, Germany
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Calderano SG, de Melo Godoy PD, Motta MCM, Mortara RA, Schenkman S, Elias MC. Trypanosoma cruzi DNA replication includes the sequential recruitment of pre-replication and replication machineries close to nuclear periphery. Nucleus 2012; 2:136-45. [PMID: 21738836 DOI: 10.4161/nucl.2.2.15134] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2010] [Revised: 02/03/2011] [Accepted: 02/11/2011] [Indexed: 11/19/2022] Open
Abstract
In eukaryotes, many nuclear processes are spatially compartmentalized. Previously, we have shown that in Trypanosoma cruzi, an early-divergent eukaryote, DNA replication occurs at the nuclear periphery where chromosomes remain constrained during the S phase of the cell cycle. We followed Orc1/Cdc6, a pre-replication machinery component and the proliferating cell nuclear antigen (PCNA), a component of replication machinery, during the cell cycle of this protozoon. We found that, at the G(1) stage, TcOrc1/Cdc6 and TcPCNA are dispersed throughout the nuclear space. During the G(1)/S transition, TcOrc1/Cdc6 migrates to a region close to nuclear periphery. At the onset of S phase, TcPCNA is loaded onto the DNA and remains constrained close to nuclear periphery. Finally, in G(2), mitosis and cytokinesis, TcOrc1/Cdc6 and TcPCNA are dispersed throughout the nuclear space. Based on these findings, we propose that DNA replication in T. cruzi is accomplished by the organization of functional machineries in a spatial-temporal manner.
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Affiliation(s)
- Simone Guedes Calderano
- Laboratório de Parasitologia, Instituto Butantan, Universidade Federal de São Paulo, São Paulo, Brazil
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Schenkman S, Pascoalino BDS, Nardelli SC. Nuclear structure of Trypanosoma cruzi. ADVANCES IN PARASITOLOGY 2011; 75:251-83. [PMID: 21820560 DOI: 10.1016/b978-0-12-385863-4.00012-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The presence of nucleus in living organisms characterizes the Eukaryote domain. The nucleus compartmentalizes the genetic material surrounded by a double membrane called nuclear envelope. The nucleus has been observed since the advent of the light microscope, and sub-compartments such as nucleoli, diverse nuclear bodies and condensed chromosomes have been later recognized, being part of highly organized and dynamic structure. The significance and function of such organization has increased with the understanding of transcription, replication, DNA repair, recombination processes. It is now recognized as consequence of adding complexity and regulation in more complex eukaryotic cells. Here we provide a description of the actual stage of knowledge of the nuclear structure of Trypanosoma cruzi. As an early divergent eukaryote, it presents unique and/or reduced events of DNA replication, transcription and repair as well as RNA processing and transport to the cytosol. Nevertheless, it shows peculiar structure changes accordingly to the cell cycle and stage of differentiation. T. cruzi proliferates only as epimastigote and amastigote stages, and when these forms differentiate in trypomastigote forms, their cell cycle is arrested. This arrested stage is capable of invading mammalian cells and of surviving harsh conditions, such as the gut of the insect vector and mammalian macrophages. Transcription and replication decrease during transformation in trypomastigotes implicating large alterations in the nuclear structure. Recent evidences also suggest that T. cruzi nucleus respond to oxidative and nutritional stresses. Due to the phylogenetic proximity with other well-known trypanosomes, such as Trypanosoma brucei and Leishmania major, they are expected to have similar nuclear organization, although differences are noticed due to distinct life cycles, cellular organizations and the specific adaptations for surviving in different host environments. Therefore, the general features of T. cruzi nuclear structure regarding unique characteristics of this protozoan parasite will be described.
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Affiliation(s)
- Sergio Schenkman
- Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo, São Paulo, Brazil
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Souza RT, Lima FM, Barros RM, Cortez DR, Santos MF, Cordero EM, Ruiz JC, Goldenberg S, Teixeira MMG, da Silveira JF. Genome size, karyotype polymorphism and chromosomal evolution in Trypanosoma cruzi. PLoS One 2011; 6:e23042. [PMID: 21857989 PMCID: PMC3155523 DOI: 10.1371/journal.pone.0023042] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2011] [Accepted: 07/04/2011] [Indexed: 01/07/2023] Open
Abstract
Background The Trypanosoma cruzi genome was sequenced from a hybrid strain (CL Brener). However, high allelic variation and the repetitive nature of the genome have prevented the complete linear sequence of chromosomes being determined. Determining the full complement of chromosomes and establishing syntenic groups will be important in defining the structure of T. cruzi chromosomes. A large amount of information is now available for T. cruzi and Trypanosoma brucei, providing the opportunity to compare and describe the overall patterns of chromosomal evolution in these parasites. Methodology/Principal Findings The genome sizes, repetitive DNA contents, and the numbers and sizes of chromosomes of nine strains of T. cruzi from four lineages (TcI, TcII, TcV and TcVI) were determined. The genome of the TcI group was statistically smaller than other lineages, with the exception of the TcI isolate Tc1161 (José-IMT). Satellite DNA content was correlated with genome size for all isolates, but this was not accompanied by simultaneous amplification of retrotransposons. Regardless of chromosomal polymorphism, large syntenic groups are conserved among T. cruzi lineages. Duplicated chromosome-sized regions were identified and could be retained as paralogous loci, increasing the dosage of several genes. By comparing T. cruzi and T. brucei chromosomes, homologous chromosomal regions in T. brucei were identified. Chromosomes Tb9 and Tb11 of T. brucei share regions of syntenic homology with three and six T. cruzi chromosomal bands, respectively. Conclusions Despite genome size variation and karyotype polymorphism, T. cruzi lineages exhibit conservation of chromosome structure. Several syntenic groups are conserved among all isolates analyzed in this study. The syntenic regions are larger than expected if rearrangements occur randomly, suggesting that they are conserved owing to positive selection. Mapping of the syntenic regions on T. cruzi chromosomal bands provides evidence for the occurrence of fusion and split events involving T. brucei and T. cruzi chromosomes.
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Affiliation(s)
- Renata T. Souza
- Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Fábio M. Lima
- Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Roberto Moraes Barros
- Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Danielle R. Cortez
- Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Michele F. Santos
- Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Esteban M. Cordero
- Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | | | | | - Marta M. G. Teixeira
- Departamento de Parasitologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
| | - José Franco da Silveira
- Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
- * E-mail:
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Abstract
Trypanosomes are a group of protozoan eukaryotes, many of which are major parasites of humans and livestock. The genomes of trypanosomes and their modes of gene expression differ in several important aspects from those of other eukaryotic model organisms. Protein-coding genes are organized in large directional gene clusters on a genome-wide scale, and their polycistronic transcription is not generally regulated at initiation. Transcripts from these polycistrons are processed by global trans-splicing of pre-mRNA. Furthermore, in African trypanosomes, some protein-coding genes are transcribed by a multifunctional RNA polymerase I from a specialized extranucleolar compartment. The primary DNA sequence of the trypanosome genomes and their cellular organization have usually been treated as separate entities. However, it is becoming increasingly clear that in order to understand how a genome functions in a living cell, we will need to unravel how the one-dimensional genomic sequence and its trans-acting factors are arranged in the three-dimensional space of the eukaryotic nucleus. Understanding this cell biology of the genome will be crucial if we are to elucidate the genetic control mechanisms of parasitism. Here, we integrate the concepts of nuclear architecture, deduced largely from studies of yeast and mammalian nuclei, with recent developments in our knowledge of the trypanosome genome, gene expression, and nuclear organization. We also compare this nuclear organization to those in other systems in order to shed light on the evolution of nuclear architecture in eukaryotes.
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Abstract
RNA interference (RNAi) is defined as the mechanism through which double-stranded RNA (dsRNA) triggers degradation of homologous transcripts. Besides providing an invaluable tool to downregulate gene expression in a variety of organisms, it is now evident that RNAi acts beyond the cytoplasm and is involved in a variety of gene-silencing phenomena in the nucleus. In the present work we review the current status of the knowledge about RNAi in protozoan parasites that belong to the Trypanosoma genus and have medical relevance. While RNAi was first discovered in Trypanosoma brucei, it became evident that other members of the same genus of organisms, namely Trypanosoma cruzi, does not possess RNAi, probably due to the lack of Ago protein analogs in their genomes. We will discuss the genome organization of Trypanosoma cruzi and propose that the absence of both RNAi and gene promoters is symptomatic of alternative epigenetic controls in this parasite orchestrated by parasite-host interactions. Whereas in Trypanosoma brucei, RNAi and other epigenetic controls dictate alternative transcriptional programs critical for virulence.
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Elias MC, Nardelli SC, Schenkman S. Chromatin and nuclear organization in Trypanosoma cruzi. Future Microbiol 2009; 4:1065-74. [DOI: 10.2217/fmb.09.74] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
A total of 100 years have passed since the discovery of the protozoan Trypanosoma cruzi, the etiologic agent of Chagas’ disease. Since its discovery, the molecular and cellular biology of this early divergent eukaryote, as well as its interactions with the mammalian and insect hosts, has progressed substantially. It is now clear that this parasite presents unique mechanisms controlling gene expression, DNA replication, cell cycle and differentiation, generating several morphological forms that are adapted to survive in different hosts. In recent years, the relationship between the chromatin structure and nuclear organization with the unusual transcription, splicing, DNA replication and DNA repair mechanisms have been investigated in T. cruzi. This article reviews the relevant aspects of these mechanisms in relation to chromatin and nuclear organization.
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Affiliation(s)
| | - Sheila Cristina Nardelli
- Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo, R. Botucatu 862 8a, 04023-062 São Paulo, Brazil
| | - Sergio Schenkman
- Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo, R. Botucatu 862 8a, 04023-062 São Paulo, Brazil
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Trypanosome prereplication machinery contains a single functional orc1/cdc6 protein, which is typical of archaea. EUKARYOTIC CELL 2009; 8:1592-603. [PMID: 19717742 DOI: 10.1128/ec.00161-09] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
In unicellular eukaryotes, such as Saccharomyces cerevisiae, and in multicellular organisms, the replication origin is recognized by the heterohexamer origin recognition complex (ORC) containing six proteins, Orc1 to Orc6, while in members of the domain Archaea, the replication origin is recognized by just one protein, Orc1/Cdc6; the sequence of Orc1/Cdc6 is highly related to those of Orc1 and Cdc6. Similar to Archaea, trypanosomatid genomes contain only one gene encoding a protein named Orc1. Since trypanosome Orc1 is also homologous to Cdc6, in this study we named the Orc1 protein from trypanosomes Orc1/Cdc6. Here we show that the recombinant Orc1/Cdc6 from Trypanosoma cruzi (TcOrc1/Cdc6) and from Trypanosoma brucei (TbOrc1/Cdc6) present ATPase activity, typical of prereplication machinery components. Also, TcOrc1/Cdc6 and TbOrc1/Cdc6 replaced yeast Cdc6 but not Orc1 in a phenotypic complementation assay. The induction of Orc1/Cdc6 silencing by RNA interference in T. brucei resulted in enucleated cells, strongly suggesting the involvement of Orc1/Cdc6 in DNA replication. Orc1/Cdc6 is expressed during the entire cell cycle in the nuclei of trypanosomes, remaining associated with chromatin in all stages of the cell cycle. These results allowed us to conclude that Orc1/Cdc6 is indeed a member of the trypanosome prereplication machinery and point out that trypanosomes carry a prereplication machinery that is less complex than other eukaryotes and closer to archaea.
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Distinct acetylation of Trypanosoma cruzi histone H4 during cell cycle, parasite differentiation, and after DNA damage. Chromosoma 2009; 118:487-99. [PMID: 19396454 DOI: 10.1007/s00412-009-0213-9] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2008] [Revised: 04/04/2009] [Accepted: 04/06/2009] [Indexed: 10/20/2022]
Abstract
Histones of trypanosomes are quite divergent when compared to histones of most eukaryotes. Nevertheless, the histone H4 of Trypanosoma cruzi, the protozoan that causes Chagas' disease, is acetylated in the N terminus at lysines 4, 10, and 14. Here, we investigated the cellular distribution of histone H4 containing each one of these posttranslational modifications by using specific antibodies. Histone H4 acetylated at lysine 4 (H4-K4ac) is found in the entire nuclear space preferentially at dense chromatin regions, excluding the nucleolus of replicating epimastigote forms of the parasite. In contrast, histone H4 acetylated either at K10 or K14 is found at dispersed foci all over the nuclei and at the interface between dense and nondense chromatin areas as observed by ultrastructural immunocytochemistry. The level of acetylation at K4 decreases in nonreplicating forms of the parasites when compared to K10 and K14 acetylations. Antibodies recognizing the K14 acetylation strongly labeled cells at G2 and M stages of the cell cycle. Besides that, hydroxyurea synchronized parasites show an increased acetylation at K4, K10, and K14 after S phase. Moreover, we do not observed specific colocalization of K4 modifications with the major sites of RNA polymerase II. Upon gamma-irradiation that stops parasite replication until the DNA is repaired, dense chromatin disappears and K4 acetylation decreases, while K10 and K14 acetylation increase. These results indicate that each lysine acetylation has a different role in T. cruzi. While K4 acetylation occurs preferentially in proliferating situations and accumulates in packed chromatin, K10 and K14 acetylations have a particular distribution probably at the boundaries between packed and unpacked chromatin.
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Duhagon MA, Pastro L, Sotelo-Silveira JR, Pérez-Díaz L, Maugeri D, Nardelli SC, Schenkman S, Williams N, Dallagiovanna B, Garat B. The Trypanosoma cruzi nucleic acid binding protein Tc38 presents changes in the intramitochondrial distribution during the cell cycle. BMC Microbiol 2009; 9:34. [PMID: 19210781 PMCID: PMC2654453 DOI: 10.1186/1471-2180-9-34] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2008] [Accepted: 02/11/2009] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Tc38 of Trypanosoma cruzi has been isolated as a single stranded DNA binding protein with high specificity for the poly [dT-dG] sequence. It is present only in Kinetoplastidae protozoa and its sequence lacks homology to known functional domains. Tc38 orthologues present in Trypanosoma brucei and Leishmania were proposed to participate in quite different cellular processes. To further understand the function of this protein in Trypanosoma cruzi, we examined its in vitro binding to biologically relevant [dT-dG] enriched sequences, its expression and subcellular localization during the cell cycle and through the parasite life stages. RESULTS By using specific antibodies, we found that Tc38 protein from epimastigote extracts participates in complexes with the poly [dT-dG] probe as well as with the universal minicircle sequence (UMS), a related repeated sequence found in maxicircle DNA, and the telomeric repeat. However, we found that Tc38 predominantly localizes into the mitochondrion. Though Tc38 is constitutively expressed through non-replicating and replicating life stages of T. cruzi, its subcellular localization in the unique parasite mitochondrion changes according to the cell cycle stage. In epimastigotes, Tc38 is found only in association with kDNA in G1 phase. From the S to G2 phase the protein localizes in two defined and connected spots flanking the kDNA. These spots disappear in late G2 turning into a diffuse dotted signal which extends beyond the kinetoplast. This later pattern is more evident in mitosis and cytokinesis. Finally, late in cytokinesis Tc38 reacquires its association with the kinetoplast. In non-replicating parasite stages such as trypomastigotes, the protein is found only surrounding the entire kinetoplast structure. CONCLUSIONS The dynamics of Tc38 subcellular localization observed during the cell cycle and life stages support a major role for Tc38 related to kDNA replication and maintenance.
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Affiliation(s)
- María A Duhagon
- Laboratorio de Interacciones Moleculares, Facultad de Ciencias, Montevideo, Uruguay.
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Histone H1 of Trypanosoma cruzi is concentrated in the nucleolus region and disperses upon phosphorylation during progression to mitosis. EUKARYOTIC CELL 2008; 7:560-8. [PMID: 18281601 DOI: 10.1128/ec.00460-07] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Phosphorylation of histone H1 is intimately related to the cell cycle progression in higher eukaryotes, reaching maximum levels during mitosis. We have previously shown that in the flagellated protozoan Trypanosoma cruzi, which does not condense chromatin during mitosis, histone H1 is phosphorylated at a single cyclin-dependent kinase site. By using an antibody that recognizes specifically the phosphorylated T. cruzi histone H1 site, we have now confirmed that T. cruzi histone H1 is also phosphorylated in a cell cycle-dependent manner. Differently from core histones, the bulk of nonphosphorylated histone H1 in G(1) and S phases of the cell cycle is concentrated in the central regions of the nucleus, which contains the nucleolus and less densely packed chromatin. When cells pass G(2), histone H1 becomes phosphorylated and starts to diffuse. At the onset of mitosis, histone H1 phosphorylation is maximal and found in the entire nuclear space. As permeabilized parasites preferentially lose phosphorylated histone H1, we conclude that this modification promotes its release from less condensed and nucleolar chromatin after G(2).
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Galindo M, Sabaj V, Espinoza I, Toro GC, Búa J, Grenet J, López-Solís R, Ruiz AM, Galanti N. Chromosomal size conservation through the cell cycle supports karyotype stability inTrypanosoma cruzi. FEBS Lett 2007; 581:2022-6. [PMID: 17467699 DOI: 10.1016/j.febslet.2007.03.093] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2007] [Accepted: 03/24/2007] [Indexed: 11/16/2022]
Abstract
The Trypanosoma cruzi karyotype shows an extensive chromosomal size polymorphism. Absence of condensed mitotic chromosomes and chromatin fragility are characteristic features of T. cruzi which would allow DNA breaks and chromosomal rearrangements during cell proliferation. We have investigated by pulsed field gel electrophoresis (PFGE) eventual changes in chromosomal size during exponential and stationary phases of T. cruzi epimastigotes in culture, in G0 trypomastigotes and throughout the cell cycle in synchronized epimastigotes. T. cruzi molecular karyotype was stable throughout the cell cycle and during differentiation. Thus, the chromosomal size polymorphism previously reported in T. cruzi contrasts with the stability of the molecular karyotype observed here and suggests that chromosomal rearrangements leading to changes in chromosomal size are scarce events during the clonal propagation of this parasite.
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Affiliation(s)
- Mario Galindo
- Program of Cellular and Molecular Biology, Institute of Biomedical Sciences (ICBM), Faculty of Medicine, University of Chile, Santiago, Chile.
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Rani SA, Pitts B, Beyenal H, Veluchamy RA, Lewandowski Z, Davison WM, Buckingham-Meyer K, Stewart PS. Spatial patterns of DNA replication, protein synthesis, and oxygen concentration within bacterial biofilms reveal diverse physiological states. J Bacteriol 2007; 189:4223-33. [PMID: 17337582 PMCID: PMC1913414 DOI: 10.1128/jb.00107-07] [Citation(s) in RCA: 213] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
It has long been suspected that microbial biofilms harbor cells in a variety of activity states, but there have been few direct experimental visualizations of this physiological heterogeneity. Spatial patterns of DNA replication and protein synthetic activity were imaged and quantified in staphylococcal biofilms using immunofluorescent detection of pulse-labeled DNA and also an inducible green fluorescent protein (GFP) construct. Stratified patterns of DNA synthetic and protein synthetic activity were observed in all three biofilm systems to which the techniques were applied. In a colony biofilm system, the dimensions of the zone of anabolism at the air interface ranged from 16 to 38 microm and corresponded with the depth of oxygen penetration measured with a microelectrode. A second zone of activity was observed along the nutrient interface of the biofilm. Much of the biofilm was anabolically inactive. Since dead cells constituted only 10% of the biofilm population, most of the inactive cells in the biofilm were still viable. Collectively, these results suggest that staphylococcal biofilms contain cells in at least four distinct states: growing aerobically, growing fermentatively, dead, and dormant. The variety of activity states represented in a biofilm may contribute to the special ecology and tolerance to antimicrobial agents of biofilms.
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Affiliation(s)
- Suriani Abdul Rani
- Center for Biofilm Engineering, Montana State University-Bozeman, Bozeman, MT 59717-3980, USA
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Dossin FDM, Schenkman S. Actively transcribing RNA polymerase II concentrates on spliced leader genes in the nucleus of Trypanosoma cruzi. EUKARYOTIC CELL 2005; 4:960-70. [PMID: 15879530 PMCID: PMC1140094 DOI: 10.1128/ec.4.5.960-970.2005] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
RNA polymerase II of trypanosomes, early diverging eukaryotes, transcribes long polycistronic messages, which are not capped but are processed by trans-splicing and polyadenylation to form mature mRNAs. The same RNA polymerase II also transcribes the genes coding for the spliced leader RNA, which are capped, exported to the cytoplasm, processed, and reimported into the nucleus before they are used as splicing donors to form mRNAs from pre-mRNA polycistronic transcripts. As pre-mRNA and spliced leader transcription events appear to be uncoupled, we studied how the RNA polymerase II is distributed in the nucleus of Trypanosoma cruzi. Using specific antibodies to the T. cruzi RNA polymerase II unique carboxy-terminal domain, we demonstrated that large amounts of the enzyme are found concentrated in a domain close to the parasite nucleolus and containing the spliced leader genes. The remaining RNA polymerase II is diffusely distributed in the nucleoplasm. The spliced leader-associated RNA polymerase II localization is dependent on the cell transcriptional state. It disperses when transcription is blocked by alpha-amanitin and actinomycin D. Tubulin genes are excluded from this domain, suggesting that it may exclusively be the transcriptional site of spliced leader genes. Trypomastigote forms of the parasite, which have reduced spliced leader transcription, show less RNA polymerase II labeling, and the spliced leader genes are more dispersed in the nucleoplasm. These results provide strong evidences that transcription of spliced leader RNAs occurs in a particular domain in the T. cruzi nucleus.
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Affiliation(s)
- Fernando de Macedo Dossin
- Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo, R. Botucatu 862 8 andar, 04023-062 São Paulo, Brazil.
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da Cunha JPC, Nakayasu ES, Elias MC, Pimenta DC, Téllez-Iñón MT, Rojas F, Muñoz MJ, Manuel M, Almeida IC, Schenkman S. Trypanosoma cruzi histone H1 is phosphorylated in a typical cyclin dependent kinase site accordingly to the cell cycle. Mol Biochem Parasitol 2005; 140:75-86. [PMID: 15694489 DOI: 10.1016/j.molbiopara.2004.12.007] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2004] [Revised: 12/20/2004] [Accepted: 12/21/2004] [Indexed: 10/25/2022]
Abstract
Histone H1 of most eukaryotes is phosphorylated during the cell cycle progression and seems to play a role in the regulation of chromatin structure, affecting replication and chromosome condensation. In trypanosomatids, histone H1 lacks the globular domain and is shorter when compared with the histone of other eukaryotes. We have previously shown that in Trypanosoma cruzi, the agent of Chagas' disease, histone H1 is phosphorylated and this increases its dissociation from chromatin. Here, we demonstrate using mass spectrometry analysis that T. cruzi histone H1 is only phosphorylated at the serine 12 in the sequence SPKK, a typical cyclin-dependent kinase site. We also found a correlation between the phosphorylation state of histone H1 and the cell cycle. Hydroxyurea and lactacystin, which, respectively, arrest parasites at the G1/S and G2/M stages of the cell cycle, increased the level of histone H1 phosphorylation. Cyclin-dependent kinase-related enzymes TzCRK3, and less intensely the TzCRK1 were able to phosphorylate histone H1 in vitro. Histone H1 dephosphorylation was prevented by treating the parasites with okadaic acid but not with calyculin A. These findings suggest that T. cruzi histone H1 phosphorylation is promoted by cyclin dependent kinases, present during S through G2 phase of the cell cycle, and its dephosphorylation is promoted by specific phosphatases.
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Affiliation(s)
- Julia Pinheiro Chagas da Cunha
- Departamento de Microbiologia, Imunologia e Parasitologia, R. Botucatu 862-8(a), EPM-UNIFESP, São Paulo, SP 04023-062, Brazil
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Elias MCQB, Vargas NS, Zingales B, Schenkman S. Organization of satellite DNA in the genome of Trypanosoma cruzi. Mol Biochem Parasitol 2003; 129:1-9. [PMID: 12798501 DOI: 10.1016/s0166-6851(03)00054-9] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Trypanosoma cruzi has about 10(5) copies of a 195 bp repeat, called satellite DNA, which correspond to about 10% of the total DNA. Since very little is known about satellite distribution and function in this and in many other organisms, we studied the genomic organization of satellite DNA in T. cruzi Y, CL Brener, and Silvio X10 cl1 strains. We found that satellite repeats are present in some, but not all, chromosomes in these strains. We also found that the copy number of the satellite repeats is distinct in each one of the strains. We have estimated that the satellite DNA is four to six times more abundant in Y and CL Brener strains as compared to Silvio X10 cl1. Despite these differences, the repeated units are organized in a similar way. Based on restriction nuclease digestion analysis, we found that satellite repeats are grouped in clusters comprising about 30+/-10 kb. The same cluster size was also found in the different chromosomes, as seen by two-dimensional pulsed field-gel electrophoresis. As evidenced by a fluorescence hybridization assay of spread DNA fibers, we additionally found that these clusters are constrained in specific regions of the chromosomes. Sequence analysis of several repeat units of satellite DNA of the three strains revealed a remarkable similarity with conserved nucleotide blocks separated by more variable regions. Such conserved distribution and common sequence may suggest that these repeated units might have a structural role in the T. cruzi chromosomes.
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Affiliation(s)
- M Carolina Q B Elias
- Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo, São Paulo SP, Brazil
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