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Durrani H, Bjork JA, Zimmer SL. Role of PIP39 in oxidative stress response appears conserved in kinetoplastids. Mol Biochem Parasitol 2024; 259:111620. [PMID: 38653348 DOI: 10.1016/j.molbiopara.2024.111620] [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: 03/14/2024] [Revised: 04/04/2024] [Accepted: 04/18/2024] [Indexed: 04/25/2024]
Abstract
Kinetoplastids, a group of flagellated protists that are often insect intestinal parasites, encounter various sources of oxidative stress. Such stressors include reactive oxygen species, both internally produced within the protist, and induced externally by host immune responses. This investigation focuses on the role of a highly conserved aspartate-based protein phosphatase, PTP-Interacting protein (PIP39) in managing oxidative stress. In addition to its well accepted role in a Trypanosoma brucei life stage transition, there is evidence of PIP39 participation in the T. brucei oxidative stress response. To examine whether this latter PIP39 role may exist more broadly, we aimed to elucidate PIP39's contribution to redox homeostasis in the monoxenous parasite Leptomonas seymouri. Utilizing CRISPR-Cas9-mediated elimination of PIP39 in conjunction with oxidative stress assays, we demonstrate that PIP39 is required for cellular tolerance to oxidative stress in L. seymouri, positing it as a putative regulatory node for adaptive stress responses. We propose that future analysis of L. seymouri PIP39 enzymatic activity, regulation, and potential localization to a specialized organelle termed a glycosome will contribute to a deeper understanding of the molecular mechanisms by which protozoan parasites adapt to oxidative environments. Our study also demonstrates success at using gene editing tools developed for Leishmania for the related L. seymouri.
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Affiliation(s)
- Hina Durrani
- Department of Biomedical Sciences, University of Minnesota School of Medicine, Duluth, USA
| | - James A Bjork
- Department of Biomedical Sciences, University of Minnesota School of Medicine, Duluth, USA
| | - Sara L Zimmer
- Department of Biomedical Sciences, University of Minnesota School of Medicine, Duluth, USA.
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Silva Dias Vieira C, Pinheiro Aguiar R, de Almeida Nogueira NP, Costa dos Santos Junior G, Paes MC. Glucose metabolism sustains heme-induced Trypanosoma cruzi epimastigote growth in vitro. PLoS Negl Trop Dis 2023; 17:e0011725. [PMID: 37948458 PMCID: PMC10664871 DOI: 10.1371/journal.pntd.0011725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 11/22/2023] [Accepted: 10/16/2023] [Indexed: 11/12/2023] Open
Abstract
Chagas disease is caused by the protozoan parasite, Trypanosoma cruzi. This parasite alternates between an insect vector and a mammalian host. T. cruzi epimastigotes reside in the insect vector and coexist with the blood components of the vertebrate host. The metabolic profile of T. cruzi has been extensively studied; however, changes in its metabolism in response to signaling molecules present in the vector are poorly understood. Heme acts as a physiological oxidant that triggers intense epimastigote proliferation and upregulates the expression of genes related to glycolysis and aerobic fermentation in vitro. Here, heme-cultured epimastigotes increased D-glucose consumption. In fact, heme-cultured parasites secreted more succinate (the end product of the so-called succinic fermentation) followed by glucose intake. Increased succinate levels reduced the extracellular pH, leading to acidification of the supernatant. However, the acidification and proliferation stimulated by heme was impaired when glycolysis was inhibited. Otherwise, when glucose amount is enhanced in supernatant, heme-cultured parasites increased its growth whereas the glucose depletion caused a delay in proliferation. Heme supplementation increased epimastigote electron transport system-related O2 consumption rates, while glucose addition reduced both the electron transport system-related O2 consumption rates and spare respiratory capacity, indicating a Crabtree-like effect. These results show that glycolysis predominated in heme-cultured epimastigotes over oxidative phosphorylation for energy supply when glucose is present to sustain its high proliferation in vitro. Furthermore, it provided an insight into the parasite biology in the vector environment that supply glucose and the digestion of blood generates free heme that can lead to the growth of T. cruzi epimastigotes.
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Affiliation(s)
- Carolina Silva Dias Vieira
- Laboratório de Interação Tripanossomatídeos e Vetores—Departamento de Bioquímica, IBRAG–UERJ–Rio de Janeiro, Brazil
| | - Ramon Pinheiro Aguiar
- Institute of Medical Biochemistry Leopoldo de Meis (IBqM) and National Center for Structural Biology and Bioimaging (CENABIO)–UFRJ–Rio de Janeiro, Brazil
| | - Natalia Pereira de Almeida Nogueira
- Laboratório de Interação Tripanossomatídeos e Vetores—Departamento de Bioquímica, IBRAG–UERJ–Rio de Janeiro, Brazil
- Instituto Nacional de Ciência e Tecnologia—Entomologia Molecular (INCT-EM)–Brazil
| | | | - Marcia Cristina Paes
- Laboratório de Interação Tripanossomatídeos e Vetores—Departamento de Bioquímica, IBRAG–UERJ–Rio de Janeiro, Brazil
- Instituto Nacional de Ciência e Tecnologia—Entomologia Molecular (INCT-EM)–Brazil
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Bahrami S, Asadi Z, Zarei M, Hamidinejat H, Henriquez FL. Exposure to sublethal concentrations of chlorine enhances the cytotoxicity of Acanthamoeba castellanii. Parasitol Res 2023; 122:1371-1380. [PMID: 37037947 DOI: 10.1007/s00436-023-07837-z] [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: 11/22/2022] [Accepted: 03/30/2023] [Indexed: 04/12/2023]
Abstract
Free-living amoebae belonging to the genus Acanthamoeba are the causative agents of infections in humans and animals. Many studies are being conducted to find effective compounds against amoebae, but their sublethal concentration effects on surviving amoebae seem to have been overlooked. Chlorine is a common disinfection agent commonly added to public water facilities and supplies. In this study, the cytopathic and phagocytic properties of Acanthamoeba castellanii trophozoites following exposure to sublethal concentrations of chlorine were examined. Two hours of exposure to 5 ppm hypochlorite calcium was considered the sublethal concentration for A. castellanii trophozoites. To compare the pathogenic potential of treated and untreated Acanthamoeba trophozoites, cytotoxicity, adhesion assays in RAW 264.7 macrophages, osmo, and thermotolerance tests were carried out. Bacterial uptake was assessed in treated cells to evaluate their phagocytic characteristics. Oxidative stress biomarkers and antioxidant activities were compared in treated and untreated trophozoites. Finally, the mRNA expression of the mannose-binding protein (MBP), cysteine protease 3 (CP3), and serine endopeptidase (SEP) genes was determined in cells. In all the experiments, untreated trophozoites were considered the control. In comparison to untreated trophozoites, in chlorine-treated trophozoites, cytopathic effects were more extensive and resulted in the detachment of macrophage monolayers. Treated trophozoites could not grow at high temperatures (43 °C). Besides, they showed osmotolerance to 0.5 M D-mannitol but not to 1 M. Results demonstrated a higher bacterial uptake rate by chlorine-treated trophozoites than untreated cells. The treated and untreated cells had significantly different glutathione and glutathione/glutathione disulfide ratios. Antioxidant enzyme activities, total antioxidant capacity, and malondialdehyde levels were increased significantly in chlorine-treated cells. Quantifying mRNA expression in chlorine-treated trophozoites revealed that virulence genes were upregulated. Chlorine can form resistance and virulent amoebae if it is not used at a proper concentration and exposure time. Identification of stress responses, their mechanisms in Acanthamoeba, and their relation to amoeba virulence would give us a better perception of their pathophysiology.
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Affiliation(s)
- Somayeh Bahrami
- Department of Parasitology, Faculty of Veterinary Medicine, Shahid Chamran University of Ahvaz, Ahvaz, Iran.
| | - Zeinab Asadi
- Department of Parasitology, Faculty of Veterinary Medicine, Shahid Chamran University of Ahvaz, Ahvaz, Iran
| | - Mehdi Zarei
- Department of Food Hygiene, Faculty of Veterinary Medicine, Shahid Chamran University of Ahvaz, Ahvaz, Iran
| | - Hossein Hamidinejat
- Department of Parasitology, Faculty of Veterinary Medicine, Shahid Chamran University of Ahvaz, Ahvaz, Iran
| | - Fiona L Henriquez
- Institute of Biomedical and Environmental Health Research, School of Health and Life Sciences, University of the West of Scotland (UWS), Paisley, PA1 2BE, Scotland, UK
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Resisting an invasion: A review of the triatomine vector (Kissing bug) defense strategies against a Trypanosoma sp infection. Acta Trop 2023; 238:106745. [PMID: 36375520 DOI: 10.1016/j.actatropica.2022.106745] [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: 10/06/2022] [Revised: 11/02/2022] [Accepted: 11/04/2022] [Indexed: 11/13/2022]
Abstract
Triatomines are an important group of insects in the Americas. They serve as transmission vectors for Trypanosoma cruzi, the etiologic agent responsible for the deadly Chagas disease in humans. The digenetic parasite has a complex life cycle, alternating between mammalian and insect hosts, facing different environments. In the insect vector, the metacyclic trypomastigote (non-replicative) and epimastigote (replicative) stages face a set of insect-mediated environmental changes, such as intestinal pH, body temperature, nutrient availability, and vector immune response. These insects have the ability to differentiate between self and non-self-particles using their innate immune system. This immune system comprises physical barriers, cellular responses (phagocytosis, nodules and encapsulation), humoral factors, including effector mechanisms (antimicrobial peptides and prophenoloxidase cascade) and the intestinal microbiota. Here, we consolidate and synthesize the available literature to describe the defense mechanisms deployed by the triatomine vector against the parasite, as documented in recent years, the possible mechanisms developed by the parasite to protect against the insect's specific microenvironment and innate immune responses, and future perspectives on the Triatomine-Trypanosome interaction.
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García-Huertas P, Cuesta-Astroz Y, Araque-Ruiz V, Cardona-Castro N. Transcriptional changes during metacyclogenesis of a Colombian Trypanosoma cruzi strain. Parasitol Res 2023; 122:625-634. [PMID: 36567399 DOI: 10.1007/s00436-022-07766-3] [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: 09/08/2022] [Accepted: 12/15/2022] [Indexed: 12/27/2022]
Abstract
During its life cycle, Trypanosoma cruzi undergoes physiological modifications in order to adapt to insect vector and mammalian host conditions. Metacyclogenesis is essential, as the parasite acquires the ability to infect a variety of mammalian species, including humans, in which pathology is caused. In this work, the transcriptomes of metacyclic trypomastigotes and epimastigotes were analyzed in order to identify differentially expressed genes that may be involved in metacyclogenesis. Toward this end, in vitro induction of metacyclogenesis was performed and metacyclic trypomastigotes obtained. RNA-Seq was performed on triplicate samples of epimastigotes and metacyclic trypomastigotes. Differential gene expression analysis showed 513 genes, of which 221 were upregulated and 292 downregulated in metacyclic trypomastigotes. The analysis showed that these genes are related to biological processes relevant in metacyclogenesis. Within these processes, we found that most of the genes associated with infectivity and gene expression regulation were upregulated in metacyclic trypomastigotes, while genes involved in cell division, DNA replication, differentiation, cytoskeleton, and metabolism were mainly downregulated. The participation of some of these genes in T. cruzi metacyclogenesis is of interest, as they may be used as potential therapeutic targets in the design of new drugs for Chagas disease.
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Affiliation(s)
- Paola García-Huertas
- Instituto Colombiano de Medicina Tropical, Universidad CES, CP 055450, Sabaneta, Antioquia, Colombia.
| | - Yesid Cuesta-Astroz
- Instituto Colombiano de Medicina Tropical, Universidad CES, CP 055450, Sabaneta, Antioquia, Colombia
| | - Valentina Araque-Ruiz
- Instituto Colombiano de Medicina Tropical, Universidad CES, CP 055450, Sabaneta, Antioquia, Colombia
| | - Nora Cardona-Castro
- Instituto Colombiano de Medicina Tropical, Universidad CES, CP 055450, Sabaneta, Antioquia, Colombia
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Lima ARJ, Silva HGD, Poubel S, Rosón JN, de Lima LPO, Costa-Silva HM, Gonçalves CS, Galante PAF, Holetz F, Motta MCMM, Silber AM, Elias MC, da Cunha JPC. Open chromatin analysis in Trypanosoma cruzi life forms highlights critical differences in genomic compartments and developmental regulation at tDNA loci. Epigenetics Chromatin 2022; 15:22. [PMID: 35650626 PMCID: PMC9158160 DOI: 10.1186/s13072-022-00450-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 04/18/2022] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Genomic organization and gene expression regulation in trypanosomes are remarkable because protein-coding genes are organized into codirectional gene clusters with unrelated functions. Moreover, there is no dedicated promoter for each gene, resulting in polycistronic gene transcription, with posttranscriptional control playing a major role. Nonetheless, these parasites harbor epigenetic modifications at critical regulatory genome features that dynamically change among parasite stages, which are not fully understood. RESULTS Here, we investigated the impact of chromatin changes in a scenario commanded by posttranscriptional control exploring the parasite Trypanosoma cruzi and its differentiation program using FAIRE-seq approach supported by transmission electron microscopy. We identified differences in T. cruzi genome compartments, putative transcriptional start regions, and virulence factors. In addition, we also detected a developmental chromatin regulation at tRNA loci (tDNA), which could be linked to the intense chromatin remodeling and/or the translation regulatory mechanism required for parasite differentiation. We further integrated the open chromatin profile with public transcriptomic and MNase-seq datasets. Strikingly, a positive correlation was observed between active chromatin and steady-state transcription levels. CONCLUSION Taken together, our results indicate that chromatin changes reflect the unusual gene expression regulation of trypanosomes and the differences among parasite developmental stages, even in the context of a lack of canonical transcriptional control of protein-coding genes.
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Affiliation(s)
- Alex Ranieri Jerônimo Lima
- grid.418514.d0000 0001 1702 8585Laboratório de Ciclo Celular, Instituto Butantan, São Paulo, SP Brazil ,grid.418514.d0000 0001 1702 8585Centro de Toxinas, Resposta Imune E Sinalização Celular (CeTICS), Instituto Butantan, São Paulo, Brazil
| | - Herbert Guimarães de
Sousa Silva
- grid.418514.d0000 0001 1702 8585Laboratório de Ciclo Celular, Instituto Butantan, São Paulo, SP Brazil ,grid.418514.d0000 0001 1702 8585Centro de Toxinas, Resposta Imune E Sinalização Celular (CeTICS), Instituto Butantan, São Paulo, Brazil ,grid.411249.b0000 0001 0514 7202Departamento de Microbiologia, Universidade Federal de São Paulo, Escola Paulista de Medicina, Imunologia E Parasitologia, São Paulo, SP Brazil
| | - Saloe Poubel
- grid.418514.d0000 0001 1702 8585Laboratório de Ciclo Celular, Instituto Butantan, São Paulo, SP Brazil ,grid.418514.d0000 0001 1702 8585Centro de Toxinas, Resposta Imune E Sinalização Celular (CeTICS), Instituto Butantan, São Paulo, Brazil
| | - Juliana Nunes Rosón
- grid.418514.d0000 0001 1702 8585Laboratório de Ciclo Celular, Instituto Butantan, São Paulo, SP Brazil ,grid.418514.d0000 0001 1702 8585Centro de Toxinas, Resposta Imune E Sinalização Celular (CeTICS), Instituto Butantan, São Paulo, Brazil ,grid.411249.b0000 0001 0514 7202Departamento de Microbiologia, Universidade Federal de São Paulo, Escola Paulista de Medicina, Imunologia E Parasitologia, São Paulo, SP Brazil
| | - Loyze Paola Oliveira de Lima
- grid.418514.d0000 0001 1702 8585Laboratório de Ciclo Celular, Instituto Butantan, São Paulo, SP Brazil ,grid.418514.d0000 0001 1702 8585Centro de Toxinas, Resposta Imune E Sinalização Celular (CeTICS), Instituto Butantan, São Paulo, Brazil
| | - Héllida Marina Costa-Silva
- grid.418514.d0000 0001 1702 8585Laboratório de Ciclo Celular, Instituto Butantan, São Paulo, SP Brazil ,grid.418514.d0000 0001 1702 8585Centro de Toxinas, Resposta Imune E Sinalização Celular (CeTICS), Instituto Butantan, São Paulo, Brazil
| | - Camila Silva Gonçalves
- grid.8536.80000 0001 2294 473XLaboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal Do Rio de Janeiro, IBCCF, CCS, UFRJ, Cidade Universitária, Rio de Janeiro, RJ Brazil ,Centro Nacional de Biologia Estrutural E Bioimagem, Rio de Janeiro, RJ Brazil
| | - Pedro A. F. Galante
- grid.413471.40000 0000 9080 8521Centro de Oncologia Molecular, Hospital Sírio Libanês, São Paulo, SP Brazil
| | - Fabiola Holetz
- grid.418068.30000 0001 0723 0931Instituto Carlos Chagas, Fiocruz, Curitiba, PR Brazil
| | - Maria Cristina Machado M. Motta
- grid.8536.80000 0001 2294 473XLaboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal Do Rio de Janeiro, IBCCF, CCS, UFRJ, Cidade Universitária, Rio de Janeiro, RJ Brazil ,Centro Nacional de Biologia Estrutural E Bioimagem, Rio de Janeiro, RJ Brazil
| | - Ariel M. Silber
- grid.11899.380000 0004 1937 0722Universidade de São Paulo, São Paulo, SP Brazil
| | - M. Carolina Elias
- grid.418514.d0000 0001 1702 8585Laboratório de Ciclo Celular, Instituto Butantan, São Paulo, SP Brazil ,grid.418514.d0000 0001 1702 8585Centro de Toxinas, Resposta Imune E Sinalização Celular (CeTICS), Instituto Butantan, São Paulo, Brazil
| | - Julia Pinheiro Chagas da Cunha
- Laboratório de Ciclo Celular, Instituto Butantan, São Paulo, SP, Brazil. .,Centro de Toxinas, Resposta Imune E Sinalização Celular (CeTICS), Instituto Butantan, São Paulo, Brazil.
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In Vitro Validation of Antiparasitic Activity of PLA-Nanoparticles of Sodium Diethyldithiocarbamate against Trypanosoma cruzi. Pharmaceutics 2022; 14:pharmaceutics14030497. [PMID: 35335875 PMCID: PMC8954078 DOI: 10.3390/pharmaceutics14030497] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 02/16/2022] [Accepted: 02/17/2022] [Indexed: 12/19/2022] Open
Abstract
Trypanosoma cruzi is a protozoan parasite responsible for Chagas disease, which affects millions around the world and is not treatable in its chronic stage. Sodium diethyldithiocarbamate is a compound belonging to the carbamate class and, in a previous study, demonstrated high efficacy against T. cruzi, showing itself to be a promising compound for the treatment of Chagas disease. This study investigates the encapsulation of sodium diethyldithiocarbamate by poly-lactic acid in nanoparticles, a system of biodegradable nanoparticles that is capable of reducing the toxicity caused by free DETC against cells and maintaining the antiparasitic activity. The nanosystem PLA-DETC was fabricated using nanoprecipitation, and its physical characterization was measured via DLS, SEM, and AFM, demonstrating a small size around 168 nm and a zeta potential of around −19 mv. Furthermore, the toxicity was determined by MTT reduction against three cell lines (VERO, 3T3, and RAW), and when compared to free DETC, we observed a reduction in cell mortality, demonstrating the importance of DETC nanoencapsulation. In addition, the nanoparticles were stained with FITC and put in contact with cells for 24 h, followed by confirmation of whether the nanosystem was inside the cells. Lastly, the antiparasitic activity against different strains of T. cruzi in trypomastigote forms was determined by resazurin reduction and ROS production, which demonstrated high efficacy towards T. cruzi equal to that of free DETC.
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Dave N, Cetiner U, Arroyo D, Fonbuena J, Tiwari M, Barrera P, Lander N, Anishkin A, Sukharev S, Jimenez V. A novel mechanosensitive channel controls osmoregulation, differentiation, and infectivity in Trypanosoma cruzi. eLife 2021; 10:67449. [PMID: 34212856 PMCID: PMC8282336 DOI: 10.7554/elife.67449] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Accepted: 07/01/2021] [Indexed: 12/19/2022] Open
Abstract
The causative agent of Chagas disease undergoes drastic morphological and biochemical modifications as it passes between hosts and transitions from extracellular to intracellular stages. The osmotic and mechanical aspects of these cellular transformations are not understood. Here we identify and characterize a novel mechanosensitive channel in Trypanosoma cruzi (TcMscS) belonging to the superfamily of small-conductance mechanosensitive channels (MscS). TcMscS is activated by membrane tension and forms a large pore permeable to anions, cations, and small osmolytes. The channel changes its location from the contractile vacuole complex in epimastigotes to the plasma membrane as the parasites develop into intracellular amastigotes. TcMscS knockout parasites show significant fitness defects, including increased cell volume, calcium dysregulation, impaired differentiation, and a dramatic decrease in infectivity. Our work provides mechanistic insights into components supporting pathogen adaptation inside the host, thus opening the exploration of mechanosensation as a prerequisite for protozoan infectivity.
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Affiliation(s)
- Noopur Dave
- Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, United States
| | - Ugur Cetiner
- Department of Biology, University of Maryland, College Park, United States
| | - Daniel Arroyo
- Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, United States
| | - Joshua Fonbuena
- Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, United States
| | - Megna Tiwari
- Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, United States
| | - Patricia Barrera
- Departmento de Biología, Facultad de Ciencias Exactas y Naturales, Instituto de Histologia y Embriologia IHEM-CONICET, Facultad de Medicina, Universidad Nacional de Cuyo, Mendoza, Argentina
| | - Noelia Lander
- Department of Biological Sciences, University of Cincinnati, Cincinnati, United States
| | - Andriy Anishkin
- Department of Biology, University of Maryland, College Park, United States
| | - Sergei Sukharev
- Department of Biology, University of Maryland, College Park, United States
| | - Veronica Jimenez
- Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, United States
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Costa-Silva HM, Resende BC, Umaki ACS, Prado W, da Silva MS, Virgílio S, Macedo AM, Pena SDJ, Tahara EB, Tosi LRO, Elias MC, Andrade LO, Reis-Cunha JL, Franco GR, Fragoso SP, Machado CR. DNA Topoisomerase 3α Is Involved in Homologous Recombination Repair and Replication Stress Response in Trypanosoma cruzi. Front Cell Dev Biol 2021; 9:633195w. [PMID: 34055812 PMCID: PMC8155511 DOI: 10.3389/fcell.2021.633195] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Accepted: 03/19/2021] [Indexed: 12/30/2022] Open
Abstract
DNA topoisomerases are enzymes that modulate DNA topology. Among them, topoisomerase 3α is engaged in genomic maintenance acting in DNA replication termination, sister chromatid separation, and dissolution of recombination intermediates. To evaluate the role of this enzyme in Trypanosoma cruzi, the etiologic agent of Chagas disease, a topoisomerase 3α knockout parasite (TcTopo3α KO) was generated, and the parasite growth, as well as its response to several DNA damage agents, were evaluated. There was no growth alteration caused by the TcTopo3α knockout in epimastigote forms, but a higher dormancy rate was observed. TcTopo3α KO trypomastigote forms displayed reduced invasion rates in LLC-MK2 cells when compared with the wild-type lineage. Amastigote proliferation was also compromised in the TcTopo3α KO, and a higher number of dormant cells was observed. Additionally, TcTopo3α KO epimastigotes were not able to recover cell growth after gamma radiation exposure, suggesting the involvement of topoisomerase 3α in homologous recombination. These parasites were also sensitive to drugs that generate replication stress, such as cisplatin (Cis), hydroxyurea (HU), and methyl methanesulfonate (MMS). In response to HU and Cis treatments, TcTopo3α KO parasites showed a slower cell growth and was not able to efficiently repair the DNA damage induced by these genotoxic agents. The cell growth phenotype observed after MMS treatment was similar to that observed after gamma radiation, although there were fewer dormant cells after MMS exposure. TcTopo3α KO parasites showed a population with sub-G1 DNA content and strong γH2A signal 48 h after MMS treatment. So, it is possible that DNA-damaged cell proliferation due to the absence of TcTopo3α leads to cell death. Whole genome sequencing of MMS-treated parasites showed a significant reduction in the content of the multigene families DFG-1 and RHS, and also a possible erosion of the sub-telomeric region from chromosome 22, relative to non-treated knockout parasites. Southern blot experiments suggest telomere shortening, which could indicate genomic instability in TcTopo3α KO cells owing to MMS treatment. Thus, topoisomerase 3α is important for homologous recombination repair and replication stress in T. cruzi, even though all the pathways in which this enzyme participates during the replication stress response remains elusive.
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Affiliation(s)
- Héllida Marina Costa-Silva
- Laboratório de Genética Bioquímica, Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Bruno Carvalho Resende
- Laboratório de Genética Bioquímica, Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Adriana Castilhos Souza Umaki
- Laboratório de Biologia Molecular e Sistêmica de Tripanossomatídeos, Instituto Carlos Chagas, Fundação Oswaldo Cruz (FIOCRUZ), Curitiba, Brazil
| | - Willian Prado
- Laboratório de Genética Bioquímica, Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Marcelo Santos da Silva
- Laboratório de Ciclo Celular, Centro de Toxinas, Resposta Imune e Sinalização Celular, Instituto Butantan, São Paulo, Brazil
| | - Stela Virgílio
- Laboratório de Biologia Molecular de Leishmanias, Departamento de Biologia Celular e Molecular e Bioagentes Patogênicos, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo (USP), Ribeirão Preto, Brazil
| | - Andrea Mara Macedo
- Laboratório de Genética Bioquímica, Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Sérgio Danilo Junho Pena
- Laboratório de Genética Bioquímica, Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Erich Birelli Tahara
- Laboratório de Genética Bioquímica, Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Luiz Ricardo Orsini Tosi
- Laboratório de Biologia Molecular de Leishmanias, Departamento de Biologia Celular e Molecular e Bioagentes Patogênicos, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo (USP), Ribeirão Preto, Brazil
| | - Maria Carolina Elias
- Laboratório de Ciclo Celular, Centro de Toxinas, Resposta Imune e Sinalização Celular, Instituto Butantan, São Paulo, Brazil
| | - Luciana Oliveira Andrade
- Laboratório de Biologia Celular e Molecular, Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - João Luís Reis-Cunha
- Departamento de Medicina Veterinária Preventiva, Escola de Veterinária, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Glória Regina Franco
- Laboratório de Genética Bioquímica, Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Stenio Perdigão Fragoso
- Laboratório de Biologia Molecular e Sistêmica de Tripanossomatídeos, Instituto Carlos Chagas, Fundação Oswaldo Cruz (FIOCRUZ), Curitiba, Brazil
| | - Carlos Renato Machado
- Laboratório de Genética Bioquímica, Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
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10
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Melo RDFP, Guarneri AA, Silber AM. The Influence of Environmental Cues on the Development of Trypanosoma cruzi in Triatominae Vector. Front Cell Infect Microbiol 2020; 10:27. [PMID: 32154185 PMCID: PMC7046586 DOI: 10.3389/fcimb.2020.00027] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Accepted: 01/15/2020] [Indexed: 12/19/2022] Open
Abstract
Trypanosoma cruzi, a hemoflagellate parasite, is the etiological agent of Chagas disease that affects about 6-7 million people worldwide, mostly in Latin America. The parasite life cycle is complex and alternates between an invertebrate host-Triatominae vector-and a mammalian host. The parasite adaptation to the several microenvironments through which it transits is critical to success in establishing infection. Moreover, environmental cues also play an important role on the parasite development, and it can modulate the infection. In the present study, we discussed how the temperature oscillations and the nutritional state of the invertebrate host can affect the parasite development, multiplication, and the differentiation process of epimastigote forms into metacyclic trypomastigotes, called metacyclogenesis. The impact of oxidative imbalance and osmotic stresses on the parasite-vector relationship are also discussed.
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Affiliation(s)
- Raíssa de Fátima Pimentel Melo
- Laboratório de Bioquímica de Tryps (LaBTryps), Departamento de Parasitologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
| | - Alessandra Aparecida Guarneri
- Vector Behaviour and Pathogen Interaction Group, Instituto René Rachou, Fundação Oswaldo Cruz, Belo Horizonte, Brazil
| | - Ariel Mariano Silber
- Laboratório de Bioquímica de Tryps (LaBTryps), Departamento de Parasitologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
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11
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Barrera P, Skorka C, Boktor M, Dave N, Jimenez V. A Novel Calcium-Activated Potassium Channel Controls Membrane Potential and Intracellular pH in Trypanosoma cruzi. Front Cell Infect Microbiol 2020; 9:464. [PMID: 32010643 PMCID: PMC6974456 DOI: 10.3389/fcimb.2019.00464] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Accepted: 12/16/2019] [Indexed: 12/13/2022] Open
Abstract
Trypanosoma cruzi develops in environments where nutrient availability, osmolarity, ionic concentrations, and pH undergo significant changes. The ability to adapt and respond to such conditions determines the survival and successful transmission of T. cruzi. Ion channels play fundamental roles in controlling physiological parameters that ensure cell homeostasis by rapidly triggering compensatory mechanisms. Combining molecular, cellular and electrophysiological approaches we have identified and characterized the expression and function of a novel calcium-activated potassium channel (TcCAKC). This channel resides in the plasma membrane of all 3 life stages of T. cruzi and shares structural features with other potassium channels. We expressed TcCAKC in Xenopus laevis oocytes and established its biophysical properties by two-electrode voltage clamp. Oocytes expressing TcCAKC showed a significant increase in inward currents after addition of calcium ionophore ionomycin or thapsigargin. These responses were abolished by EGTA suggesting that TcCAKC activation is dependent of extracellular calcium. This activation causes an increase in current and a negative shift in reversal potential that is blocked by barium. As predicted, a single point mutation in the selectivity filter (Y313A) completely abolished the activity of the channels, confirming its potassium selective nature. We have generated knockout parasites deleting one or both alleles of TcCAKC. These parasite strains showed impaired growth, decreased production of trypomastigotes and slower intracellular replication, pointing to an important role of TcCAKC in regulating infectivity. To understand the cellular mechanisms underlying these phenotypic defects, we used fluorescent probes to evaluate intracellular membrane potential, pH, and intracellular calcium. Epimastigotes lacking the channel had significantly lower cytosolic calcium, hyperpolarization, changes in intracellular pH, and increased rate of proton extrusion. These results are in agreement with previous reports indicating that, in trypanosomatids, membrane potential and intracellular pH maintenance are linked. Our work shows TcCAKC is a novel potassium channel that contributes to homeostatic regulation of important physiological processes in T. cruzi and provides new avenues to explore the potential of ion channels as targets for drug development against protozoan parasites.
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Affiliation(s)
- Patricia Barrera
- Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, CA, United States
| | - Christopher Skorka
- Departmento de Biología, Facultad de Ciencias Exactas y Naturales, Instituto de Histologia y Embriologia IHEM-CONICET, Facultad de Medicina, Universidad Nacional de Cuyo, Mendoza, Argentina
| | - Michael Boktor
- Departmento de Biología, Facultad de Ciencias Exactas y Naturales, Instituto de Histologia y Embriologia IHEM-CONICET, Facultad de Medicina, Universidad Nacional de Cuyo, Mendoza, Argentina
| | - Noopur Dave
- Departmento de Biología, Facultad de Ciencias Exactas y Naturales, Instituto de Histologia y Embriologia IHEM-CONICET, Facultad de Medicina, Universidad Nacional de Cuyo, Mendoza, Argentina
| | - Veronica Jimenez
- Departmento de Biología, Facultad de Ciencias Exactas y Naturales, Instituto de Histologia y Embriologia IHEM-CONICET, Facultad de Medicina, Universidad Nacional de Cuyo, Mendoza, Argentina
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12
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Paes MC, Saraiva FMS, Nogueira NP, Vieira CSD, Dias FA, Rossini A, Coelho VL, Pane A, Sang F, Alcocer M. Gene expression profiling of Trypanosoma cruzi in the presence of heme points to glycosomal metabolic adaptation of epimastigotes inside the vector. PLoS Negl Trop Dis 2020; 14:e0007945. [PMID: 31895927 PMCID: PMC6959606 DOI: 10.1371/journal.pntd.0007945] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2019] [Revised: 01/14/2020] [Accepted: 11/22/2019] [Indexed: 11/18/2022] Open
Abstract
Chagas disease, also known as American trypanosomiasis, is a potentially life-threatening illness caused by the protozoan parasite, Trypanosoma cruzi, and is transmitted by triatomine insects during its blood meal. Proliferative epimastigotes forms thrive inside the insects in the presence of heme (iron protoporphyrin IX), an abundant product of blood digestion, however little is known about the metabolic outcome of this signaling molecule in the parasite. Trypanosomatids exhibit unusual gene transcription employing a polycistronic transcription mechanism through trans-splicing that regulates its life cycle. Using the Deep Seq transcriptome sequencing we characterized the heme induced transcriptome of epimastigotes and determined that most of the upregulated genes were related to glucose metabolism inside the glycosomes. These results were supported by the upregulation of glycosomal isoforms of PEPCK and fumarate reductase of heme-treated parasites, implying that the fermentation process was favored. Moreover, the downregulation of mitochondrial gene enzymes in the presence of heme also supported the hypothesis that heme shifts the parasite glycosomal glucose metabolism towards aerobic fermentation. These results are examples of the environmental metabolic plasticity inside the vector supporting ATP production, promoting epimastigotes proliferation and survival.
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Affiliation(s)
- Marcia C. Paes
- Laboratório de Interação Tripanossomatídeos e Vetores—Departamento de Bioquímica, IBRAG–UERJ–Rio de Janeiro, Brazil
- Instituto Nacional de Ciência e Tecnologia—Entomologia Molecular (INCT-EM)–Brazil
- * E-mail: (MCP); (MA)
| | - Francis M. S. Saraiva
- Laboratório de Interação Tripanossomatídeos e Vetores—Departamento de Bioquímica, IBRAG–UERJ–Rio de Janeiro, Brazil
| | - Natália P. Nogueira
- Laboratório de Interação Tripanossomatídeos e Vetores—Departamento de Bioquímica, IBRAG–UERJ–Rio de Janeiro, Brazil
- Instituto Nacional de Ciência e Tecnologia—Entomologia Molecular (INCT-EM)–Brazil
| | - Carolina S. D. Vieira
- Laboratório de Interação Tripanossomatídeos e Vetores—Departamento de Bioquímica, IBRAG–UERJ–Rio de Janeiro, Brazil
| | - Felipe A. Dias
- Instituto Nacional de Ciência e Tecnologia—Entomologia Molecular (INCT-EM)–Brazil
- Laboratório de Bioquímica de Artrópodes Hematófagos, Instituto de Bioquímica Médica, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Ana Rossini
- Laboratório de Toxicologia e Biologia Molecular, Departamento de Bioquímica, IBRAG- UERJ- Rio de Janeiro, Brazil
| | - Vitor Lima Coelho
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Attilio Pane
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Fei Sang
- Deep Seq, School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Marcos Alcocer
- School of Biosciences, University of Nottingham, United Kingdom
- * E-mail: (MCP); (MA)
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13
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Talevi A, Carrillo C, Comini M. The Thiol-polyamine Metabolism of Trypanosoma cruzi: Molecular Targets and Drug Repurposing Strategies. Curr Med Chem 2019; 26:6614-6635. [PMID: 30259812 DOI: 10.2174/0929867325666180926151059] [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: 05/04/2018] [Revised: 07/23/2018] [Accepted: 09/10/2018] [Indexed: 12/18/2022]
Abstract
Chagas´ disease continues to be a challenging and neglected public health problem in many American countries. The etiologic agent, Trypanosoma cruzi, develops intracellularly in the mammalian host, which hinders treatment efficacy. Progress in the knowledge of parasite biology and host-pathogen interaction has not been paralleled by the development of novel, safe and effective therapeutic options. It is then urgent to seek for novel therapeutic candidates and to implement drug discovery strategies that may accelerate the discovery process. The most appealing targets for pharmacological intervention are those essential for the pathogen and, whenever possible, absent or significantly different from the host homolog. The thiol-polyamine metabolism of T. cruzi offers interesting candidates for a rational design of selective drugs. In this respect, here we critically review the state of the art of the thiolpolyamine metabolism of T. cruzi and the pharmacological potential of its components. On the other hand, drug repurposing emerged as a valid strategy to identify new biological activities for drugs in clinical use, while significantly shortening the long time and high cost associated with de novo drug discovery approaches. Thus, we also discuss the different drug repurposing strategies available with a special emphasis in their applications to the identification of drug candidates targeting essential components of the thiol-polyamine metabolism of T. cruzi.
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Affiliation(s)
- Alan Talevi
- Medicinal Chemistry, Department of Biological Sciences, Faculty of Exact Sciences, University of La Plata, La Plata, Argentina
| | - Carolina Carrillo
- Instituto de Ciencias y Tecnología Dr. César Milstein (ICT Milstein) - CONICET. Ciudad Autónoma de Buenos Aires, Argentina
| | - Marcelo Comini
- Institut Pasteur de Montevideo, Mataojo 2020, Montevideo 11400, Uruguay
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14
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Torres-Gutiérrez E, Pérez-Cervera Y, Camoin L, Zenteno E, Aquino-Gil MO, Lefebvre T, Cabrera-Bravo M, Reynoso-Ducoing O, Bucio-Torres MI, Salazar-Schettino PM. Identification of O-Glcnacylated Proteins in Trypanosoma cruzi. Front Endocrinol (Lausanne) 2019; 10:199. [PMID: 30984116 PMCID: PMC6449728 DOI: 10.3389/fendo.2019.00199] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Accepted: 03/11/2019] [Indexed: 01/16/2023] Open
Abstract
Originally an anthropozoonosis in the Americas, Chagas disease has spread from its previous borders through migration. It is caused by the protozoan Trypanosoma cruzi. Differences in disease severity have been attributed to a natural pleomorphism in T. cruzi. Several post-translational modifications (PTMs) have been studied in T. cruzi, but to date no work has focused on O-GlcNAcylation, a highly conserved monosaccharide-PTM of serine and threonine residues mainly found in nucleus, cytoplasm, and mitochondrion proteins. O-GlcNAcylation is thought to regulate protein function analogously to protein phosphorylation; indeed, crosstalk between both PTMs allows the cell to regulate its functions in response to nutrient levels and stress. Herein, we demonstrate O-GlcNAcylation in T. cruzi epimastigotes by three methods: by using specific antibodies against the modification in lysates and whole parasites, by click chemistry labeling, and by proteomics. In total, 1,271 putative O-GlcNAcylated proteins and six modification sequences were identified by mass spectrometry (data available via ProteomeXchange, ID PXD010285). Most of these proteins have structural and metabolic functions that are essential for parasite survival and evolution. Furthermore, O-GlcNAcylation pattern variations were observed by antibody detection under glucose deprivation and heat stress conditions, supporting their possible role in the adaptive response. Given the numerous biological processes in which O-GlcNAcylated proteins participate, its identification in T. cruzi proteins opens a new research field in the biology of Trypanosomatids, improve our understanding of infection processes and may allow us to identify new therapeutic targets.
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Affiliation(s)
- Elia Torres-Gutiérrez
- Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad de México, Mexico
| | - Yobana Pérez-Cervera
- Centro de Investigación Facultad de Medicina-UNAM and Facultad de Odontología, Universidad Autónoma Benito Juárez de Oaxaca, Oaxaca, Mexico
| | - Luc Camoin
- INSERM, Institut Paoli-Calmetes, CRCM, Marseille Protéomique, Aix-Marseille Univ, Marseille, France
| | - Edgar Zenteno
- Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad de México, Mexico
| | - Moyira Osny Aquino-Gil
- Centro de Investigación Facultad de Medicina-UNAM and Facultad de Odontología, Universidad Autónoma Benito Juárez de Oaxaca, Oaxaca, Mexico
- Instituto Tecnológico de Oaxaca, Tecnológico Nacional de Mexico, Oaxaca, Mexico
- CNRS, UMR 8576, UGSF, Unité de Glycobiologie Structurale et Fonctionnelle, Université de Lille, Lille, France
| | - Tony Lefebvre
- CNRS, UMR 8576, UGSF, Unité de Glycobiologie Structurale et Fonctionnelle, Université de Lille, Lille, France
| | | | | | - Martha Irene Bucio-Torres
- Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad de México, Mexico
- *Correspondence: Martha Irene Bucio-Torres
| | - Paz María Salazar-Schettino
- Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad de México, Mexico
- Paz María Salazar-Schettino
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15
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Alves CL, Repolês BM, da Silva MS, Mendes IC, Marin PA, Aguiar PHN, Santos SDS, Franco GR, Macedo AM, Pena SDJ, Andrade LDO, Guarneri AA, Tahara EB, Elias MC, Machado CR. The recombinase Rad51 plays a key role in events of genetic exchange in Trypanosoma cruzi. Sci Rep 2018; 8:13335. [PMID: 30190603 PMCID: PMC6127316 DOI: 10.1038/s41598-018-31541-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Accepted: 08/16/2018] [Indexed: 12/11/2022] Open
Abstract
Detection of genetic exchange has been a limiting factor to deepen the knowledge on the mechanisms by which Trypanosoma cruzi is able to generate progeny and genetic diversity. Here we show that incorporation of halogenated thymidine analogues, followed by immunostaining, is a reliable method not only to detect T. cruzi fused-cell hybrids, but also to quantify their percentage in populations of this parasite. Through this approach, we were able to detect and quantify fused-cell hybrids of T. cruzi clones CL Brener and Y. Given the increased detection of fused-cell hybrids in naturally-occurring hybrid CL Brener strain, which displays increased levels of RAD51 and BRCA2 transcripts, we further investigated the role of Rad51 - a recombinase involved in homologous recombination - in the process of genetic exchange. We also verified that the detection of fused-cell hybrids in T. cruzi overexpressing RAD51 is increased when compared to wild-type cells, suggesting a key role for Rad51 either in the formation or in the stabilization of fused-cell hybrids in this organism.
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Affiliation(s)
- Ceres Luciana Alves
- Departamento de Bioquímica e Imunologia, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Bruno Marçal Repolês
- Departamento de Bioquímica e Imunologia, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Marcelo Santos da Silva
- Laboratório Especial de Ciclo Celular, Centro de Toxinas, Resposta Imune e Sinalização Celular, Instituto Butantan, São Paulo, SP, Brazil
| | - Isabela Cecília Mendes
- Departamento de Bioquímica e Imunologia, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Paula Andrea Marin
- Laboratório Especial de Ciclo Celular, Centro de Toxinas, Resposta Imune e Sinalização Celular, Instituto Butantan, São Paulo, SP, Brazil
| | | | - Selma da Silva Santos
- Departamento de Bioquímica e Imunologia, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Glória Regina Franco
- Departamento de Bioquímica e Imunologia, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Andréa Mara Macedo
- Departamento de Bioquímica e Imunologia, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Sérgio Danilo Junho Pena
- Departamento de Bioquímica e Imunologia, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | | | | | - Erich Birelli Tahara
- Departamento de Bioquímica e Imunologia, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Maria Carolina Elias
- Laboratório Especial de Ciclo Celular, Centro de Toxinas, Resposta Imune e Sinalização Celular, Instituto Butantan, São Paulo, SP, Brazil
| | - Carlos Renato Machado
- Departamento de Bioquímica e Imunologia, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
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16
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Kalem MC, Gerasimov ES, Vu PK, Zimmer SL. Gene expression to mitochondrial metabolism: Variability among cultured Trypanosoma cruzi strains. PLoS One 2018; 13:e0197983. [PMID: 29847594 PMCID: PMC5976161 DOI: 10.1371/journal.pone.0197983] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Accepted: 05/11/2018] [Indexed: 11/18/2022] Open
Abstract
The insect-transmitted protozoan parasite Trypanosoma cruzi experiences changes in nutrient availability and rate of flux through different metabolic pathways across its life cycle. The species encompasses much genetic diversity of both the nuclear and mitochondrial genomes among isolated strains. The genetic or expression variation of both genomes are likely to impact metabolic responses to environmental stimuli, and even steady state metabolic function, among strains. To begin formal characterization these differences, we compared aspects of metabolism between genetically similar strains CL Brener and Tulahuen with less similar Esmeraldo and Sylvio X10 strains in a culture environment. Epimastigotes of all strains took up glucose at similar rates. However, the degree of medium acidification that could be observed when glucose was absent from the medium varied by strain, indicating potential differences in excreted metabolic byproducts. Our main focus was differences related to electron transport chain function. We observed differences in ATP-coupled respiration and maximal respiratory capacity, mitochondrial membrane potential, and mitochondrial morphology between strains, despite the fact that abundances of two nuclear-encoded proteins of the electron transport chain are similar between strains. RNA sequencing reveals strain-specific differences in abundances of mRNAs encoding proteins of the respiratory chain but also other metabolic processes. From these differences in metabolism and mitochondrial phenotypes we have generated tentative models for the differential metabolic fluxes or differences in gene expression that may underlie these results.
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Affiliation(s)
- Murat C. Kalem
- Department of Biology, University of Minnesota Duluth, Duluth, Minnesota, United States of America
- Department of Biomedical Sciences, University of Minnesota Medical School, Duluth campus, Duluth, Minnesota, United States of America
| | | | - Pamela K. Vu
- Department of Biology, University of Minnesota Duluth, Duluth, Minnesota, United States of America
| | - Sara L. Zimmer
- Department of Biomedical Sciences, University of Minnesota Medical School, Duluth campus, Duluth, Minnesota, United States of America
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17
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The Trypanosoma cruzi RNA-binding protein RBP42 is expressed in the cytoplasm throughout the life cycle of the parasite. Parasitol Res 2018; 117:1095-1104. [PMID: 29473141 DOI: 10.1007/s00436-018-5787-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Accepted: 01/25/2018] [Indexed: 01/12/2023]
Abstract
Trypanosoma cruzi, the protozoan parasite that causes Chagas disease in humans, has a complex life cycle that promotes survival in disparate environments. In each environment, the parasite must fine-tune its metabolic pathways to divide and multiply. In the absence of recognizable transcriptional gene regulation, it is apparent that protein levels are determined by post-transcriptional mechanisms. Post-transcriptional gene control is influenced by RNA-binding proteins that target mRNAs in the cell's cytoplasm. To initiate the study of post-transcriptional activities in T. cruzi, we studied this organism's ortholog of RBP42, a trypanosomal RNA-binding protein. RBP42 was originally detected in Trypanosoma brucei and was shown to target a subset of mRNAs that encode proteins governing central carbon metabolism. T. cruzi RBP42 structurally resembles T. brucei RBP42, sharing an NTF2 domain at its amino terminus and a single RNA-binding domain (specifically, the RNA recognition motif, or RRM), at its carboxy terminus. A phylogenetic analysis reveals that an NTF2 and a single RRM are distinguishing features of all RBP42 orthologs within the broad kinetoplastid grouping. T. cruzi RBP42 is expressed in all life cycle stages of the parasite as determined by immunoblot and immunofluorescence microscopy. In each case, the protein is localized to the cytoplasm, indicating a role for T. cruzi RBP42 in post-transcriptional activities in all stages of the parasite life cycle. We speculate that RBP42 influences the dynamic metabolic pathways responsible for parasite infection and transmission.
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18
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Gonçalves CS, Ávila AR, de Souza W, Motta MCM, Cavalcanti DP. Revisiting the Trypanosoma cruzi metacyclogenesis: morphological and ultrastructural analyses during cell differentiation. Parasit Vectors 2018; 11:83. [PMID: 29409544 PMCID: PMC5801705 DOI: 10.1186/s13071-018-2664-4] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Accepted: 01/22/2018] [Indexed: 11/30/2022] Open
Abstract
Background Trypanosoma cruzi uses several strategies to survive in different hosts. A key step in the life-cycle of this parasite is metacyclogenesis, which involves various morphological, biochemical, and genetic changes that induce the differentiation of non-pathogenic epimastigotes into pathogenic metacyclic trypomastigotes. During metacyclogenesis, T. cruzi displays distinct morphologies and ultrastructural features, which have not been fully characterized. Results We performed a temporal description of metacyclogenesis using different microscopy techniques that resulted in the identification of three intermediate forms of T. cruzi: intermediates I, II and III. Such classification was based on morphological and ultrastructural aspects as the location of the kinetoplast in relation to the nucleus, kinetoplast shape and kDNA topology. Furthermore, we suggested that metacyclic trypomastigotes derived from intermediate forms that had already detached from the substrate. We also found that changes in the kinetoplast morphology and kDNA arrangement occurred only after the repositioning of this structure toward the posterior region of the cell body. These changes occurred during the later stages of differentiation. In contrast, changes in the nucleus shape began as soon as metacyclogenesis was initiated, while changes in nuclear ultrastructure, such as the loss of the nucleolus, were only observed during later stages of differentiation. Finally, we found that kDNA networks of distinct T. cruzi forms present different patterns of DNA topology. Conclusions Our study of T. cruzi metacyclogenesis revealed important aspects of the morphology and ultrastructure of this intriguing cell differentiation process. This research expands our understanding of this parasite’s fascinating life-cycle. It also highlights the study of T. cruzi as an important and exciting model system for investigating diverse aspects of cellular, molecular, and evolutionary biology.
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Affiliation(s)
- Camila Silva Gonçalves
- Laboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, UFRJ, Rio de Janeiro, RJ, Brazil.,Laboratório de Microbiologia, Diretoria de Metrologia Aplicada às Ciências da Vida, Instituto Nacional de Metrologia, Qualidade e Tecnologia- Inmetro, Rio de Janeiro, RJ, Brazil
| | - Andrea Rodrigues Ávila
- Laboratório de Regulação da Expressão Gênica, Instituto Carlos Chagas, FIOCRUZ, Curitiba, PR, Brazil
| | - Wanderley de Souza
- Laboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, UFRJ, Rio de Janeiro, RJ, Brazil.,Instituto Nacional de Ciência e Tecnologia de Biologia Estrutural e Bioimagem, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Maria Cristina M Motta
- Laboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, UFRJ, Rio de Janeiro, RJ, Brazil.,Instituto Nacional de Ciência e Tecnologia de Biologia Estrutural e Bioimagem, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Danielle Pereira Cavalcanti
- Laboratório de Microbiologia, Diretoria de Metrologia Aplicada às Ciências da Vida, Instituto Nacional de Metrologia, Qualidade e Tecnologia- Inmetro, Rio de Janeiro, RJ, Brazil. .,Instituto Nacional de Ciência e Tecnologia de Biologia Estrutural e Bioimagem, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
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19
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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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Lechuga GC, Borges JC, Calvet CM, de Araújo HP, Zuma AA, do Nascimento SB, Motta MCM, Bernardino AMR, Pereira MCDS, Bourguignon SC. Interactions between 4-aminoquinoline and heme: Promising mechanism against Trypanosoma cruzi. Int J Parasitol Drugs Drug Resist 2016; 6:154-164. [PMID: 27490082 PMCID: PMC4971285 DOI: 10.1016/j.ijpddr.2016.07.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Revised: 06/25/2016] [Accepted: 07/12/2016] [Indexed: 02/07/2023]
Abstract
Chagas disease is a neglected tropical disease caused by the flagellated protozoan Trypanosoma cruzi. The current drugs used to treat this disease have limited efficacy and produce severe side effects. Quinolines, nitrogen heterocycle compounds that form complexes with heme, have a broad spectrum of antiprotozoal activity and are a promising class of new compounds for Chagas disease chemotherapy. In this study, we evaluated the activity of a series of 4-arylaminoquinoline-3-carbonitrile derivatives against all forms of Trypanosoma cruzi in vitro. Compound 1g showed promising activity against epimastigote forms when combined with hemin (IC50<1 μM), with better performance than benznidazole, the reference drug. This compound also inhibited the viability of trypomastigotes and intracellular amastigotes. The potency of 1g in combination with heme was enhanced against epimastigotes and trypomastigotes, suggesting a similar mechanism of action that occurs in Plasmodium spp. The addition of hemin to the culture medium increased trypanocidal activity of analog 1g without changing the cytotoxicity of the host cell, reaching an IC50 of 11.7 μM for trypomastigotes. The mechanism of action was demonstrated by the interaction of compound 1g with hemin in solution and prevention of heme peroxidation. Compound 1g and heme treatment induced alterations of the mitochondrion-kinetoplast complex in epimastigotes and trypomastigotes and also, accumulation of electron-dense deposits in amastigotes as visualized by transmission electron microscopy. The trypanocidal activity of 4-aminoquinolines and the elucidation of the mechanism involving interaction with heme is a neglected field of research, given the parasite's lack of heme biosynthetic pathway and the importance of this cofactor for parasite survival and growth. The results of this study can improve and guide rational drug development and combination treatment strategies.
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Affiliation(s)
- Guilherme Curty Lechuga
- Laboratório de Interação celular e molecular, Departamento de Biologia Celular e Molecular, Universidade Federal Fluminense, Rua Outeiro São João Batista, 24020-141, Niterói, Rio de Janeiro, Brazil
| | - Júlio Cesar Borges
- Departamento de Química Orgânica, Universidade Federal Fluminense, Rua Outeiro São João Batista, 24020-141, Niterói, Rio de Janeiro, Brazil; Instituto Federal de Educação, Ciência e Tecnologia do Rio de Janeiro, Campus Nilópolis, 26530-060, RJ, Brazil
| | - Claudia Magalhães Calvet
- Laboratório de Ultraestrutura Celular, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Avenida Brasil 4365, 21040-360, Rio de Janeiro, RJ, Brazil
| | - Humberto Pinheiro de Araújo
- Departamento de Imunologia, Instituto Nacional de Controle de Qualidade em Saúde, Fundação Oswaldo Cruz, Avenida Brasil 4365, 21040-360, Rio de Janeiro, RJ, Brazil
| | - Aline Araujo Zuma
- Laboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Avenida Carlos Chagas Filho, 373-bloco G. Cidade Universitária, Ilha do Fundão, Rio de Janeiro, RJ, Brazil
| | - Samara Braga do Nascimento
- Laboratório de Interação celular e molecular, Departamento de Biologia Celular e Molecular, Universidade Federal Fluminense, Rua Outeiro São João Batista, 24020-141, Niterói, Rio de Janeiro, Brazil
| | - Maria Cristina Machado Motta
- Laboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Avenida Carlos Chagas Filho, 373-bloco G. Cidade Universitária, Ilha do Fundão, Rio de Janeiro, RJ, Brazil
| | | | - Mirian Claudia de Souza Pereira
- Laboratório de Ultraestrutura Celular, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Avenida Brasil 4365, 21040-360, Rio de Janeiro, RJ, Brazil.
| | - Saulo Cabral Bourguignon
- Laboratório de Interação celular e molecular, Departamento de Biologia Celular e Molecular, Universidade Federal Fluminense, Rua Outeiro São João Batista, 24020-141, Niterói, Rio de Janeiro, Brazil.
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Mitochondrial Gene Expression Is Responsive to Starvation Stress and Developmental Transition in Trypanosoma cruzi. mSphere 2016; 1:mSphere.00051-16. [PMID: 27303725 PMCID: PMC4894683 DOI: 10.1128/msphere.00051-16] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 03/23/2016] [Indexed: 01/22/2023] Open
Abstract
Chagas disease is caused by insect-transmitted Trypanosoma cruzi. Halting T. cruzi’s life cycle in one of its various human and insect life stages would effectively stop the parasite’s infection cycle. T. cruzi is exposed to a variety of environmental conditions in its different life stages, and gene expression must be remodeled to survive these changes. In this work, we look at the impact that one of these changes, nutrient depletion, has on the expression of the 20 gene products encoded in the mitochondrial genome that is neglected by whole-genome studies. We show increases in mitochondrial RNA abundances in starved insect-stage cells, under two conditions in which transition to the infectious stage occurs or does not. This report is the first to show that T. cruzi mitochondrial gene expression is sensitive to environmental perturbations, consistent with mitochondrial gene expression regulatory pathways being potential antiparasitic targets. Trypanosoma cruzi parasites causing Chagas disease are passed between mammals by the triatomine bug vector. Within the insect, T. cruzi epimastigote-stage cells replicate and progress through the increasingly nutrient-restricted digestive tract, differentiating into infectious, nonreplicative metacyclic trypomastigotes. Thus, we evaluated how nutrient perturbations or metacyclogenesis affects mitochondrial gene expression in different insect life cycle stages. We compared mitochondrial RNA abundances in cultures containing fed, replicating epimastigotes, differentiating cultures containing both starved epimastigotes and metacyclic trypomastigotes and epimastigote starvation cultures. We observed increases in mitochondrial rRNAs and some mRNAs in differentiating cultures. These increases predominated only for the edited CYb mRNA in cultures enriched for metacyclic trypomastigotes. For the other transcripts, abundance increases were linked to starvation and were strongest in culture fractions with a high population of starved epimastigotes. We show that loss of both glucose and amino acids results in rapid increases in RNA abundances that are quickly reduced when these nutrients are returned. Furthermore, the individual RNAs exhibit distinct temporal abundance patterns, suggestive of multiple mechanisms regulating individual transcript abundance. Finally, increases in mitochondrial respiratory complex subunit mRNA abundances were not matched by increases in abundances of nucleus-encoded subunit mRNAs, nor were there statistically significant increases in protein levels of three nucleus-encoded subunits tested. These results show that, similarly to that in T. brucei, the mitochondrial genome in T. cruzi has the potential to alter gene expression in response to environmental or developmental stimuli but for an as-yet-unknown purpose. IMPORTANCE Chagas disease is caused by insect-transmitted Trypanosoma cruzi. Halting T. cruzi’s life cycle in one of its various human and insect life stages would effectively stop the parasite’s infection cycle. T. cruzi is exposed to a variety of environmental conditions in its different life stages, and gene expression must be remodeled to survive these changes. In this work, we look at the impact that one of these changes, nutrient depletion, has on the expression of the 20 gene products encoded in the mitochondrial genome that is neglected by whole-genome studies. We show increases in mitochondrial RNA abundances in starved insect-stage cells, under two conditions in which transition to the infectious stage occurs or does not. This report is the first to show that T. cruzi mitochondrial gene expression is sensitive to environmental perturbations, consistent with mitochondrial gene expression regulatory pathways being potential antiparasitic targets.
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Gimenez AM, Gesumaría MC, Schoijet AC, Alonso GD, Flawiá MM, Racagni GE, Machado EE. Phosphatidylinositol kinase activities in Trypanosoma cruzi epimastigotes. Mol Biochem Parasitol 2015; 203:14-24. [DOI: 10.1016/j.molbiopara.2015.10.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Revised: 10/09/2015] [Accepted: 10/13/2015] [Indexed: 12/28/2022]
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Osmosensing and osmoregulation in unicellular eukaryotes. World J Microbiol Biotechnol 2015; 31:435-43. [DOI: 10.1007/s11274-015-1811-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Accepted: 01/27/2015] [Indexed: 10/24/2022]
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Colchicine treatment reversibly blocks cytokinesis but not mitosis in Trypanosoma cruzi epimastigotes. Parasitol Res 2014; 114:641-9. [DOI: 10.1007/s00436-014-4227-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Accepted: 11/06/2014] [Indexed: 01/13/2023]
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