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Denecke S, Malfara MF, Hodges KR, Holmes NA, Williams AR, Gallagher-Teske JH, Pascarella JM, Daniels AM, Sterk GJ, Leurs R, Ruthel G, Hoang R, Povelones ML, Povelones M. Adhesion of Crithidia fasciculata promotes a rapid change in developmental fate driven by cAMP signaling. mSphere 2024:e0061724. [PMID: 39315810 DOI: 10.1128/msphere.00617-24] [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: 07/17/2024] [Accepted: 09/05/2024] [Indexed: 09/25/2024] Open
Abstract
Trypanosomatids are single-celled parasites responsible for human and animal disease. Typically, colonization of an insect host is required for transmission. Stable attachment of parasites to insect tissues via their single flagellum coincides with differentiation and morphological changes. Although attachment is a conserved stage in trypanosomatid life cycles, the molecular mechanisms are not well understood. To study this process, we elaborate upon an in vitro model in which the swimming form of the trypanosomatid Crithidia fasciculata rapidly differentiates following adhesion to artificial substrates. Live imaging of cells transitioning from swimming to attached shows parasites undergoing a defined sequence of events, including an initial adhesion near the base of the flagellum immediately followed by flagellar shortening, cell rounding, and the formation of a hemidesmosome-like attachment plaque between the tip of the shortened flagellum and the substrate. Quantitative proteomics of swimming versus attached parasites suggests differential regulation of cyclic adenosine monophosphate (cAMP)-based signaling proteins. We have localized two of these proteins to the flagellum of swimming C. fasciculata; however, both are absent from the shortened flagellum of attached cells. Pharmacological inhibition of cAMP phosphodiesterases increased cAMP levels in the cell and prevented attachment. Further, treatment with inhibitor did not affect the growth rate of either swimming or established attached cells, indicating that its effect is limited to a critical window during the early stages of adhesion. These data suggest that cAMP signaling is required for attachment of C. fasciculata and that flagellar signaling domains may be reorganized during differentiation and attachment.IMPORTANCETrypanosomatid parasites cause significant disease burden worldwide and require insect vectors for transmission. In the insect, parasites attach to tissues, sometimes dividing as attached cells or producing motile, infectious forms. The significance and cellular mechanisms of attachment are relatively unexplored. Here, we exploit a model trypanosomatid that attaches robustly to artificial surfaces to better understand this process. This attachment recapitulates that observed in vivo and can be used to define the stages and morphological features of attachment as well as conditions that impact attachment efficiency. We have identified proteins that are enriched in either swimming or attached parasites, supporting a role for the cyclic AMP signaling pathway in the transition from swimming to attached. As this pathway has already been implicated in environmental sensing and developmental transitions in trypanosomatids, our data provide new insights into activities required for parasite survival in their insect hosts.
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Affiliation(s)
- Shane Denecke
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Madeline F Malfara
- Department of Biology, Villanova University, Villanova, Pennsylvania, USA
| | - Kelly R Hodges
- Department of Biology, Villanova University, Villanova, Pennsylvania, USA
| | - Nikki A Holmes
- Department of Biology, Villanova University, Villanova, Pennsylvania, USA
| | - Andre R Williams
- Department of Biology, Villanova University, Villanova, Pennsylvania, USA
| | | | | | - Abigail M Daniels
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Geert Jan Sterk
- Division of Medicinal Chemistry, Amsterdam Institute for Molecules, Medicines and Systems, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan HZ, Amsterdam, the Netherlands
| | - Rob Leurs
- Division of Medicinal Chemistry, Amsterdam Institute for Molecules, Medicines and Systems, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan HZ, Amsterdam, the Netherlands
| | - Gordon Ruthel
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Rachel Hoang
- Department of Biology, Haverford College, Haverford, Pennsylvania, USA
| | - Megan L Povelones
- Department of Biology, Villanova University, Villanova, Pennsylvania, USA
| | - Michael Povelones
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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Ferreira AZL, de Araújo CN, Cardoso ICC, de Souza Mangabeira KS, Rocha AP, Charneau S, Santana JM, Motta FN, Bastos IMD. Metacyclogenesis as the Starting Point of Chagas Disease. Int J Mol Sci 2023; 25:117. [PMID: 38203289 PMCID: PMC10778605 DOI: 10.3390/ijms25010117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Revised: 11/23/2023] [Accepted: 11/26/2023] [Indexed: 01/12/2024] Open
Abstract
Chagas disease is a neglected infectious disease caused by the protozoan Trypanosoma cruzi, primarily transmitted by triatomine vectors, and it threatens approximately seventy-five million people worldwide. This parasite undergoes a complex life cycle, transitioning between hosts and shifting from extracellular to intracellular stages. To ensure its survival in these diverse environments, T. cruzi undergoes extreme morphological and molecular changes. The metacyclic trypomastigote (MT) form, which arises from the metacyclogenesis (MTG) process in the triatomine hindgut, serves as a crucial link between the insect and human hosts and can be considered the starting point of Chagas disease. This review provides an overview of the current knowledge regarding the parasite's life cycle, molecular pathways, and mechanisms involved in metabolic and morphological adaptations during MTG, enabling the MT to evade the immune system and successfully infect human cells.
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Affiliation(s)
| | - Carla Nunes de Araújo
- Pathogen-Host Interface Laboratory, Department of Cell Biology, University of Brasilia, Brasilia 70910-900, Brazil
- Faculty of Ceilândia, University of Brasilia, Brasilia 70910-900, Brazil
| | - Isabela Cunha Costa Cardoso
- Pathogen-Host Interface Laboratory, Department of Cell Biology, University of Brasilia, Brasilia 70910-900, Brazil
| | | | - Amanda Pereira Rocha
- Pathogen-Host Interface Laboratory, Department of Cell Biology, University of Brasilia, Brasilia 70910-900, Brazil
| | - Sébastien Charneau
- Laboratory of Protein Chemistry and Biochemistry, Department of Cell Biology, University of Brasilia, Brasilia 70910-900, Brazil
| | - Jaime Martins Santana
- Pathogen-Host Interface Laboratory, Department of Cell Biology, University of Brasilia, Brasilia 70910-900, Brazil
| | - Flávia Nader Motta
- Pathogen-Host Interface Laboratory, Department of Cell Biology, University of Brasilia, Brasilia 70910-900, Brazil
- Faculty of Ceilândia, University of Brasilia, Brasilia 70910-900, Brazil
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Povelones ML, Holmes NA, Povelones M. A sticky situation: When trypanosomatids attach to insect tissues. PLoS Pathog 2023; 19:e1011854. [PMID: 38128049 PMCID: PMC10734937 DOI: 10.1371/journal.ppat.1011854] [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] [Indexed: 12/23/2023] Open
Abstract
Transmission of trypanosomatids to their mammalian hosts requires a complex series of developmental transitions in their insect vectors, including stable attachment to an insect tissue. While there are many ultrastructural descriptions of attached cells, we know little about the signaling events and molecular mechanisms involved in this process. Each trypanosomatid species attaches to a specific tissue in the insect at a particular stage of its life cycle. Attachment is mediated by the flagellum, which is modified to accommodate a filament-rich plaque within an expanded region of the flagellar membrane. Attachment immediately precedes differentiation to the mammal-infectious stage and in some cases a direct mechanistic link has been demonstrated. In this review, we summarize the current state of knowledge of trypanosomatid attachment in insects, including structure, function, signaling, candidate molecules, and changes in gene expression. We also highlight remaining questions about this process and how the field is poised to address them through modern approaches.
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Affiliation(s)
- Megan L. Povelones
- Department of Biology, Villanova University, Villanova, Pennsylvania, United States of America
| | - Nikki A. Holmes
- Department of Biology, Villanova University, Villanova, Pennsylvania, United States of America
| | - Michael Povelones
- Department of Pathobiology, University of Pennsylvania School of Veterinary Medicine, Philadelphia, Pennsylvania, United States of America
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4
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Chiurillo MA, Carlson J, Bertolini MS, Raja A, Lander N. Dual localization of receptor-type adenylate cyclases and cAMP response protein 3 unveils the presence of two putative signaling microdomains in Trypanosoma cruzi. mBio 2023; 14:e0106423. [PMID: 37477489 PMCID: PMC10470820 DOI: 10.1128/mbio.01064-23] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Accepted: 06/02/2023] [Indexed: 07/22/2023] Open
Abstract
Trypanosoma cruzi is the etiologic agent of Chagas disease, a leading cause of disability and premature death in the Americas. This parasite spends its life between a triatomine insect and a mammalian host, transitioning between developmental stages in response to microenvironmental changes. Among the second messengers driving differentiation in T. cruzi, cAMP has been shown to mediate metacyclogenesis and response to osmotic stress, but this signaling pathway remains largely unexplored in this parasite. Adenylate cyclases (ACs) catalyze the conversion of ATP to cAMP. They comprise a multigene family encoding putative receptor-type ACs in T. cruzi. Using protein sequence alignment, we classified them into five groups and chose a representative member from each group to study their localization (TcAC1-TcAC5). We expressed an HA-tagged version of each protein in T. cruzi and performed immunofluorescence analysis. A peculiar dual localization of TcAC1 and TcAC2 was observed in the flagellar distal domain and in the contractile vacuole complex (CVC), and their enzymatic activity was confirmed by gene complementation in yeast. Furthermore, TcAC1 overexpressing parasites showed an increased metacyclogenesis, a defect in host cell invasion, and a reduced intracellular replication, highlighting the importance of this protein throughout T. cruzi life cycle. These mutants were more tolerant to hypoosmotic stress and showed a higher adhesion capacity during in vitro metacyclogenesis, whereas the wild-type phenotype was restored after disrupting TcAC1 localization. Finally, TcAC1 was found to interact with cAMP response protein 3 (TcCARP3), co-localizing with this protein in the flagellar tip and CVC. IMPORTANCE We identified three components of the cAMP signaling pathway (TcAC1, TcAC2, and TcCARP3) with dual localization in Trypanosoma cruzi: the flagellar distal domain and the CVC, structures involved in cell adhesion and osmoregulation, respectively. We found evidence on the role of TcAC1 in both cellular processes, as well as in metacyclogenesis. Our data suggest that TcACs act as signal sensors and transducers through cAMP synthesis in membrane microdomains. We propose a model in which TcACs sense the harsh conditions in the triatomine hindgut (nutrient deprivation, acidic pH, osmotic stress, ionic composition, hydrophobic interactions) and become active. Synthesis of cAMP then triggers cell adhesion prior completion of metacyclogenesis, while mediating a response to osmotic stress in the parasite. These results shed light into the mechanisms driving cAMP-mediated cell differentiation in T. cruzi, while raising new questions on the activation of TcACs and the role of downstream components of this pathway.
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Affiliation(s)
- Miguel A. Chiurillo
- Department of Biological Sciences, University of Cincinnati, Cincinnati, Ohio, USA
| | - Joshua Carlson
- Department of Biological Sciences, University of Cincinnati, Cincinnati, Ohio, USA
| | - Mayara S. Bertolini
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA
- Department of Cellular Biology, University of Georgia, Athens, Georgia, USA
| | - Aqsa Raja
- Department of Biological Sciences, University of Cincinnati, Cincinnati, Ohio, USA
| | - Noelia Lander
- Department of Biological Sciences, University of Cincinnati, Cincinnati, Ohio, USA
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Chiurillo MA, Ahmed M, González C, Raja A, Lander N. Gene editing of putative cAMP and Ca 2+ -regulated proteins using an efficient cloning-free CRISPR/Cas9 system in Trypanosoma cruzi. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.09.548290. [PMID: 37502958 PMCID: PMC10369910 DOI: 10.1101/2023.07.09.548290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
Trypanosoma cruzi , the agent of Chagas disease, must adapt to a diversity of environmental conditions that it faces during its life cycle. The adaptation to these changes is mediated by signaling pathways that coordinate the cellular responses to the new environmental settings. Cyclic AMP (cAMP) and Calcium (Ca 2+ ) signaling pathways regulate critical cellular processes in this parasite, such as differentiation, osmoregulation, host cell invasion and cell bioenergetics. Although the use of CRISPR/Cas9 technology prompted reverse genetics approaches for functional analysis in T. cruzi , it is still necessary to expand the toolbox for genome editing in this parasite, as for example to perform multigene analysis. Here we used an efficient T7RNAP/Cas9 strategy to tag and delete three genes predicted to be involved in cAMP and Ca 2+ signaling pathways: a putative Ca 2+ /calmodulin-dependent protein kinase ( CAMK ), Flagellar Member 6 ( FLAM6 ) and Cyclic nucleotide-binding domain/C2 domain-containing protein ( CC2CP ). We endogenously tagged these three genes and determined the subcellular localization of the tagged proteins. Furthermore, the strategy used to knockout these genes allow us to presume that TcCC2CP is an essential gene in T. cruzi epimastigotes. Our results will open new venues for future research on the role of these proteins in T. cruzi .
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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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Díaz E, Febres A, Giammarresi M, Silva A, Vanegas O, Gomes C, Ponte-Sucre A. G Protein-Coupled Receptors as Potential Intercellular Communication Mediators in Trypanosomatidae. Front Cell Infect Microbiol 2022; 12:812848. [PMID: 35651757 PMCID: PMC9149261 DOI: 10.3389/fcimb.2022.812848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Accepted: 04/13/2022] [Indexed: 11/13/2022] Open
Abstract
Detection and transduction of environmental signals, constitute a prerequisite for successful parasite invasion; i.e., Leishmania transmission, survival, pathogenesis and disease manifestation and dissemination, with diverse molecules functioning as inter-cellular signaling ligands. Receptors [i.e., G protein-coupled receptors (GPCRs)] and their associated transduction mechanisms, well conserved through evolution, specialize in this function. However, canonical GPCR-related signal transduction systems have not been described in Leishmania, although orthologs, with reduced domains and function, have been identified in Trypanosomatidae. These inter-cellular communication means seem to be essential for multicellular and unicellular organism’s survival. GPCRs are flexible in their molecular architecture and may interact with the so-called receptor activity-modifying proteins (RAMPs), which modulate their function, changing GPCRs pharmacology, acting as chaperones and regulating signaling and/or trafficking in a receptor-dependent manner. In the skin, vasoactive- and neuro- peptides released in response to the noxious stimuli represented by the insect bite may trigger parasite physiological responses, for example, chemotaxis. For instance, in Leishmania (V.) braziliensis, sensory [Substance P, SP, chemoattractant] and autonomic [Vasoactive Intestinal Peptide, VIP, and Neuropeptide Y, NPY, chemorepellent] neuropeptides at physiological levels stimulate in vitro effects on parasite taxis. VIP and NPY chemotactic effects are impaired by their corresponding receptor antagonists, suggesting that the stimulated responses might be mediated by putative GPCRs (with essential conserved receptor domains); the effect of SP is blocked by [(D-Pro 2, D-Trp7,9]-Substance P (10-6 M)] suggesting that it might be mediated by neurokinin-1 transmembrane receptors. Additionally, vasoactive molecules like Calcitonin Gene-Related Peptide [CGRP] and Adrenomedullin [AM], exert a chemorepellent effect and increase the expression of a 24 kDa band recognized in western blot analysis by (human-)-RAMP-2 antibodies. In-silico search oriented towards GPCRs-like receptors and signaling cascades detected a RAMP-2-aligned sequence corresponding to Leishmania folylpolyglutamate synthase and a RAMP-3 aligned protein, a hypothetical Leishmania protein with yet unknown function, suggesting that in Leishmania, CGRP and AM activities may be modulated by RAMP- (-2) and (-3) homologs. The possible presence of proteins and molecules potentially involved in GPCRs cascades, i.e., RAMPs, signpost conservation of ancient signaling systems associated with responses, fundamental for cell survival, (i.e., taxis and migration) and may constitute an open field for description of pharmacophores against Leishmania parasites.
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Affiliation(s)
- Emilia Díaz
- Laboratory of Molecular Physiology, Institute of Experimental Medicine, School of Medicine Luis Razetti, Faculty of Medicine, Universidad Central de Venezuela, Caracas, Venezuela
| | - Anthony Febres
- Section of Infectious Diseases, Baylor College of Medicine, TX, United States
| | - Michelle Giammarresi
- Laboratory of Molecular Physiology, Institute of Experimental Medicine, School of Medicine Luis Razetti, Faculty of Medicine, Universidad Central de Venezuela, Caracas, Venezuela
| | - Adrian Silva
- Laboratory of Molecular Physiology, Institute of Experimental Medicine, School of Medicine Luis Razetti, Faculty of Medicine, Universidad Central de Venezuela, Caracas, Venezuela
| | - Oriana Vanegas
- Pediatric Gastroenterology, University of Iowa, Iowa City, IA, United States
| | - Carlos Gomes
- Royal Berkshire NHS, Foundation Trust, Light House Lab, Bracknell, United Kingdom
| | - Alicia Ponte-Sucre
- Laboratory of Molecular Physiology, Institute of Experimental Medicine, School of Medicine Luis Razetti, Faculty of Medicine, Universidad Central de Venezuela, Caracas, Venezuela
- Medical Mission Institute, Würzburg, Germany
- *Correspondence: Alicia Ponte-Sucre,
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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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Lander N, Chiurillo MA, Docampo R. Signaling pathways involved in environmental sensing in Trypanosoma cruzi. Mol Microbiol 2021; 115:819-828. [PMID: 33034088 PMCID: PMC8032824 DOI: 10.1111/mmi.14621] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Revised: 09/28/2020] [Accepted: 09/30/2020] [Indexed: 12/18/2022]
Abstract
Trypanosoma cruzi is a unicellular parasite and the etiologic agent of Chagas disease. The parasite has a digenetic life cycle alternating between mammalian and insect hosts, where it faces a variety of environmental conditions to which it must adapt in order to survive. The adaptation to these changes is mediated by signaling pathways that coordinate the cellular responses to the new environmental settings. Major environmental changes include temperature, nutrient availability, ionic composition, pH, osmolarity, oxidative stress, contact with host cells and tissues, host immune response, and intracellular life. Some of the signaling pathways and second messengers potentially involved in the response to these changes have been elucidated in recent years and will be the subject of this review.
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Affiliation(s)
- Noelia Lander
- Center for Tropical and Emerging Global Diseases, and Department of Cellular Biology, University of Georgia, Athens, GA, 30602, USA
| | - Miguel A. Chiurillo
- Center for Tropical and Emerging Global Diseases, and Department of Cellular Biology, University of Georgia, Athens, GA, 30602, USA
| | - Roberto Docampo
- Center for Tropical and Emerging Global Diseases, and Department of Cellular Biology, University of Georgia, Athens, GA, 30602, USA
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de Lima LP, Poubel SB, Yuan ZF, Rosón JN, Vitorino FNDL, Holetz FB, Garcia BA, da Cunha JPC. Improvements on the quantitative analysis of Trypanosoma cruzi histone post translational modifications: Study of changes in epigenetic marks through the parasite's metacyclogenesis and life cycle. J Proteomics 2020; 225:103847. [PMID: 32480077 DOI: 10.1016/j.jprot.2020.103847] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 04/26/2020] [Accepted: 05/24/2020] [Indexed: 02/06/2023]
Abstract
Trypanosome histone N-terminal sequences are very divergent from the other eukaryotes, although they are still decorated by post-translational modifications (PTMs). Here, we used a highly robust workflow to analyze histone PTMs in the parasite Trypanosoma cruzi using mass spectrometry-based (MS-based) data-independent acquisition (DIA). We adapted the workflow for the analysis of the parasite's histone sequences by modifying the software EpiProfile 2.0, improving peptide and PTM quantification accuracy. This workflow could now be applied to the study of 141 T. cruzi modified histone peptides, which we used to investigate the dynamics of histone PTMs along the metacyclogenesis and the life cycle of T. cruzi. Global levels of histone acetylation and methylation fluctuates along metacyclogenesis, however most critical differences were observed between parasite life forms. More than 66 histone PTM changes were detected. Strikingly, the histone PTM pattern of metacyclic trypomastigotes is more similar to epimastigotes than to cellular trypomastigotes. Finally, we highlighted changes at the H4 N-terminus and at H3K76 discussing their impact on the trypanosome biology. Altogether, we have optimized a workflow easily applicable to the analysis of histone PTMs in T. cruzi and generated a dataset that may shed lights on the role of chromatin modifications in this parasite. SIGNIFICANCE: Trypanosomes are unicellular parasites that have divergent histone sequences, no chromosome condensation and a peculiar genome/gene regulation. Genes are transcribed from divergent polycistronic regions and post-transcriptional gene regulation play major role on the establishment of transcripts and protein levels. In this regard, the fact that their histones are decorated with multiple PTMs raises interesting questions about their role. Besides, this digenetic organism must adapt to different environments changing its metabolism accordingly. As metabolism and epigenetics are closely related, the study of histone PTMs in trypanosomes may enlighten this strikingly, and not yet fully understood, interplay. From a biomedical perspective, the comprehensive study of molecular mechanisms associated to the metacyclogenesis process is essential to create better strategies for controlling Chagas disease.
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Affiliation(s)
- Loyze P de Lima
- Laboratório de Ciclo Celular, Instituto Butantan, São Paulo, SP, Brazil; Center of Toxins, Immune Response and Cell Signaling (CeTICS), Instituto Butantan, São Paulo, SP, Brazil
| | - Saloe Bispo Poubel
- Laboratório de Ciclo Celular, Instituto Butantan, São Paulo, SP, Brazil; Center of Toxins, Immune Response and Cell Signaling (CeTICS), Instituto Butantan, São Paulo, SP, Brazil; Instituto Carlos Chagas, FIOCRUZ, Rua Algacyr Munhoz Mader, 3775. CIC, Curitiba, PR 81350-010, Brazil
| | - Zuo-Fei Yuan
- Epigenetics Institute, Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Juliana Nunes Rosón
- Laboratório de Ciclo Celular, Instituto Butantan, São Paulo, SP, Brazil; Center of Toxins, Immune Response and Cell Signaling (CeTICS), Instituto Butantan, São Paulo, SP, Brazil
| | - Francisca Nathalia de Luna Vitorino
- Laboratório de Ciclo Celular, Instituto Butantan, São Paulo, SP, Brazil; Center of Toxins, Immune Response and Cell Signaling (CeTICS), Instituto Butantan, São Paulo, SP, Brazil
| | - Fabiola Barbieri Holetz
- Instituto Carlos Chagas, FIOCRUZ, Rua Algacyr Munhoz Mader, 3775. CIC, Curitiba, PR 81350-010, Brazil
| | - Benjamin A Garcia
- Epigenetics Institute, Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Julia Pinheiro Chagas da Cunha
- Laboratório de Ciclo Celular, Instituto Butantan, São Paulo, SP, Brazil; Center of Toxins, Immune Response and Cell Signaling (CeTICS), Instituto Butantan, São Paulo, SP, Brazil.
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11
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Sternlieb T, Schoijet AC, Alonso GD. Intracellular cyclic AMP levels modulate differential adaptive responses on epimastigotes and cell culture trypomastigotes of Trypanosoma cruzi. Acta Trop 2020; 202:105273. [PMID: 31734265 DOI: 10.1016/j.actatropica.2019.105273] [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] [Received: 06/26/2019] [Revised: 11/05/2019] [Accepted: 11/13/2019] [Indexed: 12/20/2022]
Abstract
Among the many environmental challenges the parasite Trypanosoma cruzi has to overcome to complete its life cycle through different hosts, oxidative stress plays a central role. Different stages of this parasite encounter distinct sources of oxidative stress, such as the oxidative burst of the immune system, or the Heme released from hemoglobin degradation in the triatomine's midgut. Also, the redox status of the surroundings functions as a signal to the parasite, triggering processes coupled to differentiation or proliferation. Intracellular second messengers, like cAMP, are responsible for the transduction of environmental queues and initiating cellular processes accordingly. In trypanosomatids cAMP is involved in a variety of processes, including proliferation, differentiation, osmoregulation and quorum sensing. Trypanosomatid phosphodiesterases (PDE) show atypical pharmacological properties and some have been involved in key processes for the survival of the parasites, which validates them as attractive therapeutic targets. Our work here shows that cAMP modulates different processes according to parasite stage. Epimastigotes become more resistant to oxidative stress when pre-treated with cAMP analogs, while in trypomastigotes an increase in intracellular cAMP doesn't seem to aid in this response, although it does increase the number of amastigotes obtained 48 h after infection, compared to the control group. Also, we show that TcrPDEA1, a functionally enigmatic phosphodiesterase with very high Km, is involved in the epimastigotes response to oxidative stress.
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Affiliation(s)
- Tamara Sternlieb
- Laboratorio de señalización y mecanismos adaptativos en tripanosomátidos, Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; Vuelta de Obligado 2490 (C1428ADN), Buenos Aires, Argentina
| | - Alejandra C Schoijet
- Laboratorio de señalización y mecanismos adaptativos en tripanosomátidos, Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; Vuelta de Obligado 2490 (C1428ADN), Buenos Aires, Argentina; Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Guillermo D Alonso
- Laboratorio de señalización y mecanismos adaptativos en tripanosomátidos, Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; Vuelta de Obligado 2490 (C1428ADN), Buenos Aires, Argentina; Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina.
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12
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Lucena ACR, Amorim JC, de Paula Lima CV, Batista M, Krieger MA, de Godoy LMF, Marchini FK. Quantitative phosphoproteome and proteome analyses emphasize the influence of phosphorylation events during the nutritional stress of Trypanosoma cruzi: the initial moments of in vitro metacyclogenesis. Cell Stress Chaperones 2019; 24:927-936. [PMID: 31368045 PMCID: PMC6717228 DOI: 10.1007/s12192-019-01018-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 05/15/2019] [Accepted: 06/14/2019] [Indexed: 12/16/2022] Open
Abstract
Phosphorylation is an important event in cell signaling that is modulated by kinases and phosphatases. In Trypanosoma cruzi, the etiological agent of Chagas disease, approximately 2% of the protein-coding genes encode for protein kinases. This parasite has a heteroxenic life cycle with four different development stages. In the midgut of invertebrate vector, epimastigotes differentiate into metacyclic trypomastigotes in a process known as metacyclogenesis. This process can be reproduced in vitro by submitting parasites to nutritional stress (NS). Aiming to contribute to the elucidation of mechanisms that trigger metacyclogenesis, we applied super-SILAC (super-stable isotope labeling by amino acids in cell culture) and LC-MS/MS to analyze different points during NS. This analysis resulted in the identification of 4205 protein groups and 3643 phosphopeptides with the location of 4846 phosphorylation sites. Several phosphosites were considered modulated along NS and are present in proteins associated with various functions, such as fatty acid synthesis and the regulation of protein expression, reinforcing the importance of phosphorylation and signaling events to the parasite. These modulated sites may be triggers of metacyclogenesis.
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Affiliation(s)
- Aline Castro Rodrigues Lucena
- Laboratory of Applied Science and Technologies in Health, Carlos Chagas Institute, Fiocruz, Curitiba, Parana, Brazil
| | - Juliana Carolina Amorim
- Laboratory of Applied Science and Technologies in Health, Carlos Chagas Institute, Fiocruz, Curitiba, Parana, Brazil
| | - Carla Vanessa de Paula Lima
- Laboratory of Applied Science and Technologies in Health, Carlos Chagas Institute, Fiocruz, Curitiba, Parana, Brazil
| | - Michel Batista
- Laboratory of Applied Science and Technologies in Health, Carlos Chagas Institute, Fiocruz, Curitiba, Parana, Brazil
- Mass Spectrometry Facility RPT02H, Carlos Chagas Institute, Fiocruz, Curitiba, Parana, Brazil
| | - Marco Aurelio Krieger
- Laboratory of Applied Science and Technologies in Health, Carlos Chagas Institute, Fiocruz, Curitiba, Parana, Brazil
| | - Lyris Martins Franco de Godoy
- Laboratory of Applied Science and Technologies in Health, Carlos Chagas Institute, Fiocruz, Curitiba, Parana, Brazil
| | - Fabricio Klerynton Marchini
- Laboratory of Applied Science and Technologies in Health, Carlos Chagas Institute, Fiocruz, Curitiba, Parana, Brazil.
- Mass Spectrometry Facility RPT02H, Carlos Chagas Institute, Fiocruz, Curitiba, Parana, Brazil.
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13
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Discovery of novel Schistosoma mansoni PDE4A inhibitors as potential agents against schistosomiasis. Future Med Chem 2019; 11:1703-1720. [PMID: 31370708 DOI: 10.4155/fmc-2018-0592] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Aim: Due to the urgent need for effective drugs to treat schistosomiasis that act through a known molecular mechanism of action, we focused on a target-based approach with the aim to discover inhibitors of a cyclic nucleotide phosphodiesterase from Schistosoma mansoni (SmPDE4A). Materials & methods: To discover new inhibitors of SmPDE4A homology models of the enzyme structure were constructed based on known human and protozoan homologs. The best two models were selected for subsequent virtual screening of our in-house chemical library. Results & conclusion: A total of 25 library compounds were selected for experimental confirmation as SmPDE4A inhibitors and after dose-response experiments, three top hits were identified. The results presented validate the virtual screening approach to identify new inhibitors for clinically relevant phosphodiesterases.
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14
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Imidazole Derivatives as Promising Agents for the Treatment of Chagas Disease. Antimicrob Agents Chemother 2019; 63:AAC.02156-18. [PMID: 30670432 DOI: 10.1128/aac.02156-18] [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: 10/14/2018] [Accepted: 01/13/2019] [Indexed: 12/17/2022] Open
Abstract
More than 100 years after being first described, Chagas disease remains endemic in 21 Latin American countries and has spread to other continents. Indeed, this disease, which is caused by the protozoan parasite Trypanosoma cruzi, is no longer just a problem for the American continents but has become a global health threat. Current therapies, i.e., nifurtimox and benznidazole (Bz), are far from being adequate, due to their undesirable effects and their lack of efficacy in the chronic phases of the disease. In this work, we present an in-depth phenotypic evaluation in T. cruzi of a new class of imidazole compounds, which were discovered in a previous phenotypic screen against different trypanosomatids and were designed as potential inhibitors of cAMP phosphodiesterases (PDEs). The confirmation of several activities similar or superior to that of Bz prompted a synthesis program of hit optimization and extended structure-activity relationship aimed at improving drug-like properties such as aqueous solubility, which resulted in additional hits with 50% inhibitory concentration (IC50) values similar to that of Bz. The cellular effects of one representative hit, compound 9, on bloodstream trypomastigotes were further investigated. Transmission electron microscopy revealed cellular changes, after just 2 h of incubation with the IC50 concentration, that were consistent with induced autophagy and osmotic stress, mechanisms previously linked to cAMP signaling. Compound 9 induced highly significant increases in both cellular and medium cAMP levels, confirming that inhibition of T. cruzi PDE(s) is part of its mechanism of action. The potent and selective activity of this imidazole-based PDE inhibitor class against T. cruzi constitutes a successful repurposing of research into inhibitors of mammalian PDEs.
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15
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Bradwell KR, Koparde VN, Matveyev AV, Serrano MG, Alves JMP, Parikh H, Huang B, Lee V, Espinosa-Alvarez O, Ortiz PA, Costa-Martins AG, Teixeira MMG, Buck GA. Genomic comparison of Trypanosoma conorhini and Trypanosoma rangeli to Trypanosoma cruzi strains of high and low virulence. BMC Genomics 2018; 19:770. [PMID: 30355302 PMCID: PMC6201504 DOI: 10.1186/s12864-018-5112-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Accepted: 09/25/2018] [Indexed: 01/09/2023] Open
Abstract
Background Trypanosoma conorhini and Trypanosoma rangeli, like Trypanosoma cruzi, are kinetoplastid protist parasites of mammals displaying divergent hosts, geographic ranges and lifestyles. Largely nonpathogenic T. rangeli and T. conorhini represent clades that are phylogenetically closely related to the T. cruzi and T. cruzi-like taxa and provide insights into the evolution of pathogenicity in those parasites. T. rangeli, like T. cruzi is endemic in many Latin American countries, whereas T. conorhini is tropicopolitan. T. rangeli and T. conorhini are exclusively extracellular, while T. cruzi has an intracellular stage in the mammalian host. Results Here we provide the first comprehensive sequence analysis of T. rangeli AM80 and T. conorhini 025E, and provide a comparison of their genomes to those of T. cruzi G and T. cruzi CL, respectively members of T. cruzi lineages TcI and TcVI. We report de novo assembled genome sequences of the low-virulent T. cruzi G, T. rangeli AM80, and T. conorhini 025E ranging from ~ 21–25 Mbp, with ~ 10,000 to 13,000 genes, and for the highly virulent and hybrid T. cruzi CL we present a ~ 65 Mbp in-house assembled haplotyped genome with ~ 12,500 genes per haplotype. Single copy orthologs of the two T. cruzi strains exhibited ~ 97% amino acid identity, and ~ 78% identity to proteins of T. rangeli or T. conorhini. Proteins of the latter two organisms exhibited ~ 84% identity. T. cruzi CL exhibited the highest heterozygosity. T. rangeli and T. conorhini displayed greater metabolic capabilities for utilization of complex carbohydrates, and contained fewer retrotransposons and multigene family copies, i.e. trans-sialidases, mucins, DGF-1, and MASP, compared to T. cruzi. Conclusions Our analyses of the T. rangeli and T. conorhini genomes closely reflected their phylogenetic proximity to the T. cruzi clade, and were largely consistent with their divergent life cycles. Our results provide a greater context for understanding the life cycles, host range expansion, immunity evasion, and pathogenesis of these trypanosomatids. Electronic supplementary material The online version of this article (10.1186/s12864-018-5112-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Katie R Bradwell
- Center for the Study of Biological Complexity, Virginia Commonwealth University, Richmond, VA, USA.,Present address: Institute for Genome Sciences, University of Maryland, Baltimore, MD, USA
| | - Vishal N Koparde
- Center for the Study of Biological Complexity, Virginia Commonwealth University, Richmond, VA, USA
| | - Andrey V Matveyev
- Center for the Study of Biological Complexity, Virginia Commonwealth University, Richmond, VA, USA.,Department of Microbiology and Immunology, Virginia Commonwealth University, Richmond, VA, USA
| | - Myrna G Serrano
- Center for the Study of Biological Complexity, Virginia Commonwealth University, Richmond, VA, USA.,Department of Microbiology and Immunology, Virginia Commonwealth University, Richmond, VA, USA
| | - João M P Alves
- Department of Parasitology, ICB, University of São Paulo, São Paulo, SP, Brazil
| | - Hardik Parikh
- Center for the Study of Biological Complexity, Virginia Commonwealth University, Richmond, VA, USA.,Department of Microbiology and Immunology, Virginia Commonwealth University, Richmond, VA, USA
| | - Bernice Huang
- Center for the Study of Biological Complexity, Virginia Commonwealth University, Richmond, VA, USA.,Department of Microbiology and Immunology, Virginia Commonwealth University, Richmond, VA, USA
| | - Vladimir Lee
- Center for the Study of Biological Complexity, Virginia Commonwealth University, Richmond, VA, USA
| | | | - Paola A Ortiz
- Department of Parasitology, ICB, University of São Paulo, São Paulo, SP, Brazil
| | | | - Marta M G Teixeira
- Department of Parasitology, ICB, University of São Paulo, São Paulo, SP, Brazil
| | - Gregory A Buck
- Center for the Study of Biological Complexity, Virginia Commonwealth University, Richmond, VA, USA. .,Department of Microbiology and Immunology, Virginia Commonwealth University, Richmond, VA, USA.
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16
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Adenylate Cyclases of Trypanosoma brucei, Environmental Sensors and Controllers of Host Innate Immune Response. Pathogens 2018; 7:pathogens7020048. [PMID: 29693583 PMCID: PMC6027212 DOI: 10.3390/pathogens7020048] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 04/12/2018] [Accepted: 04/20/2018] [Indexed: 12/12/2022] Open
Abstract
Trypanosoma brucei, etiological agent of Sleeping Sickness in Africa, is the prototype of African trypanosomes, protozoan extracellular flagellate parasites transmitted by saliva (Salivaria). In these parasites the molecular controls of the cell cycle and environmental sensing are elaborate and concentrated at the flagellum. Genomic analyses suggest that these parasites appear to differ considerably from the host in signaling mechanisms, with the exception of receptor-type adenylate cyclases (AC) that are topologically similar to receptor-type guanylate cyclase (GC) of higher eukaryotes but control a new class of cAMP targets of unknown function, the cAMP response proteins (CARPs), rather than the classical protein kinase A cAMP effector (PKA). T. brucei possesses a large polymorphic family of ACs, mainly associated with the flagellar membrane, and these are involved in inhibition of the innate immune response of the host prior to the massive release of immunomodulatory factors at the first peak of parasitemia. Recent evidence suggests that in T. brucei several insect-specific AC isoforms are involved in social motility, whereas only a few AC isoforms are involved in cytokinesis control of bloodstream forms, attesting that a complex signaling pathway is required for environmental sensing. In this review, after a general update on cAMP signaling pathway and the multiple roles of cAMP, I summarize the existing knowledge of the mechanisms by which pathogenic microorganisms modulate cAMP levels to escape immune defense.
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17
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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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18
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Amorim JC, Batista M, da Cunha ES, Lucena ACR, Lima CVDP, Sousa K, Krieger MA, Marchini FK. Quantitative proteome and phosphoproteome analyses highlight the adherent population during Trypanosoma cruzi metacyclogenesis. Sci Rep 2017; 7:9899. [PMID: 28852088 PMCID: PMC5574995 DOI: 10.1038/s41598-017-10292-3] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Accepted: 08/02/2017] [Indexed: 11/15/2022] Open
Abstract
Trypanosoma cruzi metacyclogenesis is a natural process that occurs inside the triatomine vector and corresponds to the differentiation of non-infective epimastigotes into infective metacyclic trypomastigotes. The biochemical alterations necessary for the differentiation process have been widely studied with a focus on adhesion and nutritional stress. Here, using a mass spectrometry approach, a large-scale phospho(proteome) study was performed with the aim of understanding the metacyclogenesis processes in a quantitative manner. The results indicate that major modulations in the phospho(proteome) occur under nutritional stress and after 12 and 24 h of adhesion. Significant changes involve key cellular processes, such as translation, oxidative stress, and the metabolism of macromolecules, including proteins, lipids, and carbohydrates. Analysis of the signalling triggered by kinases and phosphatases from 7,336 identified phosphorylation sites demonstrates that 260 of these sites are modulated throughout the differentiation process, and some of these modulated proteins have previously been identified as drug targets in trypanosomiasis treatment. To the best of our knowledge, this study provides the first quantitative results highlighting the modulation of phosphorylation sites during metacyclogenesis and the greater coverage of the proteome to the parasite during this process. The data are available via ProteomeXchange with identifier number PXD006171.
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Affiliation(s)
- Juliana C Amorim
- Functional Genomics Laboratory, Carlos Chagas Institute, Fiocruz, Curitiba, Parana, Brazil
| | - Michel Batista
- Functional Genomics Laboratory, Carlos Chagas Institute, Fiocruz, Curitiba, Parana, Brazil.,Mass Spectrometry Facility - RPT02H, Carlos Chagas Institute, Fiocruz, Curitiba, Parana, Brazil
| | - Elizabeth S da Cunha
- Functional Genomics Laboratory, Carlos Chagas Institute, Fiocruz, Curitiba, Parana, Brazil
| | - Aline C R Lucena
- Functional Genomics Laboratory, Carlos Chagas Institute, Fiocruz, Curitiba, Parana, Brazil
| | - Carla V de Paula Lima
- Functional Genomics Laboratory, Carlos Chagas Institute, Fiocruz, Curitiba, Parana, Brazil
| | - Karla Sousa
- Functional Genomics Laboratory, Carlos Chagas Institute, Fiocruz, Curitiba, Parana, Brazil
| | - Marco A Krieger
- Functional Genomics Laboratory, Carlos Chagas Institute, Fiocruz, Curitiba, Parana, Brazil
| | - Fabricio K Marchini
- Functional Genomics Laboratory, Carlos Chagas Institute, Fiocruz, Curitiba, Parana, Brazil. .,Mass Spectrometry Facility - RPT02H, Carlos Chagas Institute, Fiocruz, Curitiba, Parana, Brazil.
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19
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Li Y, Shah-Simpson S, Okrah K, Belew AT, Choi J, Caradonna KL, Padmanabhan P, Ndegwa DM, Temanni MR, Corrada Bravo H, El-Sayed NM, Burleigh BA. Transcriptome Remodeling in Trypanosoma cruzi and Human Cells during Intracellular Infection. PLoS Pathog 2016; 12:e1005511. [PMID: 27046031 PMCID: PMC4821583 DOI: 10.1371/journal.ppat.1005511] [Citation(s) in RCA: 116] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Accepted: 02/28/2016] [Indexed: 01/22/2023] Open
Abstract
Intracellular colonization and persistent infection by the kinetoplastid protozoan parasite, Trypanosoma cruzi, underlie the pathogenesis of human Chagas disease. To obtain global insights into the T. cruzi infective process, transcriptome dynamics were simultaneously captured in the parasite and host cells in an infection time course of human fibroblasts. Extensive remodeling of the T. cruzi transcriptome was observed during the early establishment of intracellular infection, coincident with a major developmental transition in the parasite. Contrasting this early response, few additional changes in steady state mRNA levels were detected once mature T. cruzi amastigotes were formed. Our findings suggest that transcriptome remodeling is required to establish a modified template to guide developmental transitions in the parasite, whereas homeostatic functions are regulated independently of transcriptomic changes, similar to that reported in related trypanosomatids. Despite complex mechanisms for regulation of phenotypic expression in T. cruzi, transcriptomic signatures derived from distinct developmental stages mirror known or projected characteristics of T. cruzi biology. Focusing on energy metabolism, we were able to validate predictions forecast in the mRNA expression profiles. We demonstrate measurable differences in the bioenergetic properties of the different mammalian-infective stages of T. cruzi and present additional findings that underscore the importance of mitochondrial electron transport in T. cruzi amastigote growth and survival. Consequences of T. cruzi colonization for the host include dynamic expression of immune response genes and cell cycle regulators with upregulation of host cholesterol and lipid synthesis pathways, which may serve to fuel intracellular T. cruzi growth. Thus, in addition to the biological inferences gained from gene ontology and functional enrichment analysis of differentially expressed genes in parasite and host, our comprehensive, high resolution transcriptomic dataset provides a substantially more detailed interpretation of T. cruzi infection biology and offers a basis for future drug and vaccine discovery efforts. In-depth knowledge of the functional processes governing host colonization and transmission of pathogenic microorganisms is essential for the advancement of effective intervention strategies. This study focuses on Trypanosoma cruzi, the vector-borne protozoan parasite responsible for human Chagas disease and the leading cause of infectious myocarditis worldwide. To gain global insights into the biology of this parasite and its interaction with mammalian host cells, we have exploited a deep-sequencing approach to generate comprehensive, high-resolution transcriptomic maps for mammalian-infective stages of T. cruzi with the simultaneous interrogation of the human host cell transcriptome across an infection time course. We demonstrate that the establishment of intracellular T. cruzi infection in mammalian host cells is accompanied by extensive remodeling of the parasite and host cell transcriptomes. Despite the lack of transcriptional control mechanisms in trypanosomatids, our analyses identified functionally-enriched processes within sets of developmentally-regulated transcripts in T. cruzi that align with known or predicted biological features of the parasite. The novel insights into the biology of intracellular T. cruzi infection and the regulation of amastigote development gained in this study establish a unique foundation for functional network analyses that will be instrumental in providing functional links between parasite dependencies and host functional pathways that have the potential to be exploited for intervention.
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Affiliation(s)
- Yuan Li
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland, United States of America
| | - Sheena Shah-Simpson
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, Massachusetts, United States of America
| | - Kwame Okrah
- Center for Bioinformatics and Computational Biology, University of Maryland, College Park, Maryland, United States of America
| | - A Trey Belew
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland, United States of America
| | - Jungmin Choi
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland, United States of America
| | - Kacey L Caradonna
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, Massachusetts, United States of America
| | - Prasad Padmanabhan
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, Massachusetts, United States of America
| | - David M Ndegwa
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, Massachusetts, United States of America
| | - M Ramzi Temanni
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland, United States of America
| | - Héctor Corrada Bravo
- Center for Bioinformatics and Computational Biology, University of Maryland, College Park, Maryland, United States of America
| | - Najib M El-Sayed
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland, United States of America.,Center for Bioinformatics and Computational Biology, University of Maryland, College Park, Maryland, United States of America
| | - Barbara A Burleigh
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, Massachusetts, United States of America
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20
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Tagoe DNA, Kalejaiye TD, de Koning HP. The ever unfolding story of cAMP signaling in trypanosomatids: vive la difference! Front Pharmacol 2015; 6:185. [PMID: 26441645 PMCID: PMC4561360 DOI: 10.3389/fphar.2015.00185] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 08/17/2015] [Indexed: 12/25/2022] Open
Abstract
Kinetoplastids are unicellular, eukaryotic, flagellated protozoans containing the eponymous kinetoplast. Within this order, the family of trypanosomatids are responsible for some of the most serious human diseases, including Chagas disease (Trypanosoma cruzi), sleeping sickness (Trypanosoma brucei spp.), and leishmaniasis (Leishmania spp). Although cAMP is produced during the life cycle stages of these parasites, its signaling pathways are very different from those of mammals. The absence of G-protein-coupled receptors, the presence of structurally different adenylyl cyclases, the paucity of known cAMP effector proteins and the stringent need for regulation of cAMP in the small kinetoplastid cells all suggest a significantly different biochemical pathway and likely cell biology. However, each of the main kinetoplastid parasites express four class 1-type cyclic nucleotide-specific phosphodiesterases (PDEA-D), which have highly similar catalytic domains to that of human PDEs. To date, only TbrPDEB, expressed as two slightly different isoforms TbrPDEB1 and B2, has been found to be essential when ablated. Although the genomes contain reasonably well conserved genes for catalytic and regulatory domains of protein kinase A, these have been shown to have varied structural and functional roles in the different species. Recent discovery of a role of cAMP/AMP metabolism in a quorum-sensing signaling pathway in T. brucei, and the identification of downstream cAMP Response Proteins (CARPs) whose expression levels correlate with sensitivity to PDE inhibitors, suggests a complex signaling cascade. The interplay between the roles of these novel CARPs and the quorum-sensing signaling pathway on cell division and differentiation makes for intriguing cell biology and a new paradigm in cAMP signal transduction, as well as potential targets for trypanosomatid-specific cAMP pathway-based therapeutics.
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Affiliation(s)
- Daniel N A Tagoe
- Wellcome Trust Centre for Molecular Parasitology, University of Glasgow , Glasgow, UK ; Institute of Infection, Inflammation and Immunity, College of Medical, Veterinary and Life Sciences, University of Glasgow , Glasgow, UK ; Department of Laboratory Technology, Division of Medical Laboratory Technology, University of Cape Coast , Cape Coast, Ghana
| | - Titilola D Kalejaiye
- Institute of Infection, Inflammation and Immunity, College of Medical, Veterinary and Life Sciences, University of Glasgow , Glasgow, UK
| | - Harry P de Koning
- Institute of Infection, Inflammation and Immunity, College of Medical, Veterinary and Life Sciences, University of Glasgow , Glasgow, UK
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21
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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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22
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Hashimoto M, Morales J, Uemura H, Mikoshiba K, Nara T. A Novel Method for Inducing Amastigote-To-Trypomastigote Transformation In Vitro in Trypanosoma cruzi Reveals the Importance of Inositol 1,4,5-Trisphosphate Receptor. PLoS One 2015; 10:e0135726. [PMID: 26267656 PMCID: PMC4534300 DOI: 10.1371/journal.pone.0135726] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Accepted: 07/24/2015] [Indexed: 12/04/2022] Open
Abstract
Background Trypanosoma cruzi is a parasitic protist that causes Chagas disease, which is prevalent in Latin America. Because of the unavailability of an effective drug or vaccine, and because about 8 million people are infected with the parasite worldwide, the development of novel drugs demands urgent attention. T. cruzi infects a wide variety of mammalian nucleated cells, with a preference for myocardial cells. Non-dividing trypomastigotes in the bloodstream infect host cells where they are transformed into replication-capable amastigotes. The amastigotes revert to trypomastigotes (trypomastigogenesis) before being shed out of the host cells. Although trypomastigote transformation is an essential process for the parasite, the molecular mechanisms underlying this process have not yet been clarified, mainly because of the lack of an assay system to induce trypomastigogenesis in vitro. Methodology/Principal Findings Cultivation of amastigotes in a transformation medium composed of 80% RPMI-1640 and 20% Grace’s Insect Medium mediated their transformation into trypomastigotes. Grace’s Insect Medium alone also induced trypomastigogenesis. Furthermore, trypomastigogenesis was induced more efficiently in the presence of fetal bovine serum. Trypomastigotes derived from in vitro trypomastigogenesis were able to infect mammalian host cells as efficiently as tissue-culture-derived trypomastigotes (TCT) and expressed a marker protein for TCT. Using this assay system, we demonstrated that T. cruzi inositol 1,4,5-trisphosphate receptor (TcIP3R)—an intracellular Ca2+ channel and a key molecule involved in Ca2+ signaling in the parasite—is important for the transformation process. Conclusion/Significance Our findings provide a new tool to identify the molecular mechanisms of the amastigote-to-trypomastigote transformation, leading to a new strategy for drug development against Chagas disease.
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Affiliation(s)
- Muneaki Hashimoto
- Department of Molecular and Cellular Parasitology, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113–8421, Japan
- * E-mail:
| | - Jorge Morales
- Department of Molecular and Cellular Parasitology, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113–8421, Japan
| | - Haruki Uemura
- Department of Protozoology, Institute of Tropical Medicine, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852–8523, Japan
| | - Katsuhiko Mikoshiba
- Laboratory for Developmental Neurobiology, RIKEN Brain Science Institute, Saitama 351–0198, Japan
- Calcium Oscillation Project, International Cooperative Research Project and Solution-Oriented Research for Science and Technology, Japan Science and Technology Agency, Kawaguchi, Saitama 332–0012, Japan
| | - Takeshi Nara
- Department of Molecular and Cellular Parasitology, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113–8421, Japan
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Hamedi A, Botelho L, Britto C, Fragoso SP, Umaki ACS, Goldenberg S, Bottu G, Salmon D. In vitro metacyclogenesis of Trypanosoma cruzi induced by starvation correlates with a transient adenylyl cyclase stimulation as well as with a constitutive upregulation of adenylyl cyclase expression. Mol Biochem Parasitol 2015; 200:9-18. [PMID: 25912925 DOI: 10.1016/j.molbiopara.2015.04.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2014] [Revised: 04/10/2015] [Accepted: 04/15/2015] [Indexed: 10/23/2022]
Abstract
The Trypanosoma cruzi adenylyl cyclase (AC) multigene family encodes different isoforms (around 15) sharing a variable large N-terminal domain, which is extracellular and receptor-like, followed by a transmembrane helix and a conserved C-terminal catalytic domain. It was proposed that these key enzymes in the cAMP signalling pathway allow the parasite to sense its changing extracellular milieu in order to rapidly adapt to its new environment, which is generally achieved through a differentiation process. One of the critical differentiation events the parasitic protozoan T. cruzi undergoes during its life cycle, known as metacyclogenesis, occurs in the digestive tract of the insect and corresponds to the differentiation from noninfective epimastigotes to infective metacyclic trypomastigote forms. By in vitro monitoring the activity of AC during metacyclogenesis, we showed that both the activity of AC and the intracellular cAMP content follow a similar pattern of transient stimulation in a two-step process, with a first activation peak occurring during the first hours of nutritional stress and a second peak between 6 and 48 h, corresponding to the cellular adhesion. During this differentiation process, a general mechanism of upregulation of AC expression of both mRNA and protein is triggered and in particular for a major subclass of these enzymes that are present in various gene copies commonly associated to the THT gene clusters. Although the scattered genome distribution of these gene copies is rather unusual in trypanosomatids and seems to be a recent acquisition in the evolution of the T. cruzi clade, their encoded product redistributed on the flagellum of the parasite upon differentiation could be important to sense the extracellular milieu.
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Affiliation(s)
- Afsaneh Hamedi
- Fiocruz, Instituto Oswaldo Cruz, Av. Brasil 4365, 21040-900 Rio de Janeiro, RJ, Brazil
| | - Larisse Botelho
- Laboratório de Biologia Molecular e Doenças Endêmicas, Instituto Oswaldo Cruz, Fiocruz, Av. Brasil 4365, 21040-900 Rio de Janeiro, Brazil
| | - Constança Britto
- Laboratório de Biologia Molecular e Doenças Endêmicas, Instituto Oswaldo Cruz, Fiocruz, Av. Brasil 4365, 21040-900 Rio de Janeiro, Brazil
| | - Stenio Perdigão Fragoso
- Instituto de Biologia Molecular do Paraná, Rua Professor Algacyr Munhoz Mader 3775, Curitiba 81350-010, PR, Brazil
| | | | - Samuel Goldenberg
- Instituto de Biologia Molecular do Paraná, Rua Professor Algacyr Munhoz Mader 3775, Curitiba 81350-010, PR, Brazil
| | - Guy Bottu
- Université Libre de Bruxelles, Campus de la Plaine, Boulevard du Triomphe, 1050 Brussels, Belgium
| | - Didier Salmon
- Institute of Medical Biochemistry Leopoldo de Meis, Centro de Ciências e da Saúde, Federal University of Rio de Janeiro, Av. Brigadeiro Trompowsky, Rio de Janeiro 21941-590, Brazil.
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Pereira M, Soares C, Canuto GAB, Tavares MFM, Colli W, Alves MJM. Down regulation of NO signaling in Trypanosoma cruzi upon parasite-extracellular matrix interaction: changes in protein modification by nitrosylation and nitration. PLoS Negl Trop Dis 2015; 9:e0003683. [PMID: 25856423 PMCID: PMC4391712 DOI: 10.1371/journal.pntd.0003683] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2014] [Accepted: 03/06/2015] [Indexed: 01/18/2023] Open
Abstract
Background Adhesion of the Trypanosoma cruzi trypomastigotes, the causative agent of Chagas' disease in humans, to components of the extracellular matrix (ECM) is an important step in host cell invasion. The signaling events triggered in the parasite upon binding to ECM are less explored and, to our knowledge, there is no data available regarding •NO signaling. Methodology/Principal Findings Trypomastigotes were incubated with ECM for different periods of time. Nitrated and S-nitrosylated proteins were analyzed by Western blotting using anti-nitrotyrosine and S-nitrosyl cysteine antibodies. At 2 h incubation time, a decrease in NO synthase activity, •NO, citrulline, arginine and cGMP concentrations, as well as the protein modifications levels have been observed in the parasite. The modified proteins were enriched by immunoprecipitation with anti-nitrotyrosine antibodies (nitrated proteins) or by the biotin switch method (S-nitrosylated proteins) and identified by MS/MS. The presence of both modifications was confirmed in proteins of interest by immunoblotting or immunoprecipitation. Conclusions/Significance For the first time it was shown that T. cruzi proteins are amenable to modifications by S-nitrosylation and nitration. When T. cruzi trypomastigotes are incubated with the extracellular matrix there is a general down regulation of these reactions, including a decrease in both NOS activity and cGMP concentration. Notwithstanding, some specific proteins, such as enolase or histones had, at least, their nitration levels increased. This suggests that post-translational modifications of T. cruzi proteins are not only a reflex of NOS activity, implying other mechanisms that circumvent a relatively low synthesis of •NO. In conclusion, the extracellular matrix, a cell surrounding layer of macromolecules that have to be trespassed by the parasite in order to be internalized into host cells, contributes to the modification of •NO signaling in the parasite, probably an essential move for the ensuing invasion step. Interaction of Trypanosoma cruzi with the extracellular matrix (ECM) is an essential step in the invasion of mammalian cells. However, the nature of the signaling triggered in the parasite is poorly understood. Herein the key role of nitric oxide in T. cruzi signaling is described, using an ECM preparation, in the absence of host cells. Inhibition of NOS activity, with the expected decrease in •NO production, as well as decrease in cGMP concentration were observed by the incubation of T. cruzi trypomastigotes with ECM. Additionally, lower levels of protein S-nitrosylation and nitration were detected. These post-translational modifications have been analyzed by biotin-switch and protein immunoprecipitation approaches coupled to mass spectrometry. The presence of both modifications was confirmed for specific proteins, as mucin II (S-nitrosylation), histones, enolase and tubulins. To our knowledge, decrease in the •NO signaling pathway upon T. cruzi trypomastigotes adhesion to ECM, affecting both the canonical pathway (•NO-soluble guanylyl cyclase-cGMP) and protein S-nitrosylation and nitration is described for the first time in this parasite.
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Affiliation(s)
- Milton Pereira
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
| | - Chrislaine Soares
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
| | | | | | - Walter Colli
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
| | - Maria Julia M. Alves
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
- * E-mail:
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Jäger AV, De Gaudenzi JG, Mild JG, Mc Cormack B, Pantano S, Altschuler DL, Edreira MM. Identification of novel cyclic nucleotide binding proteins in Trypanosoma cruzi. Mol Biochem Parasitol 2015; 198:104-12. [PMID: 25724722 DOI: 10.1016/j.molbiopara.2015.02.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Revised: 02/03/2015] [Accepted: 02/14/2015] [Indexed: 11/19/2022]
Abstract
Cyclic AMP has been implicated as second messenger in a wide range of cellular processes. In the protozoan parasite Trypanosoma cruzi, cAMP is involved in the development of the parasite's life cycle. While cAMP effectors have been widely studied in other eukaryotic cells, little is known about cAMP's mechanism of action in T. cruzi. To date, only a cAMP-dependent protein kinase A (PKA) has been cloned and characterised in this parasite; however experimental evidence indicates the existence of cAMP-dependent, PKA-independent events. In order to identify new cAMP binding proteins as potential cAMP effectors, we carried out in silico studies using the predicted T. cruzi proteome. Using a combination of search methods 27 proteins with putative cNMP binding domains (CBDs) were identified. Phylogenetic analysis of the CBDs presented a homogeneous distribution, with sequences segregated into two main branches: one containing kinases-like proteins and the other gathering hypothetical proteins with different function or no other known. Comparative modelling of the strongest candidates provides support for the hypothesis that these proteins may give rise to structurally viable cyclic nucleotide binding domains. Pull-down and nucleotide displacement assays strongly suggest that TcCLB.508523.80 could bind cAMP and eventually be a new putative PKA-independent cAMP effector in T. cruzi.
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Affiliation(s)
- Adriana V Jäger
- Instituto de Investigaciones Biotecnológicas-Instituto Tecnológico de Chascomús, UNSAM-CONICET, Buenos Aires, Argentina
| | - Javier G De Gaudenzi
- Instituto de Investigaciones Biotecnológicas-Instituto Tecnológico de Chascomús, UNSAM-CONICET, Buenos Aires, Argentina
| | - Jesica G Mild
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad de Buenos Aires, Argentina; IQUIBICEN-CONICET, Ciudad de Buenos Aires, Argentina
| | - Bárbara Mc Cormack
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad de Buenos Aires, Argentina
| | | | - Daniel L Altschuler
- Department of Pharmacology and Chemical Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA.
| | - Martin M Edreira
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad de Buenos Aires, Argentina; IQUIBICEN-CONICET, Ciudad de Buenos Aires, Argentina; Department of Pharmacology and Chemical Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA.
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26
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Queiroz RML, Charneau S, Mandacaru SC, Schwämmle V, Lima BD, Roepstorff P, Ricart CAO. Quantitative proteomic and phosphoproteomic analysis of Trypanosoma cruzi amastigogenesis. Mol Cell Proteomics 2014; 13:3457-72. [PMID: 25225356 DOI: 10.1074/mcp.m114.040329] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Chagas disease is a tropical neglected disease endemic in Latin America caused by the protozoan Trypanosoma cruzi. The parasite has four major life stages: epimastigote, metacyclic trypomastigote, bloodstream trypomastigote, and amastigote. The differentiation from infective trypomastigotes into replicative amastigotes, called amastigogenesis, takes place in vivo inside mammalian host cells after a period of incubation in an acidic phagolysosome. This differentiation process can be mimicked in vitro by incubating tissue-culture-derived trypomastigotes in acidic DMEM. Here we used this well-established differentiation protocol to perform a comprehensive quantitative proteomic and phosphoproteomic analysis of T. cruzi amastigogenesis. Samples from fully differentiated forms and two biologically relevant intermediate time points were Lys-C/trypsin digested, iTRAQ-labeled, and multiplexed. Subsequently, phosphopeptides were enriched using a TiO2 matrix. Non-phosphorylated peptides were fractionated via hydrophilic interaction liquid chromatography prior to LC-MS/MS analysis. LC-MS/MS and bioinformatics procedures were used for protein and phosphopeptide quantitation, identification, and phosphorylation site assignment. We were able to identify regulated proteins and pathways involved in coordinating amastigogenesis. We also observed that a significant proportion of the regulated proteins were membrane proteins. Modulated phosphorylation events coordinated by protein kinases and phosphatases that are part of the signaling cascade induced by incubation in acidic medium were also evinced. To our knowledge, this work is the most comprehensive quantitative proteomics study of T. cruzi amastigogenesis, and these data will serve as a trustworthy basis for future studies, and possibly for new potential drug targets.
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Affiliation(s)
- Rayner M L Queiroz
- From the ‡Department of Cell Biology, Institute of Biology, University of Brasilia, Brasília, 70910-900 Brazil; §Department of Biochemistry and Molecular Biology, University of Southern Denmark, 5230 Odense M, Denmark
| | - Sébastien Charneau
- From the ‡Department of Cell Biology, Institute of Biology, University of Brasilia, Brasília, 70910-900 Brazil
| | - Samuel C Mandacaru
- From the ‡Department of Cell Biology, Institute of Biology, University of Brasilia, Brasília, 70910-900 Brazil
| | - Veit Schwämmle
- §Department of Biochemistry and Molecular Biology, University of Southern Denmark, 5230 Odense M, Denmark
| | - Beatriz D Lima
- From the ‡Department of Cell Biology, Institute of Biology, University of Brasilia, Brasília, 70910-900 Brazil
| | - Peter Roepstorff
- §Department of Biochemistry and Molecular Biology, University of Southern Denmark, 5230 Odense M, Denmark
| | - Carlos A O Ricart
- From the ‡Department of Cell Biology, Institute of Biology, University of Brasilia, Brasília, 70910-900 Brazil;
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Golgi UDP-GlcNAc:polypeptide O-α-N-Acetyl-d-glucosaminyltransferase 2 (TcOGNT2) regulates trypomastigote production and function in Trypanosoma cruzi. EUKARYOTIC CELL 2014; 13:1312-27. [PMID: 25084865 DOI: 10.1128/ec.00165-14] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
All life cycle stages of the protozoan parasite Trypanosoma cruzi are enveloped by mucin-like glycoproteins which, despite major changes in their polypeptide cores, are extensively and similarly O-glycosylated. O-Glycan biosynthesis is initiated by the addition of αGlcNAc to Thr in a reaction catalyzed by Golgi UDP-GlcNAc:polypeptide O-α-N-acetyl-d-glucosaminyltransferases (ppαGlcNAcTs), which are encoded by TcOGNT1 and TcOGNT2. We now directly show that TcOGNT2 is associated with the Golgi apparatus of the epimastigote stage and is markedly downregulated in both differentiated metacyclic trypomastigotes (MCTs) and cell culture-derived trypomastigotes (TCTs). The significance of downregulation was examined by forced continued expression of TcOGNT2, which resulted in a substantial increase of TcOGNT2 protein levels but only modestly increased ppαGlcNAcT activity in extracts and altered cell surface glycosylation in TCTs. Constitutive TcOGNT2 overexpression had no discernible effect on proliferating epimastigotes but negatively affected production of both types of trypomastigotes. MCTs differentiated from epimastigotes at a low frequency, though they were apparently normal based on morphological and biochemical criteria. However, these MCTs exhibited an impaired ability to produce amastigotes and TCTs in cell culture monolayers, most likely due to a reduced infection frequency. Remarkably, inhibition of MCT production did not depend on TcOGNT2 catalytic activity, whereas TCT production was inhibited only by active TcOGNT2. These findings indicate that TcOGNT2 downregulation is important for proper differentiation of MCTs and functioning of TCTs and that TcOGNT2 regulates these functions by using both catalytic and noncatalytic mechanisms.
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Damasceno FS, Barisón MJ, Pral EMF, Paes LS, Silber AM. Memantine, an antagonist of the NMDA glutamate receptor, affects cell proliferation, differentiation and the intracellular cycle and induces apoptosis in Trypanosoma cruzi. PLoS Negl Trop Dis 2014; 8:e2717. [PMID: 24587468 PMCID: PMC3937314 DOI: 10.1371/journal.pntd.0002717] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Accepted: 01/13/2014] [Indexed: 12/15/2022] Open
Abstract
Chagas' disease is caused by the protozoan parasite Trypanosoma cruzi and affects approximately 10 million people in endemic areas of Mexico and Central and South America. Currently available chemotherapies are limited to two compounds: Nifurtimox and Benznidazole. Both drugs reduce the symptoms of the disease and mortality among infected individuals when used during the acute phase, but their efficacy during the chronic phase (during which the majority of cases are diagnosed) remains controversial. Moreover, these drugs have several side effects. The aim of this study was to evaluate the effect of Memantine, an antagonist of the glutamate receptor in the CNS of mammals, on the life cycle of T. cruzi. Memantine exhibited a trypanocidal effect, inhibiting the proliferation of epimastigotes (IC50 172.6 µM). Furthermore, this compound interfered with metacyclogenesis (approximately 30% reduction) and affected the energy metabolism of the parasite. In addition, Memantine triggered mechanisms that led to the apoptosis-like cell death of epimastigotes, with extracellular exposure of phosphatidylserine, increased production of reactive oxygen species, decreased ATP levels, increased intracellular Ca2+ and morphological changes. Moreover, Memantine interfered with the intracellular cycle of the parasite, specifically the amastigote stage (IC50 31 µM). Interestingly, the stages of the parasite life cycle that require more energy (epimastigote and amastigote) were more affected as were the processes of differentiation and cell invasion. Trypanosoma cruzi is a parasite transmitted to mammal hosts by insect vectors known as kissing bugs. This species can result pathogenic for humans, causing Chagas' disease in the Americas. Its treatment relies on two drugs discovered more than 40 years ago. Besides their toxicity, a main drawback of these drugs is the fact that they are highly efficient only during the acute phase of the infection. But due to the lack of specific symptoms, the acute phase of the infection is largely not diagnosed. In fact, most of patients are diagnosed in the chronic phase, where the treatments are not satisfactory. In view of that, it is urgent to look for new drugs with low toxicity and able to kill the parasite in chronic patients. On the basis of previous finding, we looked for drugs against glutamate recognizing surface molecules, keeping special attention on those that are already in use in humans for other purposes (this strategy is called drug repositioning, and allow to save time and money in clinical trials: several parameters such as toxicity, pharmacokinetics, side effects in humans are already known). Here we report that Memantine, a NMDA glutamate receptors antagonist already in use to treat Alzheimer's disease, presents interesting perspectives as a trypanocidal drug.
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Affiliation(s)
- Flávia Silva Damasceno
- Unit for Drug Discovery, Departamento de Parasitologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
| | - María Julia Barisón
- Unit for Drug Discovery, Departamento de Parasitologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
| | - Elisabeth Mieko Furusho Pral
- Unit for Drug Discovery, Departamento de Parasitologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
| | - Lisvane Silva Paes
- Unit for Drug Discovery, Departamento de Parasitologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
| | - Ariel Mariano Silber
- Unit for Drug Discovery, Departamento de Parasitologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
- * E-mail:
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Menna-Barreto RFS, Perales J. The expected outcome of the Trypanosoma cruzi proteomic map: a review of its potential biological applications for drug target discovery. Subcell Biochem 2014; 74:305-322. [PMID: 24264251 DOI: 10.1007/978-94-007-7305-9_13] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Chagas disease is a neglected tropical illness endemic to Latin America, and its treatment remains unsatisfactory. This disease is caused by the hemoflagellate protozoan Trypanosoma cruzi, which has a complex life cycle involving three evolutive forms in both vertebrate and invertebrate hosts. Targeting metabolic pathways in the parasite for rational drug design represents a promising research field. This research area requires high performance techniques and proteomics become a powerful tool in this context. Here, we review advances in the construction of proteomic maps of the different forms of T. cruzi, emphasizing their biological applications towards the identification of alternative candidates for drug intervention.
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Affiliation(s)
- Rubem F S Menna-Barreto
- Laboratório de Biologia Celular, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, RJ, 21040-360, Brazil
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Application of a phosphodiesterase-4 (PDE4) inhibitor to abort chronic toxoplasmosis and to mitigate consequential pathological changes. J Microsc Ultrastruct 2014. [DOI: 10.1016/j.jmau.2014.05.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Bayer-Santos E, Cunha-e-Silva NL, Yoshida N, Franco da Silveira J. Expression and cellular trafficking of GP82 and GP90 glycoproteins during Trypanosoma cruzi metacyclogenesis. Parasit Vectors 2013; 6:127. [PMID: 23634710 PMCID: PMC3652755 DOI: 10.1186/1756-3305-6-127] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Accepted: 04/23/2013] [Indexed: 11/25/2022] Open
Abstract
Background The transformation of noninfective epimastigotes into infective metacyclic trypomastigotes (metacyclogenesis) is a fundamental step in the life cycle of Trypanosoma cruzi, comprising several morphological and biochemical changes. GP82 and GP90 are glycoproteins expressed at the surface of metacyclic trypomastigote, with opposite roles in mammalian cell invasion. GP82 is an adhesin that promotes cell invasion, while GP90 acts as a negative regulator of parasite internalization. Our understanding of the synthesis and intracellular trafficking of GP82 and GP90 during metacyclogenesis is still limited. Therefore, we decided to determine whether GP82 and GP90 are expressed only in fully differentiated metacyclic forms or they start to be expressed in intermediate forms undergoing differentiation. Methods Parasite populations enriched in intermediate forms undergoing differentiation were analyzed by quantitative real-time PCR, Western blot, flow cytometry and immunofluorescence to assess GP82 and GP90 expression. Results We found that GP82 and GP90 mRNAs and proteins are expressed in intermediate forms and reach higher levels in fully differentiated metacyclic forms. Surprisingly, GP82 and GP90 presented distinct cellular localizations in intermediate forms compared to metacyclic trypomastigotes. In intermediate forms, GP82 is localized in organelles at the posterior region and colocalizes with cruzipain, while GP90 is localized at the flagellar pocket region. Conclusions This study discloses new aspects of protein expression and trafficking during T. cruzi differentiation by showing that the machinery involved in GP82 and GP90 gene expression starts to operate early in the differentiation process and that different secretion pathways are responsible for delivering these glycoproteins toward the cell surface.
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Affiliation(s)
- Ethel Bayer-Santos
- Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo, São Paulo, SP 04023-062, Brazil
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de Godoy LMF, Marchini FK, Pavoni DP, Rampazzo RDCP, Probst CM, Goldenberg S, Krieger MA. Quantitative proteomics of Trypanosoma cruzi during metacyclogenesis. Proteomics 2013; 12:2694-703. [PMID: 22761176 DOI: 10.1002/pmic.201200078] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Trypanosoma cruzi is the etiologic agent of Chagas disease, which is estimated to affect over eight million people around the world. Trypanosoma cruzi has a complex life cycle, involving insect and mammalian hosts and four distinct developmental stages: epimastigotes, metacyclic trypomastigotes, amastigotes, and bloodstream trypomastigotes. Metacyclogenesis is the process by which T. cruzi epimastigotes differentiate into metacyclic trypomastigotes and acquire infectivity, and involves differential gene expression associated with acquisition of virulence. In T. cruzi, gene expression regulation is achieved mainly posttranscriptionally. Therefore, proteomics-based approaches are extremely useful for gaining a better understanding of the changes that occur in the stage-regulated gene expression program of the parasite at the molecular level. Here, we performed an in-depth quantitative MS-based proteomic study of T. cruzi metacyclogenesis and quantified almost 3000 proteins expressed during the process of differentiation. To the best of our knowledge, this work is the most comprehensive quantitative proteomics study of different cell populations of T. cruzi available so far. We identified relevant proteins and pathways involved in the parasite's differentiation and infectivity acquisition, opening new perspectives for further studies that could, ultimately, lead to the identification of new targets for chemotherapy.
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McDonough KA, Rodriguez A. The myriad roles of cyclic AMP in microbial pathogens: from signal to sword. Nat Rev Microbiol 2011; 10:27-38. [PMID: 22080930 DOI: 10.1038/nrmicro2688] [Citation(s) in RCA: 212] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
All organisms must sense and respond to their external environments, and this signal transduction often involves second messengers such as cyclic nucleotides. One such nucleotide is cyclic AMP, a universal second messenger that is used by diverse forms of life, including mammals, fungi, protozoa and bacteria. In this review, we discuss the many roles of cAMP in bacterial, fungal and protozoan pathogens and its contributions to microbial pathogenesis. These roles include the coordination of intracellular processes, such as virulence gene expression, with extracellular signals from the environment, and the manipulation of host immunity by increasing cAMP levels in host cells during infection.
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Affiliation(s)
- Kathleen A McDonough
- Wadsworth Center, New York State Department of Health, 120 New Scotland Avenue, PO Box 22002, Albany, New York, New York 12201-2002, USA. kathleen.mcdonough@ wadsworth.org
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Goldenberg S, Ávila AR. Aspects of Trypanosoma cruzi stage differentiation. ADVANCES IN PARASITOLOGY 2011; 75:285-305. [PMID: 21820561 DOI: 10.1016/b978-0-12-385863-4.00013-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Trypanosoma cruzi alternates between different morphological and functional types during its life cycle. Since the discovery of this parasite at the beginning of the twentieth century, efforts have been made to determine the basis of its pathogenesis in the course of Chagas disease and its biochemical constituents. There has also been work to develop tools and strategies for prophylaxis of the important disease caused by these parasites which affects millions of people in Latin America. The identification of axenic conditions allowing T. cruzi growth and differentiation has led to the identification and characterization of stage-specific antigens as well as a better characterization of the biological properties and biochemical particularities of each individual developmental stage. The recent availability of genomic data should pave the way to new progress in our knowledge of the biology and pathogenesis of T. cruzi. This review addresses the differentiation and major stage-specific antigens of T. cruzi and attempts to describe the complexity of the parasite and of the disease it causes.
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Bao Y, Weiss LM, Ma YF, Kahn S, Huang H. Protein kinase A catalytic subunit interacts and phosphorylates members of trans-sialidase super-family in Trypanosoma cruzi. Microbes Infect 2010; 12:716-26. [PMID: 20466066 DOI: 10.1016/j.micinf.2010.04.014] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2010] [Revised: 04/23/2010] [Accepted: 04/29/2010] [Indexed: 12/01/2022]
Abstract
Protein kinase A (PKA) has been suggested as a regulator of stage differentiation in Trypanosoma cruzi. Using a yeast two-hybrid system we have begun to characterize the downstream substrates of T. cruzi PKA. We identified several members of the trans-sialidase super family by this approach. Immunoprecitation demonstrated that a TcPKAc monoclonal antibody was able to pull-down proteins recognized by trans-sialidase antibodies as well as a SA85-1.1 antibody and vice versa. An in vitro phosphorylation assay demonstrated that PKA phosphorylated the recombinant protein of an active trans-sialidase. In addition, a phospho-(Ser/Thr) PKA substrate antibody detected bands on immunoblot analysis of trans-sialidase antibody precipitated proteins from parasite lysate and the media of L(6)E(9) myoblasts infected with trypomastigotes as well as from a SA85-1.1 antibody precipitated proteins from parasite lysate. Immunofluorescence analysis suggested that some TcPKAc localizes to the plasma membrane surface of trypomastigotes. The identified trans-sialidases have PKA consensus phosphorylation sites located near the endoplasmic reticulum retention motif in the N-terminal. These data support that PKA phosphorylates trans-sialidase super family members in vivo.
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Affiliation(s)
- Yi Bao
- Department of Pathology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA
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Localization and developmental regulation of a dispersed gene family 1 protein in Trypanosoma cruzi. Infect Immun 2009; 78:231-40. [PMID: 19841080 DOI: 10.1128/iai.00780-09] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The dispersed gene family 1 (DGF-1) is the fifth largest gene family in the Trypanosoma cruzi genome, with over 500 members (11). Many of the predicted DGF-1 protein products have several transmembrane domains and N-glycosylation and phosphorylation sites and were thought to localize in the plasma membrane. Here, we report that affinity-purified antibodies against a region of one of these proteins (DGF-1.2) localized it intracellularly in different stages of the parasite. DGF-1.2 is more abundant in the amastigote stage than in trypomastigotes and epimastigotes, as detected by immunofluorescence and Western blot analyses. The protein changed localization during intracellular or extracellular differentiation from the trypomastigote to the amastigote stage, where it finally localized to small bodies in close contact with the inner side of the amastigote plasma membrane. DGF-1.2 did not colocalize with markers of other subcellular organelles, such as acidocalcisomes, glycosomes, reservosomes, lipid droplets, or endocytic vesicles. During extracellular differentiation, the protein was detected in the culture medium from 0 to 22 h, peaking at 14 h. The presence of DGF-1.2 in the differentiation culture medium was confirmed by mass spectrometry analysis. Finally, when epimastigotes were subjected to starvation, there was a decrease in the labeling of the cells and, in Western blots, the appearance of bands of lower molecular mass, suggesting its cleavage. These results represent the first report of direct immunodetection and developmental expression and secretion of a DGF-1 protein.
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Abstract
Protein kinase A (PKA) is an important mediator of many signal transduction pathways that occur in eukaryotic cells, and it has been implicated as a regulator of stage differentiation in Trypanosoma cruzi. To evaluate the importance of the PKA catalytic subunit of T. cruzi (TcPKAc), a gene encoding a PKA inhibitor (PKI) containing a specific PKA pseudosubstrate, R-R-N-A, was subcloned into a pTREX vector and introduced into epimastigotes by electroporation. Expression of PKI has a lethal effect in this parasite. Similarly, a pharmacological inhibitor, H89, killed epimastigotes at a concentration of 10 muM. To understand the biology of PKA, identification of the particular substrates of this enzyme is essential. Using a yeast two-hybrid system, 38 candidates interacting with TcPKAc were identified. Eighteen of these were hypothetical proteins with unknown functions, while the others had putative or known functions. The entire open reading frames of eight genes presumably important in regulating T. cruzi growth, adaptation, and differentiation, including a type III PI3 kinase (Vps34), a putative PI3 kinase, a putative mitogen-activated extracellular signal-regulated kinase, a cyclic AMP (cAMP)-specific phosphodiesterase (PDEC2), a hexokinase, a putative ATPase, a DNA excision repair protein, and an aquaporin were confirmed to interact with TcPKAc in the yeast Saccharomyces cerevisiae under the highest stringency selection conditions, and PKA phosphorylated the recombinant proteins of these genes. Taken together, these findings demonstrate the importance of cAMP-PKA signaling in this organism.
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Inhibition of proteasome activity blocks Trypanosoma cruzi growth and metacyclogenesis. Parasitol Res 2008; 103:941-51. [DOI: 10.1007/s00436-008-1081-6] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2008] [Accepted: 06/03/2008] [Indexed: 11/26/2022]
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Einicker-Lamas M, Nascimento MTC, Masuda CA, Oliveira MM, Caruso-Neves C. Trypanosoma cruzi epimastigotes: regulation of myo-inositol transport by effectors of protein kinases A and C. Exp Parasitol 2007; 117:171-7. [PMID: 17586497 DOI: 10.1016/j.exppara.2007.04.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2007] [Revised: 04/11/2007] [Accepted: 04/23/2007] [Indexed: 01/10/2023]
Abstract
Inositol is the precursor for most Trypanosoma cruzi surface molecules, including phosphoinositides, glycosylinositolphospholipids and glycosylphosphatidylinositol anchors. As the parasite is an inositol auxotroph, the inositol transport system might be a potential target for new trypanocide drugs, as some of its properties are different from its mammalian counterpart. Here, we investigated the modulation exerted by effectors of PKA and PKC on this transport system to comply with the parasite physiology. Pre-incubation of the cells with either dibutyryl-cyclic AMP (25 microM) or forskolin (30 microM) decreased the myo-inositol uptake by half, this effect being reversed by KT5720 (PKA inhibitor). Conversely, pre-incubation of the cells with PMA (2.8 microg/ml) or serum (5%) had a approximately 50% stimulation in myo-inositol uptake, being this effect reversed by staurosporine (0.5 microM) or sphingosine (10 microM). These results allow us to conclude that the myo-inositol transport system in T. cruzi epimastigotes is inhibited by PKA and stimulated by PKC effectors.
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Affiliation(s)
- Marcelo Einicker-Lamas
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, 21941-590 Rio de Janeiro, Brazil
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Gluenz E, Taylor MC, Kelly JM. The Trypanosoma cruzi metacyclic-specific protein Met-III associates with the nucleolus and contains independent amino and carboxyl terminal targeting elements. Int J Parasitol 2007; 37:617-25. [PMID: 17239886 PMCID: PMC2424140 DOI: 10.1016/j.ijpara.2006.11.016] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2006] [Revised: 11/20/2006] [Accepted: 11/22/2006] [Indexed: 11/24/2022]
Abstract
Metacyclogenesis in Trypanosoma cruzi involves the differentiation of replicating non-infective epimastigotes into non-replicating metacyclic trypomastigotes. This pre-adapts parasites for infection of the mammalian host and is characterised by several morphological changes and structural alterations to the nucleus, including nucleolar disaggregation. Experimental investigation of these developmental processes has been hampered by a lack of robust molecular markers. Here, we describe the precise temporal expression of the T. cruzi-specific protein Met-III, in the genome reference strain CL Brener. Expression is restricted to metacyclics in the insect stages of the life-cycle and is rapidly down-regulated following invasion of mammalian cells. Met-III localises to dispersed foci typical of the disassembled nucleolus in metacyclics and to the discrete single nucleolus of cells soon after macrophage invasion. To identify elements that target Met-III, we generated a series of tagged green fluorescent protein fusion proteins and examined their sub-nuclear location in transformed parasites. These experiments demonstrated that amino and carboxyl terminal fragments, characterised by clusters of basic residues, could independently mediate nucleolar sequestration. To investigate the function of Met-III, we used gene deletion. This showed that Met-III is not required for the development of metacyclic trypomastigotes and that null mutants can complete the life-cycle in vitro.
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Affiliation(s)
| | | | - John M. Kelly
- Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
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Díaz-Benjumea R, Laxman S, Hinds T, Beavo J, Rascón A. Characterization of a novel cAMP-binding, cAMP-specific cyclic nucleotide phosphodiesterase (TcrPDEB1) from Trypanosoma cruzi. Biochem J 2006; 399:305-14. [PMID: 16776650 PMCID: PMC1609912 DOI: 10.1042/bj20060757] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Trypanosoma cruzi, the causative agent of Chagas disease, encodes a number of different cAMP-specific PDE (phosphodiesterase) families. Here we report the identification and characterization of TcrPDEB1 and its comparison with the previously identified TcrPDEB2 (formerly known as TcPDE1). These are two different PDE enzymes of the TcrPDEB family, named in accordance with the recent recommendations of the Nomenclature Committee for Kinetoplast PDEs [Kunz, Beavo, D'Angelo, Flawia, Francis, Johner, Laxman, Oberholzer, Rascon, Shakur et al. (2006) Mol. Biochem. Parasitol. 145, 133-135]. Both enzymes show resistance to inhibition by many mammalian PDE inhibitors, and those that do inhibit do so with appreciable differences in their inhibitor profiles for the two enzymes. Both enzymes contain two GAF (cGMP-specific and -stimulated phosphodiesterases, Anabaena adenylate cyclases and Escherichia coli FhlA) domains and a catalytic domain highly homologous with that of the T. brucei TbPDE2/TbrPDEB2 family. The N-terminus+GAF-A domains of both enzymes showed significant differences in their affinities for cyclic nucleotide binding. Using a calorimetric technique that allows accurate measurements of low-affinity binding sites, the TcrPDEB2 N-terminus+GAF-A domain was found to bind cAMP with an affinity of approximately 500 nM. The TcrPDEB1 N-terminus+GAF-A domain bound cAMP with a slightly lower affinity of approximately 1 muM. The N-terminus+GAF-A domain of TcrPDEB1 did not bind cGMP, whereas the N-terminus+GAF-A domain of TcrPDEB2 bound cGMP with a low affinity of approximately 3 muM. GAF domains homologous with those found in these proteins were also identified in related trypanosomatid parasites. Finally, a fluorescent cAMP analogue, MANT-cAMP [2'-O-(N-methylanthraniloyl)adenosine-3',5'-cyclic monophosphate], was found to be a substrate for the TcPDEB1 catalytic domain, opening the possibility of using this molecule as a substrate in non-radioactive, fluorescence-based PDE assays, including screening for trypanosome PDE inhibitors.
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Affiliation(s)
- Rocío Díaz-Benjumea
- *Instituto de Biología Experimental, Universidad Central de Venezuela, Box 47069, Caracas, Venezuela
| | - Sunil Laxman
- †Department of Pharmacology, Box 357280, University of Washington, Seattle, WA 98195-7280, U.S.A
| | - Thomas R. Hinds
- †Department of Pharmacology, Box 357280, University of Washington, Seattle, WA 98195-7280, U.S.A
| | - Joseph A. Beavo
- †Department of Pharmacology, Box 357280, University of Washington, Seattle, WA 98195-7280, U.S.A
| | - Ana Rascón
- *Instituto de Biología Experimental, Universidad Central de Venezuela, Box 47069, Caracas, Venezuela
- To whom correspondence should be addressed (email )
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Fernandes AB, Neira I, Ferreira AT, Mortara RA. Cell invasion by Trypanosoma cruzi amastigotes of distinct infectivities: studies on signaling pathways. Parasitol Res 2006; 100:59-68. [PMID: 16791632 DOI: 10.1007/s00436-006-0236-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2006] [Accepted: 05/09/2006] [Indexed: 11/26/2022]
Abstract
Trypanosoma cruzi metacyclic trypomastigotes of the major phylogenetic lineages use specific signaling pathways to invade host cells. Using a panel of drugs, we studied if the differences in the ability of extracellular amastigotes (EA) from G (T. cruzi I) and CL (T. cruzi II) strains to invade host cells could be associated to activation of specific signaling routes. Sonicated extracts from G or CL strain EA induced transient raises in HeLa cell intracellular Ca(2+) levels in a dose-dependent manner. Treatment of EA with drugs that affect Ca(2+) release from inositol-1,4,5-triphosphate-sensitive stores did not significantly affect the infectivity of either strain, whereas EA of both strains treated with ionomycin plus NH(4)Cl or nigericin that release Ca(2+) from acidocalcisomes had their infectivity reduced. Treatment of parasites with adenylate cyclase activator forskolin increased the infectivity of both strains towards HeLa cells. These data, taken together, suggest that, for host cell invasion, G and CL strain EA engage signaling pathways that lead to an increase of cyclic adenosine monophosphate and Ca(2+) mobilization from acidocalcisomes. Moreover, treatment of EA with genistein reduced by approximately 45% the invasion of HeLa cells by G but not by CL strain, implicating a protein tyrosine kinase in the process. In line with this, HeLa cell extracts contained a protein tyrosine kinase activity that mediated the phosphorylation of 87- and 175-kDa polypeptides of EA from G but not from CL strain. Regarding the target cell response, the activation of host PI3 kinase appears to be required for invasion by either strain as treatment of HeLa cells with wortmannin reduced EA infectivity. These data overall reinforce the concept that cell invasion by T. cruzi EA markedly differs from the process involving metacyclic trypomastigotes.
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Affiliation(s)
- Adriana B Fernandes
- Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo-UNIFESP, Escola Paulista de Medicina, Rua Botucatu, 862 6th Floor, 04023-062, São Paulo, Brazil
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Huang H, Weiss LM, Nagajyothi F, Tanowitz HB, Wittner M, Orr GA, Bao Y. Molecular cloning and characterization of the protein kinase A regulatory subunit of Trypanosoma cruzi. Mol Biochem Parasitol 2006; 149:242-5. [PMID: 16815565 DOI: 10.1016/j.molbiopara.2006.05.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2005] [Revised: 04/24/2006] [Accepted: 05/23/2006] [Indexed: 10/24/2022]
Affiliation(s)
- Huan Huang
- Department of Pathology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA.
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Kunz S, Oberholzer M, Seebeck T. A FYVE-containing unusual cyclic nucleotide phosphodiesterase from Trypanosoma cruzi. FEBS J 2006; 272:6412-22. [PMID: 16336277 DOI: 10.1111/j.1742-4658.2005.05039.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Cyclic-nucleotide-specific phosphodiesterases (PDEs) are key players in the intracellular signaling pathways of the important human pathogen Trypanosoma cruzi. We report herein the identification of an unusual PDE from this protozoal organism. This enzyme, TcrPDEC, is a member of the class I PDEs, as determined from the presence of a characteristic signature sequence and from the conservation of a number of functionally important amino acid residues within its catalytic domain. Class I PDEs include a large number of PDEs from eukaryotes, among them all 11 human PDE families. Unusually for an enzyme of this class, TcrPDEC contains a FYVE-type domain in its N-terminal region, followed by two closely spaced coiled-coil domains. Its catalytic domain is located in the middle of the polypeptide chain, whereas all other class I enzymes contain their catalytic domains in their C-terminal parts. TcrPDEC can complement a PDE-deficient yeast strain. Unexpectedly for a kinetoplastid PDE, TcrPDEC is a dual-specificity PDE that accepts both cAMP and cGMP as its substrates.
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Affiliation(s)
- Stefan Kunz
- Institute of Cell Biology, University of Bern, Bern, Switzerland
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Oury B, Tarrieu F, Monte-Alegre A, Ouaissi A. Trypanosoma cruzi: Sequence polymorphism of the gene encoding the Tc52 immunoregulatory-released factor in relation to the phylogenetic diversity of the species. Exp Parasitol 2005; 111:198-206. [PMID: 16199037 DOI: 10.1016/j.exppara.2005.07.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2004] [Revised: 07/04/2005] [Accepted: 07/15/2005] [Indexed: 10/25/2022]
Abstract
We have previously identified a Trypanosoma cruzi gene encoding a protein named Tc52 sharing structural and functional properties with the thioredoxin and glutaredoxin family involved in thiol-disulfide redox reactions. Gene targeting strategy and immunological studies allowed showing that Tc52 is among T. cruzi virulence factors. Taking into account that T. cruzi has a genetic variability that might be important determinant that governs the different behaviour of T. cruzi clones in vitro and in vivo, we thought it was of interest to analyse the sequence polymorphism of Tc52 gene in several reference clones. The DNA sequences of 12 clones which represent the whole genetic diversity of T. cruzi allowed showing that 40 amino-acid positions over 400 analysed are targets for mutations. A number of residues corresponding to putative amino-acids playing a role in GSH binding and/or enzymatic function and others located nearby are subject to mutations. Although the immunological analysis showed that Tc52 is present in parasite extracts from different clones, it is possible that the amino-acid differences could affect the enzymatic and/or the immunomodulatory function of Tc52 variants and therefore the parasite phenotype.
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Affiliation(s)
- Bruno Oury
- Institut de Recherche pour le Développement (IRD), Unité de Recherche no 8 Pathogénie des Trypanosomatidae, Montpellier, France.
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Flawiá MM, Téllez-Iñón MT, Torres HN. Signal transduction mechanisms in Trypanosoma cruzi. ACTA ACUST UNITED AC 2005; 13:30-3. [PMID: 15275164 DOI: 10.1016/s0169-4758(96)10070-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Trypanosoma cruzi, the etiological agent of Chagas disease, is an adequate model for studies on the evolution of signal transduction pathways. These pathways involve molecular entities such as membrane receptors, transduction G proteins, protein kinases and second messengers (Ca(2+), cyclic AMP, cyclic GMP, nitric oxide). In this article, Mirtha M. Flawiá, María T. Téllez-Iñón and Héctor N. Torres describe the studies performed on T. cruzi transduction pathways and their role in the control of metacyclogenesis and cell motility.
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Affiliation(s)
- M M Flawiá
- Instituto de investigaciones en Ingenieria Genética y Biología Molecular (CONICET and Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires), Vuelta de Obligado 2490. 1428 Buenos Aires, Argentina
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Equinet L, Bapteste E, Thellier M, Ouarzane-Amara M, Vivarès CP, Desportes-Livage I, Doerig C. The genes encoding cAMP-dependent protein kinase catalytic subunit homologues of the microsporidia Encephalitozoon intestinalis and E. cuniculi: molecular characterisation and phylogenetic analysis. Parasitol Int 2005; 53:277-85. [PMID: 15464436 DOI: 10.1016/j.parint.2004.03.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2003] [Revised: 02/11/2004] [Accepted: 03/03/2004] [Indexed: 11/22/2022]
Abstract
A gene encoding a protein kinase was identified by homology-based PCR amplification in Encephalitozoon intestinalis, a microsporidian parasite pathogenic to humans, and its orthologue has been identified by database mining in the genome of the related species E. cuniculi, whose sequence has been recently published. Phylogenetic analysis revealed that the proteins encoded by these genes are homologues of the cAMP-dependent protein kinase catalytic subunits (PKAc). Southern blot analysis indicated that the EiPKAc gene is present in two copies in the E. intestinalis genome, whereas the E. cuniculi orthologue (EcPKAc) is a single copy gene. RT-PCR data showed that the EiPKAc gene is expressed in at least one of the intracellular stages during infection of the mammalian host cell by E. intestinalis.
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Affiliation(s)
- Leila Equinet
- INSERM U609, Wellcome Centre for Molecular Parasitology, University of Glasgow, 56 Dumbarton Road, Glasgow G11 6NU, Scotland, UK
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González J, Cornejo A, Santos MRM, Cordero EM, Gutiérrez B, Porcile P, Mortara RA, Sagua H, Da Silveira JF, Araya JE. A novel protein phosphatase 2A (PP2A) is involved in the transformation of human protozoan parasite Trypanosoma cruzi. Biochem J 2003; 374:647-56. [PMID: 12737627 PMCID: PMC1223626 DOI: 10.1042/bj20030215] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2003] [Revised: 05/02/2003] [Accepted: 05/09/2003] [Indexed: 01/06/2023]
Abstract
Here we provide evidence for a critical role of PP2As (protein phosphatase 2As) in the transformation of Trypanosoma cruzi. In axenic medium at pH 5.0, trypomastigotes rapidly transform into amastigotes, a process blocked by okadaic acid, a potent PP2A inhibitor, at concentrations as low as 0.1 microM. 1-Norokadaone, an inactive okadaic acid analogue, did not affect the transformation. Electron microscopy studies indicated that okadaic acid-treated trypomastigotes had not undergone ultrastructural modifications, reinforcing the idea that PP2A inhibits transformation. Using a microcystin-Sepharose affinity column we purified the native T. cruzi PP2A. The enzyme displayed activity against 32P-labelled phosphorylase a that was inhibited in a dose-dependent manner by okadaic acid. The protein was also submitted to MS and, from the peptides obtained, degenerate primers were used to clone a novel T. cruzi PP2A enzyme by PCR. The isolated gene encodes a protein of 303 amino acids, termed TcPP2A, which displayed a high degree of homology (86%) with the catalytic subunit of Trypanosoma brucei PP2A. Northern-blot analysis revealed the presence of a major 2.1-kb mRNA hybridizing in all T. cruzi developmental stages. Southern-blot analysis suggested that the TcPP2A gene is present in low copy number in the T. cruzi genome. These results are consistent with the mapping of PP2A genes in two chromosomal bands by pulsed-field gel electrophoresis and chromoblot hybridization. Our studies suggest that in T. cruzi PP2A is important for the complete transformation of trypomastigotes into amastigotes during the life cycle of this protozoan parasite.
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Affiliation(s)
- Jorge González
- Parasitology Unit, Department of Medical Technology, University of Antofagasta, Antofagasta, PO Box 170, Chile.
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Carvalho-Moreira CJ, Spata MCD, Coura JR, Garcia ES, Azambuja P, Gonzalez MS, Mello CB. In vivo and in vitro metacyclogenesis tests of two strains of Trypanosoma cruzi in the triatomine vectors Triatoma pseudomaculata and Rhodnius neglectus: short/long-term and comparative study. Exp Parasitol 2003; 103:102-11. [PMID: 12880586 DOI: 10.1016/s0014-4894(03)00072-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Metacyclogenesis of Trypanosoma cruzi of the Y and Berenice strains was studied in Triatoma pseudomaculata and Rhodnius neglectus. Results in vivo showed a higher production of metacyclic trypomastigotes in R. neglectus' digestive tube than in T. pseudomaculata. In vitro experiments were also carried out in order to compare the behavior of culture forms of T. cruzi incubated in extracts of different compartments (stomach, intestine, and rectum) of the digestive tract of both species of triatomines. A higher percentage of metacyclic trypomastigotes for both parasite strains, Y and Berenice, was detected in the rectum extract of R. neglectus in comparison to that from T. pseudomaculata. The same results were obtained with in vitro experiments, using parasites incubated in urine from each of those vectors. The adhesion of parasites to the incubated rectum epithelial cells was also compared. In incubations with the Y strain no significant differences were detected between the two triatomine species but, however, with the Berenice strain the mean percentage of cells with adhered parasites was higher in R. neglectus than in T. pseudomaculata.
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Affiliation(s)
- C J Carvalho-Moreira
- Department of Tropical Medicine, Oswaldo Cruz Institute, FIOCRUZ, Av. Brasil 4365, Rio de Janeiro, CEP 21045 RJ, Brazil
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