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A Trypanosoma cruzi zinc finger protein that is implicated in the control of epimastigote-specific gene expression and metacyclogenesis. Parasitology 2020; 148:1171-1185. [PMID: 33190649 PMCID: PMC8312218 DOI: 10.1017/s0031182020002176] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Trypanosoma cruzi has three biochemically and morphologically distinct developmental stages that are programmed to rapidly respond to environmental changes the parasite faces during its life cycle. Unlike other eukaryotes, Trypanosomatid genomes contain protein coding genes that are transcribed into polycistronic pre-mRNAs and have their expression controlled by post-transcriptional mechanisms. Transcriptome analyses comparing three stages of the T. cruzi life cycle revealed changes in gene expression that reflect the parasite adaptation to distinct environments. Several genes encoding RNA binding proteins (RBPs), known to act as key post-transcriptional regulatory factors, were also differentially expressed. We characterized one T. cruzi RBP, named TcZH3H12, which contains a zinc finger domain and is up-regulated in epimastigotes compared to trypomastigotes and amastigotes. TcZC3H12 knockout (KO) epimastigotes showed decreased growth rates and increased capacity to differentiate into metacyclic trypomastigotes. Transcriptome analyses comparing wild type and TcZC3H12 KOs revealed a TcZC3H12-dependent expression of epimastigote-specific genes such as genes encoding amino acid transporters and proteins associated with differentiation (PADs). RNA immunoprecipitation assays showed that transcripts from the PAD family interact with TcZC3H12. Taken together, these findings suggest that TcZC3H12 positively regulates the expression of genes involved in epimastigote proliferation and also acts as a negative regulator of metacyclogenesis.
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Romagnoli BAA, Holetz FB, Alves LR, Goldenberg S. RNA Binding Proteins and Gene Expression Regulation in Trypanosoma cruzi. Front Cell Infect Microbiol 2020; 10:56. [PMID: 32154189 PMCID: PMC7045066 DOI: 10.3389/fcimb.2020.00056] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Accepted: 02/03/2020] [Indexed: 01/24/2023] Open
Abstract
The regulation of gene expression in trypanosomatids occurs mainly at the post-transcriptional level. In the case of Trypanosoma cruzi, the characterization of messenger ribonucleoprotein (mRNP) particles has allowed the identification of several classes of RNA binding proteins (RBPs), as well as non-canonical RBPs, associated with mRNA molecules. The protein composition of the mRNPs as well as the localization and functionality of the mRNAs depend on their associated proteins. mRNPs can also be organized into larger complexes forming RNA granules, which function as stress granules or P-bodies depending on the associated proteins. The fate of mRNAs in the cell, and consequently the genes expressed, depends on the set of proteins associated with the messenger molecule. These proteins allow the coordinated expression of mRNAs encoding proteins that are related in function, resulting in the formation of post-transcriptional operons. However, the puzzle posed by the combinatorial association of sets of RBPs with mRNAs and how this relates to the expressed genes remain to be elucidated. One important tool in this endeavor is the use of the CRISPR/CAS system to delete genes encoding RBPs, allowing the evaluation of their effect on the formation of mRNP complexes and associated mRNAs in the different compartments of the translation machinery. Accordingly, we recently established this methodology for T. cruzi and deleted the genes encoding RBPs containing zinc finger domains. In this manuscript, we will discuss the data obtained and the potential of the CRISPR/CAS methodology to unveil the role of RBPs in T. cruzi gene expression regulation.
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Affiliation(s)
- Bruno A A Romagnoli
- Gene Expression Regulation Laboratory, Institute Carlos Chagas, Curitiba, Brazil
| | - Fabiola B Holetz
- Gene Expression Regulation Laboratory, Institute Carlos Chagas, Curitiba, Brazil
| | - Lysangela R Alves
- Gene Expression Regulation Laboratory, Institute Carlos Chagas, Curitiba, Brazil
| | - Samuel Goldenberg
- Gene Expression Regulation Laboratory, Institute Carlos Chagas, Curitiba, Brazil
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Belew AT, Junqueira C, Rodrigues-Luiz GF, Valente BM, Oliveira AER, Polidoro RB, Zuccherato LW, Bartholomeu DC, Schenkman S, Gazzinelli RT, Burleigh BA, El-Sayed NM, Teixeira SMR. Comparative transcriptome profiling of virulent and non-virulent Trypanosoma cruzi underlines the role of surface proteins during infection. PLoS Pathog 2017; 13:e1006767. [PMID: 29240831 PMCID: PMC5746284 DOI: 10.1371/journal.ppat.1006767] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2017] [Revised: 12/28/2017] [Accepted: 11/22/2017] [Indexed: 01/23/2023] Open
Abstract
Trypanosoma cruzi, the protozoan that causes Chagas disease, has a complex life cycle involving several morphologically and biochemically distinct stages that establish intricate interactions with various insect and mammalian hosts. It has also a heterogeneous population structure comprising strains with distinct properties such as virulence, sensitivity to drugs, antigenic profile and tissue tropism. We present a comparative transcriptome analysis of two cloned T. cruzi strains that display contrasting virulence phenotypes in animal models of infection: CL Brener is a virulent clone and CL-14 is a clone that is neither infective nor pathogenic in in vivo models of infection. Gene expression analysis of trypomastigotes and intracellular amastigotes harvested at 60 and 96 hours post-infection (hpi) of human fibroblasts revealed large differences that reflect the parasite’s adaptation to distinct environments during the infection of mammalian cells, including changes in energy sources, oxidative stress responses, cell cycle control and cell surface components. While extensive transcriptome remodeling was observed when trypomastigotes of both strains were compared to 60 hpi amastigotes, differences in gene expression were much less pronounced when 96 hpi amastigotes and trypomastigotes of CL Brener were compared. In contrast, the differentiation of the avirulent CL-14 from 96 hpi amastigotes to extracellular trypomastigotes was associated with considerable changes in gene expression, particularly in gene families encoding surface proteins such as trans-sialidases, mucins and the mucin associated surface proteins (MASPs). Thus, our comparative transcriptome analysis indicates that the avirulent phenotype of CL-14 may be due, at least in part, to a reduced or delayed expression of genes encoding surface proteins that are associated with the transition of amastigotes to trypomastigotes, an essential step in the establishment of the infection in the mammalian host. Confirming the role of members of the trans-sialidase family of surface proteins for parasite differentiation, transfected CL-14 constitutively expressing a trans-sialidase gene displayed faster kinetics of trypomastigote release in the supernatant of infected cells compared to wild type CL-14. Chagas disease, caused by the protozoan parasite Trypanosoma cruzi, is an infection that occurs in several Latin American countries, resulting in a mild illness or in severe damage of the heart and intestinal tract. Such a broad spectrum of clinical manifestations observed in Chagas disease patients is likely due to differences in host susceptibility as well as to a large heterogeneity among T. cruzi isolates. The identification of virulence factors that are differentially expressed in the parasite population is a valuable strategy for understanding of the distinct interactions that occur between this pathogen and its host, which may or may not lead to pathogenesis. By comparing the gene expression profiles of two T. cruzi strains that display contrasting virulence phenotypes in animal models of infection, we identified a central role for genes encoding surface proteins that is associated with the differentiation from intracellular replicative amastigotes to infective trypomastigotes. We showed that the expression of these genes occurs differentially within the two strains and this difference may be a factor that impacts parasite survival and dissemination in the mammalian host.
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Affiliation(s)
- A. Trey Belew
- Department of Cell Biology and Molecular Genetics and Center for Bioinformatics and Computational Biology, University of Maryland, College Park, Maryland, United States of America
| | - Caroline Junqueira
- Centro de Pesquisas Rene Rachou, Fundação Oswaldo Cruz, Belo Horizonte, Minas Gerais, Brazil
| | - Gabriela F. Rodrigues-Luiz
- Departamento de Parasitologia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Bruna M. Valente
- Departamento de Bioquímica e Imunologia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Antonio Edson R. Oliveira
- Departamento de Bioquímica e Imunologia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Rafael B. Polidoro
- Departmento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo, São Paulo, São Paulo, Brazil
| | - Luciana W. Zuccherato
- Departamento de Bioquímica e Imunologia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Daniella C. Bartholomeu
- Departamento de Parasitologia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Sergio Schenkman
- Departmento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo, São Paulo, São Paulo, Brazil
| | - Ricardo T. Gazzinelli
- Centro de Pesquisas Rene Rachou, Fundação Oswaldo Cruz, Belo Horizonte, Minas Gerais, Brazil
- Departamento de Bioquímica e Imunologia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Barbara A. Burleigh
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, Massachusetts, United States of America
| | - Najib M. El-Sayed
- Department of Cell Biology and Molecular Genetics and Center for Bioinformatics and Computational Biology, University of Maryland, College Park, Maryland, United States of America
- * E-mail: (SMRT); (NES)
| | - Santuza M. R. Teixeira
- Departamento de Bioquímica e Imunologia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
- * E-mail: (SMRT); (NES)
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Alves LR, Oliveira C, Mörking PA, Kessler RL, Martins ST, Romagnoli BAA, Marchini FK, Goldenberg S. The mRNAs associated to a zinc finger protein from Trypanosoma cruzi shift during stress conditions. RNA Biol 2014; 11:921-33. [PMID: 25180711 PMCID: PMC4179965 DOI: 10.4161/rna.29622] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Trypanosome gene expression is regulated almost exclusively at the posttranscriptional level, through mRNA stability, storage and degradation. Here, we characterize the ribonucleoprotein complex (mRNPs) corresponding to the zinc finger protein TcZC3H39 from T. cruzi comparing cells growing in normal conditions and under nutritional stress. The nutritional stress is a key step during T. cruzi differentiation from epimastigote form to human infective metacyclic trypomastigote form. The mechanisms by which the stress, altogether with other stimuli, triggers differentiation is not well understood. This work aims to characterize the TcZC3H39 protein during stress response. Using cells cultured in normal and stress conditions, we observed a dynamic change in TcZC3H39 granule distribution, which appeared broader in stressed epimastigotes. The protein core of the TcZC3H39-mRNP is composed of ribosomes, translation factors and RBPs. The TcZC3H39-mRNP could act sequestering highly expressed mRNAs and their associated ribosomes, potentially slowing translation in stress conditions. A shift were observed in the mRNAs associated with TcZC3H39: the number of targets in unstressed epimastigotes was smaller than that in stressed parasites, with no clear functional clustering in normal conditions. By contrast, in stressed parasites, the targets of TcZC3H39 were mRNAs encoding ribosomal proteins and a remarkable enrichment in mRNAs for the cytochrome c complex (COX), highly expressed mRNAs in the replicative form. This identification of a new component of RNA granules in T. cruzi, the TcZC3H39 protein, provides new insight into the mechanisms involved in parasite stress responses and the regulation of gene expression during T. cruzi differentiation.
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Mörking PA, Rampazzo RDCP, Walrad P, Probst CM, Soares MJ, Gradia DF, Pavoni DP, Krieger MA, Matthews K, Goldenberg S, Fragoso SP, Dallagiovanna B. The zinc finger protein TcZFP2 binds target mRNAs enriched during Trypanosoma cruzi metacyclogenesis. Mem Inst Oswaldo Cruz 2012; 107:790-9. [DOI: 10.1590/s0074-02762012000600014] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2011] [Accepted: 04/12/2012] [Indexed: 11/22/2022] Open
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Kramer S, Carrington M. Trans-acting proteins regulating mRNA maturation, stability and translation in trypanosomatids. Trends Parasitol 2010; 27:23-30. [PMID: 20609625 PMCID: PMC3070815 DOI: 10.1016/j.pt.2010.06.011] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2010] [Revised: 06/05/2010] [Accepted: 06/07/2010] [Indexed: 12/30/2022]
Abstract
In trypanosomatids, alterations in gene expression in response to intrinsic or extrinsic signals are achieved through post-transcriptional mechanisms. In the last 20 years, research has concentrated on defining the responsible cis-elements in the untranslated regions of several regulated mRNAs. More recently, the focus has shifted towards the identification of RNA-binding proteins that act as trans-acting factors. Trypanosomatids have a large number of predicted RNA-binding proteins of which the vast majority have no orthologues in other eukaryotes. Several RNA-binding proteins have been shown to bind and/or regulate the expression of a group of mRNAs that code for functionally related proteins, indicating the possible presence of co-regulated mRNA cohorts.
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Affiliation(s)
- Susanne Kramer
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, UK, CB2 1QW
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Genome-wide in silico screen for CCCH-type zinc finger proteins of Trypanosoma brucei, Trypanosoma cruzi and Leishmania major. BMC Genomics 2010; 11:283. [PMID: 20444260 PMCID: PMC2873481 DOI: 10.1186/1471-2164-11-283] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2010] [Accepted: 05/05/2010] [Indexed: 11/24/2022] Open
Abstract
Background CCCH type zinc finger proteins are RNA binding proteins with regulatory functions at all stages of mRNA metabolism. The best-characterized member, tritetraproline (TTP), binds to AU rich elements in 3' UTRs of unstable mRNAs, mediating their degradation. In kinetoplastids, CCCH type zinc finger proteins have been identified as being involved in the regulation of the life cycle and possibly the cell cycle. To date, no systematic listing of CCCH proteins in kinetoplastids is available. Results We have identified the complete set of CCCH type zinc finger proteins in the available genomes of the kinetoplastid protozoa Trypanosoma brucei, Trypanosoma cruzi and Leishmania major. One fifths (20%) of all CCCH motifs fall into non-conventional classes and many had not been previously identified. One third of all CCCH proteins have more than one CCCH motif, suggesting multivalent RNA binding. One third have additional recognizable domains. The vast majority are unique to Kinetoplastida or to a subgroup within. Two exceptions are of interest: the putative orthologue of the mRNA nuclear export factor Mex67 and a 3'-5' exoribonuclease restricted to Leishmania species. CCCH motifs are absent from these proteins in other organisms and might be unique, novel features of the Kinetoplastida homologues. Of the others, several have a predicted, and in one case experimentally confirmed, connection to the ubiquitination pathways, for instance a HECT-type E3 ubiquitin ligase. The total number of kinetoplastid CCCH proteins is similar to the number in higher eukaryotes but lower than in yeast. A comparison of the genomic loci between the Trypanosomatidae homologues provides insight into both the evolution of the CCCH proteins as well as the CCCH motifs. Conclusion This study provides the first systematic listing of the Kinetoplastida CCCH proteins. The number of CCCH proteins with more then one CCCH motif is larger than previously estimated, due to the identification of non-conventional CCCH motifs. Experimental approaches are now necessary to examine the functions of the many unique CCCH proteins as well as the function of the putative Mex67 and the Leishmania 3'-5' exoribonuclease.
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Alves LR, Avila AR, Correa A, Holetz FB, Mansur FCB, Manque PA, de Menezes JPB, Buck GA, Krieger MA, Goldenberg S. Proteomic analysis reveals the dynamic association of proteins with translated mRNAs in Trypanosoma cruzi. Gene 2010; 452:72-8. [PMID: 20060445 DOI: 10.1016/j.gene.2009.12.009] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2009] [Revised: 11/22/2009] [Accepted: 12/26/2009] [Indexed: 01/09/2023]
Abstract
Gene regulation is mainly post-transcriptional in trypanosomatids. The stability of mRNA and access to polysomes are thought to be tightly regulated, allowing Trypanosoma cruzi to adapt to the different environmental conditions during its life cycle. Post-transcriptional regulation requires the association between mRNAs and certain proteins to form mRNP complexes. We investigated the dynamic association between proteins and mRNAs, using poly(T) beads to isolate and characterize proteins and protein complexes bound to poly-A+ mRNAs. The protein content of these fractions was analyzed by mass spectrometry (LC-MS/MS). We identified 542 protein component of the mRNP complexes associated with mRNAs. Twenty-four of the proteins obtained were present in all fractions, whereas some other proteins were exclusive to a particular fraction: epimastigote polysomal (0.37%) and post-polysomal (2.95%) fractions; stress polysomal (13.8%) and post-polysomal (40.78%) fractions. Several proteins known to be involved in mRNA metabolism were identified, and this was considered important as it made it possible to confirm the reliability of our mRNP isolation approach. This procedure allowed us to have a first insight into the composition and dynamics of mRNPs in T. cruzi.
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Affiliation(s)
- Lysangela R Alves
- Instituto Carlos Chagas, Laboratório de Regulação da Expressão Gênica, Curitiba, Paraná, Brazil
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Rodriguez-Soca Y, Munteanu CR, Dorado J, Pazos A, Prado-Prado FJ, González-Díaz H. Trypano-PPI: A Web Server for Prediction of Unique Targets in Trypanosome Proteome by using Electrostatic Parameters of Protein−protein Interactions. J Proteome Res 2009; 9:1182-90. [DOI: 10.1021/pr900827b] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Yamilet Rodriguez-Soca
- Department of Microbiology & Parasitology, Faculty of Pharmacy, University of Santiago de Compostela, 15782, Santiago de Compostela, Spain, and Department of Information and Communication Technologies, Computer Science Faculty, University of A Coruña, Campus de Elviña, 15071, A Coruña, Spain
| | - Cristian R. Munteanu
- Department of Microbiology & Parasitology, Faculty of Pharmacy, University of Santiago de Compostela, 15782, Santiago de Compostela, Spain, and Department of Information and Communication Technologies, Computer Science Faculty, University of A Coruña, Campus de Elviña, 15071, A Coruña, Spain
| | - Julián Dorado
- Department of Microbiology & Parasitology, Faculty of Pharmacy, University of Santiago de Compostela, 15782, Santiago de Compostela, Spain, and Department of Information and Communication Technologies, Computer Science Faculty, University of A Coruña, Campus de Elviña, 15071, A Coruña, Spain
| | - Alejandro Pazos
- Department of Microbiology & Parasitology, Faculty of Pharmacy, University of Santiago de Compostela, 15782, Santiago de Compostela, Spain, and Department of Information and Communication Technologies, Computer Science Faculty, University of A Coruña, Campus de Elviña, 15071, A Coruña, Spain
| | - Francisco J. Prado-Prado
- Department of Microbiology & Parasitology, Faculty of Pharmacy, University of Santiago de Compostela, 15782, Santiago de Compostela, Spain, and Department of Information and Communication Technologies, Computer Science Faculty, University of A Coruña, Campus de Elviña, 15071, A Coruña, Spain
| | - Humberto González-Díaz
- Department of Microbiology & Parasitology, Faculty of Pharmacy, University of Santiago de Compostela, 15782, Santiago de Compostela, Spain, and Department of Information and Communication Technologies, Computer Science Faculty, University of A Coruña, Campus de Elviña, 15071, A Coruña, Spain
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Avila ML, Bercovich N, Westergaard G, Levin MJ, Vázquez MP. Mapping of the protein-binding interface between splicing factors SF3b155 and p14 of Trypanosoma cruzi. Biochem Biophys Res Commun 2007; 364:26-32. [PMID: 17931603 DOI: 10.1016/j.bbrc.2007.09.090] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2007] [Accepted: 09/20/2007] [Indexed: 10/22/2022]
Abstract
SF3b155 and p14 are essential components of spliceosome core that recognize the branch point adenosine, a critical step in splicing in eukaryotes. Trypanosomes are unusual since every transcribed gene is processed by trans-splicing instead of cis-splicing. Thus, the trans-spliceosome emerges as an interesting anti-parasitic drug target since this process is not present in mammalian hosts. Here, we present the orthologues of these proteins in Trypanosoma cruzi that interact strongly with each other. To define similarities and differences with the human pair, we performed a detailed alanine scan analysis that allowed us to identify the regions and the critical amino acids of T. cruzi SF3b155 involved in interaction with p14. We demonstrate that the T. cruzi SF3b155 interface is larger and contains more complex elements than its human counterpart. Additionally, our results provide the first insights into the core of the putative mRNA processing complex of trypanosomes.
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Affiliation(s)
- M Lara Avila
- Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, INGEBI-CONICET, Vta. de obligado 2490, Buenos Aires, Argentina
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Pérez-Díaz L, Duhagon MA, Smircich P, Sotelo-Silveira J, Robello C, Krieger MA, Goldenberg S, Williams N, Dallagiovanna B, Garat B. Trypanosoma cruzi: molecular characterization of an RNA binding protein differentially expressed in the parasite life cycle. Exp Parasitol 2007; 117:99-105. [PMID: 17475252 PMCID: PMC2020836 DOI: 10.1016/j.exppara.2007.03.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2006] [Revised: 03/02/2007] [Accepted: 03/14/2007] [Indexed: 12/18/2022]
Abstract
Molecular studies have shown several peculiarities in the regulatory mechanisms of gene expression in trypanosomatids. Protein coding genes are organized in long polycistronic units that seem to be constitutively transcribed. Therefore, post-transcriptional regulation of gene expression is considered to be the main point for control of transcript abundance and functionality. Here we describe the characterization of a 17 kDa RNA-binding protein from Trypanosoma cruzi (TcRBP19) containing an RNA recognition motive (RRM). This protein is coded by a single copy gene located in a high molecular weight chromosome of T. cruzi. Orthologous genes are present in the TriTryp genomes. TcRBP19 shows target selectivity since among the different homoribopolymers it preferentially binds polyC. TcRBP19 is a low expression protein only barely detected at the amastigote stage localizing in a diffuse pattern in the cytoplasm.
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Affiliation(s)
- Leticia Pérez-Díaz
- Laboratorio de Interacciones Moleculares, Facultad de Ciencias, Iguá 4225, 11400 Montevideo, Uruguay
| | - María Ana Duhagon
- Laboratorio de Interacciones Moleculares, Facultad de Ciencias, Iguá 4225, 11400 Montevideo, Uruguay
| | - Pablo Smircich
- Laboratorio de Interacciones Moleculares, Facultad de Ciencias, Iguá 4225, 11400 Montevideo, Uruguay
| | - José Sotelo-Silveira
- Departamento de Biología Celular y Molecular, Facultad de Ciencias, Iguá 4225, 11400 Montevideo, Uruguay
- Departamento de Neurobiología Celular y Molecular, Instituto de Investigaciones Biológicas Clemente Estable Avda Italia 3318, Montevideo, Uruguay
| | - Carlos Robello
- Departamento de Bioquímica, Facultad de Medicina, Gral Flores 2125, 11800, Montevideo, Uruguay
| | - Marco Aurelio Krieger
- Instituto de Biología Molecular do Paraná, Rua Profesor Algacyr Munhoz Mader 3775, Curitiba 81350-010, Brazil
| | - Samuel Goldenberg
- Instituto de Biología Molecular do Paraná, Rua Profesor Algacyr Munhoz Mader 3775, Curitiba 81350-010, Brazil
| | - Noreen Williams
- Dept. of Microbiology and Immunology. 253 Biomedical Research Building. University at Buffalo. Buffalo 14214, NY. USA
| | - Bruno Dallagiovanna
- Instituto de Biología Molecular do Paraná, Rua Profesor Algacyr Munhoz Mader 3775, Curitiba 81350-010, Brazil
| | - Beatriz Garat
- Laboratorio de Interacciones Moleculares, Facultad de Ciencias, Iguá 4225, 11400 Montevideo, Uruguay
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Paterou A, Walrad P, Craddy P, Fenn K, Matthews K. Identification and stage-specific association with the translational apparatus of TbZFP3, a CCCH protein that promotes trypanosome life-cycle development. J Biol Chem 2006; 281:39002-13. [PMID: 17043361 PMCID: PMC2688685 DOI: 10.1074/jbc.m604280200] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The post-transcriptional control of gene expression is becoming increasingly important in the understanding of regulated events in eukaryotic cells. The parasitic kinetoplastids have a unique reliance on such processes, because their genome is organized into polycistronic transcription units in which adjacent genes are not coordinately regulated. Indeed, the number of RNA-binding proteins predicted to be encoded in the genome of kinetoplastids is unusually large, invoking the presence of unique RNA regulators dedicated to gene expression in these evolutionarily ancient organisms. Here, we report that a small CCCH zinc finger protein, TbZFP3, enhances development between life-cycle stages in Trypanosoma brucei. Moreover, we demonstrate that this protein interacts both with the translational machinery and with other small CCCH proteins previously implicated in trypanosome developmental control. Antibodies to this protein also co-immunoprecipitate EP procyclin mRNA and encode the major surface antigen of insect forms of T. brucei. Strikingly, although TbZFP3 is constitutively expressed, it exhibits developmentally regulated association with polyribosomes, and mutational analysis demonstrates that this association is essential for the expression of phenotype. TbZFP3 is therefore a novel regulator of developmental events in kinetoplastids that acts at the level of the post-transcriptional control of gene expression.
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Affiliation(s)
| | | | - Paul Craddy
- Institute of Immunology and Infection Research, School of Biological Sciences, Ashworth Laboratories, King’s Buildings, University of Edinburgh, West Mains Road, Edinburgh EH9 3JT, Scotland, United Kingdom
| | - Katelyn Fenn
- Institute of Immunology and Infection Research, School of Biological Sciences, Ashworth Laboratories, King’s Buildings, University of Edinburgh, West Mains Road, Edinburgh EH9 3JT, Scotland, United Kingdom
| | - Keith Matthews
- Institute of Immunology and Infection Research, School of Biological Sciences, Ashworth Laboratories, King’s Buildings, University of Edinburgh, West Mains Road, Edinburgh EH9 3JT, Scotland, United Kingdom
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13
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Caro F, Bercovich N, Atorrasagasti C, Levin MJ, Vázquez MP. Trypanosoma cruzi: analysis of the complete PUF RNA-binding protein family. Exp Parasitol 2006; 113:112-24. [PMID: 16460732 DOI: 10.1016/j.exppara.2005.12.015] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2005] [Revised: 12/20/2005] [Accepted: 12/21/2005] [Indexed: 10/25/2022]
Abstract
The members of the PUF family of RNA-binding proteins regulate the fate of mRNAs by binding to their 3'UTR sequence elements in eukaryotes. In trypanosomes, for which gene expression is polycistronic and controlled almost exclusively by post-transcriptional processes, PUF proteins could play a crucial role. We report here the complete analysis of the PUF protein family of Trypanosoma cruzi composed of 10 members. In silico analysis predicts the existence of at least three major groups within the T. cruzi family, based on their putative binding specificity. Using yeast three hybrid assays, we tested some of these predictions for TcPUF1, TcPUF3, TcPUF5, and TcPUF8 as representatives of these groups. Data mining of the T. cruzi genome led us to describe putative binding targets for the TcPUFs of the most conserved group, TcPUF1 and TcPUF2. The targets include genes for mitochondrial proteins and protein kinases. Finally, immunolocalization experiments showed that TcPUF1 is localized in multiple discrete foci in the cytoplasm supporting its proposed function.
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Affiliation(s)
- Florence Caro
- Laboratorio de Biología Molecular de la Enfermedad de Chagas--INGEBI--CONICET, Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, University of Buenos Aires, Argentina
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