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Bezerra MJR, Moura DMN, Freire ER, Holetz FB, Reis CRS, Monteiro TTS, Pinto ARS, Zhang N, Rezende AM, Pereira-Neves A, Figueiredo RCBQ, Clayton C, Field MC, Carrington M, de Melo Neto OP. Distinct mRNA and protein interactomes highlight functional differentiation of major eIF4F-like complexes from Trypanosoma brucei. Front Mol Biosci 2022; 9:971811. [PMID: 36275617 PMCID: PMC9585242 DOI: 10.3389/fmolb.2022.971811] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Accepted: 09/20/2022] [Indexed: 11/13/2022] Open
Abstract
Gene expression in pathogenic protozoans of the family Trypanosomatidae has several novel features, including multiple eIF4F-like complexes involved in protein synthesis. The eukaryotic eIF4F complex, formed mainly by eIF4E and eIF4G subunits, is responsible for the canonical selection of mRNAs required for the initiation of mRNA translation. The best-known complexes implicated in translation in trypanosomatids are based on two related pairs of eIF4E and eIF4G subunits (EIF4E3/EIF4G4 and EIF4E4/EIF4G3), whose functional distinctions remain to be fully described. Here, to define interactomes associated with both complexes in Trypanosoma brucei procyclic forms, we performed parallel immunoprecipitation experiments followed by identification of proteins co-precipitated with the four tagged eIF4E and eIF4G subunits. A number of different protein partners, including RNA binding proteins and helicases, specifically co-precipitate with each complex. Highlights with the EIF4E4/EIF4G3 pair include RBP23, PABP1, EIF4AI and the CRK1 kinase. Co-precipitated partners with the EIF4E3/EIF4G4 pair are more diverse and include DRBD2, PABP2 and different zinc-finger proteins and RNA helicases. EIF4E3/EIF4G4 are essential for viability and to better define their role, we further investigated their phenotypes after knockdown. Depletion of either EIF4E3/EIF4G4 mRNAs lead to aberrant morphology with a more direct impact on events associated with cytokinesis. We also sought to identify those mRNAs differentially associated with each complex through CLIP-seq with the two eIF4E subunits. Predominant among EIF4E4-bound transcripts are those encoding ribosomal proteins, absent from those found with EIF4E3, which are generally more diverse. RNAi mediated depletion of EIF4E4, which does not affect proliferation, does not lead to changes in mRNAs or proteins associated with EIF4E3, confirming a lack of redundancy and distinct roles for the two complexes.
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Affiliation(s)
- Maria J. R. Bezerra
- Aggeu Magalhães Institute, Oswaldo Cruz Foundation, Recife, Pernambuco, Brazil
- Department of Genetics, Federal University of Pernambuco, Recife, Pernambuco, Brazil
| | | | - Eden R. Freire
- Carlos Chagas Institute, Oswaldo Cruz Foundation, Curitiba, Pernambuco, Brazil
| | - Fabiola B. Holetz
- Carlos Chagas Institute, Oswaldo Cruz Foundation, Curitiba, Pernambuco, Brazil
| | | | | | - Adriana R. S. Pinto
- Aggeu Magalhães Institute, Oswaldo Cruz Foundation, Recife, Pernambuco, Brazil
| | - Ning Zhang
- School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Antonio M. Rezende
- Aggeu Magalhães Institute, Oswaldo Cruz Foundation, Recife, Pernambuco, Brazil
| | | | | | - Christine Clayton
- Heidelberg University Center for Molecular Biology, Heidelberg, Germany
| | - Mark C. Field
- School of Life Sciences, University of Dundee, Dundee, United Kingdom
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czechia
| | - Mark Carrington
- Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom
| | - Osvaldo P. de Melo Neto
- Aggeu Magalhães Institute, Oswaldo Cruz Foundation, Recife, Pernambuco, Brazil
- *Correspondence: Osvaldo P. de Melo Neto,
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2
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de Lima GB, de Lima Cavalcanti TYV, de Brito ANALM, de Assis LA, Andrade-Vieira RP, Freire ER, da Silva Assunção TR, de Souza Reis CR, Zanchin NIT, Guimarães BG, de-Melo-Neto OP. The translation initiation factor EIF4E5 from Leishmania: crystal structure and interacting partners. RNA Biol 2021; 18:2433-2449. [PMID: 33945405 DOI: 10.1080/15476286.2021.1918919] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
The mRNA cap-binding protein, eIF4E, mediates the recognition of the mRNA 5' end and, as part of the heterotrimeric eIF4F complex, facilitates the recruitment of the ribosomal subunits to initiate eukaryotic translation. Various regulatory events involving eIF4E and a second eIF4F subunit, eIF4G, are required for proper control of translation initiation. In pathogenic trypanosomatids, six eIF4Es and five eIF4Gs have been described, several forming different eIF4F-like complexes with yet unresolved roles. EIF4E5 is one of the least known of the trypanosomatid eIF4Es and has not been characterized in Leishmania species. Here, we used immunoprecipitation assays, combined with mass-spectrometry, to identify major EIF4E5 interacting proteins in L. infantum. A constitutively expressed, HA-tagged, EIF4E5 co-precipitated mainly with EIF4G1 and binding partners previously described in Trypanosoma brucei, EIF4G1-IP, RBP43 and the 14-3-3 proteins. In contrast, no clear co-precipitation with EIF4G2, also previously reported, was observed. EIF4E5 also co-precipitated with protein kinases, possibly associated with cell-cycle regulation, selected RNA binding proteins and histones. Phosphorylated residues were identified and mapped to the Leishmania-specific C-terminal end. Mutagenesis of the tryptophan residue (W53) postulated to mediate interactions with protein partners or of a neighbouring tryptophan conserved in Leishmania (W45) did not substantially impair the identified interactions. Finally, the crystal structure of Leishmania EIF4E5 evidences remarkable differences in the eIF4G interfacing region, when compared with human eIF4E-1 and with its Trypanosoma orthologue. Mapping of its C-terminal end near the cap-binding site also imply relevant differences in cap-binding function and/or regulation.
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Affiliation(s)
- Gustavo Barbosa de Lima
- Departamento de Microbiologia, Instituto Aggeu Magalhães, FIOCRUZ-PE, Av. Moraes Rego s/n, Recife-PE, Brazil
| | - Thaíse Yasmine Vasconcelos de Lima Cavalcanti
- Departamento de Microbiologia, Instituto Aggeu Magalhães, FIOCRUZ-PE, Av. Moraes Rego s/n, Recife-PE, Brazil.,Programa de Pós-Graduação em Genética, Universidade Federal de Pernambuco, Recife-PE, Brazil
| | - Adriana Neuman Albuquerque Lins Moura de Brito
- Departamento de Microbiologia, Instituto Aggeu Magalhães, FIOCRUZ-PE, Av. Moraes Rego s/n, Recife-PE, Brazil.,Programa de Pós-Graduação em Genética, Universidade Federal de Pernambuco, Recife-PE, Brazil
| | - Ludmilla Arruda de Assis
- Departamento de Microbiologia, Instituto Aggeu Magalhães, FIOCRUZ-PE, Av. Moraes Rego s/n, Recife-PE, Brazil
| | | | - Eden Ribeiro Freire
- Departamento de Microbiologia, Instituto Aggeu Magalhães, FIOCRUZ-PE, Av. Moraes Rego s/n, Recife-PE, Brazil.,Laboratório de Biologia Estrutural e Engenharia de Proteínas, Instituto Carlos Chagas, FIOCRUZ-PR, Curitiba-PR, Brazil
| | | | | | - Nilson Ivo Tonin Zanchin
- Laboratório de Biologia Estrutural e Engenharia de Proteínas, Instituto Carlos Chagas, FIOCRUZ-PR, Curitiba-PR, Brazil
| | - Beatriz Gomes Guimarães
- Laboratório de Biologia Estrutural e Engenharia de Proteínas, Instituto Carlos Chagas, FIOCRUZ-PR, Curitiba-PR, Brazil
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3
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Castro Machado F, Bittencourt-Cunha P, Malvezzi AM, Arico M, Radio S, Smircich P, Zoltner M, Field MC, Schenkman S. EIF2α phosphorylation is regulated in intracellular amastigotes for the generation of infective Trypanosoma cruzi trypomastigote forms. Cell Microbiol 2020; 22:e13243. [PMID: 32597009 DOI: 10.1111/cmi.13243] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Revised: 06/15/2020] [Accepted: 06/18/2020] [Indexed: 12/13/2022]
Abstract
Trypanosomatids regulate gene expression mainly at the post-transcriptional level through processing, exporting and stabilising mRNA and control of translation. In most eukaryotes, protein synthesis is regulated by phosphorylation of eukaryotic initiation factor 2 (eIF2) at serine 51. Phosphorylation halts overall translation by decreasing availability of initiator tRNAmet to form translating ribosomes. In trypanosomatids, the N-terminus of eIF2α is extended with threonine 169 the homologous phosphorylated residue. Here, we evaluated whether eIF2α phosphorylation varies during the Trypanosoma cruzi life cycle, the etiological agent of Chagas' disease. Total levels of eIF2α are diminished in infective and non-replicative trypomastigotes compared with proliferative forms from the intestine of the insect vector or amastigotes from mammalian cells, consistent with decreased protein synthesis reported in infective forms. eIF2α phosphorylation increases in proliferative intracellular forms prior to differentiation into trypomastigotes. Parasites overexpressing eIF2αT169A or with an endogenous CRISPR/Cas9-generated eIF2αT169A mutation were created and analysis revealed alterations to the proteome, largely unrelated to the presence of μORF in epimastigotes. eIF2αT169A mutant parasites produced fewer trypomastigotes with lower infectivity than wild type, with increased levels of sialylated mucins and oligomannose glycoproteins, and decreased galactofuranose epitopes and the surface protease GP63 on the cell surface. We conclude that eIF2α expression and phosphorylation levels affect proteins relevant for intracellular progression of T. cruzi.
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Affiliation(s)
- Fabricio Castro Machado
- Departmento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Paula Bittencourt-Cunha
- Departmento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Amaranta Muniz Malvezzi
- Departmento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Mirella Arico
- Departmento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Santiago Radio
- Department of Genomics, Instituto de Investigaciones Biológicas Clemente Estable, Ministerio de Educación y Cultura, Montevideo, Uruguay.,Laboratory of Molecular Interactions, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
| | - Pablo Smircich
- Department of Genomics, Instituto de Investigaciones Biológicas Clemente Estable, Ministerio de Educación y Cultura, Montevideo, Uruguay.,Laboratory of Molecular Interactions, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
| | - Martin Zoltner
- Drug Discovery and Evaluation, Centre for Research of Pathogenicity and Virulence of Parasites, Charles University, Prague, Czech Republic
| | - Mark C Field
- Division of Biological Chemistry and Drug Discovery, University of Dundee, Dundee, UK.,Institute of Parasitology, Czech Academy of Sciences, Prague, Czech Republic
| | - Sergio Schenkman
- Departmento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
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4
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An T, Liu Y, Gourguechon S, Wang CC, Li Z. CDK Phosphorylation of Translation Initiation Factors Couples Protein Translation with Cell-Cycle Transition. Cell Rep 2019; 25:3204-3214.e5. [PMID: 30540951 PMCID: PMC6350937 DOI: 10.1016/j.celrep.2018.11.063] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 10/18/2018] [Accepted: 11/15/2018] [Indexed: 01/17/2023] Open
Abstract
Protein translation in eukaryotes is cell-cycle dependent, with translation rates more robust in G1 phase of the cell cycle than in mitosis. However, whether the fundamental cell-cycle control machinery directly activates protein translation during the G1/S cell-cycle transition remains unknown. Using the early divergent eukaryote Trypanosoma brucei as a model organism, we report that the G1 cyclin-dependent kinase CRK1 phosphorylates two translation initiation factors, eIF4E4 and PABP1, to promote the G1/S cell-cycle transition and global protein translation. Phosphorylation of eIF4E4 by CRK1 enhances binding to the m7G cap structure and interaction with eIF4E4 and eIF4G3, and phosphorylation of PABP1 by CRK1 promotes association with the poly(A) sequence, self-interaction, and interaction with eIF4E4. These findings demonstrate that cyclin-dependent kinase-mediated regulation of translation initiation factors couples global protein translation with the G1/S cell-cycle transition. Protein translation is cell-cycle dependent, with more robust translation rates in the G1 phase of the cell cycle than in mitosis. An et al. show that the G1 cyclin-dependent kinase CRK1 phosphorylates translation initiation factors eIF4E4 and PABP1 to couple protein translation initiation with the G1/S cell-cycle transition.
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Affiliation(s)
- Tai An
- Department of Microbiology and Molecular Genetics, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Yi Liu
- Department of Microbiology and Molecular Genetics, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Stéphane Gourguechon
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Ching C Wang
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Ziyin Li
- Department of Microbiology and Molecular Genetics, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77030, USA.
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5
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Sharma R, Terrão MC, Castro FF, Breitling R, Faça V, Oliveira EB, Cruz AK. Insights on a putative aminoacyl-tRNA-protein transferase of Leishmania major. PLoS One 2018; 13:e0203369. [PMID: 30208112 PMCID: PMC6135404 DOI: 10.1371/journal.pone.0203369] [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: 02/15/2018] [Accepted: 08/20/2018] [Indexed: 11/29/2022] Open
Abstract
The N-end rule pathway leads to regulated proteolysis as an adaptive response to external stress and is ubiquitous from bacteria to mammals. In this study, we investigated a gene coding for a putative core enzyme of this post-translational regulatory pathway in Leishmania major, which may be crucial during cytodifferentiation and the environment adaptive responses of the parasite. Leucyl, phenylalanyl-tRNA protein transferase and arginyl-tRNA protein transferase are key components of this pathway in E. coli and eukaryotes, respectively. They catalyze the specific conjugation of leucine, phenylalanine or arginine to proteins containing exposed N-terminal amino acid residues, which are recognized by the machinery for the targeted proteolysis. Here, we characterized a conserved hypothetical protein coded by the LmjF.21.0725 gene in L. major. In silico analysis suggests that the LmjF.21.0725 protein is highly conserved among species of Leishmania and might belong to the Acyl CoA-N-acyltransferases (NAT) superfamily of proteins. Immunofluorescence cell imaging indicates that the cytosolic localization of the studied protein and the endogenous levels of the protein in promastigotes are barely detectable by western blotting assay. The knockout of the two alleles of LmjF.21.0725 by homologous recombination was only possible in the heterozygous transfectant expressing LmjF.21.0725 as a transgene from a plasmid. Moreover, the kinetics of loss of the plasmid in the absence of drug pressure suggests that maintenance of the gene is essential for promastigote survival. Here, evidence is provided that this putative aminoacyl tRNA-protein transferase is essential for parasite survival. The enzyme activity and corresponding post-translational regulatory pathway are yet to be investigated.
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Affiliation(s)
- Rohit Sharma
- Department of Cell and Molecular Biology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Monica Cristina Terrão
- Department of Cell and Molecular Biology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Felipe Freitas Castro
- Department of Cell and Molecular Biology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | | | - Vitor Faça
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Eduardo Brandt Oliveira
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Angela Kaysel Cruz
- Department of Cell and Molecular Biology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
- * E-mail:
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6
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Yu J, Marintchev A. Comparative sequence and structure analysis of eIF1A and eIF1AD. BMC STRUCTURAL BIOLOGY 2018; 18:11. [PMID: 30180896 PMCID: PMC6122471 DOI: 10.1186/s12900-018-0091-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Accepted: 08/24/2018] [Indexed: 11/10/2022]
Abstract
BACKGROUND Eukaryotic translation initiation factor 1A (eIF1A) is universally conserved in all organisms. It has multiple functions in translation initiation, including assembly of the ribosomal pre-initiation complexes, mRNA binding, scanning, and ribosomal subunit joining. eIF1A binds directly to the small ribosomal subunit, as well as to several other translation initiation factors. The structure of an eIF1A homolog, the eIF1A domain-containing protein (eIF1AD) was recently determined but its biological functions are unknown. Since eIF1AD has a known structure, as well as a homolog, whose structure and functions have been extensively studied, it is a very attractive target for sequence and structure analysis. RESULTS Structure/sequence analysis of eIF1AD found significant conservation in the surfaces corresponding to the ribosome-binding surfaces of its paralog eIF1A, including a nearly invariant surface-exposed tryptophan residue, which plays an important role in the interaction of eIF1A with the ribosome. These results indicate that eIF1AD may bind to the ribosome, similar to its paralog eIF1A, and could have roles in ribosome biogenenesis or regulation of translation. We identified conserved surfaces and sequence motifs in the folded domain as well as the C-terminal tail of eIF1AD, which are likely protein-protein interaction sites. The roles of these regions for eIF1AD function remain to be determined. We have also identified a set of trypanosomatid-specific surface determinants in eIF1A that could be a promising target for development of treatments against these parasites. CONCLUSIONS The results described here identify regions in eIF1A and eIF1AD that are likely to play major functional roles and are promising therapeutic targets. Our findings and hypotheses will promote new research and help elucidate the functions of eIF1AD.
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Affiliation(s)
- Jielin Yu
- Department of Physiology and Biophysics, Boston University School of Medicine, Boston, MA, USA
| | - Assen Marintchev
- Department of Physiology and Biophysics, Boston University School of Medicine, Boston, MA, USA.
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7
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de Melo Neto OP, da Costa Lima TDC, Merlo KC, Romão TP, Rocha PO, Assis LA, Nascimento LM, Xavier CC, Rezende AM, Reis CRS, Papadopoulou B. Phosphorylation and interactions associated with the control of the Leishmania Poly-A Binding Protein 1 (PABP1) function during translation initiation. RNA Biol 2018; 15:739-755. [PMID: 29569995 DOI: 10.1080/15476286.2018.1445958] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The Poly-A Binding Protein (PABP) is a conserved eukaryotic polypeptide involved in many aspects of mRNA metabolism. During translation initiation, PABP interacts with the translation initiation complex eIF4F and enhances the translation of polyadenylated mRNAs. Schematically, most PABPs can be divided into an N-terminal RNA-binding region, a non-conserved linker segment and the C-terminal MLLE domain. In pathogenic Leishmania protozoans, three PABP homologues have been identified, with the first one (PABP1) targeted by phosphorylation and shown to co-immunoprecipitate with an eIF4F-like complex (EIF4E4/EIF4G3) implicated in translation initiation. Here, PABP1 phosphorylation was shown to be linked to logarithmic cell growth, reminiscent of EIF4E4 phosphorylation, and coincides with polysomal association. Phosphorylation targets multiple serine-proline (SP) or threonine-proline (TP) residues within the PABP1 linker region. This is an essential protein, but phosphorylation is not needed for its association with polysomes or cell viability. Mutations which do impair PABP1 polysomal association and are required for viability do not prevent phosphorylation, although further mutations lead to a presumed inactive protein largely lacking phosphorylated isoforms. Co-immunoprecipitation experiments were carried out to investigate PABP1 function further, identifying several novel protein partners and the EIF4E4/EIF4G3 complex, but no other eIF4F-like complex or subunit. A novel, direct interaction between PABP1 and EIF4E4 was also investigated and found to be mediated by the PABP1 MLLE binding to PABP Interacting Motifs (PAM2) within the EIF4E4 N-terminus. The results shown here are consistent with phosphorylation of PABP1 being part of a novel pathway controlling its function and possibly translation in Leishmania.
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Affiliation(s)
| | | | - Kleison C Merlo
- a Instituto Aggeu Magalhães - FIOCRUZ , Recife , PE , Brazil
| | - Tatiany P Romão
- a Instituto Aggeu Magalhães - FIOCRUZ , Recife , PE , Brazil
| | | | - Ludmila A Assis
- a Instituto Aggeu Magalhães - FIOCRUZ , Recife , PE , Brazil
| | | | - Camila C Xavier
- a Instituto Aggeu Magalhães - FIOCRUZ , Recife , PE , Brazil
| | | | | | - Barbara Papadopoulou
- c CHU de Quebec Research Center and Department of Microbiology-Infectious Disease and Immunology , Laval University , Quebec , QC , Canada
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8
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Erben ED. High-throughput Methods for Dissection of Trypanosome Gene Regulatory Networks. Curr Genomics 2018; 19:78-86. [PMID: 29491736 PMCID: PMC5814965 DOI: 10.2174/1389202918666170815125336] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Revised: 12/22/2016] [Accepted: 02/03/2017] [Indexed: 12/24/2022] Open
Abstract
From synthesis to decay, mRNA associates with RNA-binding proteins (RBPs) establishing dynamic ribonucleoprotein particles (RNPs). Understanding the composition and function of RNPs is fundamental to understanding how eukaryotic mRNAs are controlled. This is especially relevant for trypanosomes and related kinetoplastid parasites, which mostly rely on post-transcriptional mechanisms to control gene expression. Crucial for trypanosome differentiation, development, or even response to heat shock, RBPs are known to be essential modulators of diverse molecular processes. The recent application of large-scale quantitative methods, such as Next-Generation Sequencing (NGS) and quantitative mass spectrometry, has revealed new exciting features about the parasite RNA-related metabolism. Novel proteins carrying RNA-binding activity, including many proteins without RNA-related ontology were discovered setting a necessary groundwork to get in insights into RNA biology. Conclusion: This review aims to give the reader an understanding of current trypanosome RNP research, highlighting the progress made using high-throughput approaches.
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Affiliation(s)
- Esteban D Erben
- Zentrum fur Molekulare Biologie der Universitet Heidelberg (ZMBH), Im Neuenheimer Feld 282, 69120Heidelberg, Germany
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9
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Garde E, Ramírez L, Corvo L, Solana JC, Martín ME, González VM, Gómez-Nieto C, Barral A, Barral-Netto M, Requena JM, Iborra S, Soto M. Analysis of the Antigenic and Prophylactic Properties of the Leishmania Translation Initiation Factors eIF2 and eIF2B in Natural and Experimental Leishmaniasis. Front Cell Infect Microbiol 2018; 8:112. [PMID: 29675401 PMCID: PMC5895769 DOI: 10.3389/fcimb.2018.00112] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Accepted: 03/21/2018] [Indexed: 02/05/2023] Open
Abstract
Different members of intracellular protein families are recognized by the immune system of the vertebrate host infected by parasites of the genus Leishmania. Here, we have analyzed the antigenic and immunogenic properties of the Leishmania eIF2 and eIF2B translation initiation factors. An in silico search in Leishmania infantum sequence databases allowed the identification of the genes encoding the α, β, and γ subunits and the α, β, and δ subunits of the putative Leishmania orthologs of the eukaryotic initiation factors F2 (LieIF2) or F2B (LieIF2B), respectively. The antigenicity of these factors was analyzed by ELISA using recombinant versions of the different subunits. Antibodies against the different LieIF2 and LieIF2B subunits were found in the sera from human and canine visceral leishmaniasis patients, and also in the sera from hamsters experimentally infected with L. infantum. In L. infantum (BALB/c) and Leishmania major (BALB/c or C57BL/6) challenged mice, a moderate humoral response against these protein factors was detected. Remarkably, these proteins elicited an IL-10 production by splenocytes derived from infected mice independently of the Leishmania species employed for experimental challenge. When DNA vaccines based on the expression of the LieIF2 or LieIF2B subunit encoding genes were administered in mice, an antigen-specific secretion of IFN-γ and IL-10 cytokines was observed. Furthermore, a partial protection against murine CL development due to L. major infection was generated in the vaccinated mice. Also, in this work we show that the LieIF2α subunit and the LieIF2Bβ and δ subunits have the capacity to stimulate IL-10 secretion by spleen cells from naïve mice. B-lymphocytes were identified as the major producers of this anti-inflammatory cytokine. Taking into account the data found in this study, it may be hypothesized that these proteins act as virulence factors implicated in the induction of humoral responses as well as in the production of the down-regulatory IL-10 cytokine, favoring a pathological outcome. Therefore, these proteins might be considered markers of disease.
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Affiliation(s)
- Esther Garde
- Departamento de Biología Molecular, Facultad de Ciencias, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas (CSIC)-Universidad Autónoma de Madrid (UAM), Madrid, Spain
| | - Laura Ramírez
- Departamento de Biología Molecular, Facultad de Ciencias, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas (CSIC)-Universidad Autónoma de Madrid (UAM), Madrid, Spain
| | - Laura Corvo
- Departamento de Biología Molecular, Facultad de Ciencias, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas (CSIC)-Universidad Autónoma de Madrid (UAM), Madrid, Spain
| | - José C. Solana
- Departamento de Biología Molecular, Facultad de Ciencias, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas (CSIC)-Universidad Autónoma de Madrid (UAM), Madrid, Spain
| | - M. Elena Martín
- Departamento de Bioquímica-Investigación, Hospital Ramón y Cajal, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
| | - Víctor M. González
- Departamento de Bioquímica-Investigación, Hospital Ramón y Cajal, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
| | - Carlos Gómez-Nieto
- Parasitology Unit, LeishmanCeres Laboratory, Veterinary Faculty, University of Extremadura, Cáceres, Spain
| | - Aldina Barral
- Centro de Pesquisas Gonçalo Moniz, Fundação Oswaldo Cruz-FIOCRUZ, Salvador, Brazil
| | - Manoel Barral-Netto
- Centro de Pesquisas Gonçalo Moniz, Fundação Oswaldo Cruz-FIOCRUZ, Salvador, Brazil
| | - José M. Requena
- Departamento de Biología Molecular, Facultad de Ciencias, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas (CSIC)-Universidad Autónoma de Madrid (UAM), Madrid, Spain
| | - Salvador Iborra
- Immunobiology of Inflammation Laboratory, Department of Vascular Biology and Inflammation, Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain
- Department of Immunology, School of Medicine, Universidad Complutense de Madrid, Madrid, Spain
- Health Research Institute (imas12), Ciudad Universitaria, Madrid, Spain
- *Correspondence: Salvador Iborra
| | - Manuel Soto
- Departamento de Biología Molecular, Facultad de Ciencias, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas (CSIC)-Universidad Autónoma de Madrid (UAM), Madrid, Spain
- Manuel Soto
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10
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Freire ER, Moura DMN, Bezerra MJR, Xavier CC, Morais-Sobral MC, Vashisht AA, Rezende AM, Wohlschlegel JA, Sturm NR, de Melo Neto OP, Campbell DA. Trypanosoma brucei EIF4E2 cap-binding protein binds a homolog of the histone-mRNA stem-loop-binding protein. Curr Genet 2017; 64:821-839. [DOI: 10.1007/s00294-017-0795-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Revised: 12/01/2017] [Accepted: 12/08/2017] [Indexed: 12/12/2022]
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11
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The Role of Cytoplasmic mRNA Cap-Binding Protein Complexes in Trypanosoma brucei and Other Trypanosomatids. Pathogens 2017; 6:pathogens6040055. [PMID: 29077018 PMCID: PMC5750579 DOI: 10.3390/pathogens6040055] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Revised: 10/21/2017] [Accepted: 10/22/2017] [Indexed: 11/16/2022] Open
Abstract
Trypanosomatid protozoa are unusual eukaryotes that are well known for having unusual ways of controlling their gene expression. The lack of a refined mode of transcriptional control in these organisms is compensated by several post-transcriptional control mechanisms, such as control of mRNA turnover and selection of mRNA for translation, that may modulate protein synthesis in response to several environmental conditions found in different hosts. In other eukaryotes, selection of mRNA for translation is mediated by the complex eIF4F, a heterotrimeric protein complex composed by the subunits eIF4E, eIF4G, and eIF4A, where the eIF4E binds to the 5'-cap structure of mature mRNAs. In this review, we present and discuss the characteristics of six trypanosomatid eIF4E homologs and their associated proteins that form multiple eIF4F complexes. The existence of multiple eIF4F complexes in trypanosomatids evokes exquisite mechanisms for differential mRNA recognition for translation.
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12
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Di Renzo MA, Laverrière M, Schenkman S, Wehrendt DP, Tellez-Iñón MT, Potenza M. Characterization of TcCYC6 from Trypanosoma cruzi, a gene with homology to mitotic cyclins. Parasitol Int 2016; 65:196-204. [DOI: 10.1016/j.parint.2015.12.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Revised: 12/14/2015] [Accepted: 12/16/2015] [Indexed: 11/30/2022]
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13
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Avila CCDC, Peacock L, Machado FC, Gibson W, Schenkman S, Carrington M, Castilho BA. Phosphorylation of eIF2α on Threonine 169 is not required for Trypanosoma brucei cell cycle arrest during differentiation. Mol Biochem Parasitol 2016; 205:16-21. [PMID: 26996431 PMCID: PMC4850487 DOI: 10.1016/j.molbiopara.2016.03.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Revised: 03/15/2016] [Accepted: 03/16/2016] [Indexed: 11/17/2022]
Abstract
Pleomorphic T. brucei expressing an eIF2α phosphorylation site mutant were made. The mutation did not prevent normal arrest and differentiation into stumpy forms. Mutants differentiate into procyclic forms in vitro and in tsetse flies.
The trypanosome life cycle consists of a series of developmental forms each adapted to an environment in the relevant insect and/or mammalian host. The differentiation process from the mammalian bloodstream form to the insect-midgut procyclic form in Trypanosoma brucei occurs in two steps in vivo. First proliferating ‘slender' bloodstream forms differentiate to non-dividing ‘stumpy' forms arrested in G1. Second, in response to environmental cues, stumpy bloodstream forms re-enter the cell cycle and start to proliferate as procyclic forms after a lag during which both cell morphology and gene expression are modified. Nearly all arrested cells have lower rates of protein synthesis when compared to the proliferating equivalent. In eukaryotes, one mechanism used to regulate the overall rate of protein synthesis involves phosphorylation of the alpha subunit of initiation factor eIF2 (eIF2α). The effect of eIF2α phosphorylation is to prevent the action of eIF2B, the guanine nucleotide exchange factor that activates eIF2 for the next rounds of initiation. To investigate the role of the phosphorylation of eIF2α in the life cycle of T. brucei, a cell line was made with a single eIF2α gene that contained the phosphorylation site, threonine 169, mutated to alanine. These cells were capable of differentiating from proliferating bloodstream form cells into arrested stumpy forms in mice and into procyclic forms in vitro and in tsetse flies. These results indicate that translation attenuation mediated by the phosphorylation of eIF2α on threonine 169 is not necessary for the cell cycle arrest associated with these differentiation processes.
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Affiliation(s)
- Carla Cristi D C Avila
- Department of Microbiology, Immunology and Parasitology, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brazil
| | - Lori Peacock
- Department of Clinical Veterinary Science, University of Bristol, Langford, Bristol BS40 5DU, UK; School of Biological Sciences, University of Bristol, Bristol BS8 1TQ, UK
| | - Fabricio Castro Machado
- Department of Microbiology, Immunology and Parasitology, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brazil
| | - Wendy Gibson
- School of Biological Sciences, University of Bristol, Bristol BS8 1TQ, UK
| | - Sergio Schenkman
- Department of Microbiology, Immunology and Parasitology, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brazil
| | - Mark Carrington
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1QW, UK.
| | - Beatriz A Castilho
- Department of Microbiology, Immunology and Parasitology, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brazil.
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14
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Lueong S, Merce C, Fischer B, Hoheisel JD, Erben ED. Gene expression regulatory networks in Trypanosoma brucei: insights into the role of the mRNA-binding proteome. Mol Microbiol 2016; 100:457-71. [PMID: 26784394 DOI: 10.1111/mmi.13328] [Citation(s) in RCA: 84] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/14/2016] [Indexed: 12/11/2022]
Abstract
Control of gene expression at the post-transcriptional level is essential in all organisms, and RNA-binding proteins play critical roles from mRNA synthesis to decay. To fully understand this process, it is necessary to identify the complete set of RNA-binding proteins and the functional consequences of the protein-mRNA interactions. Here, we provide an overview of the proteins that bind to mRNAs and their functions in the pathogenic bloodstream form of Trypanosoma brucei. We describe the production of a small collection of open-reading frames encoding proteins potentially involved in mRNA metabolism. With this ORFeome collection, we used tethering to screen for proteins that play a role in post-transcriptional control. A yeast two-hybrid screen showed that several of the discovered repressors interact with components of the CAF1/NOT1 deadenylation complex. To identify the RNA-binding proteins, we obtained the mRNA-bound proteome. We identified 155 high-confidence candidates, including many not previously annotated as RNA-binding proteins. Twenty seven of these proteins affected reporter expression in the tethering screen. Our study provides novel insights into the potential trypanosome mRNPs composition, architecture and function.
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Affiliation(s)
- Smiths Lueong
- Functional Genome Analysis, Deutsche Krebsforschungszentrum (DKFZ), Im Neuenheimer Feld 580, 69120 Heidelberg, Germany
| | - Clementine Merce
- Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH), DKFZ-ZMBH Alliance, Im Neuenheimer Feld 282
| | - Bernd Fischer
- Computational Genome Biology, Deutsches Krebsforschungszentrum (DKFZ), Im Neuenheimer Feld 580, 69120 Heidelberg
| | - Jörg D Hoheisel
- Functional Genome Analysis, Deutsche Krebsforschungszentrum (DKFZ), Im Neuenheimer Feld 580, 69120 Heidelberg, Germany
| | - Esteban D Erben
- Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH), DKFZ-ZMBH Alliance, Im Neuenheimer Feld 282
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15
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Moura DMN, Reis CRS, Xavier CC, da Costa Lima TD, Lima RP, Carrington M, de Melo Neto OP. Two related trypanosomatid eIF4G homologues have functional differences compatible with distinct roles during translation initiation. RNA Biol 2015; 12:305-19. [PMID: 25826663 DOI: 10.1080/15476286.2015.1017233] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
In higher eukaryotes, eIF4A, eIF4E and eIF4G homologues interact to enable mRNA recruitment to the ribosome. eIF4G acts as a scaffold for these interactions and also interacts with other proteins of the translational machinery. Trypanosomatid protozoa have multiple homologues of eIF4E and eIF4G and the precise function of each remains unclear. Here, 2 previously described eIF4G homologues, EIF4G3 and EIF4G4, were further investigated. In vitro, both homologues bound EIF4AI, but with different interaction properties. Binding to distinct eIF4Es was also confirmed; EIF4G3 bound EIF4E4 while EIF4G4 bound EIF4E3, both these interactions required similar binding motifs. EIF4G3, but not EIF4G4, interacted with PABP1, a poly-A binding protein homolog. Work in vivo with Trypanosoma brucei showed that both EIF4G3 and EIF4G4 are cytoplasmic and essential for viability. Depletion of EIF4G3 caused a rapid reduction in total translation while EIF4G4 depletion led to changes in morphology but no substantial inhibition of translation. Site-directed mutagenesis was used to disrupt interactions of the eIF4Gs with either eIF4E or eIF4A, causing different levels of growth inhibition. Overall the results show that only EIF4G3, with its cap binding partner EIF4E4, plays a major role in translational initiation.
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Affiliation(s)
- Danielle M N Moura
- a Centro de Pesquisas Aggeu Magalhães; Fundação Oswaldo Cruz ; Campus UFPE; Recife , PE , Brazil
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16
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de Melo Neto OP, da Costa Lima TDC, Xavier CC, Nascimento LM, Romão TP, Assis LA, Pereira MMC, Reis CRS, Papadopoulou B. The unique Leishmania EIF4E4 N-terminus is a target for multiple phosphorylation events and participates in critical interactions required for translation initiation. RNA Biol 2015; 12:1209-21. [PMID: 26338184 DOI: 10.1080/15476286.2015.1086865] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The eukaryotic initiation factor 4E (eIF4E) recognizes the mRNA cap structure and, together with eIF4G and eIF4A, form the eIF4F complex that regulates translation initiation in eukaryotes. In trypanosomatids, 2 eIF4E homologues (EIF4E3 and EIF4E4) have been shown to be part of eIF4F-like complexes with presumed roles in translation initiation. Both proteins possess unique N-terminal extensions, which can be targeted for phosphorylation. Here, we provide novel insights on the Leishmania infantum EIF4E4 function and regulation. We show that EIF4E4 is constitutively expressed throughout the parasite development but is preferentially phosphorylated in exponentially grown promastigote and amastigote life stages, hence correlating with high levels of translation. Phosphorylation targets multiple serine-proline or threonine-proline residues within the N-terminal extension of EIF4E4 but does not require binding to the EIF4E4's partner, EIF4G3, or to the cap structure. We also report that EIF4E4 interacts with PABP1 through 3 conserved boxes at the EIF4E4 N-terminus and that this interaction is a prerequisite for efficient EIF4E4 phosphorylation. EIF4E4 is essential for Leishmania growth and an EIF4E4 null mutant was only obtained in the presence of an ectopically provided wild type gene. Complementation for the loss of EIF4E4 with several EIF4E4 mutant proteins affecting either phosphorylation or binding to mRNA or to EIF4E4 protein partners revealed that, in contrast to other eukaryotes, only the EIF4E4-PABP1 interaction but neither the binding to EIF4G3 nor phosphorylation is essential for translation. These studies also demonstrated that the lack of both EIF4E4 phosphorylation and EIF4G3 binding leads to a non-functional protein. Altogether, these findings further highlight the unique features of the translation initiation process in trypanosomatid protozoa.
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Affiliation(s)
- Osvaldo P de Melo Neto
- a Departamento de Microbiologia ; Centro de Pesquisas Aggeu Magalhães-FIOCRUZ ; Recife , PE , Brazil
| | - Tamara D C da Costa Lima
- a Departamento de Microbiologia ; Centro de Pesquisas Aggeu Magalhães-FIOCRUZ ; Recife , PE , Brazil
| | - Camila C Xavier
- a Departamento de Microbiologia ; Centro de Pesquisas Aggeu Magalhães-FIOCRUZ ; Recife , PE , Brazil
| | - Larissa M Nascimento
- a Departamento de Microbiologia ; Centro de Pesquisas Aggeu Magalhães-FIOCRUZ ; Recife , PE , Brazil.,b CHU de Quebec Research Center and Department of Microbiology ; Infectious Disease and Immunology; Laval University ; Quebec, QC , Canada
| | - Tatiany P Romão
- a Departamento de Microbiologia ; Centro de Pesquisas Aggeu Magalhães-FIOCRUZ ; Recife , PE , Brazil
| | - Ludmila A Assis
- a Departamento de Microbiologia ; Centro de Pesquisas Aggeu Magalhães-FIOCRUZ ; Recife , PE , Brazil
| | - Mariana M C Pereira
- a Departamento de Microbiologia ; Centro de Pesquisas Aggeu Magalhães-FIOCRUZ ; Recife , PE , Brazil
| | - Christian R S Reis
- a Departamento de Microbiologia ; Centro de Pesquisas Aggeu Magalhães-FIOCRUZ ; Recife , PE , Brazil
| | - Barbara Papadopoulou
- b CHU de Quebec Research Center and Department of Microbiology ; Infectious Disease and Immunology; Laval University ; Quebec, QC , Canada
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17
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Cassola A, Romaniuk MA, Primrose D, Cervini G, D'Orso I, Frasch AC. Association of UBP1 to ribonucleoprotein complexes is regulated by interaction with the trypanosome ortholog of the human multifunctional P32 protein. Mol Microbiol 2015; 97:1079-96. [PMID: 26096620 DOI: 10.1111/mmi.13090] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/09/2015] [Indexed: 12/30/2022]
Abstract
Regulation of gene expression in trypanosomatid parasitic protozoa is mainly achieved posttranscriptionally. RNA-binding proteins (RBPs) associate to 3' untranslated regions in mRNAs through dedicated domains such as the RNA recognition motif (RRM). Trypanosoma cruzi UBP1 (TcUBP1) is an RRM-type RBP involved in stabilization/degradation of mRNAs. TcUBP1 uses its RRM to associate with cytoplasmic mRNA and to mRNA granules under starvation stress. Here, we show that under starvation stress, TcUBP1 is tightly associated with condensed cytoplasmic mRNA granules. Conversely, under high nutrient/low density-growing conditions, TcUBP1 ribonucleoprotein (RNP) complexes are lax and permeable to mRNA degradation and disassembly. After dissociating from mRNA, TcUBP1 can be phosphorylated only in unstressed parasites. We have identified TcP22, the ortholog of mammalian P32/C1QBP, as an interactor of TcUBP1 RRM. Overexpression of TcP22 decreased the number of TcUBP1 granules in starved parasites in vivo. Endogenous TcUBP1 RNP complexes could be dissociated in vitro by addition of recombinant TcP22, a condition stimulating TcUBP1 phosphorylation. Biochemical and in silico analysis revealed that TcP22 interacts with the RNA-binding surface of TcUBP1 RRM. We propose a model for the decondensation of TcUBP1 RNP complexes in T. cruzi through direct interaction with TcP22 and phosphorylation.
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Affiliation(s)
- Alejandro Cassola
- Instituto de Investigaciones Biotecnológicas-Instituto Tecnológico de Chascomús, UNSAM-CONICET, Buenos Aires, Argentina
| | - María Albertina Romaniuk
- Instituto de Investigaciones Biotecnológicas-Instituto Tecnológico de Chascomús, UNSAM-CONICET, Buenos Aires, Argentina
| | - Debora Primrose
- Instituto de Investigaciones Biotecnológicas-Instituto Tecnológico de Chascomús, UNSAM-CONICET, Buenos Aires, Argentina
| | - Gabriela Cervini
- Instituto de Investigaciones Biotecnológicas-Instituto Tecnológico de Chascomús, UNSAM-CONICET, Buenos Aires, Argentina
| | - Iván D'Orso
- Instituto de Investigaciones Biotecnológicas-Instituto Tecnológico de Chascomús, UNSAM-CONICET, Buenos Aires, Argentina
| | - Alberto Carlos Frasch
- Instituto de Investigaciones Biotecnológicas-Instituto Tecnológico de Chascomús, UNSAM-CONICET, Buenos Aires, Argentina
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18
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Jha BA, Gazestani VH, Yip CW, Salavati R. The DRBD13 RNA binding protein is involved in the insect-stage differentiation process of Trypanosoma brucei. FEBS Lett 2015; 589:1966-74. [PMID: 26028502 DOI: 10.1016/j.febslet.2015.05.036] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2015] [Revised: 04/21/2015] [Accepted: 05/20/2015] [Indexed: 11/25/2022]
Abstract
DRBD13 RNA-binding protein (RBP) regulates the abundance of AU-rich element (ARE)-containing transcripts in trypanosomes. Here we show that DRBD13 regulates RBP6, the developmentally critical protein in trypanosomatids. We also show DRBD13-specific regulation of transcripts encoding cell surface coat proteins including GPEET2, variable surface glycoprotein (VSG) and invariant surface glycoprotein (ISG). Accordingly, alteration in DRBD13 levels leads to changes in the target mRNA abundance and parasite morphology. The high consistency of the observed phenotype with known cell membrane exchanges that occur during progression of T. brucei through the insect stage of its life cycle suggests that DRBD13 is an important regulator in this largely unknown developmental process.
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Affiliation(s)
- Bhaskar Anand Jha
- Institute of Parasitology, McGill University, 21,111 Lakeshore Road, Ste. Anne de Bellevue, Quebec H9X3V9, Canada
| | - Vahid H Gazestani
- Institute of Parasitology, McGill University, 21,111 Lakeshore Road, Ste. Anne de Bellevue, Quebec H9X3V9, Canada
| | - Chun Wai Yip
- Institute of Parasitology, McGill University, 21,111 Lakeshore Road, Ste. Anne de Bellevue, Quebec H9X3V9, Canada
| | - Reza Salavati
- Institute of Parasitology, McGill University, 21,111 Lakeshore Road, Ste. Anne de Bellevue, Quebec H9X3V9, Canada.
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19
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de Almeida-Bizzo JH, Alves LR, Castro FF, Garcia JBF, Goldenberg S, Cruz AK. Characterization of the pattern of ribosomal protein L19 production during the lifecycle of Leishmania spp. Exp Parasitol 2014; 147:60-6. [DOI: 10.1016/j.exppara.2014.08.015] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2013] [Revised: 08/16/2014] [Accepted: 08/26/2014] [Indexed: 12/11/2022]
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