1
|
Mandell MA, Beatty WL, Beverley SM. Quantitative single-cell analysis of Leishmania major amastigote differentiation demonstrates variably extended expression of the lipophosphoglycan (LPG) virulence factor in different host cell types. PLoS Negl Trop Dis 2022; 16:e0010893. [PMID: 36302046 PMCID: PMC9642900 DOI: 10.1371/journal.pntd.0010893] [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: 09/11/2022] [Revised: 11/08/2022] [Accepted: 10/14/2022] [Indexed: 11/07/2022] Open
Abstract
Immediately following their deposition into the mammalian host by an infected sand fly vector, Leishmania parasites encounter and are engulfed by a variety of cell types. From there, parasites may transit to other cell types, primarily macrophages or dendritic cells, where they replicate and induce pathology. During this time, Leishmania cells undergo a dramatic transformation from the motile non-replicating metacyclic stage to the non-motile replicative amastigote stage, a differentiative process that can be termed amastigogenesis. To follow this at the single cell level, we identified a suite of experimental 'landmarks' delineating different stages of amastigogenesis qualitatively or quantitatively, including new uses of amastigote-specific markers that showed interesting cellular localizations at the anterior or posterior ends. We compared amastigogenesis in synchronous infections of peritoneal and bone-marrow derived macrophages (PEM, BMM) or dendritic cells (BMDC). Overall, the marker suite expression showed an orderly transition post-infection with similar kinetics between host cell types, with the emergence of several amastigote traits within 12 hours, followed by parasite replication after 24 hours, with parasites in BMM or BMDC initiating DNA replication more slowly. Lipophosphoglycan (LPG) is a Leishmania virulence factor that facilitates metacyclic establishment in host cells but declines in amastigotes. Whereas LPG expression was lost by parasites within PEM by 48 hours, >40% of the parasites infecting BMM or BMDC retained metacyclic-level LPG expression at 72 hr. Thus L. major may prolong LPG expression in different intracellular environments, thereby extending its efficacy in promoting infectivity in situ and during cell-to-cell transfer of parasites expressing this key virulence factor.
Collapse
Affiliation(s)
- Michael A. Mandell
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Current address: Department of Molecular Genetics and Microbiology, University of New Mexico Health Sciences Center, Albuquerque, New Mexico, United States of America
| | - Wandy L. Beatty
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Stephen M. Beverley
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| |
Collapse
|
2
|
Cortazzo da Silva L, Aoki JI, Floeter-Winter LM. Finding Correlations Between mRNA and Protein Levels in Leishmania Development: Is There a Discrepancy? Front Cell Infect Microbiol 2022; 12:852902. [PMID: 35903202 PMCID: PMC9318571 DOI: 10.3389/fcimb.2022.852902] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Accepted: 05/02/2022] [Indexed: 12/02/2022] Open
Abstract
Multiple genes and proteins have been identified as differentially expressed in the stages of the Leishmania life cycle. The differentiation processes are implicated in specific transcriptional and proteomic adjustments driven by gene expression regulation mechanisms. Leishmania parasites lack gene-specific transcriptional control, and gene expression regulation mostly depends on posttranscriptional mechanisms. Due to the lack of transcriptional regulation, criticism regarding the relevance of transcript quantification as a possible and efficient prediction of protein levels is recurrent in studies that use transcriptomic information. The advent of high-throughput technologies has improved the analysis of genomes, transcriptomes and proteomes for different organisms under several conditions. Nevertheless, defining the correlation between transcriptional and proteomic profiles requires arduous and expensive work and remains a challenge in Leishmania. In this review, we analyze transcriptomic and proteomic data for several Leishmania species in two different stages of the parasite life cycle: metacyclogenesis and amastigogenesis (amastigote differentiation). We found a correlation between mRNA and protein levels of 60.9% and 69.8% for metacyclogenesis and amastigogenesis, respectively; showing that majority mRNA and protein levels increase or decrease concomitantly. Among the analyzed genes that did not present correlation indicate that transcriptomic data should be carefully interpreted as protein expression. We also discuss possible explanations and mechanisms involved for this lack of correlation.
Collapse
|
3
|
Ashrafmansouri M, Amiri‐Dashatan N, Ahmadi N, Rezaei‐Tavirani M, SeyyedTabaei S, Haghighi A. Quantitative proteomic analysis to determine differentially expressed proteins in axenic amastigotes of
Leishmania tropica
and
Leishmania major. IUBMB Life 2020; 72:1715-1724. [DOI: 10.1002/iub.2300] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Revised: 03/25/2020] [Accepted: 04/17/2020] [Indexed: 12/12/2022]
Affiliation(s)
- Marzieh Ashrafmansouri
- Department of Medical Parasitology and Mycology, Student Research Committee, School of MedicineShahid Beheshti University of Medical Sciences Tehran Iran
- Diagnostic Laboratory Sciences and Technology Research Center, Faculty of Paramedical SciencesShiraz University of Medical Sciences Shiraz Iran
| | - Nasrin Amiri‐Dashatan
- Proteomics Research Center, Faculty of Paramedical SciencesShahid Beheshti University of Medical Sciences Tehran Iran
| | - Nayebali Ahmadi
- Proteomics Research Center, Faculty of Paramedical SciencesShahid Beheshti University of Medical Sciences Tehran Iran
| | - Mostafa Rezaei‐Tavirani
- Proteomics Research Center, Faculty of Paramedical SciencesShahid Beheshti University of Medical Sciences Tehran Iran
| | - Seyyedjavad SeyyedTabaei
- Department of Medical Parasitology and Mycology, School of MedicineShahid Beheshti University of Medical Sciences Tehran Iran
| | - Ali Haghighi
- Department of Medical Parasitology and Mycology, School of MedicineShahid Beheshti University of Medical Sciences Tehran Iran
| |
Collapse
|
4
|
Evaluation of the Immunoprotective Potential of Recombinant Paraflagellar Rod Proteins of Trypanosoma evansi in Mice. Vaccines (Basel) 2020; 8:vaccines8010084. [PMID: 32059486 PMCID: PMC7157580 DOI: 10.3390/vaccines8010084] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Revised: 01/24/2020] [Accepted: 01/27/2020] [Indexed: 12/15/2022] Open
Abstract
Trypanosomosis, caused by Trypanosoma evansi, is an economically significant disease of livestock. Systematic antigenic variation by the parasite has undermined prospects for the development of a protective vaccine that targets the immunodominant surface antigens, encouraging exploration of alternatives. The paraflagellar rod (PFR), constituent proteins of the flagellum, are prominent non-variable vaccine candidates for T. evansi owing to their strategic location. Two major PFR constituent proteins, PFR1 (1770bp) and PFR2 (1800bp), were expressed using Escherichia coli. Swiss albino mice were immunized with the purified recombinant TePFR1 (89KDa) and TePFR2 (88KDa) proteins, as well as with the mix of the combined proteins at equimolar concentrations, and subsequently challenged with virulent T. evansi. The PFR-specific humoral response was assessed by ELISA. Cytometric bead-based assay was used to measure the cytokine response and flow cytometry for quantification of the cytokines. The recombinant TePFR proteins induced specific humoral responses in mice, including IgG1 followed by IgG2a and IgG2b. A balanced cytokine response induced by rTePFR 1 and 2 protein vaccination associated with extended survival and improved control of parasitemia following lethal challenge. The observation confirms the immunoprophylactic potential of the covert antigens of T. evansi.
Collapse
|
5
|
Untranslated regions of mRNA and their role in regulation of gene expression in protozoan parasites. J Biosci 2017; 42:189-207. [PMID: 28229978 DOI: 10.1007/s12038-016-9660-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Protozoan parasites are one of the oldest living entities in this world that throughout their existence have shown excellent resilience to the odds of survival and have adapted beautifully to ever changing rigors of the environment. In view of the dynamic environment encountered by them throughout their life cycle, and in establishing pathogenesis, it is unsurprising that modulation of gene expression plays a fundamental role in their survival. In higher eukaryotes, untranslated regions (UTRs) of transcripts are one of the crucial regulators of gene expression (influencing mRNA stability and translation efficiency). Parasitic protozoan genome studies have led to the characterization (in silico, in vitro and in vivo) of a large number of their genes. Comparison of higher eukaryotic UTRs with parasitic protozoan UTRs reveals the existence of several similar and dissimilar facets of the UTRs. This review focuses on the elements of UTRs of medically important protozoan parasites and their regulatory role in gene expression. Such information may be useful to researchers in designing gene targeting strategies linked with perturbation of host-parasite relationships leading to control of specific parasites.
Collapse
|
6
|
Stiles JK, Hicock PI, Shah PH, Meade JC. Genomic organization, transcription, splicing and gene regulation inLeishmania. ANNALS OF TROPICAL MEDICINE AND PARASITOLOGY 2016. [DOI: 10.1080/00034983.1999.11813485] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
|
7
|
Maharana BR, Tewari AK, Singh V. An overview on kinetoplastid paraflagellar rod. J Parasit Dis 2015; 39:589-95. [PMID: 26688619 PMCID: PMC4675581 DOI: 10.1007/s12639-014-0422-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2013] [Accepted: 01/13/2014] [Indexed: 01/23/2023] Open
Abstract
Kinetoplastids, the evolutionary ancient organisms exhibit a rich and diverse biology which epitomizes many of the fascinating topics of recent interest and study. These organisms possess a multifunctional organelle, the flagellum containing a canonical 9 + 2 axoneme which is involved in vital roles, viz. parasite cell division, morphogenesis, motility and immune evasion. Since Antony Van Leeuwenhoek's innovative explanation of 'little legs' helping the movements of microbes in 1975, this biological nanomachine has captured the thoughts of scientists. The core structure of kinetoplastid flagellum is embroidered with a range of extra-axonemal structures such as paraflagellar rod (PFR), a large lattice like structure which extends alongside the axoneme from the flagellar pocket to the flagellar tip. The coding sequences for significant components of PFR are highly conserved throughout the Kinetoplastida and Euglenida. The high order organization and restricted evolutionary distribution of the PFR components and structure makes the PFR a particularly valuable therapeutic and prophylactic target. This review focuses on the recent developments in identification of ultra structural components of PFR in order to understand the function of this intriguing organelle and devising strategies for therapeutic interventions.
Collapse
Affiliation(s)
- B. R. Maharana
- />Department of Veterinary Parasitology, College of Veterinary Science and Animal Husbandry, Junagadh Agricultural University, Junagadh, 362001 Gujarat India
| | - A. K. Tewari
- />Division of Veterinary Parasitology, Indian Veterinary Research Institute, Izatnagar, Bareilly, 243122 Uttar Pradesh India
| | - Veer Singh
- />Department of Veterinary Parasitology, College of Veterinary Science and Animal Husbandry, Sardar Krushinagar Dantiwada Agricultural University, Sardarkrushinagar, 3855006 Gujarat India
| |
Collapse
|
8
|
Fiebig M, Kelly S, Gluenz E. Comparative Life Cycle Transcriptomics Revises Leishmania mexicana Genome Annotation and Links a Chromosome Duplication with Parasitism of Vertebrates. PLoS Pathog 2015; 11:e1005186. [PMID: 26452044 PMCID: PMC4599935 DOI: 10.1371/journal.ppat.1005186] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Accepted: 09/03/2015] [Indexed: 02/07/2023] Open
Abstract
Leishmania spp. are protozoan parasites that have two principal life cycle stages: the motile promastigote forms that live in the alimentary tract of the sandfly and the amastigote forms, which are adapted to survive and replicate in the harsh conditions of the phagolysosome of mammalian macrophages. Here, we used Illumina sequencing of poly-A selected RNA to characterise and compare the transcriptomes of L. mexicana promastigotes, axenic amastigotes and intracellular amastigotes. These data allowed the production of the first transcriptome evidence-based annotation of gene models for this species, including genome-wide mapping of trans-splice sites and poly-A addition sites. The revised genome annotation encompassed 9,169 protein-coding genes including 936 novel genes as well as modifications to previously existing gene models. Comparative analysis of gene expression across promastigote and amastigote forms revealed that 3,832 genes are differentially expressed between promastigotes and intracellular amastigotes. A large proportion of genes that were downregulated during differentiation to amastigotes were associated with the function of the motile flagellum. In contrast, those genes that were upregulated included cell surface proteins, transporters, peptidases and many uncharacterized genes, including 293 of the 936 novel genes. Genome-wide distribution analysis of the differentially expressed genes revealed that the tetraploid chromosome 30 is highly enriched for genes that were upregulated in amastigotes, providing the first evidence of a link between this whole chromosome duplication event and adaptation to the vertebrate host in this group. Peptide evidence for 42 proteins encoded by novel transcripts supports the idea of an as yet uncharacterised set of small proteins in Leishmania spp. with possible implications for host-pathogen interactions.
Collapse
Affiliation(s)
- Michael Fiebig
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford, United Kingdom
| | - Steven Kelly
- Department of Plant Sciences, University of Oxford, South Parks Road, Oxford, United Kingdom
- * E-mail: (SK); (EG)
| | - Eva Gluenz
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford, United Kingdom
- * E-mail: (SK); (EG)
| |
Collapse
|
9
|
Magalhães RDM, Duarte MC, Mattos EC, Martins VT, Lage PS, Chávez-Fumagalli MA, Lage DP, Menezes-Souza D, Régis WCB, Manso Alves MJ, Soto M, Tavares CAP, Nagen RAP, Coelho EAF. Identification of differentially expressed proteins from Leishmania amazonensis associated with the loss of virulence of the parasites. PLoS Negl Trop Dis 2014; 8:e2764. [PMID: 24699271 PMCID: PMC3974679 DOI: 10.1371/journal.pntd.0002764] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2013] [Accepted: 02/16/2014] [Indexed: 11/18/2022] Open
Abstract
Background The present study analyzed whether or not the in vitro cultivation for long periods of time of pre-isolated Leishmania amazonensis from lesions of chronically infected BALB/c mice was able to interfere in the parasites' infectivity using in vivo and in vitro experiments. In addition, the proteins that presented a significant decrease or increase in their protein expression content were identified applying a proteomic approach. Methodology/Principal Findings Parasites were cultured in vitro for 150 days. Aliquots were collected on the day 0 of culture (R0), as well as after ten (R10; 50 days of culture), twenty (R20; 100 days of culture), and thirty (R30; 150 days of culture) passages, and were used to analyze the parasites' in vitro and in vivo infectivity, as well as to perform the proteomic approach. Approximately 837, 967, 935, and 872 spots were found in 2-DE gels prepared from R0, R10, R20, and R30 samples, respectively. A total of 37 spots presented a significant decrease in their intensity of expression, whereas a significant increase in protein content during cultivation could be observed for 19 proteins (both cases >2.0 folds). Some of these identified proteins can be described, such as diagnosis and/or vaccine candidates, while others are involved in the infectivity of Leishmania. It is interesting to note that six proteins, considered hypothetical in Leishmania, showed a significant decrease in their expression and were also identified. Conclusions/Significance The present study contributes to the understanding that the cultivation of parasites over long periods of time may well be related to the possible loss of infectivity of L. amazonensis. The identified proteins that presented a significant decrease in their expression during cultivation, including the hypothetical, may also be related to this loss of parasites' infectivity, and applied in future studies, including vaccine candidates and/or immunotherapeutic targets against leishmaniasis. Leishmania amazonensis can induce a diversity of clinical manifestations in mammal hosts, including tegumentary and visceral leishmaniasis. The present study evaluated the variation of infectivity of L. amazonensis, which was pre-isolated from lesions of chronically infected mice and in vitro cultured for 150 days, in turn connecting these results with the profile of parasite protein expression using a proteomic approach. Parasites were recovered after the first passage, as well as after 50, 100, and 150 days of axenic cultures, and were subsequently evaluated. A total of 37 proteins presented a significant decrease, whereas 19 proteins presented a significant increase in their protein expression content in the assays (both cases >2.0 fold). Some of the identified proteins have been reported in prior literature, including diagnosis and/or vaccine candidates for leishmaniasis, while others proved to be involved in the infectivity of Leishmania. It is interesting to note that proteins related to the parasites' metabolism were also the majority of the proteins identified in the old cultures of L. amazonensis, suggesting a possible relation between the metabolic state of parasites and their possible loss of infectivity. In conclusion, the proteins identified in this study represent a contribution to the discovery of new vaccine candidates and/or immunotherapeutic targets against leishmaniasis.
Collapse
Affiliation(s)
- Rubens D. M. Magalhães
- Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Mariana C. Duarte
- Programa de Pós-Graduação em Ciências Saúde: Infectologia e Medicina Tropical, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Eliciane C. Mattos
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, São Paulo, Brazil
| | - Vivian T. Martins
- Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Paula S. Lage
- Programa de Pós-Graduação em Ciências Saúde: Infectologia e Medicina Tropical, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Miguel A. Chávez-Fumagalli
- Programa de Pós-Graduação em Ciências Saúde: Infectologia e Medicina Tropical, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Daniela P. Lage
- Departamento de Patologia Clínica, COLTEC, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Daniel Menezes-Souza
- Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Wiliam C. B. Régis
- Departamento de Bioquímica, PUC Minas, Belo Horizonte, Minas Gerais, Brazil
| | - Maria J. Manso Alves
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, São Paulo, Brazil
| | - Manuel Soto
- Centro de Biología Molecular Severo Ochoa (CSIC-UAM), Departamento de Biología Molecular, Universidad Autónoma de Madrid, Madrid, Spain
| | - Carlos A. P. Tavares
- Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Ronaldo A. P. Nagen
- Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Eduardo A. F. Coelho
- Programa de Pós-Graduação em Ciências Saúde: Infectologia e Medicina Tropical, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
- Departamento de Patologia Clínica, COLTEC, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
- * E-mail:
| |
Collapse
|
10
|
Lefebvre M, Tetaud E, Thonnus M, Salin B, Boissier F, Blancard C, Sauvanet C, Metzler C, Espiau B, Sahin A, Merlin G. LdFlabarin, a new BAR domain membrane protein of Leishmania flagellum. PLoS One 2013; 8:e76380. [PMID: 24086735 PMCID: PMC3785460 DOI: 10.1371/journal.pone.0076380] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2013] [Accepted: 08/23/2013] [Indexed: 11/18/2022] Open
Abstract
During the Leishmania life cycle, the flagellum undergoes successive assembly and disassembly of hundreds of proteins. Understanding these processes necessitates the study of individual components. Here, we investigated LdFlabarin, an uncharacterized L. donovani flagellar protein. The gene is conserved within the Leishmania genus and orthologous genes only exist in the Trypanosoma genus. LdFlabarin associates with the flagellar plasma membrane, extending from the base to the tip of the flagellum as a helicoidal structure. Site-directed mutagenesis, deletions and chimera constructs showed that LdFlabarin flagellar addressing necessitates three determinants: an N-terminal potential acylation site and a central BAR domain for membrane targeting and the C-terminal domain for flagellar specificity. In vitro, the protein spontaneously associates with liposomes, triggering tubule formation, which suggests a structural/morphogenetic function. LdFlabarin is the first characterized Leishmania BAR domain protein, and the first flagellum-specific BAR domain protein.
Collapse
Affiliation(s)
- Michèle Lefebvre
- CNRS UMR 5290, Montpellier, France
- Université Montpellier 1, Montpellier, France
- Centre Hospitalier Universitaire La Colombière, Montpellier, France
- IRD 224, Montpellier, France
| | - Emmanuel Tetaud
- CNRS UMR 5095, Institut de Biochimie Génétique et Cellulaire, Bordeaux, France
- Université Bordeaux Segalen, Bordeaux, France
| | - Magali Thonnus
- CNRS UMR 5234, Bordeaux, France
- Université Bordeaux Segalen, Bordeaux, France
| | - Bénédicte Salin
- CNRS UMR 5095, Institut de Biochimie Génétique et Cellulaire, Bordeaux, France
- Université Bordeaux Segalen, Bordeaux, France
| | - Fanny Boissier
- CNRS UMR 5095, Institut de Biochimie Génétique et Cellulaire, Bordeaux, France
- Université Bordeaux Segalen, Bordeaux, France
| | - Corinne Blancard
- CNRS UMR 5095, Institut de Biochimie Génétique et Cellulaire, Bordeaux, France
- Université Bordeaux Segalen, Bordeaux, France
| | - Cécile Sauvanet
- CNRS UMR 5095, Institut de Biochimie Génétique et Cellulaire, Bordeaux, France
- Université Bordeaux Segalen, Bordeaux, France
| | | | - Benoît Espiau
- CNRS-EPHE USR 3278, Papetoai, Moorea, Polynésie Française
| | - Annelise Sahin
- CNRS UMR 5234, Bordeaux, France
- Université Bordeaux Segalen, Bordeaux, France
| | - Gilles Merlin
- CNRS UMR 5290, Montpellier, France
- Université Montpellier 1, Montpellier, France
- Centre Hospitalier Universitaire La Colombière, Montpellier, France
- IRD 224, Montpellier, France
- * E-mail:
| |
Collapse
|
11
|
Lynn MA, Marr AK, McMaster WR. Differential quantitative proteomic profiling of Leishmania infantum and Leishmania mexicana density gradient separated membranous fractions. J Proteomics 2013; 82:179-92. [PMID: 23466312 DOI: 10.1016/j.jprot.2013.02.010] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Revised: 02/08/2013] [Accepted: 02/09/2013] [Indexed: 12/22/2022]
Abstract
UNLABELLED Leishmaniasis, caused by infection with Leishmania, is a major public health concern affecting more than 20million people globally. Leishmania has a digenetic lifecycle consisting of an extracellular flagellated promastigote, adapted to live in the mid-gut of the sand fly host and an aflagellated intracellular amastigote that resides within the macrophage of the mammalian host. Leishmania mexicana and Leishmania infantum are causative agents of cutaneous and visceral leishmaniasis, respectively. Membrane proteins play a pivotal role in host-pathogen interactions and in regulatory pathways. As the genome of Leishmania is essentially constitutively expressed, regulation of protein expression during differentiation occurs post-transcriptionally and/or post-translationally. Quantitative mass spectrometry using iTRAQ labeling identified differences in the proteomes of density gradient separated membranous fractions of promastigote and amastigote life-stages. We identified 189 L. infantum and 107 L. mexicana non-redundant proteins of which 20-40% showed differential expression levels between promastigote and amastigote lifecycle stages. Differentially expressed proteins mapped to several pathways including cell motility, metabolism, and infectivity as well as virulence factors such as eEF-1α, amastin and leishmanolysin (GP63). Western blot analysis validated iTRAQ quantitation for leishmanolysin. Focusing on differentially expressed proteins essential for pathogenesis, may ultimately lead to the identification of novel potential therapeutic targets. BIOLOGICAL SIGNIFICANCE Leishmania, protozoan parasites of the Trypanosomatidae family, are the causative agents of leishmaniasis that represents a major public health concern affecting more than 20million people globally Membrane associated proteins play a pivotal role in host-pathogen interactions and in regulatory pathways. Quantitative proteomic analysis of the membranous fractions from L. mexicana and L. infantum (causative agents of cutaneous and visceral leishmaniasis, respectively) identified a number of proteins that may have important stage-specific functions in either the sand fly or mammalian host. The function of these proteins includes roles in virulence, as well as differences in metabolic process between life stages. Many of the proteins identified may act as virulence factors playing significant roles in parasite invasion, host-parasite interaction or parasite survival and thus may have therapeutic potential as drug target candidates.
Collapse
Affiliation(s)
- Miriam A Lynn
- Infection and Immunity Research Centre, Vancouver Coastal Health Research Institute, 2660 Oak Street, Vancouver, B.C., V6H 3Z6, Canada
| | | | | |
Collapse
|
12
|
Whole-genome comparative RNA expression profiling of axenic and intracellular amastigote forms of Leishmania infantum. Mol Biochem Parasitol 2009; 165:32-47. [DOI: 10.1016/j.molbiopara.2008.12.012] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2008] [Revised: 12/13/2008] [Accepted: 12/23/2008] [Indexed: 11/19/2022]
|
13
|
Abdille MH, Li SY, Ding J, Suo X. Trypanosoma evansi: Paraflagellar rod protein 1 and 2 are similar but lack common B cell epitopes. Exp Parasitol 2008; 120:411-6. [PMID: 18789932 DOI: 10.1016/j.exppara.2008.08.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2008] [Revised: 07/24/2008] [Accepted: 08/12/2008] [Indexed: 01/23/2023]
Abstract
In an attempt to identify invariant proteins with vaccine potential against African trypanosomes, we investigated the existence of PFR1 protein in Trypanosoma evansi and compared its B cell epitope with that of PFR2 protein of T. evansi using Western blotting and immuno-precipitation assays. The PFR1 gene of T. evansi was amplified by RT-PCR using primers designed based on the open reading frame of PFR1 gene of Trypanosoma brucei. The cloned PFR1 gene of T.evansi was similar to PFR1 genes of T. brucei and Trypanosoma cruzi. The expressed protein from the PFR1 gene was 68.4% homologous to the PFR2 protein of T. evansi, and showed 99.8%, 87%, 77.9% and 77.5% homologous to the PFR1 protein of T. brucei, T. cruzi, Leishmania mexicana and Leishmania major, respectively. Western blot and immuno-precipitation assays showed that antibodies raised against PFR1 and 2 proteins in BALB/c mice recognized the PFR1 and 2 proteins, respectively, with no cross-reactivity. Immuno-agglutination assay showed trypanolytic properties of the anti-PFR1, anti-PFR2 and anti-native PFR sera. These results suggest that PFR1 and PFR2 proteins are components of native PFR antigen and do not share common B cell epitopes.
Collapse
Affiliation(s)
- M H Abdille
- Parasitology Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing 100193, PR China
| | | | | | | |
Collapse
|
14
|
Rochette A, Raymond F, Ubeda JM, Smith M, Messier N, Boisvert S, Rigault P, Corbeil J, Ouellette M, Papadopoulou B. Genome-wide gene expression profiling analysis of Leishmania major and Leishmania infantum developmental stages reveals substantial differences between the two species. BMC Genomics 2008; 9:255. [PMID: 18510761 PMCID: PMC2453527 DOI: 10.1186/1471-2164-9-255] [Citation(s) in RCA: 116] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2008] [Accepted: 05/29/2008] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Leishmania parasites cause a diverse spectrum of diseases in humans ranging from spontaneously healing skin lesions (e.g., L. major) to life-threatening visceral diseases (e.g., L. infantum). The high conservation in gene content and genome organization between Leishmania major and Leishmania infantum contrasts their distinct pathophysiologies, suggesting that highly regulated hierarchical and temporal changes in gene expression may be involved. RESULTS We used a multispecies DNA oligonucleotide microarray to compare whole-genome expression patterns of promastigote (sandfly vector) and amastigote (mammalian macrophages) developmental stages between L. major and L. infantum. Seven per cent of the total L. infantum genome and 9.3% of the L. major genome were differentially expressed at the RNA level throughout development. The main variations were found in genes involved in metabolism, cellular organization and biogenesis, transport and genes encoding unknown function. Remarkably, this comparative global interspecies analysis demonstrated that only 10-12% of the differentially expressed genes were common to L. major and L. infantum. Differentially expressed genes are randomly distributed across chromosomes further supporting a posttranscriptional control, which is likely to involve a variety of 3'UTR elements. CONCLUSION This study highlighted substantial differences in gene expression patterns between L. major and L. infantum. These important species-specific differences in stage-regulated gene expression may contribute to the disease tropism that distinguishes L. major from L. infantum.
Collapse
Affiliation(s)
- Annie Rochette
- Research Centre in Infectious Diseases, CHUL Research Centre and Department of Medical Biology, Faculty of Medicine, Laval University, Quebec, Canada.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
15
|
Abdille MH, Li SY, Jia Y, Suo X, Mkoji G. Evidence for the existence of paraflagellar rod protein 2 (PFR2) gene in Trypanosoma evansi and its conservation among other kinetoplastid parasites. Exp Parasitol 2007; 118:614-8. [PMID: 18179792 DOI: 10.1016/j.exppara.2007.11.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2007] [Revised: 11/08/2007] [Accepted: 11/12/2007] [Indexed: 11/16/2022]
Abstract
Paraflagellar rod proteins required for cell motility are unique among the kinetoplastids and their heteropolymers provide the building block of the flagellum. We investigated the existence of the paraflagellar rod protein 2 (PFR2) gene in Trypanosoma evansi by reverse transcription-polymerase chain reaction (RT-PCR) using primers designed based on the open reading frame of the PFR2 gene of Trypanosoma brucei. The PFR2 gene was cloned and the PFR2-encoded protein was expressed in bacteria. The expressed His-tag protein was purified using nickel affinity chromatography and confirmed by gel electrophoresis and Western blotting. The nucleotide sequence of the PFR2 gene of T. evansi showed 100% identity with the sequence of the PFR2 gene of T. brucei and 83.4% and 76.6% similarity with that of Trypanosoma cruzi and Leishmania mexicana, respectively. The conserved domain among various PFR2 genes present in kinetoplastids could be used as a target for the development of vaccines against multiple Trypanosoma species.
Collapse
Affiliation(s)
- Md H Abdille
- Parasitology Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing 100094, PR China
| | | | | | | | | |
Collapse
|
16
|
Coordinate regulation of a family of promastigote-enriched mRNAs by the 3'UTR PRE element in Leishmania mexicana. Mol Biochem Parasitol 2007; 157:54-64. [PMID: 18023890 DOI: 10.1016/j.molbiopara.2007.10.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2006] [Revised: 09/11/2007] [Accepted: 10/02/2007] [Indexed: 11/24/2022]
Abstract
Post-transcriptional regulation is a key feature controlling gene expression in the protozoan parasite Leishmania. The nine-nucleotide paraflagellar rod regulatory element (PRE) in the 3'UTR of Leishmania mexicana PFR2 is both necessary and sufficient for the observed 10-fold higher level of PFR2 mRNA in promastigotes compared to amastigotes. It is also found in the 3'UTRs of all known PFR genes. A search of the Leishmania major Friedlin genomic database revealed several genes that share this cis element including a homolog of a heterotrimeric kinesin II subunit, and a gene that shares identity to a homolog of a Plasmodium antigen. In this study, we show that genes that harbor the PRE display promastigote-enriched transcript accumulation ranging from 4- to 15-fold. Northern analysis on episomal block substitution constructs revealed that the regulatory element is necessary for the proper steady-state accumulation of mRNA in L. mexicana paraflagellar rod gene 4 (PFR4). Also we show that the PRE plays a major role in the proper steady-state mRNA accumulation of PFR1, but may not account for the full regulatory mechanism acting on this mRNA. Our evidence suggests that the PRE coordinately regulates the mRNA abundance of not only the PFR family of genes, but also in a larger group of genes that have unrelated functions. Although the PRE alone can regulate some mRNAs, it may also act in concert with additional elements to control other RNA transcripts.
Collapse
|
17
|
Leifso K, Cohen-Freue G, Dogra N, Murray A, McMaster WR. Genomic and proteomic expression analysis of Leishmania promastigote and amastigote life stages: The Leishmania genome is constitutively expressed. Mol Biochem Parasitol 2007; 152:35-46. [PMID: 17188763 DOI: 10.1016/j.molbiopara.2006.11.009] [Citation(s) in RCA: 158] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2006] [Revised: 11/10/2006] [Accepted: 11/13/2006] [Indexed: 10/23/2022]
Abstract
Leishmania are protozoan parasites that cause a wide spectrum of clinical diseases in humans and are a major public health risk in several countries. Leishmania life cycle consists of an extracellular flagellated promastigote stage within the midgut of a sandfly vector, and a morphological distinct intracellular amastigote stage within macrophages of a mammalian host. This study reports the use of DNA oligonucleotide genome microarrays representing 8160 genes to analyze the mRNA expression profiles of L. major promastigotes and lesion derived amastigotes. Over 94% of the genes were expressed in both life stages. Advanced statistical analysis identified a surprisingly low degree of differential mRNA expression: 1.4% of the total genes in amastigotes and 1.5% in promastigotes. These microarray results demonstrate that the L. major genome is essentially constitutively expressed in both life stages and suggest that Leishmania is constitutively adapted for survival and replication in either the sandfly vector or macrophage host utilizing an appropriate set of genes for each vastly different environment. Quantitative proteomics, using the isotope coded affinity tag (ICAT) technology and mass spectrometry, was used to identify L. infantum promastigote and axenic amastigote differentially expressed proteins. Of the 91 distinct proteins identified, 8% were differentially expressed in the amastigote stage, 20% were differentially expressed in the promastigote stage, and the remaining 72% were considered constitutively expressed. The differential expression was validated by the identification of previously reported stage specific proteins and identified several amastigote and promastigote novel stage specific proteins.
Collapse
Affiliation(s)
- Kirk Leifso
- Immunity and Infection Research Centre, Vancouver Coastal Health Research Institute, Canada
| | | | | | | | | |
Collapse
|
18
|
McNicoll F, Drummelsmith J, Müller M, Madore E, Boilard N, Ouellette M, Papadopoulou B. A combined proteomic and transcriptomic approach to the study of stage differentiation in Leishmania infantum. Proteomics 2006; 6:3567-81. [PMID: 16705753 DOI: 10.1002/pmic.200500853] [Citation(s) in RCA: 138] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Protozoan parasites of the genus Leishmania are found as promastigotes in the sandfly vector and as amastigotes in mammalian macrophages. Mechanisms controlling stage-regulated gene expression in these organisms are poorly understood. Here, we applied a comprehensive approach consisting of protein prefractionation, global proteomics and targeted DNA microarray analysis to the study of stage differentiation in Leishmania. By excluding some abundant structural proteins and reducing complexity, we detected and identified numerous novel differentially expressed protein isoforms in L. infantum. Using 2-D gels, over 2200 protein isoforms were visualized in each developmental stage. Of these, 6.1% were strongly increased or appeared unique in the promastigote stage, while the relative amounts of 12.4% were increased in amastigotes. Amastigote-specific protein isoform and mRNA expression trends correlated modestly (53%), while no correlation was found for promastigote-specific spots. Even where direction of regulation was similar, fold-changes were more modest at the RNA than protein level. Many proteins were present in multiple spots, suggesting that PTM is extensive in this organism. In several cases, different isoforms appeared to be specific to different life stages. Our results suggest that post-transcriptional controls at translational and post-translational levels could play major roles in differentiation in Leishmania parasites.
Collapse
Affiliation(s)
- François McNicoll
- Infectious Diseases Research Centre, CHUL Research Centre and Division of Microbiology, Faculty of Medicine, Laval University, Quebec, Canada
| | | | | | | | | | | | | |
Collapse
|
19
|
Holzer TR, McMaster WR, Forney JD. Expression profiling by whole-genome interspecies microarray hybridization reveals differential gene expression in procyclic promastigotes, lesion-derived amastigotes, and axenic amastigotes in Leishmania mexicana. Mol Biochem Parasitol 2006; 146:198-218. [PMID: 16430978 DOI: 10.1016/j.molbiopara.2005.12.009] [Citation(s) in RCA: 134] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2005] [Revised: 11/27/2005] [Accepted: 12/16/2005] [Indexed: 11/22/2022]
Abstract
We examined the Leishmania mexicana transcriptome to identify differentially regulated mRNAs using high-density whole-genome oligonucleotide microarrays designed from the genome data of a closely related species, Leishmania major. Statistical analysis on array hybridization data representing 8156 predicted coding regions revealed 288 genes (3.5% of all genes) whose steady-state mRNA levels meet criteria for differential regulation between promastigotes and lesion-derived amastigotes. Interestingly, sample comparison of promastigotes to axenic amastigotes resulted in only 17 genes (0.2%) that meet the same statistical criteria for differential regulation. The reduced number of regulated genes is a consequence of an increase in the magnitude of the transcript levels in cells under axenic conditions. The expression data for a subset of genes was validated by quantitative PCR. Our studies show that interspecies hybridization on microarrays can be used to analyze closely related protozoan parasites, that axenic culture conditions may alter amastigote transcript abundance, and that there is only a relatively modest change in abundance of a few mRNAs between morphologically distinct promastigote and amastigote cultured cells. Leishmania may represent an alternative paradigm for eukaryotic differentiation with minimal contributions from changes in mRNA abundance.
Collapse
Affiliation(s)
- Timothy R Holzer
- Purdue University, Department of Biochemistry, West Lafayette, IN 47907-2063, USA
| | | | | |
Collapse
|
20
|
Adhiambo C, Forney JD, Asai DJ, LeBowitz JH. The two cytoplasmic dynein-2 isoforms in Leishmania mexicana perform separate functions. Mol Biochem Parasitol 2006; 143:216-25. [PMID: 16054709 DOI: 10.1016/j.molbiopara.2005.04.017] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2004] [Revised: 04/07/2005] [Accepted: 04/20/2005] [Indexed: 11/23/2022]
Abstract
Eukaryotic organisms with cilia or flagella typically express two non-axonemal or "cytoplasmic" dyneins, dynein-1 and dynein-2. Interestingly, we find that Leishmania mexicana is unusual and contains two distinct cytoplasmic dynein-2 heavy chain genes (designated LmxDHC2.1 and LmxDHC2.2) along with a single dynein-1 heavy chain (LmxDHC1). Disruption of LmxDHC2.2 resulted in immotile parasites that had a rounded cell body. Although they assume amastigote morphology, immunoblot analysis of these cells demonstrates protein expression consistent with the promastigote stage. Ultrastructural analysis revealed non-emergent flagella that lacked the paraflagellar rod and an axoneme with deficiencies in several components. We confirmed the absence of paraflagellar rod proteins PFR1 and PFR2. These results show that LmxDHC2.2 is required for flagellar assembly and also participates in the maintenance of promastigote cell shape. In contrast to the results with LmxDHC2.2, we were unable to generate homologous disruptions of LmxDHC2.1. This result suggests that, unlike LmxDHC2.2, LmxDHC2.1 is an essential gene in Leishmania. Together, these findings demonstrate that the two dynein-2 heavy chain isoforms in Leishmania perform distinct functions. The observation that the genomes of Leishmania major, Leishmania infantum and Trypanosoma brucei also contain two dynein-2 isoforms suggests that this unusual aspect of cytoplasmic dynein is a conserved feature of the kinetoplastids.
Collapse
Affiliation(s)
- Christine Adhiambo
- Purdue University, Department of Biochemistry, 175 S. University Street, West Lafayette, IN 47907-2063, USA
| | | | | | | |
Collapse
|
21
|
Clark AK, Kovtunovych G, Kandlikar S, Lal S, Stryker GA. Cloning and expression analysis of two novel paraflagellar rod domain genes found in Trypanosoma cruzi. Parasitol Res 2005; 96:312-20. [PMID: 15918067 DOI: 10.1007/s00436-005-1370-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2005] [Accepted: 03/18/2005] [Indexed: 11/29/2022]
Abstract
The eukaryotic flagellum is one of the most complex macromolecular structures found in cells, containing more than 250 proteins. One unique structure in the flagella of trypanomastids is the paraflagellar rod (PFR). The PFR constitutes a lattice of cytoskeletal filaments that lies alongside the axoneme in the flagella. This unique and complex structure is critical for cell motility, though little is known about its molecular assembly or its role in the lifecycle of trypanosomatids. These proteins are of particular importance in Trypanosoma cruzi, as purified or recombinant PFR proteins have been demonstrated to be immunogenic, protecting mice from a lethal challenge with the parasite. We have searched the T. cruzi databases and discovered two novel genes containing PFR domains. Both these genes are transcribed in vivo and are significantly larger than the previously described PFR genes identified in T. cruzi (>2 Kb). Real-time PCR was used to examine the relative expression levels of six PFR genes, including the two we describe here, in all three stages of T. cruzi's lifecycle. Database searches have further provided EST and genomic sequence support for the presence of these genes in two other pathogenic trypanosomatids, Trypanosoma brucei and Leishmania spp. One of these genes, designated PFR5 contains a carboxy terminal SH3 domain not previously seen in PFR family genes. We propose that this proline-binding SH3 domain may play an important role in the assembly of the PFR.
Collapse
Affiliation(s)
- April K Clark
- Department of Biological Sciences, Oakland University, Rochester, MI 48309-4401, USA
| | | | | | | | | |
Collapse
|
22
|
Rochette A, McNicoll F, Girard J, Breton M, Leblanc E, Bergeron MG, Papadopoulou B. Characterization and developmental gene regulation of a large gene family encoding amastin surface proteins in Leishmania spp. Mol Biochem Parasitol 2005; 140:205-20. [PMID: 15760660 DOI: 10.1016/j.molbiopara.2005.01.006] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2004] [Accepted: 01/14/2005] [Indexed: 11/23/2022]
Abstract
The ability of Leishmania amastigotes to survive within the drastic environmental changes encountered in the phagolysosomes of mammalian macrophages is heavily dependent on the developmental regulation of a variety of genes. The identification of genes that are expressed preferentially in the mammalian stage of the parasite should increase our understanding of the molecular mechanisms regulating stage-specific gene expression and of the determinants that control its intracellular survival and contribute to its pathogenesis. We report here detailed sequence characterization and structural organization of the amastin gene family in Leishmania major and Leishmania infantum and the study of their developmental gene regulation throughout the parasite's life cycle. Amastin surface proteins represent the largest developmentally regulated gene family reported so far in Leishmania comprising up to 45 members. All the members of the amastin gene family in both Leishmania and Trypanosoma species share a similar structural organization and contain a highly conserved 11 amino acid extracellular domain, which is unique to amastin proteins. The majority of the amastin gene homologs are specifically expressed in the amastigote stage of the parasite. Three distinct RNA elements were identified in the 3'-untranslated regions (3'UTR) of the amastin transcripts. The majority of these transcripts contain a conserved 450 nt cis-acting 3'UTR element shown previously to regulate stage-specific gene expression at the level of translation, which suggests that several amastin homologs may be regulated by a similar mechanism of translational control inside the macrophage. These findings further highlight the unique features of gene expression control in Leishmania.
Collapse
Affiliation(s)
- Annie Rochette
- Infectious Diseases Research Center, RC-709, CHUL Research Center and Department of Medical Biology, Faculty of Medicine, Laval University, 2705 Laurier Blvd., Ste-Foy (QC), Que., Canada G1V 4G2
| | | | | | | | | | | | | |
Collapse
|
23
|
Saravia NG, Hazbón MH, Osorio Y, Valderrama L, Walker J, Santrich C, Cortázar T, Lebowitz JH, Travi BL. Protective immunogenicity of the paraflagellar rod protein 2 of Leishmania mexicana. Vaccine 2005; 23:984-95. [PMID: 15620471 DOI: 10.1016/j.vaccine.2004.07.044] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2003] [Revised: 07/19/2004] [Accepted: 07/26/2004] [Indexed: 11/26/2022]
Abstract
Paraflagellar rod proteins (PFR) are a potent immunogen against experimental Trypanosoma cruzi infection. PFR are highly conserved among kinetoplastid parasites. We therefore evaluated the immunogenicity of the Leishmania mexicana pfr-2 gene and protein product in the hamster model of American cutaneous leishmaniasis. Immunization with pfr-2 DNA-induced specific antibody, confirming immunogenicity. Subsequent challenge with 10,000 and 500 stationary phase L. mexicana promastigotes respectively, resulted in delayed appearance of lesions, and significant reduction in lesions post infection in male hamsters, yet exacerbated lesions in female hamsters. Immunization with recombinant PFR-2 protein (rPFR-2) prevented lesion development in female hamsters challenged with L. panamensis, but was ineffective against L. mexicana. Nevertheless, prime boost immunization of female hamsters with rPFR and pfr-2 DNA significantly reduced lesion size following challenge with 500 L. mexicana promastigotes, supporting the relevance of PFR-2 as a potential vaccine constituent.
Collapse
Affiliation(s)
- N G Saravia
- Centro Internacional de Entrenamiento e Investigaciones Médicas, Apartado Aéreo 5390, Cali, Colombia.
| | | | | | | | | | | | | | | | | |
Collapse
|
24
|
Abstract
Eukaryotic cilia and flagella are cytoskeletal organelles that are remarkably conserved from protists to mammals. Their basic unit is the axoneme, a well-defined cylindrical structure composed of microtubules and up to 250 associated proteins. These complex organelles are assembled by a dynamic process called intraflagellar transport. Flagella and cilia perform diverse motility and sensitivity functions in many different organisms. Trypanosomes are flagellated protozoa, responsible for various tropical diseases such as sleeping sickness and Chagas disease. In this review, we first describe general knowledge on the flagellum: its occurrence in the living world, its molecular composition, and its mode of assembly, with special emphasis on the exciting developments that followed the discovery of intraflagellar transport. We then present recent progress regarding the characteristics of the trypanosome flagellum, highlighting the original contributions brought by this organism. The most striking phenomenon is the involvement of the flagellum in several aspects of the trypanosome cell cycle, including cell morphogenesis, basal body migration, and cytokinesis.
Collapse
Affiliation(s)
- Linda Kohl
- INSERM U565, CNRS UMR5153, and MNHN USM 0503, Muséum National d'Histoire Naturelle, 75231 Paris, France
| | | |
Collapse
|
25
|
Gadelha C, LeBowitz JH, Manning J, Seebeck T, Gull K. Relationships between the major kinetoplastid paraflagellar rod proteins: a consolidating nomenclature. Mol Biochem Parasitol 2004; 136:113-5. [PMID: 15138073 DOI: 10.1016/j.molbiopara.2004.03.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2004] [Revised: 03/18/2004] [Accepted: 03/18/2004] [Indexed: 11/26/2022]
|
26
|
Mishra KK, Holzer TR, Moore LL, LeBowitz JH. A negative regulatory element controls mRNA abundance of the Leishmania mexicana Paraflagellar rod gene PFR2. EUKARYOTIC CELL 2004; 2:1009-17. [PMID: 14555483 PMCID: PMC219351 DOI: 10.1128/ec.2.5.1009-1017.2003] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The Leishmania mexicana PFR2 locus encodes a component of the paraflagellar rod (PFR), a flagellar structure found only in the insect stage of the life cycle. PFR2 mRNA levels are 10-fold lower in the mammalian stage than in the insect stage. Nuclear run-on experiments indicate that the change in PFR2 mRNA abundance is achieved posttranscriptionally. Deletion and block substitution analysis of the entire 1,400-nucleotide 3' untranslated region (UTR) of PFR2C led to the identification of a regulatory element contained within 10 nucleotides of the 3' UTR, termed the PFR regulatory element (PRE), that is necessary for the 10-fold regulation of PFR2 mRNA levels. Comparison of the half-lives of PFR2 transcripts, identical except for the presence or absence of the PRE, revealed that the PRE acts by destabilizing the PFR2 mRNA in amastigotes. The PRE was inserted into a construct which directs the constitutive expression of a chimeric PFR2 transcript. Insertion of the PRE resulted in regulated expression of this transcript, demonstrating that the regulatory element is sufficient for promastigote-specific expression. Since the PRE is present in the 3' UTR of all L. mexicana PFR genes examined so far, we propose that it serves a means of coordinating expression of PFR genes.
Collapse
Affiliation(s)
- Krishna K Mishra
- Department of Biochemistry, Purdue University, West Lafayette, Indiana 47907-2063, USA
| | | | | | | |
Collapse
|
27
|
Nugent PG, Karsani SA, Wait R, Tempero J, Smith DF. Proteomic analysis of Leishmania mexicana differentiation. Mol Biochem Parasitol 2004; 136:51-62. [PMID: 15138067 DOI: 10.1016/j.molbiopara.2004.02.009] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2003] [Revised: 02/08/2004] [Accepted: 02/11/2004] [Indexed: 11/20/2022]
Abstract
We have resolved the proteome of axenically differentiated Leishmania mexicana parasites by two-dimensional gel electrophoresis (2DE), employing optimised, robust and reproducible procedures, and visualised (by silver staining) approximately 2000 protein species in each of three developmental stages: procyclic promastigotes, metacyclic promastigotes and amastigotes. This analysis has used homogeneous populations of these parasite stages, characterised according to their morphology, protease and nuclease activity profiles and expression of stage-specific antigens. Following comparison of the whole proteome profiles between stages, 47 spots were found to be stage-specific, while a further 100 spots changed in intensity during differentiation. The majority of "unique" spots were expressed during the infective stages of parasite differentiation, metacyclic promastigotes and amastigotes. CapLC-QTOF mass spectrometry has allowed the identification of 47 protein species to date, including a number which are only detected in the amastigote stage. Proteins identified are members of eight functionally related groupings, some of which are implicated in infectivity and host-parasite interactions.
Collapse
Affiliation(s)
- Philip G Nugent
- Wellcome Trust Laboratories for Molecular Parasitology, Department of Biological Sciences, Centre for Molecular Microbiology and Infection, Imperial College London, Exhibition Road, London SW7 2AZ, UK
| | | | | | | | | |
Collapse
|
28
|
Libusová L, Sulimenko T, Sulimenko V, Hozák P, Dráber P. γ-Tubulin in Leishmania: cell cycle-dependent changes in subcellular localization and heterogeneity of its isoforms. Exp Cell Res 2004; 295:375-86. [PMID: 15093737 DOI: 10.1016/j.yexcr.2004.01.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2003] [Revised: 12/15/2003] [Indexed: 12/01/2022]
Abstract
A panel of six anti-peptide antibodies recognizing epitopes in different regions of the gamma-tubulin molecule was used for the characterization and localization of gamma-tubulin during cell cycle in Leishmania promastigotes. Immunofluorescence microscopy revealed the presence of gamma-tubulin in the basal bodies, posterior pole of the cell, and in the flagellum. Furthermore, the antibodies showed punctuate staining in the subpellicular microtubule. This complex localization pattern was observed in both interphase and dividing cells, where staining of posterior poles and the subpellicular corset was more prominent. In posterior poles, gamma-tubulin co-distributed with the 210-kDa microtubule-interacting protein and the 57-kDa protein immunodetected with anti-vimentin antibody. Immunogold electron microscopy on thin sections of isolated flagella showed that gamma-tubulin was associated with the paraflagellar rod (PFR) that runs adjacent to the axonemal microtubules. Under different extraction conditions, gamma-tubulin in Leishmania was found only in insoluble cytoskeletal fractions, in contrast to tubulin dimers that were both in soluble and cytoskeletal pool. Two-dimensional electrophoresis revealed multiple charge variants of gamma-tubulin. Posttranslational modifications of Leishmania gamma-tubulin might therefore have an important role in the regulation of microtubule nucleation and interaction with other proteins. The complex pattern of gamma-tubulin localization and its properties indicate that gamma-tubulin in Leishmania might have other function(s) besides microtubule nucleation.
Collapse
Affiliation(s)
- Lenka Libusová
- Department of Biology of the Cytoskeleton, Institute of Molecular Genetics, Czech Academy of Sciences, CZ-14220 Prague, Czech Republic
| | | | | | | | | |
Collapse
|
29
|
Burchmore RJS, Rodriguez-Contreras D, McBride K, Merkel P, Barrett MP, Modi G, Sacks D, Landfear SM. Genetic characterization of glucose transporter function in Leishmania mexicana. Proc Natl Acad Sci U S A 2003; 100:3901-6. [PMID: 12651954 PMCID: PMC153020 DOI: 10.1073/pnas.0630165100] [Citation(s) in RCA: 109] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Both insect and mammalian life cycle stages of Leishmania mexicana take up glucose and express all three isoforms encoded by the LmGT glucose transporter gene family. To evaluate glucose transporter function in intact parasites, a null mutant line has been created by targeted disruption of the LmGT locus that encompasses the LmGT1, LmGT2, and LmGT3 genes. This deltalmgt null mutant exhibited no detectable glucose transport activity. The growth rate of the deltalmgt knockout in the promastigote stage was reduced to a rate comparable with that of WT cells grown in the absence of glucose. deltalmgt cells also exhibited dramatically reduced infectivity to macrophages, demonstrating that expression of LmGT isoforms is essential for viability of amastigotes. Furthermore, WT L. mexicana were not able to grow as axenic culture form amastigotes if glucose was withdrawn from the medium, implying that glucose is an essential nutrient in this life cycle stage. Expression of either LmGT2 or LmGT3, but not of LmGT1, in deltalmgt null mutants significantly restored growth as promastigotes, but only LmGT3 expression substantially rescued amastigote growth in macrophages. Subcellular localization of the three isoforms was investigated in deltalmgt cells expressing individual LmGT isoforms. Using anti-LmGT antiserum and GFP-tagged LmGT fusion proteins, LmGT2 and LmGT3 were localized to the cell body, whereas LmGT1 was localized specifically to the flagellum. These results establish that each glucose transporter isoform has distinct biological functions in the parasite.
Collapse
Affiliation(s)
- Richard J S Burchmore
- Institute of Biomedical and Life Sciences, Division of Infection and Immunity, Joseph Black Building, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | | | | | | | | | | | | | | |
Collapse
|
30
|
Bastin P, Pullen TJ, Moreira-Leite FF, Gull K. Inside and outside of the trypanosome flagellum:a multifunctional organelle. Microbes Infect 2000; 2:1865-74. [PMID: 11165931 DOI: 10.1016/s1286-4579(00)01344-7] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Amongst the earliest eukaryotes, trypanosomes have developed conventional organelles but sometimes with extreme features rarely seen in other organisms. This is the case of the flagellum, containing conventional and unique structures whose role in infectivity is still enigmatic.
Collapse
Affiliation(s)
- P Bastin
- Department of Biochemistry, School of Biological Sciences, University of Manchester, 2.205 Stopford Building, Oxford Road, M13 9PT, Manchester, UK.
| | | | | | | |
Collapse
|
31
|
Wu Y, El Fakhry Y, Sereno D, Tamar S, Papadopoulou B. A new developmentally regulated gene family in Leishmania amastigotes encoding a homolog of amastin surface proteins. Mol Biochem Parasitol 2000; 110:345-57. [PMID: 11071288 DOI: 10.1016/s0166-6851(00)00290-5] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The ability of Leishmania to survive within the phagolysosomes of mammalian macrophages is heavily dependent on the developmental regulation of a number of genes. Characterization of genes preferentially expressed during the parasite's intracellular growth would help to elucidate the mechanisms controlling stage-specific gene regulation and the intracellular life of the parasite in general. Using a genomic approach based on the differential hybridization screening of high-density filters, we have identified a new developmentally regulated gene in Leishmania, which is part of a multigene family and encodes a highly hydrophobic protein that shares homology with the Trypanosoma cruzi amastin proteins. The fusion of the Leishmania amastin gene homolog with the green fluorescent protein and analysis by confocal microscopy suggested a surface localization for this protein. The amastin gene homolog is expressed predominantly in the amastigote form of several Leishmania species and is strictly regulated by acidic pH at the post-transcriptional level. Its developmental expression involves sequences within the 3'-untranslated region.
Collapse
Affiliation(s)
- Y Wu
- Centre de Recherche en Infectiologie du Centre de Recherche du CHUL et Département de Biologie Médicale, University Laval, Québec, Canada
| | | | | | | | | |
Collapse
|
32
|
Bastin P, MacRae TH, Francis SB, Matthews KR, Gull K. Flagellar morphogenesis: protein targeting and assembly in the paraflagellar rod of trypanosomes. Mol Cell Biol 1999; 19:8191-200. [PMID: 10567544 PMCID: PMC84903 DOI: 10.1128/mcb.19.12.8191] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/1999] [Accepted: 09/13/1999] [Indexed: 11/20/2022] Open
Abstract
The paraflagellar rod (PFR) of the African trypanosome Trypanosoma brucei represents an excellent model to study flagellum assembly. The PFR is an intraflagellar structure present alongside the axoneme and is composed of two major proteins, PFRA and PFRC. By inducible expression of a functional epitope-tagged PFRA protein, we have been able to monitor PFR assembly in vivo. As T. brucei cells progress through their cell cycle, they possess both an old and a new flagellum. The induction of expression of tagged PFRA in trypanosomes growing a new flagellum provided an excellent marker of newly synthesized subunits. This procedure showed two different sites of addition: a major, polar site at the distal tip of the flagellum and a minor, nonpolar site along the length of the partially assembled PFR. Moreover, we have observed turnover of epitope-tagged PFRA in old flagella that takes place throughout the length of the PFR structure. Expression of truncated PFRA mutant proteins identified a sequence necessary for flagellum localization by import or binding. This sequence was not sufficient to confer full flagellum localization to a green fluorescent protein reporter. A second sequence, necessary for the addition of PFRA protein to the distal tip, was also identified. In the absence of this sequence, the mutant PFRA proteins were localized both in the cytosol and in the flagellum where they could still be added along the length of the PFR. This seven-amino-acid sequence is conserved in all PFRA and PFRC proteins and shows homology to a sequence in the flagellar dynein heavy chain of Chlamydomonas reinhardtii.
Collapse
Affiliation(s)
- P Bastin
- School of Biological Sciences, University of Manchester, Manchester M13 9PT, United Kingdom.
| | | | | | | | | |
Collapse
|
33
|
Abstract
Species of the trypanosomatid parasite genera Trypanosoma and Leishmania exhibit a particular range of cell shapes that are defined by their internal cytoskeletons. The cytoskeleton is characterized by a subpellicular corset of microtubules that are cross-linked to each other and to the plasma membrane. Trypanosomatid cells possess an extremely precise organization of microtubules and filaments, with some of their organelles, such as the mitochondria, kinetoplasts, basal bodies, and flagella, present as single copies in each cell. The duplication of these structures and changes in their position during life cycle differentiations provide markers and insight into events involved in determining cell form and division. We have a rapidly increasing catalog of these structures, their molecular cytology, and their ontogeny. The current sophistication of available molecular genetic techniques for use in these organisms has allowed a new functional analysis of the cytoskeleton, including functions that are intrinsic to the proliferation and pathogenicity of these parasites.
Collapse
Affiliation(s)
- K Gull
- School of Biological Sciences, University of Manchester, United Kingdom.
| |
Collapse
|
34
|
Bastin P, Pullen TJ, Sherwin T, Gull K. Protein transport and flagellum assembly dynamics revealed by analysis of the paralysed trypanosome mutant snl-1. J Cell Sci 1999; 112 ( Pt 21):3769-77. [PMID: 10523512 DOI: 10.1242/jcs.112.21.3769] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The paraflagellar rod (PFR) of Trypanosoma brucei is a large, complex, intraflagellar structure that represents an excellent system in which to study flagellum assembly. Molecular ablation of one of its major constituents, the PFRA protein, in the snl-1 mutant causes considerable alteration of the PFR structure, leading to cell paralysis. Mutant trypanosomes sedimented to the bottom of the flask rather than staying in suspension but divided at a rate close to that of wild-type cells. This phenotype was complemented by transformation of snl-1 with a plasmid overexpressing an epitope-tagged copy of the PFRA gene. In the snl-1 mutant, other PFR proteins such as the second major constituent, PFRC, accumulated at the distal tip of the growing flagellum, forming a large dilation or ‘blob’. This was not assembled as filaments and was removed by detergent-extraction. Axonemal growth and structure was unmodified in the snl-1 mutant and the blob was present only at the tip of the new flagellum. Strikingly, the blob of unassembled material was shifted towards the base of the flagellum after cell division and was not detectable when the daughter cell started to produce a new flagellum in the next cell cycle. The dynamics of blob formation and regression are likely indicators of anterograde and retrograde transport systems operating in the flagellum. In this respect, the accumulation of unassembled PFR precursors in the flagellum shows interesting similarities with axonemal mutants in other systems, illustrating transport of components of a flagellar structure during both flagellum assembly and maintenance. Observation of PFR components indicate that these are likely to be regulated and modulated throughout the cell cycle.
Collapse
Affiliation(s)
- P Bastin
- School of Biological Sciences, University of Manchester, Oxford Road, Manchester M13 9PT, UK.
| | | | | | | |
Collapse
|
35
|
Moreira-Leite FF, de Souza W, da Cunha-e-Silva NL. Purification of the paraflagellar rod of the trypanosomatid Herpetomonas megaseliae and identification of some of its minor components. Mol Biochem Parasitol 1999; 104:131-40. [PMID: 10589987 DOI: 10.1016/s0166-6851(99)00143-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
The paraflagellar rod (PFR) is a component of the flagellar cytoskeleton of trypanosomatid protozoa, representing a filamentous structure that runs alongside the common 9 + 2 microtubular axoneme. The high degree of ultrastructural complexity and organization of the PFR suggests that it might be formed by numerous biochemical components. However, biochemical analysis of the PFR has revealed, to date, a modest degree of complexity in what concerns both major and minor PFR proteins. In this paper the preparation of purified PFR fractions by a combination of conventional cell-fractionation procedures, non-ionic detergent treatment and limited proteolysis is described. Comparative SDS-PAGE analysis of the different purification steps indicates that the purified PFR fractions possess high amounts of the well-known major PFR proteins (77 and 83 kDa). Also, bands of 147, 139, 129 and 122 kDa are clearly enriched in such fractions and may correspond to minor PFR components. A slight enrichment in a specific fraction of a doublet of bands of 181/188 kDa suggest the participation of these proteins in the composition of the bridges between the PFR and the axoneme.
Collapse
Affiliation(s)
- F F Moreira-Leite
- Instituto de Biofisica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, RJ, Brazil
| | | | | |
Collapse
|
36
|
Abstract
Researchers who study human pathogens are often interested in unique and essential aspects of the biology of the pathogen. Recent progress has been made in understanding such a target in kinetoplastid parasites. The paraflagellar rod is a unique cytoskeletal structure that plays a key role in the life-cycle of these fascinating organisms. This review discusses the protein components and structure of the paraflagellar rod and its function in cell motility.
Collapse
Affiliation(s)
- J A Maga
- Dept of Biochemistry, Purdue University, West Lafayette, IN 47907, USA
| | | |
Collapse
|
37
|
Maga JA, Sherwin T, Francis S, Gull K, LeBowitz JH. Genetic dissection of the Leishmania paraflagellar rod, a unique flagellar cytoskeleton structure. J Cell Sci 1999; 112 ( Pt 16):2753-63. [PMID: 10413682 DOI: 10.1242/jcs.112.16.2753] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The paraflagellar rod (PFR) is a unique network of cytoskeletal filaments that lies alongside the axoneme in the flagella of most trypanosomatids. While little is known about how two major Leishmania mexicana PFR protein components, PFR1 and PFR2, assemble into this complex structure, previous analysis of PFR2 null mutants demonstrated that the PFR is essential for proper cell motility. The structural roles of PFR1 and PFR2 are now examined through comparison of PFR2 null mutants with new PFR1 null mutant and PFR1/PFR2 double null mutant parasites. Both PFR1 and PFR2 were essential for PFR formation and cell motility. When elimination of one PFR gene prevented assembly of a native PFR structure, the other PFR protein accumulated at the distal flagellar tip. Comparison of PFR substructures remaining in each mutant revealed that: (1) fibers that attach the PFR to the axoneme did not contain PFR1 or PFR2, and assemble in the absence of a PFR. (2) PFR1 was synthesized and transported to the flagella in the absence of PFR2, where it formed a stable association with the axoneme attachment fibers. (3) PFR2 was synthesized and transported to the flagella in the absence of PFR1, though it was not found associated with the axoneme attachment fibers. (4) PFR1 and PFR2 were located throughout the subdomains of the PFR. These data suggest that while PFR filaments contain both PFR1 and PFR2, the PFR is attached to the axoneme by interaction of PFR1 with the axoneme attachment fibers.
Collapse
Affiliation(s)
- J A Maga
- Department of Biochemistry, Purdue University, West Lafayette, IN 47907, USA
| | | | | | | | | |
Collapse
|
38
|
Bastin P, Gull K. Assembly and function of complex flagellar structures illustrated by the paraflagellar rod of trypanosomes. Protist 1999; 150:113-23. [PMID: 10505412 DOI: 10.1016/s1434-4610(99)70015-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
39
|
Burchmore RJ, Landfear SM. Differential regulation of multiple glucose transporter genes in Leishmania mexicana. J Biol Chem 1998; 273:29118-26. [PMID: 9786920 DOI: 10.1074/jbc.273.44.29118] [Citation(s) in RCA: 73] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We have studied the structure and expression of glucose transporter genes in the parasitic protozoan Leishmania mexicana. Three distinct glucose transporter isoforms, LmGT1, LmGT2, and LmGT3, are encoded by single copy genes that are clustered together at a single locus. Quantitation of Northern blots reveals that LmGT2 mRNA is present at approximately 15-fold higher level in promastigotes, the insect stage of the parasite life cycle, compared with amastigotes, the intracellular stage of the life cycle that lives within the mammalian host. In contrast, LmGT1 and LmGT3 mRNAs are expressed at similar levels in both life cycle stages. Transcription of the LmGT genes in promastigotes and axenically cultured amastigotes occurs at similar levels, as measured by nuclear run-on transcription. Consequently, the approximately 15-fold up-regulation of LmGT2 mRNA levels in promastigotes compared with amastigotes must be controlled at the post-transcriptional level. Measurement of LmGT2 RNA decay in promastigotes and axenic amastigotes treated with actinomycin D suggests that differential mRNA stability may play a role in regulating glucose transporter mRNA levels in the two life cycle stages.
Collapse
Affiliation(s)
- R J Burchmore
- Department of Molecular Microbiology and Immunology, Oregon Health Sciences University, Portland, Oregon 97201, USA
| | | |
Collapse
|
40
|
Fouts DL, Stryker GA, Gorski KS, Miller MJ, Nguyen TV, Wrightsman RA, Manning JE. Evidence for four distinct major protein components in the paraflagellar rod of Trypanosoma cruzi. J Biol Chem 1998; 273:21846-55. [PMID: 9705323 DOI: 10.1074/jbc.273.34.21846] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The major structural proteins present in the paraflagellar rod of Trypanosoma cruzi migrate on SDS-polyacrylamide gels as two distinct electrophoretic bands. The gene encoding a protein present in the faster migrating band, designated PAR 2, has been identified previously. Here we report the isolation and partial characterization of three genes, designated par 1, par 3, and par 4, that encode proteins present in the two paraflagellar rod protein bands. Peptide-specific polyclonal antibodies and monoclonal antibodies against the four proteins encoded by these genes shows that PAR 1 and PAR 3 are present only in the slower migrating paraflagellar rod band, and that PAR 2 and PAR 4 are present only in the faster migrating band. Analysis of the nucleotide sequence of these genes and the amino acid sequence of the conceptual proteins encoded by them indicates that par 2 shares high sequence similarity with par 3 and both are members of a common gene family, of which par 1 may be a distant member. Analysis of gene copy number and steady-state RNA levels suggest that the close stoichiometric ratio of the four PAR proteins is likely maintained by homeostatic regulation of RNA levels rather than gene dosage.
Collapse
Affiliation(s)
- D L Fouts
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California 92697-3900, USA
| | | | | | | | | | | | | |
Collapse
|
41
|
Ngô HM, Bouck GB. Heterogeneity and a coiled coil prediction of trypanosomatid-like flagellar rod proteins in Euglena. J Eukaryot Microbiol 1998; 45:323-33. [PMID: 9627992 DOI: 10.1111/j.1550-7408.1998.tb04543.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The emergent flagellum of euglenoids and trypanosomatids contained in addition to microtubules a prominent filamentous structure--the flagellar rod (paraflagellar/paraxonemal rod). Immunoblots and immunofluorescence localization using three antibodies generated against gel-isolated proteins confirmed previous studies that the Euglena flagellar rod consisted of polypeptides migrating at 66-, 69-, and 75-kD. Immunoblotting after two dimensional gel electrophoresis identified ten or more isoforms of these polypeptides. Differences in migration in acrylamide gels under nonreducing and reducing conditions suggested that the rod proteins contain intramolecular disulfide linkages. Comparative peptide mapping showed that the 66-, 69-, and 75-kD polypeptides were distinct, but related proteins, and also identified a fourth related protein migrating at 64-kD. Using antibodies against rod proteins, two overlapping cDNAs were isolated and from their sequences the cDNAs were predicted to encode 334 amino acids of the 66-kD protein; the amino acid sequence had > 65% identity to the carboxyl-terminus of the trypanosomatid flagellar rod proteins. Secondary structural prediction suggested that flagellar rod proteins contain an extended segmented coiled coil stalk and two nonhelical heads. Coiled coil appeared to be an important structural motif in the construction of flagellar rod filaments.
Collapse
Affiliation(s)
- H M Ngô
- Department of Biological Sciences (m/c 066), University of Illinois at Chicago 60607-7080, USA.
| | | |
Collapse
|
42
|
Hunger-Glaser I, Seebeck T. Deletion of the genes for the paraflagellar rod protein PFR-A in Trypanosoma brucei is probably lethal. Mol Biochem Parasitol 1997; 90:347-51. [PMID: 9497059 DOI: 10.1016/s0166-6851(97)00139-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- I Hunger-Glaser
- Institut für Allgemeine Mikrobiologie, Universität Bern, Switzerland
| | | |
Collapse
|
43
|
Santrich C, Moore L, Sherwin T, Bastin P, Brokaw C, Gull K, LeBowitz JH. A motility function for the paraflagellar rod of Leishmania parasites revealed by PFR-2 gene knockouts. Mol Biochem Parasitol 1997; 90:95-109. [PMID: 9497035 DOI: 10.1016/s0166-6851(97)00149-7] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
We demonstrate a functional role for the paraflagellar rod (PFR) in motility of Leishmania mexicana. The PFR is a complex cytoskeletal structure running parallel to the axoneme in the flagella of kinetoplastid protozoa. The PFR is composed of a latticework of protein filaments whose major constituents are two related proteins (PFR-1 and PFR-2 in Leishmania). The molecular details of their assembly into PFR filaments are unknown as is the biological function of the PFR. As an approach to understanding the structure and function of the PFR in Leishmania, we made L. mexicana null mutants of PFR-2. PFR-2 minus parasites grow and divide normally in culture and still express the PFR-1 protein. They lack most of the PFR structure demonstrating that the PFR-2 protein is an essential constituent of the PFR. Detailed ultrastructural analysis of the PFR-2 null mutant reveals the presence of a residual inner substructure of the PFR which contains PFR-1 protein, indicating that PFR-1 can polymerize in the absence of PFR-2. The PFR-2 null mutant displays pronounced changes in flagellar beat waveform and forward swimming velocity, compared to wild type parasites consistent with decreased internal elastic bending resistance in PFR-lacking flagella, and indicating a functional role for the PFR in the motility of Leishmania.
Collapse
Affiliation(s)
- C Santrich
- Department of Biochemistry, Purdue University, West Lafayette, IN 47907, USA
| | | | | | | | | | | | | |
Collapse
|