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Borges FS, Quilles JC, Lorenzon LB, Espada CR, Freitas-Castro F, Defina TPA, Holetz FB, Cruz AK. Leishmania Ribosomal Protein (RP) paralogous genes compensate each other's expression maintaining protein native levels. PLoS One 2024; 19:e0292152. [PMID: 38753846 PMCID: PMC11098316 DOI: 10.1371/journal.pone.0292152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Accepted: 04/22/2024] [Indexed: 05/18/2024] Open
Abstract
In the protozoan parasite Leishmania, most genes encoding for ribosomal proteins (RPs) are present as two or more copies in the genome. However, their untranslated regions (UTRs) are predominantly divergent and might be associated with a distinct regulation of the expression of paralogous genes. Herein, we investigated the expression profiles of two RPs (S16 and L13a) encoded by duplicated genes in Leishmania major. The genes encoding for the S16 protein possess identical coding sequences (CDSs) and divergent UTRs, whereas the CDSs of L13a diverge by two amino acids and by their UTRs. Using CRISPR/Cas9 genome editing, we generated knockout (Δ) and endogenously tagged transfectants for each paralog of L13a and S16 genes. Combining tagged and Δ cell lines we found evidence of differential expression of both RPS16 and RPL13a isoforms throughout parasite development, with one isoform consistently more abundant than its respective copy. In addition, compensatory expression was observed for each paralog upon deletion of the corresponding isoform, suggesting functional conservation between these proteins. This differential expression pattern relates to post-translational processes, given compensation occurs at the level of the protein, with no alterations detected at transcript level. Ribosomal profiles for RPL13a indicate a standard behavior for these paralogues suggestive of interaction with heavy RNA-protein complexes, as already reported for other RPs in trypanosomatids. We identified paralog-specific bound to their 3'UTRs which may be influential in regulating paralog expression. In support, we identified conserved cis-elements within the 3'UTRs of RPS16 and RPL13a; cis-elements exclusive to the UTR of the more abundant paralog or to the less abundant ones were identified.
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Affiliation(s)
- Francisca S. Borges
- Department of Cell and Molecular Biology, Ribeirão Preto Medical School, FMRP/USP–University of São Paulo, São Paulo, Brazil
| | - José C. Quilles
- Department of Cell and Molecular Biology, Ribeirão Preto Medical School, FMRP/USP–University of São Paulo, São Paulo, Brazil
| | - Lucas B. Lorenzon
- Department of Cell and Molecular Biology, Ribeirão Preto Medical School, FMRP/USP–University of São Paulo, São Paulo, Brazil
| | - Caroline R. Espada
- Department of Cell and Molecular Biology, Ribeirão Preto Medical School, FMRP/USP–University of São Paulo, São Paulo, Brazil
| | - Felipe Freitas-Castro
- Department of Cell and Molecular Biology, Ribeirão Preto Medical School, FMRP/USP–University of São Paulo, São Paulo, Brazil
| | - Tânia P. A. Defina
- Department of Cell and Molecular Biology, Ribeirão Preto Medical School, FMRP/USP–University of São Paulo, São Paulo, Brazil
| | - Fabíola B. Holetz
- Laboratory of Gene Expression Regulation, Carlos Chagas Institute, Oswaldo Cruz Foundation, Curitiba, Paraná, Brazil
| | - Angela K. Cruz
- Department of Cell and Molecular Biology, Ribeirão Preto Medical School, FMRP/USP–University of São Paulo, São Paulo, Brazil
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2
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Myburgh E, Geoghegan V, Alves-Ferreira EV, Nievas YR, Grewal JS, Brown E, McLuskey K, Mottram JC. TORC1 is an essential regulator of nutrient-controlled proliferation and differentiation in Leishmania. EMBO Rep 2024; 25:1075-1105. [PMID: 38396206 PMCID: PMC10933368 DOI: 10.1038/s44319-024-00084-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 01/19/2024] [Accepted: 01/25/2024] [Indexed: 02/25/2024] Open
Abstract
Leishmania parasites undergo differentiation between various proliferating and non-dividing forms to adapt to changing host environments. The mechanisms that link environmental cues with the parasite's developmental changes remain elusive. Here, we report that Leishmania TORC1 is a key environmental sensor for parasite proliferation and differentiation in the sand fly-stage promastigotes and for replication of mammalian-stage amastigotes. We show that Leishmania RPTOR1, interacts with TOR1 and LST8, and identify new parasite-specific proteins that interact in this complex. We investigate TORC1 function by conditional deletion of RPTOR1, where under nutrient-rich conditions RPTOR1 depletion results in decreased protein synthesis and growth, G1 cell cycle arrest and premature differentiation from proliferative promastigotes to non-dividing mammalian-infective metacyclic forms. These parasites are unable to respond to nutrients to differentiate into proliferative retroleptomonads, which are required for their blood-meal induced amplification in sand flies and enhanced mammalian infectivity. We additionally show that RPTOR1-/- metacyclic promastigotes develop into amastigotes but do not proliferate in the mammalian host to cause pathology. RPTOR1-dependent TORC1 functionality represents a critical mechanism for driving parasite growth and proliferation.
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Affiliation(s)
- Elmarie Myburgh
- York Biomedical Research Institute, Hull York Medical School, University of York, York, YO10 5DD, UK.
| | - Vincent Geoghegan
- York Biomedical Research Institute, Department of Biology, University of York, York, YO10 5DD, UK
| | - Eliza Vc Alves-Ferreira
- York Biomedical Research Institute, Department of Biology, University of York, York, YO10 5DD, UK
| | - Y Romina Nievas
- York Biomedical Research Institute, Department of Biology, University of York, York, YO10 5DD, UK
| | - Jaspreet S Grewal
- York Biomedical Research Institute, Department of Biology, University of York, York, YO10 5DD, UK
| | - Elaine Brown
- York Biomedical Research Institute, Department of Biology, University of York, York, YO10 5DD, UK
| | - Karen McLuskey
- Wellcome Centre for Integrative Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical Veterinary and Life Sciences, University of Glasgow, Glasgow, G12 8TA, UK
| | - Jeremy C Mottram
- York Biomedical Research Institute, Department of Biology, University of York, York, YO10 5DD, UK
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3
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Nation CS, Stephany-Brassesco I, Kelly BL, Pizarro JC. Transgenic overexpression of heat shock protein (HSP83) enhances protein kinase A activity, disrupts GP63 surface protease expression and alters promastigote morphology in Leishmania amazonensis. Mol Biochem Parasitol 2023; 255:111574. [PMID: 37150327 DOI: 10.1016/j.molbiopara.2023.111574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 04/18/2023] [Accepted: 05/02/2023] [Indexed: 05/09/2023]
Abstract
Leishmania parasites undergo morphological changes during their infectious life cycle, including developmental transitions within the sandfly vector, culminating in metacyclic stages that are pre-adapted for infection. Upon entering vertebrate host phagocytes, Leishmania differentiate into intracellular amastigotes, the form that is ultimately transmitted back to the vector to complete the life cycle. Although environmental conditions that induce these cellular transitions are well-established, molecular mechanisms governing Leishmania morphologic differentiation in response to these cues remain largely uncharacterized. Previous studies indicate a key role for HSP83 in both promastigote metacyclogenesis and amastigote differentiation. To further elucidate HSP83 functions in the Leishmania lifecycle, we examined the biological impact of experimentally elevating HSP83 gene expression in Leishmania. Significantly, HSP83 overexpression was associated with altered metacyclic morphology, increased protein kinase A (PKA) activity and decreased expression of the Leishmania major surface protease, GP63. Corroborating these findings, overexpression of the L. amazonensis PKA catalytic subunit resulted in a largely similar phenotype. Our findings demonstrate for the first time in Leishmania, a functional link between HSP83 and PKA in the control of Leishmania gene expression, replication and morphogenesis.
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Affiliation(s)
- Catherine S Nation
- Department of Tropical Medicine, Tulane University,1440 Canal St., Suite 2301, New Orleans, LA 70112, USA
| | - Isabel Stephany-Brassesco
- Department of Microbiology, Immunology and Parasitology, Louisiana State University Health Sciences Center, 1901 Perdido St., New Orleans, LA 70112, USA
| | - Ben L Kelly
- Department of Microbiology, Immunology and Parasitology, Louisiana State University Health Sciences Center, 1901 Perdido St., New Orleans, LA 70112, USA.
| | - Juan C Pizarro
- Department of Tropical Medicine, Tulane University,1440 Canal St., Suite 2301, New Orleans, LA 70112, USA.
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4
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Henriquez-Figuereo A, Moreno E, Sanmartin C, Plano D. Exploring Novel Drug Combinations: The Therapeutic Potential of Selanyl Derivatives for Leishmania Treatment. Molecules 2023; 28:5845. [PMID: 37570815 PMCID: PMC10420963 DOI: 10.3390/molecules28155845] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 07/31/2023] [Accepted: 08/01/2023] [Indexed: 08/13/2023] Open
Abstract
This work describes the design, synthesis, and biological activities of new selenoester derivatives and its homologs thioesters. Thirty-two compounds were developed following an economical synthetic route, achieving small molecules, with structural characteristics similar to those present in antileishmanial drugs such as miltefosine (MIL) and paromomycin (PMN). These compounds were tested in vitro against strains of Leishmania major (L. major) and Leishmania infantum (L. infantum). The L. infantum strain (causative agent of visceral leishmaniasis) exhibited the highest sensitivity. Thus, four selanylacetic acid derivatives (A4, A5, A6 and A8) presented IC50 values below 40 µM in this strain. These derivatives also demonstrated low toxicity and high selectivity in PMA-differentiated THP-1 macrophages. The A4-A6 and A8 derivatives were evaluated in order to determine their pharmacological behavior, using drug combination studies with the reference drugs amphotericin B (AMB), MIL and PMN. Compounds A6 and A8 presented a potent synergistic interaction with MIL, which is the only oral drug available for the treatment of visceral leishmaniasis. Therefore, compounds A6 and A8 present significant potential as therapeutic candidates for the treatment of leishmaniasis based on their remarkable leishmanicidal characteristics and pharmacological synergism.
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Affiliation(s)
- Andreina Henriquez-Figuereo
- Department of Pharmaceutical Technology and Chemistry, Faculty of Pharmacy and Nutrition, University of Navarra, 31008 Pamplona, Spain; (A.H.-F.); (E.M.)
- Institute of Tropical Health (ISTUN), University of Navarra, 31008 Pamplona, Spain
| | - Esther Moreno
- Department of Pharmaceutical Technology and Chemistry, Faculty of Pharmacy and Nutrition, University of Navarra, 31008 Pamplona, Spain; (A.H.-F.); (E.M.)
- Institute of Tropical Health (ISTUN), University of Navarra, 31008 Pamplona, Spain
- Navarra Institute for Health Research (IdisNA), 31008 Pamplona, Spain
| | - Carmen Sanmartin
- Department of Pharmaceutical Technology and Chemistry, Faculty of Pharmacy and Nutrition, University of Navarra, 31008 Pamplona, Spain; (A.H.-F.); (E.M.)
- Institute of Tropical Health (ISTUN), University of Navarra, 31008 Pamplona, Spain
- Navarra Institute for Health Research (IdisNA), 31008 Pamplona, Spain
| | - Daniel Plano
- Department of Pharmaceutical Technology and Chemistry, Faculty of Pharmacy and Nutrition, University of Navarra, 31008 Pamplona, Spain; (A.H.-F.); (E.M.)
- Institute of Tropical Health (ISTUN), University of Navarra, 31008 Pamplona, Spain
- Navarra Institute for Health Research (IdisNA), 31008 Pamplona, Spain
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5
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Chanmol W, Jariyapan N, Preativatanyou K, Mano C, Tippawangkosol P, Somboon P, Bates PA. Stimulation of metacyclogenesis in Leishmania (Mundinia) orientalis for mass production of metacyclic promastigotes. Front Cell Infect Microbiol 2022; 12:992741. [PMID: 36132986 PMCID: PMC9483143 DOI: 10.3389/fcimb.2022.992741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 08/17/2022] [Indexed: 11/24/2022] Open
Abstract
Leishmania (Mundinia) orientalis is a human pathogen causing leishmaniasis and studies on the properties of metacyclic promastigotes, the parasite’s infective stage, are required for a better understanding of its transmission and infection. However, information on cultivation for mass production of L. orientalis metacyclic promastigotes and factors that stimulate their metacyclogenesis is limited. Therefore, the objective of this study was to develop a suitable methodology for generating promastigote cultures containing a high proportion and number of L. orientalis metacyclic promastigotes. Various media, i.e., Schneider’s insect medium, Medium 199 and Grace’s insect medium, supplemented with various quantities of dithiothreitol, Basal Medium Eagle vitamins, pooled human urine, and fetal bovine serum, were optimized for metacyclogenesis. The results revealed that the optimum culture medium and conditions of those tested were Schneider’s insect medium supplemented with 100 μM dithiothreitol, 1% (v/v) Basal Medium Eagle vitamins, 2% (v/v) pooled human urine, and 10% (v/v) fetal bovine serum, pH 5.0 at 26°C. We also demonstrated that L. orientalis metacyclic promastigotes could be purified and enriched by negative selection using peanut lectin. Under these culture conditions, the highest yield of metacyclic promastigotes was obtained with a significantly higher percentage of parasite survival, resistance to complement-mediated lysis, and infection index in THP-1 macrophage cells compared to parasites cultured without media supplements at neutral pH. This is the first report providing a reliable method for mass production of L. orientalis metacyclic promastigotes for in vivo infections and other experimental studies of this emerging parasite in the future.
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Affiliation(s)
- Wetpisit Chanmol
- School of Allied Health Sciences, Walailak University, Nakhonsithammarat, Thailand
| | - Narissara Jariyapan
- Center of Excellence in Vector Biology and Vector-Borne Disease, Department of Parasitology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
- *Correspondence: Narissara Jariyapan, ; Pradya Somboon,
| | - Kanok Preativatanyou
- Center of Excellence in Vector Biology and Vector-Borne Disease, Department of Parasitology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Chonlada Mano
- Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Pongsri Tippawangkosol
- School of Allied Health Sciences, Walailak University, Nakhonsithammarat, Thailand
- Department of Parasitology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Pradya Somboon
- Department of Parasitology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
- *Correspondence: Narissara Jariyapan, ; Pradya Somboon,
| | - Paul A. Bates
- Division of Biomedical and Life Sciences, Faculty of Health and Medicine, Lancaster University, Lancaster, United Kingdom
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6
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Jain S, Sahu U, Kumar A, Khare P. Metabolic Pathways of Leishmania Parasite: Source of Pertinent Drug Targets and Potent Drug Candidates. Pharmaceutics 2022; 14:pharmaceutics14081590. [PMID: 36015216 PMCID: PMC9416627 DOI: 10.3390/pharmaceutics14081590] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 07/22/2022] [Accepted: 07/25/2022] [Indexed: 02/04/2023] Open
Abstract
Leishmaniasis is a tropical disease caused by a protozoan parasite Leishmania that is transmitted via infected female sandflies. At present, leishmaniasis treatment mainly counts on chemotherapy. The currently available drugs against leishmaniasis are costly, toxic, with multiple side effects, and limitations in the administration route. The rapid emergence of drug resistance has severely reduced the potency of anti-leishmanial drugs. As a result, there is a pressing need for the development of novel anti-leishmanial drugs with high potency, low cost, acceptable toxicity, and good pharmacokinetics features. Due to the availability of preclinical data, drug repurposing is a valuable approach for speeding up the development of effective anti-leishmanial through pointing to new drug targets in less time, having low costs and risk. Metabolic pathways of this parasite play a crucial role in the growth and proliferation of Leishmania species during the various stages of their life cycle. Based on available genomics/proteomics information, known pathways-based (sterol biosynthetic pathway, purine salvage pathway, glycolysis, GPI biosynthesis, hypusine, polyamine biosynthesis) Leishmania-specific proteins could be targeted with known drugs that were used in other diseases, resulting in finding new promising anti-leishmanial therapeutics. The present review discusses various metabolic pathways of the Leishmania parasite and some drug candidates targeting these pathways effectively that could be potent drugs against leishmaniasis in the future.
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Affiliation(s)
- Surbhi Jain
- Department of Microbiology, All India Institute of Medical Sciences, Bhopal 462026, Madhya Pradesh, India; (S.J.); (U.S.)
| | - Utkarsha Sahu
- Department of Microbiology, All India Institute of Medical Sciences, Bhopal 462026, Madhya Pradesh, India; (S.J.); (U.S.)
- Division of Synthetic Biology, Absolute Foods, Plot 68, Sector 44, Gurugram 122003, Haryana, India
| | - Awanish Kumar
- Department of Biotechnology, National Institute of Technology, Raipur 492010, Chhattisgarh, India
- Correspondence: or (A.K.); (P.K.)
| | - Prashant Khare
- Department of Microbiology, All India Institute of Medical Sciences, Bhopal 462026, Madhya Pradesh, India; (S.J.); (U.S.)
- Division of Synthetic Biology, Absolute Foods, Plot 68, Sector 44, Gurugram 122003, Haryana, India
- Correspondence: or (A.K.); (P.K.)
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7
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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.
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8
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Cecílio P, Cordeiro-da-Silva A, Oliveira F. Sand flies: Basic information on the vectors of leishmaniasis and their interactions with Leishmania parasites. Commun Biol 2022; 5:305. [PMID: 35379881 PMCID: PMC8979968 DOI: 10.1038/s42003-022-03240-z] [Citation(s) in RCA: 53] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 03/08/2022] [Indexed: 11/09/2022] Open
Abstract
Blood-sucking arthropods transmit a variety of human pathogens acting as disseminators of the so-called vector-borne diseases. Leishmaniasis is a spectrum of diseases caused by different Leishmania species, transmitted quasi worldwide by sand flies. However, whereas many laboratories focus on the disease(s) and etiological agents, considerably less study the respective vectors. In fact, information on sand flies is neither abundant nor easy to find; aspects including basic biology, ecology, and sand-fly-Leishmania interactions are usually reported separately. Here, we compile elemental information on sand flies, in the context of leishmaniasis. We discuss the biology, distribution, and life cycle, the blood-feeding process, and the Leishmania-sand fly interactions that govern parasite transmission. Additionally, we highlight some outstanding questions that need to be answered for the complete understanding of parasite–vector–host interactions in leishmaniasis. In this review, numerous aspects of sand flies as vectors of Leishmania parasites—from biology to the vector parasite interactions—are discussed.
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Affiliation(s)
- Pedro Cecílio
- Vector Molecular Biology Section, Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA. .,i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal. .,Parasite Disease Group, IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal. .,Departamento de Ciências Biológicas, Faculdade de Farmácia da Universidade do Porto (FFUP), Porto, Portugal.
| | - Anabela Cordeiro-da-Silva
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal.,Parasite Disease Group, IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal.,Departamento de Ciências Biológicas, Faculdade de Farmácia da Universidade do Porto (FFUP), Porto, Portugal
| | - Fabiano Oliveira
- Vector Molecular Biology Section, Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA.
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Pereira A, Parreira R, Cristóvão JM, Vitale F, Bastien P, Campino L, Maia C. Leishmania infantum strains from cats are similar in biological properties to canine and human strains. Vet Parasitol 2021; 298:109531. [PMID: 34293586 DOI: 10.1016/j.vetpar.2021.109531] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 07/05/2021] [Accepted: 07/11/2021] [Indexed: 11/28/2022]
Abstract
Zoonotic visceral leishmaniosis is a worldwide severe disease caused by Leishmania infantum, a protozoan that has phlebotomine sand flies as vectors and dogs as primary reservoir hosts. Over the last few decades, cats have been regarded as an indisputable piece within the ecological system in which L. infantum is maintained indefinitely. However, little is known about feline strains, including their phenotypic plasticity and infectivity. In this study, the phenotypic behaviour of seven L. infantum feline strains was compared to those of well-characterised counterparts isolated from two dogs and two humans in terms of growth profile, adaptive capacity under several stress conditions, susceptibility to antileishmanial drugs, and infectivity to host cells. Feline strains displayed a similar growth profile, survival capacity, and ability to infect feline, canine, and human monocyte-derived primary macrophages. Furthermore, multivariate cluster analysis suggested that most strains studied did not display distinctive phenotypic features. To our knowledge, this is the first study to analyse the phenotypic behaviour of feline L. infantum strains. This study brings new insights into the hypothetical role of cats as reservoir hosts of L. infantum since the parasites found in them are phenotypically identical to those of dogs and humans. However, further studies on the transmission dynamics should be encouraged to fully establish the status of cats in the maintenance of L. infantum foci.
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Affiliation(s)
- André Pereira
- Global Health and Tropical Medicine (GHMT), Instituto de Higiene e Medicina Tropical (IHMT), Universidade Nova de Lisboa (NOVA), 1349-008, Lisbon, Portugal; Medical Parasitology Unit, IHMT/NOVA, 1349-008, Lisbon, Portugal
| | - Ricardo Parreira
- Global Health and Tropical Medicine (GHMT), Instituto de Higiene e Medicina Tropical (IHMT), Universidade Nova de Lisboa (NOVA), 1349-008, Lisbon, Portugal; Medical Microbiology Unit, IHMT/NOVA, 1349-008, Lisbon, Portugal
| | - José Manuel Cristóvão
- Global Health and Tropical Medicine (GHMT), Instituto de Higiene e Medicina Tropical (IHMT), Universidade Nova de Lisboa (NOVA), 1349-008, Lisbon, Portugal; Medical Parasitology Unit, IHMT/NOVA, 1349-008, Lisbon, Portugal
| | - Fabrizio Vitale
- OIE Leishmaniasis Reference Laboratory, Istituto Zooprofilattico Sperimentale della Sicilia, 90129, Palermo, Italy
| | - Patrick Bastien
- University of Montpellier, CNRS, IRD, Research Unit "MIVEGEC", Centre National de Reference pour les Leishmanioses, Academic Hospital (C.H.U.) of Montpellier, 34090, Montpellier, France
| | - Lenea Campino
- Medical Parasitology Unit, IHMT/NOVA, 1349-008, Lisbon, Portugal
| | - Carla Maia
- Global Health and Tropical Medicine (GHMT), Instituto de Higiene e Medicina Tropical (IHMT), Universidade Nova de Lisboa (NOVA), 1349-008, Lisbon, Portugal; Medical Parasitology Unit, IHMT/NOVA, 1349-008, Lisbon, Portugal.
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10
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Rico-Jiménez M, Ceballos-Pérez G, Gómez-Liñán C, Estévez AM. An RNA-binding protein complex regulates the purine-dependent expression of a nucleobase transporter in trypanosomes. Nucleic Acids Res 2021; 49:3814-3825. [PMID: 33744953 PMCID: PMC8053114 DOI: 10.1093/nar/gkab181] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Revised: 03/02/2021] [Accepted: 03/04/2021] [Indexed: 12/13/2022] Open
Abstract
Post-transcriptional regulation of gene expression is particularly important in trypanosomatid protozoa. RNA-binding proteins (RBPs) regulate mRNA stability and translation, yet information about how RBPs are able to link environmental cues to post-transcriptional control is scarce. In Trypanosoma brucei, we have previously characterized a short RNA stem-loop cis-element (PuRE, Purine Responsive Element) within the 3'-UTR of the NT8 nucleobase transporter mRNA that is necessary and sufficient to confer a strong repression of gene expression in response to purines. In this study, we have identified a protein complex composed of two RNA-binding proteins (PuREBP1 and PuREBP2) that binds to the PuRE in vitro and to NT8 mRNA in vivo. Depletion of PuREBP1 by RNA interference results in the upregulation of just NT8 and the mRNAs encoding the amino acid transporter AATP6 paralogues. Moreover, we found that the PuREBP1/2 complex is associated with only a handful of mRNAs, and that it is responsible for the observed purine-dependent regulation of NT8 expression.
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Affiliation(s)
- Miriam Rico-Jiménez
- Instituto de Parasitología y Biomedicina 'López-Neyra', IPBLN-CSIC, Parque Tecnológico de Ciencias de la Salud, Avda. del Conocimiento 17, 18016 Armilla, Granada, Spain
| | - Gloria Ceballos-Pérez
- Instituto de Parasitología y Biomedicina 'López-Neyra', IPBLN-CSIC, Parque Tecnológico de Ciencias de la Salud, Avda. del Conocimiento 17, 18016 Armilla, Granada, Spain
| | - Claudia Gómez-Liñán
- Instituto de Parasitología y Biomedicina 'López-Neyra', IPBLN-CSIC, Parque Tecnológico de Ciencias de la Salud, Avda. del Conocimiento 17, 18016 Armilla, Granada, Spain
| | - Antonio M Estévez
- Instituto de Parasitología y Biomedicina 'López-Neyra', IPBLN-CSIC, Parque Tecnológico de Ciencias de la Salud, Avda. del Conocimiento 17, 18016 Armilla, Granada, Spain
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Lemos-Silva T, Telleria EL, Traub-Csekö YM. The gene expression of Leishmania infantum chagasi inside Lutzomyia longipalpis, the main vector of visceral leishmaniasis in Brazil. Mem Inst Oswaldo Cruz 2021; 116:e200571. [PMID: 33681890 PMCID: PMC7949195 DOI: 10.1590/0074-02760200571] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Accepted: 02/08/2021] [Indexed: 11/21/2022] Open
Abstract
Leishmania infantum chagasi is the causative agent and Lutzomyia longipalpis is the main vector of visceral leishmaniasis in the Americas. We investigated the expression of Leishmania genes within L. longipalpis after artificial infection. mRNAs from genes involved in sugar and amino acid metabolism were upregulated at times of high parasite proliferation inside the insect. mRNAs from genes involved in metacyclogenesis had higher expression in late stages of infection. Other modulated genes of interest were involved in immunomodulation, purine salvage pathway and protein recycling. These data reveal aspects of the adaptation of the parasite to the microenvironment of the vector gut and reflect the preparation for infection in the vertebrate.
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Affiliation(s)
- Thais Lemos-Silva
- Fundação Oswaldo Cruz-Fiocruz, Instituto Oswaldo Cruz, Laboratório de Biologia Molecular de Parasitas e Vetores, Rio de Janeiro, RJ, Brasil
| | - Erich Loza Telleria
- Fundação Oswaldo Cruz-Fiocruz, Instituto Oswaldo Cruz, Laboratório de Biologia Molecular de Parasitas e Vetores, Rio de Janeiro, RJ, Brasil.,Charles University, Faculty of Science, Department of Parasitology, Prague, Czech Republic
| | - Yara Maria Traub-Csekö
- Fundação Oswaldo Cruz-Fiocruz, Instituto Oswaldo Cruz, Laboratório de Biologia Molecular de Parasitas e Vetores, Rio de Janeiro, RJ, Brasil
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12
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Kelly FD, Yates PA, Landfear SM. Nutrient sensing in Leishmania: Flagellum and cytosol. Mol Microbiol 2020; 115:849-859. [PMID: 33112443 DOI: 10.1111/mmi.14635] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 10/23/2020] [Accepted: 10/25/2020] [Indexed: 12/18/2022]
Abstract
Parasites are by definition organisms that utilize resources from a host to support their existence, thus, promoting their ability to establish long-term infections and disease. Hence, sensing and acquiring nutrients for which the parasite and host compete is central to the parasitic mode of existence. Leishmania are flagellated kinetoplastid parasites that parasitize phagocytic cells, principally macrophages, of vertebrate hosts and the alimentary tract of sand fly vectors. Because nutritional supplies vary over time within both these hosts and are often restricted in availability, these parasites must sense a plethora of nutrients and respond accordingly. The flagellum has been recognized as an "antenna" that plays a core role in sensing environmental conditions, and various flagellar proteins have been implicated in sensing roles. In addition, these parasites exhibit non-flagellar intracellular mechanisms of nutrient sensing, several of which have been explored. Nonetheless, mechanistic details of these sensory pathways are still sparse and represent a challenging frontier for further experimental exploration.
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Affiliation(s)
- Felice D Kelly
- Department of Molecular Microbiology & Immunology, Oregon Health & Science University, Portland, OR, USA
| | - Phillip A Yates
- Department of Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, OR, USA
| | - Scott M Landfear
- Department of Molecular Microbiology & Immunology, Oregon Health & Science University, Portland, OR, USA
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13
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Licon MH, Yates PA. Purine-responsive expression of the Leishmania donovani NT3 purine nucleobase transporter is mediated by a conserved RNA stem-loop. J Biol Chem 2020; 295:8449-8459. [PMID: 32354744 PMCID: PMC7307198 DOI: 10.1074/jbc.ra120.012696] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2020] [Revised: 04/28/2020] [Indexed: 01/17/2023] Open
Abstract
The ability to modulate gene expression in response to changes in the host environment is essential for survival of the kinetoplastid parasite Leishmania Unlike most eukaryotes, gene expression in kinetoplastids is predominately regulated posttranscriptionally. Consequently, RNA-binding proteins and mRNA-encoded sequence elements serve as primary determinants of gene regulation in these organisms; however, few have defined roles in specific stress response pathways. Leishmania species cannot synthesize purines de novo and must scavenge these essential nutrients from the host. Leishmania have evolved a robust stress response to withstand sustained periods of purine scarcity during their life cycle. The purine nucleobase transporter LdNT3 is among the most substantially up-regulated proteins in purine-starved Leishmania donovani parasites. Here we report that the posttranslational stability of the LdNT3 protein is unchanged in response to purine starvation. Instead, LdNT3 up-regulation is primarily mediated by a 33-nucleotide-long sequence in the LdNT3 mRNA 3' UTR that is predicted to adopt a stem-loop structure. Although this sequence is highly conserved within the mRNAs of orthologous transporters in multiple kinetoplastid species, putative stem-loops from L. donovani and Trypanosoma brucei nucleobase transporter mRNAs were not functionally interchangeable for purine-responsive regulation. Through mutational analysis of the element, we demonstrate that species specificity is attributable to just three variant bases within the predicted loop. Finally, we provide evidence that the abundance of the trans-acting factor that binds the LdNT3 stem-loop in vivo is substantially higher than required for regulation of LdNT3 alone, implying a potential role in regulating other purine-responsive genes.
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Affiliation(s)
- M Haley Licon
- Department of Molecular Microbiology, Oregon Health & Science University, Portland, Oregon, USA
| | - Phillip A Yates
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, Oregon, USA
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14
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Rocha VPC, Dacher M, Young SA, Kolokousi F, Efstathiou A, Späth GF, Soares MBP, Smirlis D. Leishmania dual-specificity tyrosine-regulated kinase 1 (DYRK1) is required for sustaining Leishmania stationary phase phenotype. Mol Microbiol 2020; 113:983-1002. [PMID: 31975452 DOI: 10.1111/mmi.14464] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 01/13/2020] [Accepted: 01/16/2020] [Indexed: 01/05/2023]
Abstract
Although the multiplicative and growth-arrested states play key roles in Leishmania development, the regulators of these transitions are largely unknown. In an attempt to gain a better understanding of these processes, we characterised one member of a family of protein kinases with dual specificity, LinDYRK1, which acts as a stasis regulator in other organisms. LinDYRK1 overexpressing parasites displayed a decrease in proliferation and in cell cycle re-entry of arrested cells. Parasites lacking LinDYRK1 displayed distinct fitness phenotypes in logarithmic and stationary growth phases. In logarithmic growth phase, LinDYRK1-/- parasites proliferated better than control lines, supporting a role of this kinase in stasis, while in stationary growth phase, LinDYRK1-/- parasites had important defects as they rounded up, accumulated vacuoles and lipid bodies and displayed subtle but consistent differences in lipid composition. Moreover, they expressed less metacyclic-enriched transcripts, displayed increased sensitivity to complement lysis and a significant reduction in survival within peritoneal macrophages. The distinct LinDYRK1-/- growth phase phenotypes were mirrored by the distinct LinDYRK1 localisations in logarithmic (mainly in flagellar pocket area and endosomes) and late stationary phase (mitochondrion). Overall, this work provides first evidence for the role of a DYRK family member in sustaining promastigote stationary phase phenotype and infectivity.
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Affiliation(s)
- Vinícius Pinto Costa Rocha
- Instituto Gonçalo Moniz, Fundação Oswaldo Cruz (FIOCRUZ), Salvador, Brazil
- Centro de Biotecnologia e Terapia Celular, Hospital São Rafael, Salvador, Brazil
| | - Mariko Dacher
- Unité de Parasitologie Moléculaire et Signalisation, Department of Parasites and Insect Vectors, Institut Pasteur and INSERM U1201, Paris, France
| | - Simon Alan Young
- Biomedical Sciences Research Complex, School of Biology, The University of St. Andrews, St. Andrews, UK
| | - Foteini Kolokousi
- Molecular Parasitology Laboratory, Microbiology Department, Hellenic Pasteur Institute, Athens, Greece
| | - Antonia Efstathiou
- Molecular Parasitology Laboratory, Microbiology Department, Hellenic Pasteur Institute, Athens, Greece
| | - Gerald Frank Späth
- Unité de Parasitologie Moléculaire et Signalisation, Department of Parasites and Insect Vectors, Institut Pasteur and INSERM U1201, Paris, France
| | - Milena Botelho Pereira Soares
- Instituto Gonçalo Moniz, Fundação Oswaldo Cruz (FIOCRUZ), Salvador, Brazil
- Centro de Biotecnologia e Terapia Celular, Hospital São Rafael, Salvador, Brazil
| | - Despina Smirlis
- Molecular Parasitology Laboratory, Microbiology Department, Hellenic Pasteur Institute, Athens, Greece
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15
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Regulation of Translation in the Protozoan Parasite Leishmania. Int J Mol Sci 2020; 21:ijms21082981. [PMID: 32340274 PMCID: PMC7215931 DOI: 10.3390/ijms21082981] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 04/16/2020] [Accepted: 04/20/2020] [Indexed: 01/31/2023] Open
Abstract
Leishmaniasis represents a serious health problem worldwide and drug resistance is a growing concern. Leishmania parasites use unusual mechanisms to control their gene expression. In contrast to many other species, they do not have transcriptional regulation. The lack of transcriptional control is mainly compensated by post-transcriptional mechanisms, including tight translational control and regulation of mRNA stability/translatability by RNA-binding proteins. Modulation of translation plays a major role in parasite survival and adaptation to dramatically different environments during change of host; however, our knowledge of fine molecular mechanisms of translation in Leishmania remains limited. Here, we review the current progress in our understanding of how changes in the translational machinery promote parasite differentiation during transmission from a sand fly to a mammalian host, and discuss how translational reprogramming can contribute to the development of drug resistance.
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16
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Ong HB, Clare S, Roberts AJ, Wilson ME, Wright GJ. Establishment, optimisation and quantitation of a bioluminescent murine infection model of visceral leishmaniasis for systematic vaccine screening. Sci Rep 2020; 10:4689. [PMID: 32170135 PMCID: PMC7070049 DOI: 10.1038/s41598-020-61662-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 02/27/2020] [Indexed: 02/08/2023] Open
Abstract
Visceral leishmaniasis is an infectious parasitic disease caused by the protozoan parasites Leishmania donovani and Leishmania infantum. The drugs currently used to treat visceral leishmaniasis suffer from toxicity and the emergence of parasite resistance, and so a better solution would be the development of an effective subunit vaccine; however, no approved vaccine currently exists. The comparative testing of a large number of vaccine candidates requires a quantitative and reproducible experimental murine infection model, but the parameters that influence infection pathology have not been systematically determined. To address this, we have established an infection model using a transgenic luciferase-expressing L. donovani parasite and longitudinally quantified the infections using in vivo bioluminescent imaging within individual mice. We examined the effects of varying the infection route, the site of adjuvant formulation administration, and standardised the parasite preparation and dose. We observed that the increase in parasite load within the liver during the first few weeks of infection was directly proportional to the parasite number in the initial inoculum. Finally, we show that immunity can be induced in pre-exposed animals that have resolved an initial infection. This murine infection model provides a platform for systematic subunit vaccine testing against visceral leishmaniasis.
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Affiliation(s)
- Han Boon Ong
- Cell Surface Signalling Laboratory, Wellcome Sanger Institute, Cambridge, UK
| | - Simon Clare
- Pathogen Laboratory Support, Wellcome Sanger Institute, Cambridge, UK
| | | | - Mary Edythe Wilson
- Departments of Microbiology and Immunology and Internal Medicine, University of Iowa, and the Iowa City Veterans' Affairs Medical Center, Iowa City, USA
| | - Gavin James Wright
- Cell Surface Signalling Laboratory, Wellcome Sanger Institute, Cambridge, UK.
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17
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Campagnaro GD, de Koning HP. Purine and pyrimidine transporters of pathogenic protozoa - conduits for therapeutic agents. Med Res Rev 2020; 40:1679-1714. [PMID: 32144812 DOI: 10.1002/med.21667] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 02/12/2020] [Accepted: 02/18/2020] [Indexed: 02/06/2023]
Abstract
Purines and pyrimidines are essential nutrients for any cell. Most organisms are able to synthesize their own purines and pyrimidines, but this ability was lost in protozoans that adapted to parasitism, leading to a great diversification in transporter activities in these organisms, especially for the acquisition of amino acids and nucleosides from their hosts throughout their life cycles. Many of these transporters have been shown to have sufficiently different substrate affinities from mammalian transporters, making them good carriers for therapeutic agents. In this review, we summarize the knowledge obtained on purine and pyrimidine activities identified in protozoan parasites to date and discuss their importance for the survival of these parasites and as drug carriers, as well as the perspectives of developments in the field.
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Affiliation(s)
- Gustavo D Campagnaro
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, 120 University Place, Glasgow, UK
| | - Harry P de Koning
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, 120 University Place, Glasgow, UK
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18
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A quantitative proteomic and bioinformatics analysis of proteins in metacyclogenesis of Leishmania tropica. Acta Trop 2020; 202:105227. [PMID: 31647897 DOI: 10.1016/j.actatropica.2019.105227] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 10/07/2019] [Accepted: 10/18/2019] [Indexed: 02/07/2023]
Abstract
Recently there has a growing interest in MS-based analysis on Leishmania for biology study, host-parasite interaction and drug target discovery. The aims of this study were to analyzed protein profiles in the procyclic and metacyclic stages of L. tropica, and investigate their potential role in metacyclogenesis molecular mechanisms. Sequential window acquisition of all theoretical fragment ion spectra mass spectrometry (SWATH-MS) analysis was used to analyze protein profiles in each of procyclic and metacyclic stages. Proteins with a fold change>2 or <0.5 and p < 0.05 were considered to be significantly differentially expressed proteins (DEPs). The DEPs were subjected to gene ontology (GO), KEGG pathway and network analysis using PANTHER and STRING database, respectively. Quantitative real-time PCR of six selected genes validated the proteomic data. We quantified a total of 352 proteins in procyclic and metacyclic cells and 56 differentially expressed proteins (27 up/ 29down-regulated in metacyclic compared to procyclic). On the basis of biological processes in GO, the DEPs were primarily involved in ``metabolic process'' (GO: 0008152) and ``cellular process'' (GO: 0009987). In addition, several enriched GO terms were identified via molecular function, which among them ``catalytic activity'' (GO: 0003824) and ``binding'' (GO: 0005488) were disclosed as top category. The KEGG pathway analysis indicated ``metabolic pathways'' (p-value: 3.80E-08) including 17 genes term as the top pathway in DEPs. These findings bring a new insight in our understanding of the molecular characterization of metacyclogenesis and infective form in L. tropica. Comparative analysis of the proteome of both developmental stages of the L. tropica would help to the identification of proteins candidates for the development of new potential drug targets and vaccines.
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19
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Deletion of a Single LeishIF4E-3 Allele by the CRISPR-Cas9 System Alters Cell Morphology and Infectivity of Leishmania. mSphere 2019; 4:4/5/e00450-19. [PMID: 31484740 PMCID: PMC6731530 DOI: 10.1128/msphere.00450-19] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Leishmania species are the causative agents of a spectrum of diseases. Available drug treatment is toxic and expensive, with drug resistance a growing concern. Leishmania parasites migrate between transmitting sand flies and mammalian hosts, experiencing unfavorable extreme conditions. The parasites therefore developed unique mechanisms for promoting a stage-specific program for gene expression, with translation playing a central role. There are six paralogs of the cap-binding protein eIF4E, which vary in their function, expression profiles, and assemblages. Using the CRISPR-Cas9 system for Leishmania, we deleted one of the two LeishIF4E-3 alleles. Expression of LeishIF4E-3 in the deletion mutant was low, leading to reduction in global translation and growth of the mutant cells. Cell morphology also changed, affecting flagellum growth, cell shape, and infectivity. The importance of this study is in highlighting that LeishIF4E-3 is essential for completion of the parasite life cycle. Our study gives new insight into how parasite virulence is determined. The genomes of Leishmania and trypanosomes encode six paralogs of the eIF4E cap-binding protein, known in other eukaryotes to anchor the translation initiation complex. In line with the heteroxenous nature of these parasites, the different LeishIF4E paralogs vary in their biophysical features and their biological behavior. We therefore hypothesize that each has a specialized function, not limited to protein synthesis. Of the six paralogs, LeishIF4E-3 has a weak cap-binding activity. It participates in the assembly of granules that store inactive transcripts and ribosomal proteins during nutritional stress that is experienced in the sand fly. We investigated the role of LeishIF4E-3 in Leishmania mexicana promastigotes using the CRISPR-Cas9 system. We deleted one of the two LeishIF4E-3 alleles, generating a heterologous deletion mutant with reduced LeishIF4E-3 expression. The mutant showed a decline in de novo protein synthesis and growth kinetics, altered morphology, and impaired infectivity. The mutant cells were rounded and failed to transform into the nectomonad-like form, in response to purine starvation. Furthermore, the infectivity of macrophage cells by the LeishIF4E-3(+/−) mutant was severely reduced. These phenotypic features were not observed in the addback cells, in which expression of LeishIF4E-3 was restored. The observed phenotypic changes correlated with the profile of transcripts associated with LeishIF4E-3. These were enriched for cytoskeleton- and flagellum-encoding genes, along with genes for RNA binding proteins. Our data illustrate the importance of LeishIF4E-3 in translation and in the parasite virulence. IMPORTANCELeishmania species are the causative agents of a spectrum of diseases. Available drug treatment is toxic and expensive, with drug resistance a growing concern. Leishmania parasites migrate between transmitting sand flies and mammalian hosts, experiencing unfavorable extreme conditions. The parasites therefore developed unique mechanisms for promoting a stage-specific program for gene expression, with translation playing a central role. There are six paralogs of the cap-binding protein eIF4E, which vary in their function, expression profiles, and assemblages. Using the CRISPR-Cas9 system for Leishmania, we deleted one of the two LeishIF4E-3 alleles. Expression of LeishIF4E-3 in the deletion mutant was low, leading to reduction in global translation and growth of the mutant cells. Cell morphology also changed, affecting flagellum growth, cell shape, and infectivity. The importance of this study is in highlighting that LeishIF4E-3 is essential for completion of the parasite life cycle. Our study gives new insight into how parasite virulence is determined.
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20
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Shrivastava R, Drory-Retwitzer M, Shapira M. Nutritional stress targets LeishIF4E-3 to storage granules that contain RNA and ribosome components in Leishmania. PLoS Negl Trop Dis 2019; 13:e0007237. [PMID: 30870425 PMCID: PMC6435199 DOI: 10.1371/journal.pntd.0007237] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2018] [Revised: 03/26/2019] [Accepted: 02/12/2019] [Indexed: 12/02/2022] Open
Abstract
Leishmania parasites lack pathways for de novo purine biosynthesis. The depletion of purines induces differentiation into virulent metacyclic forms. In vitro, the parasites can survive prolonged periods of purine withdrawal changing their morphology to long and slender cells with an extended flagellum, and decreasing their translation rates. Reduced translation leads to the appearance of discrete granules that contain LeishIF4E-3, one of the six eIF4E paralogs encoded by the Leishmania genome. We hypothesize that each is responsible for a different function during the life cycle. LeishIF4E-3 is a weak cap-binding protein paralog, but its involvement in translation under normal conditions cannot be excluded. However, in response to nutritional stress, LeishIF4E-3 concentrates in specific cytoplasmic granules. LeishIF4E-3 granulation can be induced by the independent elimination of purines, amino acids and glucose. As these granules contain mature mRNAs, we propose that these bodies store inactive transcripts until recovery from stress occurs. In attempt to examine the content of the nutritional stress-induced granules, they were concentrated over sucrose gradients and further pulled-down by targeting in vivo tagged LeishIF4E-3. Proteomic analysis highlighted granule enrichment with multiple ribosomal proteins, suggesting that ribosome particles are abundant in these foci, as expected in case of translation inhibition. RNA-binding proteins, RNA helicases and metabolic enzymes were also enriched in the granules, whereas no degradation enzymes or P-body markers were detected. The starvation-induced LeishIF4E-3-containing granules, therefore, appear to store stalled ribosomes and ribosomal subunits, along with their associated mRNAs. Following nutritional stress, LeishIF4E-3 becomes phosphorylated at position S75, located in its less-conserved N-terminal extension. The ability of the S75A mutant to form granules was reduced, indicating that cellular signaling regulates LeishIF4E-3 function. Cells respond to cellular stress by decreasing protein translation, to prevent the formation of partially folded or misfolded new polypeptides whose accumulation can be detrimental to living cells. Under such conditions, the cells benefit from storing inactive mRNAs and stalled ribosomal particles, to maintain their availability once conditions improve; dedicated granules offer a solution for such storage. Leishmania parasites are exposed to a variety of stress conditions as a natural part of their life cycle, including the nutritional stress that the parasites experience within the gut of the sandfly. Thus, Leishmania and related trypanosomatids serve as a good model system to investigate RNA fate during different stress conditions. Various granules appear in Leishmania and related organisms in response to different stress conditions. Here, we investigated how nutritional stress, in particular elimination of purines, induced the formation of granules that harbor a specific cap-binding protein, LeishIF4E-3. The starvation-induced LeishIF4E-3 containing granules consist of a variety of ribosomal proteins, along with RNA-binding proteins and mature mRNAs. We thus propose that Leishmania modulates the assembly of LeishIF4E-3-containing granules for transient storage of stalled ribosomal particles and inactive mRNAs. Following renewal of nutrient availability, as occurs during the parasite’s life cycle, the granules disappear. Although their fate is yet unclear, they could be recycled in the cell. Unlike other granules described in trypanosomes, the LeishIF4E-3-containing granules did not contain RNA degradation enzymes, suggesting that their function is mainly for storage until conditions improve.
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Affiliation(s)
- Rohit Shrivastava
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Matan Drory-Retwitzer
- Department of Computer Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Michal Shapira
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
- * E-mail:
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21
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Metacyclogenesis of Leishmania (Viannia) guyanensis: a comprehensive study of the main transformation features in axenic culture and purification of metacyclic promastigotes by negative selection with Bauhinia purpurea lectin. Parasitology 2018; 146:716-727. [PMID: 30588899 DOI: 10.1017/s0031182018002111] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Leishmania (Viannia) guyanensis is one species that causes cutaneous leishmaniasis in the New World. The incidence of infections with this parasite is probably underestimated and few studies exist on this species, despite its epidemiological importance. In particular, there are no studies concerning L. guyanensis metacyclogenesis and no technique for obtaining metacyclic promastigotes for this species is presently available. Here, we have studied L. guyanensis metacyclogenesis in axenic culture, describing the main changes that occur during this process, namely, in morphology and size, sensitivity to complement-mediated lysis, surface carbohydrates and infectivity to macrophages. We have shown that metacyclogenesis in L. guyanensis promastigotes is basically complete on the 4th day of culture, as determined by decreased body size, increased flagellum length, resistance to complement-mediated lysis and infectivity. We have also found that only a fraction of the parasites is agglutinated by Bauhinia purpurea lectin. The non-agglutinated parasites, which also peaked on the 4th day of culture, had all morphological traits typical of the metacyclic stage. This is the first report describing metacyclogenesis in L. guyanensis axenic promastigotes and a simple and efficient method for the purification of metacyclic forms. Furthermore, a model of human macrophage infection with L. guyanensis was established.
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22
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Serafim TD, Coutinho-Abreu IV, Oliveira F, Meneses C, Kamhawi S, Valenzuela JG. Sequential blood meals promote Leishmania replication and reverse metacyclogenesis augmenting vector infectivity. Nat Microbiol 2018; 3:548-555. [PMID: 29556108 PMCID: PMC6007031 DOI: 10.1038/s41564-018-0125-7] [Citation(s) in RCA: 94] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 02/08/2018] [Indexed: 12/16/2022]
Abstract
Sand flies, similar to most vectors, take multiple blood meals during their lifetime1-4. The effect of subsequent blood meals on pathogens developing in the vector and their impact on disease transmission have never been examined. Here, we show that ingestion of a second uninfected blood meal by Leishmania-infected sand flies triggers dedifferentiation of metacyclic promastigotes, considered a terminally differentiated stage inside the vector 5 , to a leptomonad-like stage, the retroleptomonad promastigote. Reverse metacyclogenesis occurs after every subsequent blood meal where retroleptomonad promastigotes rapidly multiply and differentiate to metacyclic promastigotes enhancing sand fly infectiousness. Importantly, a subsequent blood meal amplifies the few Leishmania parasites acquired by feeding on infected hosts by 125-fold, and increases lesion frequency by fourfold, in twice-fed compared with single-fed flies. These findings place readily available blood sources as a critical element in transmission and propagation of vector-borne pathogens.
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Affiliation(s)
- Tiago D Serafim
- Vector Molecular Biology Section, Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Iliano V Coutinho-Abreu
- Vector Molecular Biology Section, Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Fabiano Oliveira
- Vector Molecular Biology Section, Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Claudio Meneses
- Vector Molecular Biology Section, Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Shaden Kamhawi
- Vector Molecular Biology Section, Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA.
| | - Jesus G Valenzuela
- Vector Molecular Biology Section, Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA.
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23
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Peres NTDA, Cunha LCS, Barbosa MLA, Santos MB, de Oliveira FA, de Jesus AMR, de Almeida RP. Infection of Human Macrophages by Leishmania infantum Is Influenced by Ecto-Nucleotidases. Front Immunol 2018; 8:1954. [PMID: 29379503 PMCID: PMC5770793 DOI: 10.3389/fimmu.2017.01954] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Accepted: 12/18/2017] [Indexed: 12/20/2022] Open
Abstract
Ecto-nucleotidase activity is involved in the infection process of Leishmania and various other parasites that enables modulation of host immune responses to promote disease progression. One of the enzymes responsible for this activity is the ecto-nucleoside triphosphate diphosphohydrolase (E-NTPDase). The enzyme hydrolyzes nucleotides tri- and/or di-phosphate into monophosphate products, which are subsequently hydrolyzed into adenosine. These nucleotides can serve as purinergic signaling molecules involved in diverse cellular processes that govern immune responses. Given the importance of the extracellular metabolism of these nucleotides during intracellular pathogen infections, this study evaluates the role of ecto-nucleotidase activity during Leishmania infantum (L. infantum) infection in human macrophages. E-NTPDase protein expression and activity was evaluated in L. infantum during purine starvation, adenosine-enriched medium, or in the presence of an inhibitor of ecto-nucleotidases. Results show that E-NTPDase is expressed in L. infantum parasites, including on the cell membrane. Furthermore, functional activity of the enzyme was modulated according to the availability of adenosine in the medium. Purine starvation increased the hydrolytic capacity of nucleotides leading to higher infectivity, while growth in adenosine-enriched medium led to lower infectivity. Moreover, inhibiting E-NTPDase function decreased L. infantum infection in macrophages, suggesting the enzyme may serve as a ligand. Taken together, the ability of L. infantum to hydrolyze nucleotides is directly associated with increased infectivity in macrophages.
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Affiliation(s)
- Nalu Teixeira de Aguiar Peres
- Laboratory of Molecular Biology, Department of Medicine, University Hospital, Federal University of Sergipe, São Cristóvão, Brazil.,Department of Morphology, Biological and Health Sciences Centre, Federal University of Sergipe, Aracaju, Brazil
| | - Luana Celina Seraphim Cunha
- Laboratory of Molecular Biology, Department of Medicine, University Hospital, Federal University of Sergipe, São Cristóvão, Brazil
| | - Meirielly Lima Almeida Barbosa
- Laboratory of Molecular Biology, Department of Medicine, University Hospital, Federal University of Sergipe, São Cristóvão, Brazil
| | - Márcio Bezerra Santos
- Laboratory of Molecular Biology, Department of Medicine, University Hospital, Federal University of Sergipe, São Cristóvão, Brazil.,Department of Health Science, Federal University of Sergipe, Aracaju, Brazil
| | - Fabrícia Alvise de Oliveira
- Laboratory of Molecular Biology, Department of Medicine, University Hospital, Federal University of Sergipe, São Cristóvão, Brazil
| | - Amélia Maria Ribeiro de Jesus
- Laboratory of Molecular Biology, Department of Medicine, University Hospital, Federal University of Sergipe, São Cristóvão, Brazil.,Instituto de Investigação em Imunologia, Institutos Nacionais de Ciência e Tecnologia, Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Brasília, Brazil
| | - Roque Pacheco de Almeida
- Laboratory of Molecular Biology, Department of Medicine, University Hospital, Federal University of Sergipe, São Cristóvão, Brazil.,Instituto de Investigação em Imunologia, Institutos Nacionais de Ciência e Tecnologia, Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Brasília, Brazil
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Azzouz S, Lawton P. In vitro effects of purine and pyrimidine analogues on Leishmania donovani and Leishmania infantum promastigotes and intracellular amastigotes. Acta Parasitol 2017; 62:582-588. [PMID: 28682767 DOI: 10.1515/ap-2017-0070] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 04/26/2017] [Indexed: 01/19/2023]
Abstract
Inhibition of parasite metabolic pathways is a rationale for new chemotherapeutic strategies. The pyrimidine and purine salvage pathways are thus targets against Leishmania donovani and L. infantum, causative agents of visceral human leishmaniasis and canine leishmaniosis. The antiproliferative effect of the pyrimidine analogues Cytarabine and 5-fluorouracil and of the purine analogues Azathioprine and 6-mercaptopurine was evaluated in vitro on the promastigote and the intracellular amastigote stages of the parasite. Cytarabine and 5-fluorouracil were the best inhibitors against promastigotes, whereas 5- fluorouracil and azathioprine displayed the best efficacy against the amastigote stage. The ultrastructural study showed an important cytoplasmic vacuolization and with azathioprine and 5-fluorouracyl, a mitochondrial swelling and appearance of autophagosome-like structures. Alterations of the kinetoplast were also observed with 5-fluorouracil, all these damages eventually resulting in an autolysis process that triggered the subsequent death of the intracellular parasites.
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Louradour I, Monteiro CC, Inbar E, Ghosh K, Merkhofer R, Lawyer P, Paun A, Smelkinson M, Secundino N, Lewis M, Erram D, Zurek L, Sacks D. The midgut microbiota plays an essential role in sand fly vector competence for Leishmania major. Cell Microbiol 2017; 19. [PMID: 28580630 DOI: 10.1111/cmi.12755] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 05/24/2017] [Accepted: 06/01/2017] [Indexed: 11/29/2022]
Abstract
For many arthropod vectors, the diverse bacteria and fungi that inhabit the gut can negatively impact pathogen colonization. Our attempts to exploit antibiotic treatment of colonized Phlebotomus duboscqi sand flies in order to improve their vector competency for Leishmania major resulted instead in flies that were refractory to the development of transmissible infections due to the inability of the parasite to survive and to colonize the anterior midgut with infective, metacyclic stage promastigotes. The parasite survival and development defect could be overcome by feeding the flies on different symbiont bacteria but not by feeding them on bacterial supernatants or replete medium. The inhibitory effect of the dysbiosis was moderated by lowering the concentration of sucrose (<30% w/v) used in the sugar feeds to maintain the colony. Exposure of promastigotes to 30% sucrose was lethal to the parasite in vitro. Confocal imaging revealed that the killing in vivo was confined to promastigotes that had migrated to the anterior plug region, corresponding to the highest concentrations of sucrose. The data suggest that sucrose utilization by the microbiota is essential to promote the appropriate osmotic conditions required for the survival of infective stage promastigotes in vivo.
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Affiliation(s)
- Isabelle Louradour
- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institute of Health, Bethesda, MD, USA
| | - Carolina Cunha Monteiro
- Laboratory of Medical Entomology, Centro de Pesquisas René Rachou, FIOCRUZ, Belo Horizonte, MG, Brazil
| | - Ehud Inbar
- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institute of Health, Bethesda, MD, USA
| | - Kashinath Ghosh
- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institute of Health, Bethesda, MD, USA
| | - Richard Merkhofer
- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institute of Health, Bethesda, MD, USA
| | - Phillip Lawyer
- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institute of Health, Bethesda, MD, USA
| | - Andrea Paun
- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institute of Health, Bethesda, MD, USA
| | - Margery Smelkinson
- Biological Imaging Section, Research Technologies Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Nagila Secundino
- Laboratory of Medical Entomology, Centro de Pesquisas René Rachou, FIOCRUZ, Belo Horizonte, MG, Brazil
| | - Michael Lewis
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, London, UK
| | - Dinesh Erram
- Department of Entomology, Kansas State University, Manhattan, KS, USA
| | - Ludek Zurek
- Department of Entomology, Kansas State University, Manhattan, KS, USA
| | - David Sacks
- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institute of Health, Bethesda, MD, USA
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The Gut Microbiome of the Vector Lutzomyia longipalpis Is Essential for Survival of Leishmania infantum. mBio 2017; 8:mBio.01121-16. [PMID: 28096483 PMCID: PMC5241394 DOI: 10.1128/mbio.01121-16] [Citation(s) in RCA: 87] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
The vector-borne disease leishmaniasis, caused by Leishmania species protozoa, is transmitted to humans by phlebotomine sand flies. Development of Leishmania to infective metacyclic promastigotes in the insect gut, a process termed metacyclogenesis, is an essential prerequisite for transmission. Based on the hypothesis that vector gut microbiota influence the development of virulent parasites, we sequenced midgut microbiomes in the sand fly Lutzomyia longipalpis with or without Leishmania infantum infection. Sucrose-fed sand flies contained a highly diverse, stable midgut microbiome. Blood feeding caused a decrease in microbial richness that eventually recovered. However, bacterial richness progressively decreased in L. infantum-infected sand flies. Acetobacteraceae spp. became dominant and numbers of Pseudomonadaceae spp. diminished coordinately as the parasite underwent metacyclogenesis and parasite numbers increased. Importantly, antibiotic-mediated perturbation of the midgut microbiome rendered sand flies unable to support parasite growth and metacyclogenesis. Together, these data suggest that the sand fly midgut microbiome is a critical factor for Leishmania growth and differentiation to its infective state prior to disease transmission. Leishmania infantum, a parasitic protozoan causing fatal visceral leishmaniasis, is transmitted to humans through the bite of the sand fly Lutzomyia longipalpis. Development of the parasite to its virulent metacyclic state occurs in the sand fly gut. In this study, the microbiota within the Lu. longipalpis midgut was delineated by 16S ribosomal DNA (rDNA) sequencing, revealing a highly diverse community composition that lost diversity as parasites developed to their metacyclic state and increased in abundance in infected flies. Perturbing sand fly gut microbiota with an antibiotic cocktail, which alone had no effect on either the parasite or the fly, arrested both the development of virulent parasites and parasite expansion. These findings indicate the importance of bacterial commensals within the insect vector for the development of virulent pathogens, and raise the possibility that impairing the microbial composition within the vector might represent a novel approach to control of vector-borne diseases.
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Developmental differentiation in Leishmania lifecycle progression: post-transcriptional control conducts the orchestra. Curr Opin Microbiol 2016; 34:82-89. [PMID: 27565628 DOI: 10.1016/j.mib.2016.08.004] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Revised: 08/09/2016] [Accepted: 08/10/2016] [Indexed: 12/30/2022]
Abstract
The successful progression of Leishmania spp. through their lifecycle entails a series of differentiation processes; the proliferative procyclic promastigote forms become quiescent, human-infective metacyclic promastigotes during metacyclogenesis in the sandfly vector, which then differentiate into amastigotes during amastigogenesis in the mammalian host. The progression to these infective forms requires two components: environmental cues and a coordinated cellular response. Recent studies have shown that the Leishmania cellular transformation into mammalian-infective stages is triggered by broad changes in the absolute and relative RNA and protein levels. In this review, we will discuss the implications of Leishmania transcriptomic and proteomic fluctuations, which adapt the parasitic cell for survival.
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Rao SJ, Meleppattu S, Pal JK. A GCN2-Like eIF2α Kinase (LdeK1) of Leishmania donovani and Its Possible Role in Stress Response. PLoS One 2016; 11:e0156032. [PMID: 27248816 PMCID: PMC4889150 DOI: 10.1371/journal.pone.0156032] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2015] [Accepted: 05/09/2016] [Indexed: 12/21/2022] Open
Abstract
Translation regulation in Leishmania parasites assumes significance particularly because they encounter myriad of stresses during their life cycle. The eukaryotic initiation factor 2α (eIF2α) kinases, the well-known regulators of translation initiation in higher eukaryotes have now been found to control various processes in these protozoan parasites as well. Here, we report on cloning and characterization of a GCN2-like eIF2α kinase from L. donovani and also on its modulation during nutrient starvation. We cloned a GCN2-like kinase from L. donovani, which we named as LdeK1 and validated it to be a functional eIF2α kinase by in vitro kinase assay. LdeK1 was found to be localized in the cytoplasm of the promastigotes with a five-fold higher expression in this stage of the parasite as compared to the axenic amastigotes. Phosphorylation of eIF2α and a G1-arrest was observed in response to nutrient starvation in the wild-type parasites. In contrast, phosphorylation was significantly impaired in a dominant-negative mutant of LdeK1 during this stress with a subsequent failure to bring about a G1-arrest during cell cycle. Thus, LdeK1 is a functional GCN2-like kinase of L. donovani which responds to nutrient starvation by phosphorylating its substrate, eIF2α and a G1-arrest in the cell cycle. Nutrient starvation is encountered by the parasites inside the vector which triggers metacyclogenesis. We therefore propose that global translational regulation by activation of LdeK1 followed by eIF2α phosphorylation and G1-arrest during nutrient starvation in the gut of sandfly vector could be one of the mechanisms to retool the cellular machinery required for metacyclogenesis of Leishmania promastigotes.
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Affiliation(s)
- Shilpa J. Rao
- Cell and Molecular Biology Laboratory, Department of Biotechnology, Savitribai Phule Pune University, Ganeshkhind, Pune-411007, India
- Interdisciplinary School of Health Sciences, Savitribai Phule Pune University, Ganeshkhind, Pune-411007, India
| | - Shimi Meleppattu
- Cell and Molecular Biology Laboratory, Department of Biotechnology, Savitribai Phule Pune University, Ganeshkhind, Pune-411007, India
| | - Jayanta K. Pal
- Cell and Molecular Biology Laboratory, Department of Biotechnology, Savitribai Phule Pune University, Ganeshkhind, Pune-411007, India
- * E-mail:
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Yao C, Wilson ME. Dynamics of sterol synthesis during development of Leishmania spp. parasites to their virulent form. Parasit Vectors 2016; 9:200. [PMID: 27071464 PMCID: PMC4830053 DOI: 10.1186/s13071-016-1470-0] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Accepted: 03/23/2016] [Indexed: 12/14/2022] Open
Abstract
Background The Leishmania spp. protozoa, the causative agents of the “neglected” tropical disease leishmaniasis, are transmitted to mammals by sand fly vectors. Within the sand fly, parasites transform from amastigotes to procyclic promastigotes, followed by development of virulent (metacyclic) promastigote forms. The latter are infectious to mammalian hosts. Biochemical components localized in the parasite plasma membrane such as proteins and sterols play a pivotal role in Leishmania pathogenesis. Leishmania spp. lack the enzymes for cholesterol synthesis, and the dynamics of sterol acquisition and biosynthesis in parasite developmental stages are not understood. We hypothesized that dynamic changes in sterol composition during metacyclogenesis contribute to the virulence of metacyclic promastigotes. Methods Sterols were extracted from logarithmic phase or metacyclic promastigotes grown in liquid culture with or without cholesterol, and analyzed qualitatively and quantitatively by gas chromatograph-mass spectrometry (GC-MS). TriTrypDB was searched for identification of genes involved in Leishmania sterol biosynthetic pathways. Results In total nine sterols were identified. There were dynamic changes in sterols during promastigote metacyclogenesis. Cholesterol in the culture medium affected sterol composition in different parasite stages. There were qualitative and relative quantitative differences between the sterol content of virulent versus avirulent parasite strains. A tentative sterol biosynthetic pathway in Leishmania spp. promastigotes was identified. Conclusions Significant differences in sterol composition were observed between promastigote stages, and between parasites exposed to different extracellular cholesterol in the environment. These data lay the foundation for further investigating the role of sterols in the pathogenesis of Leishmania spp. infections. Electronic supplementary material The online version of this article (doi:10.1186/s13071-016-1470-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Chaoqun Yao
- Department of Biomedical Sciences and One Health Center for Zoonoses and Tropical Veterinary Medicine, Ross University School of Veterinary Medicine, P.O. Box 334, Basseterre, St. Kitts, West Indies, ᅟ.
| | - Mary E Wilson
- Departments of Internal Medicine, Microbiology and Epidemiology, University of Iowa, Iowa City, IA, USA.,Iowa City VA Medical Center, Iowa City, IA, USA
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Hendrickx S, Leemans A, Mondelaers A, Rijal S, Khanal B, Dujardin JC, Delputte P, Cos P, Maes L. Comparative Fitness of a Parent Leishmania donovani Clinical Isolate and Its Experimentally Derived Paromomycin-Resistant Strain. PLoS One 2015; 10:e0140139. [PMID: 26469696 PMCID: PMC4607421 DOI: 10.1371/journal.pone.0140139] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2015] [Accepted: 09/22/2015] [Indexed: 11/19/2022] Open
Abstract
Paromomycin has recently been introduced for the treatment of visceral leishmaniasis and emergence of drug resistance can only be appropriately judged upon its long term routine use in the field. Understanding alterations in parasite behavior linked to paromomycin-resistance may be essential to assess the propensity for emergence and spread of resistant strains. A standardized and integrated laboratory approach was adopted to define and assess parasite fitness of both promastigotes and amastigotes using an experimentally induced paromomycin-resistant Leishmania donovani strain and its paromomycin-susceptible parent wild-type clinical isolate. Primary focus was placed on parasite growth and virulence, two major components of parasite fitness. The combination of in vitro and in vivo approaches enabled detailed comparison of wild-type and resistant strains for which no differences could be demonstrated with regard to promastigote growth, metacyclogenesis, in vitro infectivity, multiplication in primary peritoneal mouse macrophages and infectivity for Balb/c mice upon infection with 2 x 107 metacyclic promastigotes. Monitoring of in vitro intracellular amastigote multiplication revealed a consistent decrease in parasite burden over time for both wild-type and resistant parasites, an observation that was subsequently also confirmed in a larger set of L. donovani clinical isolates. Though the impact of these findings should be further explored, the study results suggest that the epidemiological implications of acquired paromomycin-resistance may remain minimal other than the loss of one of the last remaining drugs effective against visceral leishmaniasis.
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Affiliation(s)
- Sarah Hendrickx
- Laboratory for Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Antwerp, Belgium
| | - Annelies Leemans
- Laboratory for Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Antwerp, Belgium
| | - Annelies Mondelaers
- Laboratory for Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Antwerp, Belgium
| | - Suman Rijal
- BP Koirala Institute of Health Sciences, Dharan, Nepal
| | | | - Jean-Claude Dujardin
- Molecular Parasitology Unit, Institute of Tropical Medicine Antwerp, Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Peter Delputte
- Laboratory for Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Antwerp, Belgium
| | - Paul Cos
- Laboratory for Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Antwerp, Belgium
| | - Louis Maes
- Laboratory for Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Antwerp, Belgium
- * E-mail:
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Sacks DL, Melby PC. Animal models for the analysis of immune responses to leishmaniasis. ACTA ACUST UNITED AC 2015; 108:19.2.1-19.2.24. [PMID: 25640990 DOI: 10.1002/0471142735.im1902s108] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
This unit focuses on the murine model of cutaneous leishmaniasis and models of visceral leishmaniasis in mice and hamsters. Each basic protocol describes the methods used to inoculate parasites and to evaluate infections with regard to lesion progression and visceralization, and quantification of parasite load.
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Affiliation(s)
- David L Sacks
- National Institute of Allergy & Infectious Diseases, Bethesda, Maryland
| | - Peter C Melby
- University of Texas Medical Branch (UTMB), Galveston, Texas
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Yau WL, Pescher P, MacDonald A, Hem S, Zander D, Retzlaff S, Blisnick T, Rotureau B, Rosenqvist H, Wiese M, Bastin P, Clos J, Späth GF. The Leishmania donovani chaperone cyclophilin 40 is essential for intracellular infection independent of its stage-specific phosphorylation status. Mol Microbiol 2014; 93:80-97. [PMID: 24811325 DOI: 10.1111/mmi.12639] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/02/2014] [Indexed: 11/29/2022]
Abstract
During its life cycle, the protozoan pathogen Leishmania donovani is exposed to contrasting environments inside insect vector and vertebrate host, to which the parasite must adapt for extra- and intracellular survival. Combining null mutant analysis with phosphorylation site-specific mutagenesis and functional complementation we genetically tested the requirement of the L. donovani chaperone cyclophilin 40 (LdCyP40) for infection. Targeted replacement of LdCyP40 had no effect on parasite viability, axenic amastigote differentiation, and resistance to various forms of environmental stress in culture, suggesting important functional redundancy to other parasite chaperones. However, ultrastructural analyses and video microscopy of cyp40-/- promastigotes uncovered important defects in cell shape, organization of the subpellicular tubulin network and motility at stationary growth phase. More importantly, cyp40-/- parasites were unable to establish intracellular infection in murine macrophages and were eliminated during the first 24 h post infection. Surprisingly, cyp40-/- infectivity was restored in complemented parasites expressing a CyP40 mutant of the unique S274 phosphorylation site. Together our data reveal non-redundant CyP40 functions in parasite cytoskeletal remodelling relevant for the development of infectious parasites in vitro independent of its phosphorylation status, and provide a framework for the genetic analysis of Leishmania-specific phosphorylation sites and their role in regulating parasite protein function.
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Affiliation(s)
- Wai-Lok Yau
- Institut Pasteur and Centre National de la Recherche Scientifique URA 2581, Unité de Parasitologie Moléculaire et Signalisation, 25 rue du Dr Roux, F-75015, Paris, France; Clos Group (Leishmanasis), Bernhard-Nocht-Institut für Tropenmedizin, Bernhard-Nocht-Str. 74, D-20359, Hamburg, Germany
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Fernández-Moya SM, Carrington M, Estévez AM. A short RNA stem-loop is necessary and sufficient for repression of gene expression during early logarithmic phase in trypanosomes. Nucleic Acids Res 2014; 42:7201-9. [PMID: 24813448 PMCID: PMC4066783 DOI: 10.1093/nar/gku358] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
We have compared the transcriptomes of cultured procyclic Trypanosoma brucei cells in early and late logarithmic phases and found that ∼200 mRNAs were differentially regulated. In late log phase cells, the most upregulated mRNA encoded the nucleobase transporter NT8. The 3' untranslated region (UTR) of NT8 contains a short stem-loop cis-element that is necessary for the regulation of NT8 expression in response to external purine levels. When placed in the 3'-UTR of an unregulated transcript, the cis-element is sufficient to confer regulation in response to purines. To our knowledge, this is the first example of a discrete RNA element that can autonomously regulate gene expression in trypanosomes in response to an external factor and reveals an unprecedented purine-dependent signaling pathway that controls gene expression in eukaryotes.
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Affiliation(s)
- Sandra M Fernández-Moya
- Instituto de Parasitología y Biomedicina 'López-Neyra', IPBLN-CSIC, Parque Tecnológico de Ciencias de la Salud, Avda. del Conocimiento, s/n, 18016 Armilla, Granada, Spain
| | - Mark Carrington
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1QW, UK
| | - Antonio M Estévez
- Instituto de Parasitología y Biomedicina 'López-Neyra', IPBLN-CSIC, Parque Tecnológico de Ciencias de la Salud, Avda. del Conocimiento, s/n, 18016 Armilla, Granada, Spain
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34
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Metabolic reprogramming during purine stress in the protozoan pathogen Leishmania donovani. PLoS Pathog 2014; 10:e1003938. [PMID: 24586154 PMCID: PMC3937319 DOI: 10.1371/journal.ppat.1003938] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2013] [Accepted: 01/06/2014] [Indexed: 01/18/2023] Open
Abstract
The ability of Leishmania to survive in their insect or mammalian host is dependent upon an ability to sense and adapt to changes in the microenvironment. However, little is known about the molecular mechanisms underlying the parasite response to environmental changes, such as nutrient availability. To elucidate nutrient stress response pathways in Leishmania donovani, we have used purine starvation as the paradigm. The salvage of purines from the host milieu is obligatory for parasite replication; nevertheless, purine-starved parasites can persist in culture without supplementary purine for over three months, indicating that the response to purine starvation is robust and engenders parasite survival under conditions of extreme scarcity. To understand metabolic reprogramming during purine starvation we have employed global approaches. Whole proteome comparisons between purine-starved and purine-replete parasites over a 6–48 h span have revealed a temporal and coordinated response to purine starvation. Purine transporters and enzymes involved in acquisition at the cell surface are upregulated within a few hours of purine removal from the media, while other key purine salvage components are upregulated later in the time-course and more modestly. After 48 h, the proteome of purine-starved parasites is extensively remodeled and adaptations to purine stress appear tailored to deal with both purine deprivation and general stress. To probe the molecular mechanisms affecting proteome remodeling in response to purine starvation, comparative RNA-seq analyses, qRT-PCR, and luciferase reporter assays were performed on purine-starved versus purine-replete parasites. While the regulation of a minority of proteins tracked with changes at the mRNA level, for many regulated proteins it appears that proteome remodeling during purine stress occurs primarily via translational and/or post-translational mechanisms. Leishmania, the cause of a deadly spectrum of diseases in humans, surmounts a number of environmental challenges, including changes in the availability of salvageable nutrients, to successfully colonize its host. Adaptation to environmental stress is clearly of significance in parasite biology, but the underlying mechanisms are not well understood. To simulate the response to periodic nutrient scarcity in vivo, we have induced purine starvation in vitro. Purines are essential for growth and viability, and serve as the major energy currency of cells. Leishmania cannot synthesize purines and must salvage them from the surroundings. Extracellular purine depletion in culture induces a robust survival response in Leishmania, whereby growth arrests, but parasites persist for months. To profile the events that enable endurance of purine starvation, we used shotgun proteomics. Our data suggest that purine starvation induces extensive proteome remodeling, tailored to enhance purine capture and recycling, reduce energy expenditures, and maintain viability of the metabolically active, non-dividing population. Through global and targeted approaches, we reveal that proteome remodeling is multifaceted, and occurs through an array of responses at the mRNA, translational, and post-translational level. Our data provide one of the most inclusive views of adaptation to microenvironmental stress in Leishmania.
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35
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Sacks DL, Melby PC. Animal models for the analysis of immune responses to leishmaniasis. CURRENT PROTOCOLS IN IMMUNOLOGY 2008; Chapter 19:Unit 19.2. [PMID: 18432753 DOI: 10.1002/0471142735.im1902s28] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
This unit focuses on the murine model of cutaneous leishmaniasis and models of visceral leishmaniasis in mice and hamsters. Each basic protocol describes the methods used to inoculate parasites and to evaluate infections with regard to lesion progression and visceralization, and quantification of parasite load. Five support protocols are provided; two for the growth and isolation of metacyclic promastigotes from in vitro culture, one for isolation of tissue amastigotes from infected animals, one for cryopreservation of parasites, and one for the preparation of blood agar plates for quantitation of parasite numbers in infected tissue.
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Affiliation(s)
- D L Sacks
- National Institute of Allergy & Infectious, Diseases, Bethesda, Maryland, USA
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