1
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Munjal A, Rex DAB, Garg P, Prasad TSK, Mishra SK, Malhotra Y, Yadav D, John J, P P, Rawal K, Singh S. Mass Spectrometric and Artificial Intelligence-Based Identification of the Secretome of Plasmodium falciparum Merozoites to Provide Novel Candidates for Vaccine Development Pipeline. Proteomics Clin Appl 2024; 18:e202300115. [PMID: 39082488 DOI: 10.1002/prca.202300115] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 05/24/2024] [Accepted: 07/16/2024] [Indexed: 11/15/2024]
Abstract
PURPOSE Merozoites are the only extracellular form of blood stage parasites, making it a worthwhile target. Multiple invasins that are stored in the merozoite apical organelles, are secreted just prior to invasion, and mediates its interaction with RBC. A comprehensive identification of all these secreted invasins is lacking and this study addresses that gap. EXPERIMENTAL DESIGN Pf3D7 merozoites were enriched and triggered to discharge apical organelle contents by exposure to ionic conditions mimicking that of blood plasma. The secreted proteins were separated from cellular contents and both the fractions were subjected to proteomic analysis. Also, the identified secreted proteins were subjected to GO, PPI network analysis, and AI-based in silico approach to understand their vaccine candidacy. RESULTS A total of 63 proteins were identified in the secretory fraction with membrane and apical organellar localization. This includes various MSPs, micronemal EBAs and rhoptry bulb proteins, which play a crucial role in initial and late merozoite attachment, and majority of them qualified as vaccine candidates. CONCLUSION AND CLINICAL RELEVANCE We, for the first time, report the secretory repertoire of merozoite and its status for vaccine candidacy. This information can be utilized to develop better invasion blocking multisubunit vaccines, comprising of immunological epitopes from several secreted invasins.
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Affiliation(s)
- Akshay Munjal
- Special Centre of Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
| | - Devasahayam Arokia Balaya Rex
- Center for Systems Biology and Molecular Medicine, Yenepoya Research Centre, Yenepoya (Deemed to be University), Mangalore, India
- Department of Laboratory Medicine and Pathology, Rochester, Minnesota, USA
| | - Prachi Garg
- Special Centre of Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
| | | | - Sai Kumar Mishra
- Center for Computational Biology and Bioinformatics, Amity Institute of Biotechnology, Noida, Uttar Pradesh, India
| | - Yuktika Malhotra
- Center for Computational Biology and Bioinformatics, Amity Institute of Biotechnology, Noida, Uttar Pradesh, India
| | - Deepika Yadav
- Center for Computational Biology and Bioinformatics, Amity Institute of Biotechnology, Noida, Uttar Pradesh, India
| | - Jerry John
- Center for Computational Biology and Bioinformatics, Amity Institute of Biotechnology, Noida, Uttar Pradesh, India
| | - Preeti P
- Center for Computational Biology and Bioinformatics, Amity Institute of Biotechnology, Noida, Uttar Pradesh, India
| | - Kamal Rawal
- Center for Computational Biology and Bioinformatics, Amity Institute of Biotechnology, Noida, Uttar Pradesh, India
| | - Shailja Singh
- Special Centre of Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
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2
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Charneau S, de Oliveira LS, Zenonos Z, Hopp CS, Bastos IMD, Loew D, Lombard B, Pandolfo Silveira A, de Carvalho Nardeli Basílio Lobo G, Bao SN, Grellier P, Rayner JC. APEX2-based proximity proteomic analysis identifies candidate interactors for Plasmodium falciparum knob-associated histidine-rich protein in infected erythrocytes. Sci Rep 2024; 14:11242. [PMID: 38755230 PMCID: PMC11099048 DOI: 10.1038/s41598-024-61295-w] [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: 12/19/2023] [Accepted: 05/03/2024] [Indexed: 05/18/2024] Open
Abstract
The interaction of Plasmodium falciparum-infected red blood cells (iRBCs) with the vascular endothelium plays a crucial role in malaria pathology and disease. KAHRP is an exported P. falciparum protein involved in iRBC remodelling, which is essential for the formation of protrusions or "knobs" on the iRBC surface. These knobs and the proteins that are concentrated within them allow the parasites to escape the immune response and host spleen clearance by mediating cytoadherence of the iRBC to the endothelial wall, but this also slows down blood circulation, leading in some cases to severe cerebral and placental complications. In this work, we have applied genetic and biochemical tools to identify proteins that interact with P. falciparum KAHRP using enhanced ascorbate peroxidase 2 (APEX2) proximity-dependent biotinylation and label-free shotgun proteomics. A total of 30 potential KAHRP-interacting candidates were identified, based on the assigned fragmented biotinylated ions. Several identified proteins have been previously reported to be part of the Maurer's clefts and knobs, where KAHRP resides. This study may contribute to a broader understanding of P. falciparum protein trafficking and knob architecture and shows for the first time the feasibility of using APEX2-proximity labelling in iRBCs.
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Affiliation(s)
- Sébastien Charneau
- Laboratory of Biochemistry and Protein Chemistry, Department of Cell Biology, Institute of Biology, University of Brasília, Brasília, 70910-900, Brazil.
| | - Lucas Silva de Oliveira
- Laboratory of Biochemistry and Protein Chemistry, Department of Cell Biology, Institute of Biology, University of Brasília, Brasília, 70910-900, Brazil
- UMR 7245 MCAM Molecules of Communication and Adaptation of Microorganisms, Muséum National d'Histoire Naturelle, CNRS, 75231, Paris Cedex 05, France
| | - Zenon Zenonos
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridgeshire, CB10 1SA, UK
- Biologics Engineering, Oncology R&D, AstraZenecaGranta Park, Cambridge, UK
| | - Christine S Hopp
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridgeshire, CB10 1SA, UK
- Protozoa Immunology, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - Izabela M D Bastos
- Laboratory of Host Pathogen Interaction, Department of Cell Biology, Institute of Biology, University of Brasília, Brasília, 70910-900, Brazil
| | - Damarys Loew
- Institut Curie, Centre de Recherche, PSL Research University, CurieCoreTech Mass Spectrometry Proteomics, 26 rue d'Ulm, 75248, Paris Cedex 05, France
| | - Bérangère Lombard
- Institut Curie, Centre de Recherche, PSL Research University, CurieCoreTech Mass Spectrometry Proteomics, 26 rue d'Ulm, 75248, Paris Cedex 05, France
| | - Ariane Pandolfo Silveira
- Laboratory of Microscopy and Microanalysis, Department of Cell Biology, Institute of Biology, University of Brasilia, Brasília, 70910-900, Brazil
| | | | - Sônia Nair Bao
- Laboratory of Microscopy and Microanalysis, Department of Cell Biology, Institute of Biology, University of Brasilia, Brasília, 70910-900, Brazil
| | - Philippe Grellier
- UMR 7245 MCAM Molecules of Communication and Adaptation of Microorganisms, Muséum National d'Histoire Naturelle, CNRS, 75231, Paris Cedex 05, France
| | - Julian C Rayner
- Cambridge Institute for Medical Research, University of Cambridge, Hills Road, Cambridge, CB2 0XY, UK
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3
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Ahmad T, Alhammadi BA, Almaazmi SY, Arafa S, Blatch GL, Dutta T, Gestwicki JE, Keyzers RA, Shonhai A, Singh H. Plasmodium falciparum heat shock proteins as antimalarial drug targets: An update. Cell Stress Chaperones 2024; 29:326-337. [PMID: 38518861 PMCID: PMC10990865 DOI: 10.1016/j.cstres.2024.03.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Revised: 02/25/2024] [Accepted: 03/18/2024] [Indexed: 03/24/2024] Open
Abstract
Global efforts to eradicate malaria are threatened by multiple factors, particularly the emergence of antimalarial drug resistant strains of Plasmodium falciparum. Heat shock proteins (HSPs), particularly P. falciparum HSPs (PfHSPs), represent promising drug targets due to their essential roles in parasite survival and virulence across the various life cycle stages. Despite structural similarities between human and malarial HSPs posing challenges, there is substantial evidence for subtle differences that could be exploited for selective drug targeting. This review provides an update on the potential of targeting various PfHSP families (particularly PfHSP40, PfHSP70, and PfHSP90) and their interactions within PfHSP complexes as a strategy to develop new antimalarial drugs. In addition, the need for a deeper understanding of the role of HSP complexes at the host-parasite interface is highlighted, especially heterologous partnerships between human and malarial HSPs, as this opens novel opportunities for targeting protein-protein interactions crucial for malaria parasite survival and pathogenesis.
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Affiliation(s)
- Tanveer Ahmad
- Faculty of Health Sciences, Higher Colleges of Technology, Sharjah, United Arab Emirates
| | - Bushra A Alhammadi
- Faculty of Health Sciences, Higher Colleges of Technology, Sharjah, United Arab Emirates
| | - Shaikha Y Almaazmi
- Faculty of Health Sciences, Higher Colleges of Technology, Sharjah, United Arab Emirates
| | - Sahar Arafa
- Faculty of Health Sciences, Higher Colleges of Technology, Sharjah, United Arab Emirates
| | - Gregory L Blatch
- Faculty of Health Sciences, Higher Colleges of Technology, Sharjah, United Arab Emirates; Biomedical Biotechnology Research Unit, Department of Biochemistry and Microbiology, Rhodes University, Grahamstown, South Africa.
| | - Tanima Dutta
- Department of Diagnostic Genomics, Pathwest, QEII Medical Centre, Nedlands, Western Australia, Australia
| | - Jason E Gestwicki
- Department of Pharmaceutical Chemistry and the Institute for Neurodegenerative Diseases, University of California San Francisco, San Francisco, CA, USA
| | - Robert A Keyzers
- Centre for Biodiscovery & School of Chemical and Physical Sciences, Victoria University of Wellington, Wellington, New Zealand
| | - Addmore Shonhai
- Department of Biochemistry and Microbiology, University of Venda, Thohoyandou, South Africa
| | - Harpreet Singh
- Department of Bioinformatics, Hans Raj Mahila Maha Vidyalaya, Jalandhar, Punjab, India
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4
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Kaur J, Mishra PC, Hora R. Molecular Players at the Sorting Stations of Malaria Parasite 'Plasmodium falciparum'. Curr Protein Pept Sci 2024; 25:427-437. [PMID: 38409726 DOI: 10.2174/0113892037282522240130090156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Revised: 01/12/2024] [Accepted: 01/18/2024] [Indexed: 02/28/2024]
Abstract
The apicomplexan pathogenic parasite 'Plasmodium falciparum' (Pf) is responsible for most of the malaria related mortality. It resides in and refurbishes the infected red blood cells (iRBCs) for its own survival and to suffice its metabolic needs. Remodeling of host erythrocytes involves alteration of physical and biochemical properties of the membrane and genesis of new parasite induced structures within the iRBCs. The generated structures include knobs and solute ion channels on the erythrocyte surface and specialized organelles i.e. Maurer's clefts (MCs) in the iRBC cytosol. The above processes are mediated by exporting a large repertoire of proteins to the host cell, most of which are transported via MCs, the sorting stations in parasitized erythrocytes. Information about MC biogenesis and the molecules involved in maintaining MC architecture remains incompletely elucidated. Here, we have compiled a list of experimentally known MC resident proteins, several of which have roles in maintaining its architecture and function. Our short review covers available data on the domain organization, orthologues, topology and specific roles of these proteins. We highlight the current knowledge gaps in our understanding of MCs as crucial organelles involved in parasite biology and disease pathogenesis.
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Affiliation(s)
- Jasweer Kaur
- Department of Biochemistry, Govt. College for Girls, Ludhiana, Punjab, India (Affiliated to Panjab University, Chandigarh), India
| | | | - Rachna Hora
- Department of Molecular Biology and Biochemistry, Guru Nanak Dev University Amritsar, Punjab, India
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5
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Siau A, Ang JW, Sheriff O, Hoo R, Loh HP, Tay D, Huang X, Yam XY, Lai SK, Meng W, Julca I, Kwan SS, Mutwil M, Preiser PR. Comparative spatial proteomics of Plasmodium-infected erythrocytes. Cell Rep 2023; 42:113419. [PMID: 37952150 DOI: 10.1016/j.celrep.2023.113419] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 07/14/2023] [Accepted: 10/25/2023] [Indexed: 11/14/2023] Open
Abstract
Plasmodium parasites contribute to one of the highest global infectious disease burdens. To achieve this success, the parasite has evolved a range of specialized subcellular compartments to extensively remodel the host cell for its survival. The information to fully understand these compartments is likely hidden in the so far poorly characterized Plasmodium species spatial proteome. To address this question, we determined the steady-state subcellular location of more than 12,000 parasite proteins across five different species by extensive subcellular fractionation of erythrocytes infected by Plasmodium falciparum, Plasmodium knowlesi, Plasmodium yoelii, Plasmodium berghei, and Plasmodium chabaudi. This comparison of the pan-species spatial proteomes and their expression patterns indicates increasing species-specific proteins associated with the more external compartments, supporting host adaptations and post-transcriptional regulation. The spatial proteome offers comprehensive insight into the different human, simian, and rodent Plasmodium species, establishing a powerful resource for understanding species-specific host adaptation processes in the parasite.
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Affiliation(s)
- Anthony Siau
- Nanyang Technological University, School of Biological Sciences, Singapore 637551, Singapore
| | - Jing Wen Ang
- Nanyang Technological University, School of Biological Sciences, Singapore 637551, Singapore
| | - Omar Sheriff
- Nanyang Technological University, School of Biological Sciences, Singapore 637551, Singapore
| | - Regina Hoo
- Nanyang Technological University, School of Biological Sciences, Singapore 637551, Singapore
| | - Han Ping Loh
- Nanyang Technological University, School of Biological Sciences, Singapore 637551, Singapore
| | - Donald Tay
- Nanyang Technological University, School of Biological Sciences, Singapore 637551, Singapore
| | - Ximei Huang
- Nanyang Technological University, School of Biological Sciences, Singapore 637551, Singapore
| | - Xue Yan Yam
- Nanyang Technological University, School of Biological Sciences, Singapore 637551, Singapore
| | - Soak Kuan Lai
- Nanyang Technological University, School of Biological Sciences, Singapore 637551, Singapore
| | - Wei Meng
- Nanyang Technological University, School of Biological Sciences, Singapore 637551, Singapore
| | - Irene Julca
- Nanyang Technological University, School of Biological Sciences, Singapore 637551, Singapore
| | - Sze Siu Kwan
- Nanyang Technological University, School of Biological Sciences, Singapore 637551, Singapore
| | - Marek Mutwil
- Nanyang Technological University, School of Biological Sciences, Singapore 637551, Singapore
| | - Peter R Preiser
- Nanyang Technological University, School of Biological Sciences, Singapore 637551, Singapore.
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6
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Anaguano D, Dedkhad W, Brooks CF, Cobb DW, Muralidharan V. Time-resolved proximity biotinylation implicates a porin protein in export of transmembrane malaria parasite effectors. J Cell Sci 2023; 136:jcs260506. [PMID: 37772444 PMCID: PMC10651097 DOI: 10.1242/jcs.260506] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Accepted: 09/21/2023] [Indexed: 09/30/2023] Open
Abstract
The malaria-causing parasite, Plasmodium falciparum completely remodels its host red blood cell (RBC) through the export of several hundred parasite proteins, including transmembrane proteins, across multiple membranes to the RBC. However, the process by which these exported membrane proteins are extracted from the parasite plasma membrane for export remains unknown. To address this question, we fused the exported membrane protein, skeleton binding protein 1 (SBP1), with TurboID, a rapid, efficient and promiscuous biotin ligase (SBP1TbID). Using time-resolved proximity biotinylation and label-free quantitative proteomics, we identified two groups of SBP1TbID interactors - early interactors (pre-export) and late interactors (post-export). Notably, two promising membrane-associated proteins were identified as pre-export interactors, one of which possesses a predicted translocon domain, that could facilitate the export of membrane proteins. Further investigation using conditional mutants of these candidate proteins showed that these proteins were essential for asexual growth and localize to the host-parasite interface during early stages of the intraerythrocytic cycle. These data suggest that they might play a role in ushering membrane proteins from the parasite plasma membrane for export to the host RBC.
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Affiliation(s)
- David Anaguano
- Department of Cellular Biology, University of Georgia, Athens, GA, USA
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA
| | - Watcharatip Dedkhad
- Department of Cellular Biology, University of Georgia, Athens, GA, USA
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA
| | - Carrie F. Brooks
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA
| | - David W. Cobb
- Department of Cellular Biology, University of Georgia, Athens, GA, USA
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA
| | - Vasant Muralidharan
- Department of Cellular Biology, University of Georgia, Athens, GA, USA
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA
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7
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Bekić V, Kilian N. Novel secretory organelles of parasite origin - at the center of host-parasite interaction. Bioessays 2023; 45:e2200241. [PMID: 37518819 DOI: 10.1002/bies.202200241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2022] [Revised: 06/26/2023] [Accepted: 06/28/2023] [Indexed: 08/01/2023]
Abstract
Reorganization of cell organelle-deprived host red blood cells by the apicomplexan malaria parasite Plasmodium falciparum enables their cytoadherence to endothelial cells that line the microvasculature. This increases the time red blood cells infected with mature developmental stages remain within selected organs such as the brain to avoid the spleen passage, which can lead to severe complications and cumulate in patient death. The Maurer's clefts are a novel secretory organelle of parasite origin established by the parasite in the cytoplasm of the host red blood cell in order to facilitate the establishment of cytoadherence by conducting the trafficking of immunovariant adhesins to the host cell surface. Another important function of the organelle is the sorting of other proteins the parasite traffics into its host cell. Although the organelle is of high importance for the pathology of malaria, additional putative functions, structure, and genesis remain shrouded in mystery more than a century after its discovery. In this review, we highlight our current knowledge about the Maurer's clefts and other novel secretory organelles established within the host cell cytoplasm by human-pathogenic malaria parasites and other parasites that reside within human red blood cells.
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Affiliation(s)
- Viktor Bekić
- School of Medicine, University of Zagreb, Zagreb, Croatia
| | - Nicole Kilian
- Centre for Infectious Diseases, Parasitology, Heidelberg University Hospital, Heidelberg, Germany
- Department of Medical Biochemistry, Faculty of Basic Medical Sciences, Delta State University, Abraka, Nigeria
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8
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Erath J, Djuranovic S. Association of the receptor for activated C-kinase 1 with ribosomes in Plasmodium falciparum. J Biol Chem 2022; 298:101954. [PMID: 35452681 PMCID: PMC9120242 DOI: 10.1016/j.jbc.2022.101954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 03/31/2022] [Accepted: 04/13/2022] [Indexed: 11/18/2022] Open
Abstract
The receptor for activated C-kinase 1 (RACK1), a highly conserved eukaryotic protein, is known to have many varying biological roles and functions. Previous work has established RACK1 as a ribosomal protein, with defined regions important for ribosome binding in eukaryotic cells. In Plasmodium falciparum, RACK1 has been shown to be required for parasite growth, however, conflicting evidence has been presented about RACK1 ribosome binding and its role in mRNA translation. Given the importance of RACK1 as a regulatory component of mRNA translation and ribosome quality control, the case could be made in parasites that RACK1 either binds or does not bind the ribosome. Here, we used bioinformatics and transcription analyses to further characterize the P. falciparum RACK1 protein. Based on homology modeling and structural analyses, we generated a model of P. falciparum RACK1. We then explored mutant and chimeric human and P. falciparum RACK1 protein binding properties to the human and P. falciparum ribosome. We found that WT, chimeric, and mutant RACK1 exhibit distinct ribosome interactions suggesting different binding characteristics for P. falciparum and human RACK1 proteins. The ribosomal binding of RACK1 variants in human and parasite cells shown here demonstrates that although RACK1 proteins have highly conserved sequences and structures across species, ribosomal binding is affected by species-specific alterations to this protein. In conclusion, we show that in the case of P. falciparum, contrary to the structural data, RACK1 is found to bind ribosomes and actively translating polysomes in parasite cells.
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Affiliation(s)
- Jessey Erath
- Department of Cell Biology and Physiology, Washington University School of Medicine, St Louis, Missouri, USA
| | - Sergej Djuranovic
- Department of Cell Biology and Physiology, Washington University School of Medicine, St Louis, Missouri, USA.
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9
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Silvestre A, Shintre SS, Rachidi N. Released Parasite-Derived Kinases as Novel Targets for Antiparasitic Therapies. Front Cell Infect Microbiol 2022; 12:825458. [PMID: 35252034 PMCID: PMC8893276 DOI: 10.3389/fcimb.2022.825458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 01/25/2022] [Indexed: 11/13/2022] Open
Abstract
The efficient manipulation of their host cell is an essential feature of intracellular parasites. Most molecular mechanisms governing the subversion of host cell by protozoan parasites involve the release of parasite-derived molecules into the host cell cytoplasm and direct interaction with host proteins. Among these released proteins, kinases are particularly important as they govern the subversion of important host pathways, such as signalling or metabolic pathways. These enzymes, which catalyse the transfer of a phosphate group from ATP onto serine, threonine, tyrosine or histidine residues to covalently modify proteins, are involved in numerous essential biological processes such as cell cycle or transport. Although little is known about the role of most of the released parasite-derived kinases in the host cell, they are examples of kinases hijacking host cellular pathways such as signal transduction or apoptosis, which are essential for immune response evasion as well as parasite survival and development. Here we present the current knowledge on released protozoan kinases and their involvement in host-pathogen interactions. We also highlight the knowledge gaps remaining before considering those kinases - involved in host signalling subversion - as antiparasitic drug targets.
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Affiliation(s)
- Anne Silvestre
- INRAE, Université de Tours, ISP, Nouzilly, France
- *Correspondence: Anne Silvestre, ; Najma Rachidi,
| | - Sharvani Shrinivas Shintre
- INRAE, Université de Tours, ISP, Nouzilly, France
- Institut Pasteur, Université de Paris and INSERM U1201, Unité de Parasitologie Moléculaire et Signalisation, Paris, France
| | - Najma Rachidi
- Institut Pasteur, Université de Paris and INSERM U1201, Unité de Parasitologie Moléculaire et Signalisation, Paris, France
- *Correspondence: Anne Silvestre, ; Najma Rachidi,
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10
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Keitany GJ, Jenkins BJ, Obiakor HT, Daniel S, Muehlenbachs A, Semblat JP, Gamain B, Doritchamou JYA, Desai SA, MacDonald NJ, Narum DL, Morrison R, Saveria T, Vignali M, Oleinikov AV, Fried M, Duffy PE. An invariant protein that co-localizes with VAR2CSA on Plasmodium falciparum-infected red cells binds to chondroitin sulfate A. J Infect Dis 2021; 225:2011-2022. [PMID: 34718641 DOI: 10.1093/infdis/jiab550] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 10/25/2021] [Indexed: 11/14/2022] Open
Abstract
Plasmodium falciparum-infected red blood cells (iRBCs) bind and sequester in deep vascular beds, causing malaria-related disease and death. In pregnant women, VAR2CSA binds to chondroitin sulfate A (CSA) and mediates placental sequestration, making it the major placental malaria (PM) vaccine target. Here, we characterize an invariant protein associated with PM called Plasmodium falciparum chondroitin sulfate A ligand (PfCSA-L). Recombinant PfCSA-L binds both placental CSA and VAR2CSA with nanomolar affinity, and is coexpressed on the iRBC surface with VAR2CSA. Unlike VAR2CSA, which is anchored by a transmembrane domain, PfCSA-L is peripherally associated with the outer surface of knobs through high affinity protein-protein interactions with VAR2CSA. This suggests iRBC sequestration involves complexes of invariant and variant surface proteins, allowing parasites to maintain both diversity and function at the iRBC surface. PfCSA-L is a promising target for intervention because it is well conserved, exposed on infected cells, and expressed and localized with VAR2CSA.
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Affiliation(s)
- Gladys J Keitany
- Center for Infectious Disease Research, Seattle, WA, USA.,University of Washington, Department of Pathobiology, Seattle, WA, USA
| | - Bethany J Jenkins
- Laboratory of Malaria Immunology and Vaccinology, NIAID, NIH, Bethesda, MD, USA
| | - Harold T Obiakor
- Laboratory of Malaria Immunology and Vaccinology, NIAID, NIH, Bethesda, MD, USA
| | - Shaji Daniel
- Laboratory of Malaria Immunology and Vaccinology, NIAID, NIH, Bethesda, MD, USA
| | - Atis Muehlenbachs
- University of Washington Medical Center, Anatomic Pathology, Seattle, WA, USA
| | - Jean-Philippe Semblat
- Université de Paris, Biologie Intégrée du Globule Rouge, UMR_S1134, Inserm, F-75015, Paris, France
| | - Benoit Gamain
- Université de Paris, Biologie Intégrée du Globule Rouge, UMR_S1134, Inserm, F-75015, Paris, France
| | | | - Sanjay A Desai
- Laboratory of Malaria and Vector Research, NIAID, NIH, Rockville, MD
| | | | - David L Narum
- Laboratory of Malaria Immunology and Vaccinology, NIAID, NIH, Bethesda, MD, USA
| | | | - Tracy Saveria
- Center for Infectious Disease Research, Seattle, WA, USA
| | | | | | - Michal Fried
- Center for Infectious Disease Research, Seattle, WA, USA.,University of Washington, Department of Pathobiology, Seattle, WA, USA.,Laboratory of Malaria Immunology and Vaccinology, NIAID, NIH, Bethesda, MD, USA
| | - Patrick E Duffy
- Center for Infectious Disease Research, Seattle, WA, USA.,University of Washington, Department of Pathobiology, Seattle, WA, USA.,Laboratory of Malaria Immunology and Vaccinology, NIAID, NIH, Bethesda, MD, USA
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11
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Expression Patterns of Plasmodium falciparum Clonally Variant Genes at the Onset of a Blood Infection in Malaria-Naive Humans. mBio 2021; 12:e0163621. [PMID: 34340541 PMCID: PMC8406225 DOI: 10.1128/mbio.01636-21] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Clonally variant genes (CVGs) play fundamental roles in the adaptation of Plasmodium falciparum to fluctuating conditions of the human host. However, their expression patterns under the natural conditions of the blood circulation have been characterized in detail for only a few specific gene families. Here, we provide a detailed characterization of the complete P. falciparum transcriptome across the full intraerythrocytic development cycle (IDC) at the onset of a blood infection in malaria-naive human volunteers. We found that the vast majority of transcriptional differences between parasites obtained from the volunteers and the parental parasite line maintained in culture occurred in CVGs. In particular, we observed a major increase in the transcript levels of most genes of the pfmc-2tm and gbp families and of specific genes of other families, such as phist, hyp10, rif, or stevor, in addition to previously reported changes in var and clag3 gene expression. Increased transcript levels of individual pfmc-2tm, rif, and stevor genes involved activation in small subsets of parasites. Large transcriptional differences correlated with changes in the distribution of heterochromatin, confirming their epigenetic nature. Furthermore, the similar expression of several CVGs between parasites collected at different time points along the blood infection suggests that the epigenetic memory for multiple CVG families is lost during transmission stages, resulting in a reset of their transcriptional state. Finally, the CVG expression patterns observed in a volunteer likely infected by a single sporozoite suggest that new epigenetic patterns are established during liver stages.
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12
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Jonsdottir TK, Counihan NA, Modak JK, Kouskousis B, Sanders PR, Gabriela M, Bullen HE, Crabb BS, de Koning-Ward TF, Gilson PR. Characterisation of complexes formed by parasite proteins exported into the host cell compartment of Plasmodium falciparum infected red blood cells. Cell Microbiol 2021; 23:e13332. [PMID: 33774908 PMCID: PMC8365696 DOI: 10.1111/cmi.13332] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 03/17/2021] [Accepted: 03/23/2021] [Indexed: 12/11/2022]
Abstract
During its intraerythrocytic life cycle, the human malaria parasite Plasmodium falciparum supplements its nutritional requirements by scavenging substrates from the plasma through the new permeability pathways (NPPs) installed in the red blood cell (RBC) membrane. Parasite proteins of the RhopH complex: CLAG3, RhopH2, RhopH3, have been implicated in NPP activity. Here, we studied 13 exported proteins previously hypothesised to interact with RhopH2, to study their potential contribution to the function of NPPs. NPP activity assays revealed that the 13 proteins do not appear to be individually important for NPP function, as conditional knockdown of these proteins had no effect on sorbitol uptake. Intriguingly, reciprocal immunoprecipitation assays showed that five of the 13 proteins interact with all members of the RhopH complex, with PF3D7_1401200 showing the strongest association. Mass spectrometry‐based proteomics further identified new protein complexes; a cytoskeletal complex and a Maurer's clefts/J‐dot complex, which overall helps clarify protein–protein interactions within the infected RBC (iRBC) and is suggestive of the potential trafficking route of the RhopH complex itself to the RBC membrane.
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Affiliation(s)
- Thorey K Jonsdottir
- Burnet Institute, Melbourne, Australia.,Department of Microbiology and Immunology, University of Melbourne, Melbourne, Australia
| | | | - Joyanta K Modak
- School of Medicine, Deakin University, Waurn Ponds, Australia
| | - Betty Kouskousis
- Burnet Institute, Melbourne, Australia.,Monash Micro-imaging, Monash University, Melbourne, Australia
| | | | - Mikha Gabriela
- Burnet Institute, Melbourne, Australia.,School of Medicine, Deakin University, Waurn Ponds, Australia
| | | | - Brendan S Crabb
- Burnet Institute, Melbourne, Australia.,Department of Microbiology and Immunology, University of Melbourne, Melbourne, Australia.,Department of Microbiology, Monash University, Melbourne, Australia
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13
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Yadavalli R, Peterson JW, Drazba JA, Sam-Yellowe TY. Trafficking and Association of Plasmodium falciparum MC-2TM with the Maurer's Clefts. Pathogens 2021; 10:pathogens10040431. [PMID: 33916455 PMCID: PMC8066109 DOI: 10.3390/pathogens10040431] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Revised: 03/28/2021] [Accepted: 03/30/2021] [Indexed: 12/05/2022] Open
Abstract
In this study, we investigated stage specific expression, trafficking, solubility and topology of endogenous PfMC-2TM in P. falciparum (3D7) infected erythrocytes. Following Brefeldin A (BFA) treatment of parasites, PfMC-2TM traffic was evaluated using immunofluorescence with antibodies reactive with PfMC-2TM. PfMC-2TM is sensitive to BFA treatment and permeabilization of infected erythrocytes with streptolysin O (SLO) and saponin, showed that the N and C-termini of PfMC-2TM are exposed to the erythrocyte cytoplasm with the central portion of the protein protected in the MC membranes. PfMC-2TM was expressed as early as 4 h post invasion (hpi), was tightly colocalized with REX-1 and trafficked to the erythrocyte membrane without a change in solubility. PfMC-2TM associated with the MC and infected erythrocyte membrane and was resistant to extraction with alkaline sodium carbonate, suggestive of protein-lipid interactions with membranes of the MC and erythrocyte. PfMC-2TM is an additional marker of the nascent MCs.
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Affiliation(s)
- Raghavendra Yadavalli
- Department of Biological, Geological, and Environmental Sciences, Cleveland State University, Cleveland, OH 44115, USA;
| | - John W. Peterson
- Imaging Core Facility, The Cleveland Clinic, Cleveland, OH 44195, USA; (J.W.P.); (J.A.D.)
| | - Judith A. Drazba
- Imaging Core Facility, The Cleveland Clinic, Cleveland, OH 44195, USA; (J.W.P.); (J.A.D.)
| | - Tobili Y. Sam-Yellowe
- Department of Biological, Geological, and Environmental Sciences, Cleveland State University, Cleveland, OH 44115, USA;
- Correspondence: ; Tel.: +1-216-687-2068
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14
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Identification of Plasmodium falciparum-specific protein PIESP2 as a novel virulence factor related to cerebral malaria. Int J Biol Macromol 2021; 177:535-547. [PMID: 33631268 DOI: 10.1016/j.ijbiomac.2021.02.145] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Revised: 01/21/2021] [Accepted: 02/19/2021] [Indexed: 01/23/2023]
Abstract
Cerebral malaria (CM) is the most severe complication caused by Plasmodium falciparum infection. The pathophysiological changes caused by parasite virulence factors and the human immune response to parasites contribute to CM. To date, very few parasite virulence proteins have been found to participate in CM. Here, we employed comparative genomics analysis and identified parasite-infected erythrocyte specific protein 2 (PIESP2) to be a CM-related protein. We conducted further experimental investigations and found that PIESP2 is an immunogenic protein. PIESP2 expression begins at the early trophozoite stage and progressively increases with parasite development. Although PIESP2 proteins mainly reside within infected red blood cells (IRBCs), some of them are present on the IRBC surface at the pigmented stage. Moreover, blockage of PIESP2 by antiserum apparently inhibited the adhesion of IRBCs to brain microvascular endothelial cells (BMECs). Western blot analysis detected the binding of PIESP2 to BMECs. Transcriptional analysis revealed that the binding of PIESP2 to BMECs can increase the expression of genes involved in the inflammatory response but decrease the expression of genes related to the anchoring junction. Overall, PIESP2 might be associated with CM by mediating the sequestration of IRBCs, inducing the inflammation response, and impairing the integrity of blood-brain barrier.
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15
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Florentin A, Cobb DW, Kudyba HM, Muralidharan V. Directing traffic: Chaperone-mediated protein transport in malaria parasites. Cell Microbiol 2020; 22:e13215. [PMID: 32388921 PMCID: PMC7282954 DOI: 10.1111/cmi.13215] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 04/12/2020] [Accepted: 04/14/2020] [Indexed: 12/16/2022]
Abstract
The ability of eukaryotic parasites from the phylum Apicomplexa to cause devastating diseases is predicated upon their ability to maintain faithful and precise protein trafficking mechanisms. Their parasitic life cycle depends on the trafficking of effector proteins to the infected host cell, transport of proteins to several critical organelles required for survival, as well as transport of parasite and host proteins to the digestive organelles to generate the building blocks for parasite growth. Several recent studies have shed light on the molecular mechanisms parasites utilise to transform the infected host cells, transport proteins to essential metabolic organelles and for biogenesis of organelles required for continuation of their life cycle. Here, we review key pathways of protein transport originating and branching from the endoplasmic reticulum, focusing on the essential roles of chaperones in these processes. Further, we highlight key gaps in our knowledge that prevents us from building a holistic view of protein trafficking in these deadly human pathogens.
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Affiliation(s)
- Anat Florentin
- Department of Cellular Biology, University of Georgia, Athens, Georgia, USA.,Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA
| | - David W Cobb
- Department of Cellular Biology, University of Georgia, Athens, Georgia, USA.,Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA
| | - Heather M Kudyba
- Department of Cellular Biology, University of Georgia, Athens, Georgia, USA.,Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA
| | - Vasant Muralidharan
- Department of Cellular Biology, University of Georgia, Athens, Georgia, USA.,Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA
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16
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Role of Plasmodium falciparum Protein GEXP07 in Maurer's Cleft Morphology, Knob Architecture, and P. falciparum EMP1 Trafficking. mBio 2020; 11:mBio.03320-19. [PMID: 32184257 PMCID: PMC7078486 DOI: 10.1128/mbio.03320-19] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The trafficking of the virulence antigen PfEMP1 and its presentation at the knob structures at the surface of parasite-infected RBCs are central to severe adhesion-related pathologies such as cerebral and placental malaria. This work adds to our understanding of how PfEMP1 is trafficked to the RBC membrane by defining the protein-protein interaction networks that function at the Maurer’s clefts controlling PfEMP1 loading and unloading. We characterize a protein needed for virulence protein trafficking and provide new insights into the mechanisms for host cell remodeling, parasite survival within the host, and virulence. The malaria parasite Plasmodium falciparum traffics the virulence protein P. falciparum erythrocyte membrane protein 1 (PfEMP1) to the surface of infected red blood cells (RBCs) via membranous organelles, known as the Maurer’s clefts. We developed a method for efficient enrichment of Maurer’s clefts and profiled the protein composition of this trafficking organelle. We identified 13 previously uncharacterized or poorly characterized Maurer’s cleft proteins. We generated transfectants expressing green fluorescent protein (GFP) fusions of 7 proteins and confirmed their Maurer’s cleft location. Using co-immunoprecipitation and mass spectrometry, we generated an interaction map of proteins at the Maurer’s clefts. We identified two key clusters that may function in the loading and unloading of PfEMP1 into and out of the Maurer’s clefts. We focus on a putative PfEMP1 loading complex that includes the protein GEXP07/CX3CL1-binding protein 2 (CBP2). Disruption of GEXP07 causes Maurer’s cleft fragmentation, aberrant knobs, ablation of PfEMP1 surface expression, and loss of the PfEMP1-mediated adhesion. ΔGEXP07 parasites have a growth advantage compared to wild-type parasites, and the infected RBCs are more deformable and more osmotically fragile.
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17
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Dantzler KW, Ma S, Ngotho P, Stone WJR, Tao D, Rijpma S, De Niz M, Nilsson Bark SK, Jore MM, Raaijmakers TK, Early AM, Ubaida-Mohien C, Lemgruber L, Campo JJ, Teng AA, Le TQ, Walker CL, Hermand P, Deterre P, Davies DH, Felgner P, Morlais I, Wirth DF, Neafsey DE, Dinglasan RR, Laufer M, Huttenhower C, Seydel K, Taylor T, Bousema T, Marti M. Naturally acquired immunity against immature Plasmodium falciparum gametocytes. Sci Transl Med 2019; 11:eaav3963. [PMID: 31167926 PMCID: PMC6653583 DOI: 10.1126/scitranslmed.aav3963] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Accepted: 04/05/2019] [Indexed: 12/11/2022]
Abstract
The recent decline in global malaria burden has stimulated efforts toward Plasmodium falciparum elimination. Understanding the biology of malaria transmission stages may provide opportunities to reduce or prevent onward transmission to mosquitoes. Immature P. falciparum transmission stages, termed stages I to IV gametocytes, sequester in human bone marrow before release into the circulation as mature stage V gametocytes. This process likely involves interactions between host receptors and potentially immunogenic adhesins on the infected red blood cell (iRBC) surface. Here, we developed a flow cytometry assay to examine immune recognition of live gametocytes of different developmental stages by naturally exposed Malawians. We identified strong antibody recognition of the earliest immature gametocyte-iRBCs (giRBCs) but not mature stage V giRBCs. Candidate surface antigens (n = 30), most of them shared between asexual- and gametocyte-iRBCs, were identified by mass spectrometry and mouse immunizations, as well as correlations between responses by protein microarray and flow cytometry. Naturally acquired responses to a subset of candidate antigens were associated with reduced asexual and gametocyte density, and plasma samples from malaria-infected individuals were able to induce immune clearance of giRBCs in vitro. Infected RBC surface expression of select candidate antigens was validated using specific antibodies, and genetic analysis revealed a subset with minimal variation across strains. Our data demonstrate that humoral immune responses to immature giRBCs and shared iRBC antigens are naturally acquired after malaria exposure. These humoral immune responses may have consequences for malaria transmission potential by clearing developing gametocytes, which could be leveraged for malaria intervention.
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Affiliation(s)
- Kathleen W Dantzler
- Department of Immunology and Infectious Disease, Harvard T.H. Chan School of Public Health, Boston, MA, USA
- Wellcome Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, UK
| | - Siyuan Ma
- Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Priscilla Ngotho
- Wellcome Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, UK
| | - Will J R Stone
- Radboud Institute for Health Sciences, Radboud University Medical Center, Netherlands
- Immunology and Infection Department, London School of Hygiene and Tropical Medicine, London, UK
| | - Dingyin Tao
- W. Harry Feinstone Department of Molecular Microbiology and Immunology and the Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD, USA
| | - Sanna Rijpma
- Radboud Institute for Health Sciences, Radboud University Medical Center, Netherlands
| | - Mariana De Niz
- Wellcome Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, UK
| | - Sandra K Nilsson Bark
- Department of Immunology and Infectious Disease, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Matthijs M Jore
- Radboud Institute for Health Sciences, Radboud University Medical Center, Netherlands
| | - Tonke K Raaijmakers
- Radboud Institute for Health Sciences, Radboud University Medical Center, Netherlands
| | | | | | - Leandro Lemgruber
- Wellcome Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, UK
| | | | | | | | | | - Patricia Hermand
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), UMR 1135, ERL CNRS 8255, F-75013 Paris, France
| | - Philippe Deterre
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), UMR 1135, ERL CNRS 8255, F-75013 Paris, France
| | - D Huw Davies
- Division of Infectious Diseases, Department of Medicine, University of California, Irvine, CA, USA
| | - Phil Felgner
- Division of Infectious Diseases, Department of Medicine, University of California, Irvine, CA, USA
| | - Isabelle Morlais
- UMR MIVEGEC UM1-CNRS 5290-IRD 224, Institut de Recherche pour le Développement, Montpellier Cedex, France
| | - Dyann F Wirth
- Department of Immunology and Infectious Disease, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | | | - Rhoel R Dinglasan
- W. Harry Feinstone Department of Molecular Microbiology and Immunology and the Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
- Emerging Pathogens Institute, Department of Infectious Diseases and Immunology, University of Florida College of Veterinary Medicine, Gainesville, FL, USA
| | - Miriam Laufer
- Division of Malaria Research, Institute for Global Health, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Curtis Huttenhower
- Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Karl Seydel
- Department of Osteopathic Medical Specialties, College of Osteopathic Medicine, Michigan State University, East Lansing, MI, USA
- Blantyre Malaria Project, University of Malawi College of Medicine, Blantyre, Malawi
| | - Terrie Taylor
- Department of Osteopathic Medical Specialties, College of Osteopathic Medicine, Michigan State University, East Lansing, MI, USA
- Blantyre Malaria Project, University of Malawi College of Medicine, Blantyre, Malawi
| | - Teun Bousema
- Radboud Institute for Health Sciences, Radboud University Medical Center, Netherlands.
- Immunology and Infection Department, London School of Hygiene and Tropical Medicine, London, UK
| | - Matthias Marti
- Department of Immunology and Infectious Disease, Harvard T.H. Chan School of Public Health, Boston, MA, USA.
- Wellcome Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, UK
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18
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Daniyan MO, Ojo OT. In silico identification and evaluation of potential interaction of Azadirachta indica phytochemicals with Plasmodium falciparum heat shock protein 90. J Mol Graph Model 2019; 87:144-164. [DOI: 10.1016/j.jmgm.2018.11.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 10/31/2018] [Accepted: 11/30/2018] [Indexed: 01/13/2023]
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19
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Siau A, Huang X, Loh HP, Zhang N, Meng W, Sze SK, Renia L, Preiser P. Immunomic Identification of Malaria Antigens Associated With Protection in Mice. Mol Cell Proteomics 2019; 18:837-853. [PMID: 30718293 DOI: 10.1074/mcp.ra118.000997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 01/22/2019] [Indexed: 11/06/2022] Open
Abstract
Efforts to develop vaccines against malaria represent a major research target. The observations that 1) sterile protection can be obtained when the host is exposed to live parasites and 2) the immunity against blood stage parasite is principally mediated by protective antibodies suggest that a protective vaccine is feasible. However, only a small number of proteins have been investigated so far and most of the Plasmodium proteome has yet to be explored. To date, only few immunodominant antigens have emerged for testing in clinical trials but no formulation has led to substantial protection in humans. The nature of parasite molecules associated with protection remains elusive. Here, immunomic screening of mice immune sera with different protection efficiencies against the whole parasite proteome allowed us to identify a large repertoire of antigens validated by screening a library expressing antigens. The calculation of weighted scores reflecting the likelihood of protection of each antigen using five predictive criteria derived from immunomic and proteomic data sets, highlighted a priority list of protective antigens. Altogether, the approach sheds light on conserved antigens across Plasmodium that are amenable to targeting by the host immune system upon merozoite invasion and blood stage development. Most of these antigens have preliminary protection data but have not been widely considered as candidate for vaccine trials, opening new perspectives that overcome the limited choice of immunodominant, poorly protective vaccines currently being the focus of malaria vaccine researches.
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Affiliation(s)
- Anthony Siau
- From the ‡Nanyang Technological University, School of Biological Sciences, Singapore;.
| | - Ximei Huang
- From the ‡Nanyang Technological University, School of Biological Sciences, Singapore;; From the ‡Nanyang Technological University, School of Biological Sciences, Singapore
| | - Han Ping Loh
- From the ‡Nanyang Technological University, School of Biological Sciences, Singapore;; From the ‡Nanyang Technological University, School of Biological Sciences, Singapore
| | - Neng Zhang
- From the ‡Nanyang Technological University, School of Biological Sciences, Singapore
| | - Wei Meng
- From the ‡Nanyang Technological University, School of Biological Sciences, Singapore
| | - Siu Kwan Sze
- From the ‡Nanyang Technological University, School of Biological Sciences, Singapore
| | - Laurent Renia
- §Singapore Immunology Network (SIgN), A*STAR, Biopolis, Singapore
| | - Peter Preiser
- From the ‡Nanyang Technological University, School of Biological Sciences, Singapore;.
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20
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Gonçalves DDS, Ferreira MDS, Liedke SC, Gomes KX, de Oliveira GA, Leão PEL, Cesar GV, Seabra SH, Cortines JR, Casadevall A, Nimrichter L, Domont GB, Junqueira MR, Peralta JM, Guimaraes AJ. Extracellular vesicles and vesicle-free secretome of the protozoa Acanthamoeba castellanii under homeostasis and nutritional stress and their damaging potential to host cells. Virulence 2018; 9:818-836. [PMID: 29560793 PMCID: PMC5955443 DOI: 10.1080/21505594.2018.1451184] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2018] [Accepted: 03/06/2018] [Indexed: 12/14/2022] Open
Abstract
Acanthamoeba castellanii (Ac) are ubiquitously distributed in nature, and by contaminating medical devices such as heart valves and contact lenses, they cause a broad range of clinical presentations to humans. Although several molecules have been described to play a role in Ac pathogenesis, including parasite host-tissue invasion and escaping of host-defense, little information is available on their mechanisms of secretion. Herein, we describe the molecular components secreted by Ac, under different protein availability conditions to simulate host niches. Ac extracellular vesicles (EVs) were morphologically and biochemically characterized. Dynamic light scattering analysis of Ac EVs identified polydisperse populations, which correlated to electron microscopy measurements. High-performance thin liquid chromatography of Ac EVs identified phospholipids, steryl-esters, sterol and free-fatty acid, the last two also characterized by GC-MS. Secretome composition (EVs and EVs-free supernatants) was also determined and proteins biological functions classified. In peptone-yeast-glucose (PYG) medium, a total of 179 proteins were identified (21 common proteins, 89 exclusive of EVs and 69 in EVs-free supernatant). In glucose alone, 205 proteins were identified (134 in EVs, 14 common and 57 proteins in EVs-free supernatant). From those, stress response, oxidative and protein and amino acid metabolism proteins prevailed. Qualitative differences were observed on carbohydrate metabolism enzymes from Krebs cycle and pentose phosphate shunt. Serine proteases and metalloproteinases predominated. Analysis of the cytotoxicity of Ac EVs (upon uptake) and EVs-free supernatant to epithelial and glioblastoma cells revealed a dose-dependent effect. Therefore, the Ac secretome differs depending on nutrient conditions, and is also likely to vary during infection.
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Affiliation(s)
- Diego de Souza Gonçalves
- Departamento de Microbiologia e Parasitologia, Instituto Biomédico, Universidade Federal Fluminense, Niterói, Brazil
| | - Marina da Silva Ferreira
- Departamento de Imunologia, Instituto de Microbiologia Professor Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Susie Coutinho Liedke
- Departamento de Imunologia, Instituto de Microbiologia Professor Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Kamilla Xavier Gomes
- Departamento de Microbiologia e Parasitologia, Instituto Biomédico, Universidade Federal Fluminense, Niterói, Brazil
| | - Gabriel Afonso de Oliveira
- Departamento de Microbiologia e Parasitologia, Instituto Biomédico, Universidade Federal Fluminense, Niterói, Brazil
| | - Pedro Ernesto Lopes Leão
- Laboratório de Glicobiologia de Eucariotos, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Gabriele Vargas Cesar
- Laboratório de Glicobiologia de Eucariotos, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Sergio H. Seabra
- Laboratório de Tecnologia em Cultura de Células, Centro Universitário Estadual da Zona Oeste (UEZO), Rio de Janeiro, Brazil
| | - Juliana Reis Cortines
- Departamento de Virologia, Instituto de Microbiologia Professor Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Arturo Casadevall
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Leonardo Nimrichter
- Laboratório de Glicobiologia de Eucariotos, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Gilberto Barbosa Domont
- Departamento de Bioquímica, Instituto de Química, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Magno Rodrigues Junqueira
- Departamento de Bioquímica, Instituto de Química, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Jose Mauro Peralta
- Departamento de Imunologia, Instituto de Microbiologia Professor Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Allan J. Guimaraes
- Departamento de Microbiologia e Parasitologia, Instituto Biomédico, Universidade Federal Fluminense, Niterói, Brazil
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21
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Kaur J, Kumar V, Singh AP, Singh V, Bisht A, Dube T, Panda JJ, Behl A, Mishra PC, Hora R. Plasmodium falciparumprotein ‘PfJ23’ hosts distinct binding sites for major virulence factor ‘PfEMP1’ and Maurer's cleft marker ‘PfSBP1’. Pathog Dis 2018; 76:5255127. [DOI: 10.1093/femspd/fty090] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Accepted: 12/19/2018] [Indexed: 01/09/2023] Open
Affiliation(s)
- Jasweer Kaur
- Department of Molecular Biology and Biochemistry, Guru Nanak Dev University, Amritsar, Punjab, India
| | - Vikash Kumar
- Department of Molecular Biology and Biochemistry, Guru Nanak Dev University, Amritsar, Punjab, India
| | - Amrit Pal Singh
- Department of Pharmaceutical sciences, Guru Nanak Dev University, Amritsar, Punjab, India
| | - Vineeta Singh
- National Institute of Malaria Research, Sector 8 Dwarka, New Delhi, 110077 India. 4. Institute of Nanoscience and Technology, Habitat Centre, Phase 10, Sector 64, Sahibzada Ajit Singh Nagar, Punjab 160062 India
| | - Anjali Bisht
- Institute of Nanoscience and Technology, Mohali, Punjab, India
| | - Taru Dube
- Institute of Nanoscience and Technology, Mohali, Punjab, India
| | | | - Ankita Behl
- Department of Biotechnology, Guru Nanak Dev University, Amritsar, Punjab, India
| | | | - Rachna Hora
- Department of Molecular Biology and Biochemistry, Guru Nanak Dev University, Amritsar, Punjab, India
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22
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Arredondo SA, Swearingen KE, Martinson T, Steel R, Dankwa DA, Harupa A, Camargo N, Betz W, Vigdorovich V, Oliver BG, Kangwanrangsan N, Ishino T, Sather N, Mikolajczak S, Vaughan AM, Torii M, Moritz RL, Kappe SHI. The Micronemal Plasmodium Proteins P36 and P52 Act in Concert to Establish the Replication-Permissive Compartment Within Infected Hepatocytes. Front Cell Infect Microbiol 2018; 8:413. [PMID: 30547015 PMCID: PMC6280682 DOI: 10.3389/fcimb.2018.00413] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Accepted: 11/08/2018] [Indexed: 12/15/2022] Open
Abstract
Within the liver, Plasmodium sporozoites traverse cells searching for a "suitable" hepatocyte, invading these cells through a process that results in the formation of a parasitophorous vacuole (PV), within which the parasite undergoes intracellular replication as a liver stage. It was previously established that two members of the Plasmodium s48/45 protein family, P36 and P52, are essential for productive invasion of host hepatocytes by sporozoites as their simultaneous deletion results in growth-arrested parasites that lack a PV. Recent studies point toward a pathway of entry possibly involving the interaction of P36 with hepatocyte receptors EphA2, CD81, and SR-B1. However, the relationship between P36 and P52 during sporozoite invasion remains unknown. Here we show that parasites with a single P52 or P36 gene deletion each lack a PV after hepatocyte invasion, thereby pheno-copying the lack of a PV observed for the P52/P36 dual gene deletion parasite line. This indicates that both proteins are equally important in the establishment of a PV and act in the same pathway. We created a Plasmodium yoelii P36mCherry tagged parasite line that allowed us to visualize the subcellular localization of P36 and found that it partially co-localizes with P52 in the sporozoite secretory microneme organelles. Furthermore, through co-immunoprecipitation studies in vivo, we determined that P36 and P52 form a protein complex in sporozoites, indicating a concerted function for both proteins within the PV formation pathway. However, upon sporozoite stimulation, only P36 was released as a secreted protein while P52 was not. Our results support a model in which the putatively glycosylphosphatidylinositol (GPI)-anchored P52 may serve as a scaffold to facilitate the interaction of secreted P36 with the host cell during sporozoite invasion of hepatocytes.
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Affiliation(s)
- Silvia A. Arredondo
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, United States
| | | | - Thomas Martinson
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, United States
| | - Ryan Steel
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, United States
| | - Dorender A. Dankwa
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, United States
| | - Anke Harupa
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, United States
| | - Nelly Camargo
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, United States
| | - William Betz
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, United States
| | - Vladimir Vigdorovich
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, United States
| | - Brian G. Oliver
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, United States
| | - Niwat Kangwanrangsan
- Department of Pathobiology, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Tomoko Ishino
- Department of Molecular Parasitology, Proteo-Science Center, Ehime University, Shitsukawa, Toon, Japan
| | - Noah Sather
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, United States
| | - Sebastian Mikolajczak
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, United States
| | - Ashley M. Vaughan
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, United States
| | - Motomi Torii
- Department of Molecular Parasitology, Proteo-Science Center, Ehime University, Shitsukawa, Toon, Japan
| | | | - Stefan H. I. Kappe
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, United States
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23
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Swearingen KE, Lindner SE. Plasmodium Parasites Viewed through Proteomics. Trends Parasitol 2018; 34:945-960. [PMID: 30146456 PMCID: PMC6204299 DOI: 10.1016/j.pt.2018.08.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Revised: 08/02/2018] [Accepted: 08/05/2018] [Indexed: 12/14/2022]
Abstract
Early sequencing efforts that produced the genomes of several species of malaria parasites (Plasmodium genus) propelled transcriptomic and proteomic efforts. In this review, we focus upon some of the exciting proteomic advances from studies of Plasmodium parasites over approximately the past decade. With improvements to both instrumentation and data-processing capabilities, long-standing questions about the forms and functions of these important pathogens are rapidly being answered. In particular, global and subcellular proteomics, quantitative proteomics, and the detection of post-translational modifications have all revealed important features of the parasite's regulatory mechanisms. Finally, we provide our perspectives on future applications of proteomics to Plasmodium research, as well as suggestions for further improvement through standardization of data deposition, analysis, and accessibility.
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Affiliation(s)
- Kristian E Swearingen
- Institute for Systems Biology, Seattle, WA 98109, USA; Center for Infectious Disease Research, Seattle, WA 98109, USA
| | - Scott E Lindner
- Department of Biochemistry and Molecular Biology, Center for Malaria Research, Pennsylvania State University, University Park, PA 16802, USA.
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24
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Zhang M, Faou P, Maier AG, Rug M. Plasmodium falciparum exported protein PFE60 influences Maurer’s clefts architecture and virulence complex composition. Int J Parasitol 2018; 48:83-95. [DOI: 10.1016/j.ijpara.2017.09.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Revised: 08/20/2017] [Accepted: 09/06/2017] [Indexed: 11/30/2022]
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25
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Cabral FJ, Vianna LG, Medeiros MM, Carlos BC, Martha RD, Silva NM, Silva LHPD, Stabeli RG, Wunderlich G. Immunoproteomics of Plasmodium falciparum-infected red blood cell membrane fractions. Mem Inst Oswaldo Cruz 2017; 112:850-856. [PMID: 29211247 PMCID: PMC5719555 DOI: 10.1590/0074-02760170041] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Accepted: 06/30/2017] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND The surface of infected red blood cells (iRBCs) has been widely investigated
because of the molecular complexity and pathogenesis mechanisms involved.
Asymptomatic individuals are important in the field because they can
perpetuate transmission as natural reservoirs and present a challenge for
diagnosing malaria because of their low levels of circulating parasites.
Recent studies of iRBC antibody recognition have shown that responses are
quantitatively similar in symptomatic and asymptomatic infections, but no
studies have characterised the plasmodial proteins targeted by this
response. OBJECTIVES Our main objective was to identify Plasmodium falciparum
proteins associated with iRBC ghosts recognised by antibodies in the sera of
symptomatic and asymptomatic individuals in the Brazilian Amazon. METHODS We collected symptomatic and asymptomatic sera from patients residing in the
Brazilian Amazon and P. falciparum iRBC ghosts to identify
the proteins involved in natural antibody recognition by 2D-electrophoresis,
western blotting, and high- resolution mass spectrometry. FINDINGS 2D gel-based immunoproteome analysis using symptomatic and asymptomatic sera
identified 11 proteins with at least one unique peptide, such as chaperones
HSP70-1 and HSP70-x, which likely are components of the secretion
machinery/PTEX translocon. PfEMP1 is involved in antigenic variation in
symptomatic infections and we found putative membrane proteins whose
functions are unknown. MAIN FINDINGS Our results suggest a potential role of old and new proteins, such as
antigenic variation proteins, iRBC remodelling, and membrane proteins, with
no assigned functions related to the immune response against P.
falciparum, providing insights into the pathogenesis,
erythrocyte remodelling, and secretion machinery important for alternative
diagnosis and/or malaria therapy.
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Affiliation(s)
- Fernanda J Cabral
- Universidade Estadual de Campinas, Instituto de Biologia, Departamento de Biologia Animal, Campinas, SP, Brasil.,Universidade de São Paulo, Instituto de Ciências Biomédicas, Departamento de Parasitologia, São Paulo, SP, Brasil
| | | | - Marcia M Medeiros
- Universidade de São Paulo, Instituto de Ciências Biomédicas, Departamento de Parasitologia, São Paulo, SP, Brasil.,Universidade Nova de Lisboa, Instituto de Higiene e Medicina Tropical, Lisboa, Portugal
| | - Bianca Cechetto Carlos
- Universidade de São Paulo, Instituto de Ciências Biomédicas, Departamento de Parasitologia, São Paulo, SP, Brasil
| | | | - Nadia Maria Silva
- Universidade Estadual de Campinas, Instituto de Biologia, Departamento de Biologia Animal, Campinas, SP, Brasil
| | | | | | - Gerhard Wunderlich
- Universidade de São Paulo, Instituto de Ciências Biomédicas, Departamento de Parasitologia, São Paulo, SP, Brasil
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26
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Sherling ES, van Ooij C. Host cell remodeling by pathogens: the exomembrane system in Plasmodium-infected erythrocytes. FEMS Microbiol Rev 2017; 40:701-21. [PMID: 27587718 PMCID: PMC5007283 DOI: 10.1093/femsre/fuw016] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/18/2016] [Indexed: 12/22/2022] Open
Abstract
Malaria is caused by infection of erythrocytes by parasites of the genus Plasmodium. To survive inside erythrocytes, these parasites induce sweeping changes within the host cell, one of the most dramatic of which is the formation of multiple membranous compartments, collectively referred to as the exomembrane system. As an uninfected mammalian erythrocyte is devoid of internal membranes, the parasite must be the force and the source behind the formation of these compartments. Even though the first evidence of the presence these of internal compartments was obtained over a century ago, their functions remain mostly unclear, and in some cases completely unknown, and the mechanisms underlying their formation are still mysterious. In this review, we provide an overview of the different parts of the exomembrane system, describing the parasitophorous vacuole, the tubovesicular network, Maurer's clefts, the caveola-vesicle complex, J dots and other mobile compartments, and the small vesicles that have been observed in Plasmodium-infected cells. Finally, we combine the data into a simplified view of the exomembrane system and its relation to the alterations of the host erythrocyte. Plasmodium parasites remodel the host erythrocyte in various ways, including the formation of several membranous compartments, together referred to as the exomembrane system, within the erythrocyte cytosol that together are key to the sweeping changes in the host cell.
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Affiliation(s)
- Emma S Sherling
- The Francis Crick Institute, Mill Hill Laboratory, Mill Hill, London NW7 1AA, UK Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | - Christiaan van Ooij
- The Francis Crick Institute, Mill Hill Laboratory, Mill Hill, London NW7 1AA, UK
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27
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Nilsson Bark SK, Ahmad R, Dantzler K, Lukens AK, De Niz M, Szucs MJ, Jin X, Cotton J, Hoffmann D, Bric-Furlong E, Oomen R, Parrington M, Milner D, Neafsey DE, Carr SA, Wirth DF, Marti M. Quantitative Proteomic Profiling Reveals Novel Plasmodium falciparum Surface Antigens and Possible Vaccine Candidates. Mol Cell Proteomics 2017; 17:43-60. [PMID: 29162636 DOI: 10.1074/mcp.ra117.000076] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Revised: 09/20/2017] [Indexed: 12/30/2022] Open
Abstract
Despite recent efforts toward control and elimination, malaria remains a major public health problem worldwide. Plasmodium falciparum resistance against artemisinin, used in front line combination drugs, is on the rise, and the only approved vaccine shows limited efficacy. Combinations of novel and tailored drug and vaccine interventions are required to maintain the momentum of the current malaria elimination program. Current evidence suggests that strain-transcendent protection against malaria infection can be achieved using whole organism vaccination or with a polyvalent vaccine covering multiple antigens or epitopes. These approaches have been successfully applied to the human-infective sporozoite stage. Both systemic and tissue-specific pathology during infection with the human malaria parasite P. falciparum is caused by asexual blood stages. Tissue tropism and vascular sequestration are the result of specific binding interactions between antigens on the parasite-infected red blood cell (pRBC) surface and endothelial receptors. The major surface antigen and parasite ligand binding to endothelial receptors, PfEMP1 is encoded by about 60 variants per genome and shows high sequence diversity across strains. Apart from PfEMP1 and three additional variant surface antigen families RIFIN, STEVOR, and SURFIN, systematic analysis of the infected red blood cell surface is lacking. Here we present the most comprehensive proteomic investigation of the parasitized red blood cell surface so far. Apart from the known variant surface antigens, we identified a set of putative single copy surface antigens with low sequence diversity, several of which are validated in a series of complementary experiments. Further functional and immunological investigation is underway to test these novel P. falciparum blood stage proteins as possible vaccine candidates.
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Affiliation(s)
- Sandra K Nilsson Bark
- From the ‡Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts 02115
| | - Rushdy Ahmad
- §The Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142
| | - Kathleen Dantzler
- From the ‡Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts 02115.,¶Wellcome Centre for Molecular Parasitology, University of Glasgow, Glasgow G12 8TA, UK
| | - Amanda K Lukens
- From the ‡Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts 02115.,§The Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142
| | - Mariana De Niz
- ¶Wellcome Centre for Molecular Parasitology, University of Glasgow, Glasgow G12 8TA, UK
| | - Matthew J Szucs
- §The Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142
| | - Xiaoying Jin
- ‖Sanofi Biopharmaceutics Development, Framingham, Massachusetts 02142
| | - Joanne Cotton
- ‖Sanofi Biopharmaceutics Development, Framingham, Massachusetts 02142
| | | | | | - Ray Oomen
- **Sanofi Pasteur Biologics, Cambridge, Massachusetts 02139
| | | | - Dan Milner
- From the ‡Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts 02115.,‡‡Department of Pathology, Brigham and Women's Hospital, Boston, Massachusetts 02115
| | - Daniel E Neafsey
- §The Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142
| | - Steven A Carr
- §The Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142
| | - Dyann F Wirth
- From the ‡Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts 02115.,§The Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142
| | - Matthias Marti
- From the ‡Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts 02115; .,¶Wellcome Centre for Molecular Parasitology, University of Glasgow, Glasgow G12 8TA, UK
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28
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Jha P, Laskar S, Dubey S, Bhattacharyya MK, Bhattacharyya S. Plasmodium Hsp40 and human Hsp70: A potential cochaperone-chaperone complex. Mol Biochem Parasitol 2017; 214:10-13. [PMID: 28322872 DOI: 10.1016/j.molbiopara.2017.03.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Revised: 02/25/2017] [Accepted: 03/08/2017] [Indexed: 11/27/2022]
Abstract
Out of the total forty four members of Plasmodium falciparum Hsp40 protein family, nineteen of them possess a PEXEL motif, and are predicted to be exported into the cytosol of an infected RBC. It is speculated that the human Hsp70 (hHsp70), which resides into the cytosol of the host erythrocyte, along with the exported PfHsp40s assists in the folding of parasitic proteins, thus playing a crucial role in the establishment of virulence. However, till date no experimental evidence supports this hypothesis. Our work establishes that the PEXEL motifs containing Type II PfDNAJ proteins specifically interact with hHsp70 (HSPA1A). It suggests that there exists a specific factor in PfDNAJ that determines the choice of cognate Hsp70. This opens up an interesting avenue of malaria research.
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Affiliation(s)
- Payal Jha
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Telangana, 500046, India
| | - Shyamasree Laskar
- Department of Biotechnology and Bioinformatics, School of Life Sciences, University of Hyderabad, Telangana, 500046, India
| | - Swati Dubey
- Department of Biotechnology and Bioinformatics, School of Life Sciences, University of Hyderabad, Telangana, 500046, India
| | - Mrinal K Bhattacharyya
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Telangana, 500046, India.
| | - Sunanda Bhattacharyya
- Department of Biotechnology and Bioinformatics, School of Life Sciences, University of Hyderabad, Telangana, 500046, India.
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29
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Counihan NA, Chisholm SA, Bullen HE, Srivastava A, Sanders PR, Jonsdottir TK, Weiss GE, Ghosh S, Crabb BS, Creek DJ, Gilson PR, de Koning-Ward TF. Plasmodium falciparum parasites deploy RhopH2 into the host erythrocyte to obtain nutrients, grow and replicate. eLife 2017; 6. [PMID: 28252383 PMCID: PMC5365316 DOI: 10.7554/elife.23217] [Citation(s) in RCA: 83] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2016] [Accepted: 02/26/2017] [Indexed: 11/13/2022] Open
Abstract
Plasmodium falciparum parasites, the causative agents of malaria, modify their host erythrocyte to render them permeable to supplementary nutrient uptake from the plasma and for removal of toxic waste. Here we investigate the contribution of the rhoptry protein RhopH2, in the formation of new permeability pathways (NPPs) in Plasmodium-infected erythrocytes. We show RhopH2 interacts with RhopH1, RhopH3, the erythrocyte cytoskeleton and exported proteins involved in host cell remodeling. Knockdown of RhopH2 expression in cycle one leads to a depletion of essential vitamins and cofactors and decreased de novo synthesis of pyrimidines in cycle two. There is also a significant impact on parasite growth, replication and transition into cycle three. The uptake of solutes that use NPPs to enter erythrocytes is also reduced upon RhopH2 knockdown. These findings provide direct genetic support for the contribution of the RhopH complex in NPP activity and highlight the importance of NPPs to parasite survival.
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Affiliation(s)
| | | | | | - Anubhav Srivastava
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Australia
| | | | - Thorey K Jonsdottir
- Burnet Institute, Melbourne, Australia.,Department of Medicine, University of Melbourne, Parkville, Australia
| | | | - Sreejoyee Ghosh
- School of Medicine, Deakin University, Waurn Ponds, Australia
| | - Brendan S Crabb
- Burnet Institute, Melbourne, Australia.,Department of Medicine, University of Melbourne, Parkville, Australia.,Monash University, Melbourne, Australia
| | - Darren J Creek
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Australia
| | - Paul R Gilson
- Burnet Institute, Melbourne, Australia.,Monash University, Melbourne, Australia
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30
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Receptor for Activated C-Kinase 1 (PfRACK1) is required for Plasmodium falciparum intra-erythrocytic proliferation. Mol Biochem Parasitol 2016; 211:62-66. [PMID: 27732881 DOI: 10.1016/j.molbiopara.2016.10.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Revised: 10/05/2016] [Accepted: 10/08/2016] [Indexed: 11/24/2022]
Abstract
Emerging resistance to current anti-malarials necessitates a more detailed understanding of the biological processes of Plasmodium falciparum proliferation, thus allowing identification of new drug targets. The well-conserved protein Receptor for Activated C-Kinase 1 (RACK1) was originally identified in mammalian cells as an anchoring protein for protein kinase C (PKC) and has since been shown to be important for cell migration, cytokinesis, transcription, epigenetics, and protein translation. The P. falciparum ortholog, PfRACK1, is expressed in blood stages of the parasite and is diffusely localized in the parasite cytoplasm. Using a destabilizing domain to allow inducible knockdown of the endogenous protein level, we evaluated the requirement for PfRACK1 during blood-stage replication. Following destabilization, the parasites demonstrate a nearly complete growth arrest at the trophozoite stage. The essential nature of PfRACK1 suggests that the protein itself or the pathways regulated by the protein are potential targets for novel anti-malarial therapeutics.
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31
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Plasmodium Helical Interspersed Subtelomeric (PHIST) Proteins, at the Center of Host Cell Remodeling. Microbiol Mol Biol Rev 2016; 80:905-27. [PMID: 27582258 DOI: 10.1128/mmbr.00014-16] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
During the asexual cycle, Plasmodium falciparum extensively remodels the human erythrocyte to make it a suitable host cell. A large number of exported proteins facilitate this remodeling process, which causes erythrocytes to become more rigid, cytoadherent, and permeable for nutrients and metabolic products. Among the exported proteins, a family of 89 proteins, called the Plasmodium helical interspersed subtelomeric (PHIST) protein family, has been identified. While also found in other Plasmodium species, the PHIST family is greatly expanded in P. falciparum. Although a decade has passed since their first description, to date, most PHIST proteins remain uncharacterized and are of unknown function and localization within the host cell, and there are few data on their interactions with other host or parasite proteins. However, over the past few years, PHIST proteins have been mentioned in the literature at an increasing rate owing to their presence at various localizations within the infected erythrocyte. Expression of PHIST proteins has been implicated in molecular and cellular processes such as the surface display of PfEMP1, gametocytogenesis, changes in cell rigidity, and also cerebral and pregnancy-associated malaria. Thus, we conclude that PHIST proteins are central to host cell remodeling, but despite their obvious importance in pathology, PHIST proteins seem to be understudied. Here we review current knowledge, shed light on the definition of PHIST proteins, and discuss these proteins with respect to their localization and probable function. We take into consideration interaction studies, microarray analyses, or data from blood samples from naturally infected patients to combine all available information on this protein family.
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32
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Siau A, Huang X, Weng M, Sze SK, Preiser PR. Proteome mapping of Plasmodium: identification of the P. yoelii remodellome. Sci Rep 2016; 6:31055. [PMID: 27503796 PMCID: PMC4977464 DOI: 10.1038/srep31055] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 07/13/2016] [Indexed: 11/17/2022] Open
Abstract
Plasmodium associated virulence in the host is linked to extensive remodelling of the host erythrocyte by parasite proteins that form the “remodellome”. However, without a common motif or structure available to identify these proteins, little is known about the proteins that are destined to reside in the parasite periphery, the host-cell cytoplasm and/or the erythrocyte membrane. Here, the subcellular fractionation of erythrocytic P. yoelii at trophozoite and schizont stage along with label-free quantitative LC-MS/MS analysis of the whole proteome, revealed a proteome of 1335 proteins. Differential analysis of the relative abundance of these proteins across the subcellular compartments allowed us to map their locations, independently of their predicted features. These results, along with literature data and in vivo validation of 61 proteins enabled the identification of a remodellome of 184 proteins. This approach identified a significant number of conserved remodelling proteins across plasmodium that likely represent key conserved functions in the parasite and provides new insights into parasite evolution and biology.
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Affiliation(s)
- Anthony Siau
- Nanyang Technological University, School of Biological Sciences, 637551, Singapore
| | - Ximei Huang
- Nanyang Technological University, School of Biological Sciences, 637551, Singapore
| | - Mei Weng
- Nanyang Technological University, School of Biological Sciences, 637551, Singapore
| | - Siu Kwan Sze
- Nanyang Technological University, School of Biological Sciences, 637551, Singapore
| | - Peter R Preiser
- Nanyang Technological University, School of Biological Sciences, 637551, Singapore
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33
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Huang JM, Lin WC, Li SC, Shih MH, Chan WC, Shin JW, Huang FC. Comparative proteomic analysis of extracellular secreted proteins expressed by two pathogenic Acanthamoeba castellanii clinical isolates and a non-pathogenic ATCC strain. Exp Parasitol 2016; 166:60-7. [PMID: 26995533 DOI: 10.1016/j.exppara.2016.03.018] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Revised: 01/15/2016] [Accepted: 03/14/2016] [Indexed: 01/09/2023]
Abstract
Acanthamoeba keratitis (AK) is a serious ocular disease caused by pathogenic Acanthamoeba gaining entry through wounds in the corneal injury; generally, patients at risk for contracting AK wear contact lenses, usually over a long period of time. Moreover, pathogenic Acanthamoeba causes serious consequences: it makes the cornea turbid and difficult to operate on, including procedures such as enucleation of the eyeball. At present, diagnosis of this disease is not straightforward, and treatment is very demanding. We have established the comparative transcriptome and extracellular secreted proteomic database according to the non-pathogenic strain ATCC 30010 and the pathogenic strains NCKU_B and NCKU_D. We identified 44 secreted proteins successfully, 10 consensus secreted proteins and 34 strain-specific secreted proteins. These proteins may provide targets for therapy and immuno-diagnosis of Acanthamoeba infections. This study shows a suitable approach to identify secreted proteins in Acanthamoeba and provides new perspectives for the study of molecules potentially involved in the AK.
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Affiliation(s)
- Jian-Ming Huang
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Wei-Chen Lin
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Department of Parasitology, National Cheng Kung University, Tainan, Taiwan
| | - Sung-Chou Li
- Genomics and Proteomics Core Laboratory, Department of Medical Research, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Min-Hsiu Shih
- Department of Ophthalmology, National Cheng Kung University Hospital, Tainan, Taiwan
| | - Wen-Ching Chan
- Genomics and Proteomics Core Laboratory, Department of Medical Research, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Jyh-Wei Shin
- Department of Parasitology, National Cheng Kung University, Tainan, Taiwan
| | - Fu-Chin Huang
- Department of Ophthalmology, National Cheng Kung University Hospital, Tainan, Taiwan.
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34
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Malaria Parasite Proteins and Their Role in Alteration of the Structure and Function of Red Blood Cells. ADVANCES IN PARASITOLOGY 2015; 91:1-86. [PMID: 27015947 DOI: 10.1016/bs.apar.2015.09.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Malaria, caused by Plasmodium spp., continues to be a major threat to human health and a significant cause of socioeconomic hardship in many countries. Almost half of the world's population live in malaria-endemic regions and many of them suffer one or more, often life-threatening episodes of malaria every year, the symptoms of which are attributable to replication of the parasite within red blood cells (RBCs). In the case of Plasmodium falciparum, the species responsible for most malaria-related deaths, parasite replication within RBCs is accompanied by striking alterations to the morphological, biochemical and biophysical properties of the host cell that are essential for the parasites' survival. To achieve this, the parasite establishes a unique and extensive protein export network in the infected RBC, dedicating at least 6% of its genome to the process. Understanding the full gamut of proteins involved in this process and the mechanisms by which P. falciparum alters the structure and function of RBCs is important both for a more complete understanding of the pathogenesis of malaria and for development of new therapeutic strategies to prevent or treat this devastating disease. This review focuses on what is currently known about exported parasite proteins, their interactions with the RBC and their likely pathophysiological consequences.
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Skorokhod OA, Davalos-Schafler D, Gallo V, Valente E, Ulliers D, Notarpietro A, Mandili G, Novelli F, Persico M, Taglialatela-Scafati O, Arese P, Schwarzer E. Oxidative stress-mediated antimalarial activity of plakortin, a natural endoperoxide from the tropical sponge Plakortis simplex. Free Radic Biol Med 2015; 89:624-37. [PMID: 26459031 DOI: 10.1016/j.freeradbiomed.2015.10.399] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Revised: 09/27/2015] [Accepted: 10/07/2015] [Indexed: 10/22/2022]
Abstract
Plakortin, a polyketide endoperoxide from the sponge Plakortis simplex has antiparasitic activity against P. falciparum. Similar to artemisinin, its activity depends on the peroxide functionality. Plakortin induced stage-, dose- and time-dependent morphologic anomalies, early maturation delay, ROS generation and lipid peroxidation in the parasite. Ring damage by 1 and 10 µM plakortin led to parasite death before schizogony at 20 and 95%, respectively. Treatment of late schizonts with 1, 2, 5 and 10 µM plakortin resulted in decreased reinfection rates by 30, 50, 61 and 65%, respectively. In both rings and trophozoites, plakortin induced a dose- and time-dependent ROS production as well as a significant lipid peroxidation and up to 4-fold increase of the lipoperoxide breakdown product 4-hydroxynonenal (4-HNE). Antioxidants and the free radical scavengers trolox and N-acetylcysteine significantly attenuated the parasite damage. Plakortin generated 4-HNE conjugates with the P. falciparum proteins: heat shock protein Hsp70-1, endoplasmatic reticulum-standing Hsp70-2 (BiP analogue), V-type proton ATPase catalytic subunit A, enolase, the putative vacuolar protein sorting-associated protein 11, and the dynein heavy chain-like protein, whose specific binding sites were identified by mass spectrometry. These proteins are crucially involved in protein trafficking, transmembrane and vesicular transport and parasite survival. We hypothesize that binding of 4-HNE to functionally relevant parasite proteins may explain the observed plakortin-induced morphologic aberrations and parasite death. The identification of 4-HNE-protein conjugates may generate a novel paradigm to explain the mechanism of action of pro-oxidant, peroxide-based antimalarials such as plakortin, artemisinins and synthetic endoperoxides.
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Affiliation(s)
- Oleksii A Skorokhod
- Department of Oncology, University of Torino, Via Santena 5bis, 10126 Torino, Italy.
| | | | - Valentina Gallo
- Department of Oncology, University of Torino, Via Santena 5bis, 10126 Torino, Italy.
| | - Elena Valente
- Department of Oncology, University of Torino, Via Santena 5bis, 10126 Torino, Italy.
| | - Daniela Ulliers
- Department of Oncology, University of Torino, Via Santena 5bis, 10126 Torino, Italy.
| | - Agata Notarpietro
- Department of Oncology, University of Torino, Via Santena 5bis, 10126 Torino, Italy.
| | - Giorgia Mandili
- Department of Molecular Biotechnology and Health Sciences, Molecular Biotechnology Center, University of Torino Medical School, Via Nizza 52, 10126 Torino, Italy; Center for Experimental Research and Medical Studies (CeRMS), Città della Salute e della Scienza, Ospedale San Giovanni Battista, Via Cherasco 15, 10126 Torino, Italy.
| | - Francesco Novelli
- Department of Molecular Biotechnology and Health Sciences, Molecular Biotechnology Center, University of Torino Medical School, Via Nizza 52, 10126 Torino, Italy; Center for Experimental Research and Medical Studies (CeRMS), Città della Salute e della Scienza, Ospedale San Giovanni Battista, Via Cherasco 15, 10126 Torino, Italy.
| | - Marco Persico
- Department of Pharmacy, University of Napoli 'Federico II', Via D. Montesano 49, 80131 Napoli, Italy.
| | | | - Paolo Arese
- Department of Oncology, University of Torino, Via Santena 5bis, 10126 Torino, Italy.
| | - Evelin Schwarzer
- Department of Oncology, University of Torino, Via Santena 5bis, 10126 Torino, Italy.
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Fernández-Boo S, Villalba A, Cao A. Variable protein profiles in extracellular products of the protistan parasite Perkinsus olseni among regions of the Spanish coast. J Invertebr Pathol 2015; 132:233-241. [DOI: 10.1016/j.jip.2015.11.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Revised: 11/02/2015] [Accepted: 11/06/2015] [Indexed: 10/22/2022]
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Large screen approaches to identify novel malaria vaccine candidates. Vaccine 2015; 33:7496-505. [PMID: 26428458 DOI: 10.1016/j.vaccine.2015.09.059] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Revised: 09/07/2015] [Accepted: 09/15/2015] [Indexed: 11/20/2022]
Abstract
Until recently, malaria vaccine development efforts have focused almost exclusively on a handful of well characterized Plasmodium falciparum antigens. Despite dedicated work by many researchers on different continents spanning more than half a century, a successful malaria vaccine remains elusive. Sequencing of the P. falciparum genome has revealed more than five thousand genes, providing the foundation for systematic approaches to discover candidate vaccine antigens. We are taking advantage of this wealth of information to discover new antigens that may be more effective vaccine targets. Herein, we describe different approaches to large-scale screening of the P. falciparum genome to identify targets of either antibody responses or T cell responses using human specimens collected in Controlled Human Malaria Infections (CHMI) or under conditions of natural exposure in the field. These genome, proteome and transcriptome based approaches offer enormous potential for the development of an efficacious malaria vaccine.
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Bachmann A, Scholz JAM, Janßen M, Klinkert MQ, Tannich E, Bruchhaus I, Petter M. A comparative study of the localization and membrane topology of members of the RIFIN, STEVOR and PfMC-2TM protein families in Plasmodium falciparum-infected erythrocytes. Malar J 2015; 14:274. [PMID: 26173856 PMCID: PMC4502930 DOI: 10.1186/s12936-015-0784-2] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Accepted: 06/27/2015] [Indexed: 12/12/2022] Open
Abstract
Background Variant surface antigens (VSA) exposed on the membrane of Plasmodium falciparum infected erythrocytes mediate immune evasion and are important pathogenicity factors in malaria disease. In addition to the well-studied PfEMP1, the small VSA families RIFIN, STEVOR and PfMC-2TM are assumed to play a role in this process. Methods This study presents a detailed comparative characterization of the localization, membrane topology and extraction profile across the life cycle of various members of these protein families employing confocal microscopy, immunoelectron microscopy and immunoblots. Results The presented data reveal a clear association of variants of the RIFIN, STEVOR and PfMC-2TM proteins with the host cell membrane and topological studies indicate that the semi-conserved N-terminal region of RIFINs and some STEVOR proteins is exposed at the erythrocyte surface. At the Maurer’s clefts, the semi-conserved N-terminal region as well as the variable stretch of RIFINs appears to point to the lumen away from the erythrocyte cytoplasm. These results challenge the previously proposed two transmembrane topology model for the RIFIN and STEVOR protein families and suggest that only one hydrophobic region spans the membrane. In contrast, PfMC-2TM proteins indeed seem to be anchored by two hydrophobic stretches in the host cell membrane exposing just a few, variable amino acids at the surface of the host cell. Conclusion Together, the host cell surface exposure and topology of RIFIN and STEVOR proteins suggests members of these protein families may indeed be involved in immune evasion of the infected erythrocyte, whereas members of the PfMC-2TM family seem to bear different functions in parasite biology. Electronic supplementary material The online version of this article (doi:10.1186/s12936-015-0784-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Anna Bachmann
- Department of Molecular Parasitology, Bernhard Nocht Institute for Tropical Medicine, Bernhard-Nocht-Straße 74, 20359, Hamburg, Germany.
| | - Judith Anna Marie Scholz
- Department of Molecular Parasitology, Bernhard Nocht Institute for Tropical Medicine, Bernhard-Nocht-Straße 74, 20359, Hamburg, Germany.
| | - Marthe Janßen
- Department of Immunology, Bernhard Nocht Institute for Tropical Medicine, Bernhard-Nocht-Straße 74, 20359, Hamburg, Germany. .,CRTD/DFG-Center for Regenerative Therapies Dresden, Technical University Dresden, Fetscherstraße 105, 01307, Dresden, Germany.
| | - Mo-Quen Klinkert
- Department of Molecular Parasitology, Bernhard Nocht Institute for Tropical Medicine, Bernhard-Nocht-Straße 74, 20359, Hamburg, Germany.
| | - Egbert Tannich
- Department of Molecular Parasitology, Bernhard Nocht Institute for Tropical Medicine, Bernhard-Nocht-Straße 74, 20359, Hamburg, Germany.
| | - Iris Bruchhaus
- Department of Molecular Parasitology, Bernhard Nocht Institute for Tropical Medicine, Bernhard-Nocht-Straße 74, 20359, Hamburg, Germany.
| | - Michaela Petter
- Department of Medicine, The Peter Doherty Institute, The University of Melbourne, 792n Elizabeth Street, Melbourne, 3000, VIC, Australia.
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Subudhi AK, Boopathi PA, Pandey I, Kohli R, Karwa R, Middha S, Acharya J, Kochar SK, Kochar DK, Das A. Plasmodium falciparum complicated malaria: Modulation and connectivity between exportome and variant surface antigen gene families. Mol Biochem Parasitol 2015; 201:31-46. [PMID: 26022315 DOI: 10.1016/j.molbiopara.2015.05.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Revised: 05/20/2015] [Accepted: 05/21/2015] [Indexed: 12/27/2022]
Abstract
In temperate and sub-tropical regions of Asia and Latin America, complicated malaria manifested as hepatic dysfunction or renal dysfunction is seen in all age groups. There has been a concerted focus on understanding the patho-physiological and molecular basis of complicated malaria in children, much less is known about it in adults. We report here, the analysis of data from a custom, cross strain microarray (Agilent Platform) using material from adult patient samples, showing hepatic dysfunction or renal failure. These are the most common manifestations seen in adults along with cerebral malaria. The data has been analyzed with reference to variant surface antigens, encoded by the var, rifin and stevor gene families. The differential regulation profiles of key genes (comparison between Plasmodium falciparum complicated and uncomplicated isolates) have been observed. The exportome has been analyzed using similar parameters. Gene ontology term based functional enrichment of differentially regulated genes identified, up-regulated genes statistically enriched (P<0.05) to critical biological processes like generation of precursor metabolite and energy, chromosome organization and electron transport chain. Systems network based functional enrichment of overall differentially regulated genes yielded a similar result. We are reporting here, up-regulation of var group B and C genes whose proteins are predicted to interact with CD36 receptor in the host, the up-regulation of domain cassette 13 (DC13) containing var group A, as also the up-regulation of group A rifins and many of the stevors. This is contrary to most other reports from pediatric patients, with cerebral malaria where the up-regulation of mostly var A group genes have been seen. A protein-protein interaction based network has been created and analysis performed. This co-expression and text mining based network has shown overall connectivity between the variant surface antigens (VSA) and the exportome. The up-regulation of var group B and C genes encoding PfEMP1 with different domain architecture would be important for deciding strategies for disease prevention.
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Affiliation(s)
- Amit Kumar Subudhi
- Department of Biological Sciences, Birla Institute of Technology and Science (BITS), Pilani, Rajasthan, India.
| | - P A Boopathi
- Department of Biological Sciences, Birla Institute of Technology and Science (BITS), Pilani, Rajasthan, India.
| | - Isha Pandey
- Department of Biological Sciences, Birla Institute of Technology and Science (BITS), Pilani, Rajasthan, India.
| | - Ramandeep Kohli
- Department of Biological Sciences, Birla Institute of Technology and Science (BITS), Pilani, Rajasthan, India.
| | - Rohan Karwa
- Department of Biological Sciences, Birla Institute of Technology and Science (BITS), Pilani, Rajasthan, India.
| | - Sheetal Middha
- Department of Medicine, S.P. Medical College, Bikaner, Rajasthan, India.
| | - Jyoti Acharya
- Department of Medicine, S.P. Medical College, Bikaner, Rajasthan, India.
| | - Sanjay K Kochar
- Department of Medicine, S.P. Medical College, Bikaner, Rajasthan, India.
| | - Dhanpat K Kochar
- Rajasthan University of Health Sciences, Jaipur, Rajasthan, India.
| | - Ashis Das
- Department of Biological Sciences, Birla Institute of Technology and Science (BITS), Pilani, Rajasthan, India.
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Mbengue A, Vialla E, Berry L, Fall G, Audiger N, Demettre-Verceil E, Boteller D, Braun-Breton C. New Export Pathway inPlasmodium falciparum-Infected Erythrocytes: Role of the Parasite Group II Chaperonin, PfTRiC. Traffic 2015; 16:461-75. [DOI: 10.1111/tra.12266] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2013] [Revised: 01/20/2015] [Accepted: 01/21/2015] [Indexed: 11/28/2022]
Affiliation(s)
- Alassane Mbengue
- University Montpellier II; CNRS UMR 5235, University Montpellier I; Dynamique des Interactions Membranaires Normales et Pathologiques 34095 Montpellier Cedex 5 France
| | - Emilie Vialla
- University Montpellier II; CNRS UMR 5235, University Montpellier I; Dynamique des Interactions Membranaires Normales et Pathologiques 34095 Montpellier Cedex 5 France
| | - Laurence Berry
- University Montpellier II; CNRS UMR 5235, University Montpellier I; Dynamique des Interactions Membranaires Normales et Pathologiques 34095 Montpellier Cedex 5 France
| | - Gamou Fall
- University Montpellier II; CNRS UMR 5235, University Montpellier I; Dynamique des Interactions Membranaires Normales et Pathologiques 34095 Montpellier Cedex 5 France
| | - Nicolas Audiger
- University Montpellier II; CNRS UMR 5235, University Montpellier I; Dynamique des Interactions Membranaires Normales et Pathologiques 34095 Montpellier Cedex 5 France
| | - Edith Demettre-Verceil
- Plate-forme de Protéomique Fonctionnelle - FPP; UMS CNRS 3426 - US 009 INSERM - UMI - UMII, IGF; 141 rue de la Cardonille 34094 Montpellier Cedex 5 France
| | - David Boteller
- University Montpellier II; CNRS UMR 5235, University Montpellier I; Dynamique des Interactions Membranaires Normales et Pathologiques 34095 Montpellier Cedex 5 France
| | - Catherine Braun-Breton
- University Montpellier II; CNRS UMR 5235, University Montpellier I; Dynamique des Interactions Membranaires Normales et Pathologiques 34095 Montpellier Cedex 5 France
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Dietz O, Rusch S, Brand F, Mundwiler-Pachlatko E, Gaida A, Voss T, Beck HP. Characterization of the small exported Plasmodium falciparum membrane protein SEMP1. PLoS One 2014; 9:e103272. [PMID: 25062022 PMCID: PMC4111544 DOI: 10.1371/journal.pone.0103272] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Accepted: 06/26/2014] [Indexed: 12/03/2022] Open
Abstract
Survival and virulence of the human malaria parasite Plasmodium falciparum during the blood stage of infection critically depend on extensive host cell refurbishments mediated through export of numerous parasite proteins into the host cell. The parasite-derived membranous structures called Maurer's clefts (MC) play an important role in protein trafficking from the parasite to the red blood cell membrane. However, their specific function has yet to be determined. We identified and characterized a new MC membrane protein, termed small exported membrane protein 1 (SEMP1). Upon invasion it is exported into the RBC cytosol where it inserts into the MCs before it is partly translocated to the RBC membrane. Using conventional and conditional loss-of-function approaches we showed that SEMP1 is not essential for parasite survival, gametocytogenesis, or PfEMP1 export under culture conditions. Co-IP experiments identified several potential interaction partners, including REX1 and other membrane-associated proteins that were confirmed to co-localize with SEMP1 at MCs. Transcriptome analysis further showed that expression of a number of exported parasite proteins was up-regulated in SEMP1-depleted parasites. By using Co-IP and transcriptome analysis for functional characterization of an exported parasite protein we provide a new starting point for further detailed dissection and characterisation of MC-associated protein complexes.
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Affiliation(s)
- Olivier Dietz
- Swiss Tropical and Public Health Institute, Department of Medical Parasitology and Infection Biology, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Sebastian Rusch
- Swiss Tropical and Public Health Institute, Department of Medical Parasitology and Infection Biology, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Françoise Brand
- Swiss Tropical and Public Health Institute, Department of Medical Parasitology and Infection Biology, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Esther Mundwiler-Pachlatko
- Swiss Tropical and Public Health Institute, Department of Medical Parasitology and Infection Biology, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Annette Gaida
- Swiss Tropical and Public Health Institute, Department of Medical Parasitology and Infection Biology, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Till Voss
- Swiss Tropical and Public Health Institute, Department of Medical Parasitology and Infection Biology, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Hans-Peter Beck
- Swiss Tropical and Public Health Institute, Department of Medical Parasitology and Infection Biology, Basel, Switzerland
- University of Basel, Basel, Switzerland
- * E-mail:
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Abstract
SUMMARYPlasmodium falciparumdisplays a large and remarkable variety of heat shock protein 40 family members (PfHsp40s). The majority of the PfHsp40s are poorly characterized, and although the functions of some of them have been suggested, their exact mechanism of action is still elusive and their interacting partners and client proteins are unknown. TheP. falciparumheat shock protein 70 family members (PfHsp70s) have been more extensively characterized than the PfHsp40s, with certain members shown to function as molecular chaperones. However, little is known about the PfHsp70-PfHsp40 chaperone partnerships. There is mounting evidence that these chaperones are important not only in protein homoeostasis and cytoprotection, but also in protein trafficking across the parasitophorous vacuole (PV) and into the infected erythrocyte. We propose that certain members of these chaperone families work together to maintain exported proteins in an unfolded state until they reach their final destination. In this review, we critically evaluate what is known and not known about PfHsp40s and PfHsp70s.
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Abstract
Plasmodium falciparum, the causative agent of malaria, completely remodels the infected human erythrocyte to acquire nutrients and to evade the immune system. For this process, the parasite exports more than 10% of all its proteins into the host cell cytosol, including the major virulence factor PfEMP1 (P. falciparum erythrocyte surface protein 1). This unusual protein trafficking system involves long-known parasite-derived membranous structures in the host cell cytosol, called Maurer's clefts. However, the genesis, role, and function of Maurer's clefts remain elusive. Similarly unclear is how proteins are sorted and how they are transported to and from these structures. Recent years have seen a large increase of knowledge but, as yet, no functional model has been established. In this perspective we review the most important findings and conclude with potential possibilities to shed light into the enigma of Maurer's clefts. Understanding the mechanism and function of these structures, as well as their involvement in protein export in P. falciparum, might lead to innovative control strategies and might give us a handle with which to help to eliminate this deadly parasite.
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Malaria proteomics: insights into the parasite-host interactions in the pathogenic space. J Proteomics 2013; 97:107-25. [PMID: 24140976 DOI: 10.1016/j.jprot.2013.10.011] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2013] [Revised: 06/23/2013] [Accepted: 10/08/2013] [Indexed: 11/23/2022]
Abstract
Proteomics is improving malaria research by providing global information on relevant protein sets from the parasite and the host in connection with its cellular structures and specific functions. In the last decade, reports have described biologically significant elements in the proteome of Plasmodium, which are selectively targeted and quantified, allowing for sensitive and high-throughput comparisons. The identification of molecules by which the parasite and the host react during the malaria infection is crucial to the understanding of the underlying pathogenic mechanisms. Hence, proteomics is playing a major role by defining the elements within the pathogenic space between both organisms that change across the parasite life cycle in association with the host transformation and response. Proteomics has identified post-translational modifications in the parasite and the host that are discussed in terms of functional interactions in malaria parasitism. Furthermore, the contribution of proteomics to the investigation of immunogens for potential vaccine candidates is summarized. The malaria-specific technological advances in proteomics are particularly suited now for identifying host-parasite interactions that could lead to promising targets for therapy, diagnosis or prevention. In this review, we examine the knowledge gained on the biology, pathogenesis, immunity and diagnosis of Plasmodium infection from recent proteomic studies. This article is part of a Special Issue entitled: Trends in Microbial Proteomics.
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Yam XY, Birago C, Fratini F, Di Girolamo F, Raggi C, Sargiacomo M, Bachi A, Berry L, Fall G, Currà C, Pizzi E, Breton CB, Ponzi M. Proteomic analysis of detergent-resistant membrane microdomains in trophozoite blood stage of the human malaria parasite Plasmodium falciparum. Mol Cell Proteomics 2013; 12:3948-61. [PMID: 24045696 DOI: 10.1074/mcp.m113.029272] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Intracellular pathogens contribute to a significant proportion of infectious diseases worldwide. The successful strategy of evading the immune system by hiding inside host cells is common to all the microorganism classes, which exploit membrane microdomains, enriched in cholesterol and sphingolipids, to invade and colonize the host cell. These assemblies, with distinct biochemical properties, can be isolated by means of flotation in sucrose density gradient centrifugation because they are insoluble in nonionic detergents at low temperature. We analyzed the protein and lipid contents of detergent-resistant membranes from erythrocytes infected by Plasmodium falciparum, the most deadly human malaria parasite. Proteins associated with membrane microdomains of trophic parasite blood stages (trophozoites) include an abundance of chaperones, molecules involved in vesicular trafficking, and enzymes implicated in host hemoglobin degradation. About 60% of the identified proteins contain a predicted localization signal suggesting a role of membrane microdomains in protein sorting/trafficking. To validate our proteomic data, we raised antibodies against six Plasmodium proteins not characterized previously. All the selected candidates were recovered in floating low-density fractions after density gradient centrifugation. The analyzed proteins localized either to internal organelles, such as the mitochondrion and the endoplasmic reticulum, or to exported membrane structures, the parasitophorous vacuole membrane and Maurer's clefts, implicated in targeting parasite proteins to the host erythrocyte cytosol or surface. The relative abundance of cholesterol and phospholipid species varies in gradient fractions containing detergent-resistant membranes, suggesting heterogeneity in the lipid composition of the isolated microdomain population. This study is the first report showing the presence of cholesterol-rich microdomains with distinct properties and subcellular localization in trophic stages of Plasmodium falciparum.
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Affiliation(s)
- Xue Yan Yam
- University Montpellier II, CNRS UMR 5235, 34095 Montpellier, Cedex 5, France
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Mbengue A, Audiger N, Vialla E, Dubremetz JF, Braun-Breton C. NovelPlasmodium falciparum Maurer's clefts protein families implicated in the release of infectious merozoites. Mol Microbiol 2013; 88:425-42. [DOI: 10.1111/mmi.12193] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/27/2013] [Indexed: 11/30/2022]
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Deponte M, Hoppe HC, Lee MC, Maier AG, Richard D, Rug M, Spielmann T, Przyborski JM. Wherever I may roam: Protein and membrane trafficking in P. falciparum-infected red blood cells. Mol Biochem Parasitol 2012; 186:95-116. [DOI: 10.1016/j.molbiopara.2012.09.007] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2012] [Revised: 09/21/2012] [Accepted: 09/24/2012] [Indexed: 11/27/2022]
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Oehring SC, Woodcroft BJ, Moes S, Wetzel J, Dietz O, Pulfer A, Dekiwadia C, Maeser P, Flueck C, Witmer K, Brancucci NMB, Niederwieser I, Jenoe P, Ralph SA, Voss TS. Organellar proteomics reveals hundreds of novel nuclear proteins in the malaria parasite Plasmodium falciparum. Genome Biol 2012. [PMID: 23181666 PMCID: PMC4053738 DOI: 10.1186/gb-2012-13-11-r108] [Citation(s) in RCA: 116] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
BACKGROUND The post-genomic era of malaria research provided unprecedented insights into the biology of Plasmodium parasites. Due to the large evolutionary distance to model eukaryotes, however, we lack a profound understanding of many processes in Plasmodium biology. One example is the cell nucleus, which controls the parasite genome in a development- and cell cycle-specific manner through mostly unknown mechanisms. To study this important organelle in detail, we conducted an integrative analysis of the P. falciparum nuclear proteome. RESULTS We combined high accuracy mass spectrometry and bioinformatic approaches to present for the first time an experimentally determined core nuclear proteome for P. falciparum. Besides a large number of factors implicated in known nuclear processes, one-third of all detected proteins carry no functional annotation, including many phylum- or genus-specific factors. Importantly, extensive experimental validation using 30 transgenic cell lines confirmed the high specificity of this inventory, and revealed distinct nuclear localization patterns of hitherto uncharacterized proteins. Further, our detailed analysis identified novel protein domains potentially implicated in gene transcription pathways, and sheds important new light on nuclear compartments and processes including regulatory complexes, the nucleolus, nuclear pores, and nuclear import pathways. CONCLUSION Our study provides comprehensive new insight into the biology of the Plasmodium nucleus and will serve as an important platform for dissecting general and parasite-specific nuclear processes in malaria parasites. Moreover, as the first nuclear proteome characterized in any protist organism, it will provide an important resource for studying evolutionary aspects of nuclear biology.
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Wang B, Lu F, Cheng Y, Li J, Ito D, Sattabongkot J, Tsuboi T, Han ET. Identification and characterization of the Plasmodium falciparum RhopH2 ortholog in Plasmodium vivax. Parasitol Res 2012; 112:585-93. [PMID: 23097184 DOI: 10.1007/s00436-012-3170-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2012] [Accepted: 10/08/2012] [Indexed: 11/28/2022]
Abstract
Plasmodium vivax is one of the most important human malaria species that is geographically widely endemic and potentially affects a larger number of people than its more notorious cousin, Plasmodium falciparum. During invasion of red blood cells, the parasite requires the intervention of high molecular weight complex rhoptry proteins (RhopH) that are also essential for cytoadherence. PfRhopH2, a member of the RhopH multigene family, has been characterized as being crucial during P. falciparum infection. This study describes identifying and characterizing the pfrhoph2 orthologous gene in P. vivax (hereinafter named pvrhoph2). The PvRhopH2 is a 1,369-amino acid polypeptide encoded by PVX_099930 gene, for which orthologous genes have been identified in other Plasmodium species by bioinformatic approaches. Both P. falciparum and P. vivax genes contain nine introns, and there is a high degree of similarity between the deduced amino acid sequences of the two proteins. Moreover, PvRhopH2 contains a signal peptide at its N-terminus and 12 cysteines predominantly in its C-terminal half. PvRhopH2 is localized in one of the apical organelles of the merozoite, the rhoptry, and the localization pattern is similar to that of PfRhopH2 in P. falciparum. The recombinant PvRhopH2 protein is recognized by serum antibodies of patients naturally exposed to P. vivax, suggesting that PvRhopH2 is immunogenic in humans.
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Affiliation(s)
- Bo Wang
- Department of Medical Environmental Biology and Tropical Medicine, Kangwon National University School of Medicine, Hyoja2-dong, Chuncheon, Gangwon-do 200-701, Republic of Korea
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Determination of protein subcellular localization in apicomplexan parasites. Trends Parasitol 2012; 28:546-54. [PMID: 22995720 DOI: 10.1016/j.pt.2012.08.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2012] [Revised: 08/22/2012] [Accepted: 08/24/2012] [Indexed: 11/20/2022]
Abstract
Parasites from the phylum Apicomplexa include causative agents of serious diseases including malaria (Plasmodium spp.) and toxoplasmosis (Toxoplasma gondii). Apicomplexan parasites infect thousands of types of animal cells and send their proteins to an array of compartments within their own cell, as well as exporting proteins into and beyond their host cell. Ascertaining destinations to which individual proteins are delivered allows researchers to better understand parasite biology and to identify potential targets for therapeutic interventions. Our toolkit for establishing subcellular locations of apicomplexan proteins is becoming more extensive and specialized, and here we review developments in this technology.
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