51
|
Drew DR, Sanders PR, Weiss G, Gilson PR, Crabb BS, Beeson JG. Functional Conservation of the AMA1 Host-Cell Invasion Ligand Between P. falciparum and P. vivax: A Novel Platform to Accelerate Vaccine and Drug Development. J Infect Dis 2019; 217:498-507. [PMID: 29165651 DOI: 10.1093/infdis/jix583] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Accepted: 11/17/2017] [Indexed: 01/20/2023] Open
Abstract
Plasmodium vivax and P. falciparum malaria species have diverged significantly in receptor-ligand interactions and host-cell invasion. One protein common to both is the merozoite invasion ligand AMA1. While the general structure of AMA1 is similar between species, their sequences are divergent. Surprisingly, it was possible to genetically replace PfAMA1 with PvAMA1 in P. falciparum parasites. PvAMA1 complemented PfAMA1 function and supported invasion of erythrocytes by P. falciparum. Genetically modified P. falciparum expressing PvAMA1 evaded the invasion inhibitory effects of antibodies to PfAMA1, demonstrating species specificity of functional antibodies. We generated antibodies to recombinant PvAMA1 that effectively inhibited invasion, confirming the function of PvAMA1 in genetically modified parasites. Results indicate significant molecular flexibility in AMA1 enabling conserved function despite substantial sequence divergence across species. This provides powerful new tools to quantify the inhibitory activities of antibodies or drugs targeting PvAMA1, opening new opportunities for vaccine and therapeutic development against P. vivax.
Collapse
Affiliation(s)
| | | | | | | | - Brendan S Crabb
- Burnet Institute, Melbourne, Australia.,Department of Medicine, University of Melbourne, Victoria, Australia.,Department of Microbiology and Immunology, University of Melbourne, Victoria, Australia
| | - James G Beeson
- Burnet Institute, Melbourne, Australia.,Department of Medicine, University of Melbourne, Victoria, Australia.,Department of Microbiology and Immunology, University of Melbourne, Victoria, Australia.,Central Clinical School and Department of Microbiology, Monash University, Victoria, Australia
| |
Collapse
|
52
|
Akter M, Drinkwater N, Devine SM, Drew SC, Krishnarjuna B, Debono CO, Wang G, Scanlon MJ, Scammells PJ, McGowan S, MacRaild CA, Norton RS. Identification of the Binding Site of Apical Membrane Antigen 1 (AMA1) Inhibitors Using a Paramagnetic Probe. ChemMedChem 2019; 14:603-612. [PMID: 30653832 DOI: 10.1002/cmdc.201800802] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Indexed: 11/08/2022]
Abstract
Apical membrane antigen 1 (AMA1) is essential for the invasion of host cells by malaria parasites. Several small-molecule ligands have been shown to bind to a conserved hydrophobic cleft in Plasmodium falciparum AMA1. However, a lack of detailed structural information on the binding pose of these molecules has hindered their further optimisation as inhibitors. We have developed a spin-labelled peptide based on RON2, the native binding partner of AMA1, to probe the binding sites of compounds on PfAMA1. The crystal structure of this peptide bound to PfAMA1 shows that it binds at one end of the hydrophobic groove, leaving much of the binding site unoccupied and allowing fragment hits to bind without interference. In paramagnetic relaxation enhancement (PRE)-based NMR screening, the 1 H relaxation rates of compounds binding close to the probe were enhanced. Compounds experienced different degrees of PRE as a result of their different orientations relative to the spin label while bound to AMA1. Thus, PRE-derived distance constraints can be used to identify binding sites and guide further hit optimisation.
Collapse
Affiliation(s)
- Mansura Akter
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, 3052, Australia
| | - Nyssa Drinkwater
- Biomedicine Discovery Institute, Department of Microbiology, Monash University, Wellington Road, Clayton, Victoria, 3800, Australia
| | - Shane M Devine
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, 3052, Australia
| | - Simon C Drew
- Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Melbourne, Victoria, 3010, Australia
| | - Bankala Krishnarjuna
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, 3052, Australia
| | - Cael O Debono
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, 3052, Australia
| | - Geqing Wang
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, 3052, Australia
| | - Martin J Scanlon
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, 3052, Australia
| | - Peter J Scammells
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, 3052, Australia
| | - Sheena McGowan
- Biomedicine Discovery Institute, Department of Microbiology, Monash University, Wellington Road, Clayton, Victoria, 3800, Australia
| | - Christopher A MacRaild
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, 3052, Australia
| | - Raymond S Norton
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, 3052, Australia
| |
Collapse
|
53
|
Reverse immunodynamics: a new method for identifying targets of protective immunity. Sci Rep 2019; 9:2164. [PMID: 30770839 PMCID: PMC6377634 DOI: 10.1038/s41598-018-37288-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Accepted: 11/20/2018] [Indexed: 12/21/2022] Open
Abstract
Despite a dramatic increase in our ability to catalogue variation among pathogen genomes, we have made far fewer advances in using this information to identify targets of protective immunity. Epidemiological models predict that strong immune selection can cause antigenic variants to structure into genetically discordant sets of antigenic types (e.g. serotypes). A corollary of this theory is that targets of immunity may be identified by searching for non-overlapping associations of amino acids among co-circulating antigenic variants. We propose a novel population genetics methodology that combines such predictions with phylogenetic analyses to identify genetic loci (epitopes) under strong immune selection. We apply this concept to the AMA-1 protein of the malaria parasite Plasmodium falciparum and find evidence of epitopes among certain regions of low variability which could render them ideal vaccine candidates. The proposed method can be applied to a myriad of multi-strain pathogens for which vast amounts of genetic data has been collected in recent years.
Collapse
|
54
|
Salgado-Mejias P, Alves FL, Françoso KS, Riske KA, Silva ER, Miranda A, Soares IS. Structure of Rhoptry Neck Protein 2 is essential for the interaction in vitro with Apical Membrane Antigen 1 in Plasmodium vivax. Malar J 2019; 18:25. [PMID: 30683104 PMCID: PMC6347818 DOI: 10.1186/s12936-019-2649-6] [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: 10/01/2018] [Accepted: 01/13/2019] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND In several Apicomplexa, the formation of moving junctions (MJs) at the interface between the external membranes of the invading parasite and the host cell is essential for the process of parasite invasion. In Plasmodium falciparum and Toxoplasma gondii, the MJ is composed of the Apical Membrane Antigen 1 (AMA1) and Rhoptry Neck Proteins (RONs) complex; specifically, AMA1 interacts with RON2 during host cell invasion. METHODS Recombinant proteins based on Plasmodium vivax RON2 (A2033-P2100) and its synthetic peptide fragments, one cyclic and one linear, based on PvRON2 (D2035-T2074) were generated and used to evaluate the interaction with P. vivax AMA1 (PvAMA1) by the far western blot, surface plasmon resonance (SPR), and isothermal titration microcalorimetry (ITC) methods. The structural studies of peptides were performed by circular dichroism, and the structural analysis of the complex of PvAMA1 with peptides based on PvRON2 (D2035-T2074) was conducted with small-angle X-ray scattering (SAXS). RESULTS Surface plasmon resonance (KD = 23.91 ± 2.078 μmol/L) and ITC (K = 3 × 105 mol/L) studies conclusively showed an interaction between the cyclic peptide based on PvRON2 and PvAMA1-His6. In contrast, the linear peptide and recombinant PvRON2 (GST fusion protein) did not show an interaction with PvAMA1. However, the interaction among recombinant proteins PvRON2.2 and PvAMA1-His6 was possible to show by far western blot. CONCLUSIONS The results show that the PvRON2 structure, particularly the S-S bond between C2051 and C2063, is determinant for the existence of the interaction between PvAMA1 and PvRON2.
Collapse
Affiliation(s)
- Perla Salgado-Mejias
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, SP, Brazil.,Department of Chemical Sciences and Natural Resources, Faculty of Engineering and Science, University of La Frontera, Temuco, Chile
| | - Flavio L Alves
- Departamento de Biofísica, Universidade Federal de São Paulo, São Paulo, SP, Brazil
| | - Kátia S Françoso
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Karin A Riske
- Departamento de Biofísica, Universidade Federal de São Paulo, São Paulo, SP, Brazil
| | - Emerson R Silva
- Departamento de Biofísica, Universidade Federal de São Paulo, São Paulo, SP, Brazil
| | - Antonio Miranda
- Departamento de Biofísica, Universidade Federal de São Paulo, São Paulo, SP, Brazil
| | - Irene S Soares
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, SP, Brazil.
| |
Collapse
|
55
|
Ishino T, Murata E, Tokunaga N, Baba M, Tachibana M, Thongkukiatkul A, Tsuboi T, Torii M. Rhoptry neck protein 2 expressed in Plasmodium sporozoites plays a crucial role during invasion of mosquito salivary glands. Cell Microbiol 2018; 21:e12964. [PMID: 30307699 PMCID: PMC6587811 DOI: 10.1111/cmi.12964] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 09/28/2018] [Accepted: 10/05/2018] [Indexed: 01/03/2023]
Abstract
Malaria parasite transmission to humans is initiated by the inoculation of Plasmodium sporozoites into the skin by mosquitoes. Sporozoites develop within mosquito midgut oocysts, first invade the salivary glands of mosquitoes, and finally infect hepatocytes in mammals. The apical structure of sporozoites is conserved with the infective forms of other apicomplexan parasites that have secretory organelles, such as rhoptries and micronemes. Because some rhoptry proteins are crucial for Plasmodium merozoite infection of erythrocytes, we examined the roles of rhoptry proteins in sporozoites. Here, we demonstrate that rhoptry neck protein 2 (RON2) is also localized to rhoptries in sporozoites. To elucidate RON2 function in sporozoites, we applied a promoter swapping strategy to restrict ron2 transcription to the intraerythrocytic stage in the rodent malaria parasite, Plasmodium berghei. Ron2 knockdown sporozoites were severely impaired in their ability to invade salivary glands, via decreasing the attachment capacity to the substrate. This is the first rhoptry protein demonstrated to be involved in salivary gland invasion. In addition, ron2 knockdown sporozoites showed less infectivity to hepatocytes, possibly due to decreased attachment/gliding ability, indicating that parts of the parasite invasion machinery are conserved, but their contribution might differ among infective forms. Our sporozoite stage‐specific knockdown system will help to facilitate understanding the comprehensive molecular mechanisms of parasite invasion of target cells.
Collapse
Affiliation(s)
- Tomoko Ishino
- Division of Molecular Parasitology, Proteo-Science Center, Ehime University, Toon, Japan
| | - Eri Murata
- Division of Molecular Parasitology, Proteo-Science Center, Ehime University, Toon, Japan.,Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Japan
| | - Naohito Tokunaga
- Division of Molecular Parasitology, Proteo-Science Center, Ehime University, Toon, Japan
| | - Minami Baba
- Division of Molecular Parasitology, Proteo-Science Center, Ehime University, Toon, Japan
| | - Mayumi Tachibana
- Division of Molecular Parasitology, Proteo-Science Center, Ehime University, Toon, Japan
| | | | - Takafumi Tsuboi
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Japan
| | - Motomi Torii
- Division of Molecular Parasitology, Proteo-Science Center, Ehime University, Toon, Japan
| |
Collapse
|
56
|
Quintana MDP, Ch’ng JH, Zandian A, Imam M, Hultenby K, Theisen M, Nilsson P, Qundos U, Moll K, Chan S, Wahlgren M. SURGE complex of Plasmodium falciparum in the rhoptry-neck (SURFIN4.2-RON4-GLURP) contributes to merozoite invasion. PLoS One 2018; 13:e0201669. [PMID: 30092030 PMCID: PMC6084945 DOI: 10.1371/journal.pone.0201669] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Accepted: 07/19/2018] [Indexed: 12/25/2022] Open
Abstract
Plasmodium falciparum invasion into red blood cells (RBCs) is a complex process engaging proteins on the merozoite surface and those contained and sequentially released from the apical organelles (micronemes and rhoptries). Fundamental to invasion is the formation of a moving junction (MJ), a region of close apposition of the merozoite and the RBC plasma membranes, through which the merozoite draws itself before settling into a newly formed parasitophorous vacuole (PV). SURFIN4.2 was identified at the surface of the parasitized RBCs (pRBCs) but was also found apically associated with the merozoite. Using antibodies against the N-terminus of the protein we show the presence of SURFIN4.2 in the neck of the rhoptries, its secretion into the PV and shedding into the culture supernatant upon schizont rupture. Using immunoprecipitation followed by mass spectrometry we describe here a novel protein complex we have named SURGE where SURFIN4.2 forms interacts with the rhoptry neck protein 4 (RON4) and the Glutamate Rich Protein (GLURP). The N-terminal cysteine-rich-domain (CRD) of SURFIN4.2 mediates binding to the RBC membrane and its interaction with RON4 suggests its involvement in the contact between the merozoite apex and the RBC at the MJ. Supporting this suggestion, we also found that polyclonal antibodies to the extracellular domain (including the CRD) of SURFIN4.2 partially inhibit merozoite invasion. We propose that the formation of the SURGE complex participates in the establishment of parasite infection within the PV and the RBCs.
Collapse
Affiliation(s)
- Maria del Pilar Quintana
- Department of Microbiology, Tumor and Cell Biology (MTC), Biomedicum, Karolinska Institutet, Stockholm, Sweden
| | - Jun-Hong Ch’ng
- Department of Microbiology, Tumor and Cell Biology (MTC), Biomedicum, Karolinska Institutet, Stockholm, Sweden
- Department of Microbiology and Immunology, National University of Singapore, Singapore, Singapore
| | - Arash Zandian
- Affinity Proteomics, Science for Life Laboratory, School of Biotechnology, KTH-Royal Institutet of Technology, Stockholm, Sweden
| | - Maryam Imam
- Department of Microbiology, Tumor and Cell Biology (MTC), Biomedicum, Karolinska Institutet, Stockholm, Sweden
| | - Kjell Hultenby
- Division of Clinical Research Centre, Department of Laboratory Medicine, Karolinska Institutet, Huddinge, Sweden
| | - Michael Theisen
- Department for Congenital Disorders, Statens Serum Institut, Copenhagen, Denmark
- Centre for Medical Parasitology, Department of International Health, Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark
| | - Peter Nilsson
- Affinity Proteomics, Science for Life Laboratory, School of Biotechnology, KTH-Royal Institutet of Technology, Stockholm, Sweden
| | - Ulrika Qundos
- Affinity Proteomics, Science for Life Laboratory, School of Biotechnology, KTH-Royal Institutet of Technology, Stockholm, Sweden
| | - Kirsten Moll
- Department of Microbiology, Tumor and Cell Biology (MTC), Biomedicum, Karolinska Institutet, Stockholm, Sweden
| | - Sherwin Chan
- Department of Microbiology, Tumor and Cell Biology (MTC), Biomedicum, Karolinska Institutet, Stockholm, Sweden
| | - Mats Wahlgren
- Department of Microbiology, Tumor and Cell Biology (MTC), Biomedicum, Karolinska Institutet, Stockholm, Sweden
| |
Collapse
|
57
|
Tijani MK, Reddy SB, Langer C, Beeson JG, Wahlgren M, Nwuba RI, Persson KEM. Factors influencing the induction of high affinity antibodies to Plasmodium falciparum merozoite antigens and how affinity changes over time. Sci Rep 2018; 8:9026. [PMID: 29899351 PMCID: PMC5998021 DOI: 10.1038/s41598-018-27361-w] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Accepted: 06/01/2018] [Indexed: 01/16/2023] Open
Abstract
Understanding the functional characteristics of naturally acquired antibodies against P. falciparum merozoite antigens is crucial for determining the protective functions of antibodies. Affinity (measured as kd) of naturally acquired antibodies against two key targets of acquired immunity, EBA175 and PfRh2, was determined using Surface Plasmon Resonance (SPR) in a longitudinal survey in Nigeria. A majority of the participants, 79% and 67%, maintained stable antibody affinities to EBA175 and PfRh2, respectively, over time. In about 10% of the individuals, there was a reciprocal interaction with a reduction over time in antibody affinity for PfRh2 and an increase for EBA175. In general, PfRh2 elicited antibodies with higher affinity compared to EBA175. Individuals with higher exposure to malaria produced antibodies with higher affinity to both antigens. Younger individuals (5–15 years) produced comparable or higher affinity antibodies than adults (>15 years) against EBA175, but not for PfRh2. Correlation between total IgG (ELISA) and affinity varied between individuals, but PfRh2 elicited antibodies with a higher correlation in a majority of the participants. There was also a correlation between antibody inhibition of erythrocyte invasion by merozoites and PfRh2 affinity. This work gives new insights into the generation and maintenance of antibody affinity over time.
Collapse
Affiliation(s)
- Muyideen K Tijani
- Cellular Parasitology Programme, Cell Biology and Genetics Unit, Department of Zoology, University of Ibadan, Ibadan, Nigeria.,Department of Microbiology, Tumor and Cell Biology (MTC), Karolinska Institutet, Stockholm, Sweden
| | - Sreenivasulu B Reddy
- Department of Microbiology, Tumor and Cell Biology (MTC), Karolinska Institutet, Stockholm, Sweden
| | - Christine Langer
- The Macfarlane Burnet Institute for Medical Research and Public Health, Melbourne, Victoria, Australia
| | - James G Beeson
- The Macfarlane Burnet Institute for Medical Research and Public Health, Melbourne, Victoria, Australia
| | - Mats Wahlgren
- Department of Microbiology, Tumor and Cell Biology (MTC), Karolinska Institutet, Stockholm, Sweden
| | - Roseangela I Nwuba
- Cellular Parasitology Programme, Cell Biology and Genetics Unit, Department of Zoology, University of Ibadan, Ibadan, Nigeria
| | - Kristina E M Persson
- Department of Microbiology, Tumor and Cell Biology (MTC), Karolinska Institutet, Stockholm, Sweden. .,Department of Laboratory Medicine, Lund University, Skåne University Hospital, Lund, Sweden.
| |
Collapse
|
58
|
Guy AJ, Irani V, Richards JS, Ramsland PA. Structural patterns of selection and diversity for Plasmodium vivax antigens DBP and AMA1. Malar J 2018; 17:183. [PMID: 29720179 PMCID: PMC5930944 DOI: 10.1186/s12936-018-2324-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Accepted: 04/18/2018] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND Plasmodium vivax is a significant contributor to the global malaria burden, and a vaccine targeting vivax malaria is urgently needed. An understanding of the targets of functional immune responses during the course of natural infection will aid in the development of a vaccine. Antibodies play a key role in this process, with responses against particular epitopes leading to immune selection pressure on these epitopes. A number of techniques exist to estimate levels of immune selection pressure on particular epitopes, with a sliding window analysis often used to determine particular regions likely to be under immune pressure. However, such analysis neglects protein three-dimensional structural information. With this in mind, a newly developed tool, BioStructMap, was applied to two key antigens from Plasmodium vivax: PvAMA1 and PvDBP Region II. This tool incorporates structural information into tests of selection pressure. RESULTS Sequences from a number of populations were analysed, examining spatially-derived nucleotide diversity and Tajima's D over protein structures for PvAMA1 and PvDBP. Structural patterns of nucleotide diversity were similar across all populations examined, with Domain I of PvAMA1 having the highest nucleotide diversity and displaying significant signatures of immune selection pressure (Tajima's D > 0). Nucleotide diversity for PvDBP was highest bordering the dimerization and DARC-binding interface, although there was less evidence of immune selection pressure on PvDBP compared with PvAMA1. This study supports previous work that has identified Domain I as the main target of immune-mediated selection pressure for PvAMA1, and also supports studies that have identified functional epitopes within PvDBP Region II. CONCLUSIONS The BioStructMap tool was applied to leading vaccine candidates from P. vivax, to examine structural patterns of selection and diversity across a number of geographic populations. There were striking similarities in structural patterns of diversity across multiple populations. Furthermore, whilst regions of high diversity tended to surround conserved binding interfaces, a number of protein regions with very low diversity were also identified, and these may be useful targets for further vaccine development, given previous evidence of functional antibody responses against these regions.
Collapse
Affiliation(s)
- Andrew J Guy
- Life Sciences, Burnet Institute, 85 Commercial Road, Melbourne, VIC, 3004, Australia.,Department of Immunology, Monash University, Melbourne, Australia
| | - Vashti Irani
- Life Sciences, Burnet Institute, 85 Commercial Road, Melbourne, VIC, 3004, Australia.,Department of Medicine, University of Melbourne, Melbourne, Australia
| | - Jack S Richards
- Life Sciences, Burnet Institute, 85 Commercial Road, Melbourne, VIC, 3004, Australia. .,Department of Medicine, University of Melbourne, Melbourne, Australia. .,Department of Infectious Diseases, Monash University, Melbourne, Australia. .,Victorian Infectious Diseases Service, Royal Melbourne Hospital, Melbourne, Australia.
| | - Paul A Ramsland
- Life Sciences, Burnet Institute, 85 Commercial Road, Melbourne, VIC, 3004, Australia. .,Department of Immunology, Monash University, Melbourne, Australia. .,School of Science, RMIT University, Plenty Road, Bundoora, VIC, 3083, Australia. .,Department of Surgery Austin Health, University of Melbourne, Heidelberg, Australia.
| |
Collapse
|
59
|
Hallée S, Counihan NA, Matthews K, Koning‐Ward TF, Richard D. The malaria parasite
Plasmodium falciparum
Sortilin is essential for merozoite formation and apical complex biogenesis. Cell Microbiol 2018; 20:e12844. [DOI: 10.1111/cmi.12844] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Revised: 02/22/2018] [Accepted: 03/17/2018] [Indexed: 12/25/2022]
Affiliation(s)
- Stéphanie Hallée
- Centre de recherche en infectiologieCHU de Québec‐Université Laval Quebec City QC Canada
| | | | - Kathryn Matthews
- School of MedicineDeakin University Waurn Ponds 3216 VIC Australia
| | | | - Dave Richard
- Centre de recherche en infectiologieCHU de Québec‐Université Laval Quebec City QC Canada
| |
Collapse
|
60
|
Hallée S, Thériault C, Gagnon D, Kehrer J, Frischknecht F, Mair GR, Richard D. Identification of a Golgi apparatus protein complex important for the asexual erythrocytic cycle of the malaria parasite Plasmodium falciparum. Cell Microbiol 2018; 20:e12843. [PMID: 29579782 DOI: 10.1111/cmi.12843] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 03/09/2018] [Accepted: 03/09/2018] [Indexed: 12/01/2022]
Abstract
Compared with other eukaryotic cell types, malaria parasites appear to possess a more rudimentary Golgi apparatus being composed of dispersed, unstacked cis and trans-cisternae. Despite playing a central role in the secretory pathway of the parasite, few Plasmodium Golgi resident proteins have been characterised. We had previously identified a new Golgi resident protein of unknown function, which we had named Golgi Protein 1, and now show that it forms a complex with a previously uncharacterised transmembrane protein (Golgi Protein 2, GP2). The Golgi Protein complex localises to the cis-Golgi throughout the erythrocytic cycle and potentially also during the mosquito stages. Analysis of parasite strains where GP1 expression is conditionally repressed and/or the GP2 gene is inactivated reveals that though the Golgi protein complex is not essential at any stage of the parasite life cycle, it is important for optimal asexual development in the blood stages.
Collapse
Affiliation(s)
- Stéphanie Hallée
- Centre de recherche en infectiologie, CHU de Québec-Université Laval, Quebec City, Quebec, Canada
| | - Catherine Thériault
- Centre de recherche en infectiologie, CHU de Québec-Université Laval, Quebec City, Quebec, Canada
| | - Dominic Gagnon
- Centre de recherche en infectiologie, CHU de Québec-Université Laval, Quebec City, Quebec, Canada
| | - Jessica Kehrer
- Integrative Parasitology, Department of Infectious Diseases, University of Heidelberg Medical School, Heidelberg, Germany
| | - Friedrich Frischknecht
- Integrative Parasitology, Department of Infectious Diseases, University of Heidelberg Medical School, Heidelberg, Germany
| | - Gunnar R Mair
- Integrative Parasitology, Department of Infectious Diseases, University of Heidelberg Medical School, Heidelberg, Germany
| | - Dave Richard
- Centre de recherche en infectiologie, CHU de Québec-Université Laval, Quebec City, Quebec, Canada
| |
Collapse
|
61
|
Chisholm SA, Kalanon M, Nebl T, Sanders PR, Matthews KM, Dickerman BK, Gilson PR, de Koning-Ward TF. The malaria PTEX component PTEX88 interacts most closely with HSP101 at the host-parasite interface. FEBS J 2018; 285:2037-2055. [PMID: 29637707 DOI: 10.1111/febs.14463] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Revised: 03/08/2018] [Accepted: 04/03/2018] [Indexed: 12/28/2022]
Abstract
The pathogenic nature of malaria infections is due in part to the export of hundreds of effector proteins that actively remodel the host erythrocyte. The Plasmodium translocon of exported proteins (PTEX) has been shown to facilitate the trafficking of proteins into the host cell, a process that is essential for the survival of the parasite. The role of the auxiliary PTEX component PTEX88 remains unclear, as previous attempts to elucidate its function through reverse genetic approaches showed that in contrast to the core components PTEX150 and HSP101, knockdown of PTEX88 did not give rise to an export phenotype. Here, we have used biochemical approaches to understand how PTEX88 assembles within the translocation machinery. Proteomic analysis of the PTEX88 interactome showed that PTEX88 interacts closely with HSP101 but has a weaker affinity with the other core constituents of PTEX. PTEX88 was also found to associate with other PV-resident proteins, including chaperones and members of the exported protein-interacting complex that interacts with the major virulence factor PfEMP1, the latter contributing to cytoadherence and parasite virulence. Despite being expressed for the duration of the blood-stage life cycle, PTEX88 was only discretely observed at the parasitophorous vacuole membrane during ring stages and could not always be detected in the major high molecular weight complex that contains the other core components of PTEX, suggesting that its interaction with the PTEX complex may be dynamic. Together, these data have enabled the generation of an updated model of PTEX that now includes how PTEX88 assembles within the complex.
Collapse
Affiliation(s)
| | - Ming Kalanon
- School of Medicine, Deakin University, Waurn Ponds, Australia
| | - Thomas Nebl
- The Walter and Eliza Hall Institute, Parkville, Australia
| | - Paul R Sanders
- Burnet Institute, Prahran, Australia.,Monash University, Melbourne, Australia
| | | | | | - Paul R Gilson
- Burnet Institute, Prahran, Australia.,Monash University, Melbourne, Australia
| | | |
Collapse
|
62
|
Calcium-Dependent Protein Kinase 5 Is Required for Release of Egress-Specific Organelles in Plasmodium falciparum. mBio 2018; 9:mBio.00130-18. [PMID: 29487234 PMCID: PMC5829822 DOI: 10.1128/mbio.00130-18] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The human malaria parasite Plasmodium falciparum requires efficient egress out of an infected red blood cell for pathogenesis. This egress event is highly coordinated and is mediated by several signaling proteins, including the plant-like Pfalciparum calcium-dependent protein kinase 5 (PfCDPK5). Knockdown of PfCDPK5 results in an egress block where parasites are trapped inside their host cells. The mechanism of this PfCDPK5-dependent block, however, remains unknown. Here, we show that PfCDPK5 colocalizes with a specialized set of parasite organelles known as micronemes and is required for their discharge, implicating failure of this step as the cause of the egress defect in PfCDPK5-deficient parasites. Furthermore, we show that PfCDPK5 cooperates with the Pfalciparum cGMP-dependent kinase (PfPKG) to fully activate the protease cascade critical for parasite egress. The PfCDPK5-dependent arrest can be overcome by hyperactivation of PfPKG or by physical disruption of the arrested parasite, and we show that both treatments facilitate the release of the micronemes required for egress. Our results define the molecular mechanism of PfCDPK5 function and elucidate the complex signaling pathway of parasite egress.IMPORTANCE The signs and symptoms of clinical malaria result from the replication of parasites in human blood. Efficient egress of the malaria parasite Plasmodium falciparum out of an infected red blood cell is critical for pathogenesis. The Pfalciparum calcium-dependent protein kinase 5 (PfCDPK5) is essential for parasite egress. Following PfCDPK5 knockdown, parasites remain trapped inside their host cell and do not egress, but the mechanism for this block remains unknown. We show that PfCDPK5 colocalizes with parasite organelles known as micronemes. We demonstrate that PfCDPK5 is critical for the discharge of these micronemes and that failure of this step is the molecular mechanism of the parasite egress arrest. We also show that hyperactivation of the cGMP-dependent kinase PKG can overcome this arrest. Our data suggest that small molecules that inhibit the egress signaling pathway could be effective antimalarial therapeutics.
Collapse
|
63
|
Disrupting CD147-RAP2 interaction abrogates erythrocyte invasion by Plasmodium falciparum. Blood 2018; 131:1111-1121. [PMID: 29352039 DOI: 10.1182/blood-2017-08-802918] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Accepted: 01/08/2018] [Indexed: 11/20/2022] Open
Abstract
Effective vaccines against malaria caused by Plasmodium falciparum are still lacking, and the molecular mechanism of the host-parasite interaction is not fully understood. Here we demonstrate that the interaction of RAP2, a parasite-secreted rhoptry protein that functions in the parasitophorous vacuole formation stage of the invasion, and CD147 on the host erythrocyte is essential for erythrocyte invasion by P falciparum and is independent from all previously identified interactions involved. Importantly, the blockade of the CD147-RAP2 interaction by HP6H8, a humanized CD147 antibody, completely abolished the parasite invasion with both cure and preventative functions in a humanized mouse model. Together with its long half-life on human red blood cells and its safety profile in cynomolgus monkeys, HP6H8 is the first antibody that offers an advantageous approach by targeting a more conserved late-stage parasite ligand for preventing as well as treating severe malaria.
Collapse
|
64
|
Srisutham S, Saralamba N, Sriprawat K, Mayxay M, Smithuis F, Nosten F, Pukrittayakamee S, Day NPJ, Dondorp AM, Imwong M. Genetic diversity of three surface protein genes in Plasmodium malariae from three Asian countries. Malar J 2018; 17:24. [PMID: 29325573 PMCID: PMC5765603 DOI: 10.1186/s12936-018-2176-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Accepted: 01/08/2018] [Indexed: 01/07/2023] Open
Abstract
Background Genetic diversity of the three important antigenic proteins, namely thrombospondin-related anonymous protein (TRAP), apical membrane antigen 1 (AMA1), and 6-cysteine protein (P48/45), all of which are found in various developmental stages of Plasmodium parasites is crucial for targeted vaccine development. While studies related to the genetic diversity of these proteins are available for Plasmodium falciparum and Plasmodium vivax, barely enough information exists regarding Plasmodium malariae. The present study aims to demonstrate the genetic variations existing among these three genes in P. malariae by analysing their diversity at nucleotide and protein levels. Methods Three surface protein genes were isolated from 45 samples collected in Thailand (N = 33), Myanmar (N = 8), and Lao PDR (N = 4), using conventional polymerase chain reaction (PCR) assay. Then, the PCR products were sequenced and analysed using BioEdit, MEGA6, and DnaSP programs. Results The average pairwise nucleotide diversities (π) of P. malariae trap, ama1, and p48/45 were 0.00169, 0.00413, and 0.00029, respectively. The haplotype diversities (Hd) of P. malariae trap, ama1, and p48/45 were 0.919, 0.946, and 0.130, respectively. Most of the nucleotide substitutions were non-synonymous, which indicated that the genetic variations of these genes were maintained by positive diversifying selection, thus, suggesting their role as a potential target of protective immune response. Amino acid substitutions of P. malariae TRAP, AMA1, and P48/45 could be categorized to 17, 20, and 2 unique amino-acid variants, respectively. For further vaccine development, carboxyl terminal of P48/45 would be a good candidate according to conserved amino acid at low genetic diversity (π = 0.2–0.3). Conclusions High mutational diversity was observed in P. malariae trap and ama1 as compared to p48/45 in P. malariae samples isolated from Thailand, Myanmar, and Lao PDR. Taken together, these results suggest that P48/45 might be a good vaccine candidate against P. malariae infection because of its sufficiently low genetic diversity and highly conserved amino acids especially on the carboxyl end. Electronic supplementary material The online version of this article (10.1186/s12936-018-2176-x) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Suttipat Srisutham
- Department of Molecular Tropical Medicine and Genetics, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Naowarat Saralamba
- Department of Molecular Tropical Medicine and Genetics, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.,Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Kanlaya Sriprawat
- Shoklo Malaria Research Unit, Mahidol-Oxford Tropical Medicine Research Unit, Mae Sot, Thailand
| | - Mayfong Mayxay
- Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit (LOMWRU), Microbiology Laboratory, Mahosot Hospital, Vientiane, Lao People's Democratic Republic.,Faculty of Postgraduate Studies, University of Health Sciences, Vientiane, Lao People's Democratic Republic.,Centre for Tropical Medicine and Global Health, Churchill Hospital, University of Oxford, Oxford, UK
| | - Frank Smithuis
- Medical Action Myanmar, Yangon, Myanmar.,Centre for Tropical Medicine, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, OX3 7LF, UK
| | - Francois Nosten
- Shoklo Malaria Research Unit, Mahidol-Oxford Tropical Medicine Research Unit, Mae Sot, Thailand.,Centre for Tropical Medicine, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, OX3 7LF, UK
| | - Sasithon Pukrittayakamee
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.,Department of Clinical Tropical Medicine, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Nicholas P J Day
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.,Centre for Tropical Medicine and Global Health, Churchill Hospital, University of Oxford, Oxford, UK
| | - Arjen M Dondorp
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.,Centre for Tropical Medicine and Global Health, Churchill Hospital, University of Oxford, Oxford, UK
| | - Mallika Imwong
- Department of Molecular Tropical Medicine and Genetics, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand. .,Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
| |
Collapse
|
65
|
Evidence that the Plasmodium falciparum Protein Sortilin Potentially Acts as an Escorter for the Trafficking of the Rhoptry-Associated Membrane Antigen to the Rhoptries. mSphere 2018; 3:mSphere00551-17. [PMID: 29299530 PMCID: PMC5750388 DOI: 10.1128/msphere.00551-17] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Accepted: 12/06/2017] [Indexed: 12/11/2022] Open
Abstract
The rhoptry organelle is critical for the invasion of an erythrocyte by the malaria parasite Plasmodium falciparum. Despite their critical roles, the mechanisms behind their biogenesis are still poorly defined. Our earlier work had suggested that the interaction between the glycosylphosphatidylinositol (GPI)-anchored rhoptry-associated membrane antigen (RAMA) and the soluble rhoptry-associated protein 1 was involved in the transport of the latter from the Golgi apparatus to the rhoptry. However, how this protein complex could interact with the intracellular trafficking machinery was unknown at this stage. Here we show that the P. falciparum homologue of the transmembrane protein sortilin-VPS10 interacts with regions of RAMA that are sufficient to target a fluorescent reporter to the rhoptries. These results suggest that P. falciparum sortilin (PfSortilin) could potentially act as the escorter for the transport of rhoptry-destined cargo. IMPORTANCE The malaria parasite is a massive burden in several parts of the world. Worryingly, the parasite has become resistant to several of the drugs commonly used to treat the disease, and at this time, there is no commercial vaccine. It is therefore critical to identify new targets for the development of antimalarials. To survive in the human body, the malaria parasite needs to invade red blood cells. For this, it uses a variety of effectors stored in organelles forming a structure called the apical complex. The mechanisms behind how the parasite generates the apical complex are poorly understood. In this study, we present evidence that a transmembrane protein called sortilin potentially acts as an escorter to transport proteins from the Golgi apparatus to the rhoptries, a component of the apical complex. Our study provides new insight into the biogenesis of a critical structure of the malaria parasite.
Collapse
|
66
|
Ebrahimzadeh Z, Mukherjee A, Richard D. A map of the subcellular distribution of phosphoinositides in the erythrocytic cycle of the malaria parasite Plasmodium falciparum. Int J Parasitol 2017; 48:13-25. [PMID: 29154995 DOI: 10.1016/j.ijpara.2017.08.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 08/22/2017] [Accepted: 08/31/2017] [Indexed: 12/16/2022]
Abstract
Despite representing a small percentage of the cellular lipids of eukaryotic cells, phosphoinositides (PIPs) are critical in various processes such as intracellular trafficking and signal transduction. Central to their various functions is the differential distribution of PIP species to specific membrane compartments through the actions of kinases, phosphatases and lipases. Despite their importance in the malaria parasite lifecycle, the subcellular distribution of most PIP species in this organism is still unknown. We here localise several species of PIPs throughout the erythrocytic cycle of Plasmodium falciparum. We show that PI3P is mostly found at the apicoplast and the membrane of the food vacuole, that PI4P associates with the Golgi apparatus and the plasma membrane and that PI(4,5)P2, in addition to being detected at the plasma membrane, labels some cavity-like spherical structures. Finally, we show that the elusive PI5P localises to the plasma membrane, the nucleus and potentially to the transitional endoplasmic reticulum (ER). Our map of the subcellular distribution of PIP species in P. falciparum will be a useful tool to shed light on the dynamics of these lipids in this deadly parasite.
Collapse
Affiliation(s)
- Zeinab Ebrahimzadeh
- Centre de recherche en infectiologie, CRCHU de Québec-Université Laval, 2705 Boul. Laurier, Québec, QC G1V 4G2, Canada
| | - Angana Mukherjee
- Centre de recherche en infectiologie, CRCHU de Québec-Université Laval, 2705 Boul. Laurier, Québec, QC G1V 4G2, Canada
| | - Dave Richard
- Centre de recherche en infectiologie, CRCHU de Québec-Université Laval, 2705 Boul. Laurier, Québec, QC G1V 4G2, Canada.
| |
Collapse
|
67
|
Molecular mechanisms that mediate invasion and egress of malaria parasites from red blood cells. Curr Opin Hematol 2017; 24:208-214. [PMID: 28306665 DOI: 10.1097/moh.0000000000000334] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
PURPOSE OF REVIEW Malaria parasites invade and multiply in diverse host cells during their complex life cycle. Some blood stage parasites transform into male and female gametocytes that are transmitted by female anopheline mosquitoes. The gametocytes are activated in the mosquito midgut to form male and female gametes, which egress from RBCs to mate and form a zygote. Here, we will review our current understanding of the molecular mechanisms that mediate invasion and egress by malaria parasites at different life cycle stages. RECENT FINDINGS A number of key effector molecules such as parasite protein ligands for receptor-engagement during invasion as well as proteases and perforin-like proteins that mediate egress have been identified. Interestingly, these parasite-encoded effectors are located in internal, vesicular organelles and are secreted in a highly regulated manner during invasion and egress. Here, we will review our current understanding of the functional roles of these effectors as well as the signaling pathways that regulate their timely secretion with accurate spatiotemporal coordinates. SUMMARY Understanding the molecular basis of key processes such as host cell invasion and egress by malaria parasites could provide novel targets for development of inhibitors to block parasite growth and transmission.
Collapse
|
68
|
Singh S, Chitnis CE. Molecular Signaling Involved in Entry and Exit of Malaria Parasites from Host Erythrocytes. Cold Spring Harb Perspect Med 2017; 7:cshperspect.a026815. [PMID: 28507195 DOI: 10.1101/cshperspect.a026815] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
During the blood stage, Plasmodium spp. merozoites invade host red blood cells (RBCs), multiply, exit, and reinvade uninfected RBCs in a continuing cycle that is responsible for all the clinical symptoms associated with malaria. Entry into (invasion) and exit from (egress) RBCs are highly regulated processes that are mediated by an array of parasite proteins with specific functional roles. Many of these parasite proteins are stored in specialized apical secretory vesicles, and their timely release is critical for successful invasion and egress. For example, the discharge of parasite protein ligands to the apical surface of merozoites is required for interaction with host receptors to mediate invasion, and the timely discharge of proteases and pore-forming proteins helps in permeabilization and dismantling of limiting membranes during egress. This review focuses on our understanding of the signaling mechanisms that regulate apical organelle secretion during host cell invasion and egress by malaria parasites. The review also explores how understanding key signaling mechanisms in the parasite can open opportunities to develop novel strategies to target Plasmodium parasites and eliminate malaria.
Collapse
Affiliation(s)
- Shailja Singh
- Department of Parasites and Insect Vectors, Institut Pasteur, 75015 Paris, France.,Shiv Nadar University, Gautam Buddha Nagar, Uttar Pradesh 201314, India
| | - Chetan E Chitnis
- Department of Parasites and Insect Vectors, Institut Pasteur, 75015 Paris, France.,Malaria Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi 110067, India
| |
Collapse
|
69
|
Arévalo-Pinzón G, Bermúdez M, Hernández D, Curtidor H, Patarroyo MA. Plasmodium vivax ligand-receptor interaction: PvAMA-1 domain I contains the minimal regions for specific interaction with CD71+ reticulocytes. Sci Rep 2017; 7:9616. [PMID: 28855657 PMCID: PMC5577344 DOI: 10.1038/s41598-017-10025-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Accepted: 08/02/2017] [Indexed: 12/18/2022] Open
Abstract
The malarial parasite’s invasion is complex, active and coordinated, involving many low and high affinity interactions with receptors on target cell membrane. Proteomics analysis has described around 40 proteins in P. vivax which could be involved in reticulocyte invasion; few have been studied with the aim of elucidating how many of them establish specific interactions with their respective host cells. Given the importance of knowing which of the parasite’s protein regions are functionally important for invasion, minimum regions mediating specific interaction between Plasmodium vivax apical membrane antigen 1 (PvAMA-1) and its host cell were here elucidated. The region covering PvAMA-1 domains I and II (PvAMA-DI-II) specifically bound to the CD71+ red blood cell subpopulation. A 20 residue-long region (81EVENAKYRIPAGRCPVFGKG100) located in domain I was capable of inhibiting PvAMA-DI-II recombinant protein binding to young reticulocytes (CD71+CD45−) and rosette formation. This conserved peptide specifically interacted with high affinity with reticulocytes (CD71+) through a neuraminidase- and chymotrypsin-treatment sensitive receptor. Such results showed that, despite AMA-1 having universal functions during late Plasmodium invasion stages, PvAMA-1 had reticulocyte-preferring binding regions, suggesting that P. vivax target cell selection is not just restricted to initial interactions but maintained throughout the erythrocyte invasion cycle, having important implications for designing a specific anti-P. vivax vaccine.
Collapse
Affiliation(s)
- Gabriela Arévalo-Pinzón
- Fundación Instituto de Inmunología de Colombia (FIDIC), Carrera 50 # 26-20, Bogotá, Colombia.,PhD Program in Biomedical and Biological Sciences, Universidad del Rosario, Carrera 24 #, 63C-69, Bogotá, Colombia
| | - Maritza Bermúdez
- Fundación Instituto de Inmunología de Colombia (FIDIC), Carrera 50 # 26-20, Bogotá, Colombia.,MSc Program in Biological Sciences, Pontificia Universidad Javeriana, Carrera 7 # 40-62, Bogotá, Colombia
| | - Diana Hernández
- Fundación Instituto de Inmunología de Colombia (FIDIC), Carrera 50 # 26-20, Bogotá, Colombia
| | - Hernando Curtidor
- Fundación Instituto de Inmunología de Colombia (FIDIC), Carrera 50 # 26-20, Bogotá, Colombia.,School of Medicine and Health Sciences, Universidad del Rosario, Carrera 24 #, 63C-69, Bogotá, Colombia
| | - Manuel Alfonso Patarroyo
- Fundación Instituto de Inmunología de Colombia (FIDIC), Carrera 50 # 26-20, Bogotá, Colombia. .,School of Medicine and Health Sciences, Universidad del Rosario, Carrera 24 #, 63C-69, Bogotá, Colombia.
| |
Collapse
|
70
|
Abstract
It is only in the last decade that sub-cellular resolution of red cell invasion by the malaria parasite Plasmodium falciparum has been possible. Here we look back on the development of methodologies that led to this possibility and the subsequent advancements made in understanding this key event in malaria disease.
Collapse
Affiliation(s)
- Jake Baum
- Department of Life Sciences, Imperial College London, London SW7 2AZ, UK.
| | - Dave Richard
- Department of Microbiology, Infectious Diseases, and Immunology, Laval University, Quebec City, QC G1V 0A6, Canada
| | - David T Riglar
- Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA; Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA
| |
Collapse
|
71
|
Vulliez-Le Normand B, Saul FA, Hoos S, Faber BW, Bentley GA. Cross-reactivity between apical membrane antgen 1 and rhoptry neck protein 2 in P. vivax and P. falciparum: A structural and binding study. PLoS One 2017; 12:e0183198. [PMID: 28817634 PMCID: PMC5560645 DOI: 10.1371/journal.pone.0183198] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Accepted: 07/31/2017] [Indexed: 02/03/2023] Open
Abstract
Malaria, a disease endemic in many tropical and subtropical regions, is caused by infection of the erythrocyte by the apicomplexan parasite Plasmodium. Host-cell invasion is a complex process but two Plasmodium proteins, Apical Membrane Antigen 1 (AMA1) and the Rhoptry Neck protein complex (RON), play a key role. AMA1, present on the surface of the parasite, binds tightly to the RON2 component of the RON protein complex, which is inserted into the erythrocyte membrane during invasion. Blocking the AMA1-RON2 interaction with antibodies or peptides inhibits invasion, underlining its importance in the Plasmodium life cycle and as a target for therapeutic strategies. We describe the crystal structure of the complex formed between AMA1 from P. vivax (PvAMA1) and a peptide derived from the externally exposed region of P. vivax RON2 (PvRON2sp1), and of the heterocomplex formed between P. falciparum AMA1 (PfAMA1) and PvRON2sp1. Binding studies show that the affinity of PvRON2sp1 for PvAMA1 is weaker than that previously reported for the PfRON2sp1-PfAMA1 association. Moreover, while PvRON2sp1 shows strong cross-reactivity with PfAMA1, PfRON2sp1 displays no detectable interaction with PvAMA1. The structures show that the equivalent residues PvRON2-Thr2055 and PfRON2-Arg2041 largely account for this pattern of reactivity.
Collapse
Affiliation(s)
- Brigitte Vulliez-Le Normand
- Institut Pasteur, Unité de Microbiologie Structurale, Département de Biologie Structurale et Chimie, Centre National de la Recherche Scientifique, UMR 3528, Université Paris Diderot, Sorbonne Paris Cité, Microbiologie Structurale, Paris, France
| | - Frederick A. Saul
- Institut Pasteur, Plate-forme de Cristallographie, Département de Biologie Structurale et Chimie, Centre National de la Recherche Scientifique UMR 3528, Paris, France
| | - Sylviane Hoos
- Institut Pasteur, Plate-Forme de Biophysique Moléculaire, Département de Biologie Structurale et Chimie, Centre National de la Recherche Scientifique UMR 3528, Paris, France
| | - Bart W. Faber
- Department of Parasitology, Biomedical Primate Research Centre, Rijswijk, The Netherlands
| | - Graham A. Bentley
- Institut Pasteur, Unité d’Immunologie Structurale, Département de Biologie Structurale et Chimie, Centre National de la Recherche Scientifique, URA 2185, Paris, France
- * E-mail:
| |
Collapse
|
72
|
Molecular Cloning and Characterization of Babesia orientalis Rhoptry Neck 2 BoRON2 Protein. J Parasitol Res 2017; 2017:7259630. [PMID: 28775897 PMCID: PMC5523350 DOI: 10.1155/2017/7259630] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2016] [Revised: 04/12/2017] [Accepted: 04/30/2017] [Indexed: 11/24/2022] Open
Abstract
Babesiosis caused by Babesia orientalis is one of the most prevalent infections of water buffalo transmitted by Rhipicephalus haemaphysaloides causing a parasitic and hemolytic disease. The organelles proteins localized in apical membrane especially rhoptries neck and microneme protein form a complex called moving junction important during invasion process of parasites belonging to apicomplexan group, including Babesia species. A truncated fragment coding a 936 bps fragment was cloned in pMD-19T and subcloned into pET32 (a)+ expression vector, expressed in E. coli BL21. Purified recombinant BoRON2 was used to produce polyclonal antibody against BoRON2. Here, we identified the full sequence of gene encoding the rhoptry neck 2 protein that we named BoRON2 which is 4035 bp in full-length open reading frame without introns, encoding a polypeptide of 1345 amino acids. Western blot of rBoRON2 probed with buffalo positive serum analysis revealed a band of around 150 kDa in parasite lysates, suggesting an active involvement during invasion process. These findings most likely are constructive in perspective of ongoing research focused particularly on water buffalo babesiosis prevention and therapeutics and globally provide new information for genes comparative analysis.
Collapse
|
73
|
PfCDPK1 mediated signaling in erythrocytic stages of Plasmodium falciparum. Nat Commun 2017; 8:63. [PMID: 28680058 PMCID: PMC5498596 DOI: 10.1038/s41467-017-00053-1] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Accepted: 04/26/2017] [Indexed: 01/11/2023] Open
Abstract
Calcium Dependent Protein Kinases are key effectors of calcium signaling in malaria parasite. PfCDPK1 is critical for asexual development of Plasmodium falciparum, but its precise function and substrates remain largely unknown. Using a conditional knockdown strategy, we here establish that this kinase is critical for the invasion of host erythrocytes. Furthermore, using a multidisciplinary approach involving comparative phosphoproteomics we gain insights into the underlying molecular mechanisms. We identify substrates of PfCDPK1, which includes proteins of Inner Membrane Complex and glideosome-actomyosin motor assembly. Interestingly, PfCDPK1 phosphorylates PfPKA regulatory subunit (PfPKA-R) and regulates PfPKA activity in the parasite, which may be relevant for the process of invasion. This study delineates the signaling network of PfCDPK1 and sheds light on mechanisms via which it regulates invasion.Calcium dependent protein kinase 1 (CDPK1) plays an important role in asexual development of Plasmodium falciparum. Using phosphoproteomics and conditional knockdown of CDPK1, the authors here identify CDPK1 substrates and a cross-talk between CDPK1 and PKA, and show the role of CDPK1 in parasite invasion.
Collapse
|
74
|
Yang ASP, Lopaticki S, O'Neill MT, Erickson SM, Douglas DN, Kneteman NM, Boddey JA. AMA1 and MAEBL are important for Plasmodium falciparum sporozoite infection of the liver. Cell Microbiol 2017; 19. [PMID: 28371168 DOI: 10.1111/cmi.12745] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 03/23/2017] [Accepted: 03/28/2017] [Indexed: 12/20/2022]
Abstract
The malaria sporozoite injected by a mosquito migrates to the liver by traversing host cells. The sporozoite also traverses hepatocytes before invading a terminal hepatocyte and developing into exoerythrocytic forms. Hepatocyte infection is critical for parasite development into merozoites that infect erythrocytes, and the sporozoite is thus an important target for antimalarial intervention. Here, we investigated two abundant sporozoite proteins of the most virulent malaria parasite Plasmodium falciparum and show that they play important roles during cell traversal and invasion of human hepatocytes. Incubation of P. falciparum sporozoites with R1 peptide, an inhibitor of apical merozoite antigen 1 (AMA1) that blocks merozoite invasion of erythrocytes, strongly reduced cell traversal activity. Consistent with its inhibitory effect on merozoites, R1 peptide also reduced sporozoite entry into human hepatocytes. The strong but incomplete inhibition prompted us to study the AMA-like protein, merozoite apical erythrocyte-binding ligand (MAEBL). MAEBL-deficient P. falciparum sporozoites were severely attenuated for cell traversal activity and hepatocyte entry in vitro and for liver infection in humanized chimeric liver mice. This study shows that AMA1 and MAEBL are important for P. falciparum sporozoites to perform typical functions necessary for infection of human hepatocytes. These two proteins therefore have important roles during infection at distinct points in the life cycle, including the blood, mosquito, and liver stages.
Collapse
Affiliation(s)
- Annie S P Yang
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia.,Department of Medical Biology, The University of Melbourne, Parkville, Victoria, Australia
| | - Sash Lopaticki
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
| | - Matthew T O'Neill
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
| | - Sara M Erickson
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia.,Department of Medical Biology, The University of Melbourne, Parkville, Victoria, Australia
| | - Donna N Douglas
- Department of Surgery, University of Alberta, Edmonton, Alberta, Canada
| | - Norman M Kneteman
- Department of Surgery, University of Alberta, Edmonton, Alberta, Canada
| | - Justin A Boddey
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia.,Department of Medical Biology, The University of Melbourne, Parkville, Victoria, Australia
| |
Collapse
|
75
|
Ghosh S, Kennedy K, Sanders P, Matthews K, Ralph SA, Counihan NA, de Koning-Ward TF. ThePlasmodiumrhoptry associated protein complex is important for parasitophorous vacuole membrane structure and intraerythrocytic parasite growth. Cell Microbiol 2017; 19. [DOI: 10.1111/cmi.12733] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Revised: 01/13/2017] [Accepted: 02/09/2017] [Indexed: 01/15/2023]
Affiliation(s)
- Sreejoyee Ghosh
- School of Medicine; Deakin University; Waurn Ponds Victoria Australia
| | - Kit Kennedy
- Department of Biochemistry and Molecular Biology; Bio21 Molecular Science and Biotechnology Institute; Melbourne Victoria Australia
| | - Paul Sanders
- The Burnet Institute; Melbourne Victoria Australia
| | - Kathryn Matthews
- School of Medicine; Deakin University; Waurn Ponds Victoria Australia
| | - Stuart A. Ralph
- Department of Biochemistry and Molecular Biology; Bio21 Molecular Science and Biotechnology Institute; Melbourne Victoria Australia
| | | | | |
Collapse
|
76
|
A novel Pfs38 protein complex on the surface of Plasmodium falciparum blood-stage merozoites. Malar J 2017; 16:79. [PMID: 28202027 PMCID: PMC5312596 DOI: 10.1186/s12936-017-1716-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Accepted: 01/28/2017] [Indexed: 11/10/2022] Open
Abstract
Background The Plasmodium genome encodes for a number of 6-Cys proteins that contain a module of six cysteine residues forming three intramolecular disulphide bonds. These proteins have been well characterized at transmission as well as hepatic stages of the parasite life cycle. In the present study, a large complex of 6-Cys proteins: Pfs41, Pfs38 and Pfs12 and three other merozoite surface proteins: Glutamate-rich protein (GLURP), SERA5 and MSP-1 were identified on the Plasmodium falciparum merozoite surface. Methods Recombinant 6-cys proteins i.e. Pfs38, Pfs12, Pfs41 as well as PfMSP-165 were expressed and purified using Escherichia coli expression system and antibodies were raised against each of these proteins. These antibodies were used to immunoprecipitate the native proteins and their associated partners from parasite lysate. ELISA, Far western, surface plasmon resonance and glycerol density gradient fractionation were carried out to confirm the respective interactions. Furthermore, erythrocyte binding assay with 6-cys proteins were undertaken to find out their possible role in host-parasite infection and seropositivity was assessed using Indian and Liberian sera. Results Immunoprecipitation of parasite-derived polypeptides, followed by LC–MS/MS analysis, identified a large Pfs38 complex comprising of 6-cys proteins: Pfs41, Pfs38, Pfs12 and other merozoite surface proteins: GLURP, SERA5 and MSP-1. The existence of such a complex was further corroborated by several protein–protein interaction tools, co-localization and co-sedimentation analysis. Pfs38 protein of Pfs38 complex binds to host red blood cells (RBCs) directly via glycophorin A as a receptor. Seroprevalence analysis showed that of the six antigens, prevalence varied from 40 to 99%, being generally highest for MSP-165 and GLURP proteins. Conclusions Together the data show the presence of a large Pfs38 protein-associated complex on the parasite surface which is involved in RBC binding. These results highlight the complex molecular interactions among the P. falciparum merozoite surface proteins and advocate the development of a multi-sub-unit malaria vaccine based on some of these protein complexes on merozoite surface. Electronic supplementary material The online version of this article (doi:10.1186/s12936-017-1716-0) contains supplementary material, which is available to authorized users.
Collapse
|
77
|
Devine SM, MacRaild CA, Norton RS, Scammells PJ. Antimalarial drug discovery targeting apical membrane antigen 1. MEDCHEMCOMM 2017; 8:13-20. [PMID: 30108688 PMCID: PMC6072474 DOI: 10.1039/c6md00495d] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Accepted: 10/27/2016] [Indexed: 01/06/2023]
Abstract
Malaria continues to frustrate humanity's attempts to eradicate this deadly disease. Although gains have been made over the last 15 years, drug resistance to malaria continues to be a major concern. The lack of new antimalarials with novel mechanisms of action continues to challenge the scientific community to find innovative targets to combat this persistent disease. One such target, apical membrane antigen 1 (AMA1), is an essential protein that helps the parasite invade host erythrocytes. Recently, a number of efforts have focused on the druggability of this target, aiming to block the interactions of AMA1 that mediate invasion of host cells. This review covers recent progress in drug discovery targeting this crucial protein-protein interaction in malaria.
Collapse
Affiliation(s)
- Shane M Devine
- Medicinal Chemistry , Monash Institute of Pharmaceutical Sciences , Monash University , Parkville , VIC 3052 , Australia . ;
| | - Christopher A MacRaild
- Medicinal Chemistry , Monash Institute of Pharmaceutical Sciences , Monash University , Parkville , VIC 3052 , Australia . ;
| | - Raymond S Norton
- Medicinal Chemistry , Monash Institute of Pharmaceutical Sciences , Monash University , Parkville , VIC 3052 , Australia . ;
| | - Peter J Scammells
- Medicinal Chemistry , Monash Institute of Pharmaceutical Sciences , Monash University , Parkville , VIC 3052 , Australia . ;
| |
Collapse
|
78
|
Zhu X, Zhao P, Wang S, Liu F, Liu J, Wang J, Yang Z, Yan G, Fan Q, Cao Y, Cui L. Analysis of Pvama1 genes from China-Myanmar border reveals little regional genetic differentiation of Plasmodium vivax populations. Parasit Vectors 2016; 9:614. [PMID: 27899135 PMCID: PMC5129220 DOI: 10.1186/s13071-016-1899-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2016] [Accepted: 11/21/2016] [Indexed: 12/22/2022] Open
Abstract
Background With the premise of diminishing parasite genetic diversity following the reduction of malaria incidence, the analysis of polymorphic antigenic markers may provide important information about the impact of malaria control on local parasite populations. Here we evaluated the genetic diversity of Plasmodium vivax apical membrane antigen 1 (Pvama1) gene in a parasite population from the China-Myanmar border and compared it with global P. vivax populations. Methods We performed evolutionary analysis to examine the genetic diversity, natural selection, and population differentiation of 73 Pvama1 sequences acquired from the China-Myanmar border as well as 615 publically available Pvama1 sequences from seven global P. vivax populations. Results A total of 308 Pvama1 haplotypes were identified among the global P. vivax isolates. The overall nucleotide diversity of Pvama1 gene among the 73 China-Myanmar border parasite isolates was 0.008 with 41 haplotypes being identified (Hd = 0.958). Domain I (DI) harbored the majority (26/33) of the polymorphic sites. The McDonald Kreitman test showed a significant positive selection across the ectodomain and the DI of Pvama1. The fixation index (FST) estimation between the China-Myanmar border, Thailand (0.01) and Myanmar (0.10) showed only slight geographical genetic differentiation. Notably, the Sal-I haplotype was not detected in any of the analyzed global isolates, whereas the Belem strain was restricted to the Thai population. The detected mutations are mapped outside the overlapped region of the predicted B-cell epitopes and intrinsically unstructured/disordered regions. Conclusions This study revealed high levels of genetic diversity of Pvama1 in the P. vivax parasite population from the China-Myanmar border with DI displaying stronger diversifying selection than other domains. There were low levels of population subdivision among parasite populations from the Greater Mekong Subregion. Electronic supplementary material The online version of this article (doi:10.1186/s13071-016-1899-1) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Xiaotong Zhu
- Department of Immunology, College of Basic Medical Science, China Medical University, Shenyang, Liaoning, 110122, China
| | - Pan Zhao
- Department of Microbiology and Parasitology, College of Basic Medical Sciences, China Medical University, Shenyang, Liaoning, 110122, China
| | - Si Wang
- Department of Microbiology and Parasitology, College of Basic Medical Sciences, China Medical University, Shenyang, Liaoning, 110122, China
| | - Fei Liu
- Department of Immunology, College of Basic Medical Science, China Medical University, Shenyang, Liaoning, 110122, China
| | - Jun Liu
- Department of Immunology, College of Basic Medical Science, China Medical University, Shenyang, Liaoning, 110122, China
| | - Jian Wang
- Department of Microbiology and Parasitology, College of Basic Medical Sciences, China Medical University, Shenyang, Liaoning, 110122, China
| | - Zhaoqing Yang
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Guiyun Yan
- Program in Public Health, University of California, Irvine, CA, USA
| | - Qi Fan
- Dalian Institute of Biotechnology, Dalian, Liaoning, China
| | - Yaming Cao
- Department of Immunology, College of Basic Medical Science, China Medical University, Shenyang, Liaoning, 110122, China.
| | - Liwang Cui
- Department of Immunology, College of Basic Medical Science, China Medical University, Shenyang, Liaoning, 110122, China. .,Department of Entomology, The Pennsylvania State University, University Park, PA, 16802, USA.
| |
Collapse
|
79
|
Abstract
Over the past decade, major advances in imaging techniques have enhanced our understanding of Plasmodium spp. parasites and their interplay with mammalian hosts and mosquito vectors. Cryoelectron tomography, cryo-X-ray tomography and super-resolution microscopy have shifted paradigms of sporozoite and gametocyte structure, the process of erythrocyte invasion by merozoites, and the architecture of Maurer's clefts. Intravital time-lapse imaging has been revolutionary for our understanding of pre-erythrocytic stages of rodent Plasmodium parasites. Furthermore, high-speed imaging has revealed the link between sporozoite structure and motility, and improvements in time-lapse microscopy have enabled imaging of the entire Plasmodium falciparum erythrocytic cycle and the complete Plasmodium berghei pre-erythrocytic stages for the first time. In this Review, we discuss the contribution of key imaging tools to these and other discoveries in the malaria field over the past 10 years.
Collapse
|
80
|
Yang ASP, Boddey JA. Molecular mechanisms of host cell traversal by malaria sporozoites. Int J Parasitol 2016; 47:129-136. [PMID: 27825827 DOI: 10.1016/j.ijpara.2016.09.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Revised: 07/22/2016] [Accepted: 09/05/2016] [Indexed: 11/19/2022]
Abstract
Malaria is a pernicious infectious disease caused by apicomplexan parasites of the genus Plasmodium. Each year, malaria afflicts over 200million people, causing considerable morbidity, loss to gross domestic product of endemic countries, and more than 420,000 deaths. A central feature of the virulence of malaria parasites is the ability of sporozoite forms injected by a mosquito to navigate from the inoculation site in the skin through host tissues to infect the liver. The ability for sporozoites to traverse through different host cell types is very important for the successful development of parasites within the mammalian host. Over the past decade, our understanding of the role of host cell traversal has become clearer through important studies with rodent models of malaria. However, we still do not understand the stepwise process of host cell entry and exit or know the molecular mechanisms governing each step. We know even less about cell traversal by malaria parasite species that infect humans. Here, we review current knowledge regarding the role and molecular mechanisms of sporozoite cell traversal and highlight recent advances that prompt new ways of thinking about this important process.
Collapse
Affiliation(s)
- Annie S P Yang
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC 3052, Australia; Department of Medical Biology, University of Melbourne, Parkville, VIC 3052, Australia
| | - Justin A Boddey
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC 3052, Australia; Department of Medical Biology, University of Melbourne, Parkville, VIC 3052, Australia.
| |
Collapse
|
81
|
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: 9] [Impact Index Per Article: 1.1] [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.
Collapse
|
82
|
Hierarchical phosphorylation of apical membrane antigen 1 is required for efficient red blood cell invasion by malaria parasites. Sci Rep 2016; 6:34479. [PMID: 27698395 PMCID: PMC5048298 DOI: 10.1038/srep34479] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Accepted: 09/08/2016] [Indexed: 12/03/2022] Open
Abstract
Central to the pathogenesis of malaria is the proliferation of Plasmodium falciparum parasites within human erythrocytes. Parasites invade erythrocytes via a coordinated sequence of receptor-ligand interactions between the parasite and host cell. One key ligand, Apical Membrane Antigen 1 (AMA1), is a leading blood-stage vaccine and previous work indicates that phosphorylation of its cytoplasmic domain (CPD) is important to its function during invasion. Here we investigate the significance of each of the six available phospho-sites in the CPD. We confirm that the cyclic AMP/protein kinase A (PKA) signalling pathway elicits a phospho-priming step upon serine 610 (S610), which enables subsequent phosphorylation in vitro of a conserved, downstream threonine residue (T613) by glycogen synthase kinase 3 (GSK3). Both phosphorylation steps are required for AMA1 to function efficiently during invasion. This provides the first evidence that the functions of key invasion ligands of the malaria parasite are regulated by sequential phosphorylation steps.
Collapse
|
83
|
Wang G, Drinkwater N, Drew DR, MacRaild CA, Chalmers DK, Mohanty B, Lim SS, Anders RF, Beeson JG, Thompson PE, McGowan S, Simpson JS, Norton RS, Scanlon MJ. Structure–Activity Studies of β-Hairpin Peptide Inhibitors of the Plasmodium falciparum AMA1–RON2 Interaction. J Mol Biol 2016; 428:3986-3998. [DOI: 10.1016/j.jmb.2016.07.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2016] [Revised: 06/25/2016] [Accepted: 07/04/2016] [Indexed: 12/01/2022]
|
84
|
Han H, Xue P, Dong H, Zhu S, Zhao Q, Huang B. Screening and characterization of apical membrane antigen 1 interacting proteins in Eimeria tenella. Exp Parasitol 2016; 170:116-124. [PMID: 27693220 DOI: 10.1016/j.exppara.2016.09.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Revised: 09/15/2016] [Accepted: 09/27/2016] [Indexed: 10/20/2022]
Abstract
Avian coccidiosis is a widespread and economically significant disease of poultry. It is an enteric disease caused by several protozoan Eimeria species. Eimeria belongs to the phylum Apicomplexa, which exhibits an unusual mechanism of host cell invasion. During invasion of host cells, the protein apical membrane antigen 1 (AMA1) is essential for invasion of Toxoplasma gondii and Plasmodium. Contrary to the roles of AMA1 during host cell invasion in T. gondii and Plasmodium, the precise functions of Eimeria AMA1 (EtAMA1) are unclear. In order to study the functions of EtAMA1, a yeast two-hybrid cDNA library was constructed from E. tenella sporozoites. The EtAMA1 ectodomain was cloned into the pGBKT7 vector to construct the bait plasmid pGBKT7- EtAMA1. Autoactivation and toxicity of the bait protein in yeast cells were tested by comparison with the pGBKT7 empty vector. Expression of the bait protein was detected by western blots. The bait plasmid pGBKT7-EtAMA1 was used to screen yeast two-hybrid cDNA library from E. tenella sporozoites. After multiple screenings with high-screening-rate medium and exclusion of false-positive plasmids, positive preys were sequenced and analyzed using BLAST. We obtained 14 putative EtAMA1-interacting proteins including E. tenella acidic microneme protein2 (EtMIC2), E. tenella putative cystathionine beta-synthase, E. tenella Eimeria-specific protein, four E. tenella conserved hypothetical proteins (one in the serine/threonine protein kinase family) and seven unknown proteins. Gene Ontology analysis indicated that two known proteins were associated with metabolic process, pyridoxal phosphate binding and protein phosphorylation. Functional analysis indicated EtMIC2 was implicated in parasite motility, migration, recognition and invasion of host cells. The data suggested that EtAMA1 may be important during host cell invasion, but also involved in other biological processes.
Collapse
Affiliation(s)
- Hongyu Han
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Key Laboratory of Animal Parasitology of Ministry of Agriculture, Minhang, Shanghai, 200241, PR China
| | - Pu Xue
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Key Laboratory of Animal Parasitology of Ministry of Agriculture, Minhang, Shanghai, 200241, PR China
| | - Hui Dong
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Key Laboratory of Animal Parasitology of Ministry of Agriculture, Minhang, Shanghai, 200241, PR China
| | - Shunhai Zhu
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Key Laboratory of Animal Parasitology of Ministry of Agriculture, Minhang, Shanghai, 200241, PR China
| | - Qiping Zhao
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Key Laboratory of Animal Parasitology of Ministry of Agriculture, Minhang, Shanghai, 200241, PR China
| | - Bing Huang
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Key Laboratory of Animal Parasitology of Ministry of Agriculture, Minhang, Shanghai, 200241, PR China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, 225009, PR China.
| |
Collapse
|
85
|
Aniweh Y, Gao X, Gunalan K, Preiser PR. PfRH2b specific monoclonal antibodies inhibit merozoite invasion. Mol Microbiol 2016; 102:386-404. [DOI: 10.1111/mmi.13468] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/18/2016] [Indexed: 11/28/2022]
Affiliation(s)
- Yaw Aniweh
- Division of Molecular Genetics and Cell biology, School of Biological Sciences; Nanyang Technological University; 637551 Singapore
| | - Xiaohong Gao
- Division of Molecular Genetics and Cell biology, School of Biological Sciences; Nanyang Technological University; 637551 Singapore
| | - Karthigayan Gunalan
- Division of Molecular Genetics and Cell biology, School of Biological Sciences; Nanyang Technological University; 637551 Singapore
| | - Peter R. Preiser
- Division of Molecular Genetics and Cell biology, School of Biological Sciences; Nanyang Technological University; 637551 Singapore
| |
Collapse
|
86
|
Norton RS, Leung EWW, Chandrashekaran IR, MacRaild CA. Applications of (19)F-NMR in Fragment-Based Drug Discovery. Molecules 2016; 21:molecules21070860. [PMID: 27438818 PMCID: PMC6273323 DOI: 10.3390/molecules21070860] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Revised: 06/21/2016] [Accepted: 06/21/2016] [Indexed: 11/16/2022] Open
Abstract
(19)F-NMR has proved to be a valuable tool in fragment-based drug discovery. Its applications include screening libraries of fluorinated fragments, assessing competition among elaborated fragments and identifying the binding poses of promising hits. By observing fluorine in both the ligand and the target protein, useful information can be obtained on not only the binding pose but also the dynamics of ligand-protein interactions. These applications of (19)F-NMR will be illustrated in this review with studies from our fragment-based drug discovery campaigns against protein targets in parasitic and infectious diseases.
Collapse
Affiliation(s)
- Raymond S Norton
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville 3052, Australia.
| | - Eleanor W W Leung
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville 3052, Australia.
| | - Indu R Chandrashekaran
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville 3052, Australia.
| | - Christopher A MacRaild
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville 3052, Australia.
| |
Collapse
|
87
|
Essential Role of the PfRh5/PfRipr/CyRPA Complex during Plasmodium falciparum Invasion of Erythrocytes. Cell Host Microbe 2016; 20:60-71. [DOI: 10.1016/j.chom.2016.06.004] [Citation(s) in RCA: 129] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Revised: 04/05/2016] [Accepted: 05/18/2016] [Indexed: 01/30/2023]
|
88
|
Vetrivel U, Muralikumar S, Mahalakshmi B, Lily Therese K, Madhavan HN, Alameen M, Thirumudi I. Multilevel Precision-Based Rational Design of Chemical Inhibitors Targeting the Hydrophobic Cleft of Toxoplasma gondii Apical Membrane Antigen 1 (AMA1). Genomics Inform 2016; 14:53-61. [PMID: 27445648 PMCID: PMC4951401 DOI: 10.5808/gi.2016.14.2.53] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Revised: 04/06/2016] [Accepted: 04/08/2016] [Indexed: 11/20/2022] Open
Abstract
Toxoplasma gondii is an intracellular Apicomplexan parasite and a causative agent of toxoplasmosis in human. It causes encephalitis, uveitis, chorioretinitis, and congenital infection. T. gondii invades the host cell by forming a moving junction (MJ) complex. This complex formation is initiated by intermolecular interactions between the two secretory parasitic proteins-namely, apical membrane antigen 1 (AMA1) and rhoptry neck protein 2 (RON2) and is critically essential for the host invasion process. By this study, we propose two potential leads, NSC95522 and NSC179676 that can efficiently target the AMA1 hydrophobic cleft, which is a hotspot for targeting MJ complex formation. The proposed leads are the result of an exhaustive conformational search-based virtual screen with multilevel precision scoring of the docking affinities. These two compounds surpassed all the precision levels of docking and also the stringent post docking and cumulative molecular dynamics evaluations. Moreover, the backbone flexibility of hotspot residues in the hydrophobic cleft, which has been previously reported to be essential for accommodative binding of RON2 to AMA1, was also highly perturbed by these compounds. Furthermore, binding free energy calculations of these two compounds also revealed a significant affinity to AMA1. Machine learning approaches also predicted these two compounds to possess more relevant activities. Hence, these two leads, NSC95522 and NSC179676, may prove to be potential inhibitors targeting AMA1-RON2 complex formation towards combating toxoplasmosis.
Collapse
Affiliation(s)
- Umashankar Vetrivel
- Centre for Bioinformatics, Kamalnayan Bajaj Institute for Research in Vision and Ophthalmology, Vision Research Foundation, Sankara Nethralaya, Chennai 600-006, India
| | - Shalini Muralikumar
- Centre for Bioinformatics, Kamalnayan Bajaj Institute for Research in Vision and Ophthalmology, Vision Research Foundation, Sankara Nethralaya, Chennai 600-006, India
| | - B Mahalakshmi
- L&T Microbiology Research Centre, Kamalnayan Bajaj Institute for Research in Vision and Ophthalmology, Vision Research Foundation, Sankara Nethralaya, Chennai 600-006, India
| | - K Lily Therese
- L&T Microbiology Research Centre, Kamalnayan Bajaj Institute for Research in Vision and Ophthalmology, Vision Research Foundation, Sankara Nethralaya, Chennai 600-006, India
| | - H N Madhavan
- L&T Microbiology Research Centre, Kamalnayan Bajaj Institute for Research in Vision and Ophthalmology, Vision Research Foundation, Sankara Nethralaya, Chennai 600-006, India
| | - Mohamed Alameen
- Centre for Bioinformatics, Kamalnayan Bajaj Institute for Research in Vision and Ophthalmology, Vision Research Foundation, Sankara Nethralaya, Chennai 600-006, India
| | - Indhuja Thirumudi
- Centre for Bioinformatics, Kamalnayan Bajaj Institute for Research in Vision and Ophthalmology, Vision Research Foundation, Sankara Nethralaya, Chennai 600-006, India
| |
Collapse
|
89
|
Weiss GE, Crabb BS, Gilson PR. Overlaying Molecular and Temporal Aspects of Malaria Parasite Invasion. Trends Parasitol 2016; 32:284-295. [DOI: 10.1016/j.pt.2015.12.007] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Revised: 12/02/2015] [Accepted: 12/10/2015] [Indexed: 12/31/2022]
|
90
|
Satchwell TJ. Erythrocyte invasion receptors for Plasmodium falciparum: new and old. Transfus Med 2016; 26:77-88. [PMID: 26862042 DOI: 10.1111/tme.12280] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Revised: 12/18/2015] [Accepted: 01/11/2016] [Indexed: 12/20/2022]
Abstract
Understanding the complex process by which the invasive form of the Plasmodium falciparum parasite, the merozoite, attaches to and invades erythrocytes as part of its blood stage life cycle represents a key area of research in the battle to combat malaria. Central to this are efforts to determine the identity of receptors on the host cell surface, their corresponding merozoite-binding proteins and the functional relevance of these binding events as part of the invasion process. This review will provide an updated summary of studies identifying receptor interactions essential for or implicated in P. falciparum merozoite invasion of human erythrocytes, highlighting the recent identification of new receptors using groundbreaking high throughput approaches and with particular focus on the properties and putative involvement of the erythrocyte proteins targeted by these invasion pathways.
Collapse
Affiliation(s)
- T J Satchwell
- School of Biochemistry, Biomedical Sciences Building, University Walk, Bristol, UK
| |
Collapse
|
91
|
Abstract
There have been significant decreases in malaria mortality and morbidity in the last 10-15 years, and the most advanced pre-erythrocytic malaria vaccine, RTS,S, received a positive opinion from European regulators in July 2015. However, no blood-stage vaccine has reached a phase III trial. The first part of this review summarizes the pros and cons of various assays and models that have been and will be used to predict the efficacy of blood-stage vaccines. In the second part, blood-stage vaccine candidates that showed some efficacy in human clinical trials or controlled human malaria infection models are discussed. Then, candidates under clinical investigation are described in the third part, and other novel candidates and strategies are reviewed in the last part.
Collapse
Affiliation(s)
- Kazutoyo Miura
- a Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases , National Institutes of Health , Rockville , MD , USA
| |
Collapse
|
92
|
Zhu X, Zhao Z, Feng Y, Li P, Liu F, Liu J, Yang Z, Yan G, Fan Q, Cao Y, Cui L. Genetic diversity of the Plasmodium falciparum apical membrane antigen I gene in parasite population from the China-Myanmar border area. INFECTION GENETICS AND EVOLUTION 2016; 39:155-162. [PMID: 26825252 DOI: 10.1016/j.meegid.2016.01.021] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Revised: 01/20/2016] [Accepted: 01/23/2016] [Indexed: 11/28/2022]
Abstract
To investigate the genetic diversity of the Plasmodium falciparum apical membrane antigen 1 (PfAMA1) gene in Southeast Asia, we determined PfAMA1 sequences from 135 field isolates collected from the China-Myanmar border area and compared them with 956 publically available PfAMA1 sequences from seven global P. falciparum populations. This analysis revealed high genetic diversity of PfAMA1 in global P. falciparum populations with a total of 229 haplotypes identified. The genetic diversity of PfAMA1 gene from the China-Myanmar border is not evenly distributed in the different domains of this gene. Sequence diversity in PfAMA1 from the China-Myanmar border is lower than that observed in Thai, African and Oceanian populations, but higher than that in the South American population. This appeared to correlate well with the levels of endemicity of different malaria-endemic regions, where hyperendemic regions favor genetic cross of the parasite isolates and generation of higher genetic diversity. Neutrality tests show significant departure from neutrality in the entire ectodomain and Domain I of PfAMA1 in the China-Myanmar border parasite population. We found evidence supporting a substantial continent-wise genetic structure among P. falciparum populations, with the highest genetic differentiation detected between the China-Myanmar border and the South American populations. Whereas no alleles were unique to a specific region, there were considerable geographical differences in major alleles and their frequencies, highlighting further necessity to include more PfAMA1 alleles in vaccine designs.
Collapse
Affiliation(s)
- Xiaotong Zhu
- Department of Immunology, College of Basic Medical Science, China Medical University, Shenyang, Liaoning 110122, China
| | - Zhenjun Zhao
- Dalian Institute of Biotechnology, Dalian, Liaoning, China
| | - Yonghui Feng
- Department of Laboratory Medicine, The First Hospital of China Medical University, Shenyang, Liaoning 110001, China
| | - Peipei Li
- Dalian Institute of Biotechnology, Dalian, Liaoning, China
| | - Fei Liu
- Department of Immunology, College of Basic Medical Science, China Medical University, Shenyang, Liaoning 110122, China
| | - Jun Liu
- Department of Immunology, College of Basic Medical Science, China Medical University, Shenyang, Liaoning 110122, China
| | - Zhaoqing Yang
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Guiyun Yan
- Program in Public Health, University of California, Irvine, CA, USA
| | - Qi Fan
- Dalian Institute of Biotechnology, Dalian, Liaoning, China
| | - Yaming Cao
- Department of Immunology, College of Basic Medical Science, China Medical University, Shenyang, Liaoning 110122, China.
| | - Liwang Cui
- Department of Immunology, College of Basic Medical Science, China Medical University, Shenyang, Liaoning 110122, China; Department of Entomology, The Pennsylvania State University, University Park, PA 16802, USA.
| |
Collapse
|
93
|
Krishnarjuna B, Lim SS, Devine SM, Debono CO, Lam R, Chandrashekaran IR, Jaipuria G, Yagi H, Atreya HS, Scanlon MJ, MacRaild CA, Scammells PJ, Norton RS. Solution NMR characterization of apical membrane antigen 1 and small molecule interactions as a basis for designing new antimalarials. J Mol Recognit 2016; 29:281-91. [DOI: 10.1002/jmr.2529] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Accepted: 11/28/2015] [Indexed: 01/12/2023]
Affiliation(s)
- Bankala Krishnarjuna
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences; Monash University; 381 Royal Parade Parkville Victoria 3052 Australia
| | - San Sui Lim
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences; Monash University; 381 Royal Parade Parkville Victoria 3052 Australia
| | - Shane M. Devine
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences; Monash University; 381 Royal Parade Parkville Victoria 3052 Australia
| | - Cael O. Debono
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences; Monash University; 381 Royal Parade Parkville Victoria 3052 Australia
| | - Raymond Lam
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences; Monash University; 381 Royal Parade Parkville Victoria 3052 Australia
| | - Indu R. Chandrashekaran
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences; Monash University; 381 Royal Parade Parkville Victoria 3052 Australia
| | - Garima Jaipuria
- NMR Research Centre; Indian Institute of Science; Bangalore 560012 India
| | - Hiromasa Yagi
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences; Monash University; 381 Royal Parade Parkville Victoria 3052 Australia
| | | | - Martin J. Scanlon
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences; Monash University; 381 Royal Parade Parkville Victoria 3052 Australia
| | - Christopher A. MacRaild
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences; Monash University; 381 Royal Parade Parkville Victoria 3052 Australia
| | - Peter J. Scammells
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences; Monash University; 381 Royal Parade Parkville Victoria 3052 Australia
| | - Raymond S. Norton
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences; Monash University; 381 Royal Parade Parkville Victoria 3052 Australia
| |
Collapse
|
94
|
Koch M, Baum J. The mechanics of malaria parasite invasion of the human erythrocyte - towards a reassessment of the host cell contribution. Cell Microbiol 2016; 18:319-29. [PMID: 26663815 PMCID: PMC4819681 DOI: 10.1111/cmi.12557] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2015] [Revised: 11/30/2015] [Accepted: 12/07/2015] [Indexed: 01/15/2023]
Abstract
Despite decades of research, we still know little about the mechanics of Plasmodium host cell invasion. Fundamentally, while the essential or non‐essential nature of different parasite proteins is becoming clearer, their actual function and how each comes together to govern invasion are poorly understood. Furthermore, in recent years an emerging world view is shifting focus away from the parasite actin–myosin motor being the sole force responsible for entry to an appreciation of host cell dynamics and forces and their contribution to the process. In this review, we discuss merozoite invasion of the erythrocyte, focusing on the complex set of pre‐invasion events and how these might prime the red cell to facilitate invasion. While traditionally parasite interactions at this stage have been viewed simplistically as mediating adhesion only, recent work makes it apparent that by interacting with a number of host receptors and signalling pathways, combined with secretion of parasite‐derived lipid material, that the merozoite may initiate cytoskeletal re‐arrangements and biophysical changes in the erythrocyte that greatly reduce energy barriers for entry. Seen in this light Plasmodium invasion may well turn out to be a balance between host and parasite forces, much like that of other pathogen infection mechanisms.
Collapse
Affiliation(s)
- Marion Koch
- Department of Life Sciences, Imperial College London, Sir Alexander Fleming Building, Exhibition Road, South Kensington, London, SW7 2AZ, UK
| | - Jake Baum
- Department of Life Sciences, Imperial College London, Sir Alexander Fleming Building, Exhibition Road, South Kensington, London, SW7 2AZ, UK
| |
Collapse
|
95
|
Riglar DT, Whitehead L, Cowman AF, Rogers KL, Baum J. Localisation-based imaging of malarial antigens during erythrocyte entry reaffirms a role for AMA1 but not MTRAP in invasion. J Cell Sci 2015; 129:228-42. [PMID: 26604223 PMCID: PMC4732298 DOI: 10.1242/jcs.177741] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Accepted: 11/16/2015] [Indexed: 01/17/2023] Open
Abstract
Microscopy-based localisation of proteins during malaria parasite (Plasmodium) invasion of the erythrocyte is widely used for tentative assignment of protein function. To date, however, imaging has been limited by the rarity of invasion events and the poor resolution available, given the micron size of the parasite, which leads to a lack of quantitative measures for definitive localisation. Here, using computational image analysis we have attempted to assign relative protein localisation during invasion using wide-field deconvolution microscopy. By incorporating three-dimensional information we present a detailed assessment of known parasite effectors predicted to function during entry but as yet untested or for which data are equivocal. Our method, termed longitudinal intensity profiling, resolves confusion surrounding the localisation of apical membrane antigen 1 (AMA1) at the merozoite–erythrocyte junction and predicts that the merozoite thrombospondin-related anonymous protein (MTRAP) is unlikely to play a direct role in the mechanics of entry, an observation supported with additional biochemical evidence. This approach sets a benchmark for imaging of complex micron-scale events and cautions against simplistic interpretations of small numbers of representative images for the assignment of protein function or prioritisation of candidates as therapeutic targets. Highlighted Article: Here we develop a high-definition imaging approach to dissect and assign function to proteins involved in the rapid process of malaria parasite invasion of the human erythrocyte.
Collapse
Affiliation(s)
- David T Riglar
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, 3052, Australia Department of Medical Biology, University of Melbourne, Victoria, 3050, Melbourne, Australia
| | - Lachlan Whitehead
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, 3052, Australia Department of Medical Biology, University of Melbourne, Victoria, 3050, Melbourne, Australia
| | - Alan F Cowman
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, 3052, Australia Department of Medical Biology, University of Melbourne, Victoria, 3050, Melbourne, Australia
| | - Kelly L Rogers
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, 3052, Australia Department of Medical Biology, University of Melbourne, Victoria, 3050, Melbourne, Australia
| | - Jake Baum
- Department of Life Sciences, Imperial College, London SW7 2AZ, UK
| |
Collapse
|
96
|
Olshina MA, Angrisano F, Marapana DS, Riglar DT, Bane K, Wong W, Catimel B, Yin MX, Holmes AB, Frischknecht F, Kovar DR, Baum J. Plasmodium falciparum coronin organizes arrays of parallel actin filaments potentially guiding directional motility in invasive malaria parasites. Malar J 2015; 14:280. [PMID: 26187846 PMCID: PMC4506582 DOI: 10.1186/s12936-015-0801-5] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Accepted: 07/04/2015] [Indexed: 12/20/2022] Open
Abstract
Background Gliding motility in Plasmodium parasites, the aetiological agents of malaria disease, is mediated by
an actomyosin motor anchored in the outer pellicle of the motile cell. Effective motility is dependent on a parasite myosin motor and turnover of dynamic parasite actin filaments. To date, however, the basis for directional motility is not known. Whilst myosin is very likely orientated as a result of its anchorage within the parasite, how actin filaments are orientated to facilitate directional force generation remains unexplained. In addition, recent evidence has questioned the linkage between actin filaments and secreted surface antigens leaving the way by which motor force is transmitted to the extracellular milieu unknown. Malaria parasites possess a markedly reduced repertoire of actin regulators, among which few are predicted to interact with filamentous (F)-actin directly. One of these, PF3D7_1251200, shows strong homology to the coronin family of actin-filament binding proteins, herein referred to as PfCoronin. Methods Here the N terminal beta propeller domain of PfCoronin (PfCor-N) was expressed to assess its ability to bind and bundle pre-formed actin filaments by sedimentation assay, total internal reflection fluorescence (TIRF) microscopy and confocal imaging as well as to explore its ability to bind phospholipids. In parallel a tagged PfCoronin line in Plasmodium falciparum was generated to determine the cellular localization of the protein during asexual parasite development and blood-stage merozoite invasion. Results A combination of biochemical approaches demonstrated that the N-terminal beta-propeller domain of PfCoronin is capable of binding F-actin and facilitating formation of parallel filament bundles. In parasites, PfCoronin is expressed late in the asexual lifecycle and localizes to the pellicle region of invasive merozoites before and during erythrocyte entry. PfCoronin also associates strongly with membranes within the cell, likely mediated by interactions with phosphatidylinositol-4,5-bisphosphate (PI(4,5)P2) at the plasma membrane. Conclusions These data suggest PfCoronin may fulfil a key role as the critical determinant of actin filament organization in the Plasmodium cell. This raises the possibility that macro-molecular organization of actin mediates directional motility in gliding parasites. Electronic supplementary material The online version of this article (doi:10.1186/s12936-015-0801-5) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Maya A Olshina
- Infection and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, 3052, Australia. .,Department of Medical Biology, University of Melbourne, Parkville, VIC, 3052, Australia.
| | - Fiona Angrisano
- Infection and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, 3052, Australia. .,Department of Medical Biology, University of Melbourne, Parkville, VIC, 3052, Australia.
| | - Danushka S Marapana
- Infection and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, 3052, Australia. .,Department of Medical Biology, University of Melbourne, Parkville, VIC, 3052, Australia.
| | - David T Riglar
- Infection and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, 3052, Australia. .,Department of Medical Biology, University of Melbourne, Parkville, VIC, 3052, Australia. .,Department of Systems Biology, Harvard Medical School, 200 Longwood Ave WAB 536, Boston, MA, 02115, USA.
| | - Kartik Bane
- Department of Infectious Diseases, University of Heidelberg Medical School, Heidelberg, Germany.
| | - Wilson Wong
- Infection and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, 3052, Australia. .,Department of Medical Biology, University of Melbourne, Parkville, VIC, 3052, Australia.
| | - Bruno Catimel
- Ludwig Institute for Cancer Research, Melbourne Tumour Biology Branch, Royal Melbourne Hospital, Parkville, VIC, 3052, Australia. .,Systems Biology and Personalised Medicine Division, Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, 3052, Australia.
| | - Meng-Xin Yin
- School of Chemistry, Bio21 Institute, University of Melbourne, Parkville, VIC, 3010, Australia.
| | - Andrew B Holmes
- School of Chemistry, Bio21 Institute, University of Melbourne, Parkville, VIC, 3010, Australia.
| | - Friedrich Frischknecht
- Department of Infectious Diseases, University of Heidelberg Medical School, Heidelberg, Germany.
| | - David R Kovar
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, USA. .,Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, USA.
| | - Jake Baum
- Infection and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, 3052, Australia. .,Department of Medical Biology, University of Melbourne, Parkville, VIC, 3052, Australia. .,Department of Life Sciences, Imperial College London, Sir Alexander Fleming Building, Level 6, South Kensington, London, SW72AZ, UK.
| |
Collapse
|
97
|
Crossey E, Frietze K, Narum DL, Peabody DS, Chackerian B. Identification of an Immunogenic Mimic of a Conserved Epitope on the Plasmodium falciparum Blood Stage Antigen AMA1 Using Virus-Like Particle (VLP) Peptide Display. PLoS One 2015; 10:e0132560. [PMID: 26147502 PMCID: PMC4493041 DOI: 10.1371/journal.pone.0132560] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Accepted: 06/16/2015] [Indexed: 12/22/2022] Open
Abstract
We have developed a peptide display platform based on VLPs of the RNA bacteriophage MS2 that combines the high immunogenicity of VLP display with affinity selection capabilities. Random peptides can be displayed on the VLP surface by genetically inserting sequences into a surface-exposed loop of the viral coat protein. VLP-displayed peptides can then be isolated by selection using antibodies, and the VLP selectants can then be used directly as immunogens. Here, we investigated the ability of this platform to identify mimotopes of a highly conserved conformational epitope present on the Plasmodium falciparum blood-stage protein AMA1. Using 4G2, a monoclonal antibody that binds to this epitope and is a potent inhibitor of erythrocyte invasion, we screened three different VLP-peptide libraries and identified specific VLPs that bound strongly to the selecting mAb. We then tested the ability of a handful of selected VLPs to elicit anti-AMA1 antibody responses in mice. Most of the selected VLPs failed to reliably elicit AMA1 specific antibodies. However, one VLP consistently induced antibodies that cross-reacted with AMA1. Surprisingly, this VLP bound to 4G2 more weakly than the other selectants we identified. Taken together, these data demonstrate that VLP-peptide display can identify immunogenic mimics of a complex conformational epitope and illustrate the promise and challenges of this approach.
Collapse
MESH Headings
- Amino Acid Sequence
- Animals
- Antibodies, Monoclonal/immunology
- Antibodies, Protozoan/immunology
- Antibody Affinity
- Antigen-Antibody Reactions
- Antigens, Protozoan/chemistry
- Antigens, Protozoan/immunology
- Antigens, Surface/chemistry
- Antigens, Surface/immunology
- Chromatography, Gel
- Cross Reactions
- Dimerization
- Enzyme-Linked Immunosorbent Assay
- Epitopes/chemistry
- Epitopes/immunology
- Levivirus
- Malaria Vaccines/immunology
- Membrane Proteins/chemistry
- Membrane Proteins/immunology
- Mice
- Mice, Inbred BALB C
- Models, Molecular
- Molecular Sequence Data
- Mutagenesis, Site-Directed
- Peptide Library
- Peptides/chemistry
- Peptides/immunology
- Plasmodium falciparum/immunology
- Protein Conformation
- Protozoan Proteins/chemistry
- Protozoan Proteins/immunology
- Sequence Analysis, Protein
- Vaccines, Virus-Like Particle/immunology
Collapse
Affiliation(s)
- Erin Crossey
- Department of Molecular Genetics and Microbiology, University of New Mexico, Albuquerque, NM 87131, United States of America
| | - Kathryn Frietze
- Department of Molecular Genetics and Microbiology, University of New Mexico, Albuquerque, NM 87131, United States of America
| | - David L. Narum
- Laboratory of Malaria Immunology and Vaccinology, National Institutes of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, United States of America
| | - David S. Peabody
- Department of Molecular Genetics and Microbiology, University of New Mexico, Albuquerque, NM 87131, United States of America
| | - Bryce Chackerian
- Department of Molecular Genetics and Microbiology, University of New Mexico, Albuquerque, NM 87131, United States of America
- * E-mail:
| |
Collapse
|
98
|
Josling G, Petter M, Oehring S, Gupta A, Dietz O, Wilson D, Schubert T, Längst G, Gilson P, Crabb B, Moes S, Jenoe P, Lim S, Brown G, Bozdech Z, Voss T, Duffy M. A Plasmodium Falciparum Bromodomain Protein Regulates Invasion Gene Expression. Cell Host Microbe 2015; 17:741-51. [DOI: 10.1016/j.chom.2015.05.009] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Revised: 03/30/2015] [Accepted: 05/14/2015] [Indexed: 11/27/2022]
|
99
|
Boucher LE, Bosch J. The apicomplexan glideosome and adhesins - Structures and function. J Struct Biol 2015; 190:93-114. [PMID: 25764948 PMCID: PMC4417069 DOI: 10.1016/j.jsb.2015.02.008] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2014] [Revised: 02/20/2015] [Accepted: 02/26/2015] [Indexed: 01/10/2023]
Abstract
The apicomplexan family of pathogens, which includes Plasmodium spp. and Toxoplasma gondii, are primarily obligate intracellular parasites and invade multiple cell types. These parasites express extracellular membrane protein receptors, adhesins, to form specific pathogen-host cell interaction complexes. Various adhesins are used to invade a variety of cell types. The receptors are linked to an actomyosin motor, which is part of a complex comprised of many proteins known as the invasion machinery or glideosome. To date, reviews on invasion have focused primarily on the molecular pathways and signals of invasion, with little or no structural information presented. Over 75 structures of parasite receptors and glideosome proteins have been deposited with the Protein Data Bank. These structures include adhesins, motor proteins, bridging proteins, inner membrane complex and cytoskeletal proteins, as well as co-crystal structures with peptides and antibodies. These structures provide information regarding key interactions necessary for target receptor engagement, machinery complex formation, how force is transmitted, and the basis of inhibitory antibodies. Additionally, these structures can provide starting points for the development of antibodies and inhibitory molecules targeting protein-protein interactions, with the aim to inhibit invasion. This review provides an overview of the parasite adhesin protein families, the glideosome components, glideosome architecture, and discuss recent work regarding alternative models.
Collapse
Affiliation(s)
- Lauren E Boucher
- Department of Biochemistry and Molecular Biology, Johns Hopkins Bloomberg School of Public Health, 615 N Wolfe St, Baltimore, MD 21205, USA; Johns Hopkins Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, 615 N Wolfe St, Baltimore, MD 21205, USA.
| | - Jürgen Bosch
- Department of Biochemistry and Molecular Biology, Johns Hopkins Bloomberg School of Public Health, 615 N Wolfe St, Baltimore, MD 21205, USA; Johns Hopkins Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, 615 N Wolfe St, Baltimore, MD 21205, USA.
| |
Collapse
|
100
|
Pihan E, Delgadillo RF, Tonkin ML, Pugnière M, Lebrun M, Boulanger MJ, Douguet D. Computational and biophysical approaches to protein-protein interaction inhibition of Plasmodium falciparum AMA1/RON2 complex. J Comput Aided Mol Des 2015; 29:525-39. [PMID: 25822046 DOI: 10.1007/s10822-015-9842-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Accepted: 03/25/2015] [Indexed: 11/30/2022]
Abstract
Invasion of the red blood cell by Plasmodium falciparum parasites requires formation of an electron dense circumferential ring called the Moving Junction (MJ). The MJ is anchored by a high affinity complex of two parasite proteins: Apical Membrane Antigen 1 (PfAMA1) displayed on the surface of the parasite and Rhoptry Neck Protein 2 that is discharged from the parasite and imbedded in the membrane of the host cell. Structural studies of PfAMA1 revealed a conserved hydrophobic groove localized to the apical surface that coordinates RON2 and invasion inhibitory peptides. In the present work, we employed computational and biophysical methods to identify competitive P. falciparum AMA1-RON2 inhibitors with the goal of exploring the 'druggability' of this attractive antimalarial target. A virtual screen followed by molecular docking with the PfAMA1 crystal structure was performed using an eight million compound collection that included commercial molecules, the ChEMBL malaria library and approved drugs. The consensus approach resulted in the selection of inhibitor candidates. We also developed a fluorescence anisotropy assay using a modified inhibitory peptide to experimentally validate the ability of the selected compounds to inhibit the AMA1-RON2 interaction. Among those, we identified one compound that displayed significant inhibition. This study offers interesting clues to improve the throughput and reliability of screening for new drug leads.
Collapse
Affiliation(s)
- Emilie Pihan
- Institut de Pharmacologie Moléculaire et Cellulaire, Université de Nice Sophia-Antipolis, CNRS, UMR 7275, 660, Route des Lucioles, Sophia Antipolis, 06560, Valbonne, France
| | | | | | | | | | | | | |
Collapse
|