1
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Tewey MA, Coulibaly D, Lawton JG, Stucke EM, Zhou AE, Berry AA, Bailey JA, Pike A, Dara A, Ouattara A, Lyke KE, Ifeonu O, Laurens MB, Adams M, Takala-Harrison S, Niangaly A, Kouriba B, Koné AK, Rowe JA, Doumbo OK, Patel JJ, Tan JC, Felgner PL, Plowe CV, Thera MA, Travassos MA. Natural immunity to malaria preferentially targets the endothelial protein C receptor-binding regions of PfEMP1s. mSphere 2023; 8:e0045123. [PMID: 37791774 PMCID: PMC10597466 DOI: 10.1128/msphere.00451-23] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Accepted: 08/21/2023] [Indexed: 10/05/2023] Open
Abstract
Antibody responses to variant surface antigens (VSAs) produced by the malaria parasite Plasmodium falciparum may contribute to age-related natural immunity to severe malaria. One VSA family, P. falciparum erythrocyte membrane protein-1 (PfEMP1), includes a subset of proteins that binds endothelial protein C receptor (EPCR) in human hosts and potentially disrupts the regulation of inflammatory responses, which may lead to the development of severe malaria. We probed peptide microarrays containing segments spanning five PfEMP1 EPCR-binding domain variants with sera from 10 Malian adults and 10 children to determine the differences between adult and pediatric immune responses. We defined serorecognized peptides and amino acid residues as those that elicited a significantly higher antibody response than malaria-naïve controls. We aimed to identify regions consistently serorecognized among adults but not among children across PfEMP1 variants, potentially indicating regions that drive the development of immunity to severe malaria. Adult sera consistently demonstrated broader and more intense serologic responses to constitutive PfEMP1 peptides than pediatric sera, including peptides in EPCR-binding domains. Both adults and children serorecognized a significantly higher proportion of EPCR-binding peptides than peptides that do not directly participate in receptor binding, indicating a preferential development of serologic responses at functional residues. Over the course of a single malaria transmission season, pediatric serological responses increased between the start and the peak of the season, but waned as the transmission season ended. IMPORTANCE Severe malaria and death related to malaria disproportionately affect sub-Saharan children under 5 years of age, commonly manifesting as cerebral malaria and/or severe malarial anemia. In contrast, adults in malaria-endemic regions tend to experience asymptomatic or mild disease. Our findings indicate that natural immunity to malaria targets specific regions within the EPCR-binding domain, particularly peptides containing EPCR-binding residues. Epitopes containing these residues may be promising targets for vaccines or therapeutics directed against severe malaria. Our approach provides insight into the development of natural immunity to a binding target linked to severe malaria by characterizing an "adult-like" response as recognizing a proportion of epitopes within the PfEMP1 protein, particularly regions that mediate EPCR binding. This "adult-like" response likely requires multiple years of malaria exposure, as increases in pediatric serologic response over a single malaria transmission season do not appear significant.
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Affiliation(s)
- Madison A. Tewey
- Malaria Research Program, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Drissa Coulibaly
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Jonathan G. Lawton
- Malaria Research Program, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Emily M. Stucke
- Malaria Research Program, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Albert E. Zhou
- Malaria Research Program, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Andrea A. Berry
- Malaria Research Program, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Jason A. Bailey
- Malaria Research Program, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Andrew Pike
- Malaria Research Program, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Antoine Dara
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Amed Ouattara
- Malaria Research Program, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Kirsten E. Lyke
- Malaria Research Program, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Olukemi Ifeonu
- Malaria Research Program, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Matthew B. Laurens
- Malaria Research Program, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Matthew Adams
- Malaria Research Program, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Shannon Takala-Harrison
- Malaria Research Program, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Amadou Niangaly
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Bourema Kouriba
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Abdoulaye K. Koné
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - J. Alexandra Rowe
- Centre for Immunity, Infection and Evolution, Institute of Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Ogobara K. Doumbo
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | | | - John C. Tan
- Roche NimbleGen, Inc., Madison, Wisconsin, USA
| | - Philip L. Felgner
- Division of Infectious Diseases, Department of Medicine, University of California, Irvine, California, USA
| | - Christopher V. Plowe
- Malaria Research Program, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Mahamadou A. Thera
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Mark A. Travassos
- Malaria Research Program, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
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2
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Wiser MF. Knobs, Adhesion, and Severe Falciparum Malaria. Trop Med Infect Dis 2023; 8:353. [PMID: 37505649 PMCID: PMC10385726 DOI: 10.3390/tropicalmed8070353] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 06/30/2023] [Accepted: 07/02/2023] [Indexed: 07/29/2023] Open
Abstract
Plasmodium falciparum can cause a severe disease with high mortality. A major factor contributing to the increased virulence of P. falciparum, as compared to other human malarial parasites, is the sequestration of infected erythrocytes in the capillary beds of organs and tissues. This sequestration is due to the cytoadherence of infected erythrocytes to endothelial cells. Cytoadherence is primarily mediated by a parasite protein expressed on the surface of the infected erythrocyte called P. falciparum erythrocyte membrane protein-1 (PfEMP1). PfEMP1 is embedded in electron-dense protuberances on the surface of the infected erythrocytes called knobs. These knobs are assembled on the erythrocyte membrane via exported parasite proteins, and the knobs function as focal points for the cytoadherence of infected erythrocytes to endothelial cells. PfEMP1 is a member of the var gene family, and there are approximately 60 antigenically distinct PfEMP1 alleles per parasite genome. Var gene expression exhibits allelic exclusion, with only a single allele being expressed by an individual parasite. This results in sequential waves of antigenically distinct infected erythrocytes and this antigenic variation allows the parasite to establish long-term chronic infections. A wide range of endothelial cell receptors can bind to the various PfEMP1 alleles, and thus, antigenic variation also results in a change in the cytoadherence phenotype. The cytoadherence phenotype may result in infected erythrocytes sequestering in different tissues and this difference in sequestration may explain the wide range of possible clinical manifestations associated with severe falciparum malaria.
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Affiliation(s)
- Mark F Wiser
- Department of Tropical Medicine and Infectious Disease, Tulane University School of Public Health and Tropical Medicine, 1440 Canal Street, New Orleans, LA 70112, USA
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3
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Shakya B, Kilili GK, Wang L, Nakayasu ES, LaCount DJ. Identification of Exported Plasmodium falciparum Proteins That Bind to the Erythrocyte Cytoskeleton. Microorganisms 2022; 10:1438. [PMID: 35889157 PMCID: PMC9320996 DOI: 10.3390/microorganisms10071438] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 07/11/2022] [Accepted: 07/13/2022] [Indexed: 11/28/2022] Open
Abstract
Plasmodium proteins are exported to the erythrocyte cytoplasm to create an environment that supports parasite replication. Although hundreds of proteins are predicted to be exported through Plasmodium export element (PEXEL)-dependent and -independent mechanisms, the functions of exported proteins are largely uncharacterized. In this study, we used a biochemical screening approach to identify putative exported P. falciparum proteins that bound to inside-out vesicles prepared from erythrocytes. Out of 69 P. falciparum PEXEL-motif proteins tested, 18 bound to inside-out vesicles (IOVs) in two or more independent assays. Using co-affinity purifications followed by mass spectrometry, pairwise co-purification experiments, and the split-luciferase assay, we identified 31 putative protein-protein interactions between erythrocyte cytoskeletal proteins and predicted exported P. falciparum proteins. We further showed that PF3D7_1401600 binds to the spectrin-binding domain of erythrocyte ankyrin via its MESA erythrocyte cytoskeleton binding (MEC) motif and to the N-terminal domains of ankyrin and 4.1R through a fragment that required an intact Plasmodium helical interspersed sub-telomeric (PHIST) domain. Introduction of PF3D7_1401600 into erythrocyte ghosts increased retention in the microsphiltration assay, consistent with previous data that reported a reduction of rigidity in red blood cells infected with PF3D7_1401600-deficient parasites.
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Affiliation(s)
- Bikash Shakya
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN 47907, USA; (B.S.); (G.K.K.); (L.W.)
| | - Geoffrey Kimiti Kilili
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN 47907, USA; (B.S.); (G.K.K.); (L.W.)
| | - Ling Wang
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN 47907, USA; (B.S.); (G.K.K.); (L.W.)
| | - Ernesto S. Nakayasu
- Bindley Bioscience Center, Purdue University, West Lafayette, IN 47907, USA;
- Pacific Northwest National Laboratory, Biological Sciences Division, Richland, WA 99352, USA
| | - Douglas J. LaCount
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN 47907, USA; (B.S.); (G.K.K.); (L.W.)
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4
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M’Bana V, Lahree A, Marques S, Slavic K, Mota MM. Plasmodium parasitophorous vacuole membrane-resident protein UIS4 manipulates host cell actin to avoid parasite elimination. iScience 2022; 25:104281. [PMID: 35573190 PMCID: PMC9095750 DOI: 10.1016/j.isci.2022.104281] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 01/09/2022] [Accepted: 04/19/2022] [Indexed: 11/26/2022] Open
Abstract
Parasite-derived PVM-resident proteins are critical for complete parasite development inside hepatocytes, although the function of most of these proteins remains unknown. Here, we show that the upregulated in infectious sporozoites 4 (UIS4) protein, resident at the PVM, interacts with the host cell actin. By suppressing filamentous actin formation, UIS4 avoids parasite elimination. Host cell actin dynamics increases around UIS4-deficient parasites, which is associated with subsequent parasite elimination. Notably, parasite elimination is impaired significantly by the inhibition of host myosin-II, possibly through relieving the compression generated by actomyosin complexes at the host-parasite interface. Together, these data reveal that UIS4 has a critical role in the evasion of host defensive mechanisms, enabling hence EEF survival and development. Plasmodium PVM-resident protein UIS4 interacts with host cell actin Host actin dynamics is altered around exoerythocytic forms (EEFs) lacking UIS4 Actin activity around EEFs lacking UIS4 is associated with parasite elimination Parasite elimination depends on actomyosin complexes formed around the PVM
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5
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Jäger J, Patra P, Sanchez CP, Lanzer M, Schwarz US. A particle-based computational model to analyse remodelling of the red blood cell cytoskeleton during malaria infections. PLoS Comput Biol 2022; 18:e1009509. [PMID: 35394995 PMCID: PMC9020725 DOI: 10.1371/journal.pcbi.1009509] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 04/20/2022] [Accepted: 03/21/2022] [Indexed: 11/18/2022] Open
Abstract
Red blood cells can withstand the harsh mechanical conditions in the vasculature only because the bending rigidity of their plasma membrane is complemented by the shear elasticity of the underlying spectrin-actin network. During an infection by the malaria parasite Plasmodium falciparum, the parasite mines host actin from the junctional complexes and establishes a system of adhesive knobs, whose main structural component is the knob-associated histidine rich protein (KAHRP) secreted by the parasite. Here we aim at a mechanistic understanding of this dramatic transformation process. We have developed a particle-based computational model for the cytoskeleton of red blood cells and simulated it with Brownian dynamics to predict the mechanical changes resulting from actin mining and KAHRP-clustering. Our simulations include the three-dimensional conformations of the semi-flexible spectrin chains, the capping of the actin protofilaments and several established binding sites for KAHRP. For the healthy red blood cell, we find that incorporation of actin protofilaments leads to two regimes in the shear response. Actin mining decreases the shear modulus, but knob formation increases it. We show that dynamical changes in KAHRP binding affinities can explain the experimentally observed relocalization of KAHRP from ankyrin to actin complexes and demonstrate good qualitative agreement with experiments by measuring pair cross-correlations both in the computer simulations and in super-resolution imaging experiments. Malaria is one of the deadliest infectious diseases and its symptoms are related to the blood stage, when the parasite multiplies within red blood cells. In order to avoid clearance by the spleen, the parasite produces specific factors like the adhesion receptor PfEMP1 and the multifunctional protein KAHRP that lead to the formation of adhesive knobs on the surface of the red blood cells and thus increase residence time in the vasculature. We have developed a computational model for the parasite-induced remodelling of the actin-spectrin network to quantitatively predict the dynamical changes in the mechanical properties of the infected red blood cells and the spatial distribution of the different protein components of the membrane skeleton. Our simulations show that KAHRP can relocate to actin junctions due to dynamical changes in binding affinities, in good qualitative agreement with super-resolution imaging experiments. In the future, our simulation framework can be used to gain further mechanistic insight into the way malaria parasites attack the red blood cell cytoskeleton.
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Affiliation(s)
- Julia Jäger
- Institute for Theoretical Physics, Heidelberg University, Heidelberg, Germany
- BioQuant-Center for Quantitative Biology, Heidelberg University, Heidelberg, Germany
| | - Pintu Patra
- Institute for Theoretical Physics, Heidelberg University, Heidelberg, Germany
- BioQuant-Center for Quantitative Biology, Heidelberg University, Heidelberg, Germany
| | - Cecilia P. Sanchez
- Center of Infectious Diseases, Parasitology, University Hospital Heidelberg, Heidelberg, Germany
| | - Michael Lanzer
- Center of Infectious Diseases, Parasitology, University Hospital Heidelberg, Heidelberg, Germany
- * E-mail: (ML); (USS)
| | - Ulrich S. Schwarz
- Institute for Theoretical Physics, Heidelberg University, Heidelberg, Germany
- BioQuant-Center for Quantitative Biology, Heidelberg University, Heidelberg, Germany
- * E-mail: (ML); (USS)
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6
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Sanchez CP, Patra P, Chang SYS, Karathanasis C, Hanebutte L, Kilian N, Cyrklaff M, Heilemann M, Schwarz US, Kudryashev M, Lanzer M. KAHRP dynamically relocalizes to remodeled actin junctions and associates with knob spirals in Plasmodium falciparum-infected erythrocytes. Mol Microbiol 2021; 117:274-292. [PMID: 34514656 DOI: 10.1111/mmi.14811] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 09/06/2021] [Accepted: 09/07/2021] [Indexed: 11/28/2022]
Abstract
The knob-associated histidine-rich protein (KAHRP) plays a pivotal role in the pathophysiology of Plasmodium falciparum malaria by forming membrane protrusions in infected erythrocytes, which anchor parasite-encoded adhesins to the membrane skeleton. The resulting sequestration of parasitized erythrocytes in the microvasculature leads to severe disease. Despite KAHRP being an important virulence factor, its physical location within the membrane skeleton is still debated, as is its function in knob formation. Here, we show by super-resolution microscopy that KAHRP initially associates with various skeletal components, including ankyrin bridges, but eventually colocalizes with remnant actin junctions. We further present a 35 Å map of the spiral scaffold underlying knobs and show that a KAHRP-targeting nanoprobe binds close to the spiral scaffold. Single-molecule localization microscopy detected ~60 KAHRP molecules/knob. We propose a dynamic model of KAHRP organization and a function of KAHRP in attaching other factors to the spiral scaffold.
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Affiliation(s)
- Cecilia P Sanchez
- Center of Infectious Diseases, Parasitology, Universitätsklinikum Heidelberg, Heidelberg, Germany
| | - Pintu Patra
- Institute for Theoretical Physics, Heidelberg University, Heidelberg, Germany.,BioQuant-Center for Quantitative Biology, Heidelberg University, Heidelberg, Germany
| | - Shih-Ying Scott Chang
- Max Planck Institute for Biophysics and Buchmann Institute for Molecular Life Sciences (BMLS), Goethe University of Frankfurt, Frankfurt, Germany
| | - Christos Karathanasis
- Institute for Physical and Theoretical Chemistry, Goethe-University Frankfurt, Frankfurt, Germany
| | - Lukas Hanebutte
- Center of Infectious Diseases, Parasitology, Universitätsklinikum Heidelberg, Heidelberg, Germany
| | - Nicole Kilian
- Center of Infectious Diseases, Parasitology, Universitätsklinikum Heidelberg, Heidelberg, Germany
| | - Marek Cyrklaff
- Center of Infectious Diseases, Parasitology, Universitätsklinikum Heidelberg, Heidelberg, Germany
| | - Mike Heilemann
- BioQuant-Center for Quantitative Biology, Heidelberg University, Heidelberg, Germany.,Institute for Physical and Theoretical Chemistry, Goethe-University Frankfurt, Frankfurt, Germany
| | - Ulrich S Schwarz
- Institute for Theoretical Physics, Heidelberg University, Heidelberg, Germany.,BioQuant-Center for Quantitative Biology, Heidelberg University, Heidelberg, Germany
| | - Mikhail Kudryashev
- Max Planck Institute for Biophysics and Buchmann Institute for Molecular Life Sciences (BMLS), Goethe University of Frankfurt, Frankfurt, Germany
| | - Michael Lanzer
- Center of Infectious Diseases, Parasitology, Universitätsklinikum Heidelberg, Heidelberg, Germany
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7
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Theileria equi claudin like apicomplexan microneme protein contains neutralization-sensitive epitopes and interacts with components of the equine erythrocyte membrane skeleton. Sci Rep 2021; 11:9301. [PMID: 33927329 PMCID: PMC8085155 DOI: 10.1038/s41598-021-88902-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Accepted: 04/16/2021] [Indexed: 11/19/2022] Open
Abstract
Theileria equi is a widely distributed apicomplexan parasite that causes severe hemolytic anemia in equid species. There is currently no effective vaccine for control of the parasite and understanding the mechanism that T. equi utilizes to invade host cells may be crucial for vaccine development. Unlike most apicomplexan species studied to date, the role of micronemes in T. equi invasion of host cells is unknown. We therefore assessed the role of the T. equi claudin-like apicomplexan microneme protein (CLAMP) in the invasion of equine erythrocytes as a first step towards understanding the role of this organelle in the parasite. Our findings show that CLAMP is expressed in the merozoite and intra-erythrocytic developmental stages of T. equi and in vitro neutralization experiments suggest that the protein is involved in erythrocyte invasion. Proteomic analyses indicate that CLAMP interacts with the equine erythrocyte α-and β- spectrin chains in the initial stages of T. equi invasion and maintains these interactions while also associating with the anion-exchange protein, tropomyosin 3, band 4.1 and cytoplasmic actin 1 after invasion. Additionally, serological analyses show that T. equi-infected horses mount robust antibody responses against CLAMP indicating that the protein is immunogenic and therefore represents a potential vaccine candidate.
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8
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Andrade CM, Fleckenstein H, Thomson-Luque R, Doumbo S, Lima NF, Anderson C, Hibbert J, Hopp CS, Tran TM, Li S, Niangaly M, Cisse H, Doumtabe D, Skinner J, Sturdevant D, Ricklefs S, Virtaneva K, Asghar M, Homann MV, Turner L, Martins J, Allman EL, N'Dri ME, Winkler V, Llinás M, Lavazec C, Martens C, Färnert A, Kayentao K, Ongoiba A, Lavstsen T, Osório NS, Otto TD, Recker M, Traore B, Crompton PD, Portugal S. Increased circulation time of Plasmodium falciparum underlies persistent asymptomatic infection in the dry season. Nat Med 2020; 26:1929-1940. [PMID: 33106664 DOI: 10.1038/s41591-020-1084-0] [Citation(s) in RCA: 67] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Accepted: 08/27/2020] [Indexed: 12/25/2022]
Abstract
The dry season is a major challenge for Plasmodium falciparum parasites in many malaria endemic regions, where water availability limits mosquito vectors to only part of the year. How P. falciparum bridges two transmission seasons months apart, without being cleared by the human host or compromising host survival, is poorly understood. Here we show that low levels of P. falciparum parasites persist in the blood of asymptomatic Malian individuals during the 5- to 6-month dry season, rarely causing symptoms and minimally affecting the host immune response. Parasites isolated during the dry season are transcriptionally distinct from those of individuals with febrile malaria in the transmission season, coinciding with longer circulation within each replicative cycle of parasitized erythrocytes without adhering to the vascular endothelium. Low parasite levels during the dry season are not due to impaired replication but rather to increased splenic clearance of longer-circulating infected erythrocytes, which likely maintain parasitemias below clinical and immunological radar. We propose that P. falciparum virulence in areas of seasonal malaria transmission is regulated so that the parasite decreases its endothelial binding capacity, allowing increased splenic clearance and enabling several months of subclinical parasite persistence.
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Affiliation(s)
- Carolina M Andrade
- Center for Infectious Diseases, Parasitology, Heidelberg University Hospital, Heidelberg, Germany
| | - Hannah Fleckenstein
- Center for Infectious Diseases, Parasitology, Heidelberg University Hospital, Heidelberg, Germany
| | - Richard Thomson-Luque
- Center for Infectious Diseases, Parasitology, Heidelberg University Hospital, Heidelberg, Germany
| | - Safiatou Doumbo
- Mali International Center of Excellence in Research, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Nathalia F Lima
- Center for Infectious Diseases, Parasitology, Heidelberg University Hospital, Heidelberg, Germany
| | - Carrie Anderson
- Center for Infectious Diseases, Parasitology, Heidelberg University Hospital, Heidelberg, Germany
| | - Julia Hibbert
- Center for Infectious Diseases, Parasitology, Heidelberg University Hospital, Heidelberg, Germany
| | - Christine S Hopp
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Tuan M Tran
- Division of Infectious Diseases, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Shanping Li
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Moussa Niangaly
- Mali International Center of Excellence in Research, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Hamidou Cisse
- Mali International Center of Excellence in Research, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Didier Doumtabe
- Mali International Center of Excellence in Research, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Jeff Skinner
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Dan Sturdevant
- Rocky Mountain Laboratory Research Technologies Section, Genomics Unit, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT, USA
| | - Stacy Ricklefs
- Rocky Mountain Laboratory Research Technologies Section, Genomics Unit, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT, USA
| | - Kimmo Virtaneva
- Rocky Mountain Laboratory Research Technologies Section, Genomics Unit, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT, USA
| | - Muhammad Asghar
- Department of Medicine Solna, Division of Infectious Diseases, Karolinska Institutet, Stockholm, Sweden.,Department of Infectious Diseases, Karolinska University Hospital, Stockholm, Sweden
| | - Manijeh Vafa Homann
- Department of Medicine Solna, Division of Infectious Diseases, Karolinska Institutet, Stockholm, Sweden.,Department of Infectious Diseases, Karolinska University Hospital, Stockholm, Sweden
| | - Louise Turner
- Department of Immunology and Microbiology, Centre for Medical Parasitology, Faculty of Health and Medical Sciences, University of Copenhagen, København N, Denmark.,Department of Infectious Diseases, Copenhagen University Hospital (Rigshospitalet), Copenhagen, Denmark
| | - Joana Martins
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Portugal and ICVS/3B's -PT Government Associate Laboratory, Braga, Portugal
| | - Erik L Allman
- Department of Biochemistry and Molecular Biology, Huck Center for Malaria Research, The Pennsylvania State University, State College, PA, USA
| | | | - Volker Winkler
- Institute of Global Health, Heidelberg University Hospital, Heidelberg, Germany
| | - Manuel Llinás
- Department of Biochemistry and Molecular Biology, Huck Center for Malaria Research, The Pennsylvania State University, State College, PA, USA.,Department of Chemistry, The Pennsylvania State University, State College, PA, USA
| | | | - Craig Martens
- Rocky Mountain Laboratory Research Technologies Section, Genomics Unit, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT, USA
| | - Anna Färnert
- Department of Medicine Solna, Division of Infectious Diseases, Karolinska Institutet, Stockholm, Sweden.,Department of Infectious Diseases, Karolinska University Hospital, Stockholm, Sweden
| | - Kassoum Kayentao
- Mali International Center of Excellence in Research, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Aissata Ongoiba
- Mali International Center of Excellence in Research, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Thomas Lavstsen
- Department of Immunology and Microbiology, Centre for Medical Parasitology, Faculty of Health and Medical Sciences, University of Copenhagen, København N, Denmark.,Department of Infectious Diseases, Copenhagen University Hospital (Rigshospitalet), Copenhagen, Denmark
| | - Nuno S Osório
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Portugal and ICVS/3B's -PT Government Associate Laboratory, Braga, Portugal
| | - Thomas D Otto
- Institute of Infection, Immunity & Inflammation, MVLS, University of Glasgow, Glasgow, UK
| | - Mario Recker
- Centre for Mathematics & the Environment, University of Exeter, Penryn Campus, Penryn, UK
| | - Boubacar Traore
- Mali International Center of Excellence in Research, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Peter D Crompton
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Silvia Portugal
- Center for Infectious Diseases, Parasitology, Heidelberg University Hospital, Heidelberg, Germany. .,German Center for Infection Research (DZIF), Heidelberg, Heidelberg, Germany. .,Max Planck Institute for Infection Biology, Berlin, Germany.
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9
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Host Cytoskeleton Remodeling throughout the Blood Stages of Plasmodium falciparum. Microbiol Mol Biol Rev 2019; 83:83/4/e00013-19. [PMID: 31484690 DOI: 10.1128/mmbr.00013-19] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The asexual intraerythrocytic development of Plasmodium falciparum, causing the most severe form of human malaria, is marked by extensive host cell remodeling. Throughout the processes of invasion, intracellular development, and egress, the erythrocyte membrane skeleton is remodeled by the parasite as required for each specific developmental stage. The remodeling is facilitated by a plethora of exported parasite proteins, and the erythrocyte membrane skeleton is the interface of most of the observed interactions between the parasite and host cell proteins. Host cell remodeling has been extensively described and there is a vast body of information on protein export or the description of parasite-induced structures such as Maurer's clefts or knobs on the host cell surface. Here we specifically review the molecular level of each host cell-remodeling step at each stage of the intraerythrocytic development of P. falciparum We describe key events, such as invasion, knob formation, and egress, and identify the interactions between exported parasite proteins and the host cell cytoskeleton. We discuss each remodeling step with respect to time and specific requirement of the developing parasite to explain host cell remodeling in a stage-specific manner. Thus, we highlight the interaction with the host membrane skeleton as a key event in parasite survival.
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10
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Takano R, Kozuka-Hata H, Kondoh D, Bochimoto H, Oyama M, Kato K. A High-Resolution Map of SBP1 Interactomes in Plasmodium falciparum-infected Erythrocytes. iScience 2019; 19:703-714. [PMID: 31476617 PMCID: PMC6728614 DOI: 10.1016/j.isci.2019.07.035] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 05/09/2019] [Accepted: 07/19/2019] [Indexed: 11/19/2022] Open
Abstract
The pathogenesis of malaria parasites depends on host erythrocyte modifications that are facilitated by parasite proteins exported to the host cytoplasm. These exported proteins form a trafficking complex in the host cytoplasm that transports virulence determinants to the erythrocyte surface; this complex is thus essential for malaria virulence. Here, we report a comprehensive interaction network map of this complex. We developed authentic, unbiased, highly sensitive proteomic approaches to determine the proteins that interact with a core component of the complex, SBP1 (skeleton-binding protein 1). SBP1 interactomes revealed numerous exported proteins and potential interactors associated with SBP1 intracellular trafficking. We identified several host-parasite protein interactions and linked the exported protein MAL8P1.4 to Plasmodium falciparum virulence in infected erythrocytes. Our study highlights the complicated interplay between parasite and host proteins in the host cytoplasm and provides an interaction dataset connecting dozens of exported proteins required for P. falciparum virulence. We used shotgun proteomics to identify SBP1-interacting factors System validation showed complex interplay between parasite and host proteins Our system can be used to explore protozoan parasite virulence in erythrocytes
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Affiliation(s)
- Ryo Takano
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido 080-8555, Japan
| | - Hiroko Kozuka-Hata
- Medical Proteomics Laboratory, Institute of Medical Science, The University of Tokyo, Minato-ku, Tokyo 108-8639, Japan
| | - Daisuke Kondoh
- Laboratory of Veterinary Anatomy, Department of Basic Veterinary Medicine, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido 080-8555, Japan
| | - Hiroki Bochimoto
- Health Care Administration Center, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido 080-8555, Japan
| | - Masaaki Oyama
- Medical Proteomics Laboratory, Institute of Medical Science, The University of Tokyo, Minato-ku, Tokyo 108-8639, Japan
| | - Kentaro Kato
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido 080-8555, Japan; Laboratory of Sustainable Animal Environment, Graduate School of Agricultural Science, Tohoku University, Naruko-onsen, Osaki, Miyagi 989-6711, Japan.
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11
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Sanchez CP, Karathanasis C, Sanchez R, Cyrklaff M, Jäger J, Buchholz B, Schwarz US, Heilemann M, Lanzer M. Single-molecule imaging and quantification of the immune-variant adhesin VAR2CSA on knobs of Plasmodium falciparum-infected erythrocytes. Commun Biol 2019; 2:172. [PMID: 31098405 PMCID: PMC6506540 DOI: 10.1038/s42003-019-0429-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Accepted: 04/17/2019] [Indexed: 12/16/2022] Open
Abstract
PfEMP1 (erythrocyte membrane protein 1) adhesins play a pivotal role in the pathophysiology of falciparum malaria, by mediating sequestration of Plasmodium falciparum-infected erythrocytes in the microvasculature. PfEMP1 variants are expressed by var genes and are presented on membrane elevations, termed knobs. However, the organization of PfEMP1 on knobs is largely unclear. Here, we use super-resolution microscopy and genetically altered parasites expressing a modified var2csa gene in which the coding sequence of the photoactivatable mEOS2 was inserted to determine the number and distribution of PfEMP1 on single knobs. The data were verified by quantitative fluorescence-activated cell sorting analysis and immuno-electron microscopy together with stereology methods. We show that knobs contain 3.3 ± 1.7 and 4.3 ± 2.5 PfEMP1 molecules, predominantly placed on the knob tip, in parasitized erythrocytes containing wild type and sickle haemoglobin, respectively. The ramifications of our findings for cytoadhesion and immune evasion are discussed.
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Affiliation(s)
- Cecilia P. Sanchez
- Center of Infectious Diseases, Parasitology, Universitätsklinikum Heidelberg, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
| | - Christos Karathanasis
- Institute for Physical and Theoretical Chemistry, Goethe-University Frankfurt, Max-von-Laue-Str. 7, 60438 Frankfurt, Germany
| | - Rodrigo Sanchez
- Center of Infectious Diseases, Parasitology, Universitätsklinikum Heidelberg, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
| | - Marek Cyrklaff
- Center of Infectious Diseases, Parasitology, Universitätsklinikum Heidelberg, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
| | - Julia Jäger
- Institute for Theoretical Physics, Heidelberg University, Philosophenweg 16, 69120 Heidelberg, Germany
| | - Bernd Buchholz
- Department of Hematology and Oncology, University Children’s Hospital, Medical Faculty Mannheim, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim, Germany
| | - Ulrich S. Schwarz
- Institute for Theoretical Physics, Heidelberg University, Philosophenweg 16, 69120 Heidelberg, Germany
- BioQuant-Center for Quantitative Biology, Heidelberg University, Im Neuenheimer Feld 267, 69120 Heidelberg, Germany
| | - Mike Heilemann
- Institute for Physical and Theoretical Chemistry, Goethe-University Frankfurt, Max-von-Laue-Str. 7, 60438 Frankfurt, Germany
- BioQuant-Center for Quantitative Biology, Heidelberg University, Im Neuenheimer Feld 267, 69120 Heidelberg, Germany
| | - Michael Lanzer
- Center of Infectious Diseases, Parasitology, Universitätsklinikum Heidelberg, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
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12
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Kaur J, Kumar V, Singh AP, Singh V, Bisht A, Dube T, Panda JJ, Behl A, Mishra PC, Hora R. Plasmodium falciparumprotein ‘PfJ23’ hosts distinct binding sites for major virulence factor ‘PfEMP1’ and Maurer's cleft marker ‘PfSBP1’. Pathog Dis 2018; 76:5255127. [DOI: 10.1093/femspd/fty090] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Accepted: 12/19/2018] [Indexed: 01/09/2023] Open
Affiliation(s)
- Jasweer Kaur
- Department of Molecular Biology and Biochemistry, Guru Nanak Dev University, Amritsar, Punjab, India
| | - Vikash Kumar
- Department of Molecular Biology and Biochemistry, Guru Nanak Dev University, Amritsar, Punjab, India
| | - Amrit Pal Singh
- Department of Pharmaceutical sciences, Guru Nanak Dev University, Amritsar, Punjab, India
| | - Vineeta Singh
- National Institute of Malaria Research, Sector 8 Dwarka, New Delhi, 110077 India. 4. Institute of Nanoscience and Technology, Habitat Centre, Phase 10, Sector 64, Sahibzada Ajit Singh Nagar, Punjab 160062 India
| | - Anjali Bisht
- Institute of Nanoscience and Technology, Mohali, Punjab, India
| | - Taru Dube
- Institute of Nanoscience and Technology, Mohali, Punjab, India
| | | | - Ankita Behl
- Department of Biotechnology, Guru Nanak Dev University, Amritsar, Punjab, India
| | | | - Rachna Hora
- Department of Molecular Biology and Biochemistry, Guru Nanak Dev University, Amritsar, Punjab, India
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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.
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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
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Children with cerebral malaria or severe malarial anaemia lack immunity to distinct variant surface antigen subsets. Sci Rep 2018; 8:6281. [PMID: 29674705 PMCID: PMC5908851 DOI: 10.1038/s41598-018-24462-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Accepted: 03/28/2018] [Indexed: 01/08/2023] Open
Abstract
Variant surface antigens (VSAs) play a critical role in severe malaria pathogenesis. Defining gaps, or “lacunae”, in immunity to these Plasmodium falciparum antigens in children with severe malaria would improve our understanding of vulnerability to severe malaria and how protective immunity develops. Using a protein microarray with 179 antigen variants from three VSA families as well as more than 300 variants of three other blood stage P. falciparum antigens, reactivity was measured in sera from Malian children with cerebral malaria or severe malarial anaemia and age-matched controls. Sera from children with severe malaria recognized fewer extracellular PfEMP1 fragments and were less reactive to specific fragments compared to controls. Following recovery from severe malaria, convalescent sera had increased reactivity to certain non-CD36 binding PfEMP1s, but not other malaria antigens. Sera from children with severe malarial anaemia reacted to fewer VSAs than did sera from children with cerebral malaria, and both of these groups had lacunae in their seroreactivity profiles in common with children who had both cerebral malaria and severe malarial anaemia. This microarray-based approach may identify a subset of VSAs that could inform the development of a vaccine to prevent severe disease or a diagnostic test to predict at-risk children.
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15
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Kumar V, Kaur J, Singh AP, Singh V, Bisht A, Panda JJ, Mishra PC, Hora R. PHIST
c protein family members localize to different subcellular organelles and bind
Plasmodium falciparum
major virulence factor
Pf
EMP
‐1. FEBS J 2017; 285:294-312. [DOI: 10.1111/febs.14340] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Revised: 10/15/2017] [Accepted: 11/15/2017] [Indexed: 01/14/2023]
Affiliation(s)
- Vikash Kumar
- Department of Molecular Biology and Biochemistry Guru Nanak Dev University Amritsar India
| | - Jasweer Kaur
- Department of Molecular Biology and Biochemistry Guru Nanak Dev University Amritsar India
| | - Amrit P. Singh
- Department of Pharmaceutical Sciences Guru Nanak Dev University Amritsar India
| | - Vineeta Singh
- National Institute of Malaria Research New Delhi India
| | - Anjali Bisht
- Institute of Nano Science and Technology Mohali India
| | | | - Prakash C. Mishra
- Department of Biotechnology Guru Nanak Dev University Amritsar India
| | - Rachna Hora
- Department of Molecular Biology and Biochemistry Guru Nanak Dev University Amritsar India
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16
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Structural analysis of P. falciparum KAHRP and PfEMP1 complexes with host erythrocyte spectrin suggests a model for cytoadherent knob protrusions. PLoS Pathog 2017; 13:e1006552. [PMID: 28806784 PMCID: PMC5570508 DOI: 10.1371/journal.ppat.1006552] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 08/24/2017] [Accepted: 07/25/2017] [Indexed: 11/19/2022] Open
Abstract
Plasmodium falciparum Erythrocyte Membrane Protein 1 (PfEMP1) and Knob-associated Histidine-rich Protein (KAHRP) are directly linked to malaria pathology. PfEMP1 and KAHRP cluster on protrusions (knobs) on the P. falciparum-infected erythrocyte surface and enable pathogenic cytoadherence of infected erythrocytes to the host microvasculature, leading to restricted blood flow, oxygen deprivation and damage of tissues. Here we characterize the interactions of PfEMP1 and KAHRP with host erythrocyte spectrin using biophysical, structural and computational approaches. These interactions assist knob formation and, thus, promote cytoadherence. We show that the folded core of the PfEMP1 cytosolic domain interacts broadly with erythrocyte spectrin but shows weak, residue-specific preference for domain 17 of α spectrin, which is proximal to the erythrocyte cytoskeletal junction. In contrast, a protein sequence repeat region in KAHRP preferentially associates with domains 10–14 of β spectrin, proximal to the spectrin–ankyrin complex. Structural models of PfEMP1 and KAHRP with spectrin combined with previous microscopy and protein interaction data suggest a model for knob architecture. Formation of cytoadherent knobs on the surface of P. falciparum infected erythrocytes correlates with malaria pathology. Two parasite proteins central for knob formation and cytoadherence, KAHRP and PfEMP1, have previously been shown to bind the erythrocyte cytoskeleton. Both KAHRP and PfEMP1 include large segments of protein disorder, which have previously hampered their analysis. In this study we use biophysics and structural biology tools to analyze the interactions between these proteins and host spectrin. We devise a novel computational tool to help us towards this goal that may be broadly applicable to characterizing other complexes of widespread, disordered Plasmodial proteins and host components. We derive atomistic models of KAHRP–spectrin and PfEMP1 –spectrin complexes, and integrate these into an emerging model of knob architecture.
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17
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Dara A, Drábek EF, Travassos MA, Moser KA, Delcher AL, Su Q, Hostelley T, Coulibaly D, Daou M, Dembele A, Diarra I, Kone AK, Kouriba B, Laurens MB, Niangaly A, Traore K, Tolo Y, Fraser CM, Thera MA, Djimde AA, Doumbo OK, Plowe CV, Silva JC. New var reconstruction algorithm exposes high var sequence diversity in a single geographic location in Mali. Genome Med 2017; 9:30. [PMID: 28351419 PMCID: PMC5368897 DOI: 10.1186/s13073-017-0422-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Accepted: 03/02/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Encoded by the var gene family, highly variable Plasmodium falciparum erythrocyte membrane protein-1 (PfEMP1) proteins mediate tissue-specific cytoadherence of infected erythrocytes, resulting in immune evasion and severe malaria disease. Sequencing and assembling the 40-60 var gene complement for individual infections has been notoriously difficult, impeding molecular epidemiological studies and the assessment of particular var elements as subunit vaccine candidates. METHODS We developed and validated a novel algorithm, Exon-Targeted Hybrid Assembly (ETHA), to perform targeted assembly of var gene sequences, based on a combination of Pacific Biosciences and Illumina data. RESULTS Using ETHA, we characterized the repertoire of var genes in 12 samples from uncomplicated malaria infections in children from a single Malian village and showed them to be as genetically diverse as vars from isolates from around the globe. The gene var2csa, a member of the var family associated with placental malaria pathogenesis, was present in each genome, as were vars previously associated with severe malaria. CONCLUSION ETHA, a tool to discover novel var sequences from clinical samples, will aid the understanding of malaria pathogenesis and inform the design of malaria vaccines based on PfEMP1. ETHA is available at: https://sourceforge.net/projects/etha/ .
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Affiliation(s)
- Antoine Dara
- Division of Malaria Research, Institute for Global Health, University of Maryland School of Medicine, Baltimore, MD USA
| | - Elliott F. Drábek
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD USA
| | - Mark A. Travassos
- Division of Malaria Research, Institute for Global Health, University of Maryland School of Medicine, Baltimore, MD USA
| | - Kara A. Moser
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD USA
| | - Arthur L. Delcher
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD USA
| | - Qi Su
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD USA
| | - Timothy Hostelley
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD USA
| | - Drissa Coulibaly
- Malaria Research and Training Center, University of Science, Techniques and Technologies, Bamako, Mali
| | - Modibo Daou
- Malaria Research and Training Center, University of Science, Techniques and Technologies, Bamako, Mali
| | - Ahmadou Dembele
- Malaria Research and Training Center, University of Science, Techniques and Technologies, Bamako, Mali
| | - Issa Diarra
- Malaria Research and Training Center, University of Science, Techniques and Technologies, Bamako, Mali
| | - Abdoulaye K. Kone
- Malaria Research and Training Center, University of Science, Techniques and Technologies, Bamako, Mali
| | - Bourema Kouriba
- Malaria Research and Training Center, University of Science, Techniques and Technologies, Bamako, Mali
| | - Matthew B. Laurens
- Division of Malaria Research, Institute for Global Health, University of Maryland School of Medicine, Baltimore, MD USA
| | - Amadou Niangaly
- Malaria Research and Training Center, University of Science, Techniques and Technologies, Bamako, Mali
| | - Karim Traore
- Malaria Research and Training Center, University of Science, Techniques and Technologies, Bamako, Mali
| | - Youssouf Tolo
- Malaria Research and Training Center, University of Science, Techniques and Technologies, Bamako, Mali
| | - Claire M. Fraser
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD USA
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD USA
- Department of Medicine, University of Maryland School of Medicine, Baltimore, MD USA
| | - Mahamadou A. Thera
- Malaria Research and Training Center, University of Science, Techniques and Technologies, Bamako, Mali
| | - Abdoulaye A. Djimde
- Malaria Research and Training Center, University of Science, Techniques and Technologies, Bamako, Mali
| | - Ogobara K. Doumbo
- Malaria Research and Training Center, University of Science, Techniques and Technologies, Bamako, Mali
| | - Christopher V. Plowe
- Division of Malaria Research, Institute for Global Health, University of Maryland School of Medicine, Baltimore, MD USA
| | - Joana C. Silva
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD USA
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD USA
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18
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Zhu X, He Y, Liang Y, Kaneko O, Cui L, Cao Y. Tryptophan-rich domains of Plasmodium falciparum SURFIN 4.2 and Plasmodium vivax PvSTP2 interact with membrane skeleton of red blood cell. Malar J 2017; 16:121. [PMID: 28320404 PMCID: PMC5359885 DOI: 10.1186/s12936-017-1772-5] [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: 12/30/2016] [Accepted: 03/10/2017] [Indexed: 11/13/2022] Open
Abstract
Background Plasmodium falciparum dramatically alters the morphology and properties of the infected red blood cells (iRBCs). A large group of exported proteins participate in these parasite-host interactions occurring at the iRBC membrane skeleton. SURFIN4.2 is one of iRBC surface protein that belongs to surface-associated interspersed protein (SURFIN) family. Although the intracellular tryptophan-rich domain (WRD) was proposed to be important for the translocation of SURFINs from Maurer’s clefts to iRBC surface, the molecular basis of this observation has yet to be defined. The WRDs of P. falciparum SURFIN proteins and their orthologous Plasmodium vivax subtelomeric transmembrane proteins (PvSTPs) show homology to the intracellular regions of PfEMP1 and Pf332, both of which are involved in RBC membrane skeleton interactions, and contribute to malaria pathology. Methods Two transfected lines expressing recombinant SURFINs (NTC-GFP and NTC-4.2WRD2-GFP) of the 3D7 sequence were generated by transfection in P. falciparum. In vitro binding assays were performed by using recombinant WRDs of SURFIN4.2/PvSTP2 and inside-out vesicles (IOVs). The interactions between the recombinant WRDs of SURFIN4.2/PvSTP2 with actin and spectrin were evaluated by the actin spin down assay and an enzyme-linked immunosorbent assay based binding assays, respectively. Results The recombinant SURFINs (NTC-4.2WRD2-GFP), in which the second WRD from SURFIN4.2 was added back to NTC-GFP, show diffused pattern of fluorescence in the iRBC cytosol. Furthermore, WRDs of SURFIN4.2/PvSTP2 were found to directly interact with the IOVs of RBC, with binding affinities ranging from 0.26 to 0.68 μM, values that are comparable to other reported parasite proteins that bind to the RBC membrane skeleton. Further experiments revealed that the second WRD of SURFIN4.2 bound to F-actin (Kd = 5.16 μM) and spectrin (Kd = 0.51 μM). Conclusions Because PfEMP1 and Pf332 also bind to actin and/or spectrin, the authors propose that the interaction between WRD and RBC membrane skeleton might be a common feature of WRD-containing proteins and may be important for the translocation of these proteins from Maurer’s clefts to the iRBC surface. The findings suggest a conserved mechanism of host-parasite interactions and targeting this interaction may disrupt the iRBC surface exposure of Plasmodium virulence-related proteins. Electronic supplementary material The online version of this article (doi:10.1186/s12936-017-1772-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Xiaotong Zhu
- Department of Immunology, College of Basic Medical Science, China Medical University, Shenyang, 110122, Liaoning, China
| | - Yang He
- Department of Immunology, College of Basic Medical Science, China Medical University, Shenyang, 110122, Liaoning, China
| | - Yifan Liang
- 98K 73B Seven-year Programme 127306, China Medical University, Shenyang, 110001, Liaoning, China
| | - Osamu Kaneko
- Department of Protozoology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, 1-12-4 Sakamoto, Nagasaki, 852-8523, Japan
| | - Liwang Cui
- Department of Immunology, College of Basic Medical Science, China Medical University, Shenyang, 110122, Liaoning, China. .,Department of Entomology, The Pennsylvania State University, University Park, PA, 16802, USA.
| | - Yaming Cao
- Department of Immunology, College of Basic Medical Science, China Medical University, Shenyang, 110122, Liaoning, China.
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19
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Oxidative insult can induce malaria-protective trait of sickle and fetal erythrocytes. Nat Commun 2016; 7:13401. [PMID: 27824335 PMCID: PMC5105170 DOI: 10.1038/ncomms13401] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Accepted: 09/29/2016] [Indexed: 01/06/2023] Open
Abstract
Plasmodium falciparum infections can cause severe malaria, but not every infected person develops life-threatening complications. In particular, carriers of the structural haemoglobinopathies S and C and infants are protected from severe disease. Protection is associated with impaired parasite-induced host actin reorganization, required for vesicular trafficking of parasite-encoded adhesins, and reduced cytoadherence of parasitized erythrocytes in the microvasculature. Here we show that aberrant host actin remodelling and the ensuing reduced cytoadherence result from a redox imbalance inherent to haemoglobinopathic and fetal erythrocytes. We further show that a transient oxidative insult to wild-type erythrocytes before infection with P. falciparum induces the phenotypic features associated with the protective trait of haemoglobinopathic and fetal erythrocytes. Moreover, pretreatment of mice with the pro-oxidative nutritional supplement menadione mitigate the development of experimental cerebral malaria. Our results identify redox imbalance as a causative principle of protection from severe malaria, which might inspire host-directed intervention strategies.
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20
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Exported Epoxide Hydrolases Modulate Erythrocyte Vasoactive Lipids during Plasmodium falciparum Infection. mBio 2016; 7:mBio.01538-16. [PMID: 27795395 PMCID: PMC5082902 DOI: 10.1128/mbio.01538-16] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Erythrocytes are reservoirs of important epoxide-containing lipid signaling molecules, including epoxyeicosatrienoic acids (EETs). EETs function as vasodilators and anti-inflammatory modulators in the bloodstream. Bioactive EETs are hydrolyzed to less active diols (dihydroxyeicosatrienoic acids) by epoxide hydrolases (EHs). The malaria parasite Plasmodium falciparum infects host red blood cells (RBCs) and exports hundreds of proteins into the RBC compartment. In this study, we show that two parasite epoxide hydrolases, P. falciparum epoxide hydrolases 1 (PfEH1) and 2 (PfEH2), both with noncanonical serine nucleophiles, are exported to the periphery of infected RBCs. PfEH1 and PfEH2 were successfully expressed in Escherichia coli, and they hydrolyzed physiologically relevant erythrocyte EETs. Mutations in active site residues of PfEH1 ablated the ability of the enzyme to hydrolyze an epoxide substrate. Overexpression of PfEH1 or PfEH2 in parasite-infected RBCs resulted in a significant alteration in the epoxide fatty acids stored in RBC phospholipids. We hypothesize that the parasite disruption of epoxide-containing signaling lipids leads to perturbed vascular function, creating favorable conditions for binding and sequestration of infected RBCs to the microvascular endothelium. The malaria parasite exports hundreds of proteins into the erythrocyte compartment. However, for most of these proteins, their physiological function is unknown. In this study, we investigate two “hypothetical” proteins of the α/β-hydrolase fold family that share sequence similarity with epoxide hydrolases (EHs)—enzymes that destroy bioactive epoxides. Altering EH expression in parasite-infected erythrocytes resulted in a significant change in the epoxide fatty acids stored in the host cell. We propose that these EH enzymes may help the parasite to manipulate host blood vessel opening and inflame the vessel walls as they pass through the circulation system. Understanding how the malaria parasite interacts with its host RBCs will aid in our ability to combat this deadly disease.
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21
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de Koning-Ward TF, Dixon MW, Tilley L, Gilson PR. Plasmodium species: master renovators of their host cells. Nat Rev Microbiol 2016; 14:494-507. [DOI: 10.1038/nrmicro.2016.79] [Citation(s) in RCA: 117] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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22
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Bertin GI, Sabbagh A, Argy N, Salnot V, Ezinmegnon S, Agbota G, Ladipo Y, Alao JM, Sagbo G, Guillonneau F, Deloron P. Proteomic analysis of Plasmodium falciparum parasites from patients with cerebral and uncomplicated malaria. Sci Rep 2016; 6:26773. [PMID: 27245217 PMCID: PMC4887788 DOI: 10.1038/srep26773] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Accepted: 05/05/2016] [Indexed: 01/31/2023] Open
Abstract
Plasmodium falciparum is responsible of severe malaria, including cerebral malaria (CM). During its intra-erythrocytic maturation, parasite-derived proteins are expressed, exported and presented at the infected erythrocyte membrane. To identify new CM-specific parasite membrane proteins, we conducted a mass spectrometry-based proteomic study and compared the protein expression profiles between 9 CM and 10 uncomplicated malaria (UM) samples. Among the 1097 Plasmodium proteins identified, we focused on the 499 membrane-associated and hypothetical proteins for comparative analysis. Filter-based feature selection methods combined with supervised data analysis identified a subset of 29 proteins distinguishing CM and UM samples with high classification accuracy. A hierarchical clustering analysis of these 29 proteins based on the similarity of their expression profiles revealed two clusters of 15 and 14 proteins, respectively under- and over-expressed in CM. Among the over-expressed proteins, the MESA protein is expressed at the erythrocyte membrane, involved in proteins trafficking and in the export of variant surface antigens (VSAs), but without antigenic function. Antigen 332 protein is exported at the erythrocyte, also involved in protein trafficking and in VSAs export, and exposed to the immune system. Our proteomics data demonstrate an association of selected proteins in the pathophysiology of CM.
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Affiliation(s)
- Gwladys I Bertin
- Institut de Recherche pour le Développement (IRD), UMR216 - MERIT, Paris, France.,COMUE Sorbonne Paris Cité, Faculté de Pharmacie de Paris, Paris Descartes University, Paris 75006, France
| | - Audrey Sabbagh
- Institut de Recherche pour le Développement (IRD), UMR216 - MERIT, Paris, France.,COMUE Sorbonne Paris Cité, Faculté de Pharmacie de Paris, Paris Descartes University, Paris 75006, France
| | - Nicolas Argy
- Institut de Recherche pour le Développement (IRD), UMR216 - MERIT, Paris, France.,COMUE Sorbonne Paris Cité, Faculté de Pharmacie de Paris, Paris Descartes University, Paris 75006, France.,Parasitology laboratory, Bichat-Claude Bernard hospital, Paris 75018, France.,French national reference center of malaria laboratory, Bichat-Claude Bernard hospital, Paris 75018, France
| | - Virginie Salnot
- COMUE Sorbonne Paris Cité, Faculté de Pharmacie de Paris, Paris Descartes University, Paris 75006, France.,3P5 Proteomics facility, Université Paris Descartes, Paris, France
| | - Sem Ezinmegnon
- Centre d'Étude et de Recherche sur le Paludisme Associé à la Grossesse et l'Enfance (CERPAGE), Cotonou, Benin
| | - Gino Agbota
- Institut de Recherche pour le Développement (IRD), UMR216 - MERIT, Paris, France.,COMUE Sorbonne Paris Cité, Faculté de Pharmacie de Paris, Paris Descartes University, Paris 75006, France.,Centre d'Étude et de Recherche sur le Paludisme Associé à la Grossesse et l'Enfance (CERPAGE), Cotonou, Benin
| | - Yélé Ladipo
- Paediatric Department, Mother and child hospital (HOMEL), Cotonou, Benin
| | - Jules M Alao
- Paediatric Department, Mother and child hospital (HOMEL), Cotonou, Benin
| | - Gratien Sagbo
- Paediatric Department, Centre National Hospitalo-Universitaire (CNHU), Cotonou, Benin
| | - François Guillonneau
- COMUE Sorbonne Paris Cité, Faculté de Pharmacie de Paris, Paris Descartes University, Paris 75006, France.,3P5 Proteomics facility, Université Paris Descartes, Paris, France
| | - Philippe Deloron
- Institut de Recherche pour le Développement (IRD), UMR216 - MERIT, Paris, France.,COMUE Sorbonne Paris Cité, Faculté de Pharmacie de Paris, Paris Descartes University, Paris 75006, France
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23
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Oberli A, Zurbrügg L, Rusch S, Brand F, Butler ME, Day JL, Cutts EE, Lavstsen T, Vakonakis I, Beck HP. Plasmodium falciparum Plasmodium helical interspersed subtelomeric proteins contribute to cytoadherence and anchor P. falciparum erythrocyte membrane protein 1 to the host cell cytoskeleton. Cell Microbiol 2016; 18:1415-28. [PMID: 26916885 PMCID: PMC5103180 DOI: 10.1111/cmi.12583] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Revised: 02/15/2016] [Accepted: 02/21/2016] [Indexed: 01/12/2023]
Abstract
Adherence of Plasmodium falciparum‐infected erythrocytes to host endothelium is conferred through the parasite‐derived virulence factor P. falciparum erythrocyte membrane protein 1 (PfEMP1), the major contributor to malaria severity. PfEMP1 located at knob structures on the erythrocyte surface is anchored to the cytoskeleton, and the Plasmodium helical interspersed subtelomeric (PHIST) gene family plays a role in many host cell modifications including binding the intracellular domain of PfEMP1. Here, we show that conditional reduction of the PHIST protein PFE1605w strongly reduces adhesion of infected erythrocytes to the endothelial receptor CD36. Adhesion to other endothelial receptors was less affected or even unaltered by PFE1605w depletion, suggesting that PHIST proteins might be optimized for subsets of PfEMP1 variants. PFE1605w does not play a role in PfEMP1 transport, but it directly interacts with both the intracellular segment of PfEMP1 and with cytoskeletal components. This is the first report of a PHIST protein interacting with key molecules of the cytoadherence complex and the host cytoskeleton, and this functional role seems to play an essential role in the pathology of P. falciparum.
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Affiliation(s)
- Alexander Oberli
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Laura Zurbrügg
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Sebastian Rusch
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Françoise Brand
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | | | - Jemma L Day
- Department of Biochemistry, University of Oxford, Oxford, UK
| | - Erin E Cutts
- Department of Biochemistry, University of Oxford, Oxford, UK
| | - Thomas Lavstsen
- Centre for Medical Parasitology, Department of International Health, Immunology, and Microbiology, University of Copenhagen, Copenhagen, Denmark.,Department of Infectious Diseases, Rigshospitalet, Copenhagen, Denmark
| | | | - Hans-Peter Beck
- Swiss Tropical and Public Health Institute, Basel, Switzerland. .,University of Basel, Basel, Switzerland.
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24
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Helms G, Dasanna AK, Schwarz US, Lanzer M. Modeling cytoadhesion of Plasmodium falciparum-infected erythrocytes and leukocytes-common principles and distinctive features. FEBS Lett 2016; 590:1955-71. [PMID: 26992823 PMCID: PMC5071704 DOI: 10.1002/1873-3468.12142] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2015] [Revised: 02/01/2016] [Accepted: 02/07/2016] [Indexed: 12/25/2022]
Abstract
Cytoadhesion of Plasmodium falciparum‐infected erythrocytes to the microvascular endothelial lining shares striking similarities to cytoadhesion of leukocytes. In both cases, adhesins are presented in structures that raise them above the cell surface. Another similarity is the enhancement of adhesion under physical force (catch bonding). Here, we review recent advances in our understanding of the molecular and biophysical mechanisms underlying cytoadherence in both cellular systems. We describe how imaging, flow chamber experiments, single‐molecule measurements, and computational modeling have been used to decipher the relevant processes. We conclude that although the parasite seems to induce processes that resemble the cytoadherence of leukocytes, the mechanics of erythrocytes is such that the resulting behavior in shear flow is fundamentally different.
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Affiliation(s)
- Gesa Helms
- Department of Infectious Diseases, Heidelberg University, Germany
| | - Anil Kumar Dasanna
- BioQuant, Heidelberg, Germany.,Institute for Theoretical Physics, Heidelberg University, Germany
| | - Ulrich S Schwarz
- BioQuant, Heidelberg, Germany.,Institute for Theoretical Physics, Heidelberg University, Germany
| | - Michael Lanzer
- Department of Infectious Diseases, Heidelberg University, Germany
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25
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Abstract
Invasive stages of apicomplexan parasites require a host cell to survive, proliferate and advance to the next life cycle stage. Once invasion is achieved, apicomplexans interact closely with the host cell cytoskeleton, but in many cases the different species have evolved distinct mechanisms and pathways to modulate the structural organization of cytoskeletal filaments. The host cell cytoskeleton is a complex network, largely, but not exclusively, composed of microtubules, actin microfilaments and intermediate filaments, all of which are modulated by associated proteins, and it is involved in diverse functions including maintenance of cell morphology and mechanical support, migration, signal transduction, nutrient uptake, membrane and organelle trafficking and cell division. The ability of apicomplexans to modulate the cytoskeleton to their own advantage is clearly beneficial. We here review different aspects of the interactions of apicomplexans with the three main cytoskeletal filament types, provide information on the currently known parasite effector proteins and respective host cell targets involved, and how these interactions modulate the host cell physiology. Some of these findings could provide novel targets that could be exploited for the development of preventive and/or therapeutic strategies.
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26
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Three-dimensional analysis of morphological changes in the malaria parasite infected red blood cell by serial block-face scanning electron microscopy. J Struct Biol 2016; 193:162-171. [PMID: 26772147 DOI: 10.1016/j.jsb.2016.01.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Revised: 12/16/2015] [Accepted: 01/05/2016] [Indexed: 01/22/2023]
Abstract
The human malaria parasite, Plasmodium falciparum, exhibits morphological changes during the blood stage cycle in vertebrate hosts. Here, we used serial block-face scanning electron microscopy (SBF-SEM) to visualize the entire structures of P. falciparum-infected red blood cells (iRBCs) and to examine their morphological and volumetric changes at different stages. During developmental stages, the parasite forms Maurer's clefts and vesicles in the iRBC cytoplasm and knobs on the iRBC surface, and extensively remodels the iRBC structure for proliferation of the parasite. In our observations, the Maurer's clefts and vesicles in the P. falciparum-iRBCs, resembling the so-called tubovesicular network (TVN), were not connected to each other, and continuous membrane networks were not observed between the parasitophorous vacuole membrane (PVM) and the iRBC cytoplasmic membrane. In the volumetric analysis, the iRBC volume initially increased and then decreased to the end of the blood stage cycle. This suggests that it is necessary to absorb a substantial amount of nutrients from outside the iRBC during the initial stage, but to release waste materials from inside the iRBC at the multinucleate stage. Transportation of the materials may be through the iRBC membrane, rather than a special structure formed by the parasite, because there is no direct connection between the iRBC membrane and the parasite. These results provide new insights as to how the malaria parasite grows in the iRBC and remodels iRBC structure during developmental stages; these observation can serve as a baseline for further experiments on the effects of therapeutic agents on malaria.
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27
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Malaria Parasite Proteins and Their Role in Alteration of the Structure and Function of Red Blood Cells. ADVANCES IN PARASITOLOGY 2015; 91:1-86. [PMID: 27015947 DOI: 10.1016/bs.apar.2015.09.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Malaria, caused by Plasmodium spp., continues to be a major threat to human health and a significant cause of socioeconomic hardship in many countries. Almost half of the world's population live in malaria-endemic regions and many of them suffer one or more, often life-threatening episodes of malaria every year, the symptoms of which are attributable to replication of the parasite within red blood cells (RBCs). In the case of Plasmodium falciparum, the species responsible for most malaria-related deaths, parasite replication within RBCs is accompanied by striking alterations to the morphological, biochemical and biophysical properties of the host cell that are essential for the parasites' survival. To achieve this, the parasite establishes a unique and extensive protein export network in the infected RBC, dedicating at least 6% of its genome to the process. Understanding the full gamut of proteins involved in this process and the mechanisms by which P. falciparum alters the structure and function of RBCs is important both for a more complete understanding of the pathogenesis of malaria and for development of new therapeutic strategies to prevent or treat this devastating disease. This review focuses on what is currently known about exported parasite proteins, their interactions with the RBC and their likely pathophysiological consequences.
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28
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A spiral scaffold underlies cytoadherent knobs in Plasmodium falciparum-infected erythrocytes. Blood 2015; 127:343-51. [PMID: 26637786 DOI: 10.1182/blood-2015-10-674002] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Accepted: 11/30/2015] [Indexed: 12/11/2022] Open
Abstract
Much of the virulence of Plasmodium falciparum malaria is caused by cytoadherence of infected erythrocytes, which promotes parasite survival by preventing clearance in the spleen. Adherence is mediated by membrane protrusions known as knobs, whose formation depends on the parasite-derived, knob-associated histidine-rich protein (KAHRP). Knobs are required for cytoadherence under flow conditions, and they contain both KAHRP and the parasite-derived erythrocyte membrane protein PfEMP1. Using electron tomography, we have examined the 3-dimensional structure of knobs in detergent-insoluble skeletons of P falciparum 3D7 schizonts. We describe a highly organized knob skeleton composed of a spiral structure coated by an electron-dense layer underlying the knob membrane. This knob skeleton is connected by multiple links to the erythrocyte cytoskeleton. We used immuno-electron microscopy (EM) to locate KAHRP in these structures. The arrangement of membrane proteins in the knobs, visualized by high-resolution freeze-fracture scanning EM, is distinct from that in the surrounding erythrocyte membrane, with a structure at the apex that likely represents the adhesion site. Thus, erythrocyte knobs in P falciparum infection contain a highly organized skeleton structure underlying a specialized region of membrane. We propose that the spiral and dense coat organize the cytoadherence structures in the knob, and anchor them into the erythrocyte cytoskeleton. The high density of knobs and their extensive mechanical linkage suggest an explanation for the rigidification of the cytoskeleton in infected cells, and for the transmission to the cytoskeleton of shear forces experienced by adhering cells.
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29
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Abstract
Plasmodium falciparum is the protozoan parasite that causes most malaria-associated morbidity and mortality in humans with over 500,000 deaths annually. The disease symptoms are associated with repeated cycles of invasion and asexual multiplication inside red blood cells of the parasite. Partial, non-sterile immunity to P. falciparum malaria develops only after repeated infections and continuous exposure. The successful evasion of the human immune system relies on the large repertoire of antigenically diverse parasite proteins displayed on the red blood cell surface and on the merozoite membrane where they are exposed to the human immune system. Expression switching of these polymorphic proteins between asexual parasite generations provides an efficient mechanism to adapt to the changing environment in the host and to maintain chronic infection. This chapter discusses antigenic diversity and variation in the malaria parasite and our current understanding of the molecular mechanisms that direct the expression of these proteins.
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Affiliation(s)
- Michaela Petter
- Department of Medicine Royal Melbourne Hospital, Peter Doherty Institute, University of Melbourne, 792 Elizabeth Street, Melbourne, VIC, 3010, Australia.
| | - Michael F Duffy
- Department of Medicine Royal Melbourne Hospital, Peter Doherty Institute, University of Melbourne, 792 Elizabeth Street, Melbourne, VIC, 3010, Australia.
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30
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Kagaya W, Miyazaki S, Yahata K, Ohta N, Kaneko O. The Cytoplasmic Region of Plasmodium falciparum SURFIN4.2 Is Required for Transport from Maurer's Clefts to the Red Blood Cell Surface. Trop Med Health 2015; 43:265-72. [PMID: 26865830 PMCID: PMC4689606 DOI: 10.2149/tmh.2015-38] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2015] [Accepted: 10/28/2015] [Indexed: 12/22/2022] Open
Abstract
Background: Plasmodium, the causative agent of malaria, exports many proteins to the surface of the infected red blood cell (iRBC) in order to modify it toward a structure more suitable for parasite development and survival. One such exported protein, SURFIN4.2, from the parasite of human malignant malaria, P. falciparum, was identified in the trypsin-cleaved protein fraction from the iRBC surface, and is thereby inferred to be exposed on the iRBC surface. SURFIN4.2 also localize to Maurer’s clefts—parasite-derived membranous structures established in the RBC cytoplasm and tethered to the RBC membrane—and their role in trafficking suggests that they are a pathway for SURFIN4.2 transport to the iRBC surface. It has not been determined the participation of protein domains and motifs within SURFIN4.2 in transport from Maurer’s clefts to the iRBC surface; and herein we examined if the SURFIN4.2 intracellular region containing tryptophan-rich (WR) domain is required for its exposure on the iRBC surface. Results: We generated two transgenic parasite lines which express modified SURFIN4.2, with or without a part of the intracellular region. Both recombinant SURFIN4.2 proteins were exported to Maurer’s clefts. However, only SURFIN4.2 possessing the intracellular region was efficiently cleaved by surface treatment of iRBC with proteinase K. Conclusions: These results indicate that SURFIN4.2 is exposed on the iRBC surface and that the intracellular region containing WR domain plays a role on the transport from Maurer’s clefts to the iRBC membrane.
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Affiliation(s)
- Wataru Kagaya
- Section of Environmental Parasitology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo, Tokyo 113-0034, Japan; Department of Protozoology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Nagasaki, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan
| | - Shinya Miyazaki
- Department of Protozoology, Institute of Tropical Medicine (NEKKEN), Nagasaki University , Nagasaki, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan
| | - Kazuhide Yahata
- Department of Protozoology, Institute of Tropical Medicine (NEKKEN), Nagasaki University , Nagasaki, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan
| | - Nobuo Ohta
- Section of Environmental Parasitology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University , 1-5-45 Yushima, Bunkyo, Tokyo 113-0034, Japan
| | - Osamu Kaneko
- Department of Protozoology, Institute of Tropical Medicine (NEKKEN), Nagasaki University , Nagasaki, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan
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31
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Subudhi AK, Boopathi PA, Pandey I, Kohli R, Karwa R, Middha S, Acharya J, Kochar SK, Kochar DK, Das A. Plasmodium falciparum complicated malaria: Modulation and connectivity between exportome and variant surface antigen gene families. Mol Biochem Parasitol 2015; 201:31-46. [PMID: 26022315 DOI: 10.1016/j.molbiopara.2015.05.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Revised: 05/20/2015] [Accepted: 05/21/2015] [Indexed: 12/27/2022]
Abstract
In temperate and sub-tropical regions of Asia and Latin America, complicated malaria manifested as hepatic dysfunction or renal dysfunction is seen in all age groups. There has been a concerted focus on understanding the patho-physiological and molecular basis of complicated malaria in children, much less is known about it in adults. We report here, the analysis of data from a custom, cross strain microarray (Agilent Platform) using material from adult patient samples, showing hepatic dysfunction or renal failure. These are the most common manifestations seen in adults along with cerebral malaria. The data has been analyzed with reference to variant surface antigens, encoded by the var, rifin and stevor gene families. The differential regulation profiles of key genes (comparison between Plasmodium falciparum complicated and uncomplicated isolates) have been observed. The exportome has been analyzed using similar parameters. Gene ontology term based functional enrichment of differentially regulated genes identified, up-regulated genes statistically enriched (P<0.05) to critical biological processes like generation of precursor metabolite and energy, chromosome organization and electron transport chain. Systems network based functional enrichment of overall differentially regulated genes yielded a similar result. We are reporting here, up-regulation of var group B and C genes whose proteins are predicted to interact with CD36 receptor in the host, the up-regulation of domain cassette 13 (DC13) containing var group A, as also the up-regulation of group A rifins and many of the stevors. This is contrary to most other reports from pediatric patients, with cerebral malaria where the up-regulation of mostly var A group genes have been seen. A protein-protein interaction based network has been created and analysis performed. This co-expression and text mining based network has shown overall connectivity between the variant surface antigens (VSA) and the exportome. The up-regulation of var group B and C genes encoding PfEMP1 with different domain architecture would be important for deciding strategies for disease prevention.
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Affiliation(s)
- Amit Kumar Subudhi
- Department of Biological Sciences, Birla Institute of Technology and Science (BITS), Pilani, Rajasthan, India.
| | - P A Boopathi
- Department of Biological Sciences, Birla Institute of Technology and Science (BITS), Pilani, Rajasthan, India.
| | - Isha Pandey
- Department of Biological Sciences, Birla Institute of Technology and Science (BITS), Pilani, Rajasthan, India.
| | - Ramandeep Kohli
- Department of Biological Sciences, Birla Institute of Technology and Science (BITS), Pilani, Rajasthan, India.
| | - Rohan Karwa
- Department of Biological Sciences, Birla Institute of Technology and Science (BITS), Pilani, Rajasthan, India.
| | - Sheetal Middha
- Department of Medicine, S.P. Medical College, Bikaner, Rajasthan, India.
| | - Jyoti Acharya
- Department of Medicine, S.P. Medical College, Bikaner, Rajasthan, India.
| | - Sanjay K Kochar
- Department of Medicine, S.P. Medical College, Bikaner, Rajasthan, India.
| | - Dhanpat K Kochar
- Rajasthan University of Health Sciences, Jaipur, Rajasthan, India.
| | - Ashis Das
- Department of Biological Sciences, Birla Institute of Technology and Science (BITS), Pilani, Rajasthan, India.
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32
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Multiple stiffening effects of nanoscale knobs on human red blood cells infected with Plasmodium falciparum malaria parasite. Proc Natl Acad Sci U S A 2015; 112:6068-73. [PMID: 25918423 PMCID: PMC4434686 DOI: 10.1073/pnas.1505584112] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Our coarse-grained molecular dynamics (CGMD) simulations show that the deposition of nanoscale knobs, rather than spectrin network remodeling, is the primary cause of the dramatically increased stiffness of the Plasmodium falciparum (Pf)-infected red blood cell (RBC) membranes. Our analyses further reveal that the knobs stiffen the RBC membrane in a unique manner by simultaneously harnessing composite strengthening, strain hardening, and knob density-dependent vertical coupling effects. In addition to providing a fundamental understanding of the stiffening mechanism of Pf-infected RBCs, our simulation results suggest potential targets for antimalarial therapies. During its asexual development within the red blood cell (RBC), Plasmodium falciparum (Pf), the most virulent human malaria parasite, exports proteins that modify the host RBC membrane. The attendant increase in cell stiffness and cytoadherence leads to sequestration of infected RBCs in microvasculature, which enables the parasite to evade the spleen, and leads to organ dysfunction in severe cases of malaria. Despite progress in understanding malaria pathogenesis, the molecular mechanisms responsible for the dramatic loss of deformability of Pf-infected RBCs have remained elusive. By recourse to a coarse-grained (CG) model that captures the molecular structures of Pf-infected RBC membrane, here we show that nanoscale surface protrusions, known as “knobs,” introduce multiple stiffening mechanisms through composite strengthening, strain hardening, and knob density-dependent vertical coupling. On one hand, the knobs act as structural strengtheners for the spectrin network; on the other, the presence of knobs results in strain inhomogeneity in the spectrin network with elevated shear strain in the knob-free regions, which, given its strain-hardening property, effectively stiffens the network. From the trophozoite to the schizont stage that ensues within 24–48 h of parasite invasion into the RBC, the rise in the knob density results in the increased number of vertical constraints between the spectrin network and the lipid bilayer, which further stiffens the membrane. The shear moduli of Pf-infected RBCs predicted by the CG model at different stages of parasite maturation are in agreement with experimental results. In addition to providing a fundamental understanding of the stiffening mechanisms of Pf-infected RBCs, our simulation results suggest potential targets for antimalarial therapies.
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33
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Hviid L, Jensen ATR. PfEMP1 - A Parasite Protein Family of Key Importance in Plasmodium falciparum Malaria Immunity and Pathogenesis. ADVANCES IN PARASITOLOGY 2015; 88:51-84. [PMID: 25911365 DOI: 10.1016/bs.apar.2015.02.004] [Citation(s) in RCA: 107] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Plasmodium falciparum causes the most severe form of malaria and is responsible for essentially all malaria-related deaths. The accumulation in various tissues of erythrocytes infected by mature P. falciparum parasites can lead to circulatory disturbances and inflammation, and is thought to be a central element in the pathogenesis of the disease. It is mediated by the interaction of parasite ligands on the erythrocyte surface and a range of host receptor molecules in many organs and tissues. Among several proteins and protein families implicated in this process, the P. falciparum erythrocyte membrane protein 1 (PfEMP1) family of high-molecular weight and highly variable antigens appears to be the most prominent. In this chapter, we aim to provide a systematic overview of the current knowledge about these proteins, their structure, their function, how they are presented on the erythrocyte surface, and how the var genes encoding them are regulated. The role of PfEMP1 in the pathogenesis of malaria, PfEMP1-specific immune responses, and the prospect of PfEMP1-specific vaccination against malaria are also covered briefly.
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Affiliation(s)
- Lars Hviid
- Centre for Medical Parasitology, University of Copenhagen and Copenhagen University Hospital (Rigshospitalet), Copenhagen, Denmark
| | - Anja T R Jensen
- Centre for Medical Parasitology, University of Copenhagen and Copenhagen University Hospital (Rigshospitalet), Copenhagen, Denmark
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34
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Abstract
In this issue of Blood, Rieger et al show that malaria parasite infiltration in the human placenta requires a specific geometry and affinity of host receptors to facilitate strong adhesion.
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Dynamic association of PfEMP1 and KAHRP in knobs mediates cytoadherence during Plasmodium invasion. Sci Rep 2015; 5:8617. [PMID: 25726759 PMCID: PMC4345318 DOI: 10.1038/srep08617] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2014] [Accepted: 01/26/2015] [Indexed: 11/27/2022] Open
Abstract
Plasmodium falciparum infected erythrocytes display membrane knobs that are essential for their adherence to vascular endothelia and for prevention of clearance by the spleen. The knob associated histidine rich protein (KAHRP) is indispensable to knob formation and has been implicated in the recruitment and tethering of P. falciparum erythrocyte membrane protein–1 (PfEMP1) by binding to its cytoplasmic domain termed VARC. However, the precise mechanism of interaction between KAHRP and VARC is not very well understood. Here we report that both the proteins co-localize to membrane knobs of P. falciparum infected erythrocytes and have identified four positively charged linear sequence motifs of high intrinsic mobility on KAHRP that interact electrostatically with VARC in solution to form a fuzzy complex. The current study provides molecular insight into interaction between KAHRP and VARC in solution that takes place at membrane knobs.
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Spillman NJ, Beck JR, Goldberg DE. Protein export into malaria parasite-infected erythrocytes: mechanisms and functional consequences. Annu Rev Biochem 2015; 84:813-41. [PMID: 25621510 DOI: 10.1146/annurev-biochem-060614-034157] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Phylum Apicomplexa comprises a large group of obligate intracellular parasites of high medical and veterinary importance. These organisms succeed intracellularly by effecting remarkable changes in a broad range of diverse host cells. The transformation of the host erythrocyte is particularly striking in the case of the malaria parasite Plasmodium falciparum. P. falciparum exports hundreds of proteins that mediate a complex cellular renovation marked by changes in the permeability, rigidity, and cytoadherence properties of the host erythrocyte. The past decade has seen enormous progress in understanding the identity and function of these exported effectors, as well as the mechanisms by which they are trafficked into the host cell. Here we review these advances, place them in the context of host manipulation by related apicomplexans, and propose key directions for future research.
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Cytoadhesion of Plasmodium falciparum-infected erythrocytes to chondroitin-4-sulfate is cooperative and shear enhanced. Blood 2014; 125:383-91. [PMID: 25352129 DOI: 10.1182/blood-2014-03-561019] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Infections with the human malaria parasite Plasmodium falciparum during pregnancy can lead to severe complications for both mother and child, resulting from the cytoadhesion of parasitized erythrocytes in the intervillous space of the placenta. Cytoadherence is conferred by the specific interaction of the parasite-encoded adhesin VAR2CSA with chondroitin-4-sulfate (CSA) present on placental proteoglycans. CSA presented elsewhere in the microvasculature does not afford VAR2CSA-mediated cytoadhesion of parasitized erythrocytes. To address the placenta-specific binding tropism, we investigated the effect of the receptor/ligand arrangement on cytoadhesion, using artificial membranes with different CSA spacing intervals. We found that cytoadhesion is strongly dependent on the CSA distance, with half-maximal adhesion occurring at a CSA distance of 9 ± 1 nm at all hydrodynamic conditions. Moreover, binding to CSA was cooperative and shear stress induced. These findings suggest that the CSA density, together with allosteric effects in VAR2CSA, aid in discriminating between different CSA milieus.
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Zeeshan M, Tyagi RK, Tyagi K, Alam MS, Sharma YD. Host-parasite interaction: selective Pv-fam-a family proteins of Plasmodium vivax bind to a restricted number of human erythrocyte receptors. J Infect Dis 2014; 211:1111-20. [PMID: 25312039 DOI: 10.1093/infdis/jiu558] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Plasmodium vivax synthesizes the largest number of 36 tryptophan-rich proteins belonging to the Pv-fam-a family. These parasite proteins need to be characterized for their biological function because tryptophan-rich proteins from other Plasmodium species have been proposed as vaccine candidates. METHODS Recombinant P. vivax tryptophan-rich antigens (PvTRAgs) were used to determine their erythrocyte-binding activity by a cell-based enzyme-linked immunosorbent assay, flow cytometry, and a rosetting assay. RESULTS Only 4 (PvTRAg26.3, PvTRAg34, PvTRAg36, and PvTRAg36.6) of 21 PvTRAgs bind to host erythrocytes. The cross-competition data indicated that PvTRAg36 and PvTRAg34 share their erythrocyte receptors with previously described proteins PvTRAg38 and PvTRAg33.5, respectively. On the other hand, PvTRAg26.3 and PvTRAg36.6 cross-compete with each other and not with any other PvTRAg, indicating that these 2 proteins bind to the same but yet another set of erythrocyte receptor(s). Together, 10 of 36 PvTRAgs possess erythrocyte-binding activity in which each protein recognizes >1 erythrocyte receptor. Further, each erythrocyte receptor is shared by >1 PvTRAg. CONCLUSIONS This redundancy may be useful for the parasite to invade red blood cells and cause disease pathogenesis, and it can be exploited to develop therapeutics against P. vivax malaria.
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Affiliation(s)
- Mohammad Zeeshan
- Department of Biotechnology, All India Institute of Medical Sciences, New Delhi
| | - Rupesh Kumar Tyagi
- Department of Biotechnology, All India Institute of Medical Sciences, New Delhi
| | - Kriti Tyagi
- Department of Biotechnology, All India Institute of Medical Sciences, New Delhi
| | - Mohd Shoeb Alam
- Department of Biotechnology, All India Institute of Medical Sciences, New Delhi
| | - Yagya Dutta Sharma
- Department of Biotechnology, All India Institute of Medical Sciences, New Delhi
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Tarr SJ, Moon RW, Hardege I, Osborne AR. A conserved domain targets exported PHISTb family proteins to the periphery of Plasmodium infected erythrocytes. Mol Biochem Parasitol 2014; 196:29-40. [PMID: 25106850 PMCID: PMC4165601 DOI: 10.1016/j.molbiopara.2014.07.011] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Revised: 07/24/2014] [Accepted: 07/28/2014] [Indexed: 11/19/2022]
Abstract
Multiple P. falciparum PHISTb proteins localise to the erythrocyte periphery. Solubility profiling indicates that these proteins associate with the red cell cytoskeleton. The PRESAN domain and a preceding N-terminal sequence is a novel targeting domain. A protein targeted to the red cell periphery is essential for parasite survival. P. knowlesi and P. vivax homologous domains also confer similar localisation.
During blood-stage infection, malaria parasites export numerous proteins to the host erythrocyte. The Poly-Helical Interspersed Sub-Telomeric (PHIST) proteins are an exported family that share a common ‘PRESAN’ domain, and include numerous members in Plasmodium falciparum, Plasmodium vivax and Plasmodium knowlesi. In P. falciparum, PHIST proteins have been implicated in protein trafficking and intercellular communication. A number of PHIST proteins are essential for parasite survival. Here, we identify nine members of the PHISTb sub-class of PHIST proteins, including one protein known to be essential for parasite survival, that localise to the erythrocyte periphery. These proteins have solubility characteristics consistent with their association with the erythrocyte cytoskeleton. Together, an extended PRESAN domain, comprising the PRESAN domain and preceding sequence, form a novel targeting-domain that is sufficient to localise a protein to the erythrocyte periphery. We validate the role of this domain in RESA, thus identifying a cytoskeleton-binding domain in RESA that functions independently of its known spectrin-binding domain. Our data suggest that some PHISTb proteins may act as cross-linkers of the erythrocyte cytoskeleton. We also show for the first time that peripherally-localised PHISTb proteins are encoded in genomes of P. knowlesi and vivax indicating a conserved role for the extended PRESAN domain of these proteins in targeting to the erythrocyte periphery.
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Affiliation(s)
- Sarah J Tarr
- Institute of Structural and Molecular Biology, Division of Biosciences, Birkbeck and University College London, London, UK
| | - Robert W Moon
- Division of Parasitology, MRC National Institute for Medical Research, London, UK
| | - Iris Hardege
- Institute of Structural and Molecular Biology, Division of Biosciences, Birkbeck and University College London, London, UK
| | - Andrew R Osborne
- Institute of Structural and Molecular Biology, Division of Biosciences, Birkbeck and University College London, London, UK.
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40
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Oberli A, Slater LM, Cutts E, Brand F, Mundwiler-Pachlatko E, Rusch S, Masik MFG, Erat MC, Beck HP, Vakonakis I. A Plasmodium falciparum PHIST protein binds the virulence factor PfEMP1 and comigrates to knobs on the host cell surface. FASEB J 2014; 28:4420-33. [PMID: 24983468 PMCID: PMC4202109 DOI: 10.1096/fj.14-256057] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Uniquely among malaria parasites, Plasmodium falciparum-infected erythrocytes (iRBCs) develop membrane protrusions, known as knobs, where the parasite adhesion receptor P. falciparum erythrocyte membrane protein 1 (PfEMP1) clusters. Knob formation and the associated iRBC adherence to host endothelium are directly linked to the severity of malaria and are functional manifestations of protein export from the parasite to the iRBC. A family of exported proteins featuring Plasmodium helical interspersed subtelomeric (PHIST) domains has attracted attention, with members being implicated in host-parasite protein interactions and differentially regulated in severe disease and among parasite isolates. Here, we show that PHIST member PFE1605w binds the PfEMP1 intracellular segment directly with Kd = 5 ± 0.6 μM, comigrates with PfEMP1 during export, and locates in knobs. PHIST variants that do not locate in knobs (MAL8P1.4) or bind PfEMP1 30 times more weakly (PFI1780w) used as controls did not display the same pattern. We resolved the first crystallographic structure of a PHIST protein and derived a partial model of the PHIST-PfEMP1 interaction from nuclear magnetic resonance. We propose that PFE1605w reinforces the PfEMP1-cytoskeletal connection in knobs and discuss the possible role of PHIST proteins as interaction hubs in the parasite exportome.
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Affiliation(s)
- Alexander Oberli
- Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland; and
| | - Leanne M Slater
- Department of Biochemistry, University of Oxford, Oxford, UK
| | - Erin Cutts
- Department of Biochemistry, University of Oxford, Oxford, UK
| | - Françoise Brand
- Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland; and
| | - Esther Mundwiler-Pachlatko
- Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland; and
| | - Sebastian Rusch
- Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland; and
| | | | - Michèle C Erat
- Department of Biochemistry, University of Oxford, Oxford, UK
| | - Hans-Peter Beck
- Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland; and
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41
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Proellocks NI, Herrmann S, Buckingham DW, Hanssen E, Hodges EK, Elsworth B, Morahan BJ, Coppel RL, Cooke BM. A lysine-rich membrane-associated PHISTb protein involved in alteration of the cytoadhesive properties of Plasmodium falciparum-infected red blood cells. FASEB J 2014; 28:3103-13. [PMID: 24706359 DOI: 10.1096/fj.14-250399] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The genomes of malaria parasites (Plasmodium spp.) contain a family of genes encoding proteins with a Plasmodium helical interspersed subtelomeric (PHIST) domain, most of which are predicted to be exported into the parasite-infected human red blood cell (iRBC). Here, using transgenic parasites and a combination of cellular, biochemical, and biophysical assays, we have characterized and determined the function of a novel member of the PHIST protein family in Plasmodium falciparum, termed lysine-rich membrane-associated PHISTb (LyMP). LyMP was shown to associate directly with the cytoskeleton of iRBCs where it plays a role in their abnormal ability to adhere to a protein expressed on vascular endothelial cells, resulting in sequestration. Deletion of LyMP dramatically reduced adhesion of iRBCs to CD36 by 55%, which was completely restored to wild-type levels on complementation. Intriguingly, in the absence of LyMP, formation of RBC membrane knobs and the level of surface exposure of the parasites' major cytoadhesive ligand, PfEMP1, were identical to those for the parental parasite line, demonstrating for the first time an additional mechanism that enhances cytoadherence of iRBCs beyond those already recognized. Our findings identify LyMP as a previously unknown RBC cytoskeletal-binding protein that is likely to be of major significance in the complex pathophysiology of falciparum malaria.-Proellocks, N. I., Herrmann, S., Buckingham, D. W., Hanssen, E., Hodges, E. K., Elsworth, B., Morahan, B. J., Coppel, R. L., Cooke, B. M. A lysine-rich membrane-associated PHISTb protein involved in alteration of the cytoadhesive properties of Plasmodium falciparum infected red blood cells.
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Affiliation(s)
| | - Susann Herrmann
- Department of Microbiology, Monash University, Victoria, Australia; and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Victoria, Australia
| | | | - Eric Hanssen
- Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Victoria, Australia
| | - Emma K Hodges
- Department of Microbiology, Monash University, Victoria, Australia; and
| | - Brendan Elsworth
- Department of Microbiology, Monash University, Victoria, Australia; and
| | - Belinda J Morahan
- Department of Microbiology, Monash University, Victoria, Australia; and
| | - Ross L Coppel
- Department of Microbiology, Monash University, Victoria, Australia; and
| | - Brian M Cooke
- Department of Microbiology, Monash University, Victoria, Australia; and
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Interaction of Plasmodium falciparum knob-associated histidine-rich protein (KAHRP) with erythrocyte ankyrin R is required for its attachment to the erythrocyte membrane. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2013; 1838:185-92. [PMID: 24090929 DOI: 10.1016/j.bbamem.2013.09.014] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Revised: 09/21/2013] [Accepted: 09/23/2013] [Indexed: 11/20/2022]
Abstract
The malaria parasite Plasmodium falciparum exports a large number of proteins into the erythrocyte cytoplasm during the asexual intraerythrocytic stage of its life cycle. A subset of these proteins interacts with erythrocyte membrane skeletal proteins and grossly alters the structure and function of the membrane. Several of the exported proteins, such as PfEMP1, PfEMP3, RESA and KAHRP, interact with the preponderant erythrocyte skeleton protein, spectrin. Here we have searched for possible interaction of these four malaria proteins with another major erythrocyte skeleton protein, ankyrin R. We have shown that KAHRP, but none of the other three, binds to ankyrin R. We have mapped the binding site for ankyrin R to a 79-residue segment of the KAHRP sequence, and the reciprocal binding site for KAHRP in ankyrin R to a subdomain (D3) of the 89kDa ankyrin R membrane-binding domain. Interaction of intact ankyrin R with KAHRP was inhibited by the free D3 subdomain. When, moreover, red cells loaded with the soluble D3 subdomain were infected with P. falciparum, KAHRP secreted by the intraerythrocytic parasite no longer migrated to the host cell membrane, but remained diffusely distributed throughout the cytosol. Our findings suggest a potentially important role for interaction of KAHRP with red cell membrane skeleton in promoting the adhesion of malaria-infected red cells to endothelial surfaces, a central element in the pathophysiology of malaria.
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Boddey JA, Cowman AF. PlasmodiumNesting: Remaking the Erythrocyte from the Inside Out. Annu Rev Microbiol 2013; 67:243-69. [DOI: 10.1146/annurev-micro-092412-155730] [Citation(s) in RCA: 91] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Justin A. Boddey
- Division of Infection and Immunity, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia; ,
| | - Alan F. Cowman
- Division of Infection and Immunity, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia; ,
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Gitau EN, Kokwaro GO, Karanja H, Newton CRJC, Ward SA. Plasma and cerebrospinal proteomes from children with cerebral malaria differ from those of children with other encephalopathies. J Infect Dis 2013; 208:1494-503. [PMID: 23888081 PMCID: PMC3789566 DOI: 10.1093/infdis/jit334] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Clinical signs and symptoms of cerebral malaria in children are nonspecific and are seen in other common encephalopathies in malaria-endemic areas. This makes accurate diagnosis difficult in resource-poor settings. Novel malaria-specific diagnostic and prognostic methods are needed. We have used 2 proteomic strategies to identify differentially expressed proteins in plasma and cerebrospinal fluid from children with a diagnosis of cerebral malaria, compared with those with a diagnosis of malaria-slide-negative acute bacterial meningitis and other nonspecific encephalopathies. Here we report the presence of differentially expressed proteins in cerebral malaria in both plasma and cerebrospinal fluid that could be used to better understand pathogenesis and help develop more-specific diagnostic methods. In particular, we report the expression of 2 spectrin proteins that have known Plasmodium falciparum–binding partners involved in the stability of the infected red blood cell, suppressing further invasion and possibly enhancing the red blood cell's ability to sequester in microvasculature.
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Affiliation(s)
- Evelyn N Gitau
- Centre for Geographic Medicine-Coast, KEMRI-Wellcome Trust Research Programme, Kilifi
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45
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Remodeling of human red cells infected with Plasmodium falciparum and the impact of PHIST proteins. Blood Cells Mol Dis 2013; 51:195-202. [PMID: 23880461 DOI: 10.1016/j.bcmd.2013.06.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2013] [Revised: 06/08/2013] [Accepted: 06/10/2013] [Indexed: 01/27/2023]
Abstract
In an infected erythrocyte (iRBC), renovation and decoration are crucial for malarial parasite survival, pathogenesis and reproduction. Host cell remodeling is mediated by an array of diverse parasite-encoded export proteins that traffic within iRBC. These remodeling proteins extensively modify the membrane and cytoskeleton of iRBC and help in formation of parasite-induced novel organelles such as 'Maurer's Cleft (MC), tubulovesicular network (TVN) and parasitophorous vacuole membrane (PVM) inside the iRBC. The genome sequence of Plasmodium falciparum shows expansion of export proteins, which suggests a complex requirement of these export proteins for specific pathogenesis and erythrocyte remodeling. Plasmodium helical intersperse sub-telomeric (PHIST) is a family of seventy-two small export proteins and many of its recently discovered functional characteristics suggest an intriguing putative role in modification of an iRBC. This review highlights the recent advances in parasite genomics, proteomics, and cell biology studies unraveling the host cell modification; providing a speculation on the impact of PHIST proteins in modification of the iRBC.
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46
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Frech C, Chen N. Variant surface antigens of malaria parasites: functional and evolutionary insights from comparative gene family classification and analysis. BMC Genomics 2013; 14:427. [PMID: 23805789 PMCID: PMC3747859 DOI: 10.1186/1471-2164-14-427] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Accepted: 06/19/2013] [Indexed: 11/10/2022] Open
Abstract
Background Plasmodium parasites, the causative agents of malaria, express many variant antigens on cell surfaces. Variant surface antigens (VSAs) are typically organized into large subtelomeric gene families that play critical roles in virulence and immune evasion. Many important aspects of VSA function and evolution remain obscure, impeding our understanding of virulence mechanisms and vaccine development. To gain further insights into VSA function and evolution, we comparatively classified and examined known VSA gene families across seven Plasmodium species. Results We identified a set of ultra-conserved orthologs within the largest Plasmodium gene family pir, which should be considered as high-priority targets for experimental functional characterization and vaccine development. Furthermore, we predict a lipid-binding domain in erythrocyte surface-expressed PYST-A proteins, suggesting a role of this second largest rodent parasite gene family in host cholesterol salvage. Additionally, it was found that PfMC-2TM proteins carry a novel and putative functional domain named MC-TYR, which is conserved in other P. falciparum gene families and rodent parasites. Finally, we present new conclusive evidence that the major Plasmodium VSAs PfEMP1, SICAvar, and SURFIN are evolutionarily linked through a modular and structurally conserved intracellular domain. Conclusion Our comparative analysis of Plasmodium VSA gene families revealed important functional and evolutionary insights, which can now serve as starting points for further experimental studies.
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Affiliation(s)
- Christian Frech
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BC, Canada
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Parish LA, Mai DW, Jones ML, Kitson EL, Rayner JC. A member of the Plasmodium falciparum PHIST family binds to the erythrocyte cytoskeleton component band 4.1. Malar J 2013; 12:160. [PMID: 23663475 PMCID: PMC3658886 DOI: 10.1186/1475-2875-12-160] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2013] [Accepted: 04/30/2013] [Indexed: 11/28/2022] Open
Abstract
Background Plasmodium falciparum parasites export more than 400 proteins into the cytosol of their host erythrocytes. These exported proteins catalyse the formation of knobs on the erythrocyte plasma membrane and an overall increase in erythrocyte rigidity, presumably by modulating the endogenous erythrocyte cytoskeleton. In uninfected erythrocytes, Band 4.1 (4.1R) plays a key role in regulating erythrocyte shape by interacting with multiple proteins through the three lobes of its cloverleaf-shaped N-terminal domain. In P. falciparum-infected erythrocytes, the C-lobe of 4.1R interacts with the P. falciparum protein mature parasite-infected erythrocyte surface antigen (MESA), but it is not currently known whether other P. falciparum proteins bind to other lobes of the 4.1R N-terminal domain. Methods In order to identify novel 4.1R interacting proteins, a yeast two-hybrid screen was performed with a fragment of 4.1R containing both the N- and α-lobes. Positive interactions were confirmed and investigated using site-directed mutagenesis, and antibodies were raised against the interacting partner to characterise it’s expression and distribution in P. falciparum infected erythrocytes. Results Yeast two-hybrid screening identified a positive interaction between the 4.1R N- and α-lobes and PF3D7_0402000. PF3D7_0402000 is a member of a large family of exported proteins that share a domain of unknown function, the PHIST domain. Domain mapping and site-directed mutagenesis established that it is the PHIST domain of PF3D7_0402000 that interacts with 4.1R. Native PF3D7_0402000 is localized at the parasitophorous vacuole membrane (PVM), and colocalizes with a subpopulation of 4.1R. Discussion The function of the majority of P. falciparum exported proteins, including most members of the PHIST family, is unknown, and in only a handful of cases has a direct interaction between P. falciparum-exported proteins and components of the erythrocyte cytoskeleton been established. The interaction between 4.1R and PF3D7_0402000, and localization of PF3D7_0402000 with a sub-population of 4.1R at the PVM could indicate a role in modulating PVM structure. Further investigation into the mechanisms for 4.1R recruitment is needed. Conclusion PF3D7_0402000 was identified as a new binding partner for the major erythrocyte cytoskeletal protein, 4.1R. This interaction is consistent with a growing body of literature that suggests the PHIST family members function by interacting directly with erythrocyte proteins.
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Affiliation(s)
- Lindsay A Parish
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL 35294-2170, USA
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48
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Deponte M, Hoppe HC, Lee MC, Maier AG, Richard D, Rug M, Spielmann T, Przyborski JM. Wherever I may roam: Protein and membrane trafficking in P. falciparum-infected red blood cells. Mol Biochem Parasitol 2012; 186:95-116. [DOI: 10.1016/j.molbiopara.2012.09.007] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2012] [Revised: 09/21/2012] [Accepted: 09/24/2012] [Indexed: 11/27/2022]
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49
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Cyrklaff M, Sanchez CP, Frischknecht F, Lanzer M. Host actin remodeling and protection from malaria by hemoglobinopathies. Trends Parasitol 2012; 28:479-85. [PMID: 22980758 DOI: 10.1016/j.pt.2012.08.003] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2012] [Revised: 08/10/2012] [Accepted: 08/13/2012] [Indexed: 12/13/2022]
Abstract
Many intracellular pathogens remodel the actin of their host cells, and the human malaria parasite Plasmodium falciparum is no exception to this rule. The surprising finding is that several hemoglobinopathies that protect carriers from severe malaria may do so by interfering with host actin reorganization. Here we discuss our current understanding of actin remodeling in P. falciparum-infected erythrocytes, how hemoglobinopathies interfere with this process, and how impaired host actin remodeling affects the virulence of P. falciparum.
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Affiliation(s)
- Marek Cyrklaff
- Department of Infectious Diseases, Parasitology, Heidelberg University, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
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50
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An exported heat shock protein 40 associates with pathogenesis-related knobs in Plasmodium falciparum infected erythrocytes. PLoS One 2012; 7:e44605. [PMID: 22970262 PMCID: PMC3436795 DOI: 10.1371/journal.pone.0044605] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2012] [Accepted: 08/03/2012] [Indexed: 11/19/2022] Open
Abstract
Cell surface structures termed knobs are one of the most important pathogenesis related protein complexes deployed by the malaria parasite Plasmodium falciparum at the surface of the infected erythrocyte. Despite their relevance to the disease, their structure, mechanisms of traffic and their process of assembly remain poorly understood. In this study, we have explored the possible role of a parasite-encoded Hsp40 class of chaperone, namely PFB0090c/PF3D7_0201800 (KAHsp40) in protein trafficking in the infected erythrocyte. We found the gene coding for PF3D7_0201800 to be located in a chromosomal cluster together with knob components KAHRP and PfEMP3. Like the knob components, KAHsp40 too showed the presence of PEXEL motif required for transport to the erythrocyte compartment. Indeed, sub-cellular fractionation and immunofluorescence analysis (IFA) showed KAHsp40 to be exported in the erythrocyte cytoplasm in a stage dependent manner localizing as punctuate spots in the erythrocyte periphery, distinctly from Maurer’s cleft, in structures which could be the reminiscent of knobs. Double IFA analysis revealed co-localization of PF3D7_0201800 with the markers of knobs (KAHRP, PfEMP1 and PfEMP3) and components of the PEXEL translocon (Hsp101, PTEX150). KAHsp40 was also found to be in a complex with KAHRP, PfEMP3 and Hsp101 as confirmed by co-immunoprecipitation assay. Our results suggest potential involvement of a parasite encoded Hsp40 in chaperoning knob assembly in the erythrocyte compartment.
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