1
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Braumann F, Klug D, Kehrer J, Song G, Feng J, Springer TA, Frischknecht F. Conformational change of Plasmodium TRAP is essential for sporozoite migration and transmission. EMBO Rep 2023:e57064. [PMID: 37306042 DOI: 10.15252/embr.202357064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2023] [Revised: 05/15/2023] [Accepted: 05/16/2023] [Indexed: 06/13/2023] Open
Abstract
Eukaryotic cell adhesion and migration rely on surface adhesins connecting extracellular ligands to the intracellular actin cytoskeleton. Plasmodium sporozoites are transmitted by mosquitoes and rely on adhesion and gliding motility to colonize the salivary glands and to reach the liver after transmission. During gliding, the essential sporozoite adhesin TRAP engages actin filaments in the cytoplasm of the parasite, while binding ligands on the substrate through its inserted (I) domain. Crystal structures of TRAP from different Plasmodium species reveal the I domain in closed and open conformations. Here, we probe the importance of these two conformational states by generating parasites expressing versions of TRAP with the I domain stabilized in either the open or closed state with disulfide bonds. Strikingly, both mutations impact sporozoite gliding, mosquito salivary gland entry, and transmission. Absence of gliding in sporozoites expressing the open TRAP I domain can be partially rescued by adding a reducing agent. This suggests that dynamic conformational change is required for ligand binding, gliding motility, and organ invasion and hence sporozoite transmission from mosquito to mammal.
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Affiliation(s)
- Friedrich Braumann
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
| | - Dennis Klug
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
- Université de Strasbourg, CNRS UPR9022, INSERM U963, Institut de Biologie Moléculaire et Cellulaire, Strasbourg, France
| | - Jessica Kehrer
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
- German Center for Infection Research, Partner Site Heidelberg, Heidelberg, Germany
| | - Gaojie Song
- Program in Cellular and Molecular Medicine, Children's Hospital Boston, and Departments of Biological Chemistry and Molecular Pharmacology and of Medicine, Harvard Medical School, Boston, MA, USA
- Department of Biology, East China Normal University, Shanghai, China
| | - Juan Feng
- Program in Cellular and Molecular Medicine, Children's Hospital Boston, and Departments of Biological Chemistry and Molecular Pharmacology and of Medicine, Harvard Medical School, Boston, MA, USA
| | - Timothy A Springer
- Program in Cellular and Molecular Medicine, Children's Hospital Boston, and Departments of Biological Chemistry and Molecular Pharmacology and of Medicine, Harvard Medical School, Boston, MA, USA
| | - Friedrich Frischknecht
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
- German Center for Infection Research, Partner Site Heidelberg, Heidelberg, Germany
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2
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Kehrer J, Pietsch E, Heinze J, Spielmann T, Frischknecht F. Clearing of hemozoin crystals in malaria parasites enables whole-cell STED microscopy. J Cell Sci 2023; 136:286288. [PMID: 36511329 DOI: 10.1242/jcs.260399] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Accepted: 12/05/2022] [Indexed: 12/15/2022] Open
Abstract
Malaria is a devastating mosquito-borne parasitic disease that manifests when Plasmodium parasites replicate within red blood cells. During the development within the red blood cell, the parasite digests hemoglobin and crystalizes the otherwise toxic heme. The resulting hemozoin crystals limit imaging by STED nanoscopy owing to their high light-absorbing capacity, which leads to immediate cell destruction upon contact with the laser. Here, we establish CUBIC-P-based clearing of hemozoin crystals, enabling whole-cell STED nanoscopy of parasites within red blood cells. Hemozoin-cleared infected red blood cells could reliably be stained with antibodies, and hence proteins in the hemozoin-containing digestive vacuole membrane, as well as in secretory vesicles of gametocytes, could be imaged at high resolution. Thus, this process is a valuable tool to study and understand parasite biology and the potential molecular mechanisms mediating drug resistance. This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Jessica Kehrer
- Integrative Parasitology, Center for Integrative Infectious Diseases, Heidelberg University Medical School, Im Neuenheimer Feld 344, 69120 Heidelberg, Germany.,German Center for Infection Research, DZIF, partner site Heidelberg, 69120 Heidelberg, Germany.,Infectious Diseases Imaging Platform, Center for Integrative Infectious Diseases, Heidelberg University Medical School, Im Neuenheimer Feld 344, 69120 Heidelberg, Germany
| | - Emma Pietsch
- Integrative Parasitology, Center for Integrative Infectious Diseases, Heidelberg University Medical School, Im Neuenheimer Feld 344, 69120 Heidelberg, Germany
| | - Julia Heinze
- Integrative Parasitology, Center for Integrative Infectious Diseases, Heidelberg University Medical School, Im Neuenheimer Feld 344, 69120 Heidelberg, Germany
| | - Tobias Spielmann
- Bernhard Nocht Institute for Tropical Medicine, Bernhard Nocht Str. 74, 20359 Hamburg, Germany
| | - Friedrich Frischknecht
- Integrative Parasitology, Center for Integrative Infectious Diseases, Heidelberg University Medical School, Im Neuenheimer Feld 344, 69120 Heidelberg, Germany.,German Center for Infection Research, DZIF, partner site Heidelberg, 69120 Heidelberg, Germany
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3
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Haag M, Kehrer J, Sanchez CP, Deponte M, Lanzer M. Physiological jump in erythrocyte redox potential during Plasmodium falciparum development occurs independent of the sickle cell trait. Redox Biol 2022; 58:102536. [DOI: 10.1016/j.redox.2022.102536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 10/26/2022] [Accepted: 11/08/2022] [Indexed: 11/11/2022] Open
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4
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Kehrer J, Formaglio P, Muthinja JM, Weber S, Baltissen D, Lance C, Ripp J, Grech J, Meissner M, Funaya C, Amino R, Frischknecht F. Plasmodium
sporozoite disintegration during skin passage limits malaria parasite transmission. EMBO Rep 2022; 23:e54719. [PMID: 35403820 PMCID: PMC9253755 DOI: 10.15252/embr.202254719] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 03/17/2022] [Accepted: 03/18/2022] [Indexed: 11/25/2022] Open
Abstract
During transmission of malaria‐causing parasites from mosquitoes to mammals, Plasmodium sporozoites migrate rapidly in the skin to search for a blood vessel. The high migratory speed and narrow passages taken by the parasites suggest considerable strain on the sporozoites to maintain their shape. Here, we show that the membrane‐associated protein, concavin, is important for the maintenance of the Plasmodium sporozoite shape inside salivary glands of mosquitoes and during migration in the skin. Concavin‐GFP localizes at the cytoplasmic periphery and concavin(−) sporozoites progressively round up upon entry of salivary glands. Rounded concavin(−) sporozoites fail to pass through the narrow salivary ducts and are rarely ejected by mosquitoes, while normally shaped concavin(−) sporozoites are transmitted. Strikingly, motile concavin(−) sporozoites disintegrate while migrating through the skin leading to parasite arrest or death and decreased transmission efficiency. Collectively, we suggest that concavin contributes to cell shape maintenance by riveting the plasma membrane to the subtending inner membrane complex. Interfering with cell shape maintenance pathways might hence provide a new strategy to prevent a malaria infection.
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Affiliation(s)
- Jessica Kehrer
- Integrative Parasitology Center for Infectious Diseases Heidelberg University Medical School Heidelberg Germany
- Infectious Diseases Imaging Platform Center for Infectious Diseases Heidelberg University Medical School Heidelberg Germany
| | - Pauline Formaglio
- Malaria Infection and Immunity Unit Department of Parasites and Insect Vectors Institut Pasteur Paris France
| | - Julianne Mendi Muthinja
- Integrative Parasitology Center for Infectious Diseases Heidelberg University Medical School Heidelberg Germany
| | - Sebastian Weber
- Electron Microscopy Core Facility Heidelberg University Heidelberg Germany
| | - Danny Baltissen
- Integrative Parasitology Center for Infectious Diseases Heidelberg University Medical School Heidelberg Germany
| | - Christopher Lance
- Integrative Parasitology Center for Infectious Diseases Heidelberg University Medical School Heidelberg Germany
| | - Johanna Ripp
- Integrative Parasitology Center for Infectious Diseases Heidelberg University Medical School Heidelberg Germany
| | - Janessa Grech
- Experimental Parasitology Ludwig Maximilian University Munich Planegg‐Martinsried Germany
| | - Markus Meissner
- Experimental Parasitology Ludwig Maximilian University Munich Planegg‐Martinsried Germany
| | - Charlotta Funaya
- Electron Microscopy Core Facility Heidelberg University Heidelberg Germany
| | - Rogerio Amino
- Malaria Infection and Immunity Unit Department of Parasites and Insect Vectors Institut Pasteur Paris France
| | - Friedrich Frischknecht
- Integrative Parasitology Center for Infectious Diseases Heidelberg University Medical School Heidelberg Germany
- German Center for Infection Research (DZIF), Partner Site Heidelberg Heidelberg Germany
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5
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Beyer K, Kracht S, Kehrer J, Singer M, Klug D, Frischknecht F. Limited Plasmodium sporozoite gliding motility in the absence of TRAP family adhesins. Malar J 2021; 20:430. [PMID: 34717635 PMCID: PMC8557484 DOI: 10.1186/s12936-021-03960-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Accepted: 10/19/2021] [Indexed: 12/01/2022] Open
Abstract
Background Plasmodium sporozoites are the highly motile forms of malaria-causing parasites that are transmitted by the mosquito to the vertebrate host. Sporozoites need to enter and cross several cellular and tissue barriers for which they employ a set of surface proteins. Three of these proteins are members of the thrombospondin related anonymous protein (TRAP) family. Here, potential additive, synergistic or antagonistic roles of these adhesion proteins were investigated. Methods Four transgenic Plasmodium berghei parasite lines that lacked two or all three of the TRAP family adhesins TRAP, TLP and TREP were generated using positive–negative selection. The parasite lines were investigated for their capacity to attach to and move on glass, their ability to egress from oocysts and their capacity to enter mosquito salivary glands. One strain was in addition interrogated for its capacity to infect mice. Results The major phenotype of the TRAP single gene deletion dominates additional gene deletion phenotypes. All parasite lines including the one lacking all three proteins were able to conduct some form of active, if unproductive movement. Conclusions The individual TRAP-family adhesins appear to play functionally distinct roles during motility and infection. Other proteins must contribute to substrate adhesion and gliding motility. Graphical Abstract ![]()
Supplementary Information The online version contains supplementary material available at 10.1186/s12936-021-03960-3.
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Affiliation(s)
- Konrad Beyer
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Im Neuenheimer Feld 344, 69120, Heidelberg, Germany
| | - Simon Kracht
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Im Neuenheimer Feld 344, 69120, Heidelberg, Germany
| | - Jessica Kehrer
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Im Neuenheimer Feld 344, 69120, Heidelberg, Germany.,German Center for Infection Research, Partner Site Heidelberg, 69120, Heidelberg, Germany
| | - Mirko Singer
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Im Neuenheimer Feld 344, 69120, Heidelberg, Germany.,Experimental Parasitology, Faculty of Veterinary Medicine, Ludwig-Maximilians-University Munich, Lena-Christ-Straße 48, Planegg, 82152, Munich, Germany
| | - Dennis Klug
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Im Neuenheimer Feld 344, 69120, Heidelberg, Germany.,Université de Strasbourg, CNRS UPR9022, INSERM U963, Institut de Biologie Moléculaire et Cellulaire, 67000, Strasbourg, France
| | - Friedrich Frischknecht
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Im Neuenheimer Feld 344, 69120, Heidelberg, Germany. .,German Center for Infection Research, Partner Site Heidelberg, 69120, Heidelberg, Germany.
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6
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Kimmel J, Kehrer J, Frischknecht F, Spielmann T. Proximity-dependent biotinylation approaches to study apicomplexan biology. Mol Microbiol 2021; 117:553-568. [PMID: 34587292 DOI: 10.1111/mmi.14815] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Accepted: 09/20/2021] [Indexed: 11/28/2022]
Abstract
In the last 10 years, proximity-dependent biotinylation (PDB) techniques greatly expanded the ability to study protein environments in the living cell that range from specific protein complexes to entire compartments. This is achieved by using enzymes such as BirA* and APEX that are fused to proteins of interest and biotinylate proteins in their proximity. PDB techniques are now also increasingly used in apicomplexan parasites. In this review, we first give an overview of the main PDB approaches and how they compare with other techniques that address similar questions. PDB is particularly valuable to detect weak or transient protein associations under physiological conditions and to study cellular structures that are difficult to purify or have a poorly understood protein composition. We also highlight new developments such as novel smaller or faster-acting enzyme variants and conditional PDB approaches, providing improvements in both temporal and spatial resolution which may offer broader application possibilities useful in apicomplexan research. In the second part, we review work using PDB techniques in apicomplexan parasites and how this expanded our knowledge about these medically important parasites.
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Affiliation(s)
- Jessica Kimmel
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - Jessica Kehrer
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany.,German Center for Infectious Disease Research, DZIF, Heidelberg, Germany
| | - Friedrich Frischknecht
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany.,German Center for Infectious Disease Research, DZIF, Heidelberg, Germany
| | - Tobias Spielmann
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
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7
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Ripp J, Kehrer J, Smyrnakou X, Tisch N, Tavares J, Amino R, Ruiz de Almodovar C, Frischknecht F. Malaria parasites differentially sense environmental elasticity during transmission. EMBO Mol Med 2021; 13:e13933. [PMID: 33666362 PMCID: PMC8033522 DOI: 10.15252/emmm.202113933] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 01/28/2021] [Accepted: 01/29/2021] [Indexed: 12/13/2022] Open
Abstract
Transmission of malaria-causing parasites to and by the mosquito relies on active parasite migration and constitutes bottlenecks in the Plasmodium life cycle. Parasite adaption to the biochemically and physically different environments must hence be a key evolutionary driver for transmission efficiency. To probe how subtle but physiologically relevant changes in environmental elasticity impact parasite migration, we introduce 2D and 3D polyacrylamide gels to study ookinetes, the parasite forms emigrating from the mosquito blood meal and sporozoites, the forms transmitted to the vertebrate host. We show that ookinetes adapt their migratory path but not their speed to environmental elasticity and are motile for over 24 h on soft substrates. In contrast, sporozoites evolved more short-lived rapid gliding motility for rapidly crossing the skin. Strikingly, sporozoites are highly sensitive to substrate elasticity possibly to avoid adhesion to soft endothelial cells on their long way to the liver. Hence, the two migratory stages of Plasmodium evolved different strategies to overcome the physical challenges posed by the respective environments and barriers they encounter.
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Affiliation(s)
- Johanna Ripp
- Integrative ParasitologyCenter for Infectious DiseasesHeidelberg University Medical SchoolHeidelbergGermany
| | - Jessica Kehrer
- Integrative ParasitologyCenter for Infectious DiseasesHeidelberg University Medical SchoolHeidelbergGermany
| | - Xanthoula Smyrnakou
- Integrative ParasitologyCenter for Infectious DiseasesHeidelberg University Medical SchoolHeidelbergGermany
- Gene Therapy for Hearing Impairment and DeafnessDepartment of OtolaryngologyHead & Neck SurgeryUniversity of Tübingen Medical CenterTübingenGermany
| | - Nathalie Tisch
- Biochemistry CenterHeidelberg UniversityHeidelbergGermany
- European Center for Angioscience (ECAS)Medical Faculty MannheimHeidelberg UniversityMannheimGermany
| | - Joana Tavares
- IBMC‐Institute for Molecular and Cell Biologyi3S ‐ Institute for Research and Innovation in HealthUniversity of PortoPortoPortugal
- Malaria Infection and Immunity UnitDepartment of Parasites and Insect VectorsInstitut PasteurParisFrance
| | - Rogerio Amino
- Malaria Infection and Immunity UnitDepartment of Parasites and Insect VectorsInstitut PasteurParisFrance
| | - Carmen Ruiz de Almodovar
- Biochemistry CenterHeidelberg UniversityHeidelbergGermany
- European Center for Angioscience (ECAS)Medical Faculty MannheimHeidelberg UniversityMannheimGermany
| | - Friedrich Frischknecht
- Integrative ParasitologyCenter for Infectious DiseasesHeidelberg University Medical SchoolHeidelbergGermany
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8
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Egarter S, Santos JM, Kehrer J, Sattler J, Frischknecht F, Mair GR. Gliding motility protein LIMP promotes optimal mosquito midgut traversal and infection by Plasmodium berghei. Mol Biochem Parasitol 2021; 241:111347. [PMID: 33347893 PMCID: PMC7856051 DOI: 10.1016/j.molbiopara.2020.111347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 12/04/2020] [Accepted: 12/15/2020] [Indexed: 12/02/2022]
Abstract
Substrate-dependent gliding motility is key to malaria transmission. It mediates host cell traversal, invasion and infection by Plasmodium and related apicomplexan parasites. The 110 amino acid-long cell surface protein LIMP is essential for P. berghei sporozoites where it is required for the invasion of the mosquito's salivary glands and the liver cells of the rodent host. Here we define an additional role for LIMP during mosquito invasion by the ookinete. limp mRNA is provided as a translationally repressed mRNP (messenger ribonucleoprotein) by the female gametocyte and the protein translated in the ookinete. Parasites depleted of limp (Δlimp) develop ookinetes with apparent normal morphology and no defect during in vitro gliding motility, and yet display a pronounced reduction in oocyst numbers; compared to wildtype 82 % more Δlimp ookinetes remain within the mosquito blood meal explaining the decrease in oocysts. As in the sporozoite, LIMP exerts a profound role on ookinete infection of the mosquito.
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Affiliation(s)
- Saskia Egarter
- Parasitology, Department of Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
| | - Jorge M Santos
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina da Universidade de Lisboa, Edifício Egas Moniz, Av. Prof. Egas Moniz, Lisbon, Portugal
| | - Jessica Kehrer
- Parasitology, Department of Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
| | - Julia Sattler
- Parasitology, Department of Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
| | - Friedrich Frischknecht
- Parasitology, Department of Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
| | - Gunnar R Mair
- Parasitology, Department of Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany; Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina da Universidade de Lisboa, Edifício Egas Moniz, Av. Prof. Egas Moniz, Lisbon, Portugal; Iowa State University, Biomedical Sciences, Ames, IA, United States.
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9
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De Niz M, Kehrer J, Brancucci NMB, Moalli F, Reynaud EG, Stein JV, Frischknecht F. 3D imaging of undissected optically cleared Anopheles stephensi mosquitoes and midguts infected with Plasmodium parasites. PLoS One 2020; 15:e0238134. [PMID: 32936796 PMCID: PMC7494115 DOI: 10.1371/journal.pone.0238134] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 08/10/2020] [Indexed: 12/21/2022] Open
Abstract
Malaria is a life-threatening disease, caused by Apicomplexan parasites of the Plasmodium genus. The Anopheles mosquito is necessary for the sexual replication of these parasites and for their transmission to vertebrate hosts, including humans. Imaging of the parasite within the insect vector has been attempted using multiple microscopy methods, most of which are hampered by the presence of the light scattering opaque cuticle of the mosquito. So far, most imaging of the Plasmodium mosquito stages depended on either sectioning or surgical dissection of important anatomical sites, such as the midgut and the salivary glands. Optical projection tomography (OPT) and light sheet fluorescence microscopy (LSFM) enable imaging fields of view in the centimeter scale whilst providing micrometer resolution. In this paper, we compare different optical clearing protocols and present reconstructions of the whole body of Plasmodium-infected, optically cleared Anopheles stephensi mosquitoes and their midguts. The 3D-reconstructions from OPT imaging show detailed features of the mosquito anatomy and enable overall localization of parasites in midguts. Additionally, LSFM imaging of mosquito midguts shows detailed distribution of oocysts in extracted midguts. This work was submitted as a pre-print to bioRxiv, available at https://www.biorxiv.org/content/10.1101/682054v2.
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Affiliation(s)
- Mariana De Niz
- Institute of Cell Biology, Heussler Research Group, University of Bern, Bern, Switzerland
| | - Jessica Kehrer
- Center for Infectious Diseases, Integrative Parasitology, Heidelberg University Medical School, Heidelberg, Germany
| | - Nicolas M. B. Brancucci
- Wellcome Centre for Integrative Parasitology, Institute of Infection, Immunity & Inflammation, University of Glasgow, Glasgow, United Kingdom
| | - Federica Moalli
- Theodor Kocher Institute, University of Bern, Bern, Switzerland
| | - Emmanuel G. Reynaud
- School of Biomolecular and Biomedical Science, University College Dublin, Dublin, Ireland
| | - Jens V. Stein
- Department of Oncology, Microbiology and Immunology, University of Fribourg, Fribourg, Switzerland
| | - Friedrich Frischknecht
- Center for Infectious Diseases, Integrative Parasitology, Heidelberg University Medical School, Heidelberg, Germany
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10
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Klug D, Goellner S, Kehrer J, Sattler J, Strauss L, Singer M, Lu C, Springer TA, Frischknecht F. Evolutionarily distant I domains can functionally replace the essential ligand-binding domain of Plasmodium TRAP. eLife 2020; 9:57572. [PMID: 32648541 PMCID: PMC7351488 DOI: 10.7554/elife.57572] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Accepted: 06/25/2020] [Indexed: 02/02/2023] Open
Abstract
Inserted (I) domains function as ligand-binding domains in adhesins that support cell adhesion and migration in many eukaryotic phyla. These adhesins include integrin αβ heterodimers in metazoans and single subunit transmembrane proteins in apicomplexans such as TRAP in Plasmodium and MIC2 in Toxoplasma. Here we show that the I domain of TRAP is essential for sporozoite gliding motility, mosquito salivary gland invasion and mouse infection. Its replacement with the I domain from Toxoplasma MIC2 fully restores tissue invasion and parasite transmission, while replacement with the aX I domain from human integrins still partially restores liver infection. Mutations around the ligand binding site allowed salivary gland invasion but led to inefficient transmission to the rodent host. These results suggest that apicomplexan parasites appropriated polyspecific I domains in part for their ability to engage with multiple ligands and to provide traction for emigration into diverse organs in distant phyla. Malaria is an infectious disease caused by single-celled parasites known as Plasmodium. Humans and other animals with backbones – such as birds, reptiles and rodents – can become hosts for these parasites if an infected female mosquito feeds on their blood. Likewise, healthy mosquitoes can in turn become infected with Plasmodium if they feed on the blood of an infected animal. To complete their life cycle, Plasmodium parasites within a mosquito must become spore-like cells called sporozoites. These sporozoites are highly mobile and can get into the mosquitoes’ salivary glands, meaning they can be passed on to a new host when the insect feeds. During a mosquito bite the sporozoites are spat into the skin of the potential host, where they then need to migrate rapidly to enter the bloodstream. Once in the blood, the sporozoites can then get into liver cells and begin a new infection. One protein called TRAP, which is found on the surface of the sporozoites, is important for their migration and the infection of the salivary glands or liver. Yet it was not known how this happens at the level of the individual proteins involved. Klug et al. have now tested how a part of the TRAP protein, called the I domain, contributes to the infection process. In the experiments, the I domain of TRAP was deleted which showed that the sporozoites need this domain to be able to move around and get into the host tissues. Without the I domain the sporozoites were stuck and could not successfully infect either the mosquitoes, the livers of mice, or human liver cells grown in the laboratory. Klug et al. then replaced the Plasmodium I domain of TRAP with the I domain from a distantly related parasite called Toxoplasma gondii, which causes a condition known as toxoplasmosis. The I domain from Toxoplasma allowed the Plasmodium parasites to infect the host tissues again. This observation was unexpected because Toxoplasma and Plasmodium parasites have evolved separately over the last 800 million years and Toxoplasma does not infect insects. These findings suggest that the I domain of TRAP evolved to bind several other proteins in different tissues and hosts. Future studies will investigate which other parasite proteins TRAP works with to guide sporozoites to the salivary glands or liver. Knowledge of how these proteins act together may lead to new approaches for treating or preventing malaria. For example, some treatments could stop sporozoites from entering liver cells.
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Affiliation(s)
- Dennis Klug
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany.,Université de Strasbourg, CNRS UPR9022, INSERM U963, Institut de Biologie Moléculaire et Cellulaire, Strasbourg, France
| | - Sarah Goellner
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany.,Department of Molecular Virology, Heidelberg University Medical School, Heidelberg, Germany
| | - Jessica Kehrer
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
| | - Julia Sattler
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
| | - Léanne Strauss
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
| | - Mirko Singer
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany.,Experimental Parasitology, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität München, München, Germany
| | - Chafen Lu
- Program in Cellular and Molecular Medicine, Children's Hospital Boston, and Departments of Biological Chemistry and Molecular Pharmacology and of Medicine, Harvard Medical School, Boston, United States
| | - Timothy A Springer
- Program in Cellular and Molecular Medicine, Children's Hospital Boston, and Departments of Biological Chemistry and Molecular Pharmacology and of Medicine, Harvard Medical School, Boston, United States
| | - Friedrich Frischknecht
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
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11
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Kraus M, Weiler N, Oelke D, Kehrer J, Keim DA, Fuchs J. The Impact of Immersion on Cluster Identification Tasks. IEEE Trans Vis Comput Graph 2020; 26:525-535. [PMID: 31536002 DOI: 10.1109/tvcg.2019.2934395] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Recent developments in technology encourage the use of head-mounted displays (HMDs) as a medium to explore visualizations in virtual realities (VRs). VR environments (VREs) enable new, more immersive visualization design spaces compared to traditional computer screens. Previous studies in different domains, such as medicine, psychology, and geology, report a positive effect of immersion, e.g., on learning performance or phobia treatment effectiveness. Our work presented in this paper assesses the applicability of those findings to a common task from the information visualization (InfoVis) domain. We conducted a quantitative user study to investigate the impact of immersion on cluster identification tasks in scatterplot visualizations. The main experiment was carried out with 18 participants in a within-subjects setting using four different visualizations, (1) a 2D scatterplot matrix on a screen, (2) a 3D scatterplot on a screen, (3) a 3D scatterplot miniature in a VRE and (4) a fully immersive 3D scatterplot in a VRE. The four visualization design spaces vary in their level of immersion, as shown in a supplementary study. The results of our main study indicate that task performance differs between the investigated visualization design spaces in terms of accuracy, efficiency, memorability, sense of orientation, and user preference. In particular, the 2D visualization on the screen performed worse compared to the 3D visualizations with regard to the measured variables. The study shows that an increased level of immersion can be a substantial benefit in the context of 3D data and cluster detection.
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Currà C, Kehrer J, Lemgruber L, Silva PAGC, Bertuccini L, Superti F, Pace T, Ponzi M, Frischknecht F, Siden-Kiamos I, Mair GR. Malaria transmission through the mosquito requires the function of the OMD protein. PLoS One 2019; 14:e0222226. [PMID: 31553751 PMCID: PMC6760768 DOI: 10.1371/journal.pone.0222226] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Accepted: 08/23/2019] [Indexed: 11/18/2022] Open
Abstract
Ookinetes, one of the motile and invasive forms of the malaria parasite, rely on gliding motility in order to establish an infection in the mosquito host. Here we characterize the protein PBANKA_0407300 which is conserved in the Plasmodium genus but lacks significant similarity to proteins of other eukaryotes. It is expressed in gametocytes and throughout the invasive mosquito stages of P. berghei, but is absent from asexual blood stages. Mutants lacking the protein developed morphologically normal ookinetes that were devoid of productive motility although some stretching movement could be detected. We therefore named the protein Ookinete Motility Deficient (OMD). Several key factors known to be involved in motility however were normally expressed and localized in the mutant. Importantly, the mutant failed to establish an infection in the mosquito which resulted in a total malaria transmission blockade.
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Affiliation(s)
- Chiara Currà
- Institute of Molecular Biology and Biotechnology, FORTH, Heraklion, Greece
| | - Jessica Kehrer
- Integrative Parasitology, Center for Infectious Diseases, University of Heidelberg Medical School, Heidelberg, Germany
| | - Leandro Lemgruber
- Integrative Parasitology, Center for Infectious Diseases, University of Heidelberg Medical School, Heidelberg, Germany
| | | | - Lucia Bertuccini
- Core Facilities, National Institute of Health, Rome, Italy
- National Center for Innovative Technologies in Public Health, National Institute of Health, Rome, Italy
| | - Fabiana Superti
- Core Facilities, National Institute of Health, Rome, Italy
- National Center for Innovative Technologies in Public Health, National Institute of Health, Rome, Italy
| | - Tomasino Pace
- Department of Infectious Diseases, National Institute of Health, Rome, Italy
| | - Marta Ponzi
- Core Facilities, National Institute of Health, Rome, Italy
- Department of Infectious Diseases, National Institute of Health, Rome, Italy
| | - Friedrich Frischknecht
- Integrative Parasitology, Center for Infectious Diseases, University of Heidelberg Medical School, Heidelberg, Germany
| | - Inga Siden-Kiamos
- Institute of Molecular Biology and Biotechnology, FORTH, Heraklion, Greece
- * E-mail: , (GRM); (IS-K)
| | - Gunnar R. Mair
- Integrative Parasitology, Center for Infectious Diseases, University of Heidelberg Medical School, Heidelberg, Germany
- Instituto Medicina Molecular, Lisbon, Portugal
- Iowa State University, Biomedical Sciences, Ames, Iowa, United States of America
- * E-mail: , (GRM); (IS-K)
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13
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Kumar H, Kehrer J, Singer M, Reinig M, Santos JM, Mair GR, Frischknecht F. Functional genetic evaluation of DNA house-cleaning enzymes in the malaria parasite: dUTPase and Ap4AH are essential in Plasmodium berghei but ITPase and NDH are dispensable. Expert Opin Ther Targets 2019; 23:251-261. [PMID: 30700216 DOI: 10.1080/14728222.2019.1575810] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Accepted: 01/25/2019] [Indexed: 02/06/2023]
Abstract
BACKGROUND Cellular metabolism generates reactive oxygen species. The oxidation and deamination of the deoxynucleoside triphosphate (dNTP) pool results in the formation of non-canonical, toxic dNTPs that can cause mutations, genome instability, and cell death. House-cleaning or sanitation enzymes that break down and detoxify non-canonical nucleotides play major protective roles in nucleotide metabolism and constitute key drug targets for cancer and various pathogens. We hypothesized that owing to their protective roles in nucleotide metabolism, these house-cleaning enzymes are key drug targets in the malaria parasite. METHODS Using the rodent malaria parasite Plasmodium berghei we evaluate here, by gene targeting, a group of conserved proteins with a putative function in the detoxification of non-canonical nucleotides as potential antimalarial drug targets: they are inosine triphosphate pyrophosphatase (ITPase), deoxyuridine triphosphate pyrophosphatase (dUTPase) and two NuDiX hydroxylases, the diadenosine tetraphosphate (Ap4A) hydrolase and the nucleoside triphosphate hydrolase (NDH). RESULTS While all four proteins are expressed constitutively across the intraerythrocytic developmental cycle, neither ITPase nor NDH are required for parasite viability. dutpase and ap4ah null mutants, on the other hand, are not viable suggesting an essential function for these proteins for the malaria parasite. CONCLUSIONS Plasmodium dUTPase and Ap4A could be drug targets in the malaria parasite.
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Affiliation(s)
- Hirdesh Kumar
- a Integrative Parasitology, Department of Infectious Diseases , University of Heidelberg Medical School , Heidelberg , Germany
| | - Jessica Kehrer
- a Integrative Parasitology, Department of Infectious Diseases , University of Heidelberg Medical School , Heidelberg , Germany
| | - Mirko Singer
- a Integrative Parasitology, Department of Infectious Diseases , University of Heidelberg Medical School , Heidelberg , Germany
| | - Miriam Reinig
- a Integrative Parasitology, Department of Infectious Diseases , University of Heidelberg Medical School , Heidelberg , Germany
| | - Jorge M Santos
- b Instituto de Medicina Molecular , Faculdade de Medicina da Universidade de Lisboa , Lisbon , Portugal
| | - Gunnar R Mair
- a Integrative Parasitology, Department of Infectious Diseases , University of Heidelberg Medical School , Heidelberg , Germany
- b Instituto de Medicina Molecular , Faculdade de Medicina da Universidade de Lisboa , Lisbon , Portugal
- c Department of Biomedical Sciences , 2008 College of Veterinary Medicine, Iowa State University , Ames , IA USA
| | - Friedrich Frischknecht
- a Integrative Parasitology, Department of Infectious Diseases , University of Heidelberg Medical School , Heidelberg , Germany
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Klug D, Kehrer J, Frischknecht F, Singer M. A synthetic promoter for multi-stage expression to probe complementary functions of Plasmodium adhesins. J Cell Sci 2018; 131:jcs.210971. [PMID: 30237220 DOI: 10.1242/jcs.210971] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Accepted: 09/10/2018] [Indexed: 11/20/2022] Open
Abstract
Gene expression of malaria parasites is mediated by the apicomplexan Apetala2 (ApiAP2) transcription factor family. Different ApiAP2s control gene expression at distinct stages in the complex life cycle of the parasite, ensuring timely expression of stage-specific genes. ApiAP2s recognize short cis-regulatory elements that are enriched in the upstream/promoter region of their target genes. This should, in principle, allow the generation of 'synthetic' promoters that drive gene expression at desired stages of the Plasmodium life cycle. Here we test this concept by combining cis-regulatory elements of two genes expressed successively within the mosquito part of the life cycle. Our tailored 'synthetic' promoters, named Spooki 1.0 and Spooki 2.0, activate gene expression in early and late mosquito stages, as shown by the expression of a fluorescent reporter. We used these promoters to address the specific functionality of two related adhesins that are exclusively expressed either during the early or late mosquito stage. By modifying the expression profile of both adhesins in absence of their counterpart we were able to test for complementary functions in gliding and invasion. We discuss the possible advantages and drawbacks of our approach.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Dennis Klug
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
| | - Jessica Kehrer
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
| | - Friedrich Frischknecht
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
| | - Mirko Singer
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
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15
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Kehrer J, Kuss C, Andres-Pons A, Reustle A, Dahan N, Devos D, Kudryashev M, Beck M, Mair GR, Frischknecht F. Nuclear Pore Complex Components in the Malaria Parasite Plasmodium berghei. Sci Rep 2018; 8:11249. [PMID: 30050042 PMCID: PMC6062611 DOI: 10.1038/s41598-018-29590-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Accepted: 06/08/2018] [Indexed: 12/13/2022] Open
Abstract
The nuclear pore complex (NPC) is a large macromolecular assembly of around 30 different proteins, so-called nucleoporins (Nups). Embedded in the nuclear envelope the NPC mediates bi-directional exchange between the cytoplasm and the nucleus and plays a role in transcriptional regulation that is poorly understood. NPCs display modular arrangements with an overall structure that is generally conserved among many eukaryotic phyla. However, Nups of yeast or human origin show little primary sequence conservation with those from early-branching protozoans leaving those of the malaria parasite unrecognized. Here we have combined bioinformatic and genetic methods to identify and spatially characterize Nup components in the rodent infecting parasite Plasmodium berghei and identified orthologs from the human malaria parasite P. falciparum, as well as the related apicomplexan parasite Toxoplasma gondii. For the first time we show the localization of selected Nups throughout the P. berghei life cycle. Largely restricted to apicomplexans we identify an extended C-terminal poly-proline extension in SEC13 that is essential for parasite survival and provide high-resolution images of Plasmodium NPCs obtained by cryo electron tomography. Our data provide the basis for full characterization of NPCs in malaria parasites, early branching unicellular eukaryotes with significant impact on human health.
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Affiliation(s)
- Jessica Kehrer
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Im Neuenheimer Feld 344, 69120, Heidelberg, Germany
| | - Claudia Kuss
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Im Neuenheimer Feld 344, 69120, Heidelberg, Germany
| | - Amparo Andres-Pons
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117, Heidelberg, Germany
| | - Anna Reustle
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Im Neuenheimer Feld 344, 69120, Heidelberg, Germany
| | - Noa Dahan
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Im Neuenheimer Feld 344, 69120, Heidelberg, Germany
| | - Damien Devos
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117, Heidelberg, Germany.,Centro Andaluz de Biología del Desarrollo CABD, Universidad Pablo de Olavide-CSIC, Carretera de Utrera, 41013, Sevilla, Spain
| | - Mikhail Kudryashev
- Max Planck Institute of Biophysics, Max-von-Laue Str. 3, 60438, Frankfurt am Main, Germany.,Buchmann Institute for Molecular Life Sciences, Goethe University of Frankfurt, Max-von-Laue Str. 17, 60438, Frankfurt am Main, Germany
| | - Martin Beck
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117, Heidelberg, Germany
| | - Gunnar R Mair
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Im Neuenheimer Feld 344, 69120, Heidelberg, Germany. .,Iowa State University, Biomedical Sciences, College of Veterinary Medicine, 1800 Christensen Drive, Ames, IA, 50011, USA.
| | - Friedrich Frischknecht
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Im Neuenheimer Feld 344, 69120, Heidelberg, Germany.
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16
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Hallée S, Thériault C, Gagnon D, Kehrer J, Frischknecht F, Mair GR, Richard D. Identification of a Golgi apparatus protein complex important for the asexual erythrocytic cycle of the malaria parasite Plasmodium falciparum. Cell Microbiol 2018; 20:e12843. [PMID: 29579782 DOI: 10.1111/cmi.12843] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 03/09/2018] [Accepted: 03/09/2018] [Indexed: 12/01/2022]
Abstract
Compared with other eukaryotic cell types, malaria parasites appear to possess a more rudimentary Golgi apparatus being composed of dispersed, unstacked cis and trans-cisternae. Despite playing a central role in the secretory pathway of the parasite, few Plasmodium Golgi resident proteins have been characterised. We had previously identified a new Golgi resident protein of unknown function, which we had named Golgi Protein 1, and now show that it forms a complex with a previously uncharacterised transmembrane protein (Golgi Protein 2, GP2). The Golgi Protein complex localises to the cis-Golgi throughout the erythrocytic cycle and potentially also during the mosquito stages. Analysis of parasite strains where GP1 expression is conditionally repressed and/or the GP2 gene is inactivated reveals that though the Golgi protein complex is not essential at any stage of the parasite life cycle, it is important for optimal asexual development in the blood stages.
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Affiliation(s)
- Stéphanie Hallée
- Centre de recherche en infectiologie, CHU de Québec-Université Laval, Quebec City, Quebec, Canada
| | - Catherine Thériault
- Centre de recherche en infectiologie, CHU de Québec-Université Laval, Quebec City, Quebec, Canada
| | - Dominic Gagnon
- Centre de recherche en infectiologie, CHU de Québec-Université Laval, Quebec City, Quebec, Canada
| | - Jessica Kehrer
- Integrative Parasitology, Department of Infectious Diseases, University of Heidelberg Medical School, Heidelberg, Germany
| | - Friedrich Frischknecht
- Integrative Parasitology, Department of Infectious Diseases, University of Heidelberg Medical School, Heidelberg, Germany
| | - Gunnar R Mair
- Integrative Parasitology, Department of Infectious Diseases, University of Heidelberg Medical School, Heidelberg, Germany
| | - Dave Richard
- Centre de recherche en infectiologie, CHU de Québec-Université Laval, Quebec City, Quebec, Canada
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17
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Moreau CA, Bhargav SP, Kumar H, Quadt KA, Piirainen H, Strauss L, Kehrer J, Streichfuss M, Spatz JP, Wade RC, Kursula I, Frischknecht F. A unique profilin-actin interface is important for malaria parasite motility. PLoS Pathog 2017; 13:e1006412. [PMID: 28552953 PMCID: PMC5464670 DOI: 10.1371/journal.ppat.1006412] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Revised: 06/08/2017] [Accepted: 05/16/2017] [Indexed: 11/30/2022] Open
Abstract
Profilin is an actin monomer binding protein that provides ATP-actin for incorporation into actin filaments. In contrast to higher eukaryotic cells with their large filamentous actin structures, apicomplexan parasites typically contain only short and highly dynamic microfilaments. In apicomplexans, profilin appears to be the main monomer-sequestering protein. Compared to classical profilins, apicomplexan profilins contain an additional arm-like β-hairpin motif, which we show here to be critically involved in actin binding. Through comparative analysis using two profilin mutants, we reveal this motif to be implicated in gliding motility of Plasmodium berghei sporozoites, the rapidly migrating forms of a rodent malaria parasite transmitted by mosquitoes. Force measurements on migrating sporozoites and molecular dynamics simulations indicate that the interaction between actin and profilin fine-tunes gliding motility. Our data suggest that evolutionary pressure to achieve efficient high-speed gliding has resulted in a unique profilin-actin interface in these parasites. The malaria parasite Plasmodium has two invasive forms that migrate across different tissue barriers, the ookinete and the very rapidly migrating sporozoite. Previous work has shown that the motility of these and related parasites (e.g. Toxoplasma gondii) depends on a highly dynamic actin cytoskeleton and retrograde flow of surface adhesins. These unusual actin dynamics are due to the divergent structure of protozoan actins and the actions of actin-binding proteins, which can have non-canonical functions in these parasites. Profilin is one of the most important and most investigated actin-binding proteins, which binds ADP-actin and catalyzes ADP-ATP exchange to then promote actin polymerization. Parasite profilins bind monomeric actin and contain an additional domain compared to canonical profilins. Here we show that this additional domain of profilin is critical for actin binding and rapid sporozoite motility but has little impact on the slower ookinete. Sporozoites of a parasite line carrying mutations in this domain cannot translate force production and retrograde flow into optimal parasite motility. Using molecular dynamics simulations, we find that differences between mutant parasites in their capacity to migrate can be traced back to a single hydrogen bond at the actin-profilin interface.
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Affiliation(s)
- Catherine A. Moreau
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
| | - Saligram P. Bhargav
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
- Biocenter Oulu and Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
| | - Hirdesh Kumar
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
- Molecular and Cellular Modeling Group, Heidelberg Institute for Theoretical Studies (HITS), Heidelberg, Germany
| | - Katharina A. Quadt
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
- Institute for Physical Chemistry, Biophysical Chemistry, Heidelberg University, Heidelberg, Germany
| | - Henni Piirainen
- Biocenter Oulu and Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
| | - Léanne Strauss
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
| | - Jessica Kehrer
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
| | - Martin Streichfuss
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
- Institute for Physical Chemistry, Biophysical Chemistry, Heidelberg University, Heidelberg, Germany
| | - Joachim P. Spatz
- Institute for Physical Chemistry, Biophysical Chemistry, Heidelberg University, Heidelberg, Germany
- Department of Cellular Biophysics, Max-Planck Institute for Medical Research, Heidelberg, Germany
| | - Rebecca C. Wade
- Molecular and Cellular Modeling Group, Heidelberg Institute for Theoretical Studies (HITS), Heidelberg, Germany
- Center for Molecular Biology (ZMBH), DKFZ-ZMBH Alliance and Interdisciplinary Center for Scientific Computing (IWR), Heidelberg University, Heidelberg, Germany
| | - Inari Kursula
- Biocenter Oulu and Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
- Department of Biomedicine, University of Bergen, Bergen, Norway
- * E-mail: (IK); (FF)
| | - Friedrich Frischknecht
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
- * E-mail: (IK); (FF)
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18
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Santos JM, Egarter S, Zuzarte-Luís V, Kumar H, Moreau CA, Kehrer J, Pinto A, da Costa M, Franke-Fayard B, Janse CJ, Frischknecht F, Mair GR. Malaria parasite LIMP protein regulates sporozoite gliding motility and infectivity in mosquito and mammalian hosts. eLife 2017; 6:e24109. [PMID: 28525314 PMCID: PMC5438254 DOI: 10.7554/elife.24109] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Accepted: 04/29/2017] [Indexed: 12/11/2022] Open
Abstract
Gliding motility allows malaria parasites to migrate and invade tissues and cells in different hosts. It requires parasite surface proteins to provide attachment to host cells and extracellular matrices. Here, we identify the Plasmodium protein LIMP (the name refers to a gliding phenotype in the sporozoite arising from epitope tagging of the endogenous protein) as a key regulator for adhesion during gliding motility in the rodent malaria model P. berghei. Transcribed in gametocytes, LIMP is translated in the ookinete from maternal mRNA, and later in the sporozoite. The absence of LIMP reduces initial mosquito infection by 50%, impedes salivary gland invasion 10-fold, and causes a complete absence of liver invasion as mutants fail to attach to host cells. GFP tagging of LIMP caused a limping defect during movement with reduced speed and transient curvature changes of the parasite. LIMP is an essential motility and invasion factor necessary for malaria transmission.
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Affiliation(s)
- Jorge M Santos
- Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, Edifício Egas Moniz, Av. Prof. Egas Moniz, Lisbon, Portugal
| | - Saskia Egarter
- Parasitology, Department of Infectious Diseases, University of Heidelberg Medical School, Heidelberg, Germany
| | - Vanessa Zuzarte-Luís
- Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, Edifício Egas Moniz, Av. Prof. Egas Moniz, Lisbon, Portugal
| | - Hirdesh Kumar
- Parasitology, Department of Infectious Diseases, University of Heidelberg Medical School, Heidelberg, Germany
- Kusuma School of Biological Sciences, Indian Institute of Technology Delhi, New Delhi, India
| | - Catherine A Moreau
- Parasitology, Department of Infectious Diseases, University of Heidelberg Medical School, Heidelberg, Germany
| | - Jessica Kehrer
- Parasitology, Department of Infectious Diseases, University of Heidelberg Medical School, Heidelberg, Germany
| | - Andreia Pinto
- Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, Edifício Egas Moniz, Av. Prof. Egas Moniz, Lisbon, Portugal
| | - Mário da Costa
- Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, Edifício Egas Moniz, Av. Prof. Egas Moniz, Lisbon, Portugal
| | - Blandine Franke-Fayard
- Leiden Malaria Research Group, Department of Parasitology, Leiden University Medical Center, Leiden, The Netherlands
| | - Chris J Janse
- Leiden Malaria Research Group, Department of Parasitology, Leiden University Medical Center, Leiden, The Netherlands
| | - Friedrich Frischknecht
- Parasitology, Department of Infectious Diseases, University of Heidelberg Medical School, Heidelberg, Germany
| | - Gunnar R Mair
- Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, Edifício Egas Moniz, Av. Prof. Egas Moniz, Lisbon, Portugal
- Parasitology, Department of Infectious Diseases, University of Heidelberg Medical School, Heidelberg, Germany
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Kehrer J, Singer M, Lemgruber L, Silva PAGC, Frischknecht F, Mair GR. A Putative Small Solute Transporter Is Responsible for the Secretion of G377 and TRAP-Containing Secretory Vesicles during Plasmodium Gamete Egress and Sporozoite Motility. PLoS Pathog 2016; 12:e1005734. [PMID: 27427910 PMCID: PMC4948853 DOI: 10.1371/journal.ppat.1005734] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2016] [Accepted: 06/08/2016] [Indexed: 11/18/2022] Open
Abstract
Regulated protein secretion is required for malaria parasite life cycle progression and transmission between the mammalian host and mosquito vector. During transmission from the host to the vector, exocytosis of highly specialised secretory vesicles, such as osmiophilic bodies, is key to the dissolution of the red blood cell and parasitophorous vacuole membranes enabling gamete egress. The positioning of adhesins from the TRAP family, from micronemes to the sporozoite surface, is essential for gliding motility of the parasite and transmission from mosquito to mammalian host. Here we identify a conserved role for the putative pantothenate transporter PAT in Plasmodium berghei in vesicle fusion of two distinct classes of vesicles in gametocytes and sporozoites. PAT is a membrane component of osmiophilic bodies in gametocytes and micronemes in sporozoites. Despite normal formation and trafficking of osmiophilic bodies to the cell surface upon activation, PAT-deficient gametes fail to discharge their contents, remain intraerythrocytic and unavailable for fertilisation and further development in the mosquito. Sporozoites lacking PAT fail to secrete TRAP, are immotile and thus unable to infect the subsequent rodent host. Thus, P. berghei PAT appears to regulate exocytosis in two distinct populations of vesicles in two different life cycle forms rather than acting as pantothenic transporter during parasite transmission. Transmission of the malaria parasite between mosquito and host requires two different life cycle stages—the gametocyte and the sporozoite. In both parasite forms, transmission is dependent on exocytosis of stage-specific vesicles. In gametocytes these vesicles release proteins allowing egress from red blood cells and fertilization, and are hence needed to establish an infection in the mosquito. In contrast, proteins are secreted into the membrane of the sporozoite, where they play distinct roles during adhesion and motility, both crucial for transmission back into the mammalian host. Here we show that parasites lacking the putative small solute transporter PAT are still able to form vesicles in both parasite forms but are unable to fuse and secrete their contents. This results in impaired parasite transmission into and from the mosquito. Our work shows that a single protein can regulate the function of functionally distinct classes of vesicles in different life cycle forms of a parasite.
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Affiliation(s)
- Jessica Kehrer
- Integrative Parasitology, Center for Infectious Diseases, University of Heidelberg Medical School, Heidelberg, Germany
| | - Mirko Singer
- Integrative Parasitology, Center for Infectious Diseases, University of Heidelberg Medical School, Heidelberg, Germany
| | - Leandro Lemgruber
- Integrative Parasitology, Center for Infectious Diseases, University of Heidelberg Medical School, Heidelberg, Germany
| | | | - Friedrich Frischknecht
- Integrative Parasitology, Center for Infectious Diseases, University of Heidelberg Medical School, Heidelberg, Germany
- * E-mail: (FF); ; (GRM)
| | - Gunnar R. Mair
- Integrative Parasitology, Center for Infectious Diseases, University of Heidelberg Medical School, Heidelberg, Germany
- Instituto Medicina Molecular, Lisbon, Portugal
- * E-mail: (FF); ; (GRM)
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Bane KS, Lepper S, Kehrer J, Sattler JM, Singer M, Reinig M, Klug D, Heiss K, Baum J, Mueller AK, Frischknecht F. The Actin Filament-Binding Protein Coronin Regulates Motility in Plasmodium Sporozoites. PLoS Pathog 2016; 12:e1005710. [PMID: 27409081 PMCID: PMC4943629 DOI: 10.1371/journal.ppat.1005710] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Accepted: 05/26/2016] [Indexed: 11/21/2022] Open
Abstract
Parasites causing malaria need to migrate in order to penetrate tissue barriers and enter host cells. Here we show that the actin filament-binding protein coronin regulates gliding motility in Plasmodium berghei sporozoites, the highly motile forms of a rodent malaria-causing parasite transmitted by mosquitoes. Parasites lacking coronin show motility defects that impair colonization of the mosquito salivary glands but not migration in the skin, yet result in decreased transmission efficiency. In non-motile sporozoites low calcium concentrations mediate actin-independent coronin localization to the periphery. Engagement of extracellular ligands triggers an intracellular calcium release followed by the actin-dependent relocalization of coronin to the rear and initiation of motility. Mutational analysis and imaging suggest that coronin organizes actin filaments for productive motility. Using coronin-mCherry as a marker for the presence of actin filaments we found that protein kinase A contributes to actin filament disassembly. We finally speculate that calcium and cAMP-mediated signaling regulate a switch from rapid parasite motility to host cell invasion by differentially influencing actin dynamics. Parasites causing malaria are transmitted by mosquitoes and need to migrate to cross tissue barriers. The form of the parasite transmitted by the mosquito, the so-called sporozoite, needs motility to enter the salivary glands, to migrate within the skin and to enter into blood capillaries and eventually hepatocytes, where the parasites differentiate into thousands of merozoites that invade red blood cells. Sporozoite motility is based on an actin-myosin motor, as is the case in many other eukaryotic cells. However, most eukaryotic cells move much slower than sporozoites. How these parasites reach their high speed is not clear but current evidence suggests that actin filaments need to be organized by either actin-binding proteins or membrane proteins that link the filaments to an extracellular substrate. The present study explores the role of the actin filament-binding protein coronin in the motility of sporozoites of the rodent model parasite Plasmodium berghei. We found that the deletion of P. berghei coronin leads to defects in parasite motility and thus lower infection of mosquito salivary glands, which translates into less efficient transmission of the parasites. Our experiments suggest that coronin organizes actin filaments to achieve rapid and directional motility. We also identify two signaling pathways that converge to regulate actin filament dynamics and suggest that they play a role in switching the parasite from its motility mode to a cell invasion mode.
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Affiliation(s)
- Kartik S. Bane
- Integrative Parasitology, Center for Infectious Diseases, University of Heidelberg Medical School, Heidelberg, Germany
| | - Simone Lepper
- Integrative Parasitology, Center for Infectious Diseases, University of Heidelberg Medical School, Heidelberg, Germany
| | - Jessica Kehrer
- Integrative Parasitology, Center for Infectious Diseases, University of Heidelberg Medical School, Heidelberg, Germany
| | - Julia M. Sattler
- Integrative Parasitology, Center for Infectious Diseases, University of Heidelberg Medical School, Heidelberg, Germany
| | - Mirko Singer
- Integrative Parasitology, Center for Infectious Diseases, University of Heidelberg Medical School, Heidelberg, Germany
| | - Miriam Reinig
- Integrative Parasitology, Center for Infectious Diseases, University of Heidelberg Medical School, Heidelberg, Germany
| | - Dennis Klug
- Integrative Parasitology, Center for Infectious Diseases, University of Heidelberg Medical School, Heidelberg, Germany
| | - Kirsten Heiss
- Parasitology, Center for Infectious Diseases, University of Heidelberg Medical School, Heidelberg, Germany
- Malva GmbH, Heidelberg, Germany
| | - Jake Baum
- Department of Life Sciences, Imperial College London, London, United Kingdom
| | - Ann-Kristin Mueller
- Parasitology, Center for Infectious Diseases, University of Heidelberg Medical School, Heidelberg, Germany
| | - Friedrich Frischknecht
- Integrative Parasitology, Center for Infectious Diseases, University of Heidelberg Medical School, Heidelberg, Germany
- * E-mail:
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Kehrer J, Frischknecht F, Mair GR. Proteomic Analysis of the Plasmodium berghei Gametocyte Egressome and Vesicular bioID of Osmiophilic Body Proteins Identifies Merozoite TRAP-like Protein (MTRAP) as an Essential Factor for Parasite Transmission. Mol Cell Proteomics 2016; 15:2852-62. [PMID: 27371728 DOI: 10.1074/mcp.m116.058263] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Indexed: 01/08/2023] Open
Abstract
Malaria transmission from an infected host to the mosquito vector requires the uptake of intraerythrocytic sexual precursor cells into the mosquito midgut. For the release of mature extracellular gametes two membrane barriers-the parasite parasitophorous vacuole membrane and the host red blood cell membrane-need to be dissolved. Membrane lysis occurs after the release of proteins from specialized secretory vesicles including osmiophilic bodies. In this study we conducted proteomic analyses of the P. berghei gametocyte egressome and developed a vesicular bioID approach to identify hitherto unknown proteins with a potential function in gametocyte egress. This first Plasmodium gametocyte egressome includes the proteins released by the parasite during the lysis of the parasitophorous vacuole membrane and red blood cell membrane. BioID of the osmiophilic body protein MDV1/PEG3 revealed a vesicular proteome of these gametocyte-specific secretory vesicles. Fluorescent protein tagging and gene deletion approaches were employed to validate and identify a set of novel factors essential for this lysis and egress process. Our study provides the first in vivo bioID for a rodent malaria parasite and together with the first Plasmodium gametocyte egressome identifies MTRAP as a novel factor essential for mosquito transmission. Our data provide an important resource for proteins potentially involved in a key step of gametogenesis.
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Affiliation(s)
- Jessica Kehrer
- From the ‡Integrative Parasitology, Center for Infectious Diseases, University of Heidelberg Medical School, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
| | - Friedrich Frischknecht
- From the ‡Integrative Parasitology, Center for Infectious Diseases, University of Heidelberg Medical School, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
| | - Gunnar R Mair
- From the ‡Integrative Parasitology, Center for Infectious Diseases, University of Heidelberg Medical School, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
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Santos JM, Kehrer J, Franke-Fayard B, Frischknecht F, Janse CJ, Mair GR. The Plasmodium palmitoyl-S-acyl-transferase DHHC2 is essential for ookinete morphogenesis and malaria transmission. Sci Rep 2015; 5:16034. [PMID: 26526684 PMCID: PMC4630622 DOI: 10.1038/srep16034] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Accepted: 10/08/2015] [Indexed: 12/20/2022] Open
Abstract
The post-translational addition of C-16 long chain fatty acids to protein cysteine residues is catalysed by palmitoyl-S-acyl-transferases (PAT) and affects the affinity of a modified protein for membranes and therefore its subcellular localisation. In apicomplexan parasites this reversible protein modification regulates numerous biological processes and specifically affects cell motility, and invasion of host cells by Plasmodium falciparum merozoites and Toxoplasma gondii tachyzoites. Using inhibitor studies we show here that palmitoylation is key to transformation of zygotes into ookinetes during initial mosquito infection with P. berghei. We identify DHHC2 as a unique PAT mediating ookinete formation and morphogenesis. Essential for life cycle progression in asexual blood stage parasites and thus refractory to gene deletion analyses, we used promoter swap (ps) methodology to maintain dhhc2 expression in asexual blood stages but down regulate expression in sexual stage parasites and during post-fertilization development of the zygote. The ps mutant showed normal gamete formation, fertilisation and DNA replication to tetraploid cells, but was characterised by a complete block in post-fertilisation development and ookinete formation. Our report highlights the crucial nature of the DHHC2 palmitoyl-S-acyltransferase for transmission of the malaria parasite to the mosquito vector through its essential role for ookinete morphogenesis.
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Affiliation(s)
- Jorge M Santos
- Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, Edifício Egas Moniz, Av. Prof. Egas Moniz, 1649-028 Lisbon, Portugal
| | - Jessica Kehrer
- Parasitology, Department of Infectious Diseases, University of Heidelberg Medical School, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
| | - Blandine Franke-Fayard
- Leiden Malaria Research Group, Department of Parasitology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
| | - Friedrich Frischknecht
- Parasitology, Department of Infectious Diseases, University of Heidelberg Medical School, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
| | - Chris J Janse
- Leiden Malaria Research Group, Department of Parasitology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
| | - Gunnar R Mair
- Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, Edifício Egas Moniz, Av. Prof. Egas Moniz, 1649-028 Lisbon, Portugal.,Parasitology, Department of Infectious Diseases, University of Heidelberg Medical School, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
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Seidel A, Hess MP, Kehrer J, Schafer W, Kufner M, Siccardi M, Cacciapuoti L, Sanches IA, Feltham S. The ACES Microwave Link: Instrument Design and Test Results. ACTA ACUST UNITED AC 2007. [DOI: 10.1109/freq.2007.4319285] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Kehrer J, Dekant W. Editorial comment. Toxicol Lett 1997. [DOI: 10.1016/s0378-4274(97)90000-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Friedl R, Wieshammer S, Kehrer J, Ammon C, Hübner D, Lehmann J, Heimpel H. [A case-based and multi-media computer learning program on the topic of myocardial infarct, angina pectoris and mitral valve stenosis]. Med Klin (Munich) 1996; 91:564-9. [PMID: 8984314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
BACKGROUND Principles in the field of cognitive psychology and problem-based learning together with recent progress in multimedia technologies are providing the basis for the development of case-based and computer-assisted learning systems. With reference to the information-overload of theoretical and factual knowledge in medical education these programs can be an efficient tool to satisfy the current need for new, practical, skill-related forms of knowledge transfer. METHODS Apple-Macintosh Computers were selected to develop interactive, multimedia patient-simulations on mitral stenosis, angina pectoris and myocardial infarction. INSTRUCTIONAL AIM AND CONTENTS The user acquires knowledge and skills about the leading symptoms, differential diagnoses, the use and analysis of laboratory examinations and the process of diagnostic reasoning while working through the computer-simulated cases. PEDAGOGICAL DESIGN AND CONCLUSION Important pedagogical principles associated with computer-assisted learning were employed in the program. Clinical situations can be simulated repeatedly and for every student in an authentic manner. Therefore the program can serve as a preparation for and a supplement to practical clinical education. Compared to conventional teaching media the development of instructional multimedia software requires a tremendous amount of time and resources. Thus, controlled studies are important to objectify the overall advantages such programs can have.
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Affiliation(s)
- R Friedl
- Abteilung Innere Medicine III, Universität Ulm
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