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Collier S, Pietsch E, Dans M, Ling D, Tavella TA, Lopaticki S, Marapana DS, Shibu MA, Andrew D, Tiash S, McMillan PJ, Gilson P, Tilley L, Dixon MWA. Plasmodium falciparum formins are essential for invasion and sexual stage development. Commun Biol 2023; 6:861. [PMID: 37596377 PMCID: PMC10439200 DOI: 10.1038/s42003-023-05233-y] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Accepted: 08/09/2023] [Indexed: 08/20/2023] Open
Abstract
The malaria parasite uses actin-based mechanisms throughout its lifecycle to control a range of biological processes including intracellular trafficking, gene regulation, parasite motility and invasion. In this work we assign functions to the Plasmodium falciparum formins 1 and 2 (FRM1 and FRM2) proteins in asexual and sexual blood stage development. We show that FRM1 is essential for merozoite invasion and FRM2 is required for efficient cell division. We also observed divergent functions for FRM1 and FRM2 in gametocyte development. Conditional deletion of FRM1 leads to a delay in gametocyte stage progression. We show that FRM2 controls the actin and microtubule cytoskeletons in developing gametocytes, with premature removal of the protein resulting in a loss of transmissible stage V gametocytes. Lastly, we show that targeting formin proteins with the small molecule inhibitor of formin homology domain 2 (SMIFH2) leads to a multistage block in asexual and sexual stage parasite development.
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Affiliation(s)
- Sophie Collier
- Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, VIC, 3010, Australia
- Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Emma Pietsch
- Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, VIC, 3010, Australia
- Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Madeline Dans
- The Macfarlane Burnet Institute for Medical Research, 85 Commercial Road, Melbourne, VIC, 3004, Australia
| | - Dawson Ling
- The Macfarlane Burnet Institute for Medical Research, 85 Commercial Road, Melbourne, VIC, 3004, Australia
| | - Tatyana A Tavella
- Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, VIC, 3010, Australia
- Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Sash Lopaticki
- Department of Infectious Diseases, Doherty Institute, University of Melbourne, Parkville, VIC, 3010, Australia
- Walter and Eliza Hall Institute, 1G Royal Parade, Parkville, VIC, 3052, Australia
| | - Danushka S Marapana
- Walter and Eliza Hall Institute, 1G Royal Parade, Parkville, VIC, 3052, Australia
| | - Mohini A Shibu
- Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, VIC, 3010, Australia
- Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Dean Andrew
- Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, VIC, 3010, Australia
- Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Snigdha Tiash
- Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, VIC, 3010, Australia
- Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Paul J McMillan
- Biological Optical Microscopy Platform, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Paul Gilson
- The Macfarlane Burnet Institute for Medical Research, 85 Commercial Road, Melbourne, VIC, 3004, Australia
| | - Leann Tilley
- Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, VIC, 3010, Australia
- Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Matthew W A Dixon
- Department of Infectious Diseases, Doherty Institute, University of Melbourne, Parkville, VIC, 3010, Australia.
- Walter and Eliza Hall Institute, 1G Royal Parade, Parkville, VIC, 3052, Australia.
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2
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Bajelan S, Bahreini MS, Asgari Q, Mikaeili F. Viability and infectivity of Toxoplasma gondii tachyzoites exposed to Butanedione monoxime. J Parasit Dis 2020; 44:822-828. [PMID: 32837055 PMCID: PMC7430933 DOI: 10.1007/s12639-020-01259-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Accepted: 08/05/2020] [Indexed: 12/17/2022] Open
Abstract
The most important pathogenesis factor in the Apicomplexa parasites is invasion to the host cell. Given the inhibitory role of Butanedione Monoxime (BDM) on myosin-actin interaction, this study aimed to investigate the effects of this molecule on the vitality and infectivity of Toxoplasma tachyzoites in order to provide a new option for vaccine development. The tachyzoites of the RH strain of Toxoplasma gondii were exposed to different concentrations (1, 2, 4, 8, 16, 32, 64, and 128 μg/mL) of BDM, and mortality effect was assessed by flow cytometry. Then, the penetration ability of the tachyzoites was investigated in HeLa and macrophage cell lines. The infectivity of exposed tachyzoites to BDM were also investigated in mice through following up and detecting the etiological factor. The highest percentage of mortality (72.69%) was seen in the tachyzoites exposed to 128 μg/mL of the compound. The tachyzoites exposed to 32, 64, and 128 μg/mL of BDM began the proliferation in HeLa cells after 48 h, while this proliferation was initiated within 24 h in macrophage cells. All the mice inoculated with the BDM-treated tachyzoites died after 13 days. The mean survival time of the mice receiving tachyzoites exposed to 128 μg/mL of BDM was 12.4 days, which was significantly different from the negative control group (p = 0.001). BDM, as the inhibitor of myosin-actin interaction, and other substances that block the entry of parasites into cells may be suitable candidates for vaccine production against Toxoplasma. Yet, future studies are required to be conducted on the issue.
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Affiliation(s)
- Sara Bajelan
- Department of Parasitology and Mycology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Mohammad Saleh Bahreini
- Department of Parasitology and Mycology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Qasem Asgari
- Department of Parasitology and Mycology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Fattaneh Mikaeili
- Department of Parasitology and Mycology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
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3
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Siden-Kiamos I, Goosmann C, Buscaglia CA, Brinkmann V, Matuschewski K, Montagna GN. Polarization of MTIP is a signature of gliding locomotion in Plasmodium ookinetes and sporozoites. Mol Biochem Parasitol 2019; 235:111247. [PMID: 31874192 DOI: 10.1016/j.molbiopara.2019.111247] [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] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 12/16/2019] [Accepted: 12/19/2019] [Indexed: 11/17/2022]
Abstract
Gliding motility and cell invasion are essential for the successful transmission of Plasmodium parasites. These processes rely on an acto-myosin motor located underneath the parasite plasma membrane. The Myosin A-tail interacting protein (MTIP) connects the class XIV myosin A (MyoA) to the gliding-associated proteins and is essential for assembly of the motor at the inner membrane complex. Here, we assessed the subcellular localization of MTIP in Plasmodium berghei motile stages from wild-type parasites and mutants that lack MyoA or the small heat shock protein 20 (HSP20). We demonstrate that MTIP is recruited to the apical end of motile ookinetes independently of the presence of MyoA. We also show that infective sporozoites displayed a polarized MTIP distribution during gliding, and that this distribution was abrogated in mutant parasites with an aberrant locomotion.
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Affiliation(s)
- Inga Siden-Kiamos
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology, Hellas, 700 13 Heraklion, Crete, Greece
| | | | - Carlos A Buscaglia
- Instituto de Investigaciones Biotecnológicas 'Dr Rodolfo Ugalde' (IIBio), UNSAM-CONICET, 1650 San Martín, Buenos Aires, Argentina
| | - Volker Brinkmann
- Max Planck Institute for Infection Biology, 10117 Berlin, Germany
| | - Kai Matuschewski
- Max Planck Institute for Infection Biology, 10117 Berlin, Germany; Department of Molecular Parasitology, Institute of Biology, Humboldt University, 10117 Berlin, Germany
| | - Georgina N Montagna
- Max Planck Institute for Infection Biology, 10117 Berlin, Germany; Instituto de Investigaciones Biotecnológicas 'Dr Rodolfo Ugalde' (IIBio), UNSAM-CONICET, 1650 San Martín, Buenos Aires, Argentina; Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo, 049032, SP, Brazil..
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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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5
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Govindasamy K, Khan R, Snyder M, Lou HJ, Du P, Kudyba HM, Muralidharan V, Turk BE, Bhanot P. Plasmodium falciparum Cyclic GMP-Dependent Protein Kinase Interacts with a Subunit of the Parasite Proteasome. Infect Immun 2019; 87:e00523-18. [PMID: 30323024 DOI: 10.1128/IAI.00523-18] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Accepted: 09/29/2018] [Indexed: 12/20/2022] Open
Abstract
Malaria is caused by the protozoan parasite Plasmodium, which undergoes a complex life cycle in a human host and a mosquito vector. The parasite's cyclic GMP (cGMP)-dependent protein kinase (PKG) is essential at multiple steps of the life cycle. Phosphoproteomic studies in Plasmodium falciparum erythrocytic stages and Plasmodium berghei ookinetes have identified proteolysis as a major biological pathway dependent on PKG activity. To further understand PKG's mechanism of action, we screened a yeast two-hybrid library for P. falciparum proteins that interact with P. falciparum PKG (PfPKG) and tested peptide libraries to identify its phosphorylation site preferences. Our data suggest that PfPKG has a distinct phosphorylation site and that PfPKG directly phosphorylates parasite RPT1, one of six AAA+ ATPases present in the 19S regulatory particle of the proteasome. PfPKG and RPT1 interact in vitro, and the interacting fragment of RPT1 carries a PfPKG consensus phosphorylation site; a peptide carrying this consensus site competes with the RPT1 fragment for binding to PfPKG and is efficiently phosphorylated by PfPKG. These data suggest that PfPKG's phosphorylation of RPT1 could contribute to its regulation of parasite proteolysis. We demonstrate that proteolysis plays an important role in a biological process known to require Plasmodium PKG: invasion by sporozoites of hepatocytes. A small-molecule inhibitor of proteasomal activity blocks sporozoite invasion in an additive manner when combined with a Plasmodium PKG-specific inhibitor. Mining the previously described parasite PKG-dependent phosphoproteomes using the consensus phosphorylation motif identified additional proteins that are likely to be direct substrates of the enzyme.
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6
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Deligianni E, Silmon de Monerri NC, McMillan PJ, Bertuccini L, Superti F, Manola M, Spanos L, Louis C, Blackman MJ, Tilley L, Siden-Kiamos I. Essential role of Plasmodium perforin-like protein 4 in ookinete midgut passage. PLoS One 2018; 13:e0201651. [PMID: 30102727 PMCID: PMC6089593 DOI: 10.1371/journal.pone.0201651] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [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: 02/13/2018] [Accepted: 07/19/2018] [Indexed: 01/22/2023] Open
Abstract
Pore forming proteins such as those belonging to the membrane attack/perforin (MACPF) family have important functions in many organisms. Of the five MACPF proteins found in Plasmodium parasites, three have functions in cell passage and one in host cell egress. Here we report an analysis of the perforin-like protein 4, PPLP4, in the rodent parasite Plasmodium berghei. We found that the protein is expressed only in the ookinete, the invasive stage of the parasite formed in the mosquito midgut. Transcriptional analysis revealed that expression of the pplp4 gene commences during ookinete development. The protein was detected in retorts and mature ookinetes. Using two antibodies, the protein was found localized in a dotted pattern, and 3-D SIM super-resolution microcopy revealed the protein in the periphery of the cell. Analysis of a C-terminal mCherry fusion of the protein however showed mainly cytoplasmic label. A pplp4 null mutant formed motile ookinetes, but these were unable to invade and traverse the midgut epithelium resulting in severely impaired oocyst formation and no transmission to naïve mice. However, when in vitro cultured ookinetes were injected into the thorax of the mosquito, thus by-passing midgut passage, sporozoites were formed and the mutant parasites were able to infect naïve mice. Taken together, our data show that PPLP4 is required only for ookinete invasion of the mosquito midgut. Thus PPLP4 has a similar role to the previously studied PPLP3 and PPLP5, raising the question why three proteins with MACPF domains are needed for invasion by the ookinete of the mosquito midgut epithelium.
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Affiliation(s)
- Elena Deligianni
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology—Hellas, Heraklion, Greece
- * E-mail:
| | | | - Paul J. McMillan
- Department of Biochemistry and Molecular Biology, The University of Melbourne, Melbourne, VIC, Australia
- ARC Centre of Excellence for Coherent X-ray Science, The University of Melbourne, Melbourne, VIC, Australia
- Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC, Australia
- Biological Optical Microcopy Platform, The University of Melbourne, Melbourne, VIC, Australia
| | - Lucia Bertuccini
- National Centre for Innovative Technologies in Public Health, National Institute of Health, Rome, Italy
| | - Fabiana Superti
- National Centre for Innovative Technologies in Public Health, National Institute of Health, Rome, Italy
| | - Maria Manola
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology—Hellas, Heraklion, Greece
| | - Lefteris Spanos
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology—Hellas, Heraklion, Greece
| | - Christos Louis
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology—Hellas, Heraklion, Greece
| | - Michael J. Blackman
- The Francis Crick Institute, London, United Kingdom
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Leann Tilley
- Department of Biochemistry and Molecular Biology, The University of Melbourne, Melbourne, VIC, Australia
- ARC Centre of Excellence for Coherent X-ray Science, The University of Melbourne, Melbourne, VIC, Australia
- Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC, Australia
| | - Inga Siden-Kiamos
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology—Hellas, Heraklion, Greece
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7
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Douglas RG, Nandekar P, Aktories JE, Kumar H, Weber R, Sattler JM, Singer M, Lepper S, Sadiq SK, Wade RC, Frischknecht F. Inter-subunit interactions drive divergent dynamics in mammalian and Plasmodium actin filaments. PLoS Biol 2018; 16:e2005345. [PMID: 30011270 PMCID: PMC6055528 DOI: 10.1371/journal.pbio.2005345] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [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: 01/11/2018] [Accepted: 06/13/2018] [Indexed: 01/01/2023] Open
Abstract
Cell motility is essential for protozoan and metazoan organisms and typically relies on the dynamic turnover of actin filaments. In metazoans, monomeric actin polymerises into usually long and stable filaments, while some protozoans form only short and highly dynamic actin filaments. These different dynamics are partly due to the different sets of actin regulatory proteins and partly due to the sequence of actin itself. Here we probe the interactions of actin subunits within divergent actin filaments using a comparative dynamic molecular model and explore their functions using Plasmodium, the protozoan causing malaria, and mouse melanoma derived B16-F1 cells as model systems. Parasite actin tagged to a fluorescent protein (FP) did not incorporate into mammalian actin filaments, and rabbit actin-FP did not incorporate into parasite actin filaments. However, exchanging the most divergent region of actin subdomain 3 allowed such reciprocal incorporation. The exchange of a single amino acid residue in subdomain 2 (N41H) of Plasmodium actin markedly improved incorporation into mammalian filaments. In the parasite, modification of most subunit–subunit interaction sites was lethal, whereas changes in actin subdomains 1 and 4 reduced efficient parasite motility and hence mosquito organ penetration. The strong penetration defects could be rescued by overexpression of the actin filament regulator coronin. Through these comparative approaches we identified an essential and common contributor, subdomain 3, which drives the differential dynamic behaviour of two highly divergent eukaryotic actins in motile cells. Actin is one of the most abundant and conserved proteins across eukaryotes. Its ability to assemble from individual monomers into dynamic polymers is essential for many cellular functions, including division and motility. In most cells, actin is able to form long and stable filaments. However, an actin of the malaria-causing parasite Plasmodium, while having a very similar monomer structure to actins from other eukaryotes, forms only short and unstable filaments. These short and dynamic filaments are crucial in allowing the parasite to move very rapidly in tissue. Here we investigated the basis of these differences. We used molecular dynamics simulations of actin filaments to investigate the actin–actin interfaces in filaments from Plasmodium and rabbit. We next engineered parasites to express chimeric actins that contained different parts of rabbit and parasite actin and thereby identified actin residues important for parasite viability and progression across the life cycle. We could rescue the most prominent defect specifically with overexpression of the actin binding protein coronin. This suggests that the more stable actin harms the parasite and that coronin helps in recycling filaments. By screening the effects of actin chimeras in mammalian cells, we also identified regions that allow these different actins to efficiently interact with each other. Taken together, our results improve our understanding of the interactions required for actin to incorporate into filaments across divergent eukaryotes.
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Affiliation(s)
- Ross G. Douglas
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
| | - Prajwal Nandekar
- Molecular and Cellular Modeling, Heidelberg Institute for Theoretical Studies (HITS), Heidelberg, Germany
- Center for Molecular Biology (ZMBH), DKFZ-ZMBH Alliance, Heidelberg, Germany
| | - Julia-Elisabeth Aktories
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
| | - Hirdesh Kumar
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
- Molecular and Cellular Modeling, Heidelberg Institute for Theoretical Studies (HITS), Heidelberg, Germany
| | - Rebekka Weber
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
| | - Julia M. Sattler
- 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
| | - Simone Lepper
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
| | - S. Kashif Sadiq
- Molecular and Cellular Modeling, Heidelberg Institute for Theoretical Studies (HITS), Heidelberg, Germany
| | - Rebecca C. Wade
- Molecular and Cellular Modeling, Heidelberg Institute for Theoretical Studies (HITS), Heidelberg, Germany
- Center for Molecular Biology (ZMBH), DKFZ-ZMBH Alliance, Heidelberg, Germany
- Interdisciplinary Center for Scientific Computing (IWR), Heidelberg, Germany
- * E-mail: (FF); (RCW)
| | - Friedrich Frischknecht
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
- * E-mail: (FF); (RCW)
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8
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Baroni L, Pollo-Oliveira L, Heck AJ, Altelaar AM, Yatsuda AP. Actin from the apicomplexan Neospora caninum (NcACT) has different isoforms in 2D electrophoresis. Parasitology 2019; 146:33-41. [PMID: 29871709 DOI: 10.1017/S0031182018000872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Apicomplexan parasites have unconventional actins that play a central role in important cellular processes such as apicoplast replication, motility of dense granules, endocytic trafficking and force generation for motility and host cell invasion. In this study, we investigated the actin of the apicomplexan Neospora caninum - a parasite associated with infectious abortion and neonatal mortality in livestock. Neospora caninum actin was detected and identified in two bands by one-dimensional (1D) western blot and in nine spots by the 2D technique. The mass spectrometry data indicated that N. caninum has at least nine different actin isoforms, possibly caused by post-translational modifications. In addition, the C4 pan-actin antibody detected specifically actin in N. caninum cellular extract. Extracellular N. caninum tachyzoites were treated with toxins that act on actin, jasplakinolide and cytochalasin D. Both substances altered the peripheric cytoplasmic localization of actin on tachyzoites. Our findings add complexity to the study of the apicomplexan actin in cellular processes, since the multiple functions of this important protein might be regulated by mechanisms involving post-translational modifications.
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9
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Mueller C, Graindorge A, Soldati-Favre D. Functions of myosin motors tailored for parasitism. Curr Opin Microbiol 2017; 40:113-122. [DOI: 10.1016/j.mib.2017.11.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2017] [Revised: 11/02/2017] [Accepted: 11/02/2017] [Indexed: 01/01/2023]
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10
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Curra C, McMillan PJ, Spanos L, Mollard V, Deligianni E, McFadden G, Tilley L, Siden-Kiamos I. Structured illumination microscopy reveals actin I localization in discreet foci in Plasmodium berghei gametocytes. Exp Parasitol 2017; 181:82-87. [PMID: 28803903 DOI: 10.1016/j.exppara.2017.08.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [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: 03/22/2017] [Revised: 06/30/2017] [Accepted: 08/08/2017] [Indexed: 11/26/2022]
Abstract
Actin has important roles in Plasmodium parasites but its exact function in different life stages is not yet fully elucidated. Here we report the localization of ubiquitous actin I in gametocytes of the rodent model parasite P. berghei. Using an antibody specifically recognizing F-actin and deconvolution microscopy we detected actin I in a punctate pattern in gametocytes. 3D-Structured Illumination Microscopy which allows sub-diffraction limit imaging resolved the signal into structures of less than 130 nm length. A portion of actin I was soluble, but the protein was also found complexed in a stabilized form which could only be completely solubilized by treatment with SDS. An additional population of actin was pelleted at 100 000 × g, consistent with F-actin. Our results suggest that actin in this non-motile form of the parasite is present in short filaments cross-linked to other structures in a cytoskeleton.
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Affiliation(s)
- Chiara Curra
- Institute of Molecular Biology and Biotechnology, FORTH, Heraklion, Greece
| | - Paul J McMillan
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, 3051 VIC, Australia; Biological Optical Microscopy Platform, The University of Melbourne, Melbourne, 3051 VIC, Australia
| | - Lefteris Spanos
- Institute of Molecular Biology and Biotechnology, FORTH, Heraklion, Greece
| | - Vanessa Mollard
- School of BioSciences, The University of Melbourne, Melbourne, 3051 VIC, Australia
| | - Elena Deligianni
- Institute of Molecular Biology and Biotechnology, FORTH, Heraklion, Greece
| | - Geoffrey McFadden
- School of BioSciences, The University of Melbourne, Melbourne, 3051 VIC, Australia
| | - Leann Tilley
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, 3051 VIC, Australia
| | - Inga Siden-Kiamos
- Institute of Molecular Biology and Biotechnology, FORTH, Heraklion, Greece.
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11
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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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Sato Y, Hliscs M, Dunst J, Goosmann C, Brinkmann V, Montagna GN, Matuschewski K. Comparative Plasmodium gene overexpression reveals distinct perturbation of sporozoite transmission by profilin. Mol Biol Cell 2016; 27:2234-44. [PMID: 27226484 PMCID: PMC4945141 DOI: 10.1091/mbc.e15-10-0734] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [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: 10/27/2015] [Accepted: 05/16/2016] [Indexed: 12/27/2022] Open
Abstract
The roles of vital genes, such as those of G-actin–binding proteins, in malaria parasites are underexplored. Overexpression of Plasmodium profilin perturbs actin dynamics only in sporozoites. Strict actin regulation is particularly important for malaria transmission. Mapping of phenotypes can be done by comparative Plasmodium gene overexpression. Plasmodium relies on actin-based motility to migrate from the site of infection and invade target cells. Using a substrate-dependent gliding locomotion, sporozoites are able to move at fast speed (1–3 μm/s). This motility relies on a minimal set of actin regulatory proteins and occurs in the absence of detectable filamentous actin (F-actin). Here we report an overexpression strategy to investigate whether perturbations of F-actin steady-state levels affect gliding locomotion and host invasion. We selected two vital Plasmodium berghei G-actin–binding proteins, C-CAP and profilin, in combination with three stage-specific promoters and mapped the phenotypes afforded by overexpression in all three extracellular motile stages. We show that in merozoites and ookinetes, additional expression does not impair life cycle progression. In marked contrast, overexpression of C-CAP and profilin in sporozoites impairs circular gliding motility and salivary gland invasion. The propensity for productive motility correlates with actin accumulation at the parasite tip, as revealed by combinations of an actin-stabilizing drug and transgenic parasites. Strong expression of profilin, but not C-CAP, resulted in complete life cycle arrest. Comparative overexpression is an alternative experimental genetic strategy to study essential genes and reveals effects of regulatory imbalances that are not uncovered from deletion-mutant phenotyping.
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Affiliation(s)
- Yuko Sato
- Parasitology Unit, Max Planck Institute for Infection Biology, 10117 Berlin, Germany Infectious Diseases Interdisciplinary Research Group, Singapore-Massachusetts Institute of Technology Alliance for Research and Technology, 138602 Singapore
| | - Marion Hliscs
- Parasitology Unit, Max Planck Institute for Infection Biology, 10117 Berlin, Germany School of BioSciences, University of Melbourne, Parkville, 3010 Victoria, Australia
| | - Josefine Dunst
- Parasitology Unit, Max Planck Institute for Infection Biology, 10117 Berlin, Germany Institute for Chemistry and Biochemistry, Freie Universität Berlin, 14195 Berlin, Germany
| | - Christian Goosmann
- Imaging Unit, Max Planck Institute for Infection Biology, 10117 Berlin, Germany
| | - Volker Brinkmann
- Imaging Unit, Max Planck Institute for Infection Biology, 10117 Berlin, Germany
| | - Georgina N Montagna
- Parasitology Unit, Max Planck Institute for Infection Biology, 10117 Berlin, Germany Departamento de Microbiologia, Immunologia e Parasitologia, Universidade Federal de São Paulo, 04039-032 São Paulo, Brazil
| | - Kai Matuschewski
- Parasitology Unit, Max Planck Institute for Infection Biology, 10117 Berlin, Germany Institute of Biology, Humboldt University, 10117 Berlin, Germany
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14
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Douglas RG, Amino R, Sinnis P, Frischknecht F. Active migration and passive transport of malaria parasites. Trends Parasitol 2015; 31:357-62. [PMID: 26001482 DOI: 10.1016/j.pt.2015.04.010] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [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: 02/12/2015] [Revised: 04/22/2015] [Accepted: 04/23/2015] [Indexed: 11/16/2022]
Abstract
Malaria parasites undergo a complex life cycle between their hosts and vectors. During this cycle the parasites invade different types of cells, migrate across barriers, and transfer from one host to another. Recent literature hints at a misunderstanding of the difference between active, parasite-driven migration and passive, circulation-driven movement of the parasite or parasite-infected cells in the various bodily fluids of mosquito and mammalian hosts. Because both active migration and passive transport could be targeted in different ways to interfere with the parasite, a distinction between the two ways the parasite uses to get from one location to another is essential. We discuss the two types of motion needed for parasite dissemination and elaborate on how they could be targeted by future vaccines or drugs.
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Affiliation(s)
- Ross G Douglas
- Integrative Parasitology, Center for Infectious Diseases, University of Heidelberg Medical School, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
| | - Rogerio Amino
- Unité de Biologie et Génétique du Paludisme, Département Parasites et Insectes Vecteurs, Institut Pasteur, 25-28 Rue du Dr Roux, 75015 Paris, France
| | - Photini Sinnis
- Johns Hopkins Malaria Research Institute, Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, 615 North Wolfe Street, Baltimore, MD 21205, USA
| | - Freddy Frischknecht
- Integrative Parasitology, Center for Infectious Diseases, University of Heidelberg Medical School, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany.
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15
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Hliscs M, Millet C, Dixon MW, Siden-Kiamos I, McMillan P, Tilley L. Organization and function of an actin cytoskeleton inPlasmodium falciparumgametocytes. Cell Microbiol 2014; 17:207-25. [DOI: 10.1111/cmi.12359] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Revised: 08/16/2014] [Accepted: 08/19/2014] [Indexed: 01/05/2023]
Affiliation(s)
- Marion Hliscs
- Department of Biochemistry and Molecular Biology; Bio21 Molecular Science and Biotechnology Institute; Melbourne Vic. 3010 Australia
- Australian Research Council Centre of Excellence for Coherent X-ray Science; The University of Melbourne; Melbourne Vic. 3010 Australia
- School of Botany; The University of Melbourne; Melbourne Vic. 3010 Australia
| | - Coralie Millet
- Department of Biochemistry and Molecular Biology; Bio21 Molecular Science and Biotechnology Institute; Melbourne Vic. 3010 Australia
- Australian Research Council Centre of Excellence for Coherent X-ray Science; The University of Melbourne; Melbourne Vic. 3010 Australia
| | - Matthew W. Dixon
- Department of Biochemistry and Molecular Biology; Bio21 Molecular Science and Biotechnology Institute; Melbourne Vic. 3010 Australia
- Australian Research Council Centre of Excellence for Coherent X-ray Science; The University of Melbourne; Melbourne Vic. 3010 Australia
| | - Inga Siden-Kiamos
- Institute of Molecular Biology and Biotechnology; Foundation for Research and Technology; Hellas, 700 13 Heraklion Crete Greece
| | - Paul McMillan
- Department of Biochemistry and Molecular Biology; Bio21 Molecular Science and Biotechnology Institute; Melbourne Vic. 3010 Australia
- The Biological Optical Microscopy Platform; The University of Melbourne; Melbourne Vic. 3010 Australia
| | - Leann Tilley
- Department of Biochemistry and Molecular Biology; Bio21 Molecular Science and Biotechnology Institute; Melbourne Vic. 3010 Australia
- Australian Research Council Centre of Excellence for Coherent X-ray Science; The University of Melbourne; Melbourne Vic. 3010 Australia
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Salamun J, Kallio JP, Daher W, Soldati-Favre D, Kursula I. Structure of Toxoplasma gondii coronin, an actin-binding protein that relocalizes to the posterior pole of invasive parasites and contributes to invasion and egress. FASEB J 2014; 28:4729-47. [PMID: 25114175 DOI: 10.1096/fj.14-252569] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Coronins are involved in the regulation of actin dynamics in a multifaceted way, participating in cell migration and vesicular trafficking. Apicomplexan parasites, which exhibit an actin-dependent gliding motility that is essential for traversal through tissues, as well as invasion of and egress from host cells, express only a single coronin, whereas higher eukaryotes possess several isoforms. We set out to characterize the 3-D structure, biochemical function, subcellular localization, and genetic ablation of Toxoplasma gondii coronin (TgCOR), to shed light on its biological role. A combination of X-ray crystallography, small-angle scattering of X-rays, and light scattering revealed the atomic structure of the conserved WD40 domain and the dimeric arrangement of the full-length protein. TgCOR binds to F-actin and increases the rate and extent of actin polymerization. In vivo, TgCOR relocalizes transiently to the posterior pole of motile and invading parasites, independent of actin dynamics, but concomitant to microneme secretory organelle discharge. TgCOR contributes to, but is not essential for, invasion and egress. Taken together, our data point toward a role for TgCOR in stabilizing newly formed, short filaments and F-actin cross-linking, as well as functions linked to endocytosis and recycling of membranes.
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Affiliation(s)
- Julien Salamun
- Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Juha P Kallio
- Centre for Structural Systems Biology, Helmholtz Centre for Infection Research and German Electron Synchrotron (DESY), Hamburg, Germany; and
| | - Wassim Daher
- Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Dominique Soldati-Favre
- Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland;
| | - Inari Kursula
- Centre for Structural Systems Biology, Helmholtz Centre for Infection Research and German Electron Synchrotron (DESY), Hamburg, Germany; and Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
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17
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Kan A, Tan YH, Angrisano F, Hanssen E, Rogers KL, Whitehead L, Mollard VP, Cozijnsen A, Delves MJ, Crawford S, Sinden RE, McFadden GI, Leckie C, Bailey J, Baum J. Quantitative analysis of Plasmodium ookinete motion in three dimensions suggests a critical role for cell shape in the biomechanics of malaria parasite gliding motility. Cell Microbiol 2014; 16:734-50. [PMID: 24612056 PMCID: PMC4286792 DOI: 10.1111/cmi.12283] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [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: 10/04/2013] [Revised: 01/22/2014] [Accepted: 02/13/2014] [Indexed: 11/28/2022]
Abstract
Motility is a fundamental part of cellular life and survival, including for Plasmodium parasites--single-celled protozoan pathogens responsible for human malaria. The motile life cycle forms achieve motility, called gliding, via the activity of an internal actomyosin motor. Although gliding is based on the well-studied system of actin and myosin, its core biomechanics are not completely understood. Currently accepted models suggest it results from a specifically organized cellular motor that produces a rearward directional force. When linked to surface-bound adhesins, this force is passaged to the cell posterior, propelling the parasite forwards. Gliding motility is observed in all three life cycle stages of Plasmodium: sporozoites, merozoites and ookinetes. However, it is only the ookinetes--formed inside the midgut of infected mosquitoes--that display continuous gliding without the necessity of host cell entry. This makes them ideal candidates for invasion-free biomechanical analysis. Here we apply a plate-based imaging approach to study ookinete motion in three-dimensional (3D) space to understand Plasmodium cell motility and how movement facilitates midgut colonization. Using single-cell tracking and numerical analysis of parasite motion in 3D, our analysis demonstrates that ookinetes move with a conserved left-handed helical trajectory. Investigation of cell morphology suggests this trajectory may be based on the ookinete subpellicular cytoskeleton, with complementary whole and subcellular electron microscopy showing that, like their motion paths, ookinetes share a conserved left-handed corkscrew shape and underlying twisted microtubular architecture. Through comparisons of 3D movement between wild-type ookinetes and a cytoskeleton-knockout mutant we demonstrate that perturbation of cell shape changes motion from helical to broadly linear. Therefore, while the precise linkages between cellular architecture and actomyosin motor organization remain unknown, our analysis suggests that the molecular basis of cell shape may, in addition to motor force, be a key adaptive strategy for malaria parasite dissemination and, as such, transmission.
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Affiliation(s)
- Andrey Kan
- Victoria Research Laboratory, National ICT Australia (NICTA), Department of Computing and Information Systems, University of Melbourne, Melbourne, Vic., 3010, Australia
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18
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Lasonder E, Green JL, Camarda G, Talabani H, Holder AA, Langsley G, Alano P. The Plasmodium falciparum schizont phosphoproteome reveals extensive phosphatidylinositol and cAMP-protein kinase A signaling. J Proteome Res 2012; 11:5323-37. [PMID: 23025827 DOI: 10.1021/pr300557m] [Citation(s) in RCA: 115] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The asexual blood stages of Plasmodium falciparum cause the most lethal form of human malaria. During growth within an infected red blood cell, parasite multiplication and formation of invasive merozoites is called schizogony. Here, we present a detailed analysis of the phosphoproteome of P. falciparum schizonts revealing 2541 unique phosphorylation sites, including 871 novel sites. Prominent roles for cAMP-dependent protein kinase A- and phosphatidylinositol-signaling were identified following analysis by functional enrichment, phosphoprotein interaction network clustering and phospho-motif identification tools. We observed that most key enzymes in the inositol pathway are phosphorylated, which strongly suggests additional levels of regulation and crosstalk with other protein kinases that coregulate different biological processes. A distinct pattern of phosphorylation of proteins involved in merozoite egress and red blood cell invasion was noted. The analyses also revealed that cAMP-PKA signaling is implicated in a wide variety of processes including motility. We verified this finding experimentally using an in vitro kinase assay and identified three novel PKA substrates associated with the glideosome motor complex: myosin A, GAP45 and CDPK1. Therefore, in addition to an established role for CDPK1 in the motor complex, this study reveals the coinvolvement of PKA, further implicating cAMP as an important regulator of host cell invasion.
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Affiliation(s)
- Edwin Lasonder
- Centre for Molecular and Biomolecular Informatics, Nijmegen Centre for Molecular Life Sciences, Radboud University Nijmegen Medical Centre, PO Box 9101, 6500 HB Nijmegen, The Netherlands.
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Angrisano F, Tan YH, Sturm A, McFadden GI, Baum J. Malaria parasite colonisation of the mosquito midgut – Placing the Plasmodium ookinete centre stage. Int J Parasitol 2012; 42:519-27. [DOI: 10.1016/j.ijpara.2012.02.004] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2011] [Revised: 02/03/2012] [Accepted: 02/04/2012] [Indexed: 11/28/2022]
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Asada M, Goto Y, Yahata K, Yokoyama N, Kawai S, Inoue N, Kaneko O, Kawazu SI. Gliding motility of Babesia bovis merozoites visualized by time-lapse video microscopy. PLoS One 2012; 7:e35227. [PMID: 22506073 PMCID: PMC3323635 DOI: 10.1371/journal.pone.0035227] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [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: 02/13/2012] [Accepted: 03/12/2012] [Indexed: 11/22/2022] Open
Abstract
Background Babesia bovis is an apicomplexan intraerythrocytic protozoan parasite that induces babesiosis in cattle after transmission by ticks. During specific stages of the apicomplexan parasite lifecycle, such as the sporozoites of Plasmodium falciparum and tachyzoites of Toxoplasma gondii, host cells are targeted for invasion using a unique, active process termed “gliding motility”. However, it is not thoroughly understood how the merozoites of B. bovis target and invade host red blood cells (RBCs), and gliding motility has so far not been observed in the parasite. Methodology/Principal Findings Gliding motility of B. bovis merozoites was revealed by time-lapse video microscopy. The recorded images revealed that the process included egress of the merozoites from the infected RBC, gliding motility, and subsequent invasion into new RBCs. The gliding motility of B. bovis merozoites was similar to the helical gliding of Toxoplasma tachyzoites. The trails left by the merozoites were detected by indirect immunofluorescence assay using antiserum against B. bovis merozoite surface antigen 1. Inhibition of gliding motility by actin filament polymerization or depolymerization indicated that the gliding motility was driven by actomyosin dependent process. In addition, we revealed the timing of breakdown of the parasitophorous vacuole. Time-lapse image analysis of membrane-stained bovine RBCs showed formation and breakdown of the parasitophorous vacuole within ten minutes of invasion. Conclusions/Significance This is the first report of the gliding motility of B. bovis. Since merozoites of Plasmodium parasites do not glide on a substrate, the gliding motility of B. bovis merozoites is a notable finding.
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Affiliation(s)
- Masahito Asada
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada, Obihiro, Japan
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Angrisano F, Riglar DT, Sturm A, Volz JC, Delves MJ, Zuccala ES, Turnbull L, Dekiwadia C, Olshina MA, Marapana DS, Wong W, Mollard V, Bradin CH, Tonkin CJ, Gunning PW, Ralph SA, Whitchurch CB, Sinden RE, Cowman AF, McFadden GI, Baum J. Spatial localisation of actin filaments across developmental stages of the malaria parasite. PLoS One 2012; 7:e32188. [PMID: 22389687 PMCID: PMC3289632 DOI: 10.1371/journal.pone.0032188] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [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: 11/17/2011] [Accepted: 01/23/2012] [Indexed: 02/02/2023] Open
Abstract
Actin dynamics have been implicated in a variety of developmental processes during the malaria parasite lifecycle. Parasite motility, in particular, is thought to critically depend on an actomyosin motor located in the outer pellicle of the parasite cell. Efforts to understand the diverse roles actin plays have, however, been hampered by an inability to detect microfilaments under native conditions. To visualise the spatial dynamics of actin we generated a parasite-specific actin antibody that shows preferential recognition of filamentous actin and applied this tool to different lifecycle stages (merozoites, sporozoites and ookinetes) of the human and mouse malaria parasite species Plasmodium falciparum and P. berghei along with tachyzoites from the related apicomplexan parasite Toxoplasma gondii. Actin filament distribution was found associated with three core compartments: the nuclear periphery, pellicular membranes of motile or invasive parasite forms and in a ring-like distribution at the tight junction during merozoite invasion of erythrocytes in both human and mouse malaria parasites. Localisation at the nuclear periphery is consistent with an emerging role of actin in facilitating parasite gene regulation. During invasion, we show that the actin ring at the parasite-host cell tight junction is dependent on dynamic filament turnover. Super-resolution imaging places this ring posterior to, and not concentric with, the junction marker rhoptry neck protein 4. This implies motor force relies on the engagement of dynamic microfilaments at zones of traction, though not necessarily directly through receptor-ligand interactions at sites of adhesion during invasion. Combined, these observations extend current understanding of the diverse roles actin plays in malaria parasite development and apicomplexan cell motility, in particular refining understanding on the linkage of the internal parasite gliding motor with the extra-cellular milieu.
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Affiliation(s)
- Fiona Angrisano
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Victoria, Australia
| | - David T. Riglar
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Victoria, Australia
| | - Angelika Sturm
- School of Botany University of Melbourne, Parkville, Victoria, Australia
| | - Jennifer C. Volz
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Victoria, Australia
| | - Michael J. Delves
- Department of Biological Sciences, Imperial College of Science, Technology and Medicine, London, United Kingdom
| | - Elizabeth S. Zuccala
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Victoria, Australia
| | - Lynne Turnbull
- The ithree Institute, University of Technology Sydney, Sydney, New South Wales, Australia
| | - Chaitali Dekiwadia
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, Victoria, Australia
| | - Maya A. Olshina
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Victoria, Australia
| | - Danushka S. Marapana
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
| | - Wilson Wong
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
| | - Vanessa Mollard
- Department of Biological Sciences, Imperial College of Science, Technology and Medicine, London, United Kingdom
| | - Clare H. Bradin
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
| | - Christopher J. Tonkin
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Victoria, Australia
| | - Peter W. Gunning
- Department of Pharmacology, School of Medical Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - Stuart A. Ralph
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, Victoria, Australia
| | - Cynthia B. Whitchurch
- The ithree Institute, University of Technology Sydney, Sydney, New South Wales, Australia
| | - Robert E. Sinden
- School of Botany University of Melbourne, Parkville, Victoria, Australia
| | - Alan F. Cowman
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Victoria, Australia
| | - Geoffrey I. McFadden
- Department of Biological Sciences, Imperial College of Science, Technology and Medicine, London, United Kingdom
| | - Jake Baum
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Victoria, Australia
- * E-mail:
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22
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Angrisano F, Delves MJ, Sturm A, Mollard V, McFadden GI, Sinden RE, Baum J. A GFP-actin reporter line to explore microfilament dynamics across the malaria parasite lifecycle. Mol Biochem Parasitol 2011; 182:93-6. [PMID: 22138565 DOI: 10.1016/j.molbiopara.2011.11.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2011] [Revised: 11/07/2011] [Accepted: 11/15/2011] [Indexed: 11/18/2022]
Abstract
Malaria parasite motility relies on an internal parasite actomyosin motor that, when linked to the host cell substrate, propels motile zoites forward. Despite their key role in this process, attempts to visualize actin microfilaments (F-actin) during motility and under native microscopy conditions have not to date been successful. Towards facilitating their visualization we present here a Plasmodium berghei transgenic line in which a green fluorescent protein (GFP)-actin fusion is constitutively expressed through the lifecycle. Focused investigation of the largest motile form, the insect stage ookinete, demonstrates a large cytosolic pool of actin with no obvious F-actin structures. However, following treatment with the actin filament-stabilizing drug Jasplakinolide, we show evidence for concentration of F-actin dynamics in the parasite pellicle and at polar apices. These observations support current models for gliding motility and establish a cellular tool for further exploration of the diverse roles actin is thought to play throughout parasite development.
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Affiliation(s)
- Fiona Angrisano
- Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, 3052, Australia
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Siden-Kiamos I, Louis C, Matuschewski K. Evidence for filamentous actin in ookinetes of a malarial parasite. Mol Biochem Parasitol 2011; 181:186-9. [PMID: 22101204 DOI: 10.1016/j.molbiopara.2011.11.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2011] [Revised: 10/13/2011] [Accepted: 11/02/2011] [Indexed: 11/26/2022]
Abstract
Extracellular stages of apicomplexan parasites utilize their own actin myosin motor machinery for gliding locomotion, penetration of cell barriers, and host cell invasion. Thus far, filamentous actin could not be visualized by standard microscopic techniques in vivo. Here, we describe the generation of a novel peptide antibody against the divergent amino-terminal portion of the major Plasmodium isoform, actin I. We show that our antiserum, termed Ab-actinI-I, is conformation-specific. In motile ookinetes it recognizes actin in rod-like structures, which are sensitive to inhibitors interfering with actin polymerization. The average size of the rods is 600 nm, which is considerably longer than what has been detected in in vitro studies of actin filaments.
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Affiliation(s)
- Inga Siden-Kiamos
- Institute of Molecular Biology and Biotechnology, FORTH, N. Plastira 100, Vassilika Vouton, Heraklion 700 13, Crete, Greece.
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Skillman KM, Diraviyam K, Khan A, Tang K, Sept D, Sibley LD. Evolutionarily divergent, unstable filamentous actin is essential for gliding motility in apicomplexan parasites. PLoS Pathog 2011; 7:e1002280. [PMID: 21998582 DOI: 10.1371/journal.ppat.1002280] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2011] [Accepted: 08/17/2011] [Indexed: 01/05/2023] Open
Abstract
Apicomplexan parasites rely on a novel form of actin-based motility called gliding, which depends on parasite actin polymerization, to migrate through their hosts and invade cells. However, parasite actins are divergent both in sequence and function and only form short, unstable filaments in contrast to the stability of conventional actin filaments. The molecular basis for parasite actin filament instability and its relationship to gliding motility remain unresolved. We demonstrate that recombinant Toxoplasma (TgACTI) and Plasmodium (PfACTI and PfACTII) actins polymerized into very short filaments in vitro but were induced to form long, stable filaments by addition of equimolar levels of phalloidin. Parasite actins contain a conserved phalloidin-binding site as determined by molecular modeling and computational docking, yet vary in several residues that are predicted to impact filament stability. In particular, two residues were identified that form intermolecular contacts between different protomers in conventional actin filaments and these residues showed non-conservative differences in apicomplexan parasites. Substitution of divergent residues found in TgACTI with those from mammalian actin resulted in formation of longer, more stable filaments in vitro. Expression of these stabilized actins in T. gondii increased sensitivity to the actin-stabilizing compound jasplakinolide and disrupted normal gliding motility in the absence of treatment. These results identify the molecular basis for short, dynamic filaments in apicomplexan parasites and demonstrate that inherent instability of parasite actin filaments is a critical adaptation for gliding motility.
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Siden-Kiamos I, Ganter M, Kunze A, Hliscs M, Steinbüchel M, Mendoza J, Sinden RE, Louis C, Matuschewski K. Stage-specific depletion of myosin A supports an essential role in motility of malarial ookinetes. Cell Microbiol 2011; 13:1996-2006. [PMID: 21899701 DOI: 10.1111/j.1462-5822.2011.01686.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Functional analysis of Plasmodium genes by classical reverse genetics is currently limited to mutants that are viable during erythrocytic schizogony, the pathogenic phase of the malaria parasite where transfection is performed. Here, we describe a conceptually simple experimental approach to study the function of genes essential to the asexual blood stages in a subsequent life cycle stage by a promoter-swap approach. As a proof of concept we targeted the unconventional class XIV myosin MyoA, which is known to be required for Toxoplasma gondii tachyzoite locomotion and host cell invasion. By placing the corresponding Plasmodium berghei gene, PbMyoA, under the control of the apical membrane antigen 1 (AMA1) promoter, expression in blood stages is maintained but switched off during transmission to the insect vector, i.e. ookinetes. In those mutant ookinetes gliding motility is entirely abolished resulting in a complete block of life cycle progression in Anopheles mosquitoes. Similar approaches should permit the analysis of gene function in the mosquito forms that are shared with the erythrocytic stages of the malaria parasite.
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Affiliation(s)
- Inga Siden-Kiamos
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, 71110 Heraklion, Crete, Greece
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Deligianni E, Morgan RN, Bertuccini L, Kooij TWA, Laforge A, Nahar C, Poulakakis N, Schüler H, Louis C, Matuschewski K, Siden-Kiamos I. Critical role for a stage-specific actin in male exflagellation of the malaria parasite. Cell Microbiol 2011; 13:1714-30. [DOI: 10.1111/j.1462-5822.2011.01652.x] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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Siden-Kiamos I, Schüler H, Liakopoulos D, Louis C. Arp1, an actin-related protein, in Plasmodium berghei. Mol Biochem Parasitol 2010; 173:88-96. [DOI: 10.1016/j.molbiopara.2010.05.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2009] [Revised: 04/23/2010] [Accepted: 05/10/2010] [Indexed: 10/19/2022]
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Doi Y, Shinzawa N, Fukumoto S, Okano H, Kanuka H. ADF2 is required for transformation of the ookinete and sporozoite in malaria parasite development. Biochem Biophys Res Commun 2010; 397:668-72. [DOI: 10.1016/j.bbrc.2010.05.155] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2010] [Accepted: 05/27/2010] [Indexed: 01/07/2023]
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Affiliation(s)
- Ryan C Smith
- Department of Molecular Microbiology and Immunology, Malaria Research Institute, The Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
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Frénal K, Soldati-Favre D. Role of the parasite and host cytoskeleton in apicomplexa parasitism. Cell Host Microbe 2009; 5:602-11. [PMID: 19527887 DOI: 10.1016/j.chom.2009.05.013] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2009] [Revised: 05/22/2009] [Accepted: 05/28/2009] [Indexed: 11/25/2022]
Abstract
The phylum Apicomplexa includes a large and diverse group of obligate intracellular parasites that rely on actomyosin-based motility to migrate, enter host cells, and egress from infected cells. To ensure their intracellular survival and replication, the apicomplexans have evolved sophisticated strategies for subversion of the host cytoskeleton. Given the properties in common between the host and parasite cytoskeleton, dissecting their individual contribution to the establishment of parasitic infection has been challenging. Nevertheless, recent studies have provided new insights into the mechanisms by which parasites subvert the dynamic properties of host actin and tubulin to promote their entry, development, and egress.
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Affiliation(s)
- Karine Frénal
- Department of Microbiology and Molecular Medicine, CMU, University of Geneva, 1 rue Michel-Servet, 1211 Geneva 4, Switzerland.
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Lal K, Prieto JH, Bromley E, Sanderson SJ, Yates JR, Wastling JM, Tomley FM, Sinden RE. Characterisation of Plasmodium invasive organelles; an ookinete microneme proteome. Proteomics 2009; 9:1142-51. [PMID: 19206106 DOI: 10.1002/pmic.200800404] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Secretion of microneme proteins is essential to Plasmodium invasion but the molecular composition of these secretory organelles remains poorly defined. Here, we describe the first Plasmodium microneme proteome. Purification of micronemes by subcellular fractionation from cultured ookinetes was confirmed by enrichment of known micronemal proteins and electron microscopy. Quantitation of electron micrographs showed >14-fold microneme enrichment compared to the intact ookinete, such that micronemes comprised 85% of the identifiable organelles in the fraction. Gel LC-MS/MS of the most abundant protein constituents of the fraction identified three known micronemal proteins chitinase, CTRP, SOAP, together with protein disulphide isomerase (PDI) and HSP70. Highly sensitive MudPIT shotgun proteomics described a total of 345 proteins in the fraction. M1 aminopeptidase and PDI, the former a recognised target of drug development, were both shown to have a micronemal location by IFA. We further identified numerous proteins with established vesicle trafficking and signaling functions consistent with micronemes being part of a regulated secretory pathway. Previously uncharacterised proteins comprise the largest functional group of the microneme proteome and will include secreted proteins important to invasion.
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Affiliation(s)
- Kalpana Lal
- Division of Cell and Molecular Biology, Imperial College London, UK.
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Abstract
Ookinetes are the motile and invasive stages of Plasmodium parasites in the mosquito host. Here we explore the role of intracellular Ca2+ in ookinete survival and motility as well as in the formation of oocysts in vitro in the rodent malaria parasite Plasmodium berghei. Treatment with the Ca2+ ionophore A23187 induced death of the parasite, an effect that could be prevented if the ookinetes were co-incubated with insect cells before incubation with the ionophore. Treatment with the intracellular calcium chelator BAPTA/AM resulted in increased formation of oocysts in vitro. Calcium imaging in the ookinete using fluorescent calcium indicators revealed that the purified ookinetes have an intracellular calcium concentration in the range of 100 nm. Intracellular calcium levels decreased substantially when the ookinetes were incubated with insect cells and their motility was concomitantly increased. Our results suggest a pleiotropic role for intracellular calcium in the ookinete.
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Abstract
This study presents the first characterization of a WD40 repeat-containing myosin identified in the apicomplexan parasite Gregarina polymorpha. This 222.7 kDa myosin, GpMyoF, contains a canonical myosin motor domain, a neck domain with 6 IQ motifs, a tail domain containing short regions of predicted coiled-coil structure, and, most notably, multiple WD40 repeats at the C-terminus. In other proteins such repeats assemble into a beta-propeller structure implicated in mediating protein-protein interactions. Confocal microscopy suggests that GpMyoF is localized to the annular myonemes that gird the parasite cortex. Extraction studies indicate that this myosin shows an unusually tight association with the cytoskeletal fraction and can be solubilized only by treatment with high pH (11.5) or the anionic detergent sarkosyl. This novel myosin and its homologs, which have been identified in several related genera, appear to be unique to the Apicomplexa and represent the only myosins known to contain the WD40 domain. The function of this myosin in G. polymorpha or any of the other apicomplexan parasites remains uncertain.
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Affiliation(s)
- Matthew B Heintzelman
- Department of Biology, Program in Cell Biology and Biochemistry, Bucknell University, Lewisburg, Pennsylvania 17837, USA.
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