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Morano AA, Rudlaff RM, Dvorin JD. A PPP-type pseudophosphatase is required for the maintenance of basal complex integrity in Plasmodium falciparum. Nat Commun 2023; 14:3916. [PMID: 37400439 DOI: 10.1038/s41467-023-39435-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Accepted: 06/13/2023] [Indexed: 07/05/2023] Open
Abstract
During its asexual blood stage, P. falciparum replicates via schizogony, wherein dozens of daughter cells are formed within a single parent. The basal complex, a contractile ring that separates daughter cells, is critical for schizogony. In this study, we identify a Plasmodium basal complex protein essential for basal complex maintenance. Using multiple microscopy techniques, we demonstrate that PfPPP8 is required for uniform basal complex expansion and maintenance of its integrity. We characterize PfPPP8 as the founding member of a novel family of pseudophosphatases with homologs in other Apicomplexan parasites. By co-immunoprecipitation, we identify two additional new basal complex proteins. We characterize the unique temporal localizations of these new basal complex proteins (late-arriving) and of PfPPP8 (early-departing). In this work, we identify a novel basal complex protein, determine its specific role in segmentation, identify a new pseudophosphatase family, and establish that the P. falciparum basal complex is a dynamic structure.
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Affiliation(s)
- Alexander A Morano
- Biological and Biomedical Sciences, Harvard Medical School, Boston, MA, 02115, USA
- Division of Infectious Diseases, Boston Children's Hospital, Boston, MA, 02115, USA
| | - Rachel M Rudlaff
- Biological and Biomedical Sciences, Harvard Medical School, Boston, MA, 02115, USA
- Division of Infectious Diseases, Boston Children's Hospital, Boston, MA, 02115, USA
| | - Jeffrey D Dvorin
- Division of Infectious Diseases, Boston Children's Hospital, Boston, MA, 02115, USA.
- Department of Pediatrics, Harvard Medical School, Boston, MA, 02115, USA.
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2
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Xu Z, Gu Y, Chen J, Chen X, Song Y, Fan J, Ji X, Li Y, Zhang W, Zhang R. Epigenome-wide gene–age interaction study reveals reversed effects of MORN1 DNA methylation on survival between young and elderly oral squamous cell carcinoma patients. Front Oncol 2022; 12:941731. [PMID: 35965572 PMCID: PMC9366171 DOI: 10.3389/fonc.2022.941731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Accepted: 06/28/2022] [Indexed: 12/04/2022] Open
Abstract
DNA methylation serves as a reversible and prognostic biomarker for oral squamous cell carcinoma (OSCC) patients. It is unclear whether the effect of DNA methylation on OSCC overall survival varies with age. As a result, we performed a two-phase gene–age interaction study of OSCC prognosis on an epigenome-wide scale using the Cox proportional hazards model. We identified one CpG probe, cg11676291MORN1, whose effect was significantly modified by age (HRdiscovery = 1.018, p = 4.07 × 10−07, FDR-q = 3.67 × 10−02; HRvalidation = 1.058, p = 8.09 × 10−03; HRcombined = 1.019, p = 7.36 × 10−10). Moreover, there was an antagonistic interaction between hypomethylation of cg11676291MORN1 and age (HRinteraction = 0.284; 95% CI, 0.135–0.597; p = 9.04 × 10−04). The prognosis of OSCC patients was well discriminated by the prognostic score incorporating cg11676291MORN1–age interaction (HRhigh vs. low = 3.66, 95% CI: 2.40–5.60, p = 1.93 × 10−09). By adding 24 significant gene–age interactions using a looser criterion, we significantly improved the area under the receiver operating characteristic curve (AUC) of the model at 3- and 5-year prognostic prediction (AUC3-year = 0.80, AUC5-year = 0.79, C-index = 0.75). Our study identified a significant interaction between cg11676291MORN1 and age on OSCC survival, providing a potential therapeutic target for OSCC patients.
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Affiliation(s)
- Ziang Xu
- Jiangsu Key Laboratory of Oral Diseases, Nanjing Medical University, Nanjing, China
- Department of Oral Special Consultation, Affiliated Stomatological Hospital of Nanjing Medical University, Nanjing, China
| | - Yan Gu
- Jiangsu Key Laboratory of Oral Diseases, Nanjing Medical University, Nanjing, China
- Department of Orthodontics, Affiliated Stomatological Hospital of Nanjing Medical University, Nanjing, China
- Jiangsu Province Engineering Research Center of Stomatological Translational Medicine, Nanjing Medical University, Nanjing, China
| | - Jiajin Chen
- Department of Biostatistics, Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, China
| | - Xinlei Chen
- Jiangsu Key Laboratory of Oral Diseases, Nanjing Medical University, Nanjing, China
- Department of Oral Special Consultation, Affiliated Stomatological Hospital of Nanjing Medical University, Nanjing, China
| | - Yunjie Song
- Department of Biostatistics, Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, China
| | - Juanjuan Fan
- Department of Biostatistics, Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, China
| | - Xinyu Ji
- Department of Biostatistics, Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, China
| | - Yanyan Li
- Jiangsu Key Laboratory of Oral Diseases, Nanjing Medical University, Nanjing, China
- Department of Oral Special Consultation, Affiliated Stomatological Hospital of Nanjing Medical University, Nanjing, China
| | - Wei Zhang
- Jiangsu Key Laboratory of Oral Diseases, Nanjing Medical University, Nanjing, China
- Department of Oral Special Consultation, Affiliated Stomatological Hospital of Nanjing Medical University, Nanjing, China
- *Correspondence: Ruyang Zhang, ; Wei Zhang,
| | - Ruyang Zhang
- Department of Biostatistics, Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, China
- China International Cooperation Center for Environment and Human Health, Nanjing Medical University, Nanjing, China
- *Correspondence: Ruyang Zhang, ; Wei Zhang,
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3
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Qian P, Wang X, Zhong CQ, Wang J, Cai M, Nguitragool W, Li J, Cui H, Yuan J. Inner membrane complex proteomics reveals a palmitoylation regulation critical for intraerythrocytic development of malaria parasite. eLife 2022; 11:77447. [PMID: 35775739 PMCID: PMC9293000 DOI: 10.7554/elife.77447] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Accepted: 06/24/2022] [Indexed: 11/21/2022] Open
Abstract
Malaria is caused by infection of the erythrocytes by the parasites Plasmodium. Inside the erythrocytes, the parasites multiply via schizogony, an unconventional cell division mode. The inner membrane complex (IMC), an organelle located beneath the parasite plasma membrane, serving as the platform for protein anchorage, is essential for schizogony. So far, the complete repertoire of IMC proteins and their localization determinants remain unclear. Here we used biotin ligase (TurboID)-based proximity labeling to compile the proteome of the schizont IMC of the rodent malaria parasite Plasmodium yoelii. In total, 300 TurboID-interacting proteins were identified. 18 of 21 selected candidates were confirmed to localize in the IMC, indicating good reliability. In light of the existing palmitome of Plasmodium falciparum, 83 proteins of the P. yoelii IMC proteome are potentially palmitoylated. We further identified DHHC2 as the major resident palmitoyl-acyl-transferase of the IMC. Depletion of DHHC2 led to defective schizont segmentation and growth arrest both in vitro and in vivo. DHHC2 was found to palmitoylate two critical IMC proteins CDPK1 and GAP45 for their IMC localization. In summary, this study reports an inventory of new IMC proteins and demonstrates a central role of DHHC2 in governing the IMC localization of proteins during the schizont development.
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Affiliation(s)
- Pengge Qian
- Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, China
| | - Xu Wang
- Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, China
| | - Chuan-Qi Zhong
- Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, China
| | - Jiaxu Wang
- Xiamen Center for Disease Control and Prevention, Xiamen, China
| | - Mengya Cai
- Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, China
| | - Wang Nguitragool
- Department of Molecular Tropical Medicine and Genetics, Mahidol University, Bangkok, Thailand
| | - Jian Li
- Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, China
| | - Huiting Cui
- Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, China
| | - Jing Yuan
- Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, China
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4
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Abstract
Plasmodium falciparum, the Apicomplexan parasite that causes the most severe form of human malaria, divides via schizogony during the asexual blood stage of its life cycle. In this method of cell division, multiple daughter cells are generated from a single schizont by segmentation. During segmentation, the basal complex forms at the basal end of the nascent daughter parasites and likely facilitates cell shape and cytokinesis. The requirement and function for each of the individual protein components within the basal complex remain largely unknown in P. falciparum. In this work, we demonstrate that the P. falciparum membrane occupation and recognition nexus repeat-containing protein 1 (PfMORN1) is not required for asexual replication. Following inducible knockout of PfMORN1, we find no detectable defect in asexual parasite morphology or replicative fitness. IMPORTANCEPlasmodium falciparum parasites cause the most severe form of human malaria. During the clinically relevant blood stage of its life cycle, the parasites divide via schizogony. In this divergent method of cell division, the components for multiple daughter cells are generated within a common cytoplasm. At the end of schizogony, segmentation partitions the organelles into invasive daughter parasites. The basal complex is a ring-shaped molecular machine that is critical for segmentation. The requirement for individual proteins within the basal complex is incompletely understood. We demonstrate that the PfMORN1 protein is dispensable for blood stage replication of P. falciparum. This result highlights important differences between Plasmodium parasites and Toxoplasma gondii, where the ortholog T. gondii MORN1 (TgMORN1) is required for asexual replication.
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5
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Wiser MF. Unique Endomembrane Systems and Virulence in Pathogenic Protozoa. Life (Basel) 2021; 11:life11080822. [PMID: 34440567 PMCID: PMC8401336 DOI: 10.3390/life11080822] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 08/10/2021] [Accepted: 08/10/2021] [Indexed: 02/06/2023] Open
Abstract
Virulence in pathogenic protozoa is often tied to secretory processes such as the expression of adhesins on parasite surfaces or the secretion of proteases to assisted in tissue invasion and other proteins to avoid the immune system. This review is a broad overview of the endomembrane systems of pathogenic protozoa with a focus on Giardia, Trichomonas, Entamoeba, kinetoplastids, and apicomplexans. The focus is on unique features of these protozoa and how these features relate to virulence. In general, the basic elements of the endocytic and exocytic pathways are present in all protozoa. Some of these elements, especially the endosomal compartments, have been repurposed by the various species and quite often the repurposing is associated with virulence. The Apicomplexa exhibit the most unique endomembrane systems. This includes unique secretory organelles that play a central role in interactions between parasite and host and are involved in the invasion of host cells. Furthermore, as intracellular parasites, the apicomplexans extensively modify their host cells through the secretion of proteins and other material into the host cell. This includes a unique targeting motif for proteins destined for the host cell. Most notable among the apicomplexans is the malaria parasite, which extensively modifies and exports numerous proteins into the host erythrocyte. These modifications of the host erythrocyte include the formation of unique membranes and structures in the host erythrocyte cytoplasm and on the erythrocyte membrane. The transport of parasite proteins to the host erythrocyte involves several unique mechanisms and components, as well as the generation of compartments within the erythrocyte that participate in extraparasite trafficking.
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Affiliation(s)
- Mark F Wiser
- Department of Tropical Medicine, Tulane University School of Public Health and Tropical Medicine, New Orleans, LA 70112, USA
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6
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Wichers JS, Wunderlich J, Heincke D, Pazicky S, Strauss J, Schmitt M, Kimmel J, Wilcke L, Scharf S, von Thien H, Burda PC, Spielmann T, Löw C, Filarsky M, Bachmann A, Gilberger TW. Identification of novel inner membrane complex and apical annuli proteins of the malaria parasite Plasmodium falciparum. Cell Microbiol 2021; 23:e13341. [PMID: 33830607 DOI: 10.1111/cmi.13341] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 03/29/2021] [Accepted: 04/05/2021] [Indexed: 02/06/2023]
Abstract
The inner membrane complex (IMC) is a defining feature of apicomplexan parasites, which confers stability and shape to the cell, functions as a scaffolding compartment during the formation of daughter cells and plays an important role in motility and invasion during different life cycle stages of these single-celled organisms. To explore the IMC proteome of the malaria parasite Plasmodium falciparum we applied a proximity-dependent biotin identification (BioID)-based proteomics approach, using the established IMC marker protein Photosensitized INA-Labelled protein 1 (PhIL1) as bait in asexual blood-stage parasites. Subsequent mass spectrometry-based peptide identification revealed enrichment of 12 known IMC proteins and several uncharacterized candidate proteins. We validated nine of these previously uncharacterized proteins by endogenous GFP-tagging. Six of these represent new IMC proteins, while three proteins have a distinct apical localization that most likely represents structures described as apical annuli in Toxoplasma gondii. Additionally, various Kelch13 interacting candidates were identified, suggesting an association of the Kelch13 compartment and the IMC in schizont and merozoite stages. This work extends the number of validated IMC proteins in the malaria parasite and reveals for the first time the existence of apical annuli proteins in P. falciparum. Additionally, it provides evidence for a spatial association between the Kelch13 compartment and the IMC in late blood-stage parasites.
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Affiliation(s)
- Jan Stephan Wichers
- Centre for Structural Systems Biology, Hamburg, Germany.,Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany.,University of Hamburg, Hamburg, Germany
| | - Juliane Wunderlich
- Centre for Structural Systems Biology, Hamburg, Germany.,European Molecular Biology Laboratory, Hamburg Unit, Hamburg, Germany
| | - Dorothee Heincke
- Centre for Structural Systems Biology, Hamburg, Germany.,Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany.,University of Hamburg, Hamburg, Germany
| | - Samuel Pazicky
- Centre for Structural Systems Biology, Hamburg, Germany.,European Molecular Biology Laboratory, Hamburg Unit, Hamburg, Germany
| | - Jan Strauss
- Centre for Structural Systems Biology, Hamburg, Germany.,Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany.,University of Hamburg, Hamburg, Germany
| | - Marius Schmitt
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - Jessica Kimmel
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - Louisa Wilcke
- Centre for Structural Systems Biology, Hamburg, Germany.,Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany.,University of Hamburg, Hamburg, Germany
| | - Sarah Scharf
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - Heidrun von Thien
- Centre for Structural Systems Biology, Hamburg, Germany.,Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany.,University of Hamburg, Hamburg, Germany
| | - Paul-Christian Burda
- Centre for Structural Systems Biology, Hamburg, Germany.,Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany.,University of Hamburg, Hamburg, Germany
| | - Tobias Spielmann
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - Christian Löw
- Centre for Structural Systems Biology, Hamburg, Germany.,European Molecular Biology Laboratory, Hamburg Unit, Hamburg, Germany
| | - Michael Filarsky
- Centre for Structural Systems Biology, Hamburg, Germany.,University of Hamburg, Hamburg, Germany
| | - Anna Bachmann
- Centre for Structural Systems Biology, Hamburg, Germany.,Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany.,University of Hamburg, Hamburg, Germany.,German Centre for Infection Research (DZIF), partner site Hamburg-Borstel-Lübeck-Riems, Braunschweig, Germany
| | - Tim W Gilberger
- Centre for Structural Systems Biology, Hamburg, Germany.,Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany.,University of Hamburg, Hamburg, Germany
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7
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Singer M, Frischknecht F. Fluorescent tagging of Plasmodium circumsporozoite protein allows imaging of sporozoite formation but blocks egress from oocysts. Cell Microbiol 2021; 23:e13321. [PMID: 33600048 DOI: 10.1111/cmi.13321] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 02/10/2021] [Accepted: 02/16/2021] [Indexed: 01/23/2023]
Abstract
The circumsporozoite protein, CSP, is the major surface protein of Plasmodium sporozoites, the form of malaria parasites transmitted by mosquitoes. CSP is involved in sporozoite formation within and egress from oocysts, entry into mosquito salivary glands and mammalian liver as well as migration in the skin. Yet, how CSP facilitates sporozoite formation, oocyst egress and hepatocyte specific invasion is still not fully understood. Here, we aimed at generating a series of parasites expressing full-length versions of CSP with internally inserted green fluorescent protein between known domains at the endogenous csp locus. This enabled the investigation of sporozoite formation in living oocysts. GFP insertion after the signal peptide leads to cleavage of GFP before the fusion protein reached the plasma membrane while insertion of GFP before or after the TSR domain prevented sporozoite egress and liver invasion. These data suggest different strategies for obtaining mature salivary gland sporozoites that express GFP-CSP fusions.
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Affiliation(s)
- Mirko Singer
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
- Experimental Parasitology, Department for Veterinary Sciences, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Friedrich Frischknecht
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
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8
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Gubbels MJ, Coppens I, Zarringhalam K, Duraisingh MT, Engelberg K. The Modular Circuitry of Apicomplexan Cell Division Plasticity. Front Cell Infect Microbiol 2021; 11:670049. [PMID: 33912479 PMCID: PMC8072463 DOI: 10.3389/fcimb.2021.670049] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Accepted: 03/22/2021] [Indexed: 12/31/2022] Open
Abstract
The close-knit group of apicomplexan parasites displays a wide variety of cell division modes, which differ between parasites as well as between different life stages within a single parasite species. The beginning and endpoint of the asexual replication cycles is a 'zoite' harboring the defining apical organelles required for host cell invasion. However, the number of zoites produced per division round varies dramatically and can unfold in several different ways. This plasticity of the cell division cycle originates from a combination of hard-wired developmental programs modulated by environmental triggers. Although the environmental triggers and sensors differ between species and developmental stages, widely conserved secondary messengers mediate the signal transduction pathways. These environmental and genetic input integrate in division-mode specific chromosome organization and chromatin modifications that set the stage for each division mode. Cell cycle progression is conveyed by a smorgasbord of positively and negatively acting transcription factors, often acting in concert with epigenetic reader complexes, that can vary dramatically between species as well as division modes. A unique set of cell cycle regulators with spatially distinct localization patterns insert discrete check points which permit individual control and can uncouple general cell cycle progression from nuclear amplification. Clusters of expressed genes are grouped into four functional modules seen in all division modes: 1. mother cytoskeleton disassembly; 2. DNA replication and segregation (D&S); 3. karyokinesis; 4. zoite assembly. A plug-and-play strategy results in the variety of extant division modes. The timing of mother cytoskeleton disassembly is hard-wired at the species level for asexual division modes: it is either the first step, or it is the last step. In the former scenario zoite assembly occurs at the plasma membrane (external budding), and in the latter scenario zoites are assembled in the cytoplasm (internal budding). The number of times each other module is repeated can vary regardless of this first decision, and defines the modes of cell division: schizogony, binary fission, endodyogeny, endopolygeny.
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Affiliation(s)
- Marc-Jan Gubbels
- Department of Biology, Boston College, Chestnut Hill, MA, United States
| | - Isabelle Coppens
- Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, United States
| | - Kourosh Zarringhalam
- Department of Mathematics, University of Massachusetts Boston, Boston, MA, United States
| | - Manoj T. Duraisingh
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, MA, United States
| | - Klemens Engelberg
- Department of Biology, Boston College, Chestnut Hill, MA, United States
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9
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Ferreira JL, Heincke D, Wichers JS, Liffner B, Wilson DW, Gilberger TW. The Dynamic Roles of the Inner Membrane Complex in the Multiple Stages of the Malaria Parasite. Front Cell Infect Microbiol 2021; 10:611801. [PMID: 33489940 PMCID: PMC7820811 DOI: 10.3389/fcimb.2020.611801] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 11/30/2020] [Indexed: 01/31/2023] Open
Abstract
Apicomplexan parasites, such as human malaria parasites, have complex lifecycles encompassing multiple and diverse environmental niches. Invading, replicating, and escaping from different cell types, along with exploiting each intracellular niche, necessitate large and dynamic changes in parasite morphology and cellular architecture. The inner membrane complex (IMC) is a unique structural element that is intricately involved with these distinct morphological changes. The IMC is a double membrane organelle that forms de novo and is located beneath the plasma membrane of these single-celled organisms. In Plasmodium spp. parasites it has three major purposes: it confers stability and shape to the cell, functions as an important scaffolding compartment during the formation of daughter cells, and plays a major role in motility and invasion. Recent years have revealed greater insights into the architecture, protein composition and function of the IMC. Here, we discuss the multiple roles of the IMC in each parasite lifecycle stage as well as insights into its sub-compartmentalization, biogenesis, disassembly and regulation during stage conversion of P. falciparum.
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Affiliation(s)
- Josie Liane Ferreira
- Centre for Structural Systems Biology, Hamburg, Germany
- Heinrich Pette Institut, Leibniz-Institut für Experimentelle Virologie, Hamburg, Germany
| | - Dorothee Heincke
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
- University of Hamburg, Hamburg, Germany
| | - Jan Stephan Wichers
- Centre for Structural Systems Biology, Hamburg, Germany
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
- University of Hamburg, Hamburg, Germany
| | - Benjamin Liffner
- Research Centre for Infectious Diseases, School of Biological Sciences, University of Adelaide, Adelaide, SA, Australia
| | - Danny W. Wilson
- Research Centre for Infectious Diseases, School of Biological Sciences, University of Adelaide, Adelaide, SA, Australia
- Burnet Institute, Melbourne, VIC, Australia
| | - Tim-Wolf Gilberger
- Centre for Structural Systems Biology, Hamburg, Germany
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
- University of Hamburg, Hamburg, Germany
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10
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Three-dimensional ultrastructure of Plasmodium falciparum throughout cytokinesis. PLoS Pathog 2020; 16:e1008587. [PMID: 32511279 PMCID: PMC7302870 DOI: 10.1371/journal.ppat.1008587] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 06/18/2020] [Accepted: 04/30/2020] [Indexed: 12/23/2022] Open
Abstract
New techniques for obtaining electron microscopy data through the cell volume are being increasingly utilized to answer cell biologic questions. Here, we present a three-dimensional atlas of Plasmodium falciparum ultrastructure throughout parasite cell division. Multiple wild type schizonts at different stages of segmentation, or budding, were imaged and rendered, and the 3D structure of their organelles and daughter cells are shown. Our high-resolution volume electron microscopy both confirms previously described features in 3D and adds new layers to our understanding of Plasmodium nuclear division. Interestingly, we demonstrate asynchrony of the final nuclear division, a process that had previously been reported as synchronous. Use of volume electron microscopy techniques for biological imaging is gaining prominence, and there is much we can learn from applying them to answer questions about Plasmodium cell biology. We provide this resource to encourage readers to consider adding these techniques to their cell biology toolbox.
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11
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Gubbels MJ, Keroack CD, Dangoudoubiyam S, Worliczek HL, Paul AS, Bauwens C, Elsworth B, Engelberg K, Howe DK, Coppens I, Duraisingh MT. Fussing About Fission: Defining Variety Among Mainstream and Exotic Apicomplexan Cell Division Modes. Front Cell Infect Microbiol 2020; 10:269. [PMID: 32582569 PMCID: PMC7289922 DOI: 10.3389/fcimb.2020.00269] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2020] [Accepted: 05/06/2020] [Indexed: 12/17/2022] Open
Abstract
Cellular reproduction defines life, yet our textbook-level understanding of cell division is limited to a small number of model organisms centered around humans. The horizon on cell division variants is expanded here by advancing insights on the fascinating cell division modes found in the Apicomplexa, a key group of protozoan parasites. The Apicomplexa display remarkable variation in offspring number, whether karyokinesis follows each S/M-phase or not, and whether daughter cells bud in the cytoplasm or bud from the cortex. We find that the terminology used to describe the various manifestations of asexual apicomplexan cell division emphasizes either the number of offspring or site of budding, which are not directly comparable features and has led to confusion in the literature. Division modes have been primarily studied in two human pathogenic Apicomplexa, malaria-causing Plasmodium spp. and Toxoplasma gondii, a major cause of opportunistic infections. Plasmodium spp. divide asexually by schizogony, producing multiple daughters per division round through a cortical budding process, though at several life-cycle nuclear amplifications stages, are not followed by karyokinesis. T. gondii divides by endodyogeny producing two internally budding daughters per division round. Here we add to this diversity in replication mechanisms by considering the cattle parasite Babesia bigemina and the pig parasite Cystoisospora suis. B. bigemina produces two daughters per division round by a “binary fission” mechanism whereas C. suis produces daughters through both endodyogeny and multiple internal budding known as endopolygeny. In addition, we provide new data from the causative agent of equine protozoal myeloencephalitis (EPM), Sarcocystis neurona, which also undergoes endopolygeny but differs from C. suis by maintaining a single multiploid nucleus. Overall, we operationally define two principally different division modes: internal budding found in cyst-forming Coccidia (comprising endodyogeny and two forms of endopolygeny) and external budding found in the other parasites studied (comprising the two forms of schizogony, binary fission and multiple fission). Progressive insights into the principles defining the molecular and cellular requirements for internal vs. external budding, as well as variations encountered in sexual stages are discussed. The evolutionary pressures and mechanisms underlying apicomplexan cell division diversification carries relevance across Eukaryota.
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Affiliation(s)
- Marc-Jan Gubbels
- Department of Biology, Boston College, Chestnut Hill, MA, United States
| | - Caroline D Keroack
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Harvard University, Boston, MA, United States
| | - Sriveny Dangoudoubiyam
- Department of Veterinary Science, Gluck Equine Research Center, University of Kentucky, Lexington, KY, United States
| | - Hanna L Worliczek
- Department of Biology, Boston College, Chestnut Hill, MA, United States.,Institute of Parasitology, University of Veterinary Medicine, Vienna, Austria
| | - Aditya S Paul
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Harvard University, Boston, MA, United States
| | - Ciara Bauwens
- Department of Biology, Boston College, Chestnut Hill, MA, United States
| | - Brendan Elsworth
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Harvard University, Boston, MA, United States.,School of Biosciences, University of Melbourne, Melbourne, VIC, Australia
| | - Klemens Engelberg
- Department of Biology, Boston College, Chestnut Hill, MA, United States
| | - Daniel K Howe
- Department of Veterinary Science, Gluck Equine Research Center, University of Kentucky, Lexington, KY, United States
| | - Isabelle Coppens
- Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, United States
| | - Manoj T Duraisingh
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Harvard University, Boston, MA, United States
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12
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The parasitophorous vacuole of the blood-stage malaria parasite. Nat Rev Microbiol 2020; 18:379-391. [PMID: 31980807 DOI: 10.1038/s41579-019-0321-3] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/13/2019] [Indexed: 12/31/2022]
Abstract
The pathology of malaria is caused by infection of red blood cells with unicellular Plasmodium parasites. During blood-stage development, the parasite replicates within a membrane-bound parasitophorous vacuole. A central nexus for host-parasite interactions, this unique parasite shelter functions in nutrient acquisition, subcompartmentalization and the export of virulence factors, making its functional molecules attractive targets for the development of novel intervention strategies to combat the devastating impact of malaria. In this Review, we explore the origin, development, molecular composition and functions of the parasitophorous vacuole of Plasmodium blood stages. We also discuss the relevance of the malaria parasite's intravacuolar lifestyle for successful erythrocyte infection and provide perspectives for future research directions in parasitophorous vacuole biology.
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13
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Geiger M, Brown C, Wichers JS, Strauss J, Lill A, Thuenauer R, Liffner B, Wilcke L, Lemcke S, Heincke D, Pazicky S, Bachmann A, Löw C, Wilson DW, Filarsky M, Burda PC, Zhang K, Junop M, Gilberger TW. Structural Insights Into PfARO and Characterization of its Interaction With PfAIP. J Mol Biol 2019; 432:878-896. [PMID: 31877322 DOI: 10.1016/j.jmb.2019.12.024] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Revised: 12/11/2019] [Accepted: 12/12/2019] [Indexed: 10/25/2022]
Abstract
Apicomplexan parasites contain rhoptries, which are specialized secretory organelles that coordinate host cell invasion. During the process of invasion, rhoptries secrete their contents to facilitate interaction with, and entry into, the host cell. Here, we report the crystal structure of the rhoptry protein Armadillo Repeats-Only (ARO) from the human malaria parasite, Plasmodium falciparum (PfARO). The structure of PfARO comprises five tandem Armadillo-like (ARM) repeats, with adjacent ARM repeats stacked in a head-to-tail orientation resulting in PfARO adopting an elongated curved shape. Interestingly, the concave face of PfARO contains two distinct patches of highly conserved residues that appear to play an important role in protein-protein interaction. We functionally characterized the P. falciparum homolog of ARO interacting protein (PfAIP) and demonstrate that it localizes to the rhoptries. We show that conditional mislocalization of PfAIP leads to deficient red blood cell invasion. Guided by the structure, we identified mutations of PfARO that lead to mislocalization of PfAIP. Using proximity-based biotinylation we probe into PfAIP interacting proteins.
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Affiliation(s)
- Michael Geiger
- Centre for Structural Systems Biology, Notkestraße 85, 22607, Hamburg, Germany; Bernhard Nocht Institute for Tropical Medicine, Bernhard-Nocht-Strasse 74, 20359, Hamburg, Germany; Department of Biology, University of Hamburg, Hamburg, Germany
| | - Chris Brown
- Western University, Department of Biochemistry, London, ON, Canada
| | - Jan Stephan Wichers
- Centre for Structural Systems Biology, Notkestraße 85, 22607, Hamburg, Germany; Bernhard Nocht Institute for Tropical Medicine, Bernhard-Nocht-Strasse 74, 20359, Hamburg, Germany; Department of Biology, University of Hamburg, Hamburg, Germany
| | - Jan Strauss
- Centre for Structural Systems Biology, Notkestraße 85, 22607, Hamburg, Germany; Bernhard Nocht Institute for Tropical Medicine, Bernhard-Nocht-Strasse 74, 20359, Hamburg, Germany; Department of Biology, University of Hamburg, Hamburg, Germany
| | - Andrés Lill
- Centre for Structural Systems Biology, Notkestraße 85, 22607, Hamburg, Germany; Department of Biology, University of Hamburg, Hamburg, Germany
| | - Roland Thuenauer
- Centre for Structural Systems Biology, Notkestraße 85, 22607, Hamburg, Germany; Department of Biology, University of Hamburg, Hamburg, Germany
| | - Benjamin Liffner
- Research Centre for Infectious Diseases, School of Biological Sciences, University of Adelaide, Adelaide, Australia
| | - Louisa Wilcke
- Centre for Structural Systems Biology, Notkestraße 85, 22607, Hamburg, Germany; Bernhard Nocht Institute for Tropical Medicine, Bernhard-Nocht-Strasse 74, 20359, Hamburg, Germany
| | - Sarah Lemcke
- Centre for Structural Systems Biology, Notkestraße 85, 22607, Hamburg, Germany; Bernhard Nocht Institute for Tropical Medicine, Bernhard-Nocht-Strasse 74, 20359, Hamburg, Germany; Department of Biology, University of Hamburg, Hamburg, Germany
| | - Dorothee Heincke
- Centre for Structural Systems Biology, Notkestraße 85, 22607, Hamburg, Germany; Bernhard Nocht Institute for Tropical Medicine, Bernhard-Nocht-Strasse 74, 20359, Hamburg, Germany; Department of Biology, University of Hamburg, Hamburg, Germany
| | - Samuel Pazicky
- Centre for Structural Systems Biology, Notkestraße 85, 22607, Hamburg, Germany; Molecular Biology Laboratory (EMBL), Hamburg Unit c/o Deutsches Elektronen Synchrotron (DESY), Notkestrasse 85, 22607, Hamburg, Germany
| | - Anna Bachmann
- Centre for Structural Systems Biology, Notkestraße 85, 22607, Hamburg, Germany; Bernhard Nocht Institute for Tropical Medicine, Bernhard-Nocht-Strasse 74, 20359, Hamburg, Germany; Department of Biology, University of Hamburg, Hamburg, Germany
| | - Christian Löw
- Centre for Structural Systems Biology, Notkestraße 85, 22607, Hamburg, Germany; Molecular Biology Laboratory (EMBL), Hamburg Unit c/o Deutsches Elektronen Synchrotron (DESY), Notkestrasse 85, 22607, Hamburg, Germany
| | - Danny William Wilson
- Research Centre for Infectious Diseases, School of Biological Sciences, University of Adelaide, Adelaide, Australia; Burnet Institute, 85 Commercial Road, Melbourne, 3004, Victoria, Australia
| | - Michael Filarsky
- Centre for Structural Systems Biology, Notkestraße 85, 22607, Hamburg, Germany; Department of Biology, University of Hamburg, Hamburg, Germany
| | - Paul-Christian Burda
- Centre for Structural Systems Biology, Notkestraße 85, 22607, Hamburg, Germany; Bernhard Nocht Institute for Tropical Medicine, Bernhard-Nocht-Strasse 74, 20359, Hamburg, Germany; Department of Biology, University of Hamburg, Hamburg, Germany
| | - Kun Zhang
- Western University, Department of Biochemistry, London, ON, Canada
| | - Murray Junop
- Western University, Department of Biochemistry, London, ON, Canada.
| | - Tim Wolf Gilberger
- Centre for Structural Systems Biology, Notkestraße 85, 22607, Hamburg, Germany; Bernhard Nocht Institute for Tropical Medicine, Bernhard-Nocht-Strasse 74, 20359, Hamburg, Germany; Department of Biology, University of Hamburg, Hamburg, Germany.
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14
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Hammarton TC. Who Needs a Contractile Actomyosin Ring? The Plethora of Alternative Ways to Divide a Protozoan Parasite. Front Cell Infect Microbiol 2019; 9:397. [PMID: 31824870 PMCID: PMC6881465 DOI: 10.3389/fcimb.2019.00397] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Accepted: 11/06/2019] [Indexed: 01/21/2023] Open
Abstract
Cytokinesis, or the division of the cytoplasm, following the end of mitosis or meiosis, is accomplished in animal cells, fungi, and amoebae, by the constriction of an actomyosin contractile ring, comprising filamentous actin, myosin II, and associated proteins. However, despite this being the best-studied mode of cytokinesis, it is restricted to the Opisthokonta and Amoebozoa, since members of other evolutionary supergroups lack myosin II and must, therefore, employ different mechanisms. In particular, parasitic protozoa, many of which cause significant morbidity and mortality in humans and animals as well as considerable economic losses, employ a wide diversity of mechanisms to divide, few, if any, of which involve myosin II. In some cases, cell division is not only myosin II-independent, but actin-independent too. Mechanisms employed range from primitive mechanical cell rupture (cytofission), to motility- and/or microtubule remodeling-dependent mechanisms, to budding involving the constriction of divergent contractile rings, to hijacking host cell division machinery, with some species able to utilize multiple mechanisms. Here, I review current knowledge of cytokinesis mechanisms and their molecular control in mammalian-infective parasitic protozoa from the Excavata, Alveolata, and Amoebozoa supergroups, highlighting their often-underappreciated diversity and complexity. Billions of people and animals across the world are at risk from these pathogens, for which vaccines and/or optimal treatments are often not available. Exploiting the divergent cell division machinery in these parasites may provide new avenues for the treatment of protozoal disease.
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Affiliation(s)
- Tansy C Hammarton
- Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, United Kingdom
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15
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Rudlaff RM, Kraemer S, Streva VA, Dvorin JD. An essential contractile ring protein controls cell division in Plasmodium falciparum. Nat Commun 2019; 10:2181. [PMID: 31097714 PMCID: PMC6522492 DOI: 10.1038/s41467-019-10214-z] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Accepted: 04/23/2019] [Indexed: 11/09/2022] Open
Abstract
During the blood stage of human malaria, Plasmodium falciparum parasites divide by schizogony-a process wherein components for several daughter cells are produced within a common cytoplasm and then segmentation, a synchronized cytokinesis, produces individual invasive daughters. The basal complex is hypothesized to be required for segmentation, acting as a contractile ring to establish daughter cell boundaries. Here we identify an essential component of the basal complex which we name PfCINCH. Using three-dimensional reconstructions of parasites at electron microscopy resolution, we show that while parasite organelles form and divide normally, PfCINCH-deficient parasites develop inviable conjoined daughters that contain components for multiple cells. Through biochemical evaluation of the PfCINCH-containing complex, we discover multiple previously undescribed basal complex proteins. Therefore, this work provides genetic evidence that the basal complex is required for precise segmentation and lays the groundwork for a mechanistic understanding of how the parasite contractile ring drives cell division.
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Affiliation(s)
- Rachel M Rudlaff
- Biological and Biomedical Sciences, Harvard Medical School, Boston, MA, 02115, USA
- Division of Infectious Diseases, Boston Children's Hospital, Boston, MA, 02115, USA
| | - Stephan Kraemer
- Center for Nanoscale Systems, Harvard University, Boston, MA, 02138, USA
| | - Vincent A Streva
- Division of Infectious Diseases, Boston Children's Hospital, Boston, MA, 02115, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA, 02115, USA
| | - Jeffrey D Dvorin
- Division of Infectious Diseases, Boston Children's Hospital, Boston, MA, 02115, USA.
- Department of Pediatrics, Harvard Medical School, Boston, MA, 02115, USA.
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16
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Hallée S, Counihan NA, Matthews K, Koning‐Ward TF, Richard D. The malaria parasite
Plasmodium falciparum
Sortilin is essential for merozoite formation and apical complex biogenesis. Cell Microbiol 2018; 20:e12844. [DOI: 10.1111/cmi.12844] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Revised: 02/22/2018] [Accepted: 03/17/2018] [Indexed: 12/25/2022]
Affiliation(s)
- Stéphanie Hallée
- Centre de recherche en infectiologieCHU de Québec‐Université Laval Quebec City QC Canada
| | | | - Kathryn Matthews
- School of MedicineDeakin University Waurn Ponds 3216 VIC Australia
| | | | - Dave Richard
- Centre de recherche en infectiologieCHU de Québec‐Université Laval Quebec City QC Canada
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17
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Saini E, Zeeshan M, Brady D, Pandey R, Kaiser G, Koreny L, Kumar P, Thakur V, Tatiya S, Katris NJ, Limenitakis RS, Kaur I, Green JL, Bottrill AR, Guttery DS, Waller RF, Heussler V, Holder AA, Mohmmed A, Malhotra P, Tewari R. Photosensitized INA-Labelled protein 1 (PhIL1) is novel component of the inner membrane complex and is required for Plasmodium parasite development. Sci Rep 2017; 7:15577. [PMID: 29138437 PMCID: PMC5686188 DOI: 10.1038/s41598-017-15781-z] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 11/01/2017] [Indexed: 11/09/2022] Open
Abstract
Plasmodium parasites, the causative agents of malaria, possess a distinctive membranous structure of flattened alveolar vesicles supported by a proteinaceous network, and referred to as the inner membrane complex (IMC). The IMC has a role in actomyosin-mediated motility and host cell invasion. Here, we examine the location, protein interactome and function of PhIL1, an IMC-associated protein on the motile and invasive stages of both human and rodent parasites. We show that PhIL1 is located in the IMC in all three invasive (merozoite, ookinete-, and sporozoite) stages of development, as well as in the male gametocyte and locates both at the apical and basal ends of ookinete and sporozoite stages. Proteins interacting with PhIL1 were identified, showing that PhIL1 was bound to only some proteins present in the glideosome motor complex (GAP50, GAPM1–3) of both P. falciparum and P. berghei. Analysis of PhIL1 function using gene targeting approaches indicated that the protein is required for both asexual and sexual stages of development. In conclusion, we show that PhIL1 is required for development of all zoite stages of Plasmodium and it is part of a novel protein complex with an overall composition overlapping with but different to that of the glideosome.
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Affiliation(s)
- Ekta Saini
- International Centre for Genetic Engineering and Biotechnology, New Delhi, 110067, India
| | - Mohammad Zeeshan
- School of Life Sciences, University of Nottingham, Nottingham, NG72UH, UK
| | - Declan Brady
- School of Life Sciences, University of Nottingham, Nottingham, NG72UH, UK
| | - Rajan Pandey
- International Centre for Genetic Engineering and Biotechnology, New Delhi, 110067, India
| | - Gesine Kaiser
- Institute of Cell Biology, University of Bern, Bern, 3012, Switzerland
| | - Ludek Koreny
- Department of Biochemistry, University of Cambridge, Cambridge, CB2 1QW, UK
| | - Pradeep Kumar
- International Centre for Genetic Engineering and Biotechnology, New Delhi, 110067, India
| | - Vandana Thakur
- International Centre for Genetic Engineering and Biotechnology, New Delhi, 110067, India
| | - Shreyansh Tatiya
- International Centre for Genetic Engineering and Biotechnology, New Delhi, 110067, India
| | - Nicholas J Katris
- Department of Biochemistry, University of Cambridge, Cambridge, CB2 1QW, UK
| | | | - Inderjeet Kaur
- International Centre for Genetic Engineering and Biotechnology, New Delhi, 110067, India
| | | | - Andrew R Bottrill
- Protein and Nucleic Acid Chemistry Laboratory, University of Leicester, Leicester, LE2 7LX, UK
| | - David S Guttery
- Department of Cancer studies, University of Leicester, Leicester, LE2 7LX, UK
| | - Ross F Waller
- Department of Biochemistry, University of Cambridge, Cambridge, CB2 1QW, UK
| | - Volker Heussler
- Institute of Cell Biology, University of Bern, Bern, 3012, Switzerland
| | | | - Asif Mohmmed
- International Centre for Genetic Engineering and Biotechnology, New Delhi, 110067, India
| | - Pawan Malhotra
- International Centre for Genetic Engineering and Biotechnology, New Delhi, 110067, India.
| | - Rita Tewari
- School of Life Sciences, University of Nottingham, Nottingham, NG72UH, UK.
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18
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A Plasmodium plasma membrane reporter reveals membrane dynamics by live-cell microscopy. Sci Rep 2017; 7:9740. [PMID: 28851956 PMCID: PMC5575152 DOI: 10.1038/s41598-017-09569-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Accepted: 07/26/2017] [Indexed: 11/08/2022] Open
Abstract
During asexual replication within the Anopheles mosquito and their vertebrate host, Plasmodium parasites depend on the generation of a massive amount of new plasma membrane to produce thousands of daughter parasites. How the parasite plasma membrane (PPM) is formed has mostly been studied by electron microscopy, which does not allow an insight into the dynamics of this process. We generated a Plasmodium berghei reporter parasite line by GFP-tagging of a non-essential PPM-localized protein, and followed plasma membrane development in living parasites through the entire Plasmodium life cycle. By generating double-fluorescent parasites in which the PPM is visualized in combination with the parasite endoplasmic reticulum, we show that membrane contact sites are formed between both membrane systems during oocyst and liver stage development that might be used to deliver lipids to the dramatically expanding PPM. In conclusion, we have established a powerful tool to follow PPM development in living parasites, which promises to greatly expand our knowledge of membrane biology in the Plasmodium parasite.
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19
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An evolutionarily conserved SSNA1/DIP13 homologue is a component of both basal and apical complexes of Toxoplasma gondii. Sci Rep 2016; 6:27809. [PMID: 27324377 PMCID: PMC4914967 DOI: 10.1038/srep27809] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Accepted: 05/25/2016] [Indexed: 12/19/2022] Open
Abstract
Microtubule-based cytoskeletal structures have fundamental roles in several essential eukaryotic processes, including transport of intracellular constituents as well as ciliary and flagellar mobility. Temporal and spatial organisation of microtubules is determined by microtubule organising centers and a number of appendages and accessory proteins. Members of the SSNA1/DIP13 family are coiled coil proteins that are known to localise to microtubular structures like centrosomes and flagella, but are otherwise poorly characterised. We have identified a homologue of SSNA1/DIP13 in the parasitic protist Toxoplasma gondii and found it localises to parasite-specific cytoskeletal structures: the conoid in the apical complex of mature and dividing cells, and the basal complex in elongating daughter cells during cell division. This protein is dispensable for parasite growth in vitro. However, quite remarkably, this coiled coil protein is able to self-associate into higher order structures both in vitro and in vivo, and its overexpression is impairing parasite division.
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