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Klinger CM, Jimenez-Ruiz E, Mourier T, Klingl A, Lemgruber L, Pain A, Dacks JB, Meissner M. Evolutionary analysis identifies a Golgi pathway and correlates lineage-specific factors with endomembrane organelle emergence in apicomplexans. Cell Rep 2024; 43:113740. [PMID: 38363682 DOI: 10.1016/j.celrep.2024.113740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Revised: 12/20/2023] [Accepted: 01/18/2024] [Indexed: 02/18/2024] Open
Abstract
The organelle paralogy hypothesis (OPH) aims to explain the evolution of non-endosymbiotically derived organelles. It predicts that lineage-specific pathways or organelles should result when identity-encoding membrane-trafficking components duplicate and co-evolve. Here, we investigate the presence of such lineage-specific membrane-trafficking machinery paralogs in Apicomplexa, a globally important parasitic lineage. We are able to identify 18 paralogs of known membrane-trafficking machinery, in several cases co-incident with the presence of new endomembrane organelles in apicomplexans or their parent lineage, the Alveolata. Moreover, focused analysis of the apicomplexan Arf-like small GTPases (i.e., ArlX3) revealed a specific post-Golgi trafficking pathway. This pathway appears involved in delivery of proteins to micronemes and rhoptries, with knockdown demonstrating reduced invasion capacity. Overall, our data have identified an unforeseen post-Golgi trafficking pathway in apicomplexans and are consistent with the OPH mechanism acting to produce endomembrane pathways or organelles at various evolutionary stages across the alveolate lineage.
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Affiliation(s)
- Christen M Klinger
- Division of Infectious Diseases, Department of Medicine and Department of Biological Sciences, University of Alberta, Edmonton, AB, Canada; Women and Children's Health Research Institute, University of Alberta, Edmonton, AB, Canada
| | - Elena Jimenez-Ruiz
- Experimental Parasitology, Department of Veterinary Sciences, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität, LMU, Munich, Germany
| | - Tobias Mourier
- Pathogen Genomics Laboratory, Bioscience Programme, Biological, and Environmental Sciences and Engineering (BESE) Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Andreas Klingl
- Pflanzliche Entwicklungsbiologie, Biozentrum der Ludwig-Maximilians-Universität, Munich, Germany
| | - Leandro Lemgruber
- Cellular Analysis Facility, College of Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow, UK
| | - Arnab Pain
- Pathogen Genomics Laboratory, Bioscience Programme, Biological, and Environmental Sciences and Engineering (BESE) Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia; International Institute for Zoonosis Control, GI-CoRE, Hokkaido University, Sapporo, Japan
| | - Joel B Dacks
- Division of Infectious Diseases, Department of Medicine and Department of Biological Sciences, University of Alberta, Edmonton, AB, Canada; Women and Children's Health Research Institute, University of Alberta, Edmonton, AB, Canada; Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic; Centre for Life's Origin and Evolution, Department of Genetics, Evolution & Environment, University College London, London, UK.
| | - Markus Meissner
- Experimental Parasitology, Department of Veterinary Sciences, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität, LMU, Munich, Germany.
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2
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Wagner M, Song Y, Jiménez-Ruiz E, Härtle S, Meissner M. The SUN-like protein TgSLP1 is essential for nuclear division in the apicomplexan parasite Toxoplasma gondii. J Cell Sci 2023; 136:jcs260337. [PMID: 37815466 PMCID: PMC10629696 DOI: 10.1242/jcs.260337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Accepted: 09/22/2023] [Indexed: 10/11/2023] Open
Abstract
Connections between the nucleus and the cytoskeleton are important for positioning and division of the nucleus. In most eukaryotes, the linker of nucleoskeleton and cytoskeleton (LINC) complex spans the outer and inner nuclear membranes and connects the nucleus to the cytoskeleton. In opisthokonts, it is composed of Klarsicht, ANC-1 and Syne homology (KASH) domain proteins and Sad1 and UNC-84 (SUN) domain proteins. Given that the nucleus is positioned at the posterior pole of Toxoplasma gondii, we speculated that apicomplexan parasites must have a similar mechanism that integrates the nucleus and the cytoskeleton. Here, we identified three UNC family proteins in the genome of the apicomplexan parasite T. gondii. Whereas the UNC-50 protein TgUNC1 localised to the Golgi and appeared to be not essential for the parasite, the SUN domain protein TgSLP2 showed a diffuse pattern throughout the parasite. The second SUN domain protein, TgSLP1, was expressed in a cell cycle-dependent manner and was localised close to the mitotic spindle and, more detailed, at the kinetochore. We demonstrate that conditional knockout of TgSLP1 leads to failure of nuclear division and loss of centrocone integrity.
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Affiliation(s)
- Mirjam Wagner
- Experimental Parasitology, Department of Veterinary Sciences, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität, LMU, Munich, 82152, Planegg, Germany
| | - Yuan Song
- Experimental Parasitology, Department of Veterinary Sciences, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität, LMU, Munich, 82152, Planegg, Germany
| | - Elena Jiménez-Ruiz
- Experimental Parasitology, Department of Veterinary Sciences, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität, LMU, Munich, 82152, Planegg, Germany
| | - Sonja Härtle
- Department of Veterinary Sciences, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität, LMU, Munich, 82152, Planegg, Germany
| | - Markus Meissner
- Experimental Parasitology, Department of Veterinary Sciences, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität, LMU, Munich, 82152, Planegg, Germany
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3
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Nyonda MA, Kloehn J, Sosnowski P, Krishnan A, Lentini G, Maco B, Marq JB, Hannich JT, Hopfgartner G, Soldati-Favre D. Ceramide biosynthesis is critical for establishment of the intracellular niche of Toxoplasma gondii. Cell Rep 2022; 40:111224. [PMID: 35977499 PMCID: PMC9396527 DOI: 10.1016/j.celrep.2022.111224] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2021] [Revised: 06/06/2022] [Accepted: 07/26/2022] [Indexed: 11/15/2022] Open
Abstract
Toxoplasma gondii possesses sphingolipid synthesis capabilities and is equipped to salvage lipids from its host. The contribution of these two routes of lipid acquisition during parasite development is unclear. As part of a complete ceramide synthesis pathway, T. gondii expresses two serine palmitoyltransferases (TgSPT1 and TgSPT2) and a dihydroceramide desaturase. After deletion of these genes, we determine their role in parasite development in vitro and in vivo during acute and chronic infection. Detailed phenotyping through lipidomic approaches reveal a perturbed sphingolipidome in these mutants, characterized by a drastic reduction in ceramides and ceramide phosphoethanolamines but not sphingomyelins. Critically, parasites lacking TgSPT1 display decreased fitness, marked by reduced growth rates and a selective defect in rhoptry discharge in the form of secretory vesicles, causing an invasion defect. Disruption of de novo ceramide synthesis modestly affects acute infection in vivo but severely reduces cyst burden in the brain of chronically infected mice. De novo sphingolipid synthesis is active at the ER of Toxoplasma gondii T. gondii scavenges sphingomyelins but synthesizes ceramide phosphoethanolamines TgSPT1 is required for establishment of the intracellular niche during invasion Defects in T. gondii sphingolipid synthesis affect chronic infection in vivo
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Affiliation(s)
- Mary Akinyi Nyonda
- Department of Microbiology and Molecular Medicine, University of Geneva, Geneva, Switzerland
| | - Joachim Kloehn
- Department of Microbiology and Molecular Medicine, University of Geneva, Geneva, Switzerland
| | - Piotr Sosnowski
- Life Sciences Mass Spectrometry, Department of Inorganic and Analytical Chemistry, University of Geneva, 24 Quai Ernest Ansermet, 1211 Geneva 4, Switzerland
| | - Aarti Krishnan
- Department of Microbiology and Molecular Medicine, University of Geneva, Geneva, Switzerland
| | - Gaëlle Lentini
- Department of Microbiology and Molecular Medicine, University of Geneva, Geneva, Switzerland
| | - Bohumil Maco
- Department of Microbiology and Molecular Medicine, University of Geneva, Geneva, Switzerland
| | - Jean-Baptiste Marq
- Department of Microbiology and Molecular Medicine, University of Geneva, Geneva, Switzerland
| | - J Thomas Hannich
- Department of Biochemistry, NCCR Chemical Biology, University of Geneva, Quai Ernest-Ansermet 30, Geneva, Switzerland
| | - Gerard Hopfgartner
- Life Sciences Mass Spectrometry, Department of Inorganic and Analytical Chemistry, University of Geneva, 24 Quai Ernest Ansermet, 1211 Geneva 4, Switzerland
| | - Dominique Soldati-Favre
- Department of Microbiology and Molecular Medicine, University of Geneva, Geneva, Switzerland.
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4
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Global phosphoproteome analysis reveals significant differences between sporulated oocysts of virulent and avirulent strains of Toxoplasma gondii. Microb Pathog 2021; 161:105240. [PMID: 34655729 DOI: 10.1016/j.micpath.2021.105240] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 09/15/2021] [Accepted: 10/06/2021] [Indexed: 11/23/2022]
Abstract
In this study, the differences in the phosphoproteomic landscape of sporulated oocysts between virulent and avirulent strains of Toxoplasma gondii were examined using a global phosphoproteomics approach. Phosphopeptides from sporulated oocysts of the virulent PYS strain (Chinese ToxoDB#9) and the avirulent PRU strain (type II) were enriched by titanium dioxide (TiO2) affinity chromatography and quantified using IBT approach. A total of 10,645 unique phosphopeptides, 8181 nonredundant phosphorylation sites and 2792 phosphoproteins were identified. We also detected 4129 differentially expressed phosphopeptides (DEPs) between sporulated oocysts of PYS strain and PRU strain (|log1.5 fold change| > 1 and p < 0.05), including 2485 upregulated and 1644 downregulated phosphopeptides. Motif analysis identified 24 motifs from the upregulated phosphorylated peptides including 22 serine motifs and two threonine motifs (TPE and TP), and 15 motifs from the downregulated phosphorylated peptides including 12 serine motifs and three threonine motifs (TP, RxxT and KxxT) in PYS strain when comparing PYS strain to PRU strain. Several kinases were consistent with motifs of overrepresented phosphopeptides, such as PKA, PKG, CKII, IKK, MAPK, EGFR, INSR, Jak, Syk, Src, Ab1. GO enrichment, KEGG pathway analysis and STRING analysis revealed DEPs significantly enriched in many biological processes and pathways. Kinase related network analysis showed that AGC kinase was the most connected kinase peptide. Our findings reveal significant difference in phosphopeptide profiles of sporulated oocysts between virulent and avirulent T. gondii strains, providing new resources for further elucidation of the mechanisms underpinning the virulence of T. gondii.
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Cao S, Yang J, Fu J, Chen H, Jia H. The Dissection of SNAREs Reveals Key Factors for Vesicular Trafficking to the Endosome-like Compartment and Apicoplast via the Secretory System in Toxoplasma gondii. mBio 2021; 12:e0138021. [PMID: 34340555 PMCID: PMC8406237 DOI: 10.1128/mbio.01380-21] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Accepted: 07/02/2021] [Indexed: 12/18/2022] Open
Abstract
Vesicular trafficking is a fundamental cellular process involved in material transport in eukaryotes, but the diversity of the intracellular compartments has prevented researchers from obtaining a clear understanding of the specific functions of vesicular trafficking factors, including SNAREs, tethers, and Rab GTPases, in Apicomplexa. In this study, we analyzed the localization of SNAREs and investigated their roles in vesicular trafficking in Toxoplasma gondii. Our results revealed the specific localizations of SNAREs in the endoplasmic reticulum (ER) (T. gondii Stx18 [TgStx18] and TgStx19), Golgi stacks (TgGS27), and endosome-like compartment (TgStx10 and TgStx12). The conditional ablation of ER- and Golgi-residing SNAREs caused severe defects in the secretory system. Most importantly, we found an R-SNARE (TgVAMP4-2) that is targeted to the apicoplast; to our knowledge, this work provides the first information showing a SNARE protein on endosymbiotic organelles and functioning in vesicular trafficking in eukaryotes. Conditional knockout of TgVAMP4-2 blocked the entrance of TgCPN60, TgACP, TgATrx2, and TgATrx1 into the apicoplast and interfered with the targeting of TgAPT1 and TgFtsH1 to the outermost membrane of the apicoplast. Together, our findings revealed the functions of SNAREs in the secretory system and the transport of nucleus-encoded proteins to an endosymbiotic organelle in a model organism of Apicomplexa. IMPORTANCE SNAREs are essential for the fusion of the transport vesicles and target membranes and, thus, provide perfect targets for obtaining a global view of the vesicle transport system. In this study, we report that a novel Qc-SNARE (TgStx19) instead of Use1 is located at the ER and acts as a partner of TgStx18 in T. gondii. TgGS27 and the tethering complex TRAPP III are conserved and critical for the biogenesis of the Golgi complex in T. gondii. A novel R-SNARE, TgVAMP4-2, is found on the outermost membrane of the apicoplast. The transport of NEAT proteins into the secondary endosymbiotic organelle depends on its function. To our knowledge, this work provides the first mention of a SNARE located on endosymbiotic organelles that functions in vesicular trafficking in eukaryotes.
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Affiliation(s)
- Shinuo Cao
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, People’s Republic of China
| | - Juan Yang
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, People’s Republic of China
| | - Jiawen Fu
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, People’s Republic of China
| | - Heming Chen
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, People’s Republic of China
| | - Honglin Jia
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, People’s Republic of China
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6
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Ren B, Kong P, Hedar F, Brouwers JF, Gupta N. Phosphatidylinositol synthesis, its selective salvage, and inter-regulation of anionic phospholipids in Toxoplasma gondii. Commun Biol 2020; 3:750. [PMID: 33303967 PMCID: PMC7728818 DOI: 10.1038/s42003-020-01480-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 11/11/2020] [Indexed: 02/07/2023] Open
Abstract
Phosphatidylinositol (PtdIns) serves as an integral component of eukaryotic membranes; however, its biosynthesis in apicomplexan parasites remains poorly understood. Here we show that Toxoplasma gondii-a common intracellular pathogen of humans and animals-can import and co-utilize myo-inositol with the endogenous CDP-diacylglycerol to synthesize PtdIns. Equally, the parasite harbors a functional PtdIns synthase (PIS) containing a catalytically-vital CDP-diacylglycerol phosphotransferase motif in the Golgi apparatus. Auxin-induced depletion of PIS abrogated the lytic cycle of T. gondii in human cells due to defects in cell division, gliding motility, invasion, and egress. Isotope labeling of the PIS mutant in conjunction with lipidomics demonstrated de novo synthesis of specific PtdIns species, while revealing the salvage of other lipid species from the host cell. Not least, the mutant showed decline in phosphatidylthreonine, and elevation of selected phosphatidylserine and phosphatidylglycerol species, indicating a rerouting of CDP-diacylglycerol and homeostatic inter-regulation of anionic phospholipids upon knockdown of PIS. In conclusion, strategic allocation of own and host-derived PtdIns species to gratify its metabolic demand features as a notable adaptive trait of T. gondii. Conceivably, the dependence of T. gondii on de novo lipid synthesis and scavenging can be exploited to develop new anti-infectives.
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Affiliation(s)
- Bingjian Ren
- Department of Molecular Parasitology, Faculty of Life Sciences, Humboldt University, Berlin, Germany
| | - Pengfei Kong
- Department of Molecular Parasitology, Faculty of Life Sciences, Humboldt University, Berlin, Germany
| | - Fatima Hedar
- Department of Molecular Parasitology, Faculty of Life Sciences, Humboldt University, Berlin, Germany
| | - Jos F Brouwers
- Center for Molecular Medicine, University Medical Center, Utrecht, The Netherlands
| | - Nishith Gupta
- Department of Molecular Parasitology, Faculty of Life Sciences, Humboldt University, Berlin, Germany.
- Department of Biological Sciences, Birla Institute of Technology and Science Pilani (BITS-P), Hyderabad, India.
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7
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iTRAQ-based proteome profiling of hyposaline responses in zygotes of the Pacific oyster Crassostrea gigas. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY D-GENOMICS & PROTEOMICS 2018; 30:14-24. [PMID: 30771561 DOI: 10.1016/j.cbd.2018.12.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2018] [Revised: 12/06/2018] [Accepted: 12/07/2018] [Indexed: 11/22/2022]
Abstract
Low salinity treatment is proven to be the practical polyploidy inducing method for shellfish with advantages of lower cost, higher operability and reliable food security. However, little is known about the possible molecular mechanism of hypotonic induction. In this study, isobaric tags for relative and absolute quantitation (iTRAQ) based proteomic profiling was pursued to investigate the responses of zygotes of the Pacific oyster Crassostrea gigas to low salinity. A total of 2235 proteins were identified and 87 proteins were considered differentially expressed, of which 14 were up-regulated and 69 were down-regulated. Numerous functional proteins including ADP ribosylation factor 2, DNA repair protein Rad50, splicing factor 3B, tubulin-specific Chaperone D were significantly changed in abundance, and were involved in various biology processes including energy generation, vesicle trafficking, DNA/RNA/protein metabolism and cytoskeleton modification, indicating the prominent modulation of cell division and embryonic development. Parallel reaction monitoring (PRM) analyses were carried out for validation of the expression levels of differentially expressed proteins (DEPs), which indicated high reliability of the proteomic results. Our study not only demonstrated the proteomic alterations in oyster zygotes under low salinity, but also provided, in part, clues to the relatively lower hatching rate and higher mortality of induced larvae. Above all, this study presents a valuable foundation for further studies on mechanisms of hypotonic induction.
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8
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Venugopal K, Marion S. Secretory organelle trafficking in Toxoplasma gondii: A long story for a short travel. Int J Med Microbiol 2018; 308:751-760. [DOI: 10.1016/j.ijmm.2018.07.007] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Revised: 07/10/2018] [Accepted: 07/15/2018] [Indexed: 12/15/2022] Open
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9
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Wang S, Xie K, Xu G, Zhou H, Guo Q, Wu J, Liao Z, Liu N, Wang Y, Liu Y. Plant G proteins interact with endoplasmic reticulum luminal protein receptors to regulate endoplasmic reticulum retrieval. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2018; 60:541-561. [PMID: 29573168 DOI: 10.1111/jipb.12648] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2018] [Accepted: 03/12/2018] [Indexed: 06/08/2023]
Abstract
Maintaining endoplasmic reticulum (ER) homeostasis is essential for the production of biomolecules. ER retrieval, i.e., the retrograde transport of compounds from the Golgi to the ER, is one of the pathways that ensures ER homeostasis. However, the mechanisms underlying the regulation of ER retrieval in plants remain largely unknown. Plant ERD2-like proteins (ERD2s) were recently suggested to function as ER luminal protein receptors that mediate ER retrieval. Here, we demonstrate that heterotrimeric G protein signaling is involved in ERD2-mediated ER retrieval. We show that ERD2s interact with the heterotrimeric G protein Gα and Gγ subunits at the Golgi. Silencing of Gα, Gβ, or Gγ increased the retention of ER luminal proteins. Furthermore, overexpression of Gα, Gβ, or Gγ caused ER luminal proteins to escape from the ER, as did the co-silencing of ERD2a and ERD2b. These results suggest that G proteins interact with ER luminal protein receptors to regulate ER retrieval.
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Affiliation(s)
- Shanshan Wang
- MOE Key Laboratory of Bioinformatics, Center for Plant Biology, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Ke Xie
- Advanced Biotechnology and Application Research Center, School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Guoyong Xu
- The Institute for Advanced Studies (IAS), Wuhan University, Wuhan 430072, China
| | - Huarui Zhou
- MOE Key Laboratory of Bioinformatics, Center for Plant Biology, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Qiang Guo
- MOE Key Laboratory of Bioinformatics, Center for Plant Biology, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Jingyi Wu
- MOE Key Laboratory of Bioinformatics, Center for Plant Biology, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Zengwei Liao
- MOE Key Laboratory of Bioinformatics, Center for Plant Biology, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Na Liu
- MOE Key Laboratory of Bioinformatics, Center for Plant Biology, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Yan Wang
- MOE Key Laboratory of Bioinformatics, Center for Plant Biology, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Yule Liu
- MOE Key Laboratory of Bioinformatics, Center for Plant Biology, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
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10
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McGovern OL, Rivera-Cuevas Y, Kannan G, Narwold AJ, Carruthers VB. Intersection of endocytic and exocytic systems in Toxoplasma gondii. Traffic 2018; 19:336-353. [PMID: 29437275 DOI: 10.1111/tra.12556] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Revised: 02/09/2018] [Accepted: 02/10/2018] [Indexed: 12/12/2022]
Abstract
Host cytosolic proteins are endocytosed by Toxoplasma gondii and degraded in its lysosome-like compartment, the vacuolar compartment (VAC), but the dynamics and route of endocytic trafficking remain undefined. Conserved endocytic components and plant-like features suggest T. gondii endocytic trafficking involves transit through early and late endosome-like compartments (ELCs) and potentially the trans-Golgi network (TGN) as in plants. However, exocytic trafficking to regulated secretory organelles, micronemes and rhoptries, also proceeds through ELCs and requires classical endocytic components, including a dynamin-related protein, DrpB. Here, we show that host cytosolic proteins are endocytosed within 7 minutes post-invasion, trafficked through ELCs en route to the VAC, and degraded within 30 minutes. We could not definitively interpret if ingested protein is trafficked through the TGN. We also found that parasites ingest material from the host cytosol throughout the parasite cell cycle. Ingested host proteins colocalize with immature microneme proteins, proM2AP and proMIC5, in transit to the micronemes, but not with the immature rhoptry protein proRON4, indicating that endocytic trafficking of ingested protein intersects with exocytic trafficking of microneme proteins. Finally, we show that conditional expression of a DrpB dominant negative mutant increases T. gondii ingestion of host-derived proteins, suggesting that DrpB is not required for parasite endocytosis.
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Affiliation(s)
- Olivia L McGovern
- Department of Microbiology and Immunology, University of Michigan School of Medicine, Ann Arbor, Michigan
| | - Yolanda Rivera-Cuevas
- Department of Microbiology and Immunology, University of Michigan School of Medicine, Ann Arbor, Michigan
| | - Geetha Kannan
- Department of Microbiology and Immunology, University of Michigan School of Medicine, Ann Arbor, Michigan
| | - Andrew J Narwold
- Department of Microbiology and Immunology, University of Michigan School of Medicine, Ann Arbor, Michigan
| | - Vern B Carruthers
- Department of Microbiology and Immunology, University of Michigan School of Medicine, Ann Arbor, Michigan
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11
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Mina JG, Thye JK, Alqaisi AQI, Bird LE, Dods RH, Grøftehauge MK, Mosely JA, Pratt S, Shams-Eldin H, Schwarz RT, Pohl E, Denny PW. Functional and phylogenetic evidence of a bacterial origin for the first enzyme in sphingolipid biosynthesis in a phylum of eukaryotic protozoan parasites. J Biol Chem 2017; 292:12208-12219. [PMID: 28578314 PMCID: PMC5519370 DOI: 10.1074/jbc.m117.792374] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Revised: 06/01/2017] [Indexed: 11/06/2022] Open
Abstract
Toxoplasma gondii is an obligate, intracellular eukaryotic apicomplexan protozoan parasite that can cause fetal damage and abortion in both animals and humans. Sphingolipids are essential and ubiquitous components of eukaryotic membranes that are both synthesized and scavenged by the Apicomplexa. Here we report the identification, isolation, and analyses of the Toxoplasma serine palmitoyltransferase, an enzyme catalyzing the first and rate-limiting step in sphingolipid biosynthesis: the condensation of serine and palmitoyl-CoA. In all eukaryotes analyzed to date, serine palmitoyltransferase is a highly conserved heterodimeric enzyme complex. However, biochemical and structural analyses demonstrated the apicomplexan orthologue to be a functional, homodimeric serine palmitoyltransferase localized to the endoplasmic reticulum. Furthermore, phylogenetic studies indicated that it was evolutionarily related to the prokaryotic serine palmitoyltransferase, identified in the Sphingomonadaceae as a soluble homodimeric enzyme. Therefore this enzyme, conserved throughout the Apicomplexa, is likely to have been obtained via lateral gene transfer from a prokaryote.
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Affiliation(s)
- John G Mina
- Department of Biosciences, Durham University, Durham DH1 3LE, United Kingdom
| | - Julie K Thye
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
| | - Amjed Q I Alqaisi
- Department of Biosciences, Durham University, Durham DH1 3LE, United Kingdom; Biology Department, College of Science, University of Baghdad, Baghdad 10071, Iraq
| | - Louise E Bird
- Oxford Protein Production Facility UK, Research Complex at Harwell, Rutherford Appleton Laboratory, Didcot OX11 0FA, United Kingdom
| | - Robert H Dods
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
| | | | - Jackie A Mosely
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
| | - Steven Pratt
- Department of Biosciences, Durham University, Durham DH1 3LE, United Kingdom
| | - Hosam Shams-Eldin
- Institut für Virologie, Zentrum für Hygiene und Infektionsbiologie, Philipps-Universität Marburg, 35043 Marburg, Germany
| | - Ralph T Schwarz
- Institut für Virologie, Zentrum für Hygiene und Infektionsbiologie, Philipps-Universität Marburg, 35043 Marburg, Germany
| | - Ehmke Pohl
- Department of Biosciences, Durham University, Durham DH1 3LE, United Kingdom; Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
| | - Paul W Denny
- Department of Biosciences, Durham University, Durham DH1 3LE, United Kingdom.
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12
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Morlon‐Guyot J, Pastore S, Berry L, Lebrun M, Daher W. Toxoplasma gondii
Vps11, a subunit of
HOPS
and
CORVET
tethering complexes, is essential for the biogenesis of secretory organelles. Cell Microbiol 2015; 17:1157-78. [DOI: 10.1111/cmi.12426] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2014] [Revised: 01/20/2015] [Accepted: 01/28/2015] [Indexed: 12/17/2022]
Affiliation(s)
- Juliette Morlon‐Guyot
- Dynamique des Interactions Membranaires Normales et Pathologiques, UMR5235 CNRS Université Montpellier Montpellier France
| | - Sandra Pastore
- Dynamique des Interactions Membranaires Normales et Pathologiques, UMR5235 CNRS Université Montpellier Montpellier France
| | - Laurence Berry
- Dynamique des Interactions Membranaires Normales et Pathologiques, UMR5235 CNRS Université Montpellier Montpellier France
| | - Maryse Lebrun
- Dynamique des Interactions Membranaires Normales et Pathologiques, UMR5235 CNRS Université Montpellier Montpellier France
| | - Wassim Daher
- Dynamique des Interactions Membranaires Normales et Pathologiques, UMR5235 CNRS Université Montpellier Montpellier France
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Toxoplasma gondii nucleus coding apicoplast protein ACP synthesis and trafficking in delayed death. Parasitol Res 2015; 114:1099-105. [PMID: 25563610 DOI: 10.1007/s00436-014-4281-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2014] [Accepted: 12/16/2014] [Indexed: 01/14/2023]
Abstract
This study aimed to explore Toxoplasma gondii nucleus coding apicoplast protein acyl carrier protein (ACP) synthesis and trafficking in delayed death. The recombinant T. gondii ACP was expressed by prokaryotic expression method, and anti-ACP polyclonal antibody was obtained from rabbit immune. T. gondii "delayed death" was induced by clindamycin (CLDM), and ACP transcription was determined by real-time PCR assay. The expression of ACP with transit type (t-ACP) and mature type (m-ACP) was determined by Western blotting with anti-ACP polyclonal antibody. The mutant-expressed ACP fused with green fluorescent protein (GFP) tag was constructed by pHX-ACP-GFP. The distribution of ACP in "delayed death" was observed by ACP-GFP fusion protein with a confocal microscope. T. gondii ACP transcription and t-ACP expression had no significant decrease in the early 4 h of "delayed death," but there has been a significant decrease in 6 h. The expression of m-ACP had a significant decrease in 4 h which occurred earlier than the t-ACP expression. The number of brightly dot green fluorescence in ACP-GFP mutant decreased with prolonged time. There was very little brightly dot green fluorescence in ACP-GFP mutant when treated with CLDM for 6 h. CLDM could suppress apicoplast proliferation and induce T. gondii "delayed death"; however, it could not directly suppress nucleus coding ACP transcription and expression. T. gondii lacking of apicoplast had a barrier of transit peptide cleavage and t-ACP could not be transformed into m-ACP. The reason for the decrease in ACP expression could be due to excessive t-ACP synthesis in tachyzoites resulting in a negative feedback for the ACP coding gene transcription.
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The role of clathrin in post-Golgi trafficking in Toxoplasma gondii. PLoS One 2013; 8:e77620. [PMID: 24147036 PMCID: PMC3795686 DOI: 10.1371/journal.pone.0077620] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2013] [Accepted: 09/13/2013] [Indexed: 11/19/2022] Open
Abstract
Apicomplexan parasites are single eukaryotic cells with a highly polarised secretory system that contains unique secretory organelles (micronemes and rhoptries) that are required for host cell invasion. In contrast, the role of the endosomal system is poorly understood in these parasites. With many typical endocytic factors missing, we speculated that endocytosis depends exclusively on a clathrin-mediated mechanism. Intriguingly, in Toxoplasma gondii we were only able to observe the endogenous clathrin heavy chain 1 (CHC1) at the Golgi, but not at the parasite surface. For the functional characterisation of Toxoplasma gondii CHC1 we generated parasite mutants conditionally expressing the dominant negative clathrin Hub fragment and demonstrate that CHC1 is essential for vesicle formation at the trans-Golgi network. Consequently, the functional ablation of CHC1 results in Golgi aberrations, a block in the biogenesis of the unique secretory microneme and rhoptry organelles, and of the pellicle. However, we found no morphological evidence for clathrin mediating endocytosis in these parasites and speculate that they remodelled their vesicular trafficking system to adapt to an intracellular lifestyle.
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Jackson AJ, Clucas C, Mamczur NJ, Ferguson DJ, Meissner M. Toxoplasma gondii Syntaxin 6 is required for vesicular transport between endosomal-like compartments and the Golgi complex. Traffic 2013; 14:1166-81. [PMID: 23962112 PMCID: PMC3963449 DOI: 10.1111/tra.12102] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2012] [Revised: 08/15/2013] [Accepted: 08/20/2013] [Indexed: 11/28/2022]
Abstract
Apicomplexans are obligate intracellular parasites that invade the host cell in an active process that relies on unique secretory organelles (micronemes, rhoptries and dense granules) localized at the apical tip of these highly polarized eukaryotes. In order for the contents of these specialized organelles to reach their final destination, these proteins are sorted post-Golgi and it has been speculated that they pass through endosomal-like compartments (ELCs), where they undergo maturation. Here, we characterize a Toxoplasma gondii homologue of Syntaxin 6 (TgStx6), a well-established marker for the early endosomes and trans Golgi network (TGN) in diverse eukaryotes. Indeed, TgStx6 appears to have a role in the retrograde transport between ELCs, the TGN and the Golgi, because overexpression of TgStx6 results in the development of abnormally shaped parasites with expanded ELCs, a fragmented Golgi and a defect in inner membrane complex maturation. Interestingly, other organelles such as the micronemes, rhoptries and the apicoplast are not affected, establishing the TGN as a major sorting compartment where several transport pathways intersect. It therefore appears that Toxoplasma has retained a plant-like secretory pathway.
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Affiliation(s)
- Allison J Jackson
- Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, The University of Glasgow, Glasgow, G12 8TA, UK
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16
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Kremer K, Kamin D, Rittweger E, Wilkes J, Flammer H, Mahler S, Heng J, Tonkin CJ, Langsley G, Hell SW, Carruthers VB, Ferguson DJP, Meissner M. An overexpression screen of Toxoplasma gondii Rab-GTPases reveals distinct transport routes to the micronemes. PLoS Pathog 2013; 9:e1003213. [PMID: 23505371 PMCID: PMC3591302 DOI: 10.1371/journal.ppat.1003213] [Citation(s) in RCA: 109] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Accepted: 01/10/2013] [Indexed: 12/20/2022] Open
Abstract
The basic organisation of the endomembrane system is conserved in all eukaryotes and comparative genome analyses provides compelling evidence that the endomembrane system of the last common eukaryotic ancestor (LCEA) is complex with many genes required for regulated traffic being present. Although apicomplexan parasites, causative agents of severe human and animal diseases, appear to have only a basic set of trafficking factors such as Rab-GTPases, they evolved unique secretory organelles (micronemes, rhoptries and dense granules) that are sequentially secreted during invasion of the host cell. In order to define the secretory pathway of apicomplexans, we performed an overexpression screen of Rabs in Toxoplasma gondii and identified Rab5A and Rab5C as important regulators of traffic to micronemes and rhoptries. Intriguingly, we found that not all microneme proteins traffic depends on functional Rab5A and Rab5C, indicating the existence of redundant microneme targeting pathways. Using two-colour super-resolution stimulated emission depletion (STED) we verified distinct localisations of independent microneme proteins and demonstrate that micronemal organelles are organised in distinct subsets or subcompartments. Our results suggest that apicomplexan parasites modify classical regulators of the endocytic system to carryout essential parasite-specific roles in the biogenesis of their unique secretory organelles. Eukaryotic cells evolved a highly complex endomembrane system, consisting of secretory and endocytic organelles. In the case of apicomplexan parasites unique secretory organelles have evolved that are essential for the invasion of the host cell. Surprisingly these protozoans show a paucity of trafficking factors, such as Rabs and it appears that they lost several factors involved in endocytosis. Here, we demonstrate that Rab5A and Rab5C, normally involved in endocytic uptake, actually regulate secretion in Toxoplasma gondii, since functional ablation of Rab5A or Rab5C results in aberrant transport of proteins to specialised secretory organelles called micronemes and rhoptries. Furthermore, we demonstrate that independent transport routes to micronemes exist indicating that apicomplexans have remodelled Rab5-mediated vesicular traffic into a secretory system that is essential for host cell invasion.
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Affiliation(s)
- Katrin Kremer
- Institute of Infection, Immunity and Inflammation, Wellcome Centre for Molecular Parasitology, Glasgow Biomedical Research Centre, University of Glasgow, Glasgow, United Kingdom
| | - Dirk Kamin
- Department of NanoBiophotonics, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Eva Rittweger
- German Cancer Research Center/BioQuant, Heidelberg, Germany
| | - Jonathan Wilkes
- Institute of Infection, Immunity and Inflammation, Wellcome Centre for Molecular Parasitology, Glasgow Biomedical Research Centre, University of Glasgow, Glasgow, United Kingdom
| | - Halley Flammer
- Department of Microbiology and Immunology, University of Michigan School of Medicine, Ann Arbor, Michigan, United States of America
| | - Sabine Mahler
- Parasitology, Department of Infectious Diseases, University of Heidelberg Medical School, Heidelberg, Germany
| | - Joanne Heng
- Institute of Infection, Immunity and Inflammation, Wellcome Centre for Molecular Parasitology, Glasgow Biomedical Research Centre, University of Glasgow, Glasgow, United Kingdom
| | | | - Gordon Langsley
- Laboratoire de Biologie Cellulaire Comparative des Apicomplexes, Institut Cochin, Inserm, U567, CNRS, UMR 8104, Faculté de Médecine Paris V – Hôpital Cochin, Paris, France
| | - Stefan W. Hell
- Department of NanoBiophotonics, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Vernon B. Carruthers
- Department of Microbiology and Immunology, University of Michigan School of Medicine, Ann Arbor, Michigan, United States of America
| | - David J. P. Ferguson
- Nuffield Department of Pathology, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
| | - Markus Meissner
- Institute of Infection, Immunity and Inflammation, Wellcome Centre for Molecular Parasitology, Glasgow Biomedical Research Centre, University of Glasgow, Glasgow, United Kingdom
- * E-mail:
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Xu G, Li S, Xie K, Zhang Q, Wang Y, Tang Y, Liu D, Hong Y, He C, Liu Y. Plant ERD2-like proteins function as endoplasmic reticulum luminal protein receptors and participate in programmed cell death during innate immunity. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2012; 72:57-69. [PMID: 22595145 DOI: 10.1111/j.1365-313x.2012.05053.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
The hypersensitive response (HR), a form of programmed cell death (PCD), is a tightly regulated innate immune response in plants that is hypothesized to restrict pathogen growth and disease development. Although considerable efforts have been made to understand HR PCD, it remains unknown whether the retrograde pathway from the Golgi to the endoplasmic reticulum (ER) is involved. Here we provide direct genetic evidence that two Nicotiana benthamiana homologs, ERD2a and ERD2b, function as ER luminal protein receptors and participate in HR PCD. Virus-induced gene silencing (VIGS) of ERD2a and/or ERD2b caused escape of ER-resident proteins from the ER, and resulted in plants that were more sensitive to ER stress. Silencing of ERD2b delayed HR PCD induced by the non-host pathogens Xanthomonas oryzae pv. oryzae and Pseudomonas syringae pv. tomato DC3000. However, both silencing of ERD2a and co-silencing of ERD2a and ERD2b exacerbated HR PCD. Individual and combined suppression of ERD2a and ERD2b exaggerated R gene-mediated cell death. Nevertheless, silencing of ERD2a and/or ERD2b had no detectable effects on bacterial growth. Furthermore, VIGS of several putative ligands of ERD2a/2b, including the ER quality control (ERQC) component genes BiP, CRT3 and UGGT, had different effects on HR PCD induced by different pathogens. This indicates that immunity-related cell death pathways are separate with respect to the genetic requirements for these ERQC components. These results suggest that ERD2a and ERD2b function as ER luminal protein receptors to ensure ERQC and alleviate ER stress, thus affecting HR PCD during the plant innate immune response.
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Affiliation(s)
- Guoyong Xu
- MOE Key Laboratory of Bioinformatics, School of Life Sciences, Tsinghua University, Beijing 100084, China
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18
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Agop-Nersesian C, Egarter S, Langsley G, Foth BJ, Ferguson DJP, Meissner M. Biogenesis of the inner membrane complex is dependent on vesicular transport by the alveolate specific GTPase Rab11B. PLoS Pathog 2010; 6:e1001029. [PMID: 20686666 PMCID: PMC2912401 DOI: 10.1371/journal.ppat.1001029] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2010] [Accepted: 07/02/2010] [Indexed: 01/09/2023] Open
Abstract
Apicomplexan parasites belong to a recently recognised group of protozoa referred to as Alveolata. These protists contain membranous sacs (alveoli) beneath the plasma membrane, termed the Inner Membrane Complex (IMC) in the case of Apicomplexa. During parasite replication the IMC is formed de novo within the mother cell in a process described as internal budding. We hypothesized that an alveolate specific factor is involved in the specific transport of vesicles from the Golgi to the IMC and identified the small GTPase Rab11B as an alveolate specific Rab-GTPase that localises to the growing end of the IMC during replication of Toxoplasma gondii. Conditional interference with Rab11B function leads to a profound defect in IMC biogenesis, indicating that Rab11B is required for the transport of Golgi derived vesicles to the nascent IMC of the daughter cell. Curiously, a block in IMC biogenesis did not affect formation of sub-pellicular microtubules, indicating that IMC biogenesis and formation of sub-pellicular microtubules is not mechanistically linked. We propose a model where Rab11B specifically transports vesicles derived from the Golgi to the immature IMC of the growing daughter parasites.
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Affiliation(s)
- Carolina Agop-Nersesian
- Department of Infectiology, Parasitology, University Hospital Heidelberg, Heidelberg, Germany
- * E-mail: (MM); (CAN)
| | - Saskia Egarter
- Division of Infection & Immunity and Wellcome Centre for Parasitology, Faculty of Biomedical and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Gordon Langsley
- Laboratoire de Biologie Cellulaire Comparative des Apicomplexes, Institut Cochin, Inserm, U567, CNRS, UMR 8104, Faculté de Médecine Paris V – Hôpital Cochin, Paris, France
| | - Bernardo J. Foth
- School of Biological Sciences, Nanyang Technological University, Singapore, Republic of Singapore
| | - David J. P. Ferguson
- Nuffield Department of Clinical Laboratory Science, Oxford University, Oxford, United Kingdom
| | - Markus Meissner
- Division of Infection & Immunity and Wellcome Centre for Parasitology, Faculty of Biomedical and Life Sciences, University of Glasgow, Glasgow, United Kingdom
- * E-mail: (MM); (CAN)
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Parsons M, Karnataki A, Derocher AE. Evolving insights into protein trafficking to the multiple compartments of the apicomplexan plastid. J Eukaryot Microbiol 2009; 56:214-20. [PMID: 19527348 DOI: 10.1111/j.1550-7408.2009.00405.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The apicoplast is a relict plastid found in many medically important apicomplexan parasites, such as Plasmodium and Toxoplasma. Phylogenetic analysis and the presence of four bounding membranes indicate that the apicoplast arose from a secondary endosymbiosis. Here we review what has been discovered about the complex journey proteins take to reach compartments of the apicoplast. The targeting sequences for luminal proteins are well-defined, but those routing proteins to other compartments are only beginning to be studied. Recent work suggests that the trafficking mechanisms involve a variety of molecules of different phylogenetic origins. We highlight some remaining questions regarding protein trafficking to this divergent organelle.
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Affiliation(s)
- Marilyn Parsons
- Seattle Biomedical Research Institute, Washington 98109, USA.
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20
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Breinich MS, Ferguson DJ, Foth BJ, van Dooren GG, Lebrun M, Quon DV, Striepen B, Bradley PJ, Frischknecht F, Carruthers VB, Meissner M. A dynamin is required for the biogenesis of secretory organelles in Toxoplasma gondii. Curr Biol 2009; 19:277-86. [PMID: 19217293 PMCID: PMC3941470 DOI: 10.1016/j.cub.2009.01.039] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2008] [Revised: 01/14/2009] [Accepted: 01/16/2009] [Indexed: 12/29/2022]
Abstract
BACKGROUND Apicomplexans contain only a core set of factors involved in vesicular traffic. Yet these obligate intracellular parasites evolved a set of unique secretory organelles (micronemes, rhoptries, and dense granules) that are required for invasion and modulation of the host cell. Apicomplexa replicate by budding from or within a single mother cell, and secretory organelles are synthesized de novo at the final stage of division. To date, the molecular basis for their biogenesis is unknown. RESULTS We demonstrate that the apicomplexan dynamin-related protein B (DrpB) belongs to an alveolate specific family of dynamins that is expanded in ciliates. DrpB accumulates in a cytoplasmic region close to the Golgi that breaks up during replication and reforms after assembly of the daughter cells. Conditional ablation of DrpB function results in mature daughter parasites that are devoid of micronemes and rhoptries. In the absence of these organelles, invasion-related secretory proteins are mistargeted to the constitutive secretory pathway. Mutant parasites are able to replicate but are unable to escape from or invade into host cells. CONCLUSIONS DrpB is the essential mechanoenzyme for the biogenesis of secretory organelles in Apicomplexa. We suggest that DrpB is required during replication to generate vesicles for the regulated secretory pathway that form the unique secretory organelles. Our study supports a role of an alveolate-specific dynamin that was required for the evolution of novel, secretory organelles. In the case of Apicomplexa, these organelles further evolved to enable a parasitic lifestyle.
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Affiliation(s)
- Manuela S. Breinich
- Hygiene Institute, Department of Parasitology, Heidelberg University School of Medicine, Heidelberg, Germany
| | - David J.P. Ferguson
- Nuffield Department of Pathology, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, United Kingdom
| | - Bernardo J. Foth
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551
| | - Giel G. van Dooren
- Center for Tropical and Emerging Global Diseases and Department of Cellular Biology, University of Georgia, Athens, 30602, GA, USA
| | - Maryse Lebrun
- INSERM, UMR 55235 CNRS, Université de Montpellier 2, CP 107, Place Eugène Bataillon, 34090 Montpellier, France
| | - Doris V. Quon
- Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles, Los Angeles CA 90095-1489 USA
| | - Boris Striepen
- Center for Tropical and Emerging Global Diseases and Department of Cellular Biology, University of Georgia, Athens, 30602, GA, USA
| | - Peter J. Bradley
- Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles, Los Angeles CA 90095-1489 USA
| | - Friedrich Frischknecht
- Hygiene Institute, Department of Parasitology, Heidelberg University School of Medicine, Heidelberg, Germany
| | - Vernon B. Carruthers
- Department of Microbiology and Immunology, University of Michigan School of Medicine, Ann Arbor, Michigan 48109, USA
| | - Markus Meissner
- Hygiene Institute, Department of Parasitology, Heidelberg University School of Medicine, Heidelberg, Germany
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21
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Walker ME, Hjort EE, Smith SS, Tripathi A, Hornick JE, Hinchcliffe EH, Archer W, Hager KM. Toxoplasma gondii actively remodels the microtubule network in host cells. Microbes Infect 2008; 10:1440-9. [PMID: 18983931 DOI: 10.1016/j.micinf.2008.08.014] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2008] [Revised: 08/11/2008] [Accepted: 08/12/2008] [Indexed: 11/15/2022]
Abstract
Toxoplasma gondii infection triggers host microtubule rearrangement and organelle recruitment around the parasite vacuole. Factors affecting initial stages of microtubule remodeling are unknown. To illuminate the mechanism, we tested the hypothesis that the parasite actively remodels host microtubules. Utilizing heat-killed parasites and time-lapse analysis, we determined microtubule rearrangement requires living parasites and is time dependent. We discovered a novel aster of microtubules (MTs) associates with the vacuole within 1h of infection. This aster lacks the concentrated foci of gamma (gamma)-tubulin normally associated with MT nucleation sites. Unexpectedly, vacuole enlargement does not correlate with an increase in MT staining around the vacuole. We conclude microtubule remodeling does not result from steric constraints. Using nocodazole washout studies, we demonstrate the vacuole nucleates host microtubule growth in-vivo via gamma-tubulin-associated sites. Moreover, superinfected host cells display multiple gamma-tubulin foci. Microtubule dynamics are critical for cell cycle control in uninfected cells. Using non-confluent monolayers, we show host cells commonly fail to finish cytokinesis resulting in larger, multinucleated cells. Our data suggest intimate interactions between T. gondii and host microtubules result in suppression of cell division and/or cause a mitotic defect, thus providing a larger space for parasite duplication.
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Affiliation(s)
- Margaret E Walker
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556-0369, USA
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22
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23
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Kessler H, Herm-Götz A, Hegge S, Rauch M, Soldati-Favre D, Frischknecht F, Meissner M. Microneme protein 8 – a new essential invasion factor inToxoplasma gondii. J Cell Sci 2008; 121:947-56. [PMID: 18319299 DOI: 10.1242/jcs.022350] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Apicomplexan parasites rely on sequential secretion of specialised secretory organelles for the invasion of the host cell. First, micronemes release their content upon contact with the host cell. Second, rhoptries are discharged, leading to the formation of a tight interaction (moving junction) with the host cell, through which the parasite invades. The functional characterisation of several micronemal proteins in Toxoplasma gondii suggests the occurrence of a stepwise process. Here, we show that the micronemal protein MIC8 of T. gondii is essential for the parasite to invade the host cell. When MIC8 is not present, a block in invasion is caused by the incapability of the parasite to form a moving junction with the host cell. We furthermore demonstrate that the cytosolic domain is crucial for the function of MIC8 and can not be functionally complemented by any other micronemal protein characterised so far, suggesting that MIC8 represents a novel, functionally distinct invasion factor in this apicomplexan parasite.
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Affiliation(s)
- Henning Kessler
- Hygieneinstitute, Department of Parasitology, University Hospital Heidelberg, Im Neuenheimer Feld 324, D-69120 Heidelberg, Germany
| | - Angelika Herm-Götz
- Hygieneinstitute, Department of Parasitology, University Hospital Heidelberg, Im Neuenheimer Feld 324, D-69120 Heidelberg, Germany
| | - Stephan Hegge
- Hygieneinstitute, Department of Parasitology, University Hospital Heidelberg, Im Neuenheimer Feld 324, D-69120 Heidelberg, Germany
| | - Manuel Rauch
- Hygieneinstitute, Department of Parasitology, University Hospital Heidelberg, Im Neuenheimer Feld 324, D-69120 Heidelberg, Germany
| | - Dominique Soldati-Favre
- Department of Microbiology and Molecular Medicine, University of Geneva, CMU, 1, rue Michel-Servet 1211, Geneva 4, Switzerland
| | - Friedrich Frischknecht
- Hygieneinstitute, Department of Parasitology, University Hospital Heidelberg, Im Neuenheimer Feld 324, D-69120 Heidelberg, Germany
| | - Markus Meissner
- Hygieneinstitute, Department of Parasitology, University Hospital Heidelberg, Im Neuenheimer Feld 324, D-69120 Heidelberg, Germany
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24
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Struck NS, Herrmann S, Schmuck-Barkmann I, de Souza Dias S, Haase S, Cabrera AL, Treeck M, Bruns C, Langer C, Cowman AF, Marti M, Spielmann T, Gilberger TW. Spatial dissection of the cis- and trans-Golgi compartments in the malaria parasite Plasmodium falciparum. Mol Microbiol 2008; 67:1320-30. [DOI: 10.1111/j.1365-2958.2008.06125.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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25
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Eggleston TL, Fitzpatrick E, Hager KM. Parasitology as a teaching tool: isolation of apicomplexan cysts from store-bought meat. CBE LIFE SCIENCES EDUCATION 2008; 7:184-192. [PMID: 18519609 PMCID: PMC2424304 DOI: 10.1187/cbe.07-08-0062] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2007] [Revised: 03/03/2008] [Accepted: 03/12/2008] [Indexed: 05/26/2023]
Affiliation(s)
- Tracy L. Eggleston
- *Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556-0369
- Center for Global Health and Infectious Disease, University of Notre Dame, Notre Dame, IN 46556-0369; and
| | | | - Kristin M. Hager
- *Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556-0369
- Center for Global Health and Infectious Disease, University of Notre Dame, Notre Dame, IN 46556-0369; and
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26
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Kats LM, Cooke BM, Coppel RL, Black CG. Protein Trafficking to Apical Organelles of Malaria Parasites - Building an Invasion Machine. Traffic 2007; 9:176-86. [PMID: 18047549 DOI: 10.1111/j.1600-0854.2007.00681.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Lev M Kats
- NHMRC Program in Malaria, Department of Microbiology, Monash University, Victoria 3800, Australia
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27
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Abstract
Apicomplexans are pathogens responsible for malaria, toxoplasmosis, and crytposporidiosis in humans, and a wide range of livestock diseases. These unicellular eukaryotes are stealthy invaders, sheltering from the immune response in the cells of their hosts, while at the same time tapping into these cells as source of nutrients. The complexity and beauty of the structures formed during their intracellular development have made apicomplexans the darling of electron microscopists. Dramatic technological progress over the last decade has transformed apicomplexans into respectable genetic model organisms. Extensive genomic resources are now available for many apicomplexan species. At the same time, parasite transfection has enabled researchers to test the function of specific genes through reverse and forward genetic approaches with increasing sophistication. Transfection also introduced the use of fluorescent reporters, opening the field to dynamic real time microscopic observation. Parasite cell biologists have used these tools to take a fresh look at a classic problem: how do apicomplexans build the perfect invasion machine, the zoite, and how is this process fine-tuned to fit the specific niche of each pathogen in this ancient and very diverse group? This work has unearthed a treasure trove of novel structures and mechanisms that are the focus of this review.
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Affiliation(s)
- Boris Striepen
- Center for Tropical and Emerging Global Diseases and the Department of Cellular Biology, University of Georgia, Athens, Georgia, United States of America.
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28
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Moran JM, Smith SS, Hager KM. Toxoplasma gondii possesses a receptor for activated C kinase ortholog. Biochem Biophys Res Commun 2007; 363:680-6. [PMID: 17900535 DOI: 10.1016/j.bbrc.2007.09.034] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2007] [Accepted: 09/10/2007] [Indexed: 11/17/2022]
Abstract
Receptor for activated C kinase 1 (RACK1) has been implicated in multiple protein-protein interactions including functioning as a scaffolding protein for signaling molecules. We report the cloning and cellular localization of a RACK1 ortholog (TgRACK1) in the opportunistic pathogen Toxoplasma gondii. The full-length transcript possesses a predicted ORF of 966 bp and codes for a protein of approximately 35 kDa molecular weight. Molecular analysis of TgRACK1 reveals the presence of seven WD40 repeat motifs. TgRACK1 was tagged with a FLAG epitope and stably expressed in RH parasites. FLAG-TgRACK1 localizes to the parasite cytoplasm and nucleus. Immunoprecipitation (IP) of FLAG-TgRACK1 from highly purified extracellular parasites followed by immunoblot analysis reveals an interaction between TgbetaCOP and FLAG-TgRACK1. This is the first demonstration of an interaction between a betaCOP subunit and the RACK1 protein. This result is of interest given that a signaling event precedes protein secretion and parasite invasion.
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Affiliation(s)
- Jennifer M Moran
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556-0369, USA
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Parsons M, Karnataki A, Feagin JE, DeRocher A. Protein trafficking to the apicoplast: deciphering the apicomplexan solution to secondary endosymbiosis. EUKARYOTIC CELL 2007; 6:1081-8. [PMID: 17513565 PMCID: PMC1951102 DOI: 10.1128/ec.00102-07] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Marilyn Parsons
- Seattle Biomedical Research Institute, 307 Westlake Ave. North, Seattle, WA 98109, USA.
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