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Tang L, Sabi MM, Fu M, Guan J, Wang Y, Xia T, Zheng K, Qu H, Han B. Host cell manipulation by microsporidia secreted effectors: Insights into intracellular pathogenesis. J Eukaryot Microbiol 2024:e13029. [PMID: 39030770 DOI: 10.1111/jeu.13029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2024] [Revised: 03/29/2024] [Accepted: 03/29/2024] [Indexed: 07/22/2024]
Abstract
Microsporidia are prolific producers of effector molecules, encompassing both proteins and nonproteinaceous effectors, such as toxins, small RNAs, and small peptides. These secreted effectors play a pivotal role in the pathogenicity of microsporidia, enabling them to subvert the host's innate immunity and co-opt metabolic pathways to fuel their own growth and proliferation. However, the genomes of microsporidia, despite falling within the size range of bacteria, exhibit significant reductions in both structural and physiological features, thereby affecting the repertoire of secretory effectors to varying extents. This review focuses on recent advances in understanding how microsporidia modulate host cells through the secretion of effectors, highlighting current challenges and proposed solutions in deciphering the complexities of microsporidial secretory effectors.
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Affiliation(s)
- Liyuan Tang
- Department of Pathogenic Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Ji'nan, Shandong, China
| | - Musa Makongoro Sabi
- Department of Pathogenic Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Ji'nan, Shandong, China
| | - Ming Fu
- Department of Pathogenic Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Ji'nan, Shandong, China
| | - Jingyu Guan
- Department of Pathogenic Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Ji'nan, Shandong, China
| | - Yongliang Wang
- Department of Pathogenic Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Ji'nan, Shandong, China
| | - Tian Xia
- Department of Pathogenic Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Ji'nan, Shandong, China
| | - Kai Zheng
- Department of Pathogenic Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Ji'nan, Shandong, China
| | - Hongnan Qu
- Department of Pathogenic Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Ji'nan, Shandong, China
- Shenzhen Research Institute, Shandong University, Shenzhen, Guangdong, China
| | - Bing Han
- Department of Pathogenic Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Ji'nan, Shandong, China
- Shenzhen Research Institute, Shandong University, Shenzhen, Guangdong, China
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2
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Giuliano CJ, Wei KJ, Harling FM, Waldman BS, Farringer MA, Boydston EA, Lan TCT, Thomas RW, Herneisen AL, Sanderlin AG, Coppens I, Dvorin JD, Lourido S. CRISPR-based functional profiling of the Toxoplasma gondii genome during acute murine infection. Nat Microbiol 2024:10.1038/s41564-024-01754-2. [PMID: 38977907 DOI: 10.1038/s41564-024-01754-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2024] [Accepted: 06/07/2024] [Indexed: 07/10/2024]
Abstract
Examining host-pathogen interactions in animals can capture aspects of infection that are obscured in cell culture. Using CRISPR-based screens, we functionally profile the entire genome of the apicomplexan parasite Toxoplasma gondii during murine infection. Barcoded gRNAs enabled bottleneck detection and mapping of population structures within parasite lineages. Over 300 genes with previously unknown roles in infection were found to modulate parasite fitness in mice. Candidates span multiple axes of host-parasite interaction. Rhoptry Apical Surface Protein 1 was characterized as a mediator of host-cell tropism that facilitates repeated invasion attempts. GTP cyclohydrolase I was also required for fitness in mice and druggable through a repurposed compound, 2,4-diamino-6-hydroxypyrimidine. This compound synergized with pyrimethamine against T. gondii and malaria-causing Plasmodium falciparum parasites. This work represents a complete survey of an apicomplexan genome during infection of an animal host and points to novel interfaces of host-parasite interaction.
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Affiliation(s)
| | - Kenneth J Wei
- Whitehead Institute, Cambridge, MA, USA
- Biology Department, MIT, Cambridge, MA, USA
| | | | - Benjamin S Waldman
- Whitehead Institute, Cambridge, MA, USA
- Biology Department, MIT, Cambridge, MA, USA
| | - Madeline A Farringer
- Division of Infectious Diseases, Boston Children's Hospital, Boston, MA, USA
- Biological Sciences in Public Health, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | | | | | - Raina W Thomas
- Whitehead Institute, Cambridge, MA, USA
- Biology Department, MIT, Cambridge, MA, USA
| | - Alice L Herneisen
- Whitehead Institute, Cambridge, MA, USA
- Biology Department, MIT, Cambridge, MA, USA
| | | | - Isabelle Coppens
- Department of Molecular Microbiology and Immunology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD, USA
| | - Jeffrey D Dvorin
- Division of Infectious Diseases, Boston Children's Hospital, Boston, MA, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA
| | - Sebastian Lourido
- Whitehead Institute, Cambridge, MA, USA.
- Biology Department, MIT, Cambridge, MA, USA.
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3
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Zheng XN, Li TT, Elsheikha HM, Wang M, Sun LX, Wu XJ, Fu BQ, Zhu XQ, Wang JL. GRA47 is important for the morphology and permeability of the parasitophorous vacuole in Toxoplasma gondii. Int J Parasitol 2024:S0020-7519(24)00135-8. [PMID: 38936501 DOI: 10.1016/j.ijpara.2024.06.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Revised: 05/13/2024] [Accepted: 06/20/2024] [Indexed: 06/29/2024]
Abstract
Establishing an intact intracellular parasitophorous vacuole (PV) that enables efficient nutrient uptake and protein trafficking is essential for the survival and proliferation of Toxoplasma gondii. Although the PV membrane (PVM)-localized dense granule protein 17 (GRA17) and GRA23 mediate the permeability of the PVM to small molecules, including nutrient uptake and excretion of metabolic by-products, the molecular mechanism by which T. gondii acquires nutrients remains unclear. In this study, we showed that the secreted protein GRA47 contributed to normal PV morphology, PVM permeability to small molecules, growth, and virulence in T. gondii. Co-immunoprecipitation analysis demonstrated potential interaction of GRA47 with GRA72, and the loss of GRA72 affected PV morphology, parasite growth and infectivity. To investigate the biological relationship among GRA47, GRA72, GRA17 and GRA23, attempts were made to construct strains with double gene deletion and overexpressing strains. Only Δgra23Δgra72 was successfully constructed. This strain exhibited a significant increase in the proportion of aberrant PVs compared with the Δgra23 strain. Overexpressing one of the three related GRAs partially rescued PVs with aberrant morphology in Δgra47, Δgra72 and Δgra17, while the expression of the Plasmodium falciparum PVM protein PfExp2, an ortholog of GRA17 and GRA23, fully rescued the PV morphological defect in all three Δgra strains. These results suggest that these GRA proteins may not be functionally redundant but rather work in different ways to regulate nutrient acquisition. These findings highlight the versatility of the nutrient uptake mechanisms in T. gondii, which may contribute to the parasite's remarkable ability to grow in different cellular niches in a very broad range of hosts.
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Affiliation(s)
- Xiao-Nan Zheng
- State Key Laboratory for Animal Disease Control and Prevention, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province 730046, People's Republic of China; Laboratory of Parasitic Diseases, College of Veterinary Medicine, Shanxi Agricultural University, Taigu, Shanxi Province 030801, People's Republic of China
| | - Ting-Ting Li
- State Key Laboratory for Animal Disease Control and Prevention, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province 730046, People's Republic of China; Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu, Sichuan Province 610213, People's Republic of China
| | - Hany M Elsheikha
- Faculty of Medicine and Health Sciences, School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington Campus, Loughborough, LE12 5RD, UK
| | - Meng Wang
- State Key Laboratory for Animal Disease Control and Prevention, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province 730046, People's Republic of China; Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu, Sichuan Province 610213, People's Republic of China
| | - Li-Xiu Sun
- State Key Laboratory for Animal Disease Control and Prevention, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province 730046, People's Republic of China; Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu, Sichuan Province 610213, People's Republic of China
| | - Xiao-Jing Wu
- State Key Laboratory for Animal Disease Control and Prevention, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province 730046, People's Republic of China; Laboratory of Parasitic Diseases, College of Veterinary Medicine, Shanxi Agricultural University, Taigu, Shanxi Province 030801, People's Republic of China
| | - Bao-Quan Fu
- State Key Laboratory for Animal Disease Control and Prevention, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province 730046, People's Republic of China; Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu, Sichuan Province 610213, People's Republic of China
| | - Xing-Quan Zhu
- Laboratory of Parasitic Diseases, College of Veterinary Medicine, Shanxi Agricultural University, Taigu, Shanxi Province 030801, People's Republic of China.
| | - Jin-Lei Wang
- State Key Laboratory for Animal Disease Control and Prevention, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province 730046, People's Republic of China; Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu, Sichuan Province 610213, People's Republic of China.
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4
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Nayeri T, Sarvi S, Daryani A. Effective factors in the pathogenesis of Toxoplasmagondii. Heliyon 2024; 10:e31558. [PMID: 38818168 PMCID: PMC11137575 DOI: 10.1016/j.heliyon.2024.e31558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 05/11/2024] [Accepted: 05/17/2024] [Indexed: 06/01/2024] Open
Abstract
Toxoplasma gondii (T. gondii) is a cosmopolitan protozoan parasite in humans and animals. It infects about 30 % of the human population worldwide and causes potentially fatal diseases in immunocompromised hosts and neonates. For this study, five English-language databases (ScienceDirect, ProQuest, Web of Science, PubMed, and Scopus) and the internet search engine Google Scholar were searched. This review was accomplished to draw a global perspective of what is known about the pathogenesis of T. gondii and various factors affecting it. Virulence and immune responses can influence the mechanisms of parasite pathogenesis and these factors are in turn influenced by other factors. In addition to the host's genetic background, the type of Toxoplasma strain, the routes of transmission of infection, the number of passages, and different phases of parasite life affect virulence. The identification of virulence factors of the parasite could provide promising insights into the pathogenesis of this parasite. The results of this study can be an incentive to conduct more intensive research to design and develop new anti-Toxoplasma agents (drugs and vaccines) to treat or prevent this infection. In addition, further studies are needed to better understand the key agents in the pathogenesis of T. gondii.
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Affiliation(s)
- Tooran Nayeri
- Infectious and Tropical Diseases Research Center, Dezful University of Medical Sciences, Dezful, Iran
- Student Research Committee, Mazandaran University of Medical Sciences, Sari, Iran
| | - Shahabeddin Sarvi
- Department of Parasitology, School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
| | - Ahmad Daryani
- Department of Parasitology, School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
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Carruthers VB, Dou Z. Deciphering protein prenylation in endocytic trafficking in Toxoplasma gondii. mBio 2024; 15:e0028324. [PMID: 38407123 PMCID: PMC11005354 DOI: 10.1128/mbio.00283-24] [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] [Indexed: 02/27/2024] Open
Abstract
Toxoplasma gondii is a widespread intracellular protozoan pathogen infecting virtually all warm-blooded animals. This parasite acquires host-derived resources to support its replication inside a membrane-bound parasitophorous vacuole within infected host cells. Previous research has discovered that Toxoplasma actively endocytoses host proteins and transports them to a lysosome-equivalent structure for digestion. However, few molecular determinants required for trafficking of host-derived material within the parasite were known. A recent study (Q.-Q. Wang, M. Sun, T. Tang, D.-H. Lai, et al., mBio 14:e01309-23, 2023, https://doi.org/10.1128/mbio.01309-23) identified a critical role for membrane anchoring of proteins via prenylation in the trafficking of endocytosed host proteins by Toxoplasma, including an essential Toxoplasma ortholog of Rab1B. The authors also found that TgRab1 is crucial for protein trafficking of the rhoptry secretory organelles, indicating a dual role in endocytic and exocytic protein trafficking. This study sets the stage for further dissecting endomembrane trafficking in Toxoplasma, along with potentially exploiting protein prenylation as a target for therapeutic development.
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Affiliation(s)
- Vern B. Carruthers
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Zhicheng Dou
- Department of Biological Sciences, Clemson University, Clemson, South Carolina, USA
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Zhang ZW, Wang M, Sun LX, Elsheikha HM, Lei CL, Wang JL, Fu BQ, Luo JX, Zhu XQ, Li TT. Trx4, a novel thioredoxin protein, is important for Toxoplasma gondii fitness. Parasit Vectors 2024; 17:178. [PMID: 38576040 PMCID: PMC10996207 DOI: 10.1186/s13071-024-06259-9] [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: 02/26/2024] [Accepted: 03/21/2024] [Indexed: 04/06/2024] Open
Abstract
BACKGROUND To successfully replicate within the host cell, Toxoplasma gondii employs several mechanisms to overcome the host cell defenses and mitigate the harmful effects of the free radicals resulting from its own metabolic processes using effectors such as thioredoxin proteins. In this study, we characterize the location and functions of a newly identified thioredoxin in T. gondii, which was named Trx4. METHODS We characterized the functional role of Trx4 in T. gondii Type I RH and Type II Pru strains by gene knockout and studied its subcellular localization by endogenous protein HA tagging using CRISPR-Cas9 gene editing. The enzyme-catalyzed proximity labeling technique, the TurboID system, was employed to identify the proteins in proximity to Trx4. RESULTS Trx4 was identified as a dense granule protein of T. gondii predominantly expressed in the parasitophorous vacuole (PV) and was partially co-localized with GRA1 and GRA5. Functional analysis showed that deletion of trx4 markedly influenced the parasite lytic cycle, resulting in impaired host cell invasion capacity in both RH and Pru strains. Mutation of Trx domains in Trx4 in RH strain revealed that two Trx domains were important for the parasite invasion. By utilizing the TurboID system to biotinylate proteins in proximity to Trx4, we identified a substantial number of proteins, some of which are novel, and others are previously characterized, predominantly distributed in the dense granules. In addition, we uncovered three novel proteins co-localized with Trx4. Intriguingly, deletion of trx4 did not affect the localization of these three proteins. Finally, a virulence assay demonstrated that knockout of trx4 resulted in a significant attenuation of virulence and a significant reduction in brain cyst loads in mice. CONCLUSIONS Trx4 plays an important role in T. gondii invasion and virulence in Type I RH strain and Type II Pru strain. Combining the TurboID system with CRISPR-Cas9 technique revealed many PV-localized proximity proteins associated with Trx4. These findings suggest a versatile role of Trx4 in mediating the processes that occur in this distinctive intracellular membrane-bound vacuolar compartment.
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Affiliation(s)
- Zhi-Wei Zhang
- State Key Laboratory for Animal Disease Control and Prevention, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, 730046, People's Republic of China
| | - Meng Wang
- State Key Laboratory for Animal Disease Control and Prevention, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, 730046, People's Republic of China
| | - Li-Xiu Sun
- State Key Laboratory for Animal Disease Control and Prevention, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, 730046, People's Republic of China
| | - Hany M Elsheikha
- Faculty of Medicine and Health Sciences, School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington Campus, Loughborough, LE12 5RD, UK
| | - Cheng-Lin Lei
- State Key Laboratory for Animal Disease Control and Prevention, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, 730046, People's Republic of China
| | - Jin-Lei Wang
- State Key Laboratory for Animal Disease Control and Prevention, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, 730046, People's Republic of China
- Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu, Sichuan Province, 610213, People's Republic of China
| | - Bao-Quan Fu
- State Key Laboratory for Animal Disease Control and Prevention, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, 730046, People's Republic of China
- Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu, Sichuan Province, 610213, People's Republic of China
| | - Jian-Xun Luo
- State Key Laboratory for Animal Disease Control and Prevention, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, 730046, People's Republic of China
| | - Xing-Quan Zhu
- Laboratory of Parasitic Diseases, College of Veterinary Medicine, Shanxi Agricultural University, Taigu, Shanxi Province, 030801, People's Republic of China.
| | - Ting-Ting Li
- State Key Laboratory for Animal Disease Control and Prevention, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, 730046, People's Republic of China.
- Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu, Sichuan Province, 610213, People's Republic of China.
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7
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Bitew MA, Gaete PS, Swale C, Maru P, Contreras JE, Saeij JPJ. Two Toxoplasma gondii putative pore-forming proteins, GRA47 and GRA72, influence small molecule permeability of the parasitophorous vacuole. mBio 2024; 15:e0308123. [PMID: 38380952 PMCID: PMC10936148 DOI: 10.1128/mbio.03081-23] [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: 11/13/2023] [Accepted: 02/01/2024] [Indexed: 02/22/2024] Open
Abstract
Toxoplasma gondii, a medically important intracellular parasite, uses GRA proteins secreted from dense granule organelles to mediate nutrient flux across the parasitophorous vacuole membrane (PVM). GRA17 and GRA23 are known pore-forming proteins on the PVM involved in this process, but the roles of additional proteins have remained largely uncharacterized. We recently identified GRA72 as synthetically lethal with GRA17. Deleting GRA72 produced similar phenotypes to Δgra17 parasites, and computational predictions suggested it forms a pore. To understand how GRA72 functions, we performed immunoprecipitation experiments and identified GRA47 as an interactor of GRA72. Deletion of GRA47 resulted in an aberrant "bubble vacuole" morphology with reduced small molecule permeability, mirroring the phenotype observed in GRA17 and GRA72 knockouts. Structural predictions indicated that GRA47 and GRA72 form heptameric and hexameric pores, respectively, with conserved histidine residues lining the pore. Mutational analysis highlighted the critical role of these histidines for protein functionality. Validation through electrophysiology confirmed alterations in membrane conductance, corroborating their pore-forming capabilities. Furthermore, Δgra47 parasites and parasites expressing GRA47 with a histidine mutation had reduced in vitro proliferation and attenuated virulence in mice. Our findings show the important roles of GRA47 and GRA72 in regulating PVM permeability, thereby expanding the repertoire of potential therapeutic targets against Toxoplasma infections. IMPORTANCE Toxoplasma gondii is a parasite that poses significant health risks to those with impaired immunity. It replicates inside host cells shielded by the PVM, which controls nutrient and waste exchange with the host. GRA72, previously identified as essential in the absence of the GRA17 nutrient channel, is implicated in forming an alternative nutrient channel. Here we found that GRA47 associates with GRA72 and is also important for the PVM's permeability to small molecules. Removal of GRA47 leads to distorted vacuoles and impairs small molecule transport across the PVM, resembling the effects of GRA17 and GRA72 deletions. Structural models suggest GRA47 and GRA72 form distinct pore structures, with a pore-lining histidine critical to their function. Toxoplasma strains lacking GRA47 or those with a histidine mutation have impaired growth and reduced virulence in mice, highlighting these proteins as potential targets for new treatments against toxoplasmosis.
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Affiliation(s)
- Mebratu A. Bitew
- Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California, Davis, California, USA
| | - Pablo S. Gaete
- Department of Physiology and Membrane Biology, University of California, Davis, California, USA
| | - Christopher Swale
- Team Host-Pathogen Interactions and Immunity to Infection, Institute for Advanced Biosciences (IAB), INSERM U1209, CNRS UMR5309, University Grenoble Alpes, Grenoble, France
| | - Parag Maru
- Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California, Davis, California, USA
| | - Jorge E. Contreras
- Department of Physiology and Membrane Biology, University of California, Davis, California, USA
| | - Jeroen P. J. Saeij
- Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California, Davis, California, USA
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Wang Y, Hollingsworth LR, Sangaré LO, Paredes-Santos TC, Krishnamurthy S, Penn BH, Wu H, Saeij JPJ. Host E3 ubiquitin ligase ITCH mediates Toxoplasma gondii effector GRA35-triggered NLRP1 inflammasome activation and cell-autonomous immunity. mBio 2024; 15:e0330223. [PMID: 38376248 PMCID: PMC10936166 DOI: 10.1128/mbio.03302-23] [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: 12/11/2023] [Accepted: 01/31/2024] [Indexed: 02/21/2024] Open
Abstract
Toxoplasma gondii is an intracellular parasite that can activate the NLRP1 inflammasome leading to macrophage pyroptosis in Lewis rats, but the underlying mechanism is not well understood. In this study, we performed a genome-wide CRISPR screen and identified the dense granule proteins GRA35, GRA42, and GRA43 as the Toxoplasma effectors mediating cell death in Lewis rat macrophages. GRA35 localizes on the parasitophorous vacuole membrane, where it interacts with the host E3 ubiquitin ligase ITCH. Inhibition of proteasome activity or ITCH knockout prevented pyroptosis in Toxoplasma-infected Lewis rat macrophages, consistent with the "NLRP1 functional degradation model." However, there was no evidence that ITCH directly ubiquitinates or interacts with rat NLRP1. We also found that GRA35-ITCH interaction affected Toxoplasma fitness in IFNγ-activated human fibroblasts, likely due to ITCH's role in recruiting ubiquitin and the parasite-restriction factor RNF213 to the parasitophorous vacuole membrane. These findings identify a new role of host E3 ubiquitin ligase ITCH in mediating effector-triggered immunity, a critical concept that involves recognizing intracellular pathogens and initiating host innate immune responses.IMPORTANCEEffector-triggered immunity represents an innate immune defense mechanism that plays a crucial role in sensing and controlling intracellular pathogen infection. The NLRP1 inflammasome in the Lewis rats can detect Toxoplasma infection, which triggers proptosis in infected macrophages and eliminates the parasite's replication niche. The work reported here revealed that host E3 ubiquitin ligase ITCH is able to recognize and interact with Toxoplasma effector protein GRA35 localized on the parasite-host interface, leading to NLRP1 inflammasome activation in Lewis rat macrophages. Furthermore, ITCH-GRA35 interaction contributes to the restriction of Toxoplasma in human fibroblasts stimulated by IFNγ. Thus, this research provides valuable insights into understanding pathogen recognition and restriction mediated by host E3 ubiquitin ligase.
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Affiliation(s)
- Yifan Wang
- Department of Pathology, Microbiology & Immunology, School of Veterinary Medicine, University of California, Davis, California, USA
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - L. Robert Hollingsworth
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts, USA
- Program in Cellular and Molecular Medicine, Boston Children’s Hospital, Boston, Massachusetts, USA
- Program in Biological and Biomedical Sciences, Harvard Medical School, Boston, Massachusetts, USA
| | - Lamba Omar Sangaré
- Department of Pathology, Microbiology & Immunology, School of Veterinary Medicine, University of California, Davis, California, USA
- Department of Biology, Texas A&M University, College Station, Texas, USA
| | - Tatiana C. Paredes-Santos
- Department of Pathology, Microbiology & Immunology, School of Veterinary Medicine, University of California, Davis, California, USA
| | - Shruthi Krishnamurthy
- Department of Pathology, Microbiology & Immunology, School of Veterinary Medicine, University of California, Davis, California, USA
| | - Bennett H. Penn
- Department of Internal Medicine, Division of Infectious Diseases, UC Davis Health, Sacramento, California, USA
- Department of Medical Microbiology and Immunology, University of California, Davis, California, USA
| | - Hao Wu
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts, USA
- Program in Cellular and Molecular Medicine, Boston Children’s Hospital, Boston, Massachusetts, USA
- Program in Biological and Biomedical Sciences, Harvard Medical School, Boston, Massachusetts, USA
| | - Jeroen P. J. Saeij
- Department of Pathology, Microbiology & Immunology, School of Veterinary Medicine, University of California, Davis, California, USA
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9
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Desai SA. Novel Ion Channel Genes in Malaria Parasites. Genes (Basel) 2024; 15:296. [PMID: 38540355 PMCID: PMC10970509 DOI: 10.3390/genes15030296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Revised: 02/19/2024] [Accepted: 02/23/2024] [Indexed: 06/14/2024] Open
Abstract
Ion channels serve many cellular functions including ion homeostasis, volume regulation, signaling, nutrient acquisition, and developmental progression. Although the complex life cycles of malaria parasites necessitate ion and solute flux across membranes, the whole-genome sequencing of the human pathogen Plasmodium falciparum revealed remarkably few orthologs of known ion channel genes. Contrasting with this, biochemical studies have implicated the channel-mediated flux of ions and nutritive solutes across several membranes in infected erythrocytes. Here, I review advances in the cellular and molecular biology of ion channels in malaria parasites. These studies have implicated novel parasite genes in the formation of at least two ion channels, with additional ion channels likely present in various membranes and parasite stages. Computational approaches that rely on homology to known channel genes from higher organisms will not be very helpful in identifying the molecular determinants of these activities. Given their unusual properties, novel molecular and structural features, and essential roles in pathogen survival and development, parasite channels should be promising targets for therapy development.
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Affiliation(s)
- Sanjay A Desai
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
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10
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Zheng XN, Sun LX, Elsheikha HM, Li TT, Gao J, Wu XJ, Zhang ZW, Wang M, Fu BQ, Zhu XQ, Wang JL. A newly characterized dense granule protein (GRA76) is important for the growth and virulence of Toxoplasma gondii. Int J Parasitol 2024; 54:109-121. [PMID: 37832712 DOI: 10.1016/j.ijpara.2023.09.001] [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: 07/26/2023] [Revised: 08/30/2023] [Accepted: 09/03/2023] [Indexed: 10/15/2023]
Abstract
Pathogenicity of the zoonotic pathogen Toxoplasma gondii largely depends on the secretion of effector proteins into the extracellular milieu and host cell cytosol, including the dense granule proteins (GRAs). The protein-encoding gene TGME49_299780 was previously identified as a contributor to parasite fitness. However, its involvement in parasite growth, virulence and infectivity in vitro and in vivo remains unknown. Here, we comprehensively examined the role of this new protein, termed GRA76, in parasite pathogenicity. Subcellular localization revealed high expression of GRA76 in tachyzoites inside the parasitophorous vacuole (PV). However, its expression was significantly decreased in bradyzoites. A CRISPR-Cas9 approach was used to knock out the gra76 gene in the T. gondii type I RH strain and type II Pru strain. The in vitro plaque assays and intracellular replication showed the involvement of GRA76 in replication of RH and Pru strains. Deletion of the gra76 gene significantly decreased parasite virulence, and reduced the brain cyst burden in mice. Using RNA sequencing, we detected a significant increase in the expression of bradyzoite-associated genes such as BAG1 and LDH2 in the PruΔgra76 strain compared with the wild-type Pru strain. Using an in vitro bradyzoite differentiation assay, we showed that loss of GRA76 significantly increased the propensity for parasites to form bradyzoites. Immunization with PruΔgra76 conferred partial protection against acute and chronic infection in mice. These findings show the important role of GRA76 in the pathogenesis of T. gondii and highlight the potential of PruΔgra76 as a candidate for a live-attenuated vaccine.
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Affiliation(s)
- Xiao-Nan Zheng
- State Key Laboratory for Animal Disease Control and Prevention, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province 730046, People's Republic of China; Laboratory of Parasitic Diseases, College of Veterinary Medicine, Shanxi Agricultural University, Taigu, Shanxi Province 030801, People's Republic of China
| | - Li-Xiu Sun
- State Key Laboratory for Animal Disease Control and Prevention, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province 730046, People's Republic of China; Research Center for Parasites & Vectors, College of Veterinary Medicine, Hunan Agricultural University, Changsha, Hunan Province 410128, People's Republic of China
| | - Hany M Elsheikha
- Faculty of Medicine and Health Sciences, School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington Campus, Loughborough LE12 5RD, UK
| | - Ting-Ting Li
- State Key Laboratory for Animal Disease Control and Prevention, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province 730046, People's Republic of China; Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu, Sichuan Province 610213, People's Republic of China
| | - Jin Gao
- State Key Laboratory for Animal Disease Control and Prevention, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province 730046, People's Republic of China; Laboratory of Parasitic Diseases, College of Veterinary Medicine, Shanxi Agricultural University, Taigu, Shanxi Province 030801, People's Republic of China
| | - Xiao-Jing Wu
- State Key Laboratory for Animal Disease Control and Prevention, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province 730046, People's Republic of China; Laboratory of Parasitic Diseases, College of Veterinary Medicine, Shanxi Agricultural University, Taigu, Shanxi Province 030801, People's Republic of China
| | - Zhi-Wei Zhang
- State Key Laboratory for Animal Disease Control and Prevention, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province 730046, People's Republic of China
| | - Meng Wang
- State Key Laboratory for Animal Disease Control and Prevention, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province 730046, People's Republic of China; Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu, Sichuan Province 610213, People's Republic of China
| | - Bao-Quan Fu
- State Key Laboratory for Animal Disease Control and Prevention, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province 730046, People's Republic of China; Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu, Sichuan Province 610213, People's Republic of China
| | - Xing-Quan Zhu
- Laboratory of Parasitic Diseases, College of Veterinary Medicine, Shanxi Agricultural University, Taigu, Shanxi Province 030801, People's Republic of China.
| | - Jin-Lei Wang
- State Key Laboratory for Animal Disease Control and Prevention, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province 730046, People's Republic of China; Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu, Sichuan Province 610213, People's Republic of China.
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11
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Houngue R, Sangaré LO, Alayi TD, Dieng A, Bitard-Feildel T, Boulogne C, Slomianny C, Atindehou CM, Fanou LA, Hathout Y, Callebaut I, Tomavo S. Toxoplasma membrane inositol phospholipid binding protein TgREMIND is essential for secretory organelle function and host infection. Cell Rep 2024; 43:113601. [PMID: 38157297 DOI: 10.1016/j.celrep.2023.113601] [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: 03/20/2023] [Revised: 10/25/2023] [Accepted: 12/04/2023] [Indexed: 01/03/2024] Open
Abstract
Apicomplexan parasites possess specialized secretory organelles called rhoptries, micronemes, and dense granules that play a vital role in host infection. In this study, we demonstrate that TgREMIND, a protein found in Toxoplasma gondii, is necessary for the biogenesis of rhoptries and dense granules. TgREMIND contains a Fes-CIP4 homology-Bin/Amphiphysin/Rvs (F-BAR) domain, which binds to membrane phospholipids, as well as a novel uncharacterized domain that we have named REMIND (regulator of membrane-interacting domain). Both the F-BAR domain and the REMIND are crucial for TgREMIND functions. When TgREMIND is depleted, there is a significant decrease in the abundance of dense granules and abnormal transparency of rhoptries, leading to a reduction in protein secretion from these organelles. The absence of TgREMIND inhibits host invasion and parasite dissemination, demonstrating that TgREMIND is essential for the proper function of critical secretory organelles required for successful infection by Toxoplasma.
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Affiliation(s)
- Rodrigue Houngue
- Université Paris Saclay, CNRS UMR 9198-CEA, Institute for Integrative Biology of the Cell (I2BC), 91190 Gif sur Yvette, France
| | - Lamba Omar Sangaré
- Department of Biology, Texas A&M University, College Station, TX 77843, USA
| | - Tchilabalo Dilezitoko Alayi
- Department of Pharmaceutical Science, School of Pharmacy and Pharmaceutical Sciences, Binghamton University-SUNY, Johnson City, NY 13790, USA
| | - Aissatou Dieng
- Université Paris Saclay, CNRS UMR 9198-CEA, Institute for Integrative Biology of the Cell (I2BC), 91190 Gif sur Yvette, France
| | - Tristan Bitard-Feildel
- Sorbonne Université, Muséum National d'Histoire Naturelle, UMR CNRS 7590, Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, IMPMC, 75005 Paris, France
| | - Claire Boulogne
- Université Paris Saclay, CNRS UMR 9198-CEA, Institute for Integrative Biology of the Cell (I2BC), 91190 Gif sur Yvette, France; Plateforme Imagerie-Gif, Institut de Biologie Intégrative de la Cellule (I2BC), 91190 Gif sur Yvette, France
| | - Christian Slomianny
- University of Lille, Laboratory of Cell Physiology, INSERM U 1003, 59655 Villeneuve d'Ascq, France
| | - Cynthia Menonve Atindehou
- Université d'Abomey Calavi, Laboratoire de Biochimie et de Biologie Moléculaire, Faculté des Sciences et Technologies, Cotonou, Bénin
| | - Lucie Ayi Fanou
- Université d'Abomey Calavi, Laboratoire de Biochimie et de Biologie Moléculaire, Faculté des Sciences et Technologies, Cotonou, Bénin
| | - Yetrib Hathout
- Department of Pharmaceutical Science, School of Pharmacy and Pharmaceutical Sciences, Binghamton University-SUNY, Johnson City, NY 13790, USA
| | - Isabelle Callebaut
- Sorbonne Université, Muséum National d'Histoire Naturelle, UMR CNRS 7590, Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, IMPMC, 75005 Paris, France
| | - Stanislas Tomavo
- Université Paris Saclay, CNRS UMR 9198-CEA, Institute for Integrative Biology of the Cell (I2BC), 91190 Gif sur Yvette, France.
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12
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Pitman EL, Counihan NA, Modak JK, Chowdury M, Gilson PR, Webb CT, de Koning-Ward TF. Dissecting EXP2 sequence requirements for protein export in malaria parasites. Front Cell Infect Microbiol 2024; 13:1332146. [PMID: 38282616 PMCID: PMC10811066 DOI: 10.3389/fcimb.2023.1332146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Accepted: 12/19/2023] [Indexed: 01/30/2024] Open
Abstract
Apicomplexan parasites that reside within a parasitophorous vacuole harbor a conserved pore-forming protein that enables small-molecule transfer across the parasitophorous vacuole membrane (PVM). In Plasmodium parasites that cause malaria, this nutrient pore is formed by EXP2 which can complement the function of GRA17, an orthologous protein in Toxoplasma gondii. EXP2, however, has an additional function in Plasmodium parasites, serving also as the pore-forming component of the protein export machinery PTEX. To examine how EXP2 can play this additional role, transgenes that encoded truncations of EXP2, GRA17, hybrid GRA17-EXP2, or EXP2 under the transcriptional control of different promoters were expressed in EXP2 knockdown parasites to determine which could complement EXP2 function. This revealed that EXP2 is a unique pore-forming protein, and its protein export role in P. falciparum cannot be complemented by T. gondii GRA17. This was despite the addition of the EXP2 assembly strand and part of the linker helix to GRA17, which are regions necessary for the interaction of EXP2 with the other core PTEX components. This indicates that the body region of EXP2 plays a critical role in PTEX assembly and/or that the absence of other T. gondii GRA proteins in P. falciparum leads to its reduced efficiency of insertion into the PVM and complementation potential. Altering the timing and abundance of EXP2 expression did not affect protein export but affected parasite viability, indicating that the unique transcriptional profile of EXP2 when compared to other PTEX components enables it to serve an additional role in nutrient exchange.
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Affiliation(s)
- Ethan L. Pitman
- School of Medicine, Deakin University, Geelong, VIC, Australia
- Institute for Mental and Physical Health and Clinical Translation (IMPACT), Deakin University, Geelong, VIC, Australia
| | - Natalie A. Counihan
- School of Medicine, Deakin University, Geelong, VIC, Australia
- Institute for Mental and Physical Health and Clinical Translation (IMPACT), Deakin University, Geelong, VIC, Australia
| | - Joyanta K. Modak
- School of Medicine, Deakin University, Geelong, VIC, Australia
- Institute for Mental and Physical Health and Clinical Translation (IMPACT), Deakin University, Geelong, VIC, Australia
| | - Mrittika Chowdury
- School of Medicine, Deakin University, Geelong, VIC, Australia
- Institute for Mental and Physical Health and Clinical Translation (IMPACT), Deakin University, Geelong, VIC, Australia
| | - Paul R. Gilson
- Burnet Institute, Melbourne, VIC, Australia
- Department of Microbiology and Immunology, University of Melbourne, Parkville, VIC, Australia
| | - Chaille T. Webb
- Biomedicine Discovery Institute and Department of Microbiology, Monash University, Clayton, VIC, Australia
- Centre to Impact AMR, Monash University, Clayton, VIC, Australia
| | - Tania F. de Koning-Ward
- School of Medicine, Deakin University, Geelong, VIC, Australia
- Institute for Mental and Physical Health and Clinical Translation (IMPACT), Deakin University, Geelong, VIC, Australia
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13
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Seizova S, Ferrel A, Boothroyd J, Tonkin CJ. Toxoplasma protein export and effector function. Nat Microbiol 2024; 9:17-28. [PMID: 38172621 DOI: 10.1038/s41564-023-01563-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 11/16/2023] [Indexed: 01/05/2024]
Abstract
Toxoplasma gondii is a single-celled eukaryotic parasite with a considerable host range that must invade the cells of warm-blooded hosts to survive and replicate. The challenges and opportunities that such a strategy represent have been met by the evolution of effectors that are delivered into host cells, counter host defences and co-opt host cell functions for their own purposes. These effectors are delivered in two waves using distinct machinery for each. In this Review, we focus on understanding the architecture of these protein-export systems and how their protein cargo is recognized and selected. We discuss the recent findings on the role that host manipulation has in latent Toxoplasma infections. We also discuss how these recent findings compare to protein export in the related Plasmodium spp. (the causative agent of malaria) and how this can inform our understanding of host manipulation in the larger Apicomplexa phylum and its evolution.
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Affiliation(s)
- Simona Seizova
- School of Life Sciences, The University of Dundee, Dundee, UK
| | - Abel Ferrel
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford University, Stanford, CA, USA
| | - John Boothroyd
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford University, Stanford, CA, USA.
| | - Christopher J Tonkin
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia.
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14
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Wang Y, Hollingsworth LR, Sangaré LO, Paredes-Santos TC, Krishnamurthy S, Penn BH, Wu H, Saeij JPJ. Host E3 ubiquitin ligase ITCH mediates Toxoplasma gondii effector GRA35-triggered NLRP1 inflammasome activation and cell-autonomous immunity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.13.571530. [PMID: 38168400 PMCID: PMC10760081 DOI: 10.1101/2023.12.13.571530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Toxoplasma gondii is an intracellular parasite that can activate the NLRP1 inflammasome leading to macrophage pyroptosis in Lewis rats, but the underlying mechanism is not well understood. In this study, we performed a genome-wide CRISPR screen and identified the dense granule proteins GRA35, GRA42, and GRA43 as the Toxoplasma effectors mediating cell death in Lewis rat macrophages. GRA35 localizes on the parasitophorous vacuole membrane, where it interacts with the host E3 ubiquitin ligase ITCH. Inhibition of proteasome activity or ITCH knockout prevented pyroptosis in Toxoplasma-infected Lewis rat macrophages, consistent with the "NLRP1 functional degradation model". However, there was no evidence that ITCH directly ubiquitinates or interacts with rat NLRP1. We also found that GRA35-ITCH interaction affected Toxoplasma fitness in IFNγ-activated human fibroblasts, likely due to ITCH's role in recruiting ubiquitin and the parasite-restriction factor RNF213 to the parasitophorous vacuole membrane. These findings identify a new role of host E3 ubiquitin ligase ITCH in mediating effector-triggered immunity, a critical concept that involves recognizing intracellular pathogens and initiating host innate immune responses.
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Affiliation(s)
- Yifan Wang
- Department of Pathology, Microbiology & Immunology, School of Veterinary Medicine, University of California, Davis, Davis, CA, USA
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - L. Robert Hollingsworth
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, USA
- Program in Cellular and Molecular Medicine, Boston Children’s Hospital, Boston, MA, USA
- Program in Biological and Biomedical Sciences, Harvard Medical School, Boston, MA, USA
| | - Lamba Omar Sangaré
- Department of Pathology, Microbiology & Immunology, School of Veterinary Medicine, University of California, Davis, Davis, CA, USA
- Department of Biology, Texas A&M University, College Station, TX, USA
| | - Tatiana C. Paredes-Santos
- Department of Pathology, Microbiology & Immunology, School of Veterinary Medicine, University of California, Davis, Davis, CA, USA
| | - Shruthi Krishnamurthy
- Department of Pathology, Microbiology & Immunology, School of Veterinary Medicine, University of California, Davis, Davis, CA, USA
| | - Bennett H. Penn
- Department of Internal Medicine, Division of Infectious Diseases, UC Davis Health, Sacramento, CA, USA
- Department of Medical Microbiology and Immunology, University of California, Davis, Davis, CA, USA
| | - Hao Wu
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, USA
- Program in Cellular and Molecular Medicine, Boston Children’s Hospital, Boston, MA, USA
- Program in Biological and Biomedical Sciences, Harvard Medical School, Boston, MA, USA
| | - Jeroen P. J. Saeij
- Department of Pathology, Microbiology & Immunology, School of Veterinary Medicine, University of California, Davis, Davis, CA, USA
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15
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Bitew MA, Gaete PS, Swale C, Maru P, Contreras JE, Saeij JPJ. GRA47 and GRA72 are Toxoplasma gondii pore-forming proteins that influence small molecule permeability of the parasitophorous vacuole. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.15.567216. [PMID: 38014337 PMCID: PMC10680723 DOI: 10.1101/2023.11.15.567216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
Toxoplasma gondii, a medically important intracellular parasite, uses GRA proteins, secreted from dense granule organelles, to mediate nutrient flux across the parasitophorous vacuole membrane (PVM). GRA17 and GRA23 are known pore-forming proteins on the PVM involved in this process, but the roles of additional proteins have remained largely uncharacterized. We recently identified GRA72 as synthetically lethal with GRA17. Deleting GRA72 produced similar phenotypes to Δgra17 parasites, and computational predictions suggested it forms a pore. To understand how GRA72 functions we performed immunoprecipitation experiments and identified GRA47 as an interactor of GRA72. Deletion of GRA47 resulted in an aberrant 'bubble vacuole' morphology with reduced small molecule permeability, mirroring the phenotype observed in GRA17 and GRA72 knockouts. Structural predictions indicated that GRA47 and GRA72 form heptameric and hexameric pores, respectively, with conserved histidine residues lining the pore. Mutational analysis highlighted the critical role of these histidines for protein functionality. Validation through electrophysiology confirmed alterations in membrane conductance, corroborating their pore-forming capabilities. Furthermore, Δgra47 parasites and parasites expressing GRA47 with a histidine mutation had reduced in vitro proliferation and attenuated virulence in mice. Our findings show the important roles of GRA47 and GRA72 in regulating PVM permeability, thereby expanding the repertoire of potential therapeutic targets against Toxoplasma infections.
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Affiliation(s)
- Mebratu A. Bitew
- Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California, Davis. Davis, California, USA
| | - Pablo S. Gaete
- Department of Physiology and Membrane Biology, University of California, Davis. Davis, California, USA
| | - Christopher Swale
- Team Host-Pathogen Interactions and Immunity to Infection, Institute for Advanced Biosciences (IAB), INSERM U1209, CNRS UMR5309, University Grenoble Alpes, Grenoble, France
| | - Parag Maru
- Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California, Davis. Davis, California, USA
| | - Jorge E. Contreras
- Department of Physiology and Membrane Biology, University of California, Davis. Davis, California, USA
| | - Jeroen P. J. Saeij
- Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California, Davis. Davis, California, USA
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16
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Henshall IG, Spielmann T. Critical interdependencies between Plasmodium nutrient flux and drugs. Trends Parasitol 2023; 39:936-944. [PMID: 37716852 PMCID: PMC10580322 DOI: 10.1016/j.pt.2023.08.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 08/23/2023] [Accepted: 08/24/2023] [Indexed: 09/18/2023]
Abstract
Nutrient import and waste efflux are critical dependencies for intracellular Plasmodium falciparum parasites. Nutrient transport proteins are often lineage specific and can provide unique targets for antimalarial drug development. P. falciparum nutrient transport pathways can be a double-edged sword for the parasite, not only mediating the import of nutrients and excretion of waste products but also providing an access route for drugs. Here we briefly summarise the nutrient acquisition pathways of intracellular P. falciparum blood-stage parasites and then highlight how these pathways influence many aspects relevant to antimalarial drugs, resulting in complex and often underappreciated interdependencies.
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Affiliation(s)
| | - Tobias Spielmann
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany.
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17
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Ferrel A, Romano J, Panas MW, Coppens I, Boothroyd JC. Host MOSPD2 enrichment at the parasitophorous vacuole membrane varies between Toxoplasma strains and involves complex interactions. mSphere 2023; 8:e0067022. [PMID: 37341482 PMCID: PMC10449529 DOI: 10.1128/msphere.00670-22] [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: 12/22/2022] [Accepted: 04/25/2023] [Indexed: 06/22/2023] Open
Abstract
Toxoplasma gondii is an obligate, intracellular parasite. Infection of a cell produces a unique niche for the parasite named the parasitophorous vacuole (PV) initially composed of host plasma membrane invaginated during invasion. The PV and its membrane (parasitophorous vacuole membrane [PVM]) are subsequently decorated with a variety of parasite proteins allowing the parasite to optimally grow in addition to manipulate host processes. Recently, we reported a proximity-labeling screen at the PVM-host interface and identified host endoplasmic reticulum (ER)-resident motile sperm domain-containing protein 2 (MOSPD2) as being enriched at this location. Here we extend these findings in several important respects. First, we show that the extent and pattern of host MOSPD2 association with the PVM differ dramatically in cells infected with different strains of Toxoplasma. Second, in cells infected with Type I RH strain, the MOSPD2 staining is mutually exclusive with regions of the PVM that associate with mitochondria. Third, immunoprecipitation and liquid chromatography tandem mass spectrometry (LC-MS/MS) with epitope-tagged MOSPD2-expressing host cells reveal strong enrichment of several PVM-localized parasite proteins, although none appear to play an essential role in MOSPD2 association. Fourth, most MOSPD2 associating with the PVM is newly translated after infection of the cell and requires the major functional domains of MOSPD2, identified as the CRAL/TRIO domain and tail anchor, although these domains were not sufficient for PVM association. Lastly, ablation of MOSPD2 results in, at most, a modest impact on Toxoplasma growth in vitro. Collectively, these studies provide new insight into the molecular interactions involving MOSPD2 at the dynamic interface between the PVM and the host cytosol. IMPORTANCE Toxoplasma gondii is an intracellular pathogen that lives within a membranous vacuole inside of its host cell. This vacuole is decorated by a variety of parasite proteins that allow it to defend against host attack, acquire nutrients, and interact with the host cell. Recent work identified and validated host proteins enriched at this host-pathogen interface. Here, we follow up on one candidate named MOSPD2 shown to be enriched at the vacuolar membrane and describe it as having a dynamic interaction at this location depending on a variety of factors. Some of these include the presence of host mitochondria, intrinsic domains of the host protein, and whether translation is active. Importantly, we show that MOSPD2 enrichment at the vacuole membrane differs between strains indicating active involvement of the parasite with this phenotype. Altogether, these results shed light on the mechanism and role of protein associations in the host-pathogen interaction.
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Affiliation(s)
- Abel Ferrel
- Department of Microbiology and Immunology, Stanford School of Medicine, Stanford, California, USA
| | - Julia Romano
- Department of Molecular Microbiology and Immunology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Michael W. Panas
- Department of Microbiology and Immunology, Stanford School of Medicine, Stanford, California, USA
| | - Isabelle Coppens
- Department of Molecular Microbiology and Immunology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - John C. Boothroyd
- Department of Microbiology and Immunology, Stanford School of Medicine, Stanford, California, USA
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18
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Fierro MA, Hussain T, Campin LJ, Beck JR. Knock-sideways by inducible ER retrieval enables a unique approach for studying Plasmodium-secreted proteins. Proc Natl Acad Sci U S A 2023; 120:e2308676120. [PMID: 37552754 PMCID: PMC10433460 DOI: 10.1073/pnas.2308676120] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Accepted: 06/26/2023] [Indexed: 08/10/2023] Open
Abstract
Malaria parasites uniquely depend on protein secretion for their obligate intracellular lifestyle but approaches for dissecting Plasmodium-secreted protein functions are limited. We report knockER, a unique DiCre-mediated knock-sideways approach to sequester secreted proteins in the ER by inducible fusion with a KDEL ER-retrieval sequence. We show conditional ER sequestration of diverse proteins is not generally toxic, enabling loss-of-function studies. We employed knockER in multiple Plasmodium species to interrogate the trafficking, topology, and function of an assortment of proteins that traverse the secretory pathway to diverse compartments including the apicoplast (ClpB1), rhoptries (RON6), dense granules, and parasitophorous vacuole (EXP2, PTEX150, HSP101). Taking advantage of the unique ability to redistribute secreted proteins from their terminal destination to the ER, we reveal that vacuolar levels of the PTEX translocon component HSP101 but not PTEX150 are maintained in excess of what is required to sustain effector protein export into the erythrocyte. Intriguingly, vacuole depletion of HSP101 hypersensitized parasites to a destabilization tag that inhibits HSP101-PTEX complex formation but not to translational knockdown of the entire HSP101 pool, illustrating how redistribution of a target protein by knockER can be used to query function in a compartment-specific manner. Collectively, our results establish knockER as a unique tool for dissecting secreted protein function with subcompartmental resolution that should be widely amenable to genetically tractable eukaryotes.
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Affiliation(s)
- Manuel A. Fierro
- Department of Biomedical Sciences, Iowa State University, Ames, IA50011
| | - Tahir Hussain
- Department of Biomedical Sciences, Iowa State University, Ames, IA50011
| | - Liam J. Campin
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA50011
| | - Josh R. Beck
- Department of Biomedical Sciences, Iowa State University, Ames, IA50011
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA50011
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19
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Paredes-Santos TC, Bitew MA, Swale C, Rodriguez F, Krishnamurthy S, Wang Y, Maru P, Sangaré LO, Saeij JPJ. Genome-wide CRISPR screen identifies genes synthetically lethal with GRA17, a nutrient channel encoding gene in Toxoplasma. PLoS Pathog 2023; 19:e1011543. [PMID: 37498952 PMCID: PMC10409377 DOI: 10.1371/journal.ppat.1011543] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 08/08/2023] [Accepted: 07/06/2023] [Indexed: 07/29/2023] Open
Abstract
Toxoplasma gondii is a parasite that replicates within a specialized compartment called the parasitophorous vacuole (PV), which is surrounded by the PV membrane (PVM). To obtain essential nutrients, Toxoplasma must transport molecules across the PVM, a process mediated by the secreted parasite proteins GRA17 and GRA23. These proteins form pores in the PVM through which small molecules can diffuse in and out of the PV. GRA17 and GRA23 are synthetically lethal, suggesting that at least one pore type is essential for parasite survival. In the 'nutrient sensitized' Δgra17 strain it is likely that other Toxoplasma genes become essential, because they mediate nutrient acquisition from the host or are involved in the trafficking of GRA23 to the PVM. To identify these genes, a genome-wide loss-of-function screen was performed in wild-type and Δgra17 parasites, which identified multiple genes that were synthetically sick/lethal with GRA17. Several of these genes were involved in the correct localization of GRAs, including GRA17/GRA23, to the PVM. One of the top hits, GRA72, was predicted to form a pore on the PVM, and its deletion led to the formation of enlarged "bubble vacuoles" with reduced PVM small molecule permeability, similar to what was previously observed for Δgra17 parasites. Furthermore, Δgra72 parasites had reduced in vitro growth and virulence in mice. These findings suggest that in the absence of GRA17, other genes become essential, likely because they play a role in the proper localization of GRA23 (and other GRAs) or because they determine host-derived nutrient acquisition at the PVM.
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Affiliation(s)
- Tatiana C. Paredes-Santos
- Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California Davis, Davis, California, United States of America
| | - Mebratu A. Bitew
- Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California Davis, Davis, California, United States of America
| | - Christopher Swale
- Team Host-Pathogen Interactions and Immunity to Infection, Institute for Advanced Biosciences (IAB), INSERM U1209, CNRS UMR5309, University Grenoble Alpes, Grenoble, France
| | - Felipe Rodriguez
- Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California Davis, Davis, California, United States of America
| | - Shruthi Krishnamurthy
- Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California Davis, Davis, California, United States of America
| | - Yifan Wang
- Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California Davis, Davis, California, United States of America
| | - Parag Maru
- Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California Davis, Davis, California, United States of America
| | - Lamba Omar Sangaré
- Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California Davis, Davis, California, United States of America
| | - Jeroen P. J. Saeij
- Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California Davis, Davis, California, United States of America
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20
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Tachibana Y, Hashizaki E, Sasai M, Yamamoto M. Host genetics highlights IFN-γ-dependent Toxoplasma genes encoding secreted and non-secreted virulence factors in in vivo CRISPR screens. Cell Rep 2023; 42:112592. [PMID: 37269286 DOI: 10.1016/j.celrep.2023.112592] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 04/25/2023] [Accepted: 05/17/2023] [Indexed: 06/05/2023] Open
Abstract
Secreted virulence factors of Toxoplasma to survive in immune-competent hosts have been extensively explored by classical genetics and in vivo CRISPR screen methods, whereas their requirements in immune-deficient hosts are incompletely understood. Those of non-secreted virulence factors are further enigmatic. Here we develop an in vivo CRISPR screen system to enrich not only secreted but also non-secreted virulence factors in virulent Toxoplasma-infected C57BL/6 mice. Notably, combined usage of immune-deficient Ifngr1-/- mice highlights genes encoding various non-secreted proteins as well as well-known effectors such as ROP5, ROP18, GRA12, and GRA45 as interferon-γ (IFN-γ)-dependent virulence genes. The screen results suggest a role of GRA72 for normal GRA17/GRA23 localization and the IFN-γ-dependent role of UFMylation-related genes. Collectively, our study demonstrates that host genetics can complement in vivo CRISPR screens to highlight genes encoding IFN-γ-dependent secreted and non-secreted virulence factors in Toxoplasma.
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Affiliation(s)
- Yuta Tachibana
- Department of Immunoparasitology, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan; Laboratory of Immunoparasitology, WPI Immunology Frontier Research Center, Osaka University, Suita, Osaka, Japan
| | - Emi Hashizaki
- Department of Immunoparasitology, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan; Laboratory of Immunoparasitology, WPI Immunology Frontier Research Center, Osaka University, Suita, Osaka, Japan
| | - Miwa Sasai
- Department of Immunoparasitology, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan; Laboratory of Immunoparasitology, WPI Immunology Frontier Research Center, Osaka University, Suita, Osaka, Japan; Department of Immunoparasitology, Center for Infectious Disease Education and Research, Osaka University, Suita, Osaka 565-0871, Japan
| | - Masahiro Yamamoto
- Department of Immunoparasitology, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan; Laboratory of Immunoparasitology, WPI Immunology Frontier Research Center, Osaka University, Suita, Osaka, Japan; Department of Immunoparasitology, Center for Infectious Disease Education and Research, Osaka University, Suita, Osaka 565-0871, Japan.
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21
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Diao Y, Yao Y, El-Ashram S, Bian M. Egress Regulatory Factors: How Toxoplasma Exits from Infected Cells? Pathogens 2023; 12:pathogens12050679. [PMID: 37242349 DOI: 10.3390/pathogens12050679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 04/29/2023] [Accepted: 05/02/2023] [Indexed: 05/28/2023] Open
Abstract
Toxoplasma gondii is an obligatory intracellular protozoan in the family Apicomplexa. It infects almost one-third of the world's population and causes toxoplasmosis, a prevalent disease. The parasite's egress from infected cells is a key step in the pathology caused by T. gondii. Moreover, T. gondii's continuous infection relies heavily on its capacity to migrate from one cell to another. Many pathways are involved in T. gondii egress. Individual routes may be modified to respond to various environmental stimuli, and many paths can converge. Regardless of the stimuli, the relevance of Ca2+ as a second messenger in transducing these signals, and the convergence of various signaling pathways in the control of motility and, ultimately, egress, is well recognized. This review attempts to outline intra- and extra-parasitic regulators that mediate T. gondii egress, and provides insight into potential clinical interventions and research.
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Affiliation(s)
- Yujie Diao
- Department of Blood Transfusion, The First Affiliated Hospital of Anhui Medical University, Hefei 230032, China
| | - Yong Yao
- College of Life Sciences, Anhui Medical University, Hefei 230032, China
| | - Saeed El-Ashram
- College of Life Science and Engineering, Foshan University, 18 Jiangwan Street, Foshan 528231, China
- Faculty of Science, Kafrelsheikh University, Kafr El-Sheikh 33516, Egypt
| | - Maohong Bian
- Department of Blood Transfusion, The First Affiliated Hospital of Anhui Medical University, Hefei 230032, China
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22
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Mosqueda J, Hernandez-Silva DJ, Ueti MW, Cruz-Reséndiz A, Marquez-Cervantez R, Valdez-Espinoza UM, Dang-Trinh MA, Nguyen TT, Camacho-Nuez M, Mercado-Uriostegui MA, Aguilar-Tipacamú G, Ramos-Aragon JA, Hernandez-Ortiz R, Kawazu SI, Igarashi I. Spherical Body Protein 4 from Babesia bigemina: A Novel Gene That Contains Conserved B-Cell Epitopes and Induces Cross-Reactive Neutralizing Antibodies in Babesia ovata. Pathogens 2023; 12:pathogens12030495. [PMID: 36986418 PMCID: PMC10051436 DOI: 10.3390/pathogens12030495] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2023] [Revised: 03/18/2023] [Accepted: 03/20/2023] [Indexed: 03/30/2023] Open
Abstract
Bovine babesiosis is a tick-transmitted disease caused by intraerythrocytic protozoan parasites of the genus Babesia. Its main causative agents in the Americas are Babesia bigemina and Babesia bovis, while Babesia ovata affects cattle in Asia. All Babesia species secrete proteins stored in organelles of the apical complex, which are involved in all steps of the invasion process of vertebrate host cells. Unlike other apicomplexans, which have dense granules, babesia parasites instead have large, round intracellular organelles called spherical bodies. Evidence suggests that proteins from these organelles are released during the process of invading red blood cells, where spherical body proteins (SBPs) play an important role in cytoskeleton reorganization. In this study, we characterized the gene that encodes SBP4 in B. bigemina. This gene is transcribed and expressed in the erythrocytic stages of B. bigemina. The sbp4 gene consists of 834 nucleotides without introns that encode a protein of 277 amino acids. In silico analysis predicted a signal peptide that is cleaved at residue 20, producing a 28.88-kDa protein. The presence of a signal peptide and the absence of transmembrane domains suggest that this protein is secreted. Importantly, when cattle were immunized with recombinant B. bigemina SBP4, antibodies identified B. bigemina and B. ovata merozoites according to confocal microscopy observations and were able to neutralize parasite multiplication in vitro for both species. Four peptides with predicted B-cell epitopes were identified to be conserved in 17 different isolates from six countries. Compared with the pre-immunization sera, antibodies against these conserved peptides reduced parasite invasion in vitro by 57%, 44%, 42%, and 38% for peptides 1, 2, 3, and 4, respectively (p < 0.05). Moreover, sera from cattle infected with B. bigemina cattle contained antibodies that recognized the individual peptides. All these results support the concept of spb4 as a new gene in B. bigemina that should be considered a candidate for a vaccine to control bovine babesiosis.
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Affiliation(s)
- Juan Mosqueda
- Immunology and Vaccines Laboratory, C. A. Facultad de Ciencias Naturales, Universidad Autonoma de Queretaro, Carretera a Chichimequillas, Ejido Bolaños, Queretaro 76140, Mexico
- C.A. Salud Animal y Microbiologia Ambiental, Facultad de Ciencias Naturales, Universidad Autonoma de Queretaro, Av. de las Ciencias s/n Col Juriquilla, Queretaro 76230, Mexico
| | - Diego Josimar Hernandez-Silva
- Immunology and Vaccines Laboratory, C. A. Facultad de Ciencias Naturales, Universidad Autonoma de Queretaro, Carretera a Chichimequillas, Ejido Bolaños, Queretaro 76140, Mexico
- Ph.D. Program in Biological Sciences, College of Natural Sciences, Autonomous University of Queretaro, Av. de las Ciencias s/n Col Juriquilla, Queretaro 76230, Mexico
| | - Massaro W Ueti
- Animal Diseases Research Unit, Agricultural Research Service, US Department of Agriculture, Pullman, WA 99164, USA
| | - Adolfo Cruz-Reséndiz
- Immunology and Vaccines Laboratory, C. A. Facultad de Ciencias Naturales, Universidad Autonoma de Queretaro, Carretera a Chichimequillas, Ejido Bolaños, Queretaro 76140, Mexico
- Veterinary Medicine Program, College of Natural Sciences, Autonomous University of Queretaro, Av. de las Ciencias s/n Col Juriquilla, Queretaro 76230, Mexico
| | - Ricardo Marquez-Cervantez
- Immunology and Vaccines Laboratory, C. A. Facultad de Ciencias Naturales, Universidad Autonoma de Queretaro, Carretera a Chichimequillas, Ejido Bolaños, Queretaro 76140, Mexico
- Veterinary Medicine Program, College of Natural Sciences, Autonomous University of Queretaro, Av. de las Ciencias s/n Col Juriquilla, Queretaro 76230, Mexico
| | - Uriel Mauricio Valdez-Espinoza
- Immunology and Vaccines Laboratory, C. A. Facultad de Ciencias Naturales, Universidad Autonoma de Queretaro, Carretera a Chichimequillas, Ejido Bolaños, Queretaro 76140, Mexico
- Master's Program in Animal Health and Production, Facultad de Medicina Veterinaria y Zootecnia, Universidad Nacional Autonoma de Mexico, Av. Universidad 3000, Edificio A, Delegacion Coyoacan, Col. Ciudad Universitaria, Mexico City 04510, Mexico
- CENID-Salud Animal e Inocuidad/INIFAP, Carretera Federal Cuernavaca-Cuautla #8534, Col. Progreso, Jiutepec 62574, Mexico
| | - Minh-Anh Dang-Trinh
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro 080-8555, Japan
| | - Thu-Thuy Nguyen
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro 080-8555, Japan
| | - Minerva Camacho-Nuez
- Posgrado en Ciencias Genomicas, Universidad Autonoma de la Ciudad de Mexico, San Lorenzo 290, Esquina Roberto Gayol, Col. del Valle Sur, Delegacion Benito Juarez, Mexico City 03100, Mexico
| | - Miguel Angel Mercado-Uriostegui
- Immunology and Vaccines Laboratory, C. A. Facultad de Ciencias Naturales, Universidad Autonoma de Queretaro, Carretera a Chichimequillas, Ejido Bolaños, Queretaro 76140, Mexico
- C.A. Salud Animal y Microbiologia Ambiental, Facultad de Ciencias Naturales, Universidad Autonoma de Queretaro, Av. de las Ciencias s/n Col Juriquilla, Queretaro 76230, Mexico
| | - Gabriela Aguilar-Tipacamú
- C.A. Salud Animal y Microbiologia Ambiental, Facultad de Ciencias Naturales, Universidad Autonoma de Queretaro, Av. de las Ciencias s/n Col Juriquilla, Queretaro 76230, Mexico
| | - Juan Alberto Ramos-Aragon
- CENID-Salud Animal e Inocuidad/INIFAP, Carretera Federal Cuernavaca-Cuautla #8534, Col. Progreso, Jiutepec 62574, Mexico
| | - Ruben Hernandez-Ortiz
- CENID-Salud Animal e Inocuidad/INIFAP, Carretera Federal Cuernavaca-Cuautla #8534, Col. Progreso, Jiutepec 62574, Mexico
| | - Shin-Ichiro Kawazu
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro 080-8555, Japan
| | - Ikuo Igarashi
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro 080-8555, Japan
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23
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CRISPR Screens Identify Toxoplasma Genes That Determine Parasite Fitness in Interferon Gamma-Stimulated Human Cells. mBio 2023; 14:e0006023. [PMID: 36916910 PMCID: PMC10128063 DOI: 10.1128/mbio.00060-23] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023] Open
Abstract
Toxoplasma virulence depends on its ability to evade or survive the toxoplasmacidal mechanisms induced by interferon gamma (IFNγ). While many Toxoplasma genes involved in the evasion of the murine IFNγ response have been identified, genes required to survive the human IFNγ response are largely unknown. In this study, we used a genome-wide loss-of-function screen to identify Toxoplasma genes important for parasite fitness in IFNγ-stimulated primary human fibroblasts. We generated gene knockouts for the top six hits from the screen and confirmed their importance for parasite growth in IFNγ-stimulated human fibroblasts. Of these six genes, three have homology to GRA32, localize to dense granules, and coimmunoprecipitate with each other and GRA32, suggesting they might form a complex. Deletion of individual members of this complex leads to early parasite egress in IFNγ-stimulated cells. Thus, prevention of early egress is an important Toxoplasma fitness determinant in IFNγ-stimulated human cells. IMPORTANCE Toxoplasma infection causes serious complications in immunocompromised individuals and in the developing fetus. During infection, certain immune cells release a protein called interferon gamma that activates cells to destroy the parasite or inhibit its growth. While most Toxoplasma parasites are cleared by this immune response, some can survive by blocking or evading the IFNγ-induced restrictive environment. Many Toxoplasma genes that determine parasite survival in IFNγ-activated murine cells are known but parasite genes conferring fitness in IFNγ-activated human cells are largely unknown. Using a Toxoplasma adapted genome-wide loss-of-function screen, we identified many Toxoplasma genes that determine parasite fitness in IFNγ-activated human cells. The gene products of four top hits play a role in preventing early parasite egress in IFNγ-stimulated human cells. Understanding how IFNγ-stimulated human cells inhibit Toxoplasma growth and how Toxoplasma counteracts this, could lead to the development of novel therapeutics.
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24
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Giuliano CJ, Wei KJ, Harling FM, Waldman BS, Farringer MA, Boydston EA, Lan TCT, Thomas RW, Herneisen AL, Sanderlin AG, Coppens I, Dvorin JD, Lourido S. Functional profiling of the Toxoplasma genome during acute mouse infection. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.05.531216. [PMID: 36945434 PMCID: PMC10028831 DOI: 10.1101/2023.03.05.531216] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/12/2023]
Abstract
Within a host, pathogens encounter a diverse and changing landscape of cell types, nutrients, and immune responses. Examining host-pathogen interactions in animal models can therefore reveal aspects of infection absent from cell culture. We use CRISPR-based screens to functionally profile the entire genome of the model apicomplexan parasite Toxoplasma gondii during mouse infection. Barcoded gRNAs were used to track mutant parasite lineages, enabling detection of bottlenecks and mapping of population structures. We uncovered over 300 genes that modulate parasite fitness in mice with previously unknown roles in infection. These candidates span multiple axes of host-parasite interaction, including determinants of tropism, host organelle remodeling, and metabolic rewiring. We mechanistically characterized three novel candidates, including GTP cyclohydrolase I, against which a small-molecule inhibitor could be repurposed as an antiparasitic compound. This compound exhibited antiparasitic activity against T. gondii and Plasmodium falciparum, the most lethal agent of malaria. Taken together, we present the first complete survey of an apicomplexan genome during infection of an animal host, and point to novel interfaces of host-parasite interaction that may offer new avenues for treatment.
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Affiliation(s)
| | - Kenneth J. Wei
- Whitehead Institute, Cambridge, MA
- Biology Department, MIT, Cambridge, MA
| | - Faye M. Harling
- Whitehead Institute, Cambridge, MA
- Biology Department, MIT, Cambridge, MA
| | | | - Madeline A. Farringer
- Division of Infectious Diseases, Boston Children’s Hospital, Boston, Massachusetts, USA
- Biological Sciences in Public Health, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, USA
| | | | | | - Raina W. Thomas
- Whitehead Institute, Cambridge, MA
- Biology Department, MIT, Cambridge, MA
| | - Alice L. Herneisen
- Whitehead Institute, Cambridge, MA
- Biology Department, MIT, Cambridge, MA
| | | | - Isabelle Coppens
- Department of Molecular Microbiology and Immunology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD
| | - Jeffrey D. Dvorin
- Division of Infectious Diseases, Boston Children’s Hospital, Boston, Massachusetts, USA
- Department of Pediatrics, Harvard Medical School, Boston, Massachusetts, USA
| | - Sebastian Lourido
- Whitehead Institute, Cambridge, MA
- Biology Department, MIT, Cambridge, MA
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25
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Wan W, Dong H, Lai DH, Yang J, He K, Tang X, Liu Q, Hide G, Zhu XQ, Sibley LD, Lun ZR, Long S. The Toxoplasma micropore mediates endocytosis for selective nutrient salvage from host cell compartments. Nat Commun 2023; 14:977. [PMID: 36813769 PMCID: PMC9947163 DOI: 10.1038/s41467-023-36571-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Accepted: 02/03/2023] [Indexed: 02/24/2023] Open
Abstract
Apicomplexan parasite growth and replication relies on nutrient acquisition from host cells, in which intracellular multiplication occurs, yet the mechanisms that underlie the nutrient salvage remain elusive. Numerous ultrastructural studies have documented a plasma membrane invagination with a dense neck, termed the micropore, on the surface of intracellular parasites. However, the function of this structure remains unknown. Here we validate the micropore as an essential organelle for endocytosis of nutrients from the host cell cytosol and Golgi in the model apicomplexan Toxoplasma gondii. Detailed analyses demonstrated that Kelch13 is localized at the dense neck of the organelle and functions as a protein hub at the micropore for endocytic uptake. Intriguingly, maximal activity of the micropore requires the ceramide de novo synthesis pathway in the parasite. Thus, this study provides insights into the machinery underlying acquisition of host cell-derived nutrients by apicomplexan parasites that are otherwise sequestered from host cell compartments.
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Affiliation(s)
- Wenyan Wan
- National Key Laboratory of Veterinary Public Health Security and School of Veterinary Medicine, China Agricultural University, 100193, Beijing, China
| | - Hui Dong
- National Key Laboratory of Veterinary Public Health Security and School of Veterinary Medicine, China Agricultural University, 100193, Beijing, China
| | - De-Hua Lai
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510275, China
| | - Jiong Yang
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510275, China
| | - Kai He
- National Key Laboratory of Veterinary Public Health Security and School of Veterinary Medicine, China Agricultural University, 100193, Beijing, China
| | - Xiaoyan Tang
- National Key Laboratory of Veterinary Public Health Security and School of Veterinary Medicine, China Agricultural University, 100193, Beijing, China
| | - Qun Liu
- National Key Laboratory of Veterinary Public Health Security and School of Veterinary Medicine, China Agricultural University, 100193, Beijing, China
| | - Geoff Hide
- Biomedical Research and Innovation Centre and Environmental Research and Innovation Centre, School of Science, Engineering and Environment, University of Salford, Salford, M5 4WT, UK
| | - Xing-Quan Zhu
- College of Veterinary Medicine, Shanxi Agricultural University, Taigu, 030801, Shanxi, China
| | - L David Sibley
- Department of Molecular Microbiology, Washington University School of Medicine in Saint Louis, Saint Louis, MO, 63110-1093, USA
| | - Zhao-Rong Lun
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510275, China
| | - Shaojun Long
- National Key Laboratory of Veterinary Public Health Security and School of Veterinary Medicine, China Agricultural University, 100193, Beijing, China.
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26
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Functional Characterization of 15 Novel Dense Granule Proteins in Toxoplasma gondii Using the CRISPR-Cas9 System. Microbiol Spectr 2023; 11:e0307822. [PMID: 36515555 PMCID: PMC9927372 DOI: 10.1128/spectrum.03078-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The analysis of the subcellular localization and function of dense granule proteins (GRAs) is of central importance for the understanding of host-parasite interaction and pathogenesis of Toxoplasma gondii infection. Here, we identified 15 novel GRAs and used C-terminal endogenous gene tagging to determine their localization at the intravacuolar network (IVN), parasitophorous vacuole (PV), or PV membrane (PVM) in the tachyzoites and at the periphery of the bradyzoites-containing cysts. The functions of the 15 gra genes were examined in type I RH strain and 5 of these gra genes were also evaluated in the cyst-forming type II Pru strain. The 15 novel gra genes were successfully disrupted by using CRISPR-Cas9 mediated homologous recombination and the results showed that 13 gra genes were not individually essential for T. gondii replication in vitro or virulence in mice during acute and chronic infection. Intriguingly, deletion of TGME49_266410 and TGME49_315910 in both RH and Pru strains decreased the parasite replication in vitro and attenuated its virulence, and also reduced the cyst-forming ability of the Pru strain in mice during chronic infection. Comparison of the transcriptomic profiles of the 15 gra genes suggests that they may play roles in other life cycle stages and genotypes of T. gondii. Taken together, our findings improve the understanding of T. gondii pathogenesis and demonstrate the involvement of two novel GRAs, TGME49_266410 and TGME49_315910, in the parasite replication and virulence. IMPORTANCE Dense granule proteins (GRAs) play important roles in Toxoplasma gondii pathogenicity. However, the functions of many putative GRAs have not been elucidated. Here, we found that 15 novel GRAs are secreted into intravacuolar network (IVN), parasitophorous vacuole (PV), or PV membrane (PVM) in tachyzoites and are located at the periphery of the bradyzoite-containing cysts. TGME49_266410 and TGME49_315910 were crucial to the growth of RH and Pru strains in vitro. Deletion of TGME49_266410 and TGME49_315910 attenuated the parasite virulence in mice. However, disruption of other 13 gra genes did not have a significant impact on the proliferation and pathogenicity of T. gondii in vitro or in vivo. The marked effects of the two novel GRAs (TGME49_266410 and TGME49_315910) on the in vitro growth and virulence of T. gondii are notable and warrant further elucidation of the temporal and spatial dynamics of translocation of these two novel GRAs and how do they interfere with host cell functions.
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27
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A. PORTES JULIANA, C. VOMMARO ROSSIANE, AYRES CALDAS LUCIO, S. MARTINS-DUARTE ERICA. Intracellular life of protozoan Toxoplasma gondii: Parasitophorous vacuole establishment and survival strategies. BIOCELL 2023. [DOI: 10.32604/biocell.2023.026629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/11/2023]
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28
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Down the membrane hole: Ion channels in protozoan parasites. PLoS Pathog 2022; 18:e1011004. [PMID: 36580479 PMCID: PMC9799330 DOI: 10.1371/journal.ppat.1011004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Parasitic diseases caused by protozoans are highly prevalent around the world, disproportionally affecting developing countries, where coinfection with other microorganisms is common. Control and treatment of parasitic infections are constrained by the lack of specific and effective drugs, plus the rapid emergence of resistance. Ion channels are main drug targets for numerous diseases, but their potential against protozoan parasites is still untapped. Ion channels are membrane proteins expressed in all types of cells, allowing for the flow of ions between compartments, and regulating cellular functions such as membrane potential, excitability, volume, signaling, and death. Channels and transporters reside at the interface between parasites and their hosts, controlling nutrient uptake, viability, replication, and infectivity. To understand how ion channels control protozoan parasites fate and to evaluate their suitability for therapeutics, we must deepen our knowledge of their structure, function, and modulation. However, methodological approaches commonly used in mammalian cells have proven difficult to apply in protozoans. This review focuses on ion channels described in protozoan parasites of clinical relevance, mainly apicomplexans and trypanosomatids, highlighting proteins for which molecular and functional evidence has been correlated with their physiological functions.
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29
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Hussain T, Linera-Gonzalez J, Beck JM, Fierro MA, Mair GR, Smith RC, Beck JR. The PTEX Pore Component EXP2 Is Important for Intrahepatic Development during the Plasmodium Liver Stage. mBio 2022; 13:e0309622. [PMID: 36445080 PMCID: PMC9765067 DOI: 10.1128/mbio.03096-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Accepted: 11/10/2022] [Indexed: 12/02/2022] Open
Abstract
During vertebrate infection, obligate intracellular malaria parasites develop within a parasitophorous vacuole, which constitutes the interface between the parasite and its hepatocyte or erythrocyte host cells. To traverse this barrier, Plasmodium spp. utilize a dual-function pore formed by EXP2 for nutrient transport and, in the context of the PTEX translocon, effector protein export across the vacuole membrane. While critical to blood-stage survival, less is known about EXP2/PTEX function in the liver stage, although major differences in the export mechanism are suggested by absence of the PTEX unfoldase HSP101 in the intrahepatic vacuole. Here, we employed the glucosamine-activated glmS ribozyme to study the role of EXP2 during Plasmodium berghei liver-stage development in hepatoma cells. Insertion of the glmS sequence into the exp2 3' untranslated region (UTR) enabled glucosamine-dependent depletion of EXP2 after hepatocyte invasion, allowing separation of EXP2 function during intrahepatic development from a recently reported role in hepatocyte invasion. Postinvasion EXP2 knockdown reduced parasite size and largely abolished expression of the mid- to late-liver-stage marker LISP2. As an orthogonal approach to monitor development, EXP2-glmS parasites and controls were engineered to express nanoluciferase. Activation of glmS after invasion substantially decreased luminescence in hepatoma monolayers and in culture supernatants at later time points corresponding to merosome detachment, which marks the culmination of liver-stage development. Collectively, our findings extend the utility of the glmS ribozyme to study protein function in the liver stage and reveal that EXP2 is important for intrahepatic parasite development, indicating that PTEX components also function at the hepatocyte-parasite interface. IMPORTANCE After the mosquito bite that initiates a Plasmodium infection, parasites first travel to the liver and develop in hepatocytes. This liver stage is asymptomatic but necessary for the parasite to transition to the merozoite form, which infects red blood cells and causes malaria. To take over their host cells, avoid immune defenses, and fuel their growth, these obligately intracellular parasites must import nutrients and export effector proteins across a vacuole membrane in which they reside. In the blood stage, these processes depend on a translocon called PTEX, but it is unclear if PTEX also functions during the liver stage. Here, we adapted the glmS ribozyme to control expression of EXP2, the membrane pore component of PTEX, during the liver stage of the rodent malaria parasite Plasmodium berghei. Our results show that EXP2 is important for intracellular development in the hepatocyte, revealing that PTEX components are also functionally important during liver-stage infection.
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Affiliation(s)
- Tahir Hussain
- Department of Biomedical Sciences, Iowa State University, Ames, Iowa, USA
| | | | - John M. Beck
- Department of Biomedical Sciences, Iowa State University, Ames, Iowa, USA
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, Iowa, USA
| | - Manuel A. Fierro
- Department of Biomedical Sciences, Iowa State University, Ames, Iowa, USA
| | - Gunnar R. Mair
- Department of Biomedical Sciences, Iowa State University, Ames, Iowa, USA
| | - Ryan C. Smith
- Department of Plant Pathology, Entomology and Microbiology, Iowa State University, Ames, Iowa, USA
| | - Josh R. Beck
- Department of Biomedical Sciences, Iowa State University, Ames, Iowa, USA
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, Iowa, USA
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Niu Z, Ye S, Liu J, Lyu M, Xue L, Li M, Lyu C, Zhao J, Shen B. Two apicoplast dwelling glycolytic enzymes provide key substrates for metabolic pathways in the apicoplast and are critical for Toxoplasma growth. PLoS Pathog 2022; 18:e1011009. [PMID: 36449552 PMCID: PMC9744290 DOI: 10.1371/journal.ppat.1011009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Revised: 12/12/2022] [Accepted: 11/20/2022] [Indexed: 12/05/2022] Open
Abstract
Many apicomplexan parasites harbor a non-photosynthetic plastid called the apicoplast, which hosts important metabolic pathways like the methylerythritol 4-phosphate (MEP) pathway that synthesizes isoprenoid precursors. Yet many details in apicoplast metabolism are not well understood. In this study, we examined the physiological roles of four glycolytic enzymes in the apicoplast of Toxoplasma gondii. Many glycolytic enzymes in T. gondii have two or more isoforms. Endogenous tagging each of these enzymes found that four of them were localized to the apicoplast, including pyruvate kinase2 (PYK2), phosphoglycerate kinase 2 (PGK2), triosephosphate isomerase 2 (TPI2) and phosphoglyceraldehyde dehydrogenase 2 (GAPDH2). The ATP generating enzymes PYK2 and PGK2 were thought to be the main energy source of the apicoplast. Surprisingly, deleting PYK2 and PGK2 individually or simultaneously did not cause major defects on parasite growth or virulence. In contrast, TPI2 and GAPDH2 are critical for tachyzoite proliferation. Conditional depletion of TPI2 caused significant reduction in the levels of MEP pathway intermediates and led to parasite growth arrest. Reconstitution of another isoprenoid precursor synthesis pathway called the mevalonate pathway in the TPI2 depletion mutant partially rescued its growth defects. Similarly, knocking down the GAPDH2 enzyme that produces NADPH also reduced isoprenoid precursor synthesis through the MEP pathway and inhibited parasite proliferation. In addition, it reduced de novo fatty acid synthesis in the apicoplast. Together, these data suggest a model that the apicoplast dwelling TPI2 provides carbon source for the synthesis of isoprenoid precursor, whereas GAPDH2 supplies reducing power for pathways like MEP, fatty acid synthesis and ferredoxin redox system in T. gondii. As such, both enzymes are critical for parasite growth and serve as potential targets for anti-toxoplasmic intervention designs. On the other hand, the dispensability of PYK2 and PGK2 suggest additional sources for energy in the apicoplast, which deserves further investigation.
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Affiliation(s)
- Zhipeng Niu
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei Province, PR China
| | - Shu Ye
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei Province, PR China
| | - Jiaojiao Liu
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei Province, PR China
| | - Mengyu Lyu
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei Province, PR China
| | - Lilan Xue
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei Province, PR China
| | - Muxiao Li
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei Province, PR China
| | - Congcong Lyu
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei Province, PR China
| | - Junlong Zhao
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei Province, PR China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, Wuhan, Hubei Province, PR China
| | - Bang Shen
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei Province, PR China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, Wuhan, Hubei Province, PR China
- Hubei Hongshan Laboratory, Wuhan, Hubei Province, PR China
- Shenzhen Institute of Nutrition and Health, Huazhong Agricultural University, Shenzhen, Guangdong Province, PR China
- Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, Guangdong Province, PR China
- * E-mail:
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In vitro cultivation methods for coccidian parasite research. Int J Parasitol 2022:S0020-7519(22)00153-9. [DOI: 10.1016/j.ijpara.2022.10.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 09/29/2022] [Accepted: 10/09/2022] [Indexed: 11/17/2022]
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Griffith MB, Pearce CS, Heaslip AT. Dense granule biogenesis, secretion, and function in Toxoplasma gondii. J Eukaryot Microbiol 2022; 69:e12904. [PMID: 35302693 PMCID: PMC9482668 DOI: 10.1111/jeu.12904] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Toxoplasma gondii is an obligate intracellular parasite and the causative agent of Toxoplasmosis. A key to understanding and treating the disease lies with determining how the parasite can survive and replicate within cells of its host. Proteins released from specialized secretory vesicles, named the dense granules (DGs), have diverse functions that are critical for adapting the intracellular environment, and are thus key to survival and pathogenicity. In this review, we describe the current understanding and outstanding questions regarding dense granule biogenesis, trafficking, and regulation of secretion. In addition, we provide an overview of dense granule protein ("GRA") function upon secretion, with a focus on proteins that have recently been identified.
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Affiliation(s)
- Michael B Griffith
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, Connecticut, USA
| | - Camille S Pearce
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, Connecticut, USA
| | - Aoife T Heaslip
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, Connecticut, USA
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Zhang Y, Li D, Lu S, Zheng B. Toxoplasmosis vaccines: what we have and where to go? NPJ Vaccines 2022; 7:131. [PMID: 36310233 PMCID: PMC9618413 DOI: 10.1038/s41541-022-00563-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2022] [Accepted: 10/17/2022] [Indexed: 11/16/2022] Open
Abstract
Despite recent major advances in developing effective vaccines against toxoplasmosis, finding new protective vaccination strategies remains a challenging and elusive goal as it is critical to prevent the disease. Over the past few years, various experimental approaches have shown that developing an effective vaccine against T. gondii is achievable. However, more remains unknown due to its complicated life cycle, difficulties in clinical translation, and lack of a standardized platform. This minireview summarizes the recent advances in the development of T. gondii vaccines and the main obstacles to developing a safe, effective and durable T. gondii vaccine. The successes and failures in developing and testing vaccine candidates for the T. gondii vaccine are also discussed, which may facilitate the future development of T. gondii vaccines.
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Affiliation(s)
- Yizhuo Zhang
- grid.506977.a0000 0004 1757 7957Institute of Parasitic Diseases, School of Basic Medicine and Forensics, Hangzhou Medical College, Hangzhou, China ,grid.506977.a0000 0004 1757 7957Engineering Research Center of Novel Vaccine of Zhejiang Province, Hangzhou Medical College, Hangzhou, China
| | - Dan Li
- grid.506977.a0000 0004 1757 7957Institute of Parasitic Diseases, School of Basic Medicine and Forensics, Hangzhou Medical College, Hangzhou, China ,grid.506977.a0000 0004 1757 7957Engineering Research Center of Novel Vaccine of Zhejiang Province, Hangzhou Medical College, Hangzhou, China
| | - Shaohong Lu
- grid.506977.a0000 0004 1757 7957Institute of Parasitic Diseases, School of Basic Medicine and Forensics, Hangzhou Medical College, Hangzhou, China ,grid.506977.a0000 0004 1757 7957Engineering Research Center of Novel Vaccine of Zhejiang Province, Hangzhou Medical College, Hangzhou, China ,grid.506977.a0000 0004 1757 7957Key Laboratory of Bio-tech Vaccine of Zhejiang Province, Hangzhou Medical College, Hangzhou, China
| | - Bin Zheng
- grid.506977.a0000 0004 1757 7957Institute of Parasitic Diseases, School of Basic Medicine and Forensics, Hangzhou Medical College, Hangzhou, China ,grid.506977.a0000 0004 1757 7957Engineering Research Center of Novel Vaccine of Zhejiang Province, Hangzhou Medical College, Hangzhou, China ,grid.506977.a0000 0004 1757 7957Key Laboratory of Bio-tech Vaccine of Zhejiang Province, Hangzhou Medical College, Hangzhou, China
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Cui J, Yang X, Yang J, Jia R, Feng Y, Shen B. A Coccidia-Specific Phosphate Transporter Is Essential for the Growth of Toxoplasma gondii Parasites. Microbiol Spectr 2022; 10:e0218622. [PMID: 36094254 PMCID: PMC9604053 DOI: 10.1128/spectrum.02186-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Accepted: 08/26/2022] [Indexed: 12/31/2022] Open
Abstract
Toxoplasma gondii is an obligate intracellular parasite that acquires all necessary nutrients from the hosts, but the exact nutrient acquisition mechanisms are poorly understood. Here, we identified three putative phosphate transporters in T. gondii. TgPiT and TgPT2 are mainly on the plasma membrane, whereas TgmPT is localized to the mitochondrion. TgPiT and TgmPT are widely present and conserved in apicomplexan parasites that include Plasmodium and Eimeria species. Nonetheless, they are dispensable for the growth and virulence of Toxoplasma. TgPT2, on the other hand, is restricted to coccidia parasites and is essential for Toxoplasma survival. TgPT2 depletion led to reduced motility and invasion, as well as growth arrest of the parasites both in vitro and in vivo. Both TgPiT and TgPT2 have phosphate transport activities and contribute to parasites' inorganic phosphate (Pi) absorption. Interestingly, the Pi importing activity of Toxoplasma parasites could be competitively inhibited by ATP and AMP. Furthermore, direct uptake of 32P-ATP was also observed, indicating the parasites' ability to scavenge host ATP. Nonetheless, ATP/AMP import is not mediated by TgPiT or TgPT2, suggesting additional mechanisms. Together, these results show the complex pathways of phosphate transport in Toxoplasma, and TgPT2 is a potential target for antitoxoplasmic intervention design due to its essential role in parasite growth. IMPORTANCE To grow and survive within host cells, Toxoplasma must scavenge necessary nutrients from hosts to support its parasitism. Transporters located in the plasma membrane of the parasites play critical roles in nutrient acquisition. Toxoplasma encodes a large number of transporters, but so far, only a few have been characterized. In this study, we identified two phosphate transporters, TgPiT and TgPT2, to localize to the plasma membrane of Toxoplasma. Although both TgPiT and TgPT2 possess phosphate transport activities, only the novel transporter TgPT2 was essential for parasite growth, both in vitro and in vivo. In addition, TgPT2 and its orthologs are only present in coccidia parasites. As such, TgPT2 represents a potential target for drug design against toxoplasmosis. In addition, our data indicated that Toxoplasma can take up ATP and AMP from the environment, providing new insights into the energy metabolism of Toxoplasma.
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Affiliation(s)
- Jianmin Cui
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei Province, People’s Republic of China
- Key Laboratory of Preventive Medicine in Hubei Province, Huazhong Agricultural University, Wuhan, Hubei Province, People’s Republic of China
| | - Xuke Yang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei Province, People’s Republic of China
- Key Laboratory of Preventive Medicine in Hubei Province, Huazhong Agricultural University, Wuhan, Hubei Province, People’s Republic of China
| | - Jichao Yang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei Province, People’s Republic of China
- Key Laboratory of Preventive Medicine in Hubei Province, Huazhong Agricultural University, Wuhan, Hubei Province, People’s Republic of China
| | - Ruilian Jia
- Center for Emerging and Zoonotic Diseases, College of Veterinary Medicine, South China Agricultural University, Guangzhou, People’s Republic of China
| | - Yaoyu Feng
- Center for Emerging and Zoonotic Diseases, College of Veterinary Medicine, South China Agricultural University, Guangzhou, People’s Republic of China
| | - Bang Shen
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei Province, People’s Republic of China
- Key Laboratory of Preventive Medicine in Hubei Province, Huazhong Agricultural University, Wuhan, Hubei Province, People’s Republic of China
- Hubei Hongshan Laboratory, Wuhan, Hubei Province, People’s Republic of China
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Interferon-Inducible E3 Ligase RNF213 Facilitates Host-Protective Linear and K63-Linked Ubiquitylation of Toxoplasma gondii Parasitophorous Vacuoles. mBio 2022; 13:e0188822. [PMID: 36154443 PMCID: PMC9601232 DOI: 10.1128/mbio.01888-22] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The obligate intracellular protozoan pathogen Toxoplasma gondii infects a wide range of vertebrate hosts and frequently causes zoonotic infections in humans. Whereas infected immunocompetent individuals typically remain asymptomatic, toxoplasmosis in immunocompromised individuals can manifest as a severe, potentially lethal disease, and congenital Toxoplasma infections are associated with adverse pregnancy outcomes. The protective immune response of healthy individuals involves the production of lymphocyte-derived cytokines such as interferon gamma (IFN-γ), which elicits cell-autonomous immunity in host cells. IFN-γ-inducible antiparasitic defense programs comprise nutritional immunity, the production of noxious gases, and the ubiquitylation of the Toxoplasma-containing parasitophorous vacuole (PV). PV ubiquitylation prompts the recruitment of host defense proteins to the PV and the consequential execution of antimicrobial effector programs, which reduce parasitic burden. However, the ubiquitin E3 ligase orchestrating these events has remained unknown. Here, we demonstrate that the IFN-γ-inducible E3 ligase RNF213 translocates to Toxoplasma PVs and facilitates PV ubiquitylation in human cells. Toxoplasma PVs become decorated with linear and K63-linked ubiquitin and recruit ubiquitin adaptor proteins in a process that is RNF213 dependent but independent of the linear ubiquitin chain assembly complex (LUBAC). IFN-γ priming fails to restrict Toxoplasma growth in cells lacking RNF213 expression, thus identifying RNF213 as a potent executioner of ubiquitylation-driven antiparasitic host defense.
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36
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Maier AG, van Ooij C. The role of cholesterol in invasion and growth of malaria parasites. Front Cell Infect Microbiol 2022; 12:984049. [PMID: 36189362 PMCID: PMC9522969 DOI: 10.3389/fcimb.2022.984049] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Accepted: 08/15/2022] [Indexed: 11/24/2022] Open
Abstract
Malaria parasites are unicellular eukaryotic pathogens that develop through a complex lifecycle involving two hosts, an anopheline mosquito and a vertebrate host. Throughout this lifecycle, the parasite encounters widely differing conditions and survives in distinct ways, from an intracellular lifestyle in the vertebrate host to exclusively extracellular stages in the mosquito. Although the parasite relies on cholesterol for its growth, the parasite has an ambiguous relationship with cholesterol: cholesterol is required for invasion of host cells by the parasite, including hepatocytes and erythrocytes, and for the development of the parasites in those cells. However, the parasite is unable to produce cholesterol itself and appears to remove cholesterol actively from its own plasma membrane, thereby setting up a cholesterol gradient inside the infected host erythrocyte. Overall a picture emerges in which the parasite relies on host cholesterol and carefully controls its transport. Here, we describe the role of cholesterol at the different lifecycle stages of the parasites.
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Affiliation(s)
- Alexander G. Maier
- Research School of Biology, The Australian National University, Canberra ACT, Australia
- *Correspondence: Alexander G. Maier, ; Christiaan van Ooij,
| | - Christiaan van Ooij
- Department of Infection Biology, London School of Hygiene & Tropical Medicine, London, United Kingdom
- *Correspondence: Alexander G. Maier, ; Christiaan van Ooij,
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Dewangan PS, Beraki TG, Paiz EA, Appiah Mensah D, Chen Z, Reese ML. Divergent kinase WNG1 is regulated by phosphorylation of an atypical activation sub-domain. Biochem J 2022; 479:1877-1889. [PMID: 35938919 PMCID: PMC9555795 DOI: 10.1042/bcj20220076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 07/28/2022] [Accepted: 08/08/2022] [Indexed: 11/17/2022]
Abstract
Apicomplexan parasites like Toxoplasma gondii grow and replicate within a specialized organelle called the parasitophorous vacuole. The vacuole is decorated with parasite proteins that integrate into the membrane after trafficking through the parasite secretory system as soluble, chaperoned complexes. A regulator of this process is an atypical protein kinase called WNG1. Phosphorylation by WNG1 appears to serve as a switch for membrane integration. However, like its substrates, WNG1 is secreted from the parasite dense granules, and its activity must, therefore, be tightly regulated until the correct membrane is encountered. Here, we demonstrate that, while another member of the WNG family can adopt multiple multimeric states, WNG1 is monomeric and therefore not regulated by multimerization. Instead, we identify two phosphosites on WNG1 that are required for its kinase activity. Using a combination of in vitro biochemistry and structural modeling, we identify basic residues that are also required for WNG1 activity and appear to recognize the activating phosphosites. Among these coordinating residues are the 'HRD' Arg, which recognizes activation loop phosphorylation in canonical kinases. WNG1, however, is not phosphorylated on its activation loop, but rather on atypical phosphosites on its C-lobe. We propose a simple model in which WNG1 is activated by increasing ATP concentration above a critical threshold once the kinase traffics to the parasitophorous vacuole.
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Affiliation(s)
- Pravin S. Dewangan
- Department of Pharmacology, University of Texas, Southwestern Medical Center, Dallas, TX, U.S.A
| | - Tsebaot G. Beraki
- Department of Pharmacology, University of Texas, Southwestern Medical Center, Dallas, TX, U.S.A
| | - E. Ariana Paiz
- Department of Pharmacology, University of Texas, Southwestern Medical Center, Dallas, TX, U.S.A
| | - Delia Appiah Mensah
- Department of Pharmacology, University of Texas, Southwestern Medical Center, Dallas, TX, U.S.A
- Honors College, University of Texas at Dallas, Richardson, TX, U.S.A
| | - Zhe Chen
- Department of Biophysics, University of Texas, Southwestern Medical Center, Dallas, TX, U.S.A
| | - Michael L. Reese
- Department of Pharmacology, University of Texas, Southwestern Medical Center, Dallas, TX, U.S.A
- Department of Biochemistry, University of Texas, Southwestern Medical Center, Dallas, TX, U.S.A
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Abstract
The intracellular parasite Toxoplasma gondii adapts to diverse host cell environments within a replicative compartment that is heavily decorated by secreted proteins. In an attempt to identify novel parasite secreted proteins that influence host cell activity, we identified and characterized a transmembrane dense granule protein dubbed GRA64 (TGME49_202620). We found that GRA64 is on the parasitophorous vacuolar membrane (PVM) and is partially exposed to the host cell cytoplasm in both tachyzoite and bradyzoite parasitophorous vacuoles. Using co-immunoprecipitation and proximity-based biotinylation approaches, we demonstrated that GRA64 appears to interact with components of the host endosomal sorting complexes required for transport (ESCRT). Genetic disruption of GRA64 does not affect acute Toxoplasma virulence or encystation in mice, as observed via tissue cyst burdens in mice during chronic infection. However, ultrastructural analysis of Δgra64 tissue cysts using electron tomography revealed enlarged vesicular structures underneath the cyst membrane, suggesting a role for GRA64 in organizing the recruitment of ESCRT proteins and subsequent intracystic vesicle formation. This study uncovers a novel host-parasite interaction that contributes to an emerging paradigm in which specific host ESCRT proteins are recruited to the limiting membranes (PVMs) of tachyzoite and bradyzoite vacuoles formed during acute and chronic Toxoplasma infection. IMPORTANCE Toxoplasma gondii is a widespread foodborne parasite that causes congenital disease and life-threatening complications in immunocompromised individuals. Part of this parasite's success lies in its ability to infect diverse organisms and host cells and to persist as a latent infection within parasite-constructed structures called tissue cysts. In this study, we characterized a protein that is secreted by T. gondii into its parasitophorous vacuole during intracellular infection, which we dub GRA64. On the vacuolar membrane, this protein is exposed to the host cell cytosol and interacts with specific host ESCRT proteins. Parasites lacking the GRA64 protein exhibit ultrastructural changes in tissue cysts during chronic infection. This study lays the foundation for future studies on the mechanics and consequences of host ESCRT-parasite protein interactions.
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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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Huynh MH, Carruthers VB. Toxoplasma gondii excretion of glycolytic products is associated with acidification of the parasitophorous vacuole during parasite egress. PLoS Pathog 2022; 18:e1010139. [PMID: 35512005 PMCID: PMC9113570 DOI: 10.1371/journal.ppat.1010139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 05/17/2022] [Accepted: 03/28/2022] [Indexed: 11/19/2022] Open
Abstract
The Toxoplasma gondii lytic cycle is a repetition of host cell invasion, replication, egress, and re-invasion into the next host cell. While the molecular players involved in egress have been studied in greater detail in recent years, the signals and pathways for triggering egress from the host cell have not been fully elucidated. A perforin-like protein, PLP1, has been shown to be necessary for permeabilizing the parasitophorous vacuole (PV) membrane or exit from the host cell. In vitro studies indicated that PLP1 is most active in acidic conditions, and indirect evidence using superecliptic pHluorin indicated that the PV pH drops prior to parasite egress. Using ratiometric pHluorin, a GFP variant that responds to changes in pH with changes in its bimodal excitation spectrum peaks, allowed us to directly measure the pH in the PV prior to and during egress by live-imaging microscopy. A statistically significant change was observed in PV pH during ionomycin or zaprinast induced egress in both wild-type RH and Δplp1 vacuoles compared to DMSO-treated vacuoles. Interestingly, if parasites are chemically paralyzed, a pH drop is still observed in RH but not in Δplp1 tachyzoites. This indicates that the pH drop is dependent on the presence of PLP1 or motility. Efforts to determine transporters, exchangers, or pumps that could contribute to the drop in PV pH identified two formate-nitrite transporters (FNTs). Auxin induced conditional knockdown and knockouts of FNT1 and FNT2 reduced the levels of lactate and pyruvate released by the parasites and lead to an abatement of vacuolar acidification. While additional transporters and molecules are undoubtedly involved, we provide evidence of a definitive reduction in vacuolar pH associated with induced and natural egress and characterize two transporters that contribute to the acidification. Toxoplasma gondii is a single celled intracellular parasite that infects many different animals, and it is thought to infect up to one third of the human population. This parasite must rupture out of its replicative compartment and the host cell to spread from one cell to another. Previous studies indicated that a decrease in pH occurs within the replicative compartment near the time of parasite exit from host cells, an event termed egress. However, it remained unknown whether the decrease in pH is directly tied to egress and, if so, what is responsible for the decrease in pH. Here we used a fluorescent reporter protein to directly measure pH within the replicative compartment during parasite egress. We found that pH decreases immediately prior to parasite egress and that this decrease is linked to parasite disruption of membranes. We also identified a family of transporters that release acidic products from parasite use of glucose for energy as contributing to the decrease in pH during egress. Our findings provide new insight that connects parasite glucose metabolism to acidification of its replicative compartment during egress from infected cells.
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Affiliation(s)
- My-Hang Huynh
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, United States of America
| | - Vern B. Carruthers
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, United States of America
- * E-mail:
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Gubbels MJ, Ferguson DJP, Saha S, Romano JD, Chavan S, Primo VA, Michaud C, Coppens I, Engelberg K. Toxoplasma gondii’s Basal Complex: The Other Apicomplexan Business End Is Multifunctional. Front Cell Infect Microbiol 2022; 12:882166. [PMID: 35573773 PMCID: PMC9103881 DOI: 10.3389/fcimb.2022.882166] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 03/30/2022] [Indexed: 01/08/2023] Open
Abstract
The Apicomplexa are famously named for their apical complex, a constellation of organelles at their apical end dedicated to invasion of their host cells. In contrast, at the other end of the cell, the basal complex (BC) has been overshadowed since it is much less prominent and specific functions were not immediately obvious. However, in the past decade a staggering array of functions have been associated with the BC and strides have been made in understanding its structure. Here, these collective insights are supplemented with new data to provide an overview of the understanding of the BC in Toxoplasma gondii. The emerging picture is that the BC is a dynamic and multifunctional complex, with a series of (putative) functions. The BC has multiple roles in cell division: it is the site where building blocks are added to the cytoskeleton scaffold; it exerts a two-step stretch and constriction mechanism as contractile ring; and it is key in organelle division. Furthermore, the BC has numerous putative roles in ‘import’, such as the recycling of mother cell remnants, the acquisition of host-derived vesicles, possibly the uptake of lipids derived from the extracellular medium, and the endocytosis of micronemal proteins. The latter process ties the BC to motility, whereas an additional role in motility is conferred by Myosin C. Furthermore, the BC acts on the assembly and/or function of the intravacuolar network, which may directly or indirectly contribute to the establishment of chronic tissue cysts. Here we provide experimental support for molecules acting in several of these processes and identify several new BC proteins critical to maintaining the cytoplasmic bridge between divided parasites. However, the dispensable nature of many BC components leaves many questions unanswered regarding its function. In conclusion, the BC in T. gondii is a dynamic and multifunctional structure at the posterior end of the parasite.
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Affiliation(s)
- Marc-Jan Gubbels
- Department of Biology, Boston College, Chestnut Hill, MA, United States
- *Correspondence: Marc-Jan Gubbels, ; Klemens Engelberg,
| | - David J. P. Ferguson
- Nuffield Department of Clinical Laboratory Science, University of Oxford John Radcliffe Hospital, Oxford, United Kingdom
- Department of Biological and Medical Sciences, Faculty of Health and Life Science, Oxford Brookes University, Oxford, United Kingdom
| | - Sudeshna Saha
- Department of Biology, Boston College, Chestnut Hill, MA, United States
| | - Julia D. Romano
- Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, United States
| | - Suyog Chavan
- Department of Biology, Boston College, Chestnut Hill, MA, United States
| | - Vincent A. Primo
- Department of Biology, Boston College, Chestnut Hill, MA, United States
| | - Cynthia Michaud
- 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
| | - Klemens Engelberg
- Department of Biology, Boston College, Chestnut Hill, MA, United States
- *Correspondence: Marc-Jan Gubbels, ; Klemens Engelberg,
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RibU is an essential determinant of Listeria pathogenesis that mediates acquisition of FMN and FAD during intracellular growth. Proc Natl Acad Sci U S A 2022; 119:e2122173119. [PMID: 35316134 PMCID: PMC9060500 DOI: 10.1073/pnas.2122173119] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Riboflavin (vitamin B2) is converted into flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD), which are essential cofactors for many redox reactions across all domains of life. Listeria monocytogenes is a facultative intracellular pathogen that cannot synthesize riboflavin and must therefore obtain flavins from the host. In this study, we show that a previously identified riboflavin transporter (RibU) is essential for virulence and intracellular growth, but rather than transporting riboflavin, RibU transports FMN and FAD directly from the host cell cytosol. Mutants unable to convert riboflavin to FMN and FAD retained their capacity to grow intracellularly and were virulent, but they were unable to grow extracellularly and were thus converted from facultative to obligate intracellular pathogens. Flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD) are essential riboflavin-derived cofactors involved in a myriad of redox reactions across all forms of life. Nevertheless, the basis of flavin acquisition strategies by riboflavin auxotrophic pathogens remains poorly defined. In this study, we examined how the facultative intracellular pathogen Listeria monocytogenes, a riboflavin auxotroph, acquires flavins during infection. A L. monocytogenes mutant lacking the putative riboflavin transporter (RibU) was completely avirulent in mice but had no detectable growth defect in nutrient-rich media. However, unlike wild type, the RibU mutant was unable to grow in defined media supplemented with FMN or FAD or to replicate in macrophages starved for riboflavin. Consistent with RibU functioning to scavenge FMN and FAD inside host cells, a mutant unable to convert riboflavin to FMN or FAD retained virulence and grew in cultured macrophages and in spleens and livers of infected mice. However, this FMN- and FAD-requiring strain was unable to grow in the gallbladder or intestines, where L. monocytogenes normally grows extracellularly, suggesting that these sites do not contain sufficient flavin cofactors to promote replication. Thus, by deleting genes required to synthesize FMN and FAD, we converted L. monocytogenes from a facultative to an obligate intracellular pathogen. Collectively, these data indicate that L. monocytogenes requires riboflavin to grow extracellularly in vivo but scavenges FMN and FAD to grow in host cells.
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Shunmugam S, Arnold CS, Dass S, Katris NJ, Botté CY. The flexibility of Apicomplexa parasites in lipid metabolism. PLoS Pathog 2022; 18:e1010313. [PMID: 35298557 PMCID: PMC8929637 DOI: 10.1371/journal.ppat.1010313] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Apicomplexa are obligate intracellular parasites responsible for major human infectious diseases such as toxoplasmosis and malaria, which pose social and economic burdens around the world. To survive and propagate, these parasites need to acquire a significant number of essential biomolecules from their hosts. Among these biomolecules, lipids are a key metabolite required for parasite membrane biogenesis, signaling events, and energy storage. Parasites can either scavenge lipids from their host or synthesize them de novo in a relict plastid, the apicoplast. During their complex life cycle (sexual/asexual/dormant), Apicomplexa infect a large variety of cells and their metabolic flexibility allows them to adapt to different host environments such as low/high fat content or low/high sugar levels. In this review, we discuss the role of lipids in Apicomplexa parasites and summarize recent findings on the metabolic mechanisms in host nutrient adaptation.
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Affiliation(s)
- Serena Shunmugam
- Apicolipid Team, Institute for Advanced Biosciences, CNRS UMR5309, Université Grenoble Alpes, INSERM U1209, Grenoble, France
| | - Christophe-Sébastien Arnold
- Apicolipid Team, Institute for Advanced Biosciences, CNRS UMR5309, Université Grenoble Alpes, INSERM U1209, Grenoble, France
| | - Sheena Dass
- Apicolipid Team, Institute for Advanced Biosciences, CNRS UMR5309, Université Grenoble Alpes, INSERM U1209, Grenoble, France
| | - Nicholas J. Katris
- Apicolipid Team, Institute for Advanced Biosciences, CNRS UMR5309, Université Grenoble Alpes, INSERM U1209, Grenoble, France
| | - Cyrille Y. Botté
- Apicolipid Team, Institute for Advanced Biosciences, CNRS UMR5309, Université Grenoble Alpes, INSERM U1209, Grenoble, France
- * E-mail: ,
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Nguyen TT, Kamyingkird K, Phimpraphai W, Inpankaew T. Viability of Toxoplasma gondii tachyzoites in different conditions for parasite transportation. Vet World 2022; 15:198-204. [PMID: 35369589 PMCID: PMC8924386 DOI: 10.14202/vetworld.2022.198-204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2021] [Accepted: 12/31/2021] [Indexed: 11/20/2022] Open
Abstract
Background and Aim: Toxoplasma gondii tachyzoite is the infective stage that causes acute infection, leading to severe toxoplasmosis. The tachyzoite stage has been extensively used for several inoculation purposes, including antigen production, immunological studies, nutrition mechanisms, and in vitro drug trials. The use of fresh tachyzoites is required for inoculation in either in vitro or in vivo studies. However, there is a lack of information on preserving live tachyzoites during transportation from laboratories to inoculation sites. Therefore, this study aimed to validate suitable preservative conditions for maintaining live parasites by determining the survival and viability of T. gondii tachyzoites on the basis of different media, temperatures, and incubation times. Materials and Methods: The free live T. gondii tachyzoites were evaluated on their viability when maintained in different media without 5% Carbon dioxide (CO2). The purified tachyzoites of the RH and PLK strains were individually suspended in normal saline (NS), phosphate-buffered saline (PBS), minimum essential medium (MEM), and MEM with 10% fetal bovine serum (MEM-FBS) and incubated for 6 h at ice-cold (IC; 3-9°C) and room temperature (RT; 25°C). Parasite survival was measured at the 0, 1st, 2nd, 3rd, 4th, 5th, and 6th h post-incubation using the trypan blue exclusion test. Results: The viability was in the range of 85.0%–91.0% for IC using NS and 81.0%–85.1% (IC) and 75.3%–77.5% (RT) using PBS. The viability was approximately 75.0%–83.0% (IC) and 70.0%–79.0% (RT) using MEM and MEM-FBS. There was a significant difference in the viability between the seven periods on the basis of one-way repeated Analysis of variance and Friedman analyses. Parasite survival slightly reduced (20.0%–30.0%) in NS and MEM-FBS at both temperatures during incubation. Notably, PBS could not support tachyzoite viability after 3 h post-incubation. Conclusion: NS was a suitable preservative for maintaining purified T. gondii tachyzoites during transportation at IC and RT without 5% CO2 supplementation. This could be a valuable medium for parasite transportation, especially when there is a large distance between the laboratory and inoculation site.
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Affiliation(s)
- Thi Thuy Nguyen
- Department of Parasitology, Faculty of Veterinary Medicine, Kasetsart University, Bangkok 10900, Thailand; Department of Veterinary Medicine, Faculty of Animal Science and Veterinary Medicine, University of Agriculture and Forestry, Hue University, Hue, Vietnam
| | - Ketsarin Kamyingkird
- Department of Parasitology, Faculty of Veterinary Medicine, Kasetsart University, Bangkok 10900, Thailand
| | - Waraphon Phimpraphai
- Department of Veterinary Public Health, Faculty of Veterinary Medicine, Kasetsart University, Bangkok 10900, Thailand
| | - Tawin Inpankaew
- Department of Parasitology, Faculty of Veterinary Medicine, Kasetsart University, Bangkok 10900, Thailand
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Yan X, Han W, Jin X, Sun Y, Gao J, Yu X, Guo J. Study on the effect of koumiss on the intestinal microbiota of mice infected with Toxoplasma gondii. Sci Rep 2022; 12:1271. [PMID: 35075239 PMCID: PMC8786867 DOI: 10.1038/s41598-022-05454-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2021] [Accepted: 01/12/2022] [Indexed: 12/16/2022] Open
Abstract
Toxoplasma gondii is a worldwide food-borne parasite that can infect almost all warm-blooded animals, including humans. To date, there are no effective drugs to prevent or eradicate T. gondii infection. Recent studies have shown that probiotics could influence the relationship between the microbiota and parasites in the host. Koumiss has been used to treat many diseases based on its probiotic diversity. Therefore, we explored the effect of koumiss on T. gondii infection via its effect on the host intestinal microbiota. BALB/c mice were infected with T. gondii and treated with PBS, koumiss and mares' milk. Brain cysts were counted, and long-term changes in the microbiota and the effect of koumiss on gut microbiota were investigated with high-throughput sequencing technology. The results suggested that koumiss treatment significantly decreased the cyst counts in the brain (P < 0.05). Moreover, T. gondii infection changed the microbiota composition, and koumiss treatment increased the relative abundance of Lachnospiraceae and Akkermansia muciniphila, which were associated with preventing T. gondii infection. Moreover, koumiss could inhibit or ameliorate T. gondii infection by increasing the abundance of certain bacteria that control unique metabolic pathways. The study not only established a close interaction among the host, intracellular pathogens and intestinal microbiota but also provided a novel focus for drug development to prevent and eradicate T. gondii infection.
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Affiliation(s)
- Xinlei Yan
- Food Science and Engineering College of Inner Mongolia Agricultural University, Hohhot, 010018, China.
| | - Wenying Han
- Food Science and Engineering College of Inner Mongolia Agricultural University, Hohhot, 010018, China
| | - Xindong Jin
- Food Science and Engineering College of Inner Mongolia Agricultural University, Hohhot, 010018, China
| | - Yufei Sun
- Food Science and Engineering College of Inner Mongolia Agricultural University, Hohhot, 010018, China
| | - Jialu Gao
- Food Science and Engineering College of Inner Mongolia Agricultural University, Hohhot, 010018, China
| | - Xiuli Yu
- Food Science and Engineering College of Inner Mongolia Agricultural University, Hohhot, 010018, China
| | - Jun Guo
- Food Science and Engineering College of Inner Mongolia Agricultural University, Hohhot, 010018, China.
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An Uninvited Seat at the Dinner Table: How Apicomplexan Parasites Scavenge Nutrients from the Host. Microorganisms 2021; 9:microorganisms9122592. [PMID: 34946193 PMCID: PMC8707601 DOI: 10.3390/microorganisms9122592] [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: 11/16/2021] [Revised: 12/10/2021] [Accepted: 12/13/2021] [Indexed: 12/24/2022] Open
Abstract
Obligate intracellular parasites have evolved a remarkable assortment of strategies to scavenge nutrients from the host cells they parasitize. Most apicomplexans form a parasitophorous vacuole (PV) within the invaded cell, a replicative niche within which they survive and multiply. As well as providing a physical barrier against host cell defense mechanisms, the PV membrane (PVM) is also an important site of nutrient uptake that is essential for the parasites to sustain their metabolism. This means nutrients in the extracellular milieu are separated from parasite metabolic machinery by three different membranes, the host plasma membrane, the PVM, and the parasite plasma membrane (PPM). In order to facilitate nutrient transport from the extracellular environment into the parasite itself, transporters on the host cell membrane of invaded cells can be modified by secreted and exported parasite proteins to maximize uptake of key substrates to meet their metabolic demand. To overcome the second barrier, the PVM, apicomplexan parasites secrete proteins contained in the dense granules that remodel the vacuole and make the membrane permissive to important nutrients. This bulk flow of host nutrients is followed by a more selective uptake of substrates at the PPM that is operated by specific transporters of this third barrier. In this review, we recapitulate and compare the strategies developed by Apicomplexa to scavenge nutrients from their hosts, with particular emphasis on transporters at the parasite plasma membrane and vacuolar solute transporters on the parasite intracellular digestive organelle.
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Abstract
Toxoplasma gondii is a parasitic protist infecting a wide group of warm-blooded animals, ranging from birds to humans. While this infection is usually asymptomatic in healthy individuals, it can also lead to severe ocular or neurological outcomes in immunocompromised individuals or in developing fetuses. This obligate intracellular parasite has the ability to infect a considerable range of nucleated cells and can propagate in the intermediate host. Yet, under the pressure of the immune system it transforms into an encysted persistent form residing primarily in the brain and muscle tissues. Encysted parasites, which are resistant to current medication, may reactivate and give rise to an acute infection. The clinical outcome of toxoplasmosis depends on a complex balance between the host immune response and parasite virulence factors. Susceptibility to the disease is thus determined by both parasite strains and host species. Recent advances on our understanding of host cell-parasite interactions and parasite virulence have brought new insights into the pathophysiology of T. gondii infection and are summarized here.
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48
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Sloan MA, Aghabi D, Harding CR. Orchestrating a heist: uptake and storage of metals by apicomplexan parasites. MICROBIOLOGY (READING, ENGLAND) 2021; 167. [PMID: 34898419 PMCID: PMC7612242 DOI: 10.1099/mic.0.001114] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Megan A Sloan
- Wellcome Centre for Integrative Parasitology, Institute for Infection, Immunity and Inflammation, University of Glasgow, UK
| | - Dana Aghabi
- Wellcome Centre for Integrative Parasitology, Institute for Infection, Immunity and Inflammation, University of Glasgow, UK
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Dumaine JE, Sateriale A, Gibson AR, Reddy AG, Gullicksrud JA, Hunter EN, Clark JT, Striepen B. The enteric pathogen Cryptosporidium parvum exports proteins into the cytosol of the infected host cell. eLife 2021; 10:70451. [PMID: 34866573 PMCID: PMC8687662 DOI: 10.7554/elife.70451] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Accepted: 11/19/2021] [Indexed: 12/11/2022] Open
Abstract
The parasite Cryptosporidium is responsible for diarrheal disease in young children causing death, malnutrition, and growth delay. Cryptosporidium invades enterocytes where it develops in a unique intracellular niche. Infected cells exhibit profound changes in morphology, physiology, and transcriptional activity. How the parasite effects these changes is poorly understood. We explored the localization of highly polymorphic proteins and found members of the Cryptosporidium parvum MEDLE protein family to be translocated into the cytosol of infected cells. All intracellular life stages engage in this export, which occurs after completion of invasion. Mutational studies defined an N-terminal host-targeting motif and demonstrated proteolytic processing at a specific leucine residue. Direct expression of MEDLE2 in mammalian cells triggered an ER stress response, which was also observed during infection. Taken together, our studies reveal the presence of a Cryptosporidium secretion system capable of delivering parasite proteins into the infected enterocyte.
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Affiliation(s)
- Jennifer E Dumaine
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, United States
| | - Adam Sateriale
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, United States
| | - Alexis R Gibson
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, United States
| | - Amita G Reddy
- Franklin College of Arts and Science, University of Georgia, Athens, United States
| | - Jodi A Gullicksrud
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, United States
| | - Emma N Hunter
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, United States
| | - Joseph T Clark
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, United States
| | - Boris Striepen
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, United States
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50
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de Vries LE, Lunghi M, Krishnan A, Kooij TWA, Soldati-Favre D. Pantothenate and CoA biosynthesis in Apicomplexa and their promise as antiparasitic drug targets. PLoS Pathog 2021; 17:e1010124. [PMID: 34969059 PMCID: PMC8717973 DOI: 10.1371/journal.ppat.1010124] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The Apicomplexa phylum comprises thousands of distinct intracellular parasite species, including coccidians, haemosporidians, piroplasms, and cryptosporidia. These parasites are characterized by complex and divergent life cycles occupying a variety of host niches. Consequently, they exhibit distinct adaptations to the differences in nutritional availabilities, either relying on biosynthetic pathways or by salvaging metabolites from their host. Pantothenate (Pan, vitamin B5) is the precursor for the synthesis of an essential cofactor, coenzyme A (CoA), but among the apicomplexans, only the coccidian subgroup has the ability to synthesize Pan. While the pathway to synthesize CoA from Pan is largely conserved across all branches of life, there are differences in the redundancy of enzymes and possible alternative pathways to generate CoA from Pan. Impeding the scavenge of Pan and synthesis of Pan and CoA have been long recognized as potential targets for antimicrobial drug development, but in order to fully exploit these critical pathways, it is important to understand such differences. Recently, a potent class of pantothenamides (PanAms), Pan analogs, which target CoA-utilizing enzymes, has entered antimalarial preclinical development. The potential of PanAms to target multiple downstream pathways make them a promising compound class as broad antiparasitic drugs against other apicomplexans. In this review, we summarize the recent advances in understanding the Pan and CoA biosynthesis pathways, and the suitability of these pathways as drug targets in Apicomplexa, with a particular focus on the cyst-forming coccidian, Toxoplasma gondii, and the haemosporidian, Plasmodium falciparum.
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Affiliation(s)
- Laura E. de Vries
- Department of Medical Microbiology, Radboudumc Center for Infectious Diseases, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Matteo Lunghi
- Department of Microbiology & Molecular Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Aarti Krishnan
- Department of Microbiology & Molecular Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Taco W. A. Kooij
- Department of Medical Microbiology, Radboudumc Center for Infectious Diseases, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Dominique Soldati-Favre
- Department of Microbiology & Molecular Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland
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