In vitro growth of Toxoplasma gondii tachyzoites on different host cell lines selects for changes in efficiency of invasion and parasite surface antigen gene expression
Ontology highlight
ABSTRACT:
ORGANISM(S): Toxoplasma gondii ME49
PROVIDER: GSE300509 | GEO | 2026/02/25
REPOSITORIES: GEO
Similar Datasets
Project description:The lytic cycle of the protozoan parasite Toxoplasma gondii, which involves a brief sojourn in the extracellular space, is characterized by defined transcriptional profiles. For an obligate intracellular parasite that is shielded from the cytosolic host immune factors by a parasitophorous vacuole, the brief entry into the extracellular space is likely to exert enormous stress. Due to its role in cellular stress response, we hypothesize that translational control plays an important role in regulating gene expression in Toxoplasma during the lytic cycle. Unlike transcriptional profiles, insights into genome-wide translational profiles of Toxoplasma gondii are lacking. We have performed genome-wide ribosome profiling, coupled with high throughput RNA sequencing, in intracellular and extracellular Toxoplasma gondii parasites to investigate translational control during the lytic cycle. Results: Although differences in transcript abundance were mostly mirrored at the translational level, we observed significant differences in the abundance of ribosome footprints between the two parasite stages. Furthermore, our data suggest that mRNA translation in the parasite is potentially regulated by mRNA secondary structure and upstream open reading frames.
2017-11-23 | GSE99395 | GEO
Project description:To identify accessible chromatin regions in the human host cells during Toxoplasma parasite infection (uninfected, RH-infected and Pru-infected human foreskin fibroblasts) and in the obligate intracellular parasite Toxoplasma gondii (Type 1 RH strain and Type 2 Pru strain), ATAC-seq was performed.
2022-09-30 | GSE209866 | GEO
Project description:Toxoplasma gondii is an obligate intracellular Apicomplexan parasite capable of invading and surviving within nucleated cells in most warm-blooded animals. This remarkable task is achieved through the delivery of effector proteins from the parasite into the parasitophorous vacuole and host cell cytosol that rewire host cellular pathways, facilitating parasite evasion of the immune system. Here, we have identified a novel export pathway in Toxoplasma that involves cleavage of effector proteins by the Golgi-resident aspartyl protease 5 (ASP5) prior to translocation into the host cell. We demonstrate that ASP5 cleaves a highly constrained amino acid motif that has some similarity to the PEXEL motif of Plasmodium parasites. We show that ASP5 can mature effectors at both the N- and C-terminal ends of proteins and is also required for the trafficking of proteins without this motif. Furthermore, we show that ASP5 controls establishment of the nanotubular network and is required for the efficient recruitment of host mitochondria to the parasitophorous vacuole membrane. Global assessment of host gene expression following infection reveals that ASP5-dependent pathways influence thousands of the transcriptional changes that Toxoplasma imparts on its host cell. This work characterizes the first identified machinery required for export of Toxoplasma effectors into the infected host cell. Three groups of human foreskin fibroblasts are compared. Each group has 3 replicates giving a total of 9 samples. The first group of samples are infected with wild type (GRA16HA) Toxoplasma gondii, the second group with Asp5 knock-out Toxoplasma gondii, and the final group remain uninfected. All fibroblasts are generated from one donor sample.
2015-11-19 | E-GEOD-73986 | biostudies-arrayexpress
Project description:Toxoplasma gondii is a ubiquitous protozoan pathogen able to infect both mammalian and avian hosts. Surprisingly, just three strains appear to account for the majority of isolates from Europe and N. America. To test the hypothesis that strain divergence might be driven by differences between mammalian and avian response to infection, we examine in vitro strain-dependent host responses in a representative avian host, the chicken. To identify parasite drivers of strain-dependent host response, QTL mapping was used; analysis revealed a locus on Toxoplasma chromosome VIIb. To determine whether this was the parasite gene ROP16, array analysis was performed on chicken embryonic fibroblasts infected with Type I parasites and ROP16-KO parasites (of a Type I background).
2011-05-27 | GSE29564 | GEO
Project description:Toxoplasma gondii, the causative agent of toxoplasmosis, infects roughly one-third of the global population, highlighting its remarkable adaptability and pathogenicity across a wide range of warm-blooded animals. A key aspect of T. gondii’s ability to interact with its hosts involves the secretion of extracellular vesicles (EVs), which play a crucial role in mediating host-parasite interactions. These EVs carry a variety of molecular cargoes, including proteins, lipids, and RNA, which can alter host cellular responses and promote parasite survival. This project focuses on understanding how T. gondii adapts its EVs to the host environment. To explore this, we analyzed the EV cargo of T. gondii cultured in four different host cell lines representing distinct species. Each cell type provides a unique environment that mimics the conditions encountered by T. gondii during infection. By comparing the EV compositions across these cell lines, we aim to identify the diverse adaptive strategies that T. gondii employs through its EVs. Using liquid chromatography-tandem mass spectrometry (LC-MS/MS), we characterized the EVs and conducted a comprehensive quantitative analysis of their proteomic cargo. Our findings revealed notable differences in the abundance and composition of EVs produced by tachyzoites cultivated in distinct host environments, underscoring the significant influence of host cell type on the makeup of T. gondii EVs.
2025-03-19 | PXD055601 | Pride
Project description:The closely related protozoan parasites Toxoplasma gondii and Neospora caninum display similar life cycles, subcellular ultrastructure, invasion mechanisms, metabolic pathways, and genome organization, but differ in their host range and disease pathogenesis. Type II (γ) interferon has long been known to be the major mediator of innate and adaptive immunity to Toxoplasma infection, but genome-wide expression profiling of infected host cells indicates that Neospora is a potent activator of the type I (α/β) interferon pathways typically associated with antiviral responses. Infection of macrophages from mice with targeted deletions in various innate sensing genes demonstrates that host responses to Neospora are dependent on the toll-like receptor Tlr3 and the adapter protein Trif. Consistent with this observation, RNA from Neospora elicits type I interferon responses when targeted to the host endo-lysosomal system. While live Toxoplasma fails to induce type I interferon, heat-killed parasites do trigger this response, and co-infection studies reveal that T. gondii actively suppresses the production of type I interferon. These findings reveal that eukaryotic pathogens can be potent inducers of type I interferon and that some parasite species, like Toxoplasma gondii, have evolved mechanisms to suppress this response. Human foreskin fibroblasts (HFF; line BJ-5ta) were cultured to confluency in T25 flasks, infected with one representative of each of the three architypial strains of Toxoplasma gondii: GT1 (type I), Prugniaud (type II) and VEG (type III), or the closely related parasite species, Neospora caninum (strain Nc-Liv). RNA was collected from biological replicates for expression profiling by microarray. Uninfected HFF cells were used as a reference.
2013-03-29 | E-GEOD-45633 | biostudies-arrayexpress
Project description:The outcome of infections with Toxoplasma gondii in humans is dependent in part on the genetic makeup of the infecting organism. Recent studies have indicated that most infecting Toxoplasma organisms fall into 1 of 3 canonical lineages. Previous studies have investigated the effects of Toxoplasma on its host cell transcriptome. Little is known, however, about the effects of three canonical lineages on brain cells, the principal site of parasite lifelong persistence. In this study, we examined the transcriptional profile of human neuroepithelioma cells in response to T. gondii infection using microarray analysis to characterize the strain-specific host cell response to 3 canonical T. gondii strains. We found that the extent of the expression changes varied considerably among the three strains. Neuroepithelial cells infected with type I exhibited the most differential gene expression, whereas type II infected cells had a substantially smaller number of genes which were differentially expressed. Cells infected with type III exhibited intermediate effects on gene expression. The three strains also differed in the individual genes and gene pathways which were altered following cellular infection. For example, gene ontology (GO) analysis indicated that type I infection largely affects genes related to central nervous system while type III infection largely alters genes which affect nucleotide metabolism; type II infection does not alter expression of a clearly defined set of genes. Moreover, Ingenuity pathway analysis (IPA) revealed the sophistication of different strain in its interactions with the host. These differences may explain some of the variation in the neurobiological effects of different strains of Toxoplasma on infected individuals. We infected SK-N-MC cells with 3 canonical Toxoplasma strains and assessed their gene expression in RNA at 20 hours post-infection using Affymetrix GeneChip. Infections and controls (no tachyzoites) were performed in duplicate and experiments for each strain were carried out on three separate occasions in order to include both technical replicates and biological replicates.
2011-06-24 | E-GEOD-22986 | biostudies-arrayexpress
Project description:Toxoplasma gondii is an obligate intracellular parasite which can cause toxoplasmosis. Surface and secreted proteins of T. gondii play important roles in infection and immunity, and also are antigen targets in immunological diagnosis and vaccine development. However, it is difficult to investigate identities and antigenicities of surface and secreted proteins due to limitation of surface protein extraction methods. In this study, a total of 785 potential surface and secreted proteins of T. gondii RH tachyzoites were identified using a method combination of biotin labeling, avidin chromatography isolation, and high flux proteomics (LC-MS/MS). Among the highly-expressed 65 proteins, 43 proteins (66%) were originally annotated as surface or secreted proteins in the released T. gondii genomes, which proved the method combination to be a credible strategy. Furthermore, the transcriptomic responses and cytokine secretions induced by the isolated proteins, the live T. gondii RH tachyzoites infection, and the live pathogenic E. coli infection, in the human peripheral blood monocyte THP-1 cell lines, were comparatively analyzed to reveal antigenicities and immunobiological properties of T. gondii surface and secreted proteins. The transciptomic profiles induced by the isolated proteins were similar to those induced by the live bacterium infection, but were different from those induced by the live parasite infection. Contrary to the low cytokine secretion induced by the live parasite infection, the isolated proteins induced significant cytokine and chemokines secretion. Especially, the secretions of several chemokines induced by the isolated proteins were even higher than those induced by the live bacterium infection. These data suggested that T. gondii surface and secreted proteins were effective antigens, while the live parasite could evade the host innate immunity. This study comprehensively revealed the identities and antigenicities of T. gondii surface and secreted proteins, which laid foundation for further screening new T. gondii antigens, developing immunological diagnosis methods, and studying host immune response to T. gondii infection.
2017-09-20 | GSE103985 | GEO
Project description:Tymoshenko2015 - Genome scale metabolic model
- ToxoNet1
This model is described in the article:
Metabolic Needs and
Capabilities of Toxoplasma gondii through Combined
Computational and Experimental Analysis.
Tymoshenko S, Oppenheim RD, Agren R,
Nielsen J, Soldati-Favre D, Hatzimanikatis V.
PLoS Comput. Biol. 2015 May; 11(5):
e1004261
Abstract:
Toxoplasma gondii is a human pathogen prevalent worldwide
that poses a challenging and unmet need for novel treatment of
toxoplasmosis. Using a semi-automated reconstruction algorithm,
we reconstructed a genome-scale metabolic model, ToxoNet1. The
reconstruction process and flux-balance analysis of the model
offer a systematic overview of the metabolic capabilities of
this parasite. Using ToxoNet1 we have identified significant
gaps in the current knowledge of Toxoplasma metabolic pathways
and have clarified its minimal nutritional requirements for
replication. By probing the model via metabolic tasks, we have
further defined sets of alternative precursors necessary for
parasite growth. Within a human host cell environment, ToxoNet1
predicts a minimal set of 53 enzyme-coding genes and 76
reactions to be essential for parasite replication.
Double-gene-essentiality analysis identified 20 pairs of genes
for which simultaneous deletion is deleterious. To validate
several predictions of ToxoNet1 we have performed experimental
analyses of cytosolic acetyl-CoA biosynthesis. ATP-citrate
lyase and acetyl-CoA synthase were localised and their
corresponding genes disrupted, establishing that each of these
enzymes is dispensable for the growth of T. gondii, however
together they make a synthetic lethal pair.
This model is hosted on
BioModels Database
and identified by:
MODEL1504280000.
To cite BioModels Database, please use:
BioModels Database:
An enhanced, curated and annotated resource for published
quantitative kinetic models.
To the extent possible under law, all copyright and related or
neighbouring rights to this encoded model have been dedicated to
the public domain worldwide. Please refer to
CC0
Public Domain Dedication for more information.
2015-07-07 | MODEL1504280000 | BioModels
Project description:The outcome of infections with Toxoplasma gondii in humans is dependent in part on the genetic makeup of the infecting organism. Recent studies have indicated that most infecting Toxoplasma organisms fall into 1 of 3 canonical lineages. Previous studies have investigated the effects of Toxoplasma on its host cell transcriptome. Little is known, however, about the effects of three canonical lineages on brain cells, the principal site of parasite lifelong persistence. In this study, we examined the transcriptional profile of human neuroepithelioma cells in response to T. gondii infection using microarray analysis to characterize the strain-specific host cell response to 3 canonical T. gondii strains. We found that the extent of the expression changes varied considerably among the three strains. Neuroepithelial cells infected with type I exhibited the most differential gene expression, whereas type II infected cells had a substantially smaller number of genes which were differentially expressed. Cells infected with type III exhibited intermediate effects on gene expression. The three strains also differed in the individual genes and gene pathways which were altered following cellular infection. For example, gene ontology (GO) analysis indicated that type I infection largely affects genes related to central nervous system while type III infection largely alters genes which affect nucleotide metabolism; type II infection does not alter expression of a clearly defined set of genes. Moreover, Ingenuity pathway analysis (IPA) revealed the sophistication of different strain in its interactions with the host. These differences may explain some of the variation in the neurobiological effects of different strains of Toxoplasma on infected individuals.
2011-06-24 | GSE22986 | GEO