Effect of AP2IX-9 overexpression on CTG transcriptome upon alkaline treatment
Ontology highlight
ABSTRACT:
ORGANISM(S): Toxoplasma gondii
PROVIDER: GSE36300 | GEO | 2013/01/01
SECONDARY ACCESSION(S): PRJNA153041
REPOSITORIES: GEO
Similar Datasets
Project description:Overexpression of DDHA-AP2IX-9 under a tubulin promoter in type III CTG strain. Differential expression analysis under addition of shield-1 and comparison to the non-bradyzoite induced parental culture revealed a global downregulation of the bradyzoite gene expression program including canonical markers like BAG1. 11 samples total. Each conditions in duplicates except wildtype CTG under tachyzoite condition in triplicates.
2013-01-01 | E-GEOD-36300 | biostudies-arrayexpress
Project description:Using high through-put RNA sequencing, we assayed the transcriptomes of three different strains of Toxoplasma gondii representing three common genotypes under both in vitro tachyzoite and in vitro bradyzoite-inducing alkaline stress culture conditions. Strikingly, the differences in transcriptional profiles between the strains, RH, PLK, and CTG, is much greater than differences between tachyzoites and alkaline stressed in vitro bradyzoites. With an FDR of 10%, we identify 241 genes differentially expressed between CTG tachyzoites and in vitro bradyzoites, including 5 putative AP2 transcription factors. We also observe close association between cell cycle regulated genes and differentiation. By Gene Set Enrichment Analysis (GSEA), there are a number of KEGG pathways associated with the in vitro bradyzoite transcriptomes of PLK and CTG, including pyrimidine metabolism and DNA replication. These functions are likely associated with cell-cycle arrest. When comparing mRNA levels between strains, we identify 1,526 genes that are differentially expressed regardless of culture-condition as well as 846 differentially expressed only in bradyzoites and 542 differentially expressed only in tachyzoites between at least two strains. Using GSEA, we identify ribosomal proteins as being expressed at significantly higher levels in the CTG strain than in either the RH or PLK strains. This association holds true regardless of life cycle stage. Type I M-bM-^@M-^S RH, Type II M-bM-^@M-^S PLK, and Type III CTG parasites were each grown in either alkaline, bradyzoite conditions or pH neutral, tachyzoites conditions. 6 conditions, 3 replicates each, 18 total samples
2014-09-01 | E-GEOD-60305 | biostudies-arrayexpress
Project description:Analysis of TgAP2IV-3 overexpression (pH7.0, pH7.8) and knockout parasites(ph8.2) in the developmental CTG (Type III) genetic background, in vitro, 32-48hrs The role for TgAP2IV-3 was evaluated in the overexpression system of ddFKBP(DD) fusion protein with a-tubulin promotor controlled by Shield 1 (100nM)
2016-11-03 | GSE89469 | GEO
Project description:Using high through-put RNA sequencing, we assayed the transcriptomes of three different strains of Toxoplasma gondii representing three common genotypes under both in vitro tachyzoite and in vitro bradyzoite-inducing alkaline stress culture conditions. Strikingly, the differences in transcriptional profiles between the strains, RH, PLK, and CTG, is much greater than differences between tachyzoites and alkaline stressed in vitro bradyzoites. With an FDR of 10%, we identify 241 genes differentially expressed between CTG tachyzoites and in vitro bradyzoites, including 5 putative AP2 transcription factors. We also observe close association between cell cycle regulated genes and differentiation. By Gene Set Enrichment Analysis (GSEA), there are a number of KEGG pathways associated with the in vitro bradyzoite transcriptomes of PLK and CTG, including pyrimidine metabolism and DNA replication. These functions are likely associated with cell-cycle arrest. When comparing mRNA levels between strains, we identify 1,526 genes that are differentially expressed regardless of culture-condition as well as 846 differentially expressed only in bradyzoites and 542 differentially expressed only in tachyzoites between at least two strains. Using GSEA, we identify ribosomal proteins as being expressed at significantly higher levels in the CTG strain than in either the RH or PLK strains. This association holds true regardless of life cycle stage.
2014-09-01 | GSE60305 | GEO
Project description:Expanded CAG/CTG repeats underlie thirteen neurological disorders, including myotonic dystrophy type 1 (DM1) and Huntington’s disease (HD). Upon expansion, CAG/CTG repeat loci acquire heterochromatic characteristics. This observation raises the hypothesis that repeat expansion provokes changes to higher-order chromatin conformation and thereby affects both gene expression in cis and the genetic instability of the repeat tract. Here we tested this hypothesis directly by performing 4C sequencing at the DMPK and HTT loci from DM1 and HD patient-derived cells. Surprisingly, chromatin contacts remain unchanged upon repeat expansion at both loci. This was true for expanded alleles with different DNA methylation levels and CTCF binding. Repeat tract sizes ranging from 15 to 1,700 repeats displayed strikingly similar chromatin interaction profiles. Moreover, the ectopic insertion of an expanded CAG repeat tract did not change the three-dimensional chromatin conformation of the surrounding genomic region. Our findings argue that extensive changes in heterochromatic properties are not enough to alter chromatin conformation at expanded CAG/CTG repeat loci. We conclude that 3D chromatin conformation is unlikely to drive repeat expansions or changes in gene expression in expanded CAG/CTG repeat disorders. This SuperSeries is composed of the SubSeries listed below.
2020-04-07 | GSE148185 | GEO
Project description:Previous studies suggested that specific bradyzoite genes were differentially expressed in the three major lineages common to North America and Europe (Radke et al., 2006). In order to determine if these differences extended to the global transcriptome, we characterized whole-cell mRNA levels in both tachyzoite and bradyzoite populations from three primary strain isolates differentiated in vitro. It is well understood in the field that long passage history is associated with the loss of developmental competence (Frenkel et al., 1976). Therefore, the Type I-GT1, Type II-Me49B7 and Type III-CTG strains studied here were maintained at < 20 cell culture passages from the oocyst stage and are capable of completing both intermediate and definitive host life cycles. These experiments used newly constructed Affymetrix GeneChips that include probe sets for ~8000 genes, and we assessed the induction of bradyzoite genes using a strong inducer of bradyzoite differentiation, Compound 1 (Radke et al., 2006). Both tachyzoite and induced (Compound 1/48hrs - bradyzoite) RNA for strains representing the three major lineages of Toxoplasma gondii were hybridized .
2010-05-19 | E-GEOD-16037 | biostudies-arrayexpress
Project description:Two forms of the protozoan parasite Toxoplasma gondii are associated with intermediate hosts such as humans: rapidly growing tachyzoites are responsible for acute illness, whereas slowly dividing encysted bradyzoites can remain latent within the tissues for the life of the host. In order to identify genetic factors associated with parasite differentiation, we have used a strong bradyzoite-specific promoter (identified by promoter trapping) to drive the expression of T. gondii hypoxanthine-xanthine-guanine phosphoribosyltransferase (HXGPRT) in stable transgenic parasites, providing a stage-specific positive/negative selectable marker. Insertional mutagenesis has been carried out on this parental line, followed by bradyzoite induction in vitro and selection in 6-thioxanthine to identify misregulation mutants. Two different mutants fail to induce the HXGPRT gene efficiently during bradyzoite differentiation. These mutants are also defective in other aspects of differentiation: they replicate well under bradyzoite growth conditions, lysing the host cell monolayer as effectively as tachyzoites. Expression of the major bradyzoite antigen BAG1 is reduced, and staining with Dolichos biflorus lectin shows reduced cyst wall formation. Microarray hybridizations show that these mutants behave more like tachyzoites at a global level, even under bradyzoite differentiation conditions.
2005-07-21 | E-SMDB-1406 | biostudies-arrayexpress
Project description:Previous studies suggested that specific bradyzoite genes were differentially expressed in the three major lineages common to North America and Europe (Radke et al., 2006). In order to determine if these differences extended to the global transcriptome, we characterized whole-cell mRNA levels in both tachyzoite and bradyzoite populations from three primary strain isolates differentiated in vitro. It is well understood in the field that long passage history is associated with the loss of developmental competence (Frenkel et al., 1976). Therefore, the Type I-GT1, Type II-Me49B7 and Type III-CTG strains studied here were maintained at < 20 cell culture passages from the oocyst stage and are capable of completing both intermediate and definitive host life cycles. These experiments used newly constructed Affymetrix GeneChips that include probe sets for ~8000 genes, and we assessed the induction of bradyzoite genes using a strong inducer of bradyzoite differentiation, Compound 1 (Radke et al., 2006).
2009-05-12 | GSE16037 | GEO
Project description:Two forms of the protozoan parasite Toxoplasma gondii are associated with intermediate hosts such as humans: rapidly growing tachyzoites are responsible for acute illness, whereas slowly dividing encysted bradyzoites can remain latent within the tissues for the life of the host. In order to identify genetic factors associated with parasite differentiation, we have used a strong bradyzoite-specific promoter (identified by promoter trapping) to drive the expression of T. gondii hypoxanthine-xanthine-guanine phosphoribosyltransferase (HXGPRT) in stable transgenic parasites, providing a stage-specific positive/negative selectable marker. Insertional mutagenesis has been carried out on this parental line, followed by bradyzoite induction in vitro and selection in 6-thioxanthine to identify misregulation mutants. Two different mutants fail to induce the HXGPRT gene efficiently during bradyzoite differentiation. These mutants are also defective in other aspects of differentiation: they replicate well under bradyzoite growth conditions, lysing the host cell monolayer as effectively as tachyzoites. Expression of the major bradyzoite antigen BAG1 is reduced, and staining with Dolichos biflorus lectin shows reduced cyst wall formation. Microarray hybridizations show that these mutants behave more like tachyzoites at a global level, even under bradyzoite differentiation conditions. Set of arrays organized by shared biological context, such as organism, tumors types, processes, etc. Keywords: Logical Set
2005-08-13 | GSE3119 | GEO
Project description:Two forms of the protozoan parasite Toxoplasma gondii are associated with intermediate hosts such as humans: rapidly growing tachyzoites are responsible for acute illness, whereas slowly dividing encysted bradyzoites can remain latent within the tissues for the life of the host. In order to identify genetic factors associated with parasite differentiation, we have used a strong bradyzoite-specific promoter (identified by promoter trapping) to drive the expression of T. gondii hypoxanthine-xanthine-guanine phosphoribosyltransferase (HXGPRT) in stable transgenic parasites, providing a stage-specific positive/negative selectable marker. Insertional mutagenesis has been carried out on this parental line, followed by bradyzoite induction in vitro and selection in 6-thioxanthine to identify misregulation mutants. Two different mutants fail to induce the HXGPRT gene efficiently during bradyzoite differentiation. These mutants are also defective in other aspects of differentiation: they replicate well under bradyzoite growth conditions, lysing the host cell monolayer as effectively as tachyzoites. Expression of the major bradyzoite antigen BAG1 is reduced, and staining with Dolichos biflorus lectin shows reduced cyst wall formation. Microarray hybridizations show that these mutants behave more like tachyzoites at a global level, even under bradyzoite differentiation conditions. Set of arrays organized by shared biological context, such as organism, tumors types, processes, etc. User Defined
2005-08-13 | E-GEOD-3119 | biostudies-arrayexpress