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SRP032775
Homo sapiens
232 Downloadable Samples
IlluminaHiSeq2000
Description
Immunity to malaria can be acquired through natural exposure to Plasmodium falciparum (Pf), but only after years of repeated infections. Typically, this immunity is acquired by adolescence and confers protection against disease, but not Pf infection per se. Efforts to understand the mechanisms of this immunity are integral to the development of a vaccine that would mimic the induction of adult immunity in children. The current study applies transcriptomic analyses to a cohort from the rural village of Kalifabougou, Mali, where Pf transmission is intense and seasonal. Signatures that correlate with protection from malaria may yield new hypotheses regarding the biological mechanisms through which malaria immunity is induced by natural Pf infection. The resulting datasets will be of considerable value in the urgent worldwide effort to develop a malaria vaccine that could prevent more than a million deaths annually. Overall design: 108 samples; paired pre- and post-challenge for 54 individuals 198 samples; paired pre- and post-challenge for 99 individuals
Publication Title
Transcriptomic evidence for modulation of host inflammatory responses during febrile Plasmodium falciparum malaria.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 878 Downloadable Samples
Affymetrix Human Gene 2.1 ST Array (hugene21st)
Description
Identifying immune correlates of protection and mechanisms of immunity accelerates and streamlines the development of vaccines. RTS,S/AS01E, the most advanced malaria vaccine, has moderate efficacy in African children. In contrast, immunization with sporozoites under antimalarial chemoprophylaxis (CPS immunization) can provide 100% sterile protection in naïve adults. We used systems biology approaches to identify correlates of vaccine-induced immunity based on transcriptomes of peripheral blood mononuclear cells from subjects immunized with RTS,S/AS01E or chemo-attenuated sporozoites stimulated with parasite antigens in vitro. Specifically, we used samples of subjects from two age cohorts and 3 African countries participating in an RTS,S/AS01E pediatric phase 3 trial and malaria-naïve subjects participating in a CPS trial. We identified both pre-immunization and post-immunization transcriptomic signatures correlating with protection. Signatures were validated in independent children and infants from the RTS,S/AS01E phase 3 trial and subjects from an independent CPS trial with high accuracies (>70%). Transcription modules revealed interferon, NF-B, TLR, and monocyte-related signatures associated with protection. Pre-immunization signatures suggest the potential for strategies to prime the immune system before vaccination towards improving vaccine immunogenicity and efficacy. Finally, signatures of protection could be useful to determine efficacy in clinical trials, accelerating vaccine candidate testing. Nevertheless, signatures should be tested more extensively across multiple cohorts and trials to demonstrate their universal predictive capacity.
Publication Title
Antigen-stimulated PBMC transcriptional protective signatures for malaria immunization.
Sample Metadata Fields
Sex, Specimen part, Subject, Time
View Samples- Saccharomyces cerevisiae
- 13 Downloadable Samples
- Affymetrix Yeast Genome 2.0 Array (yeast2)
Description
Resistance of Saccharomyces cerevisiae to high furfural concentration is based on NADPH-dependent reduction by at least two oxireductases.
Publication Title
Resistance of Saccharomyces cerevisiae to high concentrations of furfural is based on NADPH-dependent reduction by at least two oxireductases.
Sample Metadata Fields
No sample metadata fields
View Samples- Pseudomonas aeruginosa
- 6 Downloadable Samples
- Affymetrix Pseudomonas aeruginosa Array (paeg1a)
Description
Biofilms are surface-adhered bacterial communities encased in an extracellular matrix composed of polysaccharides, proteins, and extracelluar (e)DNA, with eDNA being required for the formation and integrity of biofilms. Here we demonstrate that the spatial and temporal release of eDNA is regulated by BfmR, a regulator essential for Pseudomonas aeruginosa biofilm development. The expression of bfmR coincided with localized cell death and DNA release, with high eDNA concentrations localized to the outer part of microcolonies in the form of a ring and as a cap on small clusters. Additionally, eDNA release and cell lysis increased significantly following bfmR inactivation. Genome-wide transcriptional profiling indicated that bfmR was required for repression of genes associated with bacteriophage assembly and bacteriophage-mediated lysis. In order to determine which of these genes were directly regulated by BfmR, we utilized chromatin immunoprecipitation (ChIP) analysis to identify the promoter of PA0691, termed here phdA, encoding a previously undescribed homologue of the prevent-host-death (Phd) family of proteins. Lack of phdA expression coincided with impaired biofilm development, increased cell death and bacteriophage release, a phenotype comparable to bfmR. Expression of phdA in bfmR biofilms restored eDNA release, cell lysis, release of bacteriophages, and biofilm formation to wild type levels. Moreover, overexpression of phdA rendered P. aeruginosa resistant to lysis mediated by superinfective bacteriophage Pf4 which was only detected in biofilms. The expression of bfmR was stimulated by conditions resulting in membrane perturbation and cell lysis. Thus, we propose that BfmR regulates biofilm development by controlling bacteriophage-mediated lysis and thus, cell death and eDNA release, via PhdA.
Publication Title
The novel Pseudomonas aeruginosa two-component regulator BfmR controls bacteriophage-mediated lysis and DNA release during biofilm development through PhdA.
Sample Metadata Fields
No sample metadata fields
View Samples- Pseudomonas aeruginosa
- 6 Downloadable Samples
- Affymetrix Pseudomonas aeruginosa Array (paeg1a)
Description
A hallmark of the biofilm architecture is the presence of microcolonies. However, little is known about the underlying mechanisms governing microcolony formation. In the human pathogen Pseudomonas aeruginosa, microcolony formation is dependent on the two-component regulator MifR, with mifR mutant biofilms exhibiting an overall thin structure lacking microcolonies, and overexpression of mifR resulting in hyper-microcolony formation. Here, we made use of the distinct MifR-dependent phenotypes to elucidate mechanisms associated with microcolony formation. Using global transcriptomic and proteomic approaches, we demonstrate that cells located within microcolonies experience stressful, oxygen limited, and energy starving conditions, as indicated by the activation of stress response mechanisms and anaerobic and fermentative processes, in particular pyruvate fermentation. Inactivation of genes involved in pyruvate utilization including uspK, acnA and ldhA abrogated microcolony formation in a manner similar to mifR inactivation. Moreover, depletion of pyruvate from the growth medium impaired biofilm and microcolony formation, while addition of pyruvate significantly increased microcolony formation. Addition of pyruvate partly restored microcolony formation in mifR biofilms. Moreover, addition of pyruvate to or expression of mifR in lactate dehydrogenase (ldhA) mutant biofilms did not restore microcolony formation. Consistent with the finding of denitrification genes not demonstrating distinct expression patterns in biofilms forming or lacking microcolonies, addition of nitrate did not alter microcolony formation. Our findings indicate the fermentative utilization of pyruvate to be a microcolony-specific adaptation to the oxygen limitation and energy starvation of the P. aeruginosa biofilm environment.
Publication Title
Microcolony formation by the opportunistic pathogen Pseudomonas aeruginosa requires pyruvate and pyruvate fermentation.
Sample Metadata Fields
No sample metadata fields
View Samples- Saccharomyces cerevisiae
- 23 Downloadable Samples
- Affymetrix Yeast Genome 2.0 Array (yeast2)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Unraveling condition-dependent networks of transcription factors that control metabolic pathway activity in yeast.
Sample Metadata Fields
No sample metadata fields
View Samples- Saccharomyces cerevisiae
- 6 Downloadable Samples
- Affymetrix Yeast Genome 2.0 Array (yeast2)
Description
Expression data from wild-type FY4 and GCR2 deletion strain. Impact of the transcription factor Gcr2p on mRNA expression was investigated in the corresponding deletion strain in exponentially growing glucose minimal medium batch cultures.
Publication Title
Unraveling condition-dependent networks of transcription factors that control metabolic pathway activity in yeast.
Sample Metadata Fields
No sample metadata fields
View Samples- Saccharomyces cerevisiae
- 6 Downloadable Samples
- Affymetrix Yeast Genome 2.0 Array (yeast2)
Description
The impact on mRNA expression of the transcription factors Bas1, Pho2, Gcn4 and Gcr2p was investigated in the corresponding deletion strains during exponential growth in glucose minimal media batch cultures.
Publication Title
Unraveling condition-dependent networks of transcription factors that control metabolic pathway activity in yeast.
Sample Metadata Fields
No sample metadata fields
View Samples- Saccharomyces cerevisiae
- 6 Downloadable Samples
- Affymetrix Yeast Genome 2.0 Array (yeast2)
Description
The impact on mRNA expression of the transcription factors Bas1, Pho2, Gcn4 and Gcr2p was investigated in the corresponding deletion strains during exponential growth in glucose minimal media batch cultures.
Publication Title
Unraveling condition-dependent networks of transcription factors that control metabolic pathway activity in yeast.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 6 Downloadable Samples
- Affymetrix Human Genome U133A Array (hgu133a)
Description
We compared gene expression profiles of a human CD4+ T-cell line 24 h after infection with a cell line of the same origin permanently releasing SIVmac251/32H. A new knowledge-based-network approach (Inter-Chain-Finder) was used to identify subnetworks leading to resistance to SIV-induced cell death. Notably, the method can identify not only differentially-expressed key hub genes but also non-differentially expressed, critical, hidden regulators.
Publication Title
Identification of molecular sub-networks associated with cell survival in a chronically SIVmac-infected human CD4+ T cell line.
Sample Metadata Fields
Disease, Disease stage
View Samples