Filters
Technology
Platform
GSE85342
Caenorhabditis elegans
6 Downloadable Samples
Affymetrix C. elegans Genome Array (celegans)
Description
Pseudomonas aeruginosa is an opportunistic pathogen that causes severe health problems. Despite intensive investigation, many aspects of microbial virulence remain poorly understood. We used a high-throughput, high-content, whole-organism, phenotypic screen to identify small molecules that inhibit P. aeruginosa virulence in C. elegans. Approximately half of the hits were known antimicrobials. A large number of hits were non-antimicrobial bioactive compounds, including the cancer chemotherapeutic 5-fluorouracil. We determined that 5-fluorouracil both transiently inhibits bacterial growth and reduces pyoverdine biosynthesis. Pyoverdine is a siderophore that regulates the expression of several virulence determinants and is critical for pathogenesis in mammals. We show that 5-fluorouridine, a downstream metabolite of 5-fluorouracil, is responsible for inhibiting pyoverdine biosynthesis. We also show that 5-fluorouridine, in contrast to 5-fluorouracil, is a genuine anti-virulent compound, with no bacteriostatic or bacteriocidal activity. To our knowledge, this is the first report utilizing a whole-organism screen to identify novel compounds with antivirulent properties effective against P. aeruginosa.
Publication Title
A High-Content, Phenotypic Screen Identifies Fluorouridine as an Inhibitor of Pyoverdine Biosynthesis and Pseudomonas aeruginosa Virulence.
Sample Metadata Fields
Specimen part, Treatment
View Samples- Caenorhabditis elegans
- 9 Downloadable Samples
- Affymetrix C. elegans Genome Array (celegans)
Description
Pseudomonas aeruginosa is a re-emerging opportunistic pathogen with broad antimicrobial resistance. We have previously reported that the major siderophore pyoverdine from this pathogen disrupts mitochondrial networks and induces a lethal hypoxic response in model host Caernorhabditis elegans. However, the mechanism of such cytotoxicity remained unclear. Here, we demonstrate that pyoverdine translocates into host cells, binding to host ferric iron sources. The reduction of host iron content disrupts mitochondrial function such as NADH oxidation and ATP production and activates mitophagy. This activates a specific immune response that is distinct from colonization-based pathogensis and exposure to downstream pyoverdine effector Exotoxin A. Host response to pyoverdine resembles that of a hypoxic crisis or iron chelator treatment. Furthermore, we demonstrate that pyoverdine is a crucial virulence factor in P. aerguinosa pathogenesis against cystic fibrosis patients; F508 mutation in human CFTR increases susceptibility to pyoverdine-mediated damage.
Publication Title
Pyoverdine, a siderophore from Pseudomonas aeruginosa, translocates into C. elegans, removes iron, and activates a distinct host response.
Sample Metadata Fields
Specimen part, Treatment
View Samples- Mus musculus
- 12 Downloadable Samples
Illumina Genome Analyzer II
Description
Here we describe microRNA profiling of a single differentiation pathway from the stem cell through to terminally differentated mature cells. Overall design: Populations corresponding to distinct stages in T lymphocyte development, from the hematopoietic stem cell-enriched Lin-Sca+Kit+ population through to mature CD4+ and CD8+ T cells were FACS-sorted to purity from the bone marrow and thymus of C57BL/6 mice. Total RNA was extract from each population from which microRNA sequencing libraries were constructed.
Publication Title
Dynamic microRNA gene transcription and processing during T cell development.
Sample Metadata Fields
Specimen part, Cell line, Subject
View Samples- Mus musculus
- 4 Downloadable Samples
- Illumina Genome Analyzer II
Description
Here we show the microRNA genes can been very large and displaying many summarizing structural characteristics Overall design: MicroRNA biogenesis was ablated in CD4+ and CD8+ by deleted Rnasen gene (encoding Drosha). Poly A RNAs were extracted and analyzed by ultra high throughput sequencing
Publication Title
Dynamic microRNA gene transcription and processing during T cell development.
Sample Metadata Fields
Specimen part, Cell line, Subject
View Samples- Caenorhabditis elegans
- 21 Downloadable Samples
- Affymetrix C. elegans Genome Array (celegans)
Description
In the arms race of bacterial pathogenesis, bacteria produce an array of toxins and virulence factors that disrupt host processes while hosts respond with immune countermeasures. One key virulence mediator of the ubiquitous, opportunistic, extracellular pathogen Pseudomonas aeruginosa is the iron-binding siderophore pyoverdin (PMID:10722571;PMID: 8550201). The mechanisms used by pyoverdin to acquire iron from the host remain incompletely elucidated. Here we demonstrate that mitochondria represent an important target for iron acquisition and that exposure to this toxin results in loss of mitochondrial membrane potential, altered mitochondrial dynamics, and mitophagy in both Caenorhabditis elegans and mammalian cells. We also show that animal mitophagy protects the consequences of siderophore activity, conferring resistance to pyoverdin-mediated host killing. In C. elegans, the conserved autophagic genes bec-1/BECN1 and lgg-1/LC3, and the mitophagic regulator pink-1/PINK1 are required for iron chelator-elicited mitochondrial turnover and provide protection against iron sequestration by P. aeruginosa, likely by ameliorating the mitochondrial damage. While autophagic mechanisms have been implicated in the destruction of intracellular bacteria via a process called xenophagy (PMID: 24005326), our findings represent the first report of resistance to an extracellular pathogen being conferred by authentic autophagic activity that targets host organelles.
Publication Title
A conserved mitochondrial surveillance pathway is required for defense against Pseudomonas aeruginosa.
Sample Metadata Fields
Specimen part, Treatment
View Samples- Caenorhabditis elegans
- 18 Downloadable Samples
- Affymetrix C. elegans Genome Array (celegans)
Description
LIN-35 is the single C. elegans ortholog of the mammalian pocket protein family members, pRb, p107, and p130. To gain insight into the roles of pocket proteins during development, a microarray analysis was performed with lin-35 mutants. Stage-specific regulation patterns were revealed, indicating that LIN-35 plays diverse roles at distinct developmental stages. LIN-35 was found to repress the expression of many genes involved in cell proliferation in larvae, an activity that is carried out in conjunction with E2F. In addition, LIN-35 was found to regulate neuronal genes during embryogenesis and targets of the intestinal-specific GATA transcription factor, ELT-2, at multiple developmental stages. Additional findings suggest that LIN-35 functions in cell cycle regulation in embryos in a manner that is independent of E2F. A comparison of LIN-35-regulated genes with known fly and mammalian pocket-protein targets revealed a high degree of overlap, indicating strong conservation of pocket protein functions in diverse phyla. Based on microarray results and our refinement of the C. elegans E2F consensus sequence, we were able to generate a comprehensive list of putative E2F-regulated genes in C. elegans. These results implicate a large number of genes previously unconnected to cell cycle control as having potential roles in this process.
Publication Title
Transcriptome profiling of the C. elegans Rb ortholog reveals diverse developmental roles.
Sample Metadata Fields
No sample metadata fields
View Samples- Caenorhabditis elegans
- 6 Downloadable Samples
- Affymetrix C. elegans Genome Array (celegans)
Description
Our slr-2 dataset showed strong overrepresentation of genes previously identified in a serial analysis of gene expression (SAGE) intestinal library (McGhee et al., 2006) (p << 0.01); 812 genes were common to both data sets. Consistent with the deregulation of intestinal genes, we observed repression of several important metabolic pathways, including the TOR and insulin signaling networks, suggesting that slr-2(ku297) mutants experience metabolic stress. We also compared differentially regulated genes in slr-2 and lin-35 single mutants. Again, we saw a statistically significant overlap (p-value < 0.01); 261 genes were present in both data sets. Strikingly, > 75% of genes common both datasets showed expression changes in the same direction, although the common dataset contained an approximately equal mixture of up and downregulated genes. Furthermore, more than fifty genes common to the lin-35 and slr-2 datasets are known to have intestinal-associated functions. That some of these common intestinal genes were absent from the gut SAGE library could be due to differences in the developmental stage of the animals assayed (adults versus L1s) as well as experimental approaches (SAGE versus microarrays)
Publication Title
Coordinated regulation of intestinal functions in C. elegans by LIN-35/Rb and SLR-2.
Sample Metadata Fields
No sample metadata fields
View Samples- Caenorhabditis elegans
- 6 Downloadable Samples
- Affymetrix C. elegans Genome Array (celegans)
Description
The nematode Caenorhabditis elegans offers currently untapped potential for carrying out high-throughput, live-animal screens of low molecular weight compound libraries to identify molecules that target a variety of cellular processes. We previously used a bacterial infection assay in C. elegans to identify 119 compounds that affect host-microbe interactions among 37,214 tested. We subsequently found that one of these small molecules, RPW-24, protects C. elegans from bacterial infection by stimulating the host immune response of the nematode. Using transcriptome profiling, epistasis pathway analyses with C. elegans mutants, and an RNAi screen, we showed that RPW-24 promotes resistance to Pseudomonas aeruginosa infection by inducing the transcription of a remarkably small number of C. elegans genes (~1.3% of all genes) in a manner that partially depends on the evolutionarily-conserved p38 MAP kinase pathway and the transcription factor ATF-7. These data demonstrated that the immunostimulatory activity of RPW-24 is required for its efficacy and define a novel C. elegans-based strategy to identify compounds with activity against antibiotic-resistant bacterial pathogens. Here we present the microarray data that were used to define the genes that are differentially regulated in wild-type nematodes following exposure to RPW-24.
Publication Title
Stimulation of host immune defenses by a small molecule protects C. elegans from bacterial infection.
Sample Metadata Fields
Specimen part, Treatment
View Samples- Mus musculus
- 15 Downloadable Samples
- Affymetrix Mouse Gene 2.0 ST Array (mogene20st)
Description
Uremic media calcification is not only driven by systemic factors such as hyperphosphatemia, but also crticially dependent on vascular smooth muscle cells per se. We hypothesized that the different developmental origins of vscular smooth muscle cells might lead to a heterogeneous susceptibility to develop media calcification.
Publication Title
Heterogeneous susceptibility for uraemic media calcification and concomitant inflammation within the arterial tree.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 5 Downloadable Samples
- Illumina HiSeq 2500
Description
A key limitation in single cell genomics is generating a high-quality single cell suspension that contains rare or difficult to dissociate cell types and is free of RNA degradation or transcriptional stress responses. Samples with unpredictable availability or that must be collected at several timepoints present additional challenges. Using adult mouse kidney, we compared single-cell RNA sequencing (scRNA-seq) data generated using DropSeq with snRNA-seq data generated from nuclei using sNuc-DropSeq, DroNc-seq and 10X Chromium. We validated snRNA-seq on fibrotic kidney from day 14 unilateral ureteral obstruction (UUO). Overall design: Dropseq, sNucDropseq, DroNcSeq and 10X Chromium were used to profile mouse healthy and fibrotic kidneys
Publication Title
Advantages of Single-Nucleus over Single-Cell RNA Sequencing of Adult Kidney: Rare Cell Types and Novel Cell States Revealed in Fibrosis.
Sample Metadata Fields
Subject
View Samples