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GSE34141
Pseudomonas aeruginosa
12 Downloadable Samples
Affymetrix Pseudomonas aeruginosa Array (paeg1a)
Description
Background Small colony variants (SCVs) are slow-growing bacteria, which often show increased resistance to antibiotics and cause latent or recurrent infections. It is therefore important to understand the mechanisms at the basis of this phenotypic switch. Methodology/Principal findings One SCV (termed PAO-SCV) was isolated, showing high resistance to gentamicin and to the cephalosporine cefotaxime. PAO-SCV was prone to reversion as evidenced by emergence of large colonies with a frequency of 10-5 on media without antibiotics while it was stably maintained in presence of gentamicin. PAO-SCV showed a delayed growth, defective motility, and strongly reduced levels of the quorum sensing Pseudomonas quinolone signal (PQS). Whole genome expression analysis further suggested a multi-layered antibiotic resistance mechanism, including simultaneous over-expression of two drug efflux pumps (MexAB-OprM, MexXY-OprM), the LPS modification operon arnBCADTEF, and the PhoP-PhoQ two-component system. Conversely, the genes for the synthesis of PQS were strongly down-regulated in PAOSCV. Finally, genomic analysis revealed the presence of mutations in phoP and phoQ genes as well as in the mexZ gene encoding a repressor of the mexXY and mexABoprM genes. Only one mutation occurred only in REV, at nucleotide 1020 of the tufA gene, a paralog of tufB, both encoding the elongation factor Tu, causing a change of the rarely used aspartic acid codon GAU to the more common GAC, possibly causing an increase of tufA mRNA translation. High expression of phoP and phoQ was confirmed for the SCV variant while the revertant showed expression levels reduced to wild-type levels. Conclusions By combining data coming from phenotypic, gene expression and proteome analysis, we could demonstrate that resistance to aminoglycosides in one SCV mutant is multifactorial including overexpression of efflux mechanisms, LPS modification and is accompanied by a drastic down-regulation of the Pseudomonas quinolone signal quorum sensing system.
Publication Title
Phenotypic and genome-wide analysis of an antibiotic-resistant small colony variant (SCV) of Pseudomonas aeruginosa.
Sample Metadata Fields
No sample metadata fields
View Samples- Arabidopsis thaliana
- 6 Downloadable Samples
- Affymetrix Arabidopsis ATH1 Genome Array (ath1121501)
Description
Alterations of hydrogen peroxide (H2O2) levels have a profound impact on numerous signaling cascades orchestrating stress responses, plant growth and development, including programmed cell death. To expand the repertoire of known molecular mechanisms implicated in H2O2 signaling, we performed a forward chemical screen to identify small molecules that could alleviate the photorespiratory-induced cell death phenotype of Arabidopsis thaliana mutants lacking H2O2 scavenging capacity by peroxisomal CATALASE2. Here, we report the characterization of pakerine, a m-sulfamoyl benzamide from the sulfonamide family. Pakerine alleviates the cell death phenotype of cat2 mutants exposed to photorespiration-promoting conditions and delays dark-induced senescence in wild type Arabidopsis leaves. By using a combination of transcriptomics, metabolomics and affinity purification we identified ABNORMAL INFLORESCENCE MERISTEM 1 (AIM1) as a putative protein target of pakerine. AIM1 is a 3-hydroxyacyl-CoA dehydrogenase involved in β-fatty acid oxidation that contributes to jasmonic acid (JA) and salicylic acid (SA) biosynthesis. Whereas intact JA biosynthesis was not required for pakerine bioactivity, our results point towards a role for β-oxidation-dependent SA production in execution of H2O2-mediated cell death.
Publication Title
Chemical Genetics Approach Identifies Abnormal Inflorescence Meristem 1 as a Putative Target of a Novel Sulfonamide That Protects Catalase2-Deficient <i>Arabidopsis</i> against Photorespiratory Stress.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 4 Downloadable Samples
NextSeq 500
Description
To investigate differential gene expression that might account for the differing glomerular phenotype of NPHS2-Cre +/+ mice when compared with wild-type control, including altered GBM thickness, loss of normal foot process morphology, and decrease in podocyte number, RNA sequencing analysis was performed on glomeruli extracted from both NPHS2-Cre +/+ and wild-type control mice. Overall design: Following isolation of glomeruli using Dynabeads from NPHS2-Cre +/+ and wild-type control mice (n=2 biological replicates per genotype, singly isolated), total RNA was extracted and RNA samples were submited for sample preparation and sequencing.
Publication Title
Podocyte-specific expression of Cre recombinase promotes glomerular basement membrane thickening.
Sample Metadata Fields
Sex, Age, Specimen part, Cell line, Subject
View Samples- Homo sapiens
- 36 Downloadable Samples
- Affymetrix Human Genome U219 Array (hgu219), Affymetrix Human Gene 1.1 ST Array (hugene11st)
Description
Interleukin-6 (IL-6) is an important growth factor for estrogen receptor-alpha (ER) positive breast cancer, and elevated serum IL-6 is associated with poor prognosis. We firstly demonstrated that pSTAT3 is the primary downstream IL-6 signaling pathway in ER-positive breast cancer, using ten different breast cancer cell lines. Three-dimensional cultures of these cell lines were also used to develop a 17-gene IL-6 specific gene signature that could be used to identify IL-6 driven disease. This signature included a variety of genes involved in immune cell function and migration, cell growth and apoptosis, and the tumor microenvironment. To further validate this IL-6 signature, we obtained 36 human ER-positive breast cancer tumor samples with matched serum for gene expression profiling and determination of an IL-6 pathway activation score (PAS). Patients with high IL-6 PAS were also enriched for elevated serum IL-6 (>=10 pg/ml). We then utilized a murine MCF-7 xenograft model to determine the role of IL-6 in ER-positive breast cancer and potential anti-IL-6 therapy in vivo. When IL-6 was administered in vivo, MCF-7 cells engrafted without the need for estrogen supplementation. Subsequently, we prophylactically treated mice at MCF-7 engraftment with an anti-IL-6 antibody (siltuximab), fulvestrant or combination therapy. Siltuximab alone was able to blunt MCF-7 engraftment. Similarly, when tumors were allowed to grow to 125 mm3 before treatment, siltuximab alone demonstrated tumor regressions in 90% (9/10) of tumors. Given the established role for IL-6 in ER+ breast cancer, this data demonstrates the potential for anti-IL-6 therapeutics.
Publication Title
Interleukin-6 is a potential therapeutic target in interleukin-6 dependent, estrogen receptor-α-positive breast cancer.
Sample Metadata Fields
Specimen part
View Samples- Escherichia coli
- 12 Downloadable Samples
- Affymetrix E. coli Genome 2.0 Array (ecoli2)
Description
We measured transcriptional changes resulting from overexpression or downregulation of the GTPase Obg.
Publication Title
Obg and Membrane Depolarization Are Part of a Microbial Bet-Hedging Strategy that Leads to Antibiotic Tolerance.
Sample Metadata Fields
No sample metadata fields
View Samples- Saccharomyces cerevisiae
- 50 Downloadable Samples
- Illumina HiSeq 2500
Description
Transcriptome of S. cerevisiae in shifts between glucose and maltose media with different re-growth conditions Overall design: Cells are pregrown in maltose, then grown for different durations in glucose and then washed back to maltose
Publication Title
A new protocol for single-cell RNA-seq reveals stochastic gene expression during lag phase in budding yeast.
Sample Metadata Fields
Subject
View Samples- Homo sapiens
- 18 Downloadable Samples
- Illumina HiSeq 2000
Description
Organoid technology provides the possibility to culture human colon tissue and patient-derived colorectal cancers (CRC) while maintaining all functional and phenotypic characteristics. Labeling of human colon stem cells (CoSCs), especially in normal and benign tumor organoids, is challenging and therefore limits usability of multi-patient organoid libraries for CoSC research. Here, we developed STAR (STem cell Ascl2 Reporter), a minimal enhancer/promoter element that reports transcriptional activity of ASCL2, a master regulator of LGR5+ CoSC fate. Among others via lentiviral infection, STAR minigene labels stem cells in normal as well as in multiple engineered and patient-derived CRC organoids of different stage and genetic make-up. STAR revealed that stem cell driven differentiation hierarchies and the capacity of cell fate plasticity (de-differentiation) are present at all stages of human CRC development. The flexible and user-friendly nature of STAR applications in combination with organoid technology will facilitate basic research on human adult stem cell biology. Overall design: Cells from different colon organoid types were FACS sorted for stem STemness Ascl2 Reporter activity for transcriptome profiling by RNA-seq.
Publication Title
Specific Labeling of Stem Cell Activity in Human Colorectal Organoids Using an ASCL2-Responsive Minigene.
Sample Metadata Fields
Subject
View Samples- Mus musculus
- 6 Downloadable Samples
- Illumina HiSeq 2500
Description
Somatic ribosomal protein defects have recently been described in cancer, yet their impact on cellular transcription and translation remain poorly understood. Here we integrated mRNA sequencing, ribosome footprinting, polysomal RNA seq and quantitative mass spectrometry datasets obtained from an isogenic mouse lymphoid cell model in order to study the T-cell acute lymphoblastic leukemia (T-ALL) associated R98S mutation in ribosomal protein L10 (RPL10 R98S). RPL10 R98S induced changes in protein levels were to a much larger extent caused by transcriptional then translational changes and RPL10 R98S cells showed a gene signature corresponding to deregulation of hematopoietic transcription factors. Phosphoserine phosphatase (PSPH), a key enzyme in serine biosynthesis, displayed elevated transcription and translation and was one of the proteins showing the strongest upregulation in RPL10 R98S cells. Increased Psph protein levels were confirmed in RPL10 R98S engineered JURKAT cells and in hematopoietic cell cultures derived from Rpl10 R98S knock-in mice. Moreover, elevated serine and glycine biosynthesis in RPL10 R98S cells was supported by metabolic flux analyses. Analysis of PSPH expression levels in T-ALL patient samples revealed that PSPH upregulation is a generalized phenomenon in this disease, associated with elevated circulating serine and glycine levels. Addition of serine and glycine enhanced survival of stromal and myeloid cells, suggesting supportive effects on the hematopoietic niche. Finally, reduction of PSPH expression levels in T-ALL cell lines suppressed their in vitro proliferation and their capacity to expand in T-ALL xenograft models. In conclusion, transcriptome, translatome and proteome analysis of the RPL10 R98S mutation identified RPL10 R98S driven induction of cellular serine biosynthesis. Whereas serine metabolism has been implicated in cancer via PHGDH amplification, this is the first report supporting dependence of ALL cells on the serine biosynthesis enzyme PSPH. Overall design: 3 biological replicates for each condition (RPL10 R98S, RPL10 WT)
Publication Title
Translatome analysis reveals altered serine and glycine metabolism in T-cell acute lymphoblastic leukemia cells.
Sample Metadata Fields
Specimen part, Subject
View Samples- Homo sapiens
- 193 Downloadable Samples
- Affymetrix Human Gene 1.0 ST Array (hugene10st)
Description
Microarrays were used to analyze the gene expression in endoscopic-derived intestinal mucosal biopsies from patients with inflammatory bowel diseas (IBD) and controls
Publication Title
Genetic and Transcriptomic Bases of Intestinal Epithelial Barrier Dysfunction in Inflammatory Bowel Disease.
Sample Metadata Fields
Specimen part, Disease
View Samples- Homo sapiens
- 19 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Hypoxia is a low oxygen condition that occurs in the developing tumor mass and that is associated with poor prognosis and resistance to chemo- and radio-therapy. The definition of the hypoxia gene signature is fundamental for the understanding of tumor biology, as in the case of neuroblastoma, the most common pediatric solid tumor. The issue of identifying a significant group of variables in microarray gene expression experiments is particularly difficult due to the typical high dimensional nature of the data and great effort has been spent in the development of feature selection techniques.
Publication Title
A biology-driven approach identifies the hypoxia gene signature as a predictor of the outcome of neuroblastoma patients.
Sample Metadata Fields
Cell line
View Samples