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GSE47406
Staphylococcus aureus
18 Downloadable Samples
Affymetrix S. aureus Genome Array (saureus)
Description
Staphylococcus aureus thymidine-dependent small-colony variants (TD-SCVs) are frequently isolated from patients with chronic S. aureus infections after long-term treatment with trimethoprim-sulfamethoxazole (TMP-SMX). In TD-SCVs, mutations of thymidylate synthase (thyA, TS), essential for DNA synthesis, occur. However, it has never been shown, that TMP-SMX is responsible for the induction and selection of TD-SCVs. Short-term exposure of TMP-SMX induced the TD-SCV phenotype morphologically as shown in transmission electron-microscopy and on the transcriptional level by qRT-PCR in wild-type S. aureus, while selection of TD-SCVs with thyA mutations occurred only rarely after long-term exposure. In reversion experiments with clinical TD-SCVs, all revertants revealed compensating mutations at the initially identified mutation site. Whole DNA microarray analysis of a thyA deletion mutant (thyA), which exhibited the typical TD-SCV phenotype, identified tremendous alterations compared to the wild-type. Important virulence regulators such as agr, arlRS, sarA and major virulence determinants including hla, hlb, sspA, sspB and geh were down-regulated, while genes associated with the colonization capacity like fnbA, fnbB, spa, clfB, sdrC and sdrD were up-regulated. The expression of genes involved in pyrimidine and purine metabolism as well as in nucleotide interconversion changed significantly. The thyA-mutant was attenuated in virulence in both, a Caenorhabditis elegans killing model and an acute murine pneumonia model. Furthermore, competition experiments in vitro and in vivo (using a chronic pneumonia mouse model) revealed a survival and growth advantage of the thyA-mutant under low thymidine conditions and TMP-SMX exposure. In conclusion, our results clearly show for the first time that TMP-SMX induces the TD-SCV phenotype after short-term exposure in S. aureus and that long-term exposure selects thyA mutations providing an advantage for TD-SCVs under specified conditions. Thus, our results help to understand the dynamic processes of induction and selection of S. aureus TD-SCVs during TMP-SMX exposure.
Publication Title
Inactivation of thyA in Staphylococcus aureus attenuates virulence and has a strong impact on metabolism and virulence gene expression.
Sample Metadata Fields
Time
View Samples- Homo sapiens
- 45 Downloadable Samples
- Affymetrix Human Genome U133A 2.0 Array (hgu133a2)
Description
Barrett's esophagus is characterized by the replacement of squamous epithelium with specialized intestinal metaplastic mucosa. The exact mechanisms of initiation and development of Barrett's metaplasia remain unknown, but a hypothesis of successful adaptation against noxious reflux components has been proposed. To search for the repertoire of adaptation mechanisms of Barrett's metaplasia, we employed high-throughput functional genomic and proteomic methods that defined the molecular background of metaplastic mucosa resistance to reflux. Transcriptional profiling was established for 23 pairs of esophageal squamous epithelium and Barrett's metaplasia tissue samples using Affymetrix U133A 2.0 GeneChips and validated by quantitative real-time polymerase chain reaction. Differences in protein composition were assessed by electrophoretic and mass-spectrometry-based methods. Among 2,822 genes differentially expressed between Barrett's metaplasia and squamous epithelium, we observed significantly overexpressed metaplastic mucosa genes that encode cytokines and growth factors, constituents of extracellular matrix, basement membrane and tight junctions, and proteins involved in prostaglandin and phosphoinositol metabolism, nitric oxide production, and bioenergetics. Their expression likely reflects defense and repair responses of metaplastic mucosa, whereas overexpression of genes encoding heat shock proteins and several protein kinases in squamous epithelium may reflect lower resistance of normal esophageal epithelium than Barrett's metaplasia to reflux components. Despite the methodological and interpretative difficulties in data analyses discussed in this paper, our studies confirm that Barrett's metaplasia may be regarded as a specific microevolution allowing for accumulation of mucosal morphological and physiological changes that better protect against reflux injury.
Publication Title
Molecular defense mechanisms of Barrett's metaplasia estimated by an integrative genomics.
Sample Metadata Fields
Sex, Age
View Samples- Mus musculus
- 21 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
RUNX1, a transcription factor mutated in breast cancer, controls the fate of ER-positive mammary luminal cells.
Sample Metadata Fields
Sex, Specimen part
View Samples- Mus musculus
- 15 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
The purpose of this microarray experiment was to obtain reference gene expression patterns of a number of epithelial cell populations [mammary stem cells (MASC), luminal progenitors (LP), alveolar luminal stem/progenitor cells (WC virgin-these are mammary epithelial cells genetically marked by Wap-Cre in virgin females), mature luminal cells (ML, mainly represent ductal luminal cells in virgin females), and alveolar luminal cells (WC preg these are alveolar cells genetically marked by Wap-Cre during mid-gestation)] present in the mammary gland of wildtype adult mice on a C57BL6 genetic background.
Publication Title
RUNX1, a transcription factor mutated in breast cancer, controls the fate of ER-positive mammary luminal cells.
Sample Metadata Fields
Sex, Specimen part
View Samples- Mus musculus
- 6 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
RUNX1 encodes a RUNX family transcription factor (TF) and was recently identified as a novel mutated gene in human luminal breast cancers. We found that Runx1 is expressed in all subpopulations of murine mammary epithelial cells (MECs) except the secretory alveolar luminal cells. Conditional knockout of Runx1 in MECs by MMTV-Cre led to a decrease in luminal MECs, largely due to a profound reduction in the estrogen receptor (ER)-positive mature luminal subpopulation, a phenotype that could be rescued by loss of either Trp53 or Rb1. Mechanistically RUNX1 represses Elf5, a master regulatory TF gene for alveolar cells, and activates Foxa1, a key mature luminal TF gene involved in the ER program. Collectively, our data identified a key regulator of the ER+ luminal lineage whose disruption may contribute to development of ER+ luminal breast cancer when under the background of either TP53 or RB1 loss.
Publication Title
RUNX1, a transcription factor mutated in breast cancer, controls the fate of ER-positive mammary luminal cells.
Sample Metadata Fields
Sex, Specimen part
View Samples- Mus musculus
- 24 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
MicroRNA microarrays and RNA expression arrays were used to identify functional signaling between neural stem cell progenitor cells (NSPC) and brain endothelial cells (EC) that are critical during embryonic development and tissue repair following brain injury.
Publication Title
The role of microRNAs in neural stem cell-supported endothelial morphogenesis.
Sample Metadata Fields
Specimen part, Disease, Treatment
View Samples- Rattus norvegicus
- 38 Downloadable Samples
- Affymetrix Rat Genome 230 2.0 Array (rat2302)
Description
The rat models of colorectal cancer (CRC), such as the azoxymethane (AOM) cancer-inducing model, are important tools for researching cancer initiation pathways. However, there is limited understanding of the expression pathways of underlying normal rat colonic epithelium and how this relates to human colonic epithelium. The aim of this study was to study the acute effects of AOM on the gene and pathway expression of the rat's colonic epithelium, whilst contrasting the background normal global expression patterns along the length of the rat as compared to the normal human colonic epithelium.
Publication Title
Genomic homeostasis is dysregulated in favour of apoptosis in the colonic epithelium of the azoxymethane treated rat.
Sample Metadata Fields
Sex, Specimen part, Treatment
View Samples- Homo sapiens
- 10 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Development of systems allowing the maintenance of native properties of mesenchymal stromal cells (MSC) is a critical challenge for studying physiological functions of skeletal progenitors, as well as towards cellular therapy and regenerative medicine applications. Conventional stem cell culture in monolayer on plastic dishes (2D) is associated with progressive loss of functionality, likely due to the absence of a biomimetic microenvironment and the selection of adherent populations. Here we demonstrate that 2D MSC expansion can be entirely bypassed by culturing freshly isolated bone marrow cells within the pores of 3D scaffolds in a perfusion-based bioreactor system, followed by enzymatic digestion for cell retrieval. The 3D-perfusion system supported MSC growth while maintaining cells of the hematopoietic lineage, and thus generated a cellular environment mimicking some features of the bone marrow stroma. As compared to 2D-expansion, sorted CD45- cells derived from 3D-perfusion culture after the same time (3 weeks) or a similar extent of proliferation (7-8 doublings) maintained a 4.3-fold higher clonogenicity and exhibited a superior differentiation capacity towards all typical mesenchymal lineages, with similar immunomodulatory function in vitro. Transcriptomic analysis performed on MSC from 5 donors validated the robustness of the process and indicated a reduced inter-donor variability as well as a significant upregulation of multipotency-related gene clusters following 3D-perfusion as compared to 2D expansion. The described system offers a model to study how factors of a 3D engineered niche may regulate MSC function and, by streamlining conventional labor-intensive processes, is prone to automation and scalability within closed bioreactor systems.
Publication Title
Expansion of human mesenchymal stromal cells from fresh bone marrow in a 3D scaffold-based system under direct perfusion.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 9 Downloadable Samples
Illumina HiSeq 2500
Description
We used RNA-seq to define the gene expression profiles of intestinal stem cells (ISCs) expanded in Matrigel, degradable poly(ethylene) glycol (PEG) and non-degradable PEG matrices. Comparison of mRNA profiles between ISCs grown in Matrigel and non-degradable PEG show no major differences in expression of gene related to stemness, proliferation and signaling via the Wnt and Notch pathways. These results also show that ISC cultured in degradable PEG matrices upregulate stress- and inflammation-related genes compared with cells expanded in non-degradable PEG matrices. Overall design: mRNA profiles of ISCs cultured in the three types of matrices for 4 days were generated in triplicate
Publication Title
Designer matrices for intestinal stem cell and organoid culture.
Sample Metadata Fields
Subject
View Samples- Mus musculus
- 8 Downloadable Samples
- Affymetrix Mouse Gene 2.1 ST Array (mogene21st)
Description
Lamin A/C was ablated in pancreatic acinar cells using Elastase1 driven, Cre-ErT mediated, LoxP recombination, causing excision of exons 10 and 11 of the Lmna gene
Publication Title
Lamin A/C Maintains Exocrine Pancreas Homeostasis by Regulating Stability of RB and Activity of E2F.
Sample Metadata Fields
Sex
View Samples