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Staphylococcus aureus
24 Downloadable Samples
Affymetrix S. aureus Genome Array (saureus)
Description
The epidemic character of community-associated methicillin resistant Staphylococcus aureus (CA-MRSA), especially the geographically widespread clone USA300, is poorly understood. USA300 isolates carry a type IV staphylococcal chromosomal cassette mec (SCCmec) element conferring -lactam antibiotic class resistance and a putative pathogenicity island, ACME (arginine catabolic mobile element).
Publication Title
The arginine catabolic mobile element and staphylococcal chromosomal cassette mec linkage: convergence of virulence and resistance in the USA300 clone of methicillin-resistant Staphylococcus aureus.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 12 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
The human and mouse aryl hydrocarbon receptor (hAHR and mAHRb) share limited (58%) transactivation domain sequence identity. Compared to the mAHRb allele, the hAHR displays 10-fold lower relative affinity for prototypical ligands such as 2,3,7,8 tetrachlorodibenzo-p-dioxin (TCDD). However, in previous studies we have demonstrated that the hAHR can display a higher relative ligand binding affinity than the mAHRb for specific AHR ligands such as indirubin. Each receptor has also been shown to differentially recruit LXXLL co-activator-motif proteins and to utilize different TAD subdomains in gene transactivation. Using hepatocytes isolated from C57BL6/J mice (Ahrb/b) and AHRTtr transgenic mice which express hAHR protein specifically in hepatocytes, we investigated whether the hAHR and mAHRb differentially regulate genes. Microarray and quantitative-PCR analysis of Ahrb/b and AHRTtr primary-mouse hepatocytes treated with 10 nM TCDD revealed that a number of established AHR target genes such as Cyp1a1 and Cyp1b1 are significantly induced by both receptors. Remarkably, of the 1752 genes induced by mAHRb and 1186 genes induced by hAHR, only 265 genes (<10%) were significantly activated by both receptors in response to TCDD. Conversely of the 1100 and 779 genes significantly repressed in mAHRb and hAHR hepatocytes respectively, only 462 (<25%) genes were significantly repressed by both receptors in response to TCDD treatment. Genes identified as differentially expressed are known to be involved in a number of biological pathways, including cell proliferation and inflammatory response which suggests that compared to the mAHRb, the hAHR may play contrasting roles in TCDD-induced toxicity and endogenous AHR-mediated gene regulation.
Publication Title
Differential gene regulation by the human and mouse aryl hydrocarbon receptor.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 17 Downloadable Samples
- Affymetrix Human Gene 1.0 ST Array (hugene10st)
Description
Analysis of primary human bronchial epithelial cells grown in air liquid interface, exposed in vitro to whole tobacco cigarette smoke (48 puffs, 48 minutes) and electronic cigarette aerosol (400 puffs, 200 minutes). Electronic cigarette exposures included two flavors (menthol, tobacco) both with, and without nicotine.
Publication Title
Molecular Impact of Electronic Cigarette Aerosol Exposure in Human Bronchial Epithelium.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 4 Downloadable Samples
- Affymetrix Human Gene 1.0 ST Array (hugene10st)
Description
Protein synthesis belongs to the most energy consuming processes in the cell. Lowering oxygen tension below normal (hypoxia) causes a rapid inhibition of global mRNA translation due to the decreased availability of energy. Interestingly, subsets of mRNAs pursue active translation under such circumstances. In human fibrosarcoma cells (HT1080) exposed to prolonged hypoxia (36 h, 1% oxygen) we observed that transcripts are either increasingly or decreasingly associated with ribosomes localized at the endoplasmic reticulum (ER). In a global setting it turned out that only 31% of transcripts showing elevated total-RNA levels were also increasingly present at the ER in hypoxia. These genes, regulated by its expression as well as its ER-localization, belong to the gene ontologys hypoxia response, glycolysis and HIF-1 transcription factor network supporting the view of active mRNA translation at the ER during hypoxia. Interestingly, a large group of RNAs was found to be unchanged at the expression level, but translocate to the ER in hypoxia. Among these are transcripts encoding translation factors and >180 ncRNAs. In summary, we provide evidence that protein synthesis is favoured at the ER and, thus, partitioning of the transcriptome between cytoplasmic and ER associated ribosomes mediates adaptation of gene expression in hypoxia.
Publication Title
Hypoxia-induced gene expression results from selective mRNA partitioning to the endoplasmic reticulum.
Sample Metadata Fields
Specimen part, Cell line
View Samples- Mus musculus
- 12 Downloadable Samples
- Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
Mitogen activated protein kinase (MAPK) signaling regulates differentiation of many cell types. During myogenesis in particular, p38a MAPK (MAPK14) phosphorylates multiple transcriptional regulators to modulate muscle-specific gene expression. Among the p38a MAPK modulated genes is the muscle-specific transcriptional regulator Myogenin (Myog) that is also essential to complete the muscle differentiation program, and while it is known that both p38a MAPK and Myog are critically required for myogenesis, the individual contribution of each of these proteins is poorly defined. Here we show that Myog expression (in the absence of p38a MAPK signaling) is sufficient to establish expression of many late markers of muscle differentiation and to mediate cell migration. However, Myog expression alone did not led to the formation of multinucleated muscle cells, highlighting a critical role for p38a MAPK in myoblast fusion. Using comparative microarray analysis we identified p38a MAPK-dependent genes that are not regulated by Myog
Publication Title
Comparative expression profiling identifies differential roles for Myogenin and p38α MAPK signaling in myogenesis.
Sample Metadata Fields
Cell line
View Samples- Homo sapiens
- 5 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Although practiced clinically for more than 40 years, the use of hematopoietic stem cell (HSC) transplants remains limited by the ability to expand these cells ex vivo. An unbiased screen with primary human HSCs identified a purine derivative, StemRegenin 1 (SR1), that promotes the ex vivo expansion of CD34+ cells. Culture of HSCs with SR1 led to a 50-fold increase in cells expressing CD34 and a 17-fold increase in cells that retain the ability to engraft immunodeficient mice. Mechanistic studies show that SR1 acts by antagonizing the aryl hydrocarbon receptor (AHR). The identification of SR1 and AHR modulation as a means to induce ex vivo HSC expansion should facilitate the clinical use of HSC therapy.
Publication Title
Aryl hydrocarbon receptor antagonists promote the expansion of human hematopoietic stem cells.
Sample Metadata Fields
Specimen part, Time
View Samples- Homo sapiens
- 3 Downloadable Samples
- Affymetrix Human Gene 2.1 ST Array (hugene21st)
Description
We used microarray analysis to investigate if keratinocytes excert an immuno-inflammatory response towards streptococcal M1 protein.
Publication Title
Vigilant keratinocytes trigger pathogen-associated molecular pattern signaling in response to streptococcal M1 protein.
Sample Metadata Fields
Specimen part, Cell line
View Samples- Arabidopsis thaliana
- 8 Downloadable Samples
- Affymetrix Arabidopsis ATH1 Genome Array (ath1121501)
Description
We used the flu mutant of Arabidopsis and a transgenic line that overexpresses the thylakoid-bound ascorbate peroxidase (tAPX) to address the interactions between different reactive oxygen species (ROS) signaling pathways. The conditional flu mutant of Arabidopsis accumulates excess protochlorophyllide in the dark within chloroplast membranes that upon illumination acts as a photosensitizer and generates singlet oxygen (1O2). Immediately after the release of singlet oxygen rapid changes in nuclear gene expression occur. Distinct sets of genes were activated that were different from those induced by other reactive oxygen species, superoxide or hydrogen peroxide (H2O2), suggesting that different types of active oxygen species activate distinct signaling pathways. It was not known whether the pathways operate separately or interact with each other. We have addressed this problem by modulating noninvasively the level of H2O2 in plastids by means of a transgenic line that overexpresses the thylakoid-bound ascorbate peroxidase (tAPX, line 14/2 PMID: 15165186). In the flu mutant overexpressing tAPX, the expression of most of the nuclear genes that were rapidly activated after the release of 1O2 was significantly higher in flu plants overexpressing tAPX, whereas in wild-type plants, overexpression of tAPX had only a very minor impact on nuclear gene expression. The results suggest that H2O2 antagonizes the 1O2-mediated signaling of stress responses as seen in the flu mutant. This cross-talk between H2O2- and 1O2-dependent signaling pathways might contribute to the overall stability and robustness of wild-type plants exposed to adverse environmental stress conditions.
Publication Title
Cross-talk between singlet oxygen- and hydrogen peroxide-dependent signaling of stress responses in Arabidopsis thaliana.
Sample Metadata Fields
No sample metadata fields
View Samples
SRP098696- Mus musculus
- 8 Downloadable Samples
Illumina HiSeq 2000
Description
Type 1 diabetes (T1D) is a chronic autoimmune disease that involves immune mediated destruction of ß cells. How ß cells respond to immune attack is unknown. We identified a population of ß cells during the progression of T1D in non-obese diabetic (NOD) mice that survives immune attack. This population develops from normal ß cells confronted with islet infiltrates. Pathways involving cell movement, growth and proliferation, immune responses, and cell death and survival are activated in these cells. There is reduced expression of ß cell identity genes and diabetes antigens and increased immune inhibitory markers and stemness genes. This new subpopulation is resistant to killing when diabetes is precipitated with cyclosphosphamide. Human ß cells show similar changes when cultured with immune cells. These changes may account for the chronicity of the disease and the long term survival of ß cells in some patients. Overall design: mRNA profiles of top and bottom beta cells were generated by RNA-seq. 4 samples were processed from each population of cells.
Publication Title
β Cells that Resist Immunological Attack Develop during Progression of Autoimmune Diabetes in NOD Mice.
Sample Metadata Fields
Specimen part, Cell line, Subject
View Samples- Mus musculus
- 15 Downloadable Samples
- Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
The aim of this experiment was to investigate the role of KLF3 in regulating gene expression at different stages throughout the erythroid maturation process.
Publication Title
The CACCC-binding protein KLF3/BKLF represses a subset of KLF1/EKLF target genes and is required for proper erythroid maturation in vivo.
Sample Metadata Fields
Specimen part
View Samples