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GSE71637
Mus musculus
4 Downloadable Samples
Affymetrix Mouse Gene 2.1 ST Array (mogene21st)
Description
The murine thymus produces discrete T cell subsets making either IFN- or IL-17, but the role of the TCR in this developmental process remains controversial. Here we generated a non-transgenic and polyclonal model of reduced TCR expression and signal strength selectively on T cells. Mice haploinsufficient for both CD3 and CD3 (CD3DH) showed normal thymocyte subsets but specific defects in T cell development, namely impaired differentiation of IL-17-producing embryonic V6+ (but not adult V4+) T cells and a marked depletion of IFN--producing CD122+ NK1.1+ (V1-biased) T cells throughout life. As result, adult CD3DH mice showed defective peripheral IFN- responses and were resistant to experimental cerebral malaria. Thus, strong TCR signaling is required within specific developmental windows with distinct V usage and differential cytokine production by effector T cell subsets.
Publication Title
TCR signal strength controls thymic differentiation of discrete proinflammatory γδ T cell subsets.
Sample Metadata Fields
Specimen part
View Samples- Drosophila melanogaster
- 12 Downloadable Samples
- Drosophila Gene 1.1 ST Array (drogene11st)
Description
Coupling immunity and development is essential to ensure survival despite changing internal conditions in the organism. The metamorphosis of the fruit fly represents a striking example of drastic and systemic physiological changes that need to be integrated with the innate immune system. However, the mechanisms that coordinate development and immune cell activity in the transition from larva to adult in Drosophila remain to elucidate. The steroid hormone ecdysone is known to act as a key coordinator of metamorphosis. This hormone activates a nuclear receptor, the Ecdysone Receptor (EcR), which acts as a heterodimer with its partner Ultraspiracle (USP). Together, they activate the transcription of primary response genes, which in turn activate the transcription of a battery of late response genes. We have revealed that regulation of macrophage-like cells (hemocytes) by the steroid hormone ecdysone is essential for an effective innate immune response over metamorphosis. We have shown that in response to ecdysone signalling, hemocytes rapidly up regulate actin dynamics, motility and phagocytosis of apoptotic corpses, and acquire the ability to chemotax to damaged epithelia. Most importantly, individuals lacking ecdysone-activated hemocytes are defective in bacterial phagocytosis and are fatally susceptible to infection by bacteria ingested at larval stages, despite the normal systemic production of antimicrobial peptides. This decrease in survival is comparable to the one observed in pupae lacking immune cells altogether, indicating that ecdysone-regulation is essential to hemocyte immune functions and survival after infection.
Publication Title
Steroid hormone signaling is essential to regulate innate immune cells and fight bacterial infection in Drosophila.
Sample Metadata Fields
Specimen part
View Samples- Escherichia coli str. k-12 substr. mg1655
- 12 Downloadable Samples
- Affymetrix E. coli Genome 2.0 Array (ecoli2)
Description
Bacteria are extremely versatile organisms which rapidly adapt to changing environments. When Escherichia coli cells switch from planktonic growth to biofilm, flagellum formation is turned off, and the production of fimbriae and extracellular polysaccharides is switched on. Here we show that BolA protein is a new bacterial transcription factor which modulates the switch from planktonic to sessile lifestyle. BolA negatively modulates flagella biosynthesis and thus swimming capacity. Furthermore, BolA overexpression favors biofilm formation and involvesinvolving fimbriae-like adhesins and curli production. Our results unraveled for the first time that BolA is a protein with high affinity to DNA, involved in the regulation of several genes of E. coli at a genome-wide scale level. Moreover, this observation further demonstrated that the most significant targets of this protein involved a complex network of genes encoding proteins extremely necessary in biofilm development processes. Herein we propose that BolA is a motile/adhesive transcriptional switch, specifically involved in the transition between the planktonic and the attachment stage of biofilm formation process.
Publication Title
BolA is a transcriptional switch that turns off motility and turns on biofilm development.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 58 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
HER-2 positive breast cancers frequently sustain elevated AKT/mammalian target rapamycin (mTOR) signaling which has been associated with resistance to doxorubicin treatment in the clinic. In our study we investigated if the mTOR inhibitor rapamycin increased the sensitivity to doxorubicin therapy in HB4a, a luminal normal mammary cell line; C5.2, a transformed cell derived from HB4a transfected with HER-2 and SKBR3 that exhibits HER-2 amplification. Flow cytometry analysis showed that the combination treatment for 24 hours with rapamycin 20nM and doxorubicin caused accumulation of HB4a and C5.2 cells in S-G2/M. Otherwise in SKBR3 cells, we observed a relative depletion of cells in S-G2/M and concomitant accumulation in G0/G1 of 10% of the cells. The analysis of IC50 of doxorubicin alone and in combination with rapamycin indicated that the sensitivity was increased 2.37 fold in HB4a, 2.46 in C5.2 and 1.87 in SKBR3, suggesting that rapamycin might have enhanced the effects of doxorubicin. Changes in gene expression resulting from co-treatment demonstrated that functional groups of genes with roles in cell cycle, proliferation, apoptosis regulation were represented in the 3 cells analysed. Other biological functions were exclusively associated with each cell suggesting that the inhibition of mTOR activation induced by HER-2 is complex and depends on the cellular context.
Publication Title
No associated publication
Sample Metadata Fields
Specimen part, Cell line
View Samples- Saccharomyces cerevisiae
- 14 Downloadable Samples
- Affymetrix Yeast Genome 2.0 Array (yeast2)
Description
Arsenic metalloid is a double-edge sword. On the one hand it is a very toxic and powerful carcinogen, and on the other it has been successfully used in the treatment of acute promyelocytic leukemia. In order to prevent the deleterious effects caused by arsenic compounds, almost all living organisms have developed mechanisms to eliminate it. In this study genome-wide response of S. cerevisiae to arsenic shows that this metal interferes with genes involved in the iron homeostasis including those encoding proteins that function in iron uptake, incorporation into FeS clusters, and more. In addition our data indicate that Yap1 transcriptionally controls the iron homeostasis regulator AFT2 as well as its direct target, MRS4. Most importantly in response to arsenate exposure Yap1 strongly regulates the expression of several genes involved in the Fe-S proteins biosynthesis, namely NBP35 and YFH1. Interestingly mRNA levels encoding Fet3, Ferro-O2-oxidoreductase required for high-affinity iron uptake, are drastically destabilized upon arsenic exposure. Such destabilization is due to the 5 to 3 exonuclease Xrn1 localized in the P Bodies. Moreover FET3 mRNA decay is not mediated by Cth2 and is independent on the formation of ROS responsible for the toxic effects of arsenic compounds. Strikingly, in presence of arsenate fet3 mutant shows resistance over the wild-type which leads us to suggest that Fet3 has a role in arsenic toxicity. Unexpectedly arsenic treatment seems to activate the non-reductive iron uptake in order to maintain the cellular iron homeostasis. Furthermore our genetic, biochemical, and physiological analysis demonstrate that aft1 mutant is sensitive to arsenic compounds and such phenotype is reversible upon addition of iron. We also show that arsenic exposure induces iron deficiency in aft1 mutant. In conclusion this work shows for the first time that arsenic, a chemotherapy drug used to treat a specific type of acute promyelocytic leukemia (APL), disrupts iron homeostasis and our results suggest that this disruption is independent on ROS generation. Finally we provide preliminary data confirming that such disruption also takes place in mammalian cells, an observation that can be very relevant in term of clinical applications.
Publication Title
Arsenic stress elicits cytosolic Ca(2+) bursts and Crz1 activation in Saccharomyces cerevisiae.
Sample Metadata Fields
Time
View Samples- Escherichia coli str. k-12 substr. mg1655
- 8 Downloadable Samples
- Affymetrix E. coli Genome 2.0 Array (ecoli2)
Description
We recently reported that carbon monoxide (CO) has bactericidal activity. To understand its mode of action we analysed the gene expression changes occurring when Escherichia coli, grown aerobically and anaerobically, is treated with the carbon monoxide releasing molecule, CORM-2. The E. coli microarray analysis shows that E. coli CORM-2 response is multifaceted with a high number of differentially regulated genes spread through several functional categories, namely genes involved in inorganic ion transport and metabolism, regulators, and genes implicated in posttranslational modification, such as chaperones. CORM-2 has higher impact in E. coli cells grown anaerobically, as judged by the existence of repressed genes belonging to eight functional classes which are absent in aerobically CORM-2 treated cells. In spite of the relatively stable nature of the CO molecule, our results show that CO is able to trigger a significant alteration in the transcriptome of E. coli which necessarily has effects in several key metabolic pathways.
Publication Title
Exploring the antimicrobial action of a carbon monoxide-releasing compound through whole-genome transcription profiling of Escherichia coli.
Sample Metadata Fields
No sample metadata fields
View Samples- Drosophila melanogaster
- 77 Downloadable Samples
- Affymetrix Drosophila Genome Array (drosgenome1)
Description
During the development of the Drosophila central nervous system the process of midline crossing is orchestrated by a number of guidance receptors and ligands. Many key axon guidance molecules have been identified in both invertebrates and vertebrates, but the transcriptional regulation of growth cone guidance remains largely unknown. One open question is whether transcriptional regulation plays a role in midline crossing, or if local translation can account for the necessary fine tuning of protein levels. To investigate this issue, we conducted a genome wide analysis of transcription in Drosophila embryos using wild type and a number of well-characterized Drosophila guidance mutants and transgenics. We also analyzed a publicly available microarray time course of Drosophila embryonic development with an axon guidance focus. Using hopach, a novel clustering method which is well suited to microarray data analysis, we identified groups of genes with similar expression patterns across guidance mutants and transgenics. We then systematically characterized the resulting clusters with respect to their relevance to axon guidance using two complementary controlled vocabularies: the Gene Ontology (GO) and anatomical annotations of the Atlas of Pattern of Gene Expression (APoGE) in situ hybridization database. The analysis indicates that regulation of gene expression does play a role in the process of axon guidance in Drosophila. We also find a strong link between axon guidance and hemocyte migration, a result that agrees with mounting evidence that axon guidance molecules are co-opted in vertebrate vascularization. Cell cyclin activity in the context of axon guidance is also suggested from our array data. RNA and protein patterns of cell cyclin in axon guidance mutants and transgenics support this possible link. This study provides important insights into the regulation of axon guidance in vivo and suggests that transcription does play a role in control of axon guidance.
Publication Title
No associated publication
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 24 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
The prostate stroma is a key mediator of epithelial differentiation and development, and potentially plays a role in the initiation and progression of prostate cancer. Isolation and characterization of viable populations of the constituent cell types of prostate tumors could provide valuable insight into the biology of cancer. The CD90+ stromal fibromuscular cells from tumor specimens were isolated by cell-sorting and analyzed by DNA microarray. Dataset analysis was used to compare gene expression between normal and tumor-associated reactive stromal cells. Reactive stroma is characterized by smooth muscle differentiation, prostate down-regulation of SPOCK3, MSMB, CXCL13, and PAGE4, bladder down-regulation of TRPA1, HSD17B2, IL24, and SALL1, and an up-regulation of CXC-chemokines. This study identified a group of differentially expressed genes in CD90+ reactive stromal cells that are potentially involved in organ development and smooth muscle cell differentiation.
Publication Title
Gene expression down-regulation in CD90+ prostate tumor-associated stromal cells involves potential organ-specific genes.
Sample Metadata Fields
Specimen part
View Samples- Glycine max
- 13 Downloadable Samples
- Affymetrix Soybean Genome Array (soybean)
Description
BiP overexpression confers resistance to drought, through an as yet unknown mechanism that is related to ER functioning, has been described that the delay in leaf senescence by BiP overexpression might relate to the absence of the response to drought.
Publication Title
No associated publication
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 3 Downloadable Samples
- Affymetrix Human Gene 2.0 ST Array (hugene20st)
Description
Plasmacytoid dendritic cells (pDCs) were initially considered as critical for innate immunity to viruses. However, our group has shown that pDCs bind to and inhibit the growth of Aspergillus fumigatus hyphae and that depletion of pDCs renders mice hypersusceptible to experimental aspergillosis. In this study, we examined pDC receptors responsible for hyphal recognition and downstream events in pDCs stimulated by A. fumigatus hyphae. Our data show that Dectin-2 but not Dectin-1 participates in hyphal recognition by pDCs and that Dectin-2 acts in cooperation with the FcR chain to trigger signaling responses. In addition, using confocal and electron microscopy we demonstrated that the interaction between pDCs and A. fumigatus induced the formation of pDC extracellular traps (pETs) containing DNA and citrullinated histone H3. Thus, these structures closely resembled those of neutrophil extracellular traps (NETs). Microarray analysis of the pDC transcriptome upon A. fumigatus infection demonstrated up-regulated expression of genes previously associated with viral infections or apoptosis. Moreover, the abundant expression of type I Interferon-encoding genes seen in CpG-stimulated pDCs was absent in the pDCs infected with A. fumigatus hyphae. Thus, human pDCs directly recognize A. fumigatus hyphae via Dectin-2. This interaction leads to formation of pET and triggers a distinct pattern of pDC gene expression.
Publication Title
No associated publication
Sample Metadata Fields
Specimen part
View Samples