Several bacterial human pathogens regulate the production of virulence factors by temperature, expressing them only at 37 C. Accordingly we show that the production of all P. aeruginosa virulence factors that are dependent on the QS transcriptional regulator RhlR, but only a fraction that are activated by LasR, are induced at 37 C compared to 30 C or 25 C. The RhlR-dependent induction at 37 C is a posttranscriptional effect due to an RNA thermometer of the ROSE family that thermoregulates the expression of rhlAB operon involved in rhamnolipids production, a virulence associated trait. This RNA structure also affects the expression of the downstream rhlR gene. A second thermometer is present upstream lasI and causes a reduced expression of this gene at lower temperatures without causing a significant decrease of the autoinducer 3-oxo-dodecanoyl homoserine lactone.
Regulation of Pseudomonas aeruginosa virulence factors by two novel RNA thermometers.
No sample metadata fields
View SamplesThe role of SPROUTY2 (SPRY2) in human colon cancer is controversial. Our data support a tumorigenic action of SPRY2. We use microarrays to identify SPRY2 target genes in human SW480 ADH colon carcinoma cell line.
SPROUTY-2 represses the epithelial phenotype of colon carcinoma cells via upregulation of ZEB1 mediated by ETS1 and miR-200/miR-150.
Cell line
View SamplesBackground. Although the emergence of RNA sequencing (RNA-seq), microarrays remain in widespread use for gene expression analysis in the clinic. There are over 767,000 RNA microarrays from human samples in public repositories, which are an invaluable resource for biomedical research and personalized medicine. The absolute gene expression analysis allows the transcriptome profiling of all expressed genes under the specific biological condition without the need of a reference sample. However, the background fluorescence represents a challenge to determine the absolute gene expression in microarrays. Given that the Y chromosome is absent in female subjects, we used it as a new approach for absolute gene expression analysis in which the fluorescence of the Y chromosome genes of female subjects was used as the background fluorescence for all the probes in the microarray. This fluorescence was used to establish an absolute gene expression threshold, allowing the differentiation between expressed and non-expressed genes in microarrays.
A novel approach for human whole transcriptome analysis based on absolute gene expression of microarray data.
Sex, Specimen part
View SamplesThe weaning period consist of a critical postnatal window for structural and physiologic maturation of rat beta cells. To investigate transcriptome changes involved in the maturation of beta cells neighboring this period we performed microarray analysis in FACS beta cell enriched populations to detail the global programme of gene expression to identify its changes during this process.
Transcriptome landmarks of the functional maturity of rat beta-cells, from lactation to adulthood.
Sex
View SamplesThis experiment was designed to study if there are differences in gene expression in the adipose tissue of women affected by polycystic ovary syndrome (PCOS) compared to non-hyperandrogenic women. PCOS is the most common endocrinopathy in women of reproductive age, and is characterized by hyperandrogenism and chronic anovulation. This disease is frequently associated with obesity, insulin resistance, and defects in insulin secretion, predisposing these women to type 2 diabetes, atherosclerosis, and cardiovascular disease.
Differential gene expression profile in omental adipose tissue in women with polycystic ovary syndrome.
No sample metadata fields
View SamplesA toxicogenomic analysis from liver of different pharmacological active coumarins (mammea A/BA+A/BB 3:1 and soulatrolide ) was performed on mice treated (20mg/kg/daily) for a whole week to evaluate if such compounds possess or could develop a hazardous profile on liver.
Toxicogenomic analysis of pharmacological active coumarins isolated from Calophyllum brasiliense.
Sex, Specimen part, Treatment
View SamplesThe liver X receptors (LXRs) are ligand-activated nuclear receptors with established roles in the maintenance of lipid homeostasis in multiple tissues. LXRs exert additional biological functions as negative regulators of inflammation, particularly in macrophages. However, the transcriptional responses controlled by LXRs in other myeloid cells, such as dendritic cells (DC), are still poorly understood. Here we used gain- and loss-of-function models to characterize the impact of LXR deficiency on DC activation programs. Our results identified an LXR-dependent pathway that is important for DC chemotaxis. LXR-deficient mature DCs are defective in stimulus-induced migration in vitro and in vivo. Mechanistically, we show that LXRs facilitate DC chemotactic signaling by regulating the expression of CD38, an ectoenzyme important for leukocyte trafficking. Pharmacological or genetic inactivation of CD38 activity abolished LXR-dependent induction of DC chemotaxis. Using the LDLR-/- mouse model of atherosclerosis, we also demonstrated that hematopoietic CD38 expression is important for the accumulation of lipid-laden myeloid cells in lesions, suggesting that CD38 is a key factor in leukocyte migration during atherogenesis. Collectively, our results demonstrate that LXRs are required for efficient emigration of DCs in response to chemotactic signals during inflammation.
LXR nuclear receptors are transcriptional regulators of dendritic cell chemotaxis.
Specimen part
View SamplesTo identify novel LXR target genes, we conducted transcriptional profiling studies using RAW264.7 cells ectopically expressing
Apoptotic cells promote their own clearance and immune tolerance through activation of the nuclear receptor LXR.
Cell line
View SamplesChronic lymphocytic leukemia (CLL) is characterized by the accumulation of malignant CD5+ B lymphocytes (CLL cells) in the peripheral blood, and their progressive infiltration in lymphoid organs.
No associated publication
Specimen part
View SamplesChronic lymphocytic leukemia (CLL) is characterized by the accumulation of malignant CD5+ B lymphocytes (CLL cells) in the peripheral blood, and their progressive infiltration in lymphoid organs. Despite the efforts made, CLL remains an incurable disease. It is therefore crucial to continue searching for new therapeutic agents and targets. Arsenic trioxide (ATO) induces apoptosis in all CLL cases and it could constitute an efficient therapy for this disease.
No associated publication
Specimen part
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