S288C was transformed with plasmids expressing the GCN5 F221A mutant at varying levels. We sought to examine the global impact on gene expression
Linking yeast Gcn5p catalytic function and gene regulation using a quantitative, graded dominant mutant approach.
No sample metadata fields
View SamplesProlactin and progesterone act together to regulate mammary alveolar development, and both hormones have been implicated in breast cancer initiation and progression. Here we show that Elf5, a prolactin-induced ETS transcription factor that specifies the mammary secretory cell lineage, is also induced by progestins in breast cancer cells via a direct mechanism. To define the transcriptional response to progestin elicited via Elf5 we made an inducible Elf5 sh-RNA knock down model in T47D breast cancer cells and used it to prevent the progestin-induction of Elf5. Functional analysis of Affymetrix gene expression data using Gene Ontologies and Gene Set Enrichment Analysis showed enhancement of the progestin effects on cell cycle gene expression. Cell proliferation assays showed a more efficacious progestin-induced growth arrest when Elf5 was kept at baseline levels. These results showed that progestin-induction of Elf5 expression tempered the anti-proliferative effects of progestins in T47D cells, providing a further mechanistic link between prolactin and progestin in the regulation of mammary cell phenotype.
The antiproliferative effects of progestins in T47D breast cancer cells are tempered by progestin induction of the ETS transcription factor Elf5.
Disease, Cell line, Treatment
View SamplesThe aim of this experiment is to determine Hhex targets in the presence and absence of Myc.
Growth-promoting and tumourigenic activity of c-Myc is suppressed by Hhex.
Cell line
View SamplesIn a pilot experiment to reprogramme MEF into endoderm, we infected MEF with the Yamanakas factors (O: Oct4, K: Klf4, S: Sox2, M:Myc), FoxA2 (F) and Gata4 (G). Global gene expression of isolated clones was performed.
Gata4 blocks somatic cell reprogramming by directly repressing Nanog.
No sample metadata fields
View SamplesGraft versus host disease (GVHD) is the most common complication of hematopoietic stem cell transplant (HCT). However, our understanding of the molecular pathways that cause this disease remains incomplete, leading to inadequate treatment strategies. To address this, we measured the gene expression profile of non-human primate (NHP) T cells during acute GVHD. In this study we specifically interrogated the transcriptional signatures of animals treated with FR104 monotherapy and FR104/Sirolimus combination therapy
Combined OX40L and mTOR blockade controls effector T cell activation while preserving T<sub>reg</sub> reconstitution after transplant.
Specimen part, Subject
View SamplesGraft versus host disease (GVHD) is the most common complication of hematopoietic stem cell transplant (HCT). However, our understanding of the molecular pathways that cause this disease remains incomplete, leading to inadequate treatment strategies. To address this, we measured the gene expression profile of non-human primate (NHP) T cells during acute GVHD. In this study we specifically interrogated the transcriptional signatures of animals treated with KY1005 monotherapy and KY1005/Sirolimus combination therapy
Combined OX40L and mTOR blockade controls effector T cell activation while preserving T<sub>reg</sub> reconstitution after transplant.
No sample metadata fields
View SamplesIRE1a is a critical modulator of the unfolded protein response. Its RNAse activity generates the mature transcript for the XBP1 transcription factor and also degrades other ER associated mRNAs in a process termed Regulated IRE1a Dependent mRNA Decay or RIDD. To determine if IRE1a is critical in the response to oncogenic Ras we used ShRNA to knockdown Ire1a or Xbp1 in primary mouse epidermal keratinocytes transduced with a v-HRAS retrovirus.
ER stress and distinct outputs of the IRE1α RNase control proliferation and senescence in response to oncogenic Ras.
No sample metadata fields
View SamplesAlthough glucocorticoids (GCs) are known to exert numerous effects in the hippocampus, their chronic regulatory functions remain poorly understood. Moreover, evidence is inconsistent regarding the longstanding hypothesis that chronic GC exposure promotes brain aging/Alzheimer's disease. Here, we adrenalectomized male F344 rats at 15-months-of-age, maintained them for 3 months with implanted corticosterone (CORT) pellets producing low or intermediate (glucocorticoid-receptor (GR)-activating) blood levels of CORT, and performed microarray/pathway analyses in hippocampal CA1. We defined the chronic GC-dependent transcriptome as 393 genes that exhibited differential expression between Intermediate- and Low-CORT groups. Short-term CORT (4 days) did not recapitulate this transcriptome. Functional processes/pathways overrepresented by chronic CORT-upregulated genes included learning/plasticity, differentiation, glucose metabolism and cholesterol biosynthesis, whereas processes overrepresented by CORT-downregulated genes included inflammatory/immune/glial responses and extracellular structure. These profiles indicate that GCs chronically activate neuronal/metabolic processes while coordinately repressing a glial axis of reactivity/inflammation. We then compared the GC-transcriptome with a previously-defined hippocampal aging transcriptome, revealing a high proportion of common genes. Although CORT and aging moved expression of some common genes in the same-direction, the majority were shifted in opposite directions by CORT and aging (e.g., glial inflammatory genes downregulated by CORT are upregulated with aging). These results contradict the hypothesis that GCs simply promote brain aging, and also suggest that the opposite-direction shifts during aging reflect resistance to CORT regulation. Therefore, we propose a new model in which aging-related GC resistance develops in some target pathways while GC overstimulation develops in others, together generating much of the brain aging phenotype.
Glucocorticoid-dependent hippocampal transcriptome in male rats: pathway-specific alterations with aging.
Sex, Age, Specimen part
View SamplesDifferential gene expression profiles were observed in response to Hras in either wild-type or Ppar-beta null primary keratinocytes and differentail gene edxpression profiles by GW0742 were only found in wild-type keratinocytes.
Peroxisome proliferator-activated receptor β/δ cross talks with E2F and attenuates mitosis in HRAS-expressing cells.
Specimen part
View SamplesThis study characterizes the response of primary human endothelial cells (human umbilical vein endothelial cells, HUVECs) to the relative shear stress changes that occur during the initiation of arteriogenesis at the entrance regions to a collateral artery network. HUVECs were preconditioned to a baseline level of unidirectional shear of 15 dynes/cm2 for 24 hours. After 24 hours preconditioning, HUVECs were subjected to an arteriogenic stimulus that mimics the shear stress changes observed in the opposing entrance regions into a collateral artery network. The arteriogenic stimulus consisted of a 100% step wise increase in shear stress magnitude to a unidirectional 30 dynes/cm2 in either the same or opposite direction of the preconditioned shear stress. This simulates either the feeding entrance to the collateral artery circuit or the region that drains into the vasculature downstream of an obstruction in a major artery, respectively. In vivo analysis of collateral growth in the mouse hindlimb showed enhanced outward remodeling in the re-entrant (direction reversing) region that reconnects to the downstream arterial tree, suggesting reversal of shear stress direction as a key enhancer of arteriogenesis. Transcriptional profiling using microarray techniques identified that the reversal of shear stress direction, but not an increase in shear stress alone, yielded a broad-based enhancement of the mechanotransduction pathways necessary for the induction of arteriogenesis.
Mechanisms of Amplified Arteriogenesis in Collateral Artery Segments Exposed to Reversed Flow Direction.
Specimen part
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