ES cells differentiated in the presence of the Wnt inhibitor DKK1 fail to express the transcription factor Snail and undergo EMT. We generated an ES cell line, A2.snail, that induced Snail expression upon addition of doxycycline addition.
Snail and the microRNA-200 family act in opposition to regulate epithelial-to-mesenchymal transition and germ layer fate restriction in differentiating ESCs.
Specimen part, Cell line, Time
View SamplesIn order to elucidate the molecular mechanisms underlying individual variation in sensitivity to ethanol we profiled the prefrontal cortex transcriptomes of two inbred strains that exhibit divergent responses to acute ethanol, the C57BL6/J (B6) and DBA/2J (D2) strains, as well as 27 members of the BXD recombinant inbred panel, which was derived from a B6 x D2 cross. With this dataset we were able to identify several gene co-expression networks that were robustly altered by acute ethanol across the BXD panel. These ethanol-responsive gene-enriched networks were heavily populated by genes regulating synaptic transmission and neuroplasticity, and showed strong genetic linkage to discreet chromosomal loci. Network-based measurements of node importance identified several hub genes as established regulators of ethanol response phenotypes, while other hubs represent novel candidate modulators of ethanol responses.
Genetic dissection of acute ethanol responsive gene networks in prefrontal cortex: functional and mechanistic implications.
Sex, Specimen part
View SamplesLigand-mediated activation of the nuclear hormone receptor PPAR gamma lowers blood pressure and improves glucose tolerance in humans. Two naturally occurring mutations (P467L, V290M) in the ligand binding domain of PPAR gamma have been described in humans that lead to severe insulin resistance and hypertension. Experimental evidence suggests that these mutant versions of PPAR gamma act in a dominant negative fashion. To better understand the molecular mechanisms underlying PPAR gamma action in the vasculature, we determined the gene expression patterns in mouse aorta in response to activation or interference with the PPAR gamma signaling pathway.
Bioinformatic analysis of gene sets regulated by ligand-activated and dominant-negative peroxisome proliferator-activated receptor gamma in mouse aorta.
No sample metadata fields
View SamplesParticulate Matter Triggers Carotid Body Dysfunction, Respiratory Dysynchrony and Cardiac Arrhythmias in Mice with Cardiac Failure
Particulate matter induces cardiac arrhythmias via dysregulation of carotid body sensitivity and cardiac sodium channels.
Age, Specimen part
View SamplesFluorescent-labeled zebrafish RAS-induced embryonal rhabdomyosarcoma (ERMS) were created to facilitate in vivo imaging of tumor-propagating cells, regional tumor heterogeneity, and dynamic cell movements in diverse cellular compartments. Using this strategy, we have identified a molecularly distinct ERMS cell subpopulation that expresses high levels of myf5 and is enriched for ERMS-propagating potential when compared with other tumor-derived cells. Embryonal rhabdomyosarcoma (ERMS) is an aggressive pediatric sarcoma of muscle. Here, we show that tumor-propagating potential is confined to myf5+ERMS cells and can be visualized in live, fluorescent transgenic zebrafish. During early tumor growth, myf5+ERMS cells reside within an expanded satellite cell compartment, but by late stage ERMS, myf5+cells are dynamically reorganized into distinct regions separated from differentiated tumor cells. Human ERMS also contain distinct areas of differentiated and undifferentiated cells. Time-lapse imaging revealed that myf5+ERMS cells populate newly formed tumor only after seeding by highly migratory myogenin+ ERMS cells. This finding helps explain the clinical observation that Myogenin positivity correlates with poor clinical outcome in human ERMS and suggests that differentiated tumor cells play critical roles in metastasis. One-cell stage myf5-GFP/mylz2-mCherry fluorescent transgenic zebrafish were injected with rag2-kRAS12D. A subset of animals developed ERMS. Tumor cells were transplanted into syngeneic recipient animals that lacked fluorescent reporter expression. ERMS cell subfractions were isolated from transplant animals and purified cell populations obtained following two rounds of FACS. Sorted cells were 1) analyzed by microarray/RT-PCR and 2) transplanted at limiting dilution into syngeneic animals. These experiments confirm that zebrafish ERMS contain molecularly distinct cell subfractions that express high levels of myf5-GFP and exhibit difference in gene expression when compared to other ERMS cell subtypes. All four fluorescent-labeled cell populations were analyzed (n=2 tumors total).
In vivo imaging of tumor-propagating cells, regional tumor heterogeneity, and dynamic cell movements in embryonal rhabdomyosarcoma.
Specimen part, Disease, Disease stage, Subject
View SamplesThe goal of this study was to identify genes that are differentially expressed after genetic deletion of both alleles of the Cyp26a1 gene in murine embryonic stem cells. Cyp26a1 codes for the CYP26A1 enzyme which metabolizes RA to polar RA metabolites, such as 4-oxo-RA and 4-OH-RA. CYP26A1-/- ES cells do not metabolize RA within 48 hours of RA treatment while in Wt ES cells, polar RA metabolites are already detectable by 8 hr. In addition, the absence of CYP26A1 enzyme increases intracellular RA levels. By gene microarray analysis, we wanted to identify genes that would be affected by the lack of the Cyp26a1 gene.
CYP26A1 knockout embryonic stem cells exhibit reduced differentiation and growth arrest in response to retinoic acid.
No sample metadata fields
View SamplesThe human cytomegalovirus (HCMV) encodes the chemokine receptor US28 that exhibits constitutive activity. NIH-3T3 cells stably transfected with US28 present a pro-angiogenic and transformed phenotype both in vitro and in vivo.
The human cytomegalovirus-encoded chemokine receptor US28 promotes angiogenesis and tumor formation via cyclooxygenase-2.
No sample metadata fields
View SamplesAmong the multiple mechanisms that control the intensity and duration of macrophage activation, the development of a state of refractoriness to a second stimulation in cells treated with LPS has long been recognized. Release of inhibitory cytokines and alterations in intracellular signaling pathways may be involved in the development of LPS tolerance. Although a number of molecules have been implicated, a detailed picture of the molecular changes in LPS tolerance is still missing. We have used a genome-wide gene expression analysis approach to (i) define which fraction of LPS target genes are subject to tolerance induction and (ii) identify genes that are expressed at high levels in tolerant macrophages. Our data show that in LPS tolerant macrophages the vast majority of LPS-induced gene expression is abrogated. The extent of tolerance induction varies for individual genes, and a small subset appears to be excepted. Compared to other negative control mechanisms of macrophages, e.g. IL-10-induced deactivation, LPS-tolerance inhibits a much wider range of transcriptional targets. Some previously described negative regulators of TLR-signaling (e.g. IRAK-M) were confirmed as expressed at higher levels in LPS-tolerant macrophages. In addition, we discuss other potential players in LPS tolerance identified in this group of genes.
A genome-wide analysis of LPS tolerance in macrophages.
No sample metadata fields
View SamplesPU.1 is a key transcription factor for macrophage differentiation. Novel PU.1 target genes were identified by mRNA profiling of PU.1-deficient progenitor cells (PUER) before and after PU.1 activation. We used two different types of Affymetrix DNA-microarrays (430 2.0 arrays and ST 1.0 exon arrays) to characterize the global PU.1-regulated transcriptional program underlying the early processes of macrophage differentiation.
Transcriptomic profiling identifies a PU.1 regulatory network in macrophages.
No sample metadata fields
View SamplesThe role of the renin-angiotensin system in chronic kidney disease involves multiple peptides and receptors. Exerting antipodal pathophysiological mechanisms, renin inhibition and AT1 antagonism ameliorate renal damage.
AT1 antagonism and renin inhibition in mice: pivotal role of targeting angiotensin II in chronic kidney disease.
Age, Specimen part, Treatment
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