RNA sequencing of duodenal polyps in FAP patients treated with plabebo or the drug combination, erlotinib + sulindac Overall design: 69 duodenal RNA sequencing datasets (17 baseline uninvolved from 17 FAP patients, 10 endpoint uninvolved and 16 polyp from 10 FAP patients on placebo, 10 endpont uninvolved and 16 polyp from 10 FAP patients on drug)
Chemoprevention with Cyclooxygenase and Epidermal Growth Factor Receptor Inhibitors in Familial Adenomatous Polyposis Patients: mRNA Signatures of Duodenal Neoplasia.
Specimen part, Treatment, Subject, Time
View SamplesThe ability to generate defined null mutations in mice revolutionized the analysis of gene function in mammals. However, gene-deficient mice generated by using 129-derived embryonic stem (ES) cells may carry large segments of 129 DNA, even when extensively backcrossed to reference strains, such as C57BL/6J, and this may confound interpretation of experiments performed in these mice. Tissue plasminogen activator (tPA), encoded by the PLAT gene, is a fibrinolytic serine protease that is widely expressed in the brain. A large number of neurological abnormalities have been reported in tPA-deficient mice. The studies here compare genes differentially expressed in the brains of Plat-/- mice from two independent Plat-/- mouse derivations to wild-type C57BL/6J mice. One strain denoted “Old” was constructed in ES cells from a 129 mouse and backcrossed extensively to C57BL/6J, and one denoted “New” Plat-/- mouse was constructed using zinc finger nucleases directly in the C57BL/6J-Plat-/- mouse strain. We identify a significant set of genes that are differentially expressed in the brains of Old Plat-/- mice that preferentially cluster in the vicinity of Plat on chromosome 8, apparently linked to more than 20 Mbp of DNA flanking Plat being of 129 origin. No such clustering is seen in the New Plat-/- mice. Overall design: Whole-transcriptome profiling of the cerebral cortex of wild-type control C57BL/6J mice and two independent Plat-/- mice strains on the C57BL/6J background.
Passenger mutations and aberrant gene expression in congenic tissue plasminogen activator-deficient mouse strains.
Age, Specimen part, Cell line, Subject
View SamplesWe are investigating the transcriptional response of yeast to treatment with enediynes or gamma radiation, which generate different extents of double or single strand breaks in DNA.
The DNA-damage signature in Saccharomyces cerevisiae is associated with single-strand breaks in DNA.
No sample metadata fields
View SamplesWe are investigating the transcriptional response of Anc1 deficient yeast under basal and MMS exposed conditions
Anc1, a protein associated with multiple transcription complexes, is involved in postreplication repair pathway in S. cerevisiae.
No sample metadata fields
View SamplesMicroRNAs are 19 to 23 nt RNAs that post-transcriptionally regulate gene expression. Human cells express several hundred miRNAs which regulate important biological pathways such as development, proliferation, and apoptosis. Recently, 12 microRNA genes have been identified within the genome of Kaposis sarcoma-associated herpesvirus; however, their functions are still unknown. To identify host cellular genes that may be targeted by these novel viral regulators, we performed gene expression profiling in cells stably expressing KSHV-encoded miRNAs. Data analysis revealed a set of 81 genes whose expression was significantly changed in the presence of miRNAs. While the majority of changes were below 2-fold, eight genes were down-regulated between 4- and 20-fold. We confirmed miRNA-dependent regulation for three of these genes and found that protein levels of thrombospondin 1 (THBS1) were decreased >10-fold. THBS1 has previously been reported to be down-regulated in KS lesions and has known activity as a strong tumor suppressor and anti-angiogenic factor, exerting its anti-angiogenic effect in part by activating the latent form of TGF-b. We show that reduced THBS1 expression in the presence of viral miRNAs translates into decreased TGF-b activity. These data suggest that KSHV-encoded miRNAs may contribute directly to pathogenesis by down-regulation of THBS1, a major regulator of cell adhesion, migration, and angiogenesis.
Identification of cellular genes targeted by KSHV-encoded microRNAs.
No sample metadata fields
View SamplesChanges in gene regulation have long been known to play important roles in both innate and adaptive immune responses. However, post-transcriptional mechanisms involved in mRNA processing have been poorly studied despite emerging examples of their role as regulators of immune defenses. We sought to investigate the role of mRNA processing in the cellular responses of human macrophages to live bacterial infections. Overall design: Transcriptomic profiles of 198 infected (Listeria and Salmonella) and non-infected samples at multiple time points.
Adaptively introgressed Neandertal haplotype at the OAS locus functionally impacts innate immune responses in humans.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Inflammation-induced repression of chromatin bound by the transcription factor Foxp3 in regulatory T cells.
Specimen part
View SamplesThe transcription factor Foxp3 is indispensable for the ability of regulatory T (Treg) cells to suppress fatal inflammation. Here, we characterized the role of Foxp3 in chromatin remodeling and regulation of gene expression in actively suppressing Treg cells in an inflammatory setting. Although genome-wide Foxp3 occupancy of DNA regulatory elements was similar in resting and in vivo activated Treg cells, Foxp3-bound enhancers were poised for repression only in activated Treg cells. Following activation, Foxp3-bound sites showed reduced chromatin accessibility and selective H3K27 tri-methylation, which was associated with Ezh2 recruitment and downregulation of nearby gene expression. Thus, Foxp3 poises its targets for repression by facilitating formation of repressive chromatin in regulatory T cells upon their activation in response to inflammatory cues.
Inflammation-induced repression of chromatin bound by the transcription factor Foxp3 in regulatory T cells.
Specimen part
View SamplesMicroRNAs are small, non-coding RNAs that post-transcriptionally regulate gene expression by binding to 3UTRs of target mRNAs. Kaposis sarcoma-associated herpesvirus (KSHV), a virus linked to malignancies including primary effusion lymphoma (PEL), encodes 12 miRNA genes, but only a few regulatory targets are known. We found that KSHV-miR-K12-11 shares 100% seed-sequence homology with hsa-miR-155, a miRNA frequently found up-regulated in lymphomas and critically important for B cell development. Based on this seed-sequence homology, we hypothesized that both miRNAs regulate a common set of target genes and as a result, could have similar biological activities.
Kaposi's sarcoma-associated herpesvirus encodes an ortholog of miR-155.
No sample metadata fields
View SamplesWe have investigated whether gene expression signatures can be used to predict inter-individual responses to DNA damaging agents
Genomic predictors of interindividual differences in response to DNA damaging agents.
No sample metadata fields
View Samples