BJAB cells over expressing KSHV PAN RNA
Regulation of viral and cellular gene expression by Kaposi's sarcoma-associated herpesvirus polyadenylated nuclear RNA.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Epipolymorphisms associated with the clinical outcome of autoimmune arthritis affect CD4+ T cell activation pathways.
Sex
View SamplesMultifactorial diseases, including autoimmune juvenile idiopathic arthritis (JIA), result from a complex interplay between genetics and environment. Epigenetic mechanisms are believed to integrate such gene-environment interactions, fine-tuning gene expression and possibly contributing to immune system dysregulation. Although anti-TNF therapy has strongly increased JIA remission rates, it is not curative and up to 80% of patients flare upon treatment withdrawal. Thus, a crucial unmet medical and scientific need is to understand the immunological mechanisms associated with remission or flare to inform clinical decisions. Here, we explored the CD4+ T cell DNA methylome of 68 poly-articular and extended oligo-articular JIA patients, before and after anti-TNF therapy withdrawal, to identify features associated with maintenance of inactive disease (ID). Individual CpG sites were clustered in coherent modules without a priori knowledge of their function through network analysis. The methylation level of several CpG modules, specifically those enriched in CpG sites belonging to genes that mediate T cell activation, uniquely correlated with clinical activity. Differences in DNA methylation were already detectable at the time of therapy discontinuation, suggesting epigenetic predisposition. RNA profiling also detected differences in T cell activation markers, including HLA-DR, but, overall, its sensitivity was lower than epigenetic profiling. Changes to the T cell activation signature at the protein level were detectable by flow cytometry, confirming the biological relevance of the observed alterations in methylation. Our work proposes, for the first time, epigenetic discrimination between clinical activity states, and reveals T cell-related biological functions tied to, and possibly predicting and/or causing, clinical outcome.
Epipolymorphisms associated with the clinical outcome of autoimmune arthritis affect CD4+ T cell activation pathways.
Sex
View SamplesThe basic unit of genome packaging is the nucleosome, and nucleosomes have long been proposed to restrict DNA accessibility both to damage and to transcription. However, nucleosome number in cells was considered fixed, and no condition was described where nucleosome number was reduced. We show here that mammalian cells lacking High Mobility Group Box 1 protein (HMGB1) contain a reduced amount of core, linker and variant histones, and a correspondingly reduced number of nucleosomes. Yeast nhp6 mutants lacking NHP6A and B proteins, which are related to HMGB1, also have a reduced amount of histones and fewer nucleosomes. Nucleosome limitation in both mammalian and yeast cells increases the sensitivity of DNA to damage, increases transcription globally, and the relative expression of about 10% of genes. In yeast nhp6 cells the loss of more than one nucleosome in four does not affect the location of nucleosomes and their spacing, but nucleosomal occupancy. The decrease in nucleosomal occupancy is non-uniform, and our results can be modelled assuming that different nucleosomal sites compete for the available histones: sites with high affinity are almost always packaged into nucleosomes both in wt and nucleosome-depleted cells, whereas sites with low affinity are less frequently packaged in nucleosome-depleted cells. We suggest that by modulating the occupancy of nucleosomes histone availability may constitute a novel layer of epigenetic regulation.
Substantial histone reduction modulates genomewide nucleosomal occupancy and global transcriptional output.
No sample metadata fields
View SamplesTh17 cells were sorted ex vivo from PB of healthy donors as CD4+CD161+CCR6+CXCR3-. Following, cells were transduced with a lentiviral vector carrying the Eomes gene or with an empty vector. Infected cells were then enriched by MACS separation using the reporter gene NGFR as selection marker. Finally, cells were frozen for RNA analysis.
Eomes controls the development of Th17-derived (non-classic) Th1 cells during chronic inflammation.
Cell line
View SamplesGenome-wide studies have identified abundant small, non-coding RNAs including snRNAs, snoRNAs, cryptic unstable transcripts (CUTs), and upstream regulatory RNAs (uRNAs) that are transcribed by RNA polymerase II (pol II) and terminated by a Nrd1-dependent pathway. Here, we show that the prolyl isomerase, Ess1, is required for Nrd1-dependent termination of ncRNAs. Ess1 binds the carboxy terminal domain (CTD) of pol II and is thought to regulate transcription by conformational isomerization of Ser-Pro bonds within the CTD. In ess1 mutants, expression of ~10% of the genome was altered, due primarily to defects in termination of snoRNAs, CUTs, SUTs and uRNAs. Ess1 promoted dephosphorylation of Ser5 (but not Ser2) within the CTD, most likely by the Ssu72 phosphatase, and we provide evidence for a competition between Nrd1 and Pcf11 for CTD-binding that is regulated by Ess1-dependent isomerization. This is the first example of a prolyl isomerase required for interpreting the CTD code.
The Ess1 prolyl isomerase is required for transcription termination of small noncoding RNAs via the Nrd1 pathway.
No sample metadata fields
View SamplesIn this study we applied differential gene expression analysis to exfoliated human urothelia obtained from patients of known bladder disease status. Selected targets from the microarray data were validated in an independent set of samples using a quantitative PCR approach.
A candidate molecular biomarker panel for the detection of bladder cancer.
Specimen part, Disease
View SamplesMutants in the Drosophila gene lethal (3) malignant brain tumor cause malignant growth in the larval brain. This data shows the changes in gene expression profile associated to mutations in l(3)mbt, both in situ in third instar larval brains and in tumors cultured for 1 5 and 10 (T1, T5, T10) rounds of allograft culture
Ectopic expression of germline genes drives malignant brain tumor growth in Drosophila.
No sample metadata fields
View SamplesWe have studied the plasma membrane protein phenotype of human culture-amplified and native Bone Marrow Mesenchymal Stem Cells (BM MSCs). We have found, using microarrays and flow cytometry, that cultured cells express specifically 113 transcripts and 17 proteins that were not detected in hematopoietic cells. These antigens define a lineage-homogenous cell population of mesenchymal cells, clearly distinct from the hematopoietic lineages, and distinguishable from other cultured skeletal mesenchymal cells (periosteal cells and synovial fibroblasts). Among the specific membrane proteins present on cultured MSCs, 9 allowed the isolation from BM mononuclear cells of a minute population of native MSCs. The enrichment in Colony-Forming Units-Fibroblasts was low for CD49b, CD90 and CD105, but high for CD73, CD130, CD146, CD200 and integrin alphaV/beta5. Additionally, the expression of CD73, CD146 and CD200 was down-regulated in differentiated cells. The new marker CD200, because of its specificity and immunomodulatory properties, deserves further in depth studies.
Specific plasma membrane protein phenotype of culture-amplified and native human bone marrow mesenchymal stem cells.
Sex, Age, Specimen part, Treatment
View SamplesMedulloblastoma is the most frequent malignant pediatric brain tumor and is divided into at least four subgroups known as Wnt, SHH, Group 3 and Group 4. Here we characterized gene regulation mechanisms in the most aggressive subtype, Group 3 tumors, through genome-wide chromatin and expression profiling. Our results show that most active distal sites in these tumors are occupied by the transcription factor OTX2. Highly active OTX2 bound enhancers are often arranged as clusters of adjacent peaks and are also bound by the transcription factor NEUROD1. These sites are responsive to OTX2 and NEUROD1 knockdown and could also be generated de novo upon ectopic OTX2 expression in primary cells, showing that OTX2 cooperates with NEUROD1 and plays a major role in maintaining and possibly establishing regulatory elements as a pioneer factor. Among OTX2 target genes we identified the kinase NEK2, whose knockdown and pharmacological inhibition decreased cell viability. Our studies thus show that OTX2 controls the regulatory landscape of Group 3 medulloblastoma through cooperative activity at enhancer elements and contributes to the expression of critical target genes. Overall design: Primary Group 3 Medulloblastomas tumor samples were analyzed by RNA-seq. Group 3 medulloblastoma cell line (D341) was analyzed by RNA-seq. OTX2 was depleted by infection with lentiviral shRNAs (sh OTX2 and sh GFP control). Raw data not provided for primary Medulloblastoma samples due to patient privacy concerns. Submitter states that the raw data for these samples will be submitted to dbGaP.
OTX2 Activity at Distal Regulatory Elements Shapes the Chromatin Landscape of Group 3 Medulloblastoma.
Cell line, Subject
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