During development, changes in gene transcription are accompanied by changes in chromatin modification but the order and causality of events often remain unclear. Here we address this question using X-chromosome inactivation (XCI), which entails chromosome-wide gene silencing and heterochromatin formation. We initiate XCI in female, mouse embryonic stem cells by inducing Xist expression and monitor subsequent changes in transcription and chromatin modification by allele-specific TTseq and ChIPseq respectively. An unprecedented temporal resolution has enabled us to define early alterations in chromatin that are induced upon Xist RNA coating. Xist-induced repression begins with histone deacetylation, which involves the histone deacetylase HDAC3 and occurs before efficient loss of H3K4me3 and H3K4me1 modifications. Polycomb-associated repressive histone marks accumulate rapidly, starting with PRC1-associated H2AK119Ub and followed by PRC2-associated H3K27me3. However, polycomb accumulates initially at large premarked domains, some of which correspond to Xist entry sites, and then spreads into genes. We also show that spreading can only ensue when transcriptional silencing has occurred. These results establish a detailed epigenomic time course for XCI and reveal a hierarchy of events with chromatin playing an important role in transcriptional silencing of the X chromosome. Overall design: RNAseq on WT and HDAC3 KO cell lines from TX1072 cell line. For WT and HDAC3KO samples RNAseq in 2 replicates (Rep1, Rep2) at 2 different times of DOX induction (0h, 24h).
The Implication of Early Chromatin Changes in X Chromosome Inactivation.
Cell line, Subject
View SamplesSplenic marginal zone lymphoma (SMZL) is a rare, indolent non-Hodgkin’s lymphoma that affects 0.13 per 100,000 persons annually. Overall survival of SMZL is estimated to reach 8 to 11 years in most cases, but up to 30% of SMZL cases develop aggressive presentations resulting in greatly diminished time of survival. SMZL presents with a very heterogeneous molecular profile, making diagnosis problematic and accurate prognosis even less likely. The study herein has utilized this data to assist in identifying a potential diagnostic gene expression signature with highly specific predictive utility for further evaluation among control and SMZL patient samples. Delineation of a unique SMZL signature that could provide diagnostic utility for a malignancy that has historically been difficult to identify. These results should be further investigated and validated in subsequent molecular investigations of SMZL so it may be potentially incorporated into standard oncology practice for improving the understanding and outlook for SMZL patients.
Identification of a Splenic Marginal Zone Lymphoma Signature: Preliminary Findings With Diagnostic Potential.
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View SamplesTo better understand the mechanisms of blockage of myeloid differentiation and apoptosis and induction of proliferation by miR-125b, we proceeded to identify miR-125b target genes involved in these pathways. We analyzed the total cellular gene expression pattern by RNA-sequencing of the parental NB4 myeloid cell line and that transiently transfected with miR-125b. We generated four cDNA libraries corresponding to duplicates of miR-125b and control cells. Overall design: Compare the gene expression levels in miR control transfected cells with that in miR-125b transfected NB4 cells.Â
MicroRNA-125b transforms myeloid cell lines by repressing multiple mRNA.
Specimen part, Cell line, Subject
View SamplesTo better understand the mechanisms of blockage of myeloid differentiation and apoptosis and induction of proliferation by miR-125b, we preceded to identify miR-125b target genes involved in these pathways. We analyzed the total cellular gene expression pattern by RNA-sequencing of the parental 32Dclone3 myeloid cell line and that ectopically expressing miR-125b. We generated four cDNA libraries corresponding to duplicates of miR-125b and control cells. Overall design: Compare the gene expression level in vector transduced 32Dclone3 cells with that in miR-125b transduced 32Dclone3 cells.Â
MicroRNA-125b transforms myeloid cell lines by repressing multiple mRNA.
Specimen part, Cell line, Subject
View SamplesNeural stem cells were sorted according to their activated or quiescent state by flow cytometry using a set of 3 markers (LeX, CD24 and EGFR)
Distinct Molecular Signatures of Quiescent and Activated Adult Neural Stem Cells Reveal Specific Interactions with Their Microenvironment.
Sex, Specimen part
View SamplesLung alveolarization is a complex process that involves interactions between several cell types and leads to considerable increase in gas-exchange surface area. The step designated secondary septation includes elastogenesis from interstitial fibroblasts.
Gene expression profiling in lung fibroblasts reveals new players in alveolarization.
No sample metadata fields
View SamplesWe used microarrays to compared gene expression profilings in various tumors of the kidney.
Balanced Translocations Disrupting SMARCB1 Are Hallmark Recurrent Genetic Alterations in Renal Medullary Carcinomas.
Specimen part
View SamplesMolecular mechanisms that are responsible for the development of human skin epithelial cells are not completely understood so far. As a consequence, the efficiency to establish a pure skin epithelial cell population from human induced pluripotent stem cells (hiPSC) remains poor. Using an approach including RNA interference and high-throughput imaging of early epithelial cells, we could identify candidate kinases which are involved in skin epithelial differentiation. Among them, we found HIPK4 to be an important inhibitor of this process. Indeed, its silencing increased the amount of generated skin epithelial precursors, increased the amount of generated keratinocytes and improved growth and differentiation of organotypic cultures, allowing for the formation of a denser basal layer and stratification with the expression of several keratins. Our data bring substantial input in the regulation of human skin epithelial differentiation and for improving differentiation protocols from pluripotent stem cells.
An RNAi Screen Reveals an Essential Role for HIPK4 in Human Skin Epithelial Differentiation from iPSCs.
Specimen part, Time
View SamplesWe used RNA sequencing to characterize gene expression of CD4+ CD8a+ double positive (DP), Foxp3+ Treg (TR) and CD4+ single positive (SP) cells in the lamina propria (LP) and intraepithelial compartment (IEL) that had differentiante from the same clonal transnuclear (TN) precursor. Overall design: We adoptively transferred CD4+ CD8a- Foxp3-GFP- isolated from pTregTN/RKO/Foxp3-GFP mice into TCRaßKO hosts. After 6 weeks, we sorted transferred CD4+ CD8a+, Foxp3+ pTreg as well as unconverted CD4+ CD8a- Foxp3-GFP- from the small intestine LP and IEL compartments for whole transcriptome analysis by mRNA sequencing.
Tissue-specific emergence of regulatory and intraepithelial T cells from a clonal T cell precursor.
Specimen part, Subject
View SamplesWe are investigating hepatic transcriptional responses associated with castration and tumorigenic hepatitis induced by Helicobacter hepaticus infection in mature male A/JCr mice
Hepatocellular carcinoma associated with liver-gender disruption in male mice.
No sample metadata fields
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