This SuperSeries is composed of the SubSeries listed below.
Functionally distinct patterns of nucleosome remodeling at enhancers in glucocorticoid-treated acute lymphoblastic leukemia.
Specimen part, Cell line
View SamplesPrecise nucleosome positioning is an increasingly recognized feature of promoters and enhancers, reflecting complex contributions of DNA sequence, nucleosome positioning, histone modification and transcription factor binding to enhancer activity and regulation of gene expression. Changes in nucleosome position and occupancy, histone variants and modifications, and chromatin remodeling are also critical elements of dynamic transcriptional regulation, but poorly understood at enhancers. We investigated glucocorticoid receptor-associated (GR) nucleosome dynamics at enhancers in acute lymphoblastic leukemia. For the first time, we demonstrate functionally distinct modes of nucleosome remodeling upon chromatin binding by GR, which we term central, non-central, phased, and minimal. Central and non-central remodeling reflect nucleosome eviction by GR and cofactors, respectively. Phased remodeling involves nucleosome repositioning and is associated with rapidly activated enhancers and induction of gene expression. Minimal remodeling sites initially have low levels of enhancerassociated histone modification, but the majority of these regions gain H3K4me2 or H3K27Ac to become de novo enhancers. Minimal remodeling regions are associated with gene ontologies specific to decreased B cell number and mTOR inhibition and may make unique contributions to glucocorticoid-induced leukemia cell death. Our findings form a novel framework for understanding the dynamic interplay between transcription factor binding, nucleosome remodeling, enhancer function, and gene expression in the leukemia response to glucocorticoids.
Functionally distinct patterns of nucleosome remodeling at enhancers in glucocorticoid-treated acute lymphoblastic leukemia.
Specimen part, Cell line
View SamplesNeonates often generate incomplete immunity against intracellular pathogens, although the mechanism of this defect is poorly understood. An important question is whether the impaired development of memory CD8+ T cells in neonates is due to an immature priming environment or lymphocyte-intrinsic defects. Here we show that neonatal and adult CD8+ T cells adopted different fates when responding to equal amounts of stimulation in the same host. While adult CD8+ T cells differentiated into a heterogeneous pool of effector and memory cells, neonatal CD8+ T cells preferentially gave rise to short-lived effector cells and exhibited a distinct gene expression profile. Surprisingly, impaired neonatal memory formation was not due to a lack of responsiveness, but instead because neonatal CD8+ T cells expanded more rapidly than adult cells and quickly became terminally differentiated. Collectively, these findings demonstrate that neonatal CD8+ T cells exhibit an imbalance in effector and memory CD8+ T cell differentiation, which impairs the formation of memory CD8+ T cells in early life Overall design: mRNA profiles of effector CD8+ T cells from neonatal and adult mice
Rapid proliferation and differentiation impairs the development of memory CD8+ T cells in early life.
No sample metadata fields
View SamplesTo define H3K27me3 modified genes in intestinal stem, progenitor and epithelial cells, we performed chromatin immunoprecipitation coupled with high-throughput sequencing (ChIP-Seq). We used RNA-sequencing to profile gene expression changes during intestinal stem cell differentiation into mature villus cells, as well as genes perturbed upon loss of PRC2 activity (deletion of Eed) . We find thousands of genes that change in expression including many H3K27me3 marked genes. The deregulated genes reaveal a intestinal tissue specific role of PRC2. Overall design: H3K27me3, H3K4me2 and RNA Pol2 ChIP-Seq analysis of isolated mouse intestinal stem cells, enterocyte and secretory progenitor cells, and mature villus cells. RNA seq analysis of control mouse villus cells, control intestinal stem cells and Eed-deleted villus.
Acquired Tissue-Specific Promoter Bivalency Is a Basis for PRC2 Necessity in Adult Cells.
No sample metadata fields
View SamplesVariation in gene expression is an important feature of mouse embryonic stem cells (ESCs). However, the mechanisms responsible for global gene expression variation in ESCs are not fully understood. We performed single cell mRNA-seq analysis of mouse ESCs and uncovered significant heterogeneity in ESCs cultured in serum. Using novel computational approaches we define highly variable gene clusters; and reveal their distinct epigenetic characteristics. We show that bivalent genes are prone to expression variation. At the same time, we identify an ESC priming pathway that initiates the exit from the naïve ESC state. Finally, we provide evidence that a large proportion of intracellular network variability is due to the extracellular culture environment. Serum free culture reduces cellular heterogeneity and transcriptome variation in ESCs. Overall design: Single cell mRNA-seq analysis of ES cells cultured with serum
Serum-Based Culture Conditions Provoke Gene Expression Variability in Mouse Embryonic Stem Cells as Revealed by Single-Cell Analysis.
Subject
View SamplesPolycomb Repressive Complex 2 (PRC2) plays crucial roles in transcriptional regulation and stem cell development. However, the context-specific functions associated with alternative subunits remain largely unexplored. Here we show that the related enzymatic subunits EZH1 and EZH2 undergo an expression switch during hematopoiesis. We examine the in vivo stoichiometry of the PRC2 complexes by quantitative proteomics and reveal the existence of an EZH1-SUZ12 sub-complex lacking EED. We provide evidence that EZH1 together with SUZ12 form a non-canonical PRC2 complex, occupy active chromatin domains in the absence of H3K27me3, and positively regulate gene expression. Loss of EZH2 expression leads to global repositioning of EZH1 chromatin occupancy to EZH2 targets. Moreover, we demonstrate that an erythroid-specific enhancer mediates transcriptional activation of EZH1, and a switch from GATA2 to GATA1 controls the developmental EZH1/2 switch by differential association with EZH1 enhancers during erythropoiesis. Thus, the lineage- and developmental stage-specific regulation of PRC2 expression and subunit composition leads to a switch from canonical silencing to non-canonical PRC2 functions during blood stem cell specification. Overall design: Transcriptional profiling in primary human fetal liver proerythroblasts upon lentiviral shRNA-mediated knockdown of EZH1, EZH2, EED, or SUZ12 by RNA-seq analysis.
Developmental control of polycomb subunit composition by GATA factors mediates a switch to non-canonical functions.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Combinatorial assembly of developmental stage-specific enhancers controls gene expression programs during human erythropoiesis.
Specimen part
View SamplesTo facilitate comparative genomic analyses of human fetal and adult cells undergoing erythropoiesis, we employed a serum-free two-phase liquid culture system to expand and differentiate primary human CD34+ hematopoietic stem/progenitor cells (HSPCs) ex vivo. In this experimental context, highly enriched populations of stage-matched, differentiating, primary proerythroblasts (ProEs) were generated. We selected four time points (day 0, CD34+ HSPCs; day 3, 5, and 7, differentiating ProEs) that represented similar stages differentiation for gene expression profiling using microarrays.
Combinatorial assembly of developmental stage-specific enhancers controls gene expression programs during human erythropoiesis.
Specimen part
View SamplesIRF2, IRF6, and MYB are candidate regulators of human erythropoiesis. We here examine primary CD34+ hematopoietic stem/progenitor cells (HSPCs)-derived erythroid progenitors with control, IRF2, IRF6, or MYB shRNA lentiviral transduction prior to differentiation. Gene expression microarray profiling datasets for MYB shRNA and control shRNA were obtained from Gene Expression Omnibus (GEO) under accession number GSE25678. The data were analyzed together with the datasets obtained in this study.
Combinatorial assembly of developmental stage-specific enhancers controls gene expression programs during human erythropoiesis.
Specimen part
View SamplesBreast cancer cell line MDA-MB-231 was treated with DMSO or UF010, a novel HDAC inhibitor for 24 hours. The impact of UF010 treatment on global gene expression was determined.
Identification of histone deacetylase inhibitors with benzoylhydrazide scaffold that selectively inhibit class I histone deacetylases.
Specimen part, Cell line
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