Ezh2 protein is the enzymatic component of the Polycomb Repressive Complex (PRC)-2, which represses its target genes by methylating lysine 27 of histone H3 (H3K27) and regulates cell proliferation and differentiation during embryonic development. Recently, hot-spot mutations of Ezh2 have been identified in diffused large B cell lymphomas (DLBCLs) and follicular lymphomas (FLs). To investigate if tumor growth is dependent on the enzymatic activity of Ezh2, we have developed a potent and selective small molecule inhibitor, EI1, which inhibits the enzymatic activity of Ezh2 through direct binding and competing with the methyl group donor S-Adenosyl methionine (SAM). EI1-treated cells exhibit genome-wide loss of H3K27 methylation. Furthermore, inhibition of Ezh2 by EI1 in DLBCL cells carrying the Y641 mutations results in decreased proliferation, cell cycle arrest and apoptosis. These results provide strong validation of Ezh2 as a potential therapeutic target for the treatment of cancer with the Ezh2 mutation.
Selective inhibition of Ezh2 by a small molecule inhibitor blocks tumor cells proliferation.
Disease, Cell line
View SamplesThe role of Striatin Interacting Protein 2 (Strip2) in differentiation of embryonic stem cells (ESCs) is still under debate. Strip2 silenced (KD) ESCs were differentiated for 4, 8, 12, and 16 days. We show that Strip2 is distributed in the perinucleus or nuclei of wild type (WT) undifferentiated ESCs, but is localized in high-density nuclear bodies in differentiated cells. CellNet analysis of microarray gene expression data for KD and scrambled control (SCR) embryoid bodies (EBs), as well as immunostainings of key pluripotent factors, demonstrated that KD ESCs remain undifferentiated. This occurs even in 16-day old EBs, which possessed a high tumorigenic potential. Correlated with very high expression levels of epigenetic regulator genes, Hat1 and Dnmt3, enzymatic activities of the histone acetyltransferase type B (HAT1) and DNA (cytosine-5)-methyltransferase 3 beta (DNMT3b) were higher in differentiated 16-day old KD EBs than in SCR or WT EBs. The expression levels of let-7, 290 and 302 microRNA families were opposed in KD ESCs, while KD EBs had levels comparable to WT and SCR ESCs during differentiation. This demonstrates that Strip2 is critical to the onset of differentiation, regulating expression of epigenetic regulators, HAT1 and DNMT3b, as well as microRNAs involved in pluripotency.
STRIP2 Is Indispensable for the Onset of Embryonic Stem Cell Differentiation.
Sex, Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Diet-induced developmental acceleration independent of TOR and insulin in C. elegans.
No sample metadata fields
View SamplesAnalysis of wildtype (N2) C. elegans fed different diets: E. coli OP50, E. coli HT115 and Comamonas DA1877
Diet-induced developmental acceleration independent of TOR and insulin in C. elegans.
No sample metadata fields
View SamplesAnalysis of wildtype (N2) C. elegans fed different diets: E. coli OP50, Comamonas DA1877, and Diluted Comamonas (1:1000 Comamonas DA1877:E. coli OP50)
Diet-induced developmental acceleration independent of TOR and insulin in C. elegans.
No sample metadata fields
View SamplesPolycomb repressive complex 2 (PRC2-EZH2) methylates histone H3 at lysine 27 (H3K27) and is required to maintain gene repression during development. Misregulation of PRC2 is linked to a range of neoplastic malignancies, which is believed to involve methylation of H3K27. However, the full spectrum of non-histone substrates of PRC2 that might also contribute to PRC2 function is not known. We characterized the target recognition specificity of PRC2 and used the resultant data to screen for novel potential targets. The RNA polymerase II (Pol II) transcription factor, Elongin A (EloA), is methylated by PRC2 in vivo. Mutation of the methylated EloA residue decreased repression of many, but not all, PRC2 target genes as measured by both steady state and nascent RNA levels. We propose that PRC2 regulates transcription of a subset of target genes in part via methylation of EloA. Overall design: We examined the transcripitonal profile of EEDnull, EloAnull, EloA mutant, and parental mouse embryonic stem cells by RNAseq. Please note that the .bw processed data file was generated from the *mESC replicate samples together and linked to the corresponding *rep1 sample records.
Polycomb Repressive Complex 2 Methylates Elongin A to Regulate Transcription.
Specimen part, Subject
View SamplesPolycomb repressive complex 2 (PRC2-EZH2) methylates histone H3 at lysine 27 (H3K27) and is required to maintain gene repression during development. Misregulation of PRC2 is linked to a range of neoplastic malignancies, which is believed to involve methylation of H3K27. However, the full spectrum of non-histone substrates of PRC2 that might also contribute to PRC2 function is not known. We characterized the target recognition specificity of PRC2 and used the resultant data to screen for novel potential targets. The RNA polymerase II (Pol II) transcription factor, Elongin A (EloA), is methylated by PRC2 in vivo. Mutation of the methylated EloA residue decreased repression of many, but not all, PRC2 target genes as measured by both steady state and nascent RNA levels. We propose that PRC2 regulates transcription of a subset of target genes in part via methylation of EloA. Overall design: We examined the nascent transcripiton profile of mES cells by adding 5-Bromouridine (BrU) to the media for 10 min. Following RNA isolation, BrU-labelled nascent RNA species were affinity purified using BrdU antibody and sequenced after library preparation. Please note that each .bw file was generated from two replicate samples together and linked to the corresponding *rep1 sample records.
Polycomb Repressive Complex 2 Methylates Elongin A to Regulate Transcription.
Specimen part, Subject
View SamplesAnalysis of wildtype C. elegans (N2) and pcca-1(ok2282) and metr-1(ok521) mutants fed Comamonas DA1877
Integration of metabolic and gene regulatory networks modulates the C. elegans dietary response.
No sample metadata fields
View SamplesThe analysis of several mammalian genomes has revealed between 20,000 to 30,000 genes in each genome, a number that may seem hard to reconcile with the large number of cell types and complex functions of these organisms. The solution to this paradox partly lies in the large array of transcripts that each gene can potentially generate through usage of alternative promoters and the variable levels of transcripts that each gene produces in different tissues and cell types. Thus, in order to understand the mechanisms that control diverse patterns of gene expression in mammals, it is necessary to accurately define the active promoters and monitor their cell or tissue-dependent activity. Previous high throughput strategies for assaying tissue-specific gene expression have primarily relied on measurements of steady-state transcript levels by microarrays or tag sequencing. Here, we employ a new experimental strategy to identify and characterize tissue specific promoters by integrating genome-wide maps of RNA polymerase II (Pol II) binding, chromatin modifications and gene expression profiles. We applied this strategy to mouse embryonic stem cells (mES), and adult brain, heart, kidney, and liver. Our results delineated 24,363 Pol II binding sites throughout the genome, 91% of which correspond to 5 end annotation based on known transcripts and cap-analysis of gene expression (CAGE) and can be regarded as promoters. A majority of these experimentally defined promoters are active in all tissues, while only 4,396 can be characterized as tissue-specific using a quantitative measure of Pol II occupancy. In general, Pol II occupancy at these tissue specific promoters is correlated with the presence of active histone modification marks. However, a set of mES- specific promoters display persistent levels of H3K4me3 in non-ES tissues despite undetectable Pol II binding and transcript. Broadly, our results expand the knowledge of tissue-specific mammalian genes and provide a resource for understanding the transcriptional programs in mammalian development and differentiation.
Genome-wide mapping and analysis of active promoters in mouse embryonic stem cells and adult organs.
No sample metadata fields
View SamplesThe regulatory logic underlying global transcriptional programs controlling development of visceral organs like the pancreas remains undiscovered. Here, we profiled gene expression in 12 purified populations of fetal and adult pancreatic epithelial cells representing crucial progenitor cell subsets, and their endocrine or exocrine progeny. Using probabilistic models to decode the general programs organizing gene expression, we identified co-expressed gene modules in cell subsets that revealed patterns and processes governing progenitor cell development, lineage specification, and endocrine cell maturation. Module network analysis linked established regulators like Neurog3 to unrecognized roles in endocrine secretion and protein transport, and nominated multiple candidate regulators of pancreas development. Phenotyping mutant mice revealed that candidate regulatory genes encoding transcription factors, including Bcl11a, Etv1, Prdm16 and Runx1t1, are essential for pancreas development or glucose control. Our integrated approach provides a unique framework for identifying regulatory networks underlying pancreas development and diseases like diabetes mellitus.
An integrated cell purification and genomics strategy reveals multiple regulators of pancreas development.
Specimen part
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