Project description:Genome-wide measurements of histone modifications and transcription factor binding in mouse barelette progenitors, neurons and ESCs at different developmental stages and in different genotypes.
Project description:The experiment was designed to look into chromatin accessibility changes during cell cycle progression in human embryonic stem cells (hESCs) during definitive endoderm differentiation. For this, FUCCI hESCs were sorted in Early G1 (EG1), and differentiation into endoderm was performed for up to 72 hours with a combination of cytokines as described in Pauklin and Vallier (2013) and Pauklin et al. (2016). Samples at 0, 12, 24, 36, 48 and 72 hours were generated from two independent experiments, with 100,000 cells per sample, as previously described in Kumasaka et al. (2016). Library preparation and sequencing were performed at the Wellcome Sanger Institute next-generation sequencing facility. ATAC-seq libraries were prepared with one of i5 and i7 Nextera tags combination (see protocol details), and pooled equimolarly. Sequencing was performed on Illumina HiSeq 2000, 2 x 75bp paired-end reads.
Project description:A single hematopoietic stem cell can give rise to all blood cells with remarkable fidelity. Here, we define the chromatin accessibility and transcriptional landscape controlling this process in thirteen primary cell types that traverse the hematopoietic hierarchy. Exploiting the finding that enhancer landscapes better reflect cell identity than mRNA levels, we enable "enhancer cytometry" for accurate enumeration of pure cell types from complex populations. We further reveal the lineage ontogeny of genetic elements linked to diverse human diseases. In acute myeloid leukemia, chromatin accessibility reveals distinctive regulatory evolution in pre-leukemic HSCs (pHSCs), leukemia stem cells, and leukemic blasts. These leukemic cells demonstrate unique lineage infidelity, confirmed by single cell regulomes. We further show that pHSCs have a competitive advantage that is conferred by reduced chromatin accessibility at HOXA9 targets and is associated with adverse patient outcomes. Thus, regulome dynamics can provide diverse insights into human hematopoietic development and disease. ATAC-seq profiles of hematopoietic and leukemic cell types, across 13 normal hematopoietic cell types and 3 acute myeloid leukemia cell types. The complete data set contains a total of 132 samples.
Project description:Nanog, a core pluripotency factor in the inner cell mass of blastocysts, is also expressed in unipotent primordial germ cells (PGC) in mice1, where its precise role is yet unclear2-4. We investigated this in an in vitro model, where naïve pluripotent embryonic stem cells (ESCs) cultured in bFGF/ActivinA develop as epiblast-like cells (EpiLCs), and gain competence for PGC-like fate5. Consequently, bone morphogenetic protein (BMP4), or ectopic expression of key germline transcription factors Prdm1/ Prdm14/ Tfap2c, directly induce PGC-like cells (PGCLCs) in EpiLCs, but not in ESCs6-8. Here we report an unexpected discovery that Nanog alone can induce PGCLCs in EpiLCs, independently of BMP4. We propose that following the dissolution of the naïve ESC pluripotency network during establishment of EpiLCs9,10, the epigenome is reset for cell fate determination. Indeed, we found genome-wide changes in NANOG binding pattern between ESCs and EpiLCs, indicating epigenetic resetting of regulatory elements. Accordingly, we show that NANOG can bind and activate enhancers of Prdm1 and Prdm14 in EpiLCs in vitro; BLIMP1 (encoded by Prdm1) then directly induces Tfap2c. Furthermore, while SOX2 and NANOG promote the pluripotent state in ESCs, they show contrasting roles in EpiLCs since Sox2 specifically represses PGCLC induction by Nanog. This study demonstrates a broadly applicable mechanistic principle for how cells acquire competence for cell fate determination, resulting in the context-dependent roles of key transcription factors during development. Nanog ChIP-seq
Project description:We show that in vivo MBD2 is mainly recruited to CpG island promoters that are highly methylated. We also report that MBD2 binds to a subset of CpG island promoters that are characterized by the presence of active histone marks and RNA polymerase II (Pol2). At such sites, MBD2 binds downstream of the transcription start site. Active promoters bound by MBD2 show low to medium gene expression levels and H3K36me3 deposition suggesting a putative role for MBD2 in blocking polymerase II (Pol2) elongation at these promoters. To gain further insight into the function of and epigenetic regulation by MBD2 we generated a tagged version of the protein and stably expressed it in the MCF-7 cell line. We mapped genome wide binding of MBD2 by ChIP sequencing (ChIP-seq) and together with base resolution whole genome bisulfite sequencing (WGBS) we were able to determine the methylation content and the role of methylation density at MBD2 enriched regions. We further dissected MBD2 binding properties, taking advantage of a large set of ChIP-seq data including active histone marks, RNA polymerase II (POL2) and strand specific RNA-seq.
Project description:We interrogated the transcriptome using RNA-seq at several stages of an mouse embryonic stem cell to cardiomyocyte directed differentiation protocol. These four stages represent timepoints when differentiating cultures are enriched for embryonic stem cells (ESC), mesodermal cells (MES), cardiac precursors (CP), or cardiomyocytes (CM) respectively. This study revealed many dynamic patterns of mRNAs and long non-coding RNAs (lncRNAs) and identified groups of genes with similar expression patterns during differentiation. RNA-seq analysis of global RNA levels at 4 stages of directed cardiac differentiation of mouse embryonic stem cells. Each stage in biological duplicates
Project description:Chromatin insulators organize the genome into distinct transcriptional domains and contribute to cell type-specific chromatin organization. However, factors regulating tissue-specific insulator function have not yet been discovered. Here we identify the RNA recognition motif-containing protein, Shep, as a direct interactor of two individual components of the gypsy insulator complex in Drosophila. Mutation of shep improves gypsy-dependent enhancer blocking, indicating a role as a negative regulator of insulator activity. Unlike ubiquitously expressed core gypsy insulator proteins, Shep is highly expressed in the central nervous system (CNS) with lower expression in other tissues. We developed a novel, quantitative tissue-specific barrier assay to demonstrate that Shep functions as a negative regulator of insulator activity in the CNS but not in muscle tissue. Additionally, mutation of shep alters insulator complex nuclear localization in the CNS but not other tissues. Consistent with negative regulatory activity, ChIP-seq analysis of Shep in a CNS-derived cell line indicates substantial genome-wide colocalization with a single gypsy insulator component but limited overlap with intact insulator complexes. Taken together, these data reveal a novel, tissue-specific mode of regulation of a chromatin insulator. ChIP-seq of Shep, Su(Hw), and Mod(mdg4)2.2 in Drosophila BG3 cells along with alternate antibodies
Project description:Dosage compensation ensures that males and females, despite unequal number of X chromosomes, equalize for X linked gene expression. In Drosophila, it is achieved by a two-fold up-regulation of most of the genes present on the male X chromosome, and requires the association of the Dosage Compensation Complex (DCC) on the X chromosome. One of the main intriguing aspects of dosage compensation is how this complex is able to target specifically hundreds of sites only on the X chromosome in order to ensure dosage compensation. In order to better understand the targeting of the DCC and the dosage compensation mechanism, we have then decided to analyze the distribution of the DCC as well as the expression levels in male and female in a more complete and precise manner, using microarrays. In this experiment, we present the data used to analyse the distribution of the MSL-1 and MSL-3 protein (part of the DCC complex) on the X chromosome in WT embryos aged from 0H-14H, as well as the distribution of MSL-1 in embryos aged from 4-6H and in male III instar salivary glands. The DNA amplified from the specific immunoprecipitation (MSL-1 or MSL-3 IP) were labelled using Cy5-dCTP and hybridized against DNA amplified from a non specific immunoprecipitation (mock IP), labeled with Cy3 dye. In parralel we present the data used to analyse the expression profile of X-linked genes in WT male or female III instar larvae salivary glands. The cDNA amplified from the RNA extracted from the male or female salivary glands were labelled using Cy5-dUTP and hybridized against the reference sample, labelled with Cy3-dUTP (pool RNA from ON embryos, adultes, and salivary glands mixed at a ratio 1:1:1.and amplified as the RNA from salivary glands). We used for this study a cDNA array developed by the Genecore facility in EMBL, covering the DGC1 and DGC2 cDNA libraries from the Berkeley Drosophila Genome Project, which represents more than 70% of the coding Drosophila genome.
Project description:To experimentally-validate the non-coding status of annotated lncRNAs, we performed ribosome profiling over a developmental timecourse that matched our previously-published (Pauli et al. 2012) developmental transcriptome. We find that many previously-annotated lncRNAs appear to be translated, but in a pattern more akin to 5' leaders of coding genes. Ribosome profiling over 8 stages in early zebrafish development: 2-4 cell, 256 cell, 1K cell, Dome, Shield, Bud, 28hpf and 5dpf