Project description:Characterisation of genome-wide chromatin accessibility (tn5-digested, nucleosome depleted) from thymic Treg and thymic Tconv and to obtain the gene regulatory networks defining thymic Tregs in humans.
Project description:Chromatin accessibility was profiled by ATAC-seq in normal and glioblastoma-derived neural stem (GNS) cells, in self-renewing conditions and in response to differentiation stimulus with bone morphogenic protein (BMP).
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:In mammals, extensive chromatin reorganization is essential for reprogramming terminally committed gametes to a totipotent state during preimplantation development. However, the global chromatin landscape and its dynamics in this period remain unexplored. Here we report a genome-wide map of accessible chromatin in mouse preimplantation embryos using an improved assay for transposase-accessible chromatin with high throughput sequencing (ATAC-seq) approach with CRISPR/Cas9-assisted mitochondrial DNA depletion. We show that despite extensive parental asymmetry in DNA methylomes, the chromatin accessibility between the parental genomes is globally comparable after major zygotic genome activation (ZGA). Accessible chromatin in early embryos is widely shaped by transposable elements and overlaps extensively with putative cis-regulatory sequences. Unexpectedly, accessible chromatin is also found near the transcription end sites of active genes. By integrating the maps of cis-regulatory elements and single-cell transcriptomes, we construct the regulatory network of early development, which helps to identify the key modulators for lineage specification. Finally, we find that the activities of cis-regulatory elements and their associated open chromatin diminished before major ZGA. Surprisingly, we observed many loci showing non-canonical, large open chromatin domains over the entire transcribed units in minor ZGA, supporting the presence of an unusually permissive chromatin state. Together, these data reveal a unique spatiotemporal chromatin configuration that accompanies early mammalian development. Mouse preimplantation embryos were obtained from crosses of C57BL/6N and DBA/2N. ATAC-seq was performed in these embryos at various stages in preimplantation development.
Project description:Leukemia initiating cells (LICs) of acute myeloid leukemia (AML) may arise from self-renewing hematopoietic stem cells (HSCs) and from committed progenitors. However, it remains unclear how leukemia-associated oncogenes instruct LIC formation from cells of different origins and if differentiation along the normal hematopoietic hierarchy is involved. Here, using murine models with the driver mutations MLL-AF9 or MOZ-TIF2, we found that regardless of the transformed cell types, myelomonocytic differentiation to the granulocyte macrophage progenitor (GMP) stage is critical for LIC generation. Blocking myeloid differentiation through disrupting the lineage-restricted transcription factor C/EBPa eliminates GMPs, blocks normal granulopoiesis, and prevents AML development. In contrast, restoring myeloid differentiation through inflammatory cytokines “rescues” AML transformation. Our findings identify myeloid differentiation as a critical step in LIC formation and AML development, thus guiding new therapeutic approaches. Examination of chromatin accessibility in Cebpa knock-out and control conditions.
Project description:This is plate-based chromatin accessibility data set from 3 human foetal livers and bone marrow (18-21 PCW). It includes 4,001 cells before QC and 3,611 cells after QC.
Project description:Contrasting chromatin accessibility between activated and quiescent hepatic stellate cells to identify key gene networks for the activation process.
Project description:The aim of the experiment was to identify HAND1 target genes and its impact on chromatin accessibility in relation to cardiac development. A HAND1-null hESC line was used, in which a doxycycline-inducible HAND1-T2A-BFP transgene had been integrated in approximately half of the cells for HAND1 rescue / overexpression. The hESCs were differentiated with BMP4, Activin A and CHIR. On day 2.5, doxycycline was added. On day 3, cells were dissociated and sorted by BFP level using FACS. Samples were immediately processed for RNA-seq and ATAC-seq.
Project description:The experiment aimed to resolve cellular heterogeneity in cardiac differentiation through the purification of different cell populations by lineage markers and analysis of their transcriptomes and chromatin accessibility. The differentiation protocol was designed to promote cell diversity. The addition of SB at day 2, inhibited SMAD2/3 phosphorylation and created a high BMP signalling bias to restrict cardiac differentiation in favour of other mesodermal lineages, whereas the addition of DMH1 at day 2, inhibited SMAD1/5/8 phosphorylation to create a high Activin signaling bias to promote the co-differentiation of endoderm. Cells were sorted based on SOX17-tomato and NKX2-5-GFP knock-in reporters into their major classes: Pop1 = SB_G0_T0 Pop2 = SB_G1_T0 Pop3 = CTRL_G0_T0 Pop4 = CTRL_G1_T0 Pop5 = DM_G0_T0 Pop6 = DM_G1_T0 Pop7 = DM_G1_T1 Pop8 = DM_G0_T1