Project description:We have analyzed publicly available K562 Hi-C data, which enables genome-wide unbiased capturing of chromatin interactions, using a Mixture Poisson Regression Model to define a highly specific set of interacting genomic regions. We integrated multiple ENCODE Consortium resources with the Hi-C data, using DNase-seq data and ChIP-seq data for 46 transcription factors and 8 histone modifications. We classified 12 different sets (clusters) of interacting loci that can be distinguished by their chromatin modifications and which can be categorized into three types of chromatin hubs. The different clusters of loci display very different relationships with transcription factor binding sites. As expected, many of the transcription factors show binding patterns specific to clusters composed of interacting loci that encompass promoters or enhancers. However, cluster 6, which is distinguished by marks of open chromatin but not by marks of active enhancers or promoters, was not bound by most transcription factors but was highly enriched for 3 transcription factors (GATA1, GATA2, and c-Jun) and 3 chromatin modifiers (BRG1, INI1, and SIRT6). To validate the identification of the clusters and to dissect the impact of chromatin organization on gene regulation, we performed RNA-seq analyses before and after knockdown of GATA1 or GATA2. We found that knockdown of the GATA factors greatly alters the expression of genes within cluster 6. Our work, in combination with previous studies linking regulation by GATA factors with c-Jun and BRG1, provide genome-wide evidence that Hi-C data identifies sets of biologically relevant interacting loci. RNA-seq of control, siGATA1 and siGATA2 K562 cells
Project description:While comparative genetic analysis has been performed between distinct regions of the embryonic forebrain, a comprehensive characterization of differential epigenomic organization has not been performed. We collected single-cell chromatin accessibility profiles from four distinct neurogenic regions of the embryonic mouse forebrain using single nuclei ATAC-Seq (snATAC-Seq). We identified thousands of differentially accessible peaks, many restricted to distinct progenitor cell types or brain regions. We integrated snATAC-Seq and single cell transcriptome data to characterize changes of chromatin accessibility at enhancers and promoters that were tightly coupled to transcript abundance. Multi-modal integration of histone modifications (CUT&Tag and CUT&RUN), promoter-enhancer interactions (Capture-C) and high-order chromatin structure (Hi-C) extended these initial observations. This dataset reveals a diverse chromatin landscape with region-specific regulatory mechanisms and genomic interactions in distinct neurogenic regions of the embryonic mouse brain and represents an extensive public resource of a ‘ground truth’ epigenomic landscape at this critical stage of neurogenesis.
Project description:While comparative genetic analysis has been performed between distinct regions of the embryonic forebrain, a comprehensive characterization of differential epigenomic organization has not been performed. We collected single-cell chromatin accessibility profiles from four distinct neurogenic regions of the embryonic mouse forebrain using single nuclei ATAC-Seq (snATAC-Seq). We identified thousands of differentially accessible peaks, many restricted to distinct progenitor cell types or brain regions. We integrated snATAC-Seq and single cell transcriptome data to characterize changes of chromatin accessibility at enhancers and promoters that were tightly coupled to transcript abundance. Multi-modal integration of histone modifications (CUT&Tag and CUT&RUN), promoter-enhancer interactions (Capture-C) and high-order chromatin structure (Hi-C) extended these initial observations. This dataset reveals a diverse chromatin landscape with region-specific regulatory mechanisms and genomic interactions in distinct neurogenic regions of the embryonic mouse brain and represents an extensive public resource of a ‘ground truth’ epigenomic landscape at this critical stage of neurogenesis.
Project description:While comparative genetic analysis has been performed between distinct regions of the embryonic forebrain, a comprehensive characterization of differential epigenomic organization has not been performed. We collected single-cell chromatin accessibility profiles from four distinct neurogenic regions of the embryonic mouse forebrain using single nuclei ATAC-Seq (snATAC-Seq). We identified thousands of differentially accessible peaks, many restricted to distinct progenitor cell types or brain regions. We integrated snATAC-Seq and single cell transcriptome data to characterize changes of chromatin accessibility at enhancers and promoters that were tightly coupled to transcript abundance. Multi-modal integration of histone modifications (CUT&Tag and CUT&RUN), promoter-enhancer interactions (Capture-C) and high-order chromatin structure (Hi-C) extended these initial observations. This dataset reveals a diverse chromatin landscape with region-specific regulatory mechanisms and genomic interactions in distinct neurogenic regions of the embryonic mouse brain and represents an extensive public resource of a ‘ground truth’ epigenomic landscape at this critical stage of neurogenesis.
Project description:While comparative genetic analysis has been performed between distinct regions of the embryonic forebrain, a comprehensive characterization of differential epigenomic organization has not been performed. We collected single-cell chromatin accessibility profiles from four distinct neurogenic regions of the embryonic mouse forebrain using single nuclei ATAC-Seq (snATAC-Seq). We identified thousands of differentially accessible peaks, many restricted to distinct progenitor cell types or brain regions. We integrated snATAC-Seq and single cell transcriptome data to characterize changes of chromatin accessibility at enhancers and promoters that were tightly coupled to transcript abundance. Multi-modal integration of histone modifications (CUT&Tag and CUT&RUN), promoter-enhancer interactions (Capture-C) and high-order chromatin structure (Hi-C) extended these initial observations. This dataset reveals a diverse chromatin landscape with region-specific regulatory mechanisms and genomic interactions in distinct neurogenic regions of the embryonic mouse brain and represents an extensive public resource of a ‘ground truth’ epigenomic landscape at this critical stage of neurogenesis.
Project description:While comparative genetic analysis has been performed between distinct regions of the embryonic forebrain, a comprehensive characterization of differential epigenomic organization has not been performed. We collected single-cell chromatin accessibility profiles from four distinct neurogenic regions of the embryonic mouse forebrain using single nuclei ATAC-Seq (snATAC-Seq). We identified thousands of differentially accessible peaks, many restricted to distinct progenitor cell types or brain regions. We integrated snATAC-Seq and single cell transcriptome data to characterize changes of chromatin accessibility at enhancers and promoters that were tightly coupled to transcript abundance. Multi-modal integration of histone modifications (CUT&Tag and CUT&RUN), promoter-enhancer interactions (Capture-C) and high-order chromatin structure (Hi-C) extended these initial observations. This dataset reveals a diverse chromatin landscape with region-specific regulatory mechanisms and genomic interactions in distinct neurogenic regions of the embryonic mouse brain and represents an extensive public resource of a ‘ground truth’ epigenomic landscape at this critical stage of neurogenesis.
Project description:While comparative genetic analysis has been performed between distinct regions of the embryonic forebrain, a comprehensive characterization of differential epigenomic organization has not been performed. We collected single-cell chromatin accessibility profiles from four distinct neurogenic regions of the embryonic mouse forebrain using single nuclei ATAC-Seq (snATAC-Seq). We identified thousands of differentially accessible peaks, many restricted to distinct progenitor cell types or brain regions. We integrated snATAC-Seq and single cell transcriptome data to characterize changes of chromatin accessibility at enhancers and promoters that were tightly coupled to transcript abundance. Multi-modal integration of histone modifications (CUT&Tag and CUT&RUN), promoter-enhancer interactions (Capture-C) and high-order chromatin structure (Hi-C) extended these initial observations. This dataset reveals a diverse chromatin landscape with region-specific regulatory mechanisms and genomic interactions in distinct neurogenic regions of the embryonic mouse brain and represents an extensive public resource of a ‘ground truth’ epigenomic landscape at this critical stage of neurogenesis.
Project description:While comparative genetic analysis has been performed between distinct regions of the embryonic forebrain, a comprehensive characterization of differential epigenomic organization has not been performed. We collected single-cell chromatin accessibility profiles from four distinct neurogenic regions of the embryonic mouse forebrain using single nuclei ATAC-Seq (snATAC-Seq). We identified thousands of differentially accessible peaks, many restricted to distinct progenitor cell types or brain regions. We integrated snATAC-Seq and single cell transcriptome data to characterize changes of chromatin accessibility at enhancers and promoters that were tightly coupled to transcript abundance. Multi-modal integration of histone modifications (CUT&Tag and CUT&RUN), promoter-enhancer interactions (Capture-C) and high-order chromatin structure (Hi-C) extended these initial observations. This dataset reveals a diverse chromatin landscape with region-specific regulatory mechanisms and genomic interactions in distinct neurogenic regions of the embryonic mouse brain and represents an extensive public resource of a ‘ground truth’ epigenomic landscape at this critical stage of neurogenesis.
Project description:We describe Hi-C, a method that probes the three-dimensional architecture of whole genomes by coupling proximity-based ligation with massively parallel sequencing. We constructed spatial proximity maps of the human genome with Hi-C at a resolution of 1Mb. These maps confirm the presence of chromosome territories and the spatial proximity of small, gene-rich chromosomes. We identified an additional level of genome organization that is characterized by the spatial segregation of open and closed chromatin to form two genome-wide compartments. At the megabase scale, the chromatin conformation is consistent with a fractal globule, a knot-free conformation that enables maximally dense packing while preserving the ability to easily fold and unfold any genomic locus. The fractal globule is distinct from the more commonly used globular equilibrium model. Our results demonstrate the power of Hi-C to map the dynamic conformations of whole genomes. The processed heatmap data, showing the number of read pairs corresponding to particular locus pairs in the genome, are linked to the Series record below. The processed eigenvector data used to generate the heatmaps are linked to the Series record below. Additional DNAseI and ChIP-Seq data tracks were used in the paper, and are available at the UCSC browser (http://genome.ucsc.edu/) DNAseI: wgEncodeUwDnaseSeqRawSignalRep2K562 wgEncodeUwDnaseSeqRawSignalRep2Gm06990 ChIP-Seq: wgEncodeBroadChipSeqSignalGm12878H3k36me3 wgEncodeBroadChipSeqSignalGm12878H3k27me3 Interaction maps in 2 different cell types.
Project description:Emerging evidence suggests that chromatin adopts a non-random three-dimensional (3D) topology and that the organization of genes into structural hubs and domains affects their transcriptional status. How chromatin conformation changes in diseases such as cancer is poorly understood. Moreover, how oncogenic transcription factors, which bind to thousands of sites across the genome, influence gene regulation by globally altering the topology of chromatin requires further investigation. To address these questions, we performed unbiased high-resolution mapping of intra- and inter-chromosome interactions upon over-expression of ERG, an oncogenic transcription factor frequently over-expressed in prostate cancer as a result of a gene fusion. By integrating data from genome-wide chromosome conformation capture (Hi-C), ERG binding and gene expression, we demonstrate that oncogenic transcription factor over-expression is associated with global, reproducible and functionally coherent changes in chromatin organization. The results presented here have broader implications, as genomic alterations in other cancer types frequently give rise to aberrant transcription factor expression e.g., EWS-FLI1, c-Myc, n-Myc, PML-RARα. We used stable isogenic, normal benign prostate epithelial cell lines (RWPE1) that differ with respect to ERG3 over-expression. To test whether ERG over-expression is associated with global changes in chromatin structure, we performed unbiased chromatin interaction mapping using the Hi-C technique from both RWPE1-ERG and RWPE1-GFP cells, with biological replicates. Successful fill-in and ligation were determined as previously reported by testing for a known interaction between two distant genomic loci located on chromosome 6. The Hi-C libraries were paired-end sequenced using an Illumina GAIIx platform. Following alignment to the human genome (hg18) and filtering to remove un-ligated and self-ligated DNA, we identified intra-chromosomal (or cis-) and inter-chromosomal (or trans-) interactions in both RWPE1 cell lines. To characterize ERG binding and ERG-mediated gene expression changes in these cells, we performed chromatin-immunoprecipitation combined with high-throughput sequencing (ChIP-seq) and RNA sequencing (RNA-seq). ERG was bound to 6,398 sites in RPWE1-ERG cells. Based on paired-end RNA-seq data from both cell lines, 1,266 genes were differentially expressed between RWPE1-ERG and RWPE1-GFP cell lines.