The spatio-temporal program of DNA replication is driven by specific epigenetic signatures in human cells
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
SUBMITTER: Jean-Charles Cadoret
PROVIDER: E-GEOD-46189 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
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Project description:Short nascent strands purification coupled to next-generation sequencing allowed us to identify replication origins on human genome in an extensive way, by mapping replication origins in 4 different cell types, IMR-90 fibroblasts, hESC H9 cells, iPSC Th Cl-4 cells and HeLa cells. We demonstrated the existence of a cell type-specific reprogrammable signature of the cell identity revealed by specific efficiencies of conserved origin positions and not by the selection of cell-type specific subsets of origins. 4 different cell types were analyzed. For each cell types, 2 different biological replicates of short nascent strands at replication origins were purified. Each SNS sample was sequencing at least one time.
2012-07-01 | E-GEOD-37757 | biostudies-arrayexpress
Project description:At every cell cycle, faithful inheritance of metazoan genomes requires the concerted activation of thousands of DNA replication origins. However, which genetic and chromatin features define metazoan replication start sites remains largely unknown. Here, we delineate the origin repertoire of the Drosophila genome at high resolution. We address the role of origin-proximal G-quadruplexes and show their ability to transiently stall replication forks in vivo. We dissect the chromatin configuration of replication origins and identify a rich spatial organization of chromatin features at initiation sites. DNA shape and chromatin configurations, not strict sequence specificity, mark and predict replication origins in higher eukaryotes. We further examine the link between transcription and origin firing and reveal that modulation of origin activity across cell types is intimately linked to cell-type-specific transcriptional programs. Our study unravels conserved origin features and provides unique insights into the relationship between DNA topology, chromatin, transcription and replication initiation across metazoa. Our dataset consists of SNS-Seq profiles in Drosophila S2 and Bg3 cells. Small nascent leading strands (SNS) have been purified with an enhanced sensitivity SNS purification protocol. For standard SNS-Seq experiments (from pooled gradient fractions, denoted as "pool"), SNS were purified from two biological replicates. For single-fraction SNS-Seq experiments, two libraries were prepared for each fraction. The genomic coordinates of S2 and Bg3 replication origins are also provided.
2015-04-23 | E-GEOD-65692 | biostudies-arrayexpress
Project description:The goal of this study was to analyze global gene expression in specific populations of somatosensory neurons in the periphery, including major, non-overlapping populations that include nociceptors, pruriceptors, and prorioceptors. The mammalian somatosensory nervous system encodes the perception of specific environmental stimuli. The dorsal root ganglion (DRG) contains distinct somatosensory neuron subtypes that innervate diverse peripheral tissues, mediating the detection of thermal, mechanical, proprioceptive, pruriceptive, and nociceptive stimuli. We purified discrete subtypes of mouse DRG somatosensory neurons by flow cytometry using fluorescently labeled mouse lines (SNS-Cre/TdTomato, Parv-Cre/TdTomato) in combination with Isolectin B4-FITC surface staining (IB4). This allowed identification of transcriptional differences between these major populations, revealing enrichment of voltage-gated ion channels, TRP channels, G-protein coupled receptors, transcription factors, and other functionally important classes of genes within specific somatosensory neuron subsets. SNS-Cre mice were bred with Rosa26-TdTomato mice to generate SNS-Cre/TdTomato reporter mice. Parv-Cre mice were bred with Rosa26-TdTomato mice to generate Parv-Cre/TdTomato mice. Isolectin B4-FITC was used to stain the surface of SNS-Cre/TdTomato reporter mice. We used these strategies of fluorescent labeling to purify distinct murine sensory neuron subsets from the dorsal root ganglia (DRG) by fluorescence activated cell sorting (FACS). Neurons were sorted directly in Qiazol for total RNA extraction and microarray analysis. Whole DRG tissue was also included for transcriptome analysis to compare with purified neuronal populations.
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Project description:modENCODE_submission_2753 This submission comes from a modENCODE project of David MacAlpine. For full list of modENCODE projects, see http://www.genome.gov/26524648 Project Goal: We will precisely identify sequence elements that direct DNA replication by using chromatin immunoprecipitation of known replication initiation complexes. These experiments will be conducted in multiple cell types and developmental tissues. For data usage terms and conditions, please refer to http://www.genome.gov/27528022 and http://www.genome.gov/Pages/Research/ENCODE/ENCODEDataReleasePolicyFinal2008.pdf Keywords: CHIP-seq EXPERIMENT TYPE: CHIP-seq. BIOLOGICAL SOURCE: Cell Line: S2-DRSC; Tissue: embryo-derived cell-line; Developmental Stage: late embryonic stage; Sex: Male; EXPERIMENTAL FACTORS: Antibody dORC2
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Project description:modENCODE_submission_2754 This submission comes from a modENCODE project of David MacAlpine. For full list of modENCODE projects, see http://www.genome.gov/26524648 Project Goal: We will precisely identify sequence elements that direct DNA replication by using chromatin immunoprecipitation of known replication initiation complexes. These experiments will be conducted in multiple cell types and developmental tissues. For data usage terms and conditions, please refer to http://www.genome.gov/27528022 and http://www.genome.gov/Pages/Research/ENCODE/ENCODEDataReleasePolicyFinal2008.pdf Keywords: CHIP-seq EXPERIMENT TYPE: CHIP-seq. BIOLOGICAL SOURCE: Cell Line: ML-DmBG3-c2; Tissue: CNS-derived cell-line; Developmental Stage: third instar larval stage; Genotype: y v f mal; Sex: Unknown; EXPERIMENTAL FACTORS: Antibody dORC2
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