Homo sapiens
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA113053 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:We sought to identify nuclease-hypersensitive sites and to quantify nucleosome positions in an effort to identify cis-regulatory elements in the protozoan parasite Leishmania major. Using micrococcal nuclease digestion of chromatin (MNAse-seq), we report that few nuclease hypersensitive sites are present within the presumed regions of RNA polymerase II-mediated transcription initiation, and that similar numbers of nuclease hypersensitive sites were found in control datasets. However, utilizing an independent approach (FAIRE), we observe that a heterogeneous population of nuclease hypersensitive sites are present in and around these regions, and that nucleosomes within these regions are susceptible to MNAse overdigestion.
2020-03-31 | GSE60846 | GEO
Project description:Cellular memory is maintained at the Drosophila homeotic gene clusters by cis-regulatory elements who mechanism of action is unknown. We have examined chromatin dynamics in the Drosophila genome by measuring histone turnover levels at high resolution. Surprisingly, homeotic gene clusters display characteristic histone turnover profiles with conspicuous peaks at boundaries of cis-regulatory domains superimposed over regions of very low turnover. Peaks of histone turnover precisely correspond to nuclease hypersensitive sites for epigenetic silencing proteins. Our results suggest that epigenetic regulation is facilitated by histone turnover, which maintains continuous accessibility ov cis-regulatory DNA. Keywords: Chromatin affinity-purification on microarray
2007-03-01 | GSE6234 | GEO
Project description:This track is produced as part of the mouse ENCODE Project. This track shows DNaseI sensitivity measured genome-wide in mouse tissues and cell lines using the Digital DNaseI methodology (see below), and DNaseI hypersensitive sites. DNaseI has long been used to map general chromatin accessibility and DNaseI hypersensitivity is a universal feature of active cis-regulatory sequences. The use of this method has led to the discovery of functional regulatory elements that include enhancers, insulators, promotors, locus control regions and novel elements. For each experiment (tissue/cell type) this track shows DNaseI sensitivity as a continuous function using sequencing tag density (Signal), and discrete loci of DNaseI sensitive zones (HotSpots) and hypersensitive sites (Peaks). For data usage terms and conditions, please refer to http://www.genome.gov/27528022 and http://www.genome.gov/Pages/Research/ENCODE/ENCODEDataReleasePolicyFinal2008.pdf Cells were grown according to the approved ENCODE cell culture protocols (http://hgwdev.cse.ucsc.edu/ENCODE/protocols/cell/mouse). Fresh tissues were harvested from mice and the nuclei prepared according to the tissue appropriate protocol (http://hgwdev.cse.ucsc.edu/ENCODE/protocols/cell/mouse). Digital DNaseI was performed by DNaseI digestion of intact nuclei, isolating DNaseI 'double-hit' fragments as described in Sabo et al. (2006), and direct sequencing of fragment ends (which correspond to in vivo DNaseI cleavage sites) using the Illumina IIx (and Illumina HiSeq by early 2011) platform (36 bp reads). Uniquely mapping high-quality reads were mapped to the genome using the bowtie aligner. DNaseI sensitivity is directly reflected in raw tag density, which is shown in the track as density of tags mapping within a 150 bp sliding window (at a 20 bp step across the genome). DNaseI sensitive zones (HotSpots) were identified using the HotSpot algorithm described in Sabo et al. (2004). 1.0% false discovery rate thresholds (FDR 0.01) were computed for each cell type by applying the HotSpot algorithm to an equivalent number of random uniquely mapping 36mers. DNaseI hypersensitive sites (DHSs or Peaks) were identified as signal peaks within FDR 1.0% hypersensitive zones using a peak-finding algorithm (I-max).
2012-10-03 | E-GEOD-37074 | biostudies-arrayexpress
Project description:This data was generated by ENCODE. If you have questions about the data, contact the submitting laboratory directly (Richard Sandstrom mailto:sull@u.washington.edu). If you have questions about the Genome Browser track associated with this data, contact ENCODE (mailto:genome@soe.ucsc.edu). This track is produced as part of the ENCODE Project. This track shows DNaseI sensitivity measured genome-wide in different cell lines using the Digital DNaseI methodology (see below), and DNaseI hypersensitive sites. DNaseI has long been used to map general chromatin accessibility and DNaseI hypersensitivity is a universal feature of active cis-regulatory sequences. The use of this method has led to the discovery of functional regulatory elements that include enhancers, insulators, promotors, locus control regions and novel elements. For each experiment (cell type) this track shows DNaseI sensitivity as a continuous function using sequencing tag density (Raw Signal), and discrete loci of DNaseI sensitive zones (HotSpots) and hypersensitive sites (Peaks)." For data usage terms and conditions, please refer to http://www.genome.gov/27528022 and http://www.genome.gov/Pages/Research/ENCODE/ENCODEDataReleasePolicyFinal2008.pdf Cells were grown according to the approved ENCODE cell culture protocols. Digital DNaseI was performed by DNaseI digestion of intact nuclei, isolating DNaseI 'double-hit' fragments as described in Sabo et al. (2006), and direct sequencing of fragment ends (which correspond to in vivo DNaseI cleavage sites) using the Solexa platform (36 bp reads). Uniquely mapping high-quality reads were mapped to the genome. DNaseI sensitivity is directly reflected in raw tag density (Raw Signal), which is shown in the track as density of tags mapping within a 150 bp sliding window (at a 20 bp step across the genome). DNaseI sensitive zones (HotSpots) were identified using the HotSpot algorithm described in Sabo et al. (2004). 1.0% false discovery rate thresholds (FDR 0.01) were computed for each cell type by applying the HotSpot algorithm to an equivalent number of random uniquely mapping 36mers. DNaseI hypersensitive sites (DHSs or Peaks) were identified as signal peaks within FDR 1.0% hypersensitive zones using a peak-finding algorithm.
2011-06-03 | E-GEOD-29692 | biostudies-arrayexpress
Project description:This track is produced as part of the mouse ENCODE Project. This track shows DNaseI sensitivity measured genome-wide in mouse tissues and cell lines using the Digital DNaseI methodology (see below), and DNaseI hypersensitive sites. DNaseI has long been used to map general chromatin accessibility and DNaseI hypersensitivity is a universal feature of active cis-regulatory sequences. The use of this method has led to the discovery of functional regulatory elements that include enhancers, insulators, promotors, locus control regions and novel elements. For each experiment (tissue/cell type) this track shows DNaseI sensitivity as a continuous function using sequencing tag density (Signal), and discrete loci of DNaseI sensitive zones (HotSpots) and hypersensitive sites (Peaks). For data usage terms and conditions, please refer to http://www.genome.gov/27528022 and http://www.genome.gov/Pages/Research/ENCODE/ENCODEDataReleasePolicyFinal2008.pdf
2012-10-03 | GSE37074 | GEO
Project description:Nucleosome positioning dictates the DNA accessibility for regulatory proteins, and thus is critical for gene expression and regulation. It has been well documented that only a subset of nucleosomes are reproducibly positioned (phased) in eukaryotic genomes. The most prominent example of phased nucleosomes is the context of genes, where phased nucleosomes flank the transcriptional starts sites (TSSs). It is unclear, however, what factors influence nucleosome phasing in regions that are not close to genes. We performed a combinational mapping of nucleosome positioning and DNase I hypersensitive sites (DHSs) across the rice genome. We discovered that DHSs located in a variety of contexts, both genic and intergenic, were flanked by strongly phased nucleosome arrays. Our results support the barrier model for nucleosome organization as a general feature of eukaryote genomes, including plant genomes, and not limited to TSSs. Specifically, regions bound with regulatory proteins, including intergenic regions, can serve as barriers that organize phased nucleosome arrays on both sides. Our results also suggest that rice DHSs often span a single, phased nucleosome, similar to the H2A.Z-containing nucleosomes observed in DHSs in the human genome. We propose that genome-wide nucleosome positioning in the eukaryotic genomes is orchestrated by genomic regions associated with regulatory proteins. Rice chromatin was digested by micrococcal nuclease (MNase) into mono-nucleosome size. Mono-nucleosomal DNA was isolated and sequenced (MNase-seq) using Illumina sequencing platforms. We obtained a total of 38 million (M) single-end reads from our first MNase-seq experiment and mapped ~26 M to unique positions in the rice genome. We also conducted pair-end sequencing of an independent MNase-seq library, obtained 274 M paired-end reads, and mapped ~231 M read pairs to unique positions in the rice genome.We applied a strategy of combinational mapping of nucleosome positioning and DHSs (GSE26610) to examine whether nucleosome positioning is associated with all cis-regulatory elements in the rice genome. All datasets used in the analysis were developed using rice leaf tissue in the same developmental stage
2014-05-01 | E-GEOD-53027 | biostudies-arrayexpress
Project description:Mapping cis-regulatory elements in the midgestation mouse placenta
| PRJNA744555 | ENA
Project description:Cis-regulatory sequences are the key elements for understanding global, context-dependent gene expression program in response to environmental challenges. Because of uncertainty in their location relative to gene, nuclease hypersensitivity has been used as the robust experimental approach for identifying these regulatory elements. We used oligonucleotide array chip and 454 sequencing platform to map the nuclease-hypersensitive sites (NHSS) in MCF-7 cell genome. Small DNA fragments released after very mild micrococcal nuclease treatment were found to be highly associated with promoter, transcription factor binding sites, regulatory potential and gene expression. In addition, sequencing data reveal three classes of novel NHSS not reported previously: 1) those containing regular repeat of NHSS (RNHSS), 2) those containing mitochondria sequence inserts (MNHSS), and 3) those containing highly clustered NHSS (CNHSS). Blatting analysis shows that these novel NHSS are highly associated with genome rearrangements and creation of novel genes during primate genome evolution. Repeated genes/ESTs in RNHSS are often widely expressed in human adult and fetal tissues. The majority of NHSS is sensitive to alpha-amanitin treatment with the exception of RNHSS and some genes with amanitin-insensitive expression. We suggest that study of these novel classes of NHSS may be crucial for understanding primate genome evolution.
2008-09-05 | GSE12650 | GEO
Project description:Unraveling cis-regulatory elements by mapping structural changes in mRNAs
| PRJNA396539 | ENA
Project description:The functional genome of agronomically important plant species remains largely unexplored, yet presents a virtually untapped resource for targeted crop improvement. Functional elements and regulatory DNA revealed through chromatin accessibility maps can be harnessed for manipulating gene expression to subtle phenotypic outputs that enhance productivity in specific environments. Here, we present a genome-wide view of accessible chromatin and nucleosome occupancy at a very early stage in the development of both pollen- and grain-bearing inflorescences of the important cereal crop maize (Zea mays), using an assay for differential sensitivity of chromatin to micrococcal nuclease (MNase) digestion. Results showed that in these largely undifferentiated tissues, approximately 1.5-4 percent of the genome is accessible, with the majority of MNase hypersensitive sites marking proximal promoters but also 3’ flanks of maize genes. This approach mapped regulatory elements to footprint-level resolution, and through integration of complementary transcriptome and transcription factor occupancy data, we annotated regulatory factors such as combinatorial motifs and long non-coding RNAs that potentially contribute to organogenesis in maize inflorescence development, including tissue-specific regulation between male and female structures. Finally, genome-wide association studies for inflorescence architecture traits based only on functional regions delineated by MNase hypersensitivity, revealed new SNP-trait associations in known regulators of inflorescence development. These analyses provide a first look into the cis-regulatory landscape during inflorescence differentiation in a major cereal crop, which ultimately shapes architecture and influences yield potential.
2020-06-05 | GSE136685 | GEO