Saccharomyces cerevisiae
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA150155 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:H3 ChIP and input DNA were hybridized to Affymetrix GeneChip S. cerevisiae Tiling 1.0R Array Genome-wide mapping of nucleosomes generated by micrococcal nuclease (MNase) suggests that yeast promoter and terminator regions are very depleted of nucleosomes, predominantly because their DNA sequences intrinsically disfavor nucleosome formation. However, MNase has strong DNA sequence specificity that favors cleavage at promoters and terminators and accounts for some of the correlation between occupancy patterns of nucleosomes assembled in vivo and in vitro. Using an improved method for measuring nucleosome occupancy in vivo that does not involve MNase, we confirm that promoter regions are strongly depleted of nucleosomes, but find that terminator regions are much less depleted than expected. Unlike at promoter regions, nucleosome occupancy at terminators is strongly correlated with the orientation of and distance to adjacent genes. In addition, nucleosome occupancy at terminators is strongly affected by growth conditions, indicating that it is not primarily determined by intrinsic histone-DNA interactions. Rapid removal of RNA polymerase II (Pol II) causes increased nucleosome occupancy at terminators, strongly suggesting a transcription-based mechanism of nucleosome depletion. However, the distinct behavior of terminator regions and their corresponding coding regions suggests that nucleosome depletion at terminators is not simply associated with passage of Pol II, but rather involves a distinct mechanism linked to 3’ end formation.
2010-09-21 | GSE23778 | GEO
Project description:MNase-seq Experiments from Calorie Restricted and Non-Restricted Yeast from WT, ISW2DEL and ISW2K215R strains We used MNase-seq to study genome-wide nucleosome positions under Calorie Restricted and Non-restricted Saccharomyces cerevisiae
2014-09-15 | E-GEOD-53718 | biostudies-arrayexpress
Project description:The structural complexity of nucleosomes underlies their functional versatility. Here we report a new type of complexity – nucleosome fragility, manifested as high sensitivity to micrococcal nuclease, in contrast to the common presumption that nucleosomes are similar in resistance to MNase digestion. Using differential MNase digestion of chromatin and high-throughput sequencing, we have identified a special group of nucleosomes termed fragile nucleosomes throughout the yeast genome, nearly one thousand of which are at previously determined “nucleosome free” loci. Nucleosome fragility is broadly implicated in multiple chromatin processes, including transcription, translocation and replication, in correspondence to specific physiological states of cells. In the environmental-stress-response genes, the presence of fragile nucleosomes prior to the occurrence of environmental changes suggests that nucleosome fragility poises genes for swift up-regulation in response to the environmental changes. We propose that nucleosome fragility underscores distinct functional statuses of the chromatin and provides a new dimension for portraying the landscape of genome organization. Comparing nucleosome occupancy under different MNase digestion levels and growth conditions.
2011-01-24 | E-GEOD-26412 | biostudies-arrayexpress
Project description:Mapping of nucleosomes, the basic DNA packaging unit in eukaryotes, is fundamental for understanding genome regulation as nucleosomes modulate DNA access by their positioning along the genome. A cell population nucleosome map requires two observables: nucleosome positions along the DNA (“Where?”) and nucleosome occupancies across the population (“In how many cells?”). All available genome-wide nucleosome mapping techniques are yield methods as they score either nucleosomal (e.g., MNase-seq, chemical cleavage-seq) or non-nucleosomal (e.g., ATAC-seq) DNA but lose track of the total DNA population for each genomic region. Therefore, they only provide nucleosome positions and maybe compare relative occupancies between positions but cannot measure absolute nucleosome occupancy, which is the fraction of all DNA molecules occupied at a given position and time by a nucleosome. Here, we established two orthogonal and thereby crossvalidating approaches to measure absolute nucleosome occupancy across the Saccharomyces cerevisiae genome via restriction enzymes and DNA methyltransferases. The resulting high-resolution (9 bp) map shows uniform absolute occupancies. Most nucleosome positions are occupied in most cells: 97% of all nucleosomes called by chemical cleavage-seq have a mean absolute occupancy of 90 ± 6% (± SD). Depending on nucleosome position calling procedures, there are 57-60,000 nucleosomes per yeast cell. The few low absolute occupancy nucleosomes do not correlate with highly transcribed gene bodies, but with increased presence of the nucleosome-evicting RSC chromatin remodeling complex there and are enriched upstream of highly transcribed or regulated genes. Our work provides a quantitative method and reference frame in absolute terms for future chromatin studies.
2019-11-27 | GSE141051 | GEO
Project description:Mapping of nucleosomes, the basic DNA packaging unit in eukaryotes, is fundamental for understanding genome regulation as nucleosomes modulate DNA access by their positioning along the genome. A cell population nucleosome map requires two observables: nucleosome positions along the DNA (“Where?”) and nucleosome occupancies across the population (“In how many cells?”). All available genome-wide nucleosome mapping techniques are yield methods as they score either nucleosomal (e.g., MNase-seq, chemical cleavage-seq) or non-nucleosomal (e.g., ATAC-seq) DNA but lose track of the total DNA population for each genomic region. Therefore, they only provide nucleosome positions and maybe compare relative occupancies between positions but cannot measure absolute nucleosome occupancy, which is the fraction of all DNA molecules occupied at a given position and time by a nucleosome. Here, we established two orthogonal and thereby crossvalidating approaches to measure absolute nucleosome occupancy across the Saccharomyces cerevisiae genome via restriction enzymes and DNA methyltransferases. The resulting high-resolution (9 bp) map shows uniform absolute occupancies. Most nucleosome positions are occupied in most cells: 97% of all nucleosomes called by chemical cleavage-seq have a mean absolute occupancy of 90 ± 6% (± SD). Depending on nucleosome position calling procedures, there are 57-60,000 nucleosomes per yeast cell. The few low absolute occupancy nucleosomes do not correlate with highly transcribed gene bodies, but with increased presence of the nucleosome-evicting RSC chromatin remodeling complex there and are enriched upstream of highly transcribed or regulated genes. Our work provides a quantitative method and reference frame in absolute terms for future chromatin studies.
2019-11-27 | GSE141043 | GEO
Project description:Mapping of nucleosomes, the basic DNA packaging unit in eukaryotes, is fundamental for understanding genome regulation as nucleosomes modulate DNA access by their positioning along the genome. A cell population nucleosome map requires two observables: nucleosome positions along the DNA (“Where?”) and nucleosome occupancies across the population (“In how many cells?”). All available genome-wide nucleosome mapping techniques are yield methods as they score either nucleosomal (e.g., MNase-seq, chemical cleavage-seq) or non-nucleosomal (e.g., ATAC-seq) DNA but lose track of the total DNA population for each genomic region. Therefore, they only provide nucleosome positions and maybe compare relative occupancies between positions but cannot measure absolute nucleosome occupancy, which is the fraction of all DNA molecules occupied at a given position and time by a nucleosome. Here, we established two orthogonal and thereby crossvalidating approaches to measure absolute nucleosome occupancy across the Saccharomyces cerevisiae genome via restriction enzymes and DNA methyltransferases. The resulting high-resolution (9 bp) map shows uniform absolute occupancies. Most nucleosome positions are occupied in most cells: 97% of all nucleosomes called by chemical cleavage-seq have a mean absolute occupancy of 90 ± 6% (± SD). Depending on nucleosome position calling procedures, there are 57-60,000 nucleosomes per yeast cell. The few low absolute occupancy nucleosomes do not correlate with highly transcribed gene bodies, but with increased presence of the nucleosome-evicting RSC chromatin remodeling complex there and are enriched upstream of highly transcribed or regulated genes. Our work provides a quantitative method and reference frame in absolute terms for future chromatin studies.
2019-11-27 | GSE141056 | GEO
Project description:Mapping of nucleosomes, the basic DNA packaging unit in eukaryotes, is fundamental for understanding genome regulation as nucleosomes modulate DNA access by their positioning along the genome. A cell population nucleosome map requires two observables: nucleosome positions along the DNA (“Where?”) and nucleosome occupancies across the population (“In how many cells?”). All available genome-wide nucleosome mapping techniques are yield methods as they score either nucleosomal (e.g., MNase-seq, chemical cleavage-seq) or non-nucleosomal (e.g., ATAC-seq) DNA but lose track of the total DNA population for each genomic region. Therefore, they only provide nucleosome positions and maybe compare relative occupancies between positions but cannot measure absolute nucleosome occupancy, which is the fraction of all DNA molecules occupied at a given position and time by a nucleosome. Here, we established two orthogonal and thereby crossvalidating approaches to measure absolute nucleosome occupancy across the Saccharomyces cerevisiae genome via restriction enzymes and DNA methyltransferases. The resulting high-resolution (9 bp) map shows uniform absolute occupancies. Most nucleosome positions are occupied in most cells: 97% of all nucleosomes called by chemical cleavage-seq have a mean absolute occupancy of 90 ± 6% (± SD). Depending on nucleosome position calling procedures, there are 57-60,000 nucleosomes per yeast cell. The few low absolute occupancy nucleosomes do not correlate with highly transcribed gene bodies, but with increased presence of the nucleosome-evicting RSC chromatin remodeling complex there and are enriched upstream of highly transcribed or regulated genes. Our work provides a quantitative method and reference frame in absolute terms for future chromatin studies.
2019-11-27 | GSE141049 | GEO
Project description:MNase-seq Experiments from Calorie Restricted and Non-Restricted Yeast from WT, ISW2DEL and ISW2K215R strains
2014-09-15 | GSE53718 | GEO
Project description:The structural complexity of nucleosomes underlies their functional versatility. Here we report a new type of complexity – nucleosome fragility, manifested as high sensitivity to micrococcal nuclease, in contrast to the common presumption that nucleosomes are similar in resistance to MNase digestion. Using differential MNase digestion of chromatin and high-throughput sequencing, we have identified a special group of nucleosomes termed fragile nucleosomes throughout the yeast genome, nearly one thousand of which are at previously determined “nucleosome free” loci. Nucleosome fragility is broadly implicated in multiple chromatin processes, including transcription, translocation and replication, in correspondence to specific physiological states of cells. In the environmental-stress-response genes, the presence of fragile nucleosomes prior to the occurrence of environmental changes suggests that nucleosome fragility poises genes for swift up-regulation in response to the environmental changes. We propose that nucleosome fragility underscores distinct functional statuses of the chromatin and provides a new dimension for portraying the landscape of genome organization.
2011-01-24 | GSE26412 | GEO
