Nucleosome profiles for mammalian tissues [Mnase-Seq]
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus Sus scrofa Homo sapiens Macaca mulatta Tupaia belangeri
PROVIDER: GSE106578 | GEO | 2018/08/07
REPOSITORIES: GEO
Similar Datasets
Project description:Chromatin structure affects gene splicing and nucleosome as the basic packaged unit is associated with exon recognition. But little is known about the function of nucleosome occupancy in the process of exon origination. Here we performed MNase-seq to obtain genome-wide nucleosome profiles for several tissues of human, rhesus monkey, treeshrew, mouse and pig. At the first time we found conserved nucleosome profile for different tissues. By combining RNA-seq data of each species, we traced the nucleosome occupancy changes of human new exons. Surprisingly, we found nucleosomes were higher occupied before exon formation. And this pre-occupancy contributed to the formation of exon-intron GC difference and maintain splice site strength. Thus we proposed a preadaption model for the function of nucleosome occupancy in human exons origination.
2018-08-07 | GSE106577 | GEO
Project description:Nucleosomes compact and regulate access to DNA in the nucleus, and are composed of approximately 147 bases of DNA wrapped around a histone octamer. Here we report a genome-wide nucleosome positioning analysis of Arabidopsis thaliana utilizing massively parallel sequencing of mononucleosomes. By combining this data with profiles of DNA methylation at single base resolution, we identified ten base periodicities in the DNA methylation status of nucleosome-bound DNA and found that nucleosomal DNA was more highly methylated than flanking DNA. These results suggest that nucleosome positioning strongly influences DNA methylation patterning throughout the genome and that DNA methyltransferases preferentially target nucleosome-bound DNA. We also observed similar trends in human nucleosomal DNA suggesting that the relationships between nucleosomes and DNA methyltransferases are conserved. Finally, as has been observed in animals, nucleosomes were highly enriched on exons, and preferentially positioned at intron-exon and exon-intron boundaries. RNA Pol II was also enriched on exons relative to introns, consistent with the hypothesis that nucleosome positioning regulates Pol II processivity. We also found that DNA methylation enriched on exons, consistent with the targeting of DNA methylation to nucleosomes.
2010-05-29 | GSE21821 | GEO
Project description:Nucleosomes compact and regulate access to DNA in the nucleus, and are composed of approximately 147 bases of DNA wrapped around a histone octamer. Here we report a genome-wide nucleosome positioning analysis of Arabidopsis thaliana utilizing massively parallel sequencing of mononucleosomes. By combining this data with profiles of DNA methylation at single base resolution, we identified ten base periodicities in the DNA methylation status of nucleosome-bound DNA and found that nucleosomal DNA was more highly methylated than flanking DNA. These results suggest that nucleosome positioning strongly influences DNA methylation patterning throughout the genome and that DNA methyltransferases preferentially target nucleosome-bound DNA. We also observed similar trends in human nucleosomal DNA suggesting that the relationships between nucleosomes and DNA methyltransferases are conserved. Finally, as has been observed in animals, nucleosomes were highly enriched on exons, and preferentially positioned at intron-exon and exon-intron boundaries. RNA Pol II was also enriched on exons relative to introns, consistent with the hypothesis that nucleosome positioning regulates Pol II processivity. We also found that DNA methylation enriched on exons, consistent with the targeting of DNA methylation to nucleosomes. Genomic DNA from Arabidopsis thaliana was MNase digested, size selected and sequenced. Genomic DNA associated with H3 was isolated using ChIP and sequenced. Genomic DNA from human HSF1 embryonic stem cells was bisulfite converted and sequenced.
2010-05-29 | E-GEOD-21821 | biostudies-arrayexpress
Project description:MNase-Seq for nucleosome occupancy
| PRJNA649224 | ENA
Project description:Open chromatin provides access to a wide spectrum of DNA binding proteins for DNA metabolism processes such as transcription, repair, recombination, and replication. In this regard, open chromatin profiling has been widely used to identify the location of regulatory regions, including promoters, enhancers, insulators, silencers, replication origins, and recombination hotspots. Regulatory DNA elements are made accessible by nucleosome-depeleted states. Thus, nucleosome remodelling and modification should be intimately coupled with open chromatin formation and regulation. However, our knowledge of nucleosome regulation is largely limited to promoter regions, which comprise only a subset of all regulatory loci in the genome. In order to examine nucleosome patterns in open chromatin regions, we performed micrococcal nuclease (MNase) sequencing for a laboratory strain of yeast. Nucleosome occupancy profiled by Micrococcal nuclease (MNase) digestion
2013-01-06 | E-GEOD-34923 | biostudies-arrayexpress
Project description:DNA are packaged into nucleosomes and chromatin. We performed incomplete MNase digestion of chromatin to identify nucleosome-free regions that may indicate active promoters and regulatory regions. Additionally, HpaII digestion was performed which cleaves CCGG sites when the internal C remains unmodified. The hypomethylation state and nuclease sensitivity of the chromatin are indicators of transcription regulatory regions.
2015-02-25 | E-MTAB-1958 | biostudies-arrayexpress
Project description:H2B mono-ubiquitylation is required for multiple methylations of both H3K4 and H3K79 and has been implicated in gene expression from yeast to human. However, molecular crosstalk between H2BUb1 and other modifications, especially H3K4 and H3K79 methylations, remains unclear in vertebrates. To understand the functional role of H2BUb1, genome-wide histone modification patterns were measured in human cells. This study proposes dual roles of H2BUb1 that are both H3 methylation dependent and independent. First, H2BUb1 is a 5'-enriched active transcription mark and is co-occupied with H3K79 methylations in actively transcribed regions. Importantly, this study found a unique role of H2BUb1 in chromatin architecture independent of histone H3 methylations. H2BUb1 is well positioned in exon-intron boundaries of highly expressed exons and is specifically enriched in 5'-biased exons. Furthermore, H2BUb1 demonstrates increased occupancy in skipped exons compared to flanking exons for the human and mouse genome. Our findings suggest that a potentiating mechanism links H2BUb1 to both H3K79 methylations in actively transcribed regions and the exon-intron structure of highly expressed exons through the regulation of nucleosome dynamics during transcription elongation. We generated high-throughput sequencing (ChIP-seq) data for genome-wide occupancy of H2BUb1, nucleosome, H3K4me3, H3K36me3, H379me1/2/3, H3Ac, and mRNA in human embryonic carcinoma cells. We performed ChIP-seq for seven different histone modifications, MNase-seq, mRNA-seq (two replications), and inputDNA-seq in NCCIT cell lines (human embryonic carcinoma cell lines). We also performed mRNA-seq for RNF20-siRNA transfected NCCIT cells, where H2BUb1 signals decreased.
2012-03-07 | E-GEOD-25882 | biostudies-arrayexpress
Project description:Transcription profiling of two cancer cell lines: K562 and U937. It has recently been shown that nucleosome distribution, histone modifications and RNA polymerase II (Pol II) occupancy show preferential association with exons ("exon-intron marking"), linking chromatin structure and function to co- transcriptional splicing in a variety of eukaryotes. Previous ChIP-sequencing studies suggested that these marking patterns reflect the nucleosomal landscape. By analyzing ChIP-chip datasets across the human genome in three cell types, we have found that this marking system is far more complex than previously observed. We show here that a range of histone modifications and Pol II are preferentially associated with exons. However, there is noticeable cell-type specificity in the degree of exon marking by histone modifications and, surprisingly, this is also reflected in some histone modifications patterns showing biases towards introns. Exon-intron marking is laid down in the absence of transcription on silent genes, with some marking biases changing or becoming reversed for genes expressed at different levels. Furthermore, the relationship of this marking system with splicing is not simple, with only some histone modifications reflecting exon usage/inclusion, while others mirror patterns of exon exclusion. By examining nucleosomal distributions in all three cell types, we demonstrate that these histone modification patterns cannot solely be accounted for by differences in nucleosome levels between exons and introns. In addition, because of inherent differences between ChIP-chip array and ChIP-sequencing approaches, these platforms report different nucleosome distribution patterns across the human genome. Our findings confound existing views and point to active cellular mechanisms which dynamically regulate histone modification levels and account for exon-intron marking. We believe that these histone modification patterns provide links between chromatin accessibility, Pol II movement and co-transcriptional splicing.
2010-12-03 | E-MTAB-335 | biostudies-arrayexpress
Project description:Whole genome profiling of 4 histone modifications (H3K27me1, H3K27me3,H3K36me1 and H3K36me3) using ChIP-on-chip. It has recently been shown that nucleosome distribution, histone modifications and RNA polymerase II (Pol II) occupancy show preferential association with exons ("exon-intron marking"), linking chromatin structure and function to co- transcriptional splicing in a variety of eukaryotes. Previous ChIP-sequencing studies suggested that these marking patterns reflect the nucleosomal landscape. By analyzing ChIP-chip datasets across the human genome in three cell types, we have found that this marking system is far more complex than previously observed. We show here that a range of histone modifications and Pol II are preferentially associated with exons. However, there is noticeable cell-type specificity in the degree of exon marking by histone modifications and, surprisingly, this is also reflected in some histone modifications patterns showing biases towards introns. Exon-intron marking is laid down in the absence of transcription on silent genes, with some marking biases changing or becoming reversed for genes expressed at different levels. Furthermore, the relationship of this marking system with splicing is not simple, with only some histone modifications reflecting exon usage/inclusion, while others mirror patterns of exon exclusion. By examining nucleosomal distributions in all three cell types, we demonstrate that these histone modification patterns cannot solely be accounted for by differences in nucleosome levels between exons and introns. In addition, because of inherent differences between ChIP-chip array and ChIP-sequencing approaches, these platforms report different nucleosome distribution patterns across the human genome. Our findings confound existing views and point to active cellular mechanisms which dynamically regulate histone modification levels and account for exon-intron marking. We believe that these histone modification patterns provide links between chromatin accessibility, Pol II movement and co-transcriptional splicing.
2010-12-03 | E-MTAB-336 | biostudies-arrayexpress
Project description:Genomes are packaged into nucleosomes whose position and modification state can profoundly influence regulation of gene expression. We have established new ChIP-based high-resolution genome-wide maps of histone acetylation and methylation that take into account changes in nucleosome occupancy at actively transcribed genes. These maps provide a more accurate picture of nucleosome occupancy and the nature of modifications associated with transcriptional activity in this eukaryotic genome. We describe the combination of modifications that occur at the average transcribed gene.
2005-08-25 | E-WMIT-3 | biostudies-arrayexpress