Decoding the protein composition of whole nucleosomes with Nuc-MS
Ontology highlight
ABSTRACT:
INSTRUMENT(S): Q Exactive HF Ultra High Mass Range (Thermo Scientific)
ORGANISM(S): Homo Sapiens (ncbitaxon:9606)
SUBMITTER: 
Neil L Kelleher
PROVIDER: MSV000085238 | MassIVE | Mon Apr 06 13:26:00 BST 2020
REPOSITORIES: MassIVE
Similar Datasets
Project description:Current proteomic approaches disassemble and digest nucleosome particles, blurring readouts of the ‘histone code’. To preserve nucleosome-level information, we developed Nuc-MS, which displays the landscape of histone variants and their post-translational modifications (PTMs) in a single mass spectrum. Combined with immunoprecipitation, Nuc-MS quantified nucleosome co-occupancy of histone H3.3 with variant H2A.Z (sixfold over bulk) and the co-occurrence of oncogenic H3.3K27M with euchromatic marks (for example, a >15-fold enrichment of dimethylated H3K79me2). Nuc-MS is highly concordant with chromatin immunoprecipitation-sequencing (ChIP-seq) and offers a new readout of nucleosome-level biology.
2021-04-20 | GSE149484 | GEO
Project description:Current proteomic approaches disassemble and digest nucleosome particles, blurring readouts of the ‘histone code’. To preserve nucleosome-level information, we developed Nuc-MS, which displays the landscape of histone variants and their post-translational modifications (PTMs) in a single mass spectrum. Combined with immunoprecipitation, Nuc-MS quantified nucleosome co-occupancy of histone H3.3 with variant H2A.Z (sixfold over bulk) and the co-occurrence of oncogenic H3.3K27M with euchromatic marks (for example, a >15-fold enrichment of dimethylated H3K79me2). Nuc-MS is highly concordant with chromatin immunoprecipitation-sequencing (ChIP-seq) and offers a new readout of nucleosome-level biology. Chromatin immunoprecipitation DNA-sequencing (ChIP-seq) for histone variants H3.3, H2AZ as well as the histone modifications H3K79me2 and H4K16ac in HEK293T cells.
2022-11-03 | GSE216732 | GEO
Project description:Current proteomic approaches disassemble and digest nucleosome particles, blurring readouts of the ‘histone code’. To preserve nucleosome-level information, we developed Nuc-MS, which displays the landscape of histone variants and their post-translational modifications (PTMs) in a single mass spectrum. Combined with immunoprecipitation, Nuc-MS quantified nucleosome co-occupancy of histone H3.3 with variant H2A.Z (sixfold over bulk) and the co-occurrence of oncogenic H3.3K27M with euchromatic marks (for example, a >15-fold enrichment of dimethylated H3K79me2). Nuc-MS is highly concordant with chromatin immunoprecipitation-sequencing (ChIP-seq) and offers a new readout of nucleosome-level biology. Chromatin immunoprecipitation DNA-sequencing (ChIP-seq) for RFX1 in hMDMs cells.
2023-11-08 | GSE210668 | GEO
Project description:We developed a system to study the DNA replication-independent turnover nucleosomes containing the histone variant H3.3 in mammalian cells. By measuring the genome-wide incorporation of H3.3 at different time points following epitope-tagged H3.3 expression, we find three categories of H3.3-nucleosome turnover in vivo: rapid turnover, intermediate turnover and, specifically at telomeres, slow turnover. Our data indicate that H3.3-containing nucleosomes at enhancers and promoters undergo a rapid turnover that is associated with active histone modification marks including H3K4me1, H3K4me3, H3K9ac, H3K27ac and the histone variant H2A.Z. The rate of turnover is negatively correlated with H3K27me3 at regulatory regions and with H3K36me3 at gene bodies. Examination of incorporation dynamics of histone variant H3.3
2013-10-23 | E-GEOD-51505 | biostudies-arrayexpress
Project description:We developed a system to study the DNA replication-independent turnover nucleosomes containing the histone variant H3.3 in mammalian cells. By measuring the genome-wide incorporation of H3.3 at different time points following epitope-tagged H3.3 expression, we find three categories of H3.3-nucleosome turnover in vivo: rapid turnover, intermediate turnover and, specifically at telomeres, slow turnover. Our data indicate that H3.3-containing nucleosomes at enhancers and promoters undergo a rapid turnover that is associated with active histone modification marks including H3K4me1, H3K4me3, H3K9ac, H3K27ac and the histone variant H2A.Z. The rate of turnover is negatively correlated with H3K27me3 at regulatory regions and with H3K36me3 at gene bodies.
2013-10-23 | GSE51505 | GEO
Project description:Nucleosomes are the principal packaging units of chromatin and critical for gene regulation and genome stability. In mammals, a subset of nucleosomes fail to be replaced by protamines during spermatogenesis and are retained in mature spermatozoa providing opportunities for paternal epigenetic transmission. In humans, the remaining 10% localize at regulatory elements of genes. To assess evolutionary conservation and to dissect the molecular logic underlying nucleosome retention, we determined the genome wide nucleosome occupancy in mouse spermatozoa that only contain 1% residual histones. In striking contrast to mammalian somatic cells and haploid round spermatids, we observe high enrichment of nucleosomes at CpG-rich sequences throughout the genome, at conserved regulatory sequences as well as at intra- and intergenic regions and repetitive DNA. This preferred occupancy occurs mutually exclusive with DNA methylation both in mouse and human sperm. At unmethylated CpG-rich sequences, residing nucleosomes are largely composed of the H3.3 histone variant, and trimethylated at lysine 4 (H3K4me3). Both canonical H3.1/H3.2 and H3.3 variant histones are present at promoters marked by Polycomb-mediated H3K27me3, which is strongly predictive for gene repression in pre-implantation embryos. Our data indicate important roles of DNA sequence composition, DNA methylation, variant H3.3 and canonical H3.1/H3.2 histones and associated modifications in nucleosome retention versus eviction during the histone-to-protamine remodeling process in elongating spermatids and potentially in epigenetic inheritance by nucleosomes between generations. Identification of histone, histone variant and histone modification states in round spermatids and sperm
2013-06-15 | E-GEOD-42629 | biostudies-arrayexpress
Project description:Nucleosomes are the principal packaging units of chromatin and critical for gene regulation and genome stability. In mammals, a subset of nucleosomes fail to be replaced by protamines during spermatogenesis and are retained in mature spermatozoa providing opportunities for paternal epigenetic transmission. In humans, the remaining 10% localize at regulatory elements of genes. To assess evolutionary conservation and to dissect the molecular logic underlying nucleosome retention, we determined the genome wide nucleosome occupancy in mouse spermatozoa that only contain 1% residual histones. In striking contrast to mammalian somatic cells and haploid round spermatids, we observe high enrichment of nucleosomes at CpG-rich sequences throughout the genome, at conserved regulatory sequences as well as at intra- and intergenic regions and repetitive DNA. This preferred occupancy occurs mutually exclusive with DNA methylation both in mouse and human sperm. At unmethylated CpG-rich sequences, residing nucleosomes are largely composed of the H3.3 histone variant, and trimethylated at lysine 4 (H3K4me3). Both canonical H3.1/H3.2 and H3.3 variant histones are present at promoters marked by Polycomb-mediated H3K27me3, which is strongly predictive for gene repression in pre-implantation embryos. Our data indicate important roles of DNA sequence composition, DNA methylation, variant H3.3 and canonical H3.1/H3.2 histones and associated modifications in nucleosome retention versus eviction during the histone-to-protamine remodeling process in elongating spermatids and potentially in epigenetic inheritance by nucleosomes between generations.
2013-06-15 | GSE42629 | GEO
Project description:Using Tet-inhibited expression of epitope-tagged H3.3 combined with ChIP-Seq we undertook genome-wide measurements of H3.3 dissociation rates across the ESC genome and examined the relationship between H3.3-nucleosome turnover and ESC-specific transcription factors, chromatin modifiers and epigenetic marks. To measure dissociation rates of H3.3, we utilized a TET-repressible ESC line, ES[MC1R(20)], with the expression cassette integrated at the ROSA26 locus. We transfected MC1R ESCs with HA/FLAG-tagged H3.3 controlled by tetracycline response elements. For ‘TET-OFF’ experiments, ESCs were cultured over several passages (weeks) on feeder cells in the absence of DOX and were subsequently passaged onto feeder-free plates prior to the inhibition of HA-H3.3 expression. To repress HA/FLAG-H3.3 expression we treated cells with 2 ?g/ml doxycycline hyclate before crosslinking with formaldehyde at various time points. Measurement of H3.3-HA enrichment over time-course was performed using two replicates of ChIP-seq experiments. As a control, input DNA sequencing was performed for every time point
2015-05-14 | E-GEOD-63641 | biostudies-arrayexpress
Project description:Background: Bivalent chromatin refers to overlapping regions containing activating histone H3 Lys4 trimethylation (H3K4me3) and inactivating H3K27me3 marks. Existence of such bivalent marks on the same nucleosome has only recently been suggested. Previous genome-wide efforts to characterize bivalent chromatin have focused primarily on individual marks to define overlapping zones of bivalency rather than mapping positions of truly bivalent mononucleosomes. Results: Here, we developed an efficacious sequential ChIP technique for examining global positioning of individual bivalent nucleosomes. Using next generation sequencing approaches we show that although individual H3K4me3 and H3K27me3 marks overlap in broad zones, bivalent nucleosomes are focally enriched in the vicinity of the transcription start site (TSS). These seem to occupy the H2A.Z nucleosome positions previously described as salt-labile nucleosomes, and are correlated with low gene expression. Although the enrichment profiles of bivalent nucleosomes show a clear dependency on CpG island content, they demonstrate a stark anti-correlation with methylation status. Conclusions: We show that regional overlap of H3K4me3 and H3K27me3 chromatin tend to be upstream to the TSS, while bivalent nucleosomes with both marks are mainly promoter proximal near the TSS of CpG island-containing genes with poised/low expression. We discuss the implications of the focal enrichment of bivalent nucleosomes around the TSS on the poised chromatin state of promoters in stem cells.
2016-09-13 | GSE86838 | GEO
Project description:Nucleosome composition actively contribute to the chromatin structure and accessibility. To preserve chromatin state during replication, transcription and DNA repair, cells have evolved mechanisms to evict or recycle histones, generating a landscape of differentially aged nucleosomes. To map the stability of nucleosomes, we have adapted the recombination induced tag exchange (RITE) method to Schizosaccharomyces pombe histone H3. The RITE method allows us to study replication-independent protein turnover both through the occurrence of, in our case, new histone H3 and the disappearance or preservation of old histone H3. We contrast the RITE system to nucleosome turnover measured by chromatin incorporation of an epitope-tagged H3 under an inducible promoter. We confirm previous findings that stable nucleosomes are found at heterochromatin, but also at coding regions of actively transcribed genes. Genome-wide comparisons with several chromatin marks showed that high turnover nucleosomes correlate with H2A.Z, acetylated H4 and H3K4me2. The histones with high turnover are primarily found at the nucleosomes on the 5´and/or 3´ edges of the transcribed unit. In addition, in this study we have determined genome-wide maps of all three methylation marks at H4K20. All methylation of H4K20 appeared in low turnover nucleosomes and particularly in euchromatic regions. H4K20me1 marks stable nucleosomes at loci proximal to nucleosome depleted regions (NDR) and H4K20me2/3 were found further inside of transcribed units, especially at coding regions of long genes expressed at low levels. Further, this transcription-dependent accumulation of histone methylations was dependent on the histone chaperone complex FACT (Facilitates Chromatin Transcription), as predicited from its role in recycling nucleosomes during transcription.
2015-03-13 | GSE66865 | GEO