Histone H3 availability is more important for development than H3.2 versus H3.3 subtype identity
Ontology highlight
ABSTRACT:
ORGANISM(S): Drosophila melanogaster
PROVIDER: GSE317810 | GEO | 2026/06/08
REPOSITORIES: GEO
Similar Datasets
Project description:The distinct contributions of replication-dependent (RD) and replication-independent (RI) histones to development and genome function remain unclear. We investigate how the RI expression and distinct protein identities of the histone H3.2 and H3.3 subtypes influence Drosophila development and gene regulation. Replacing RI H3.3 genes with RD H3.2 revealed that RI H3.3 is essential for fertility, adult locomotor behavior, and normal lifespan. However, development to adulthood does not depend on which RI H3 subtype is expressed. RI H3 is dispensable for establishing or maintaining global chromatin accessibility or gene expression in the adult brain. H3.2 expression becomes essential in post-mitotic cells lacking RI H3.3, and the HIRA histone chaperone complex in critical for preserving genome function when RI H3.3 is deleted. We conclude that an available pool of H3 is more critical than the specific identity of H3 in the pool.
2026-06-08 | GSE317848 | GEO
Project description:The incorporation of histone H3 variants has been implicated in the epigenetic memory of cellular state. Using genome editing with zinc finger nucleases to tag endogenous H3.3, we report genome-wide profiles of H3 variants in mammalian embryonic stem (ES) cells and neuronal precursor cells. Genome-wide patterns of H3.3 are dependent on amino acid sequence, and change with cellular differentiation at developmentally regulated loci. The H3.3 chaperone Hira is required for H3.3 enrichment at active and repressed genes. Strikingly, Hira is not essential for localization of H3.3 at telomeres and many transcription factor binding sites. Immunoaffinity purification and mass spectrometry reveal that the proteins Atrx and Daxx associate with H3.3 in a Hira-independent manner. Atrx is required for Hira-independent localization of H3.3 at telomeres, and for the repression of telomeric RNA. Our data demonstrate that multiple and distinct factors are responsible for H3.3 localization at specific genomic locations in mammalian cells. Crosslinking ChIP-seq: Examination of 1 histone variant (H3.3), 2 histone modifications, and Serine-5 phosphorylated RNA polymerase in 2 different cell types (H3.3-HA ES samples 1-4, and H3.3-HA NPC samples 7-10). Examination of 1 histone variant (H3.2), and one histone modification (H3K36me3) in 2 different cell types (H3.2-HA ES samples 5-6, and H3.2-HA NPC samples 11-12). Examination of 1 histone variant (H3.3), input control, and one histone modification (H3K36me3) in one cell type (H3.3-HA hybrid ES, samples 13-15). Examination of 1 histone variant (H3.1S31), input control, and one histone modification (H3K36me3) in one cell type (H3.1S31-HA hybrid ES, samples 16-18). Native ChIP-seq: Examination of 1 histone variant (H3.3), input control, and one histone modification (H3K4me3) in one cell type (H3.3-HA ES, samples 19-21). Examination of 1 histone variant (H3.2), input control, and two histone modifications (H3K4me3 and H3K27me3) in one cell type (H3.2-HA ES, samples 22-25). Examination of 1 histone variant (H3.3), input control, and two histone modifications (H3K4me1 and H3K36me3) in one cell type (H3.3-EYFP ES, samples 26-29). Examination of 1 histone variant (H3.3), input control, and two histone modifications (H3K4me1 and H3K36me3) in one cell type (Hira -/- H3.3-EYFP ES, samples 30-33). Examination of 1 histone variant (H3.3) and input control in one cell type (Atrxflox H3.3-EYFP ES, samples 34-37). Examination of HA antibody background in one cell type (wild-type ES, sample 38).
2010-03-04 | E-GEOD-16893 | biostudies-arrayexpress
Project description:Establishment of a proper chromatin landscape is central to genome function. Here, we explain H3 variant distribution by specific targeting and dynamics of deposition involving the CAF-1 and HIRA histone chaperones. Impairing replicative H3.1 incorporation via CAF-1 enables an alternative H3.3 deposition at replication sites via HIRA. Conversely, the H3.3 incorporation throughout the cell cycle via HIRA cannot be replaced by H3.1. ChIP-seq analyses reveal correlation between HIRA-dependent H3.3 accumulation and RNA pol II at transcription sites and specific regulatory elements, further supported by their biochemical association. Remarkably, the HIRA complex shows unique DNA binding properties and depleting HIRA increases DNA sensitivity to nucleases. We propose that protective gap-filling of naked DNA by HIRA leads to a broad distribution of H3.3, and HIRA association with Pol II ensures local H3.3 enrichment at specific sites. Examination of genome-wide localization of two histone H3 variants.
2011-12-16 | E-GEOD-31794 | biostudies-arrayexpress
Project description:Replication-independent deposition of histone variant H3.3 into chromatin is essential for many biological processes, including development, oogenesis and nuclear reprogramming. Unlike replication-dependent H3.1/2 isoforms, H3.3 is expressed throughout the cell cycle and becomes enriched in postmitotic cells with age. However, lifelong dynamics of H3 variant replacement and the impact of this process on chromatin organization remain largely undefined. To address this, we investigated genome-wide changes in histone H3 variants composition and H3 modification abundances throughout the lifespan in mice using quantitative mass spectrometry (MS) – based middle-down proteomics strategy. Using middle-down MS we demonstrate that H3.3 accumulates in the chromatin of various somatic mouse tissues throughout life, resulting in near complete replacement of H3.1/2 isoforms by the late adulthood. Accumulation of H3.3 is associated with profound changes in the global level of H3 methylation. H3.3-containing chromatin exhibits distinct stable levels of H3R17me2 and H3K36me2, different from those on H3.1/H3.2-containing chromatin, indicating a direct link between H3 variant exchange and histone methylation dynamics with age. In summary, our study provides the first time comprehensive characterization of dynamic changes in the H3 modification landscape during mouse lifespan and links these changes to the age-dependent accumulation of histone variant H3.3.
2017-07-28 | PXD005300 | Pride
Project description:Establishment of a proper chromatin landscape is central to genome function. Here, we explain H3 variant distribution by specific targeting and dynamics of deposition involving the CAF-1 and HIRA histone chaperones. Impairing replicative H3.1 incorporation via CAF-1 enables an alternative H3.3 deposition at replication sites via HIRA. Conversely, the H3.3 incorporation throughout the cell cycle via HIRA cannot be replaced by H3.1. ChIP-seq analyses reveal correlation between HIRA-dependent H3.3 accumulation and RNA pol II at transcription sites and specific regulatory elements, further supported by their biochemical association. Remarkably, the HIRA complex shows unique DNA binding properties and depleting HIRA increases DNA sensitivity to nucleases. We propose that protective gap-filling of naked DNA by HIRA leads to a broad distribution of H3.3, and HIRA association with Pol II ensures local H3.3 enrichment at specific sites.
2011-12-16 | GSE31794 | GEO
Project description:Histone variants contribute to the complexity of the chromatin landscape and play an integral role in defining DNA domains and regulating gene expression. The histone H3 variant H3.3 is incorporated into genic elements independent of DNA replication by its chaperone HIRA. Here we demonstrate that Hira is required for the self-renewal of adult hematopoietic stem cells (HSCs) and to restrain erythroid differentiation. Deletion of Hira led to rapid depletion of HSCs while differentiated hematopoietic cells remained largely unaffected. Depletion of HSCs after Hira deletion was accompanied by increased expression of bivalent and erythroid genes, which were exacerbated upon cell division and paralleled increased erythroid differentiation. Assessing H3.3 occupancy identified a subset of polycomb-repressed chromatin in HSCs that depend on HIRA to maintain the inaccessible, H3.3-occupied state for gene repression. HIRA-dependent H3.3 incorporation thus defines distinct repressive chromatin that represses erythroid differentiation of HSCs.
2021-07-08 | GSE163198 | GEO
Project description:Histone variants contribute to the complexity of the chromatin landscape and play an integral role in defining DNA domains and regulating gene expression. The histone H3 variant H3.3 is incorporated into genic elements independent of DNA replication by its chaperone HIRA. Here we demonstrate that Hira is required for the self-renewal of adult hematopoietic stem cells (HSCs) and to restrain erythroid differentiation. Deletion of Hira led to rapid depletion of HSCs while differentiated hematopoietic cells remained largely unaffected. Depletion of HSCs after Hira deletion was accompanied by increased expression of bivalent and erythroid genes, which were exacerbated upon cell division and paralleled increased erythroid differentiation. Assessing H3.3 occupancy identified a subset of polycomb-repressed chromatin in HSCs that depend on HIRA to maintain the inaccessible, H3.3-occupied state for gene repression. HIRA-dependent H3.3 incorporation thus defines distinct repressive chromatin that represses erythroid differentiation of HSCs.
2021-07-08 | GSE163051 | GEO
Project description:Histone variants contribute to the complexity of the chromatin landscape and play an integral role in defining DNA domains and regulating gene expression. The histone H3 variant H3.3 is incorporated into genic elements independent of DNA replication by its chaperone HIRA. Here we demonstrate that Hira is required for the self-renewal of adult hematopoietic stem cells (HSCs) and to restrain erythroid differentiation. Deletion of Hira led to rapid depletion of HSCs while differentiated hematopoietic cells remained largely unaffected. Depletion of HSCs after Hira deletion was accompanied by increased expression of bivalent and erythroid genes, which were exacerbated upon cell division and paralleled increased erythroid differentiation. Assessing H3.3 occupancy identified a subset of polycomb-repressed chromatin in HSCs that depend on HIRA to maintain the inaccessible, H3.3-occupied state for gene repression. HIRA-dependent H3.3 incorporation thus defines distinct repressive chromatin that represses erythroid differentiation of HSCs.
2021-07-08 | GSE163050 | GEO
Project description:We developed a new sequencing assay to track the de novo deposition of the histone H3 variants H3.1 and H3.3 during S phase. We use cells stably expressing H3.1-SNAP or H3.3-SNAP, and synchronize them in G1/S by double-thymidine block. The SNAP-tag enables to discriminate newly synthesized histones from preexisting ones, via a quench-chase-capture strategy. We applied this strategy to isolate new H3.1 and H3.3 after releasing cells into S phase, and probed their distribution by MNase digestion and sequencing. We could thus characterize H3.1 and H3.3 dynamics from early to mid S phase at genome-wide resolution. We further applied our method to investigate the consequences of perturbations upon deletion of the H3.3 chaperone HIRA. We used HIRA knockout and control cells, and compared H3.1 and H3.3 distribution to early replication patterns by EdU labeling and sequencing of nascent DNA.
2022-03-31 | E-MTAB-10619 | biostudies-arrayexpress
Project description:Histone chaperones and chromatin remodelers control nucleosome dynamics, essential for transcription, replication, and DNA repair. The histone chaperone Anti-Silencing Factor 1 (ASF1) plays a central role in facilitating CAF-1-mediated replication-dependent H3.1 deposition and HIRA-mediated replication-independent H3.3 deposition in yeast and metazoans. Whether ASF1 function is evolutionarily conserved in plants is unknown. Here, we show that Arabidopsis ASF1 proteins display an exclusive preference for the H3.3-depositing HIRA complex. Simultaneous mutation of both Arabidopsis ASF1 genes caused a decrease in chromatin density and ectopic H3.1 occupancy at loci typically enriched with H3.3. Genetic, transcriptomic, and proteomic data indicate that ASF1 proteins strongly prefer the HIRA complex over CAF-1. asf1 mutants also displayed an increase in spurious Pol II transcriptional initiation, and showed defects in the maintenance of gene body CG DNA methylation and in the distribution of histone modifications. Furthermore, ectopic targeting of ASF1 caused excessive histone deposition, less accessible chromatin, and gene silencing. These findings reveal the importance of ASF1-mediated H3.3-H4 deposition via the HIRA pathway for proper epigenetic regulation of the genome.
2022-10-31 | PXD035578 | Pride