Project description:This SuperSeries is composed of the following subset Series: GSE36626: Dynamic Deposition of the Histone H3.3 Variant Accompanies Developmental Remodeling of Arabidopsis Transcriptome (mRNA-Seq) GSE36629: Dynamic Deposition of the Histone H3.3 Variant Accompanies Developmental Remodeling of Arabidopsis Transcriptome (ChIP-Seq) Refer to individual Series
Project description:In animals, replication coupled histone H3.1 can be distinguished from replication independent histone H3.3. H3.3 variants are enriched at active genes and their promoters. Furthermore, H3.3 is specifically incorporated upon gene activation. Histone H3 variants evolved independently in plants and animals and it is unclear whether different replication independent H3.3 variants developed similar properties in both phyla. We studied Arabidopsis H3 variants in order to find core properties of this class of histones. Here we present genome-wide maps of H3.3 and H3.1 enrichment and the dynamic changes of their profiles upon cell division arrest. We find H3.3 enrichment to positively correlate with gene expression and to be biased towards the transcription termination site. While heterochromatic regions are mostly depleted of H3.3, H3.1 shows a more even distribution along the genome. We report that in planta, dynamic changes in H3.3 profiles are associated with the extensive remodeling of the transcriptome that occurs during cell differentiation. We propose that H3.3 dynamics are linked to transcription and are involved in resetting covalent histone marks at a genomic scale during plant development. Similarities between plant and animal H3.3 deposition profiles indicate that H3 variants likely result from functionally convergent evolution. Analysis of 2 different histone H3 variants and transcriptome in 2 conditions.
Project description:In animals, replication coupled histone H3.1 can be distinguished from replication independent histone H3.3. H3.3 variants are enriched at active genes and their promoters. Furthermore, H3.3 is specifically incorporated upon gene activation. Histone H3 variants evolved independently in plants and animals and it is unclear whether different replication independent H3.3 variants developed similar properties in both phyla. We studied Arabidopsis H3 variants in order to find core properties of this class of histones. Here we present genome-wide maps of H3.3 and H3.1 enrichment and the dynamic changes of their profiles upon cell division arrest. We find H3.3 enrichment to positively correlate with gene expression and to be biased towards the transcription termination site. While heterochromatic regions are mostly depleted of H3.3, H3.1 shows a more even distribution along the genome. We report that in planta, dynamic changes in H3.3 profiles are associated with the extensive remodeling of the transcriptome that occurs during cell differentiation. We propose that H3.3 dynamics are linked to transcription and are involved in resetting covalent histone marks at a genomic scale during plant development. Similarities between plant and animal H3.3 deposition profiles indicate that H3 variants likely result from functionally convergent evolution. Analysis of 2 different histone H3 variants and transcriptome in 2 conditions.
Project description:Polycomb repressive complex 2 (PRC2) regulates gene expression during lineage specification through trimethylation of lysine 27 on histone H3 (H3K27me3). In Drosophila, polycomb binding sites are dynamic chromatin regions coupled to incorporation of the histone variant H3.3. Here we show in mouse embryonic stem cells (ESCs) that H3.3 is required for proper establishment of H3K27me3 at the promoters of developmentally regulated genes. These promoters show reduced dynamics as determined by deposition of de novo synthesized histones, associated with reduced PRC2 occupancy. H3.3-depleted ESCs show upregulation of extraembryonic trophectoderm, as well as misregulation of other developmental genes upon differentiation. Our data demonstrate the importance of H3.3 incorporation in ESCs and suggest that changes in chromatin dynamics in its absence lead to misregulation of gene expression during differentiation. Moreover, our findings lend support to the emerging notion that H3.3 has multiple functions in distinct genomic locations that are not always correlated with an “active” chromatin state. RNA-seq analysis of three embryonic stem cell lines (control, H3.3 KD1, and H3.3 KD2)
Project description:Polycomb repressive complex 2 (PRC2) regulates gene expression during lineage specification through trimethylation of lysine 27 on histone H3 (H3K27me3). In Drosophila, polycomb binding sites are dynamic chromatin regions coupled to incorporation of the histone variant H3.3. Here we show in mouse embryonic stem cells (ESCs) that H3.3 is required for proper establishment of H3K27me3 at the promoters of developmentally regulated genes. These promoters show reduced dynamics as determined by deposition of de novo synthesized histones, associated with reduced PRC2 occupancy. H3.3-depleted ESCs show upregulation of extraembryonic trophectoderm, as well as misregulation of other developmental genes upon differentiation. Our data demonstrate the importance of H3.3 incorporation in ESCs and suggest that changes in chromatin dynamics in its absence lead to misregulation of gene expression during differentiation. Moreover, our findings lend support to the emerging notion that H3.3 has multiple functions in distinct genomic locations that are not always correlated with an “active” chromatin state. CATCH-IT analysis of five embryonic stem cell lines (control, H3.3 KD1, and H3.3 KD2; wild type and Hira-/-)
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.
Project description:Polycomb repressive complex 2 (PRC2) regulates gene expression during lineage specification through trimethylation of lysine 27 on histone H3 (H3K27me3). In Drosophila, polycomb binding sites are dynamic chromatin regions coupled to incorporation of the histone variant H3.3. Here we show in mouse embryonic stem cells (ESCs) that H3.3 is required for proper establishment of H3K27me3 at the promoters of developmentally regulated genes. These promoters show reduced dynamics as determined by deposition of de novo synthesized histones, associated with reduced PRC2 occupancy. H3.3-depleted ESCs show upregulation of extraembryonic trophectoderm, as well as misregulation of other developmental genes upon differentiation. Our data demonstrate the importance of H3.3 incorporation in ESCs and suggest that changes in chromatin dynamics in its absence lead to misregulation of gene expression during differentiation. Moreover, our findings lend support to the emerging notion that H3.3 has multiple functions in distinct genomic locations that are not always correlated with an “active” chromatin state. Native ChIP analysis of three histone post-translational modifications (H3K4me3, H3K27me3, H3K27ac) in two mouse embryonic stem cell (ESC) lines (control and H3.3-depleted). Inputs sequenced as control. Native ChIP analysis of H3.3B-HA in control and Suz12-/- ESCs. Crosslinking ChIP analysis of histone H3 using a general H3 antibody in two ESC lines (control and H3.3-depleted). Crosslinking ChIP analysis Hira, UTX, and Jmjd3 in wild type and H3.3 KO ESCs.
Project description:In animals, replication coupled histone H3.1 can be distinguished from replication independent histone H3.3. H3.3 variants are enriched at active genes and their promoters. Furthermore, H3.3 is specifically incorporated upon gene activation. Histone H3 variants evolved independently in plants and animals and it is unclear whether different replication independent H3.3 variants developed similar properties in both phyla. We studied Arabidopsis H3 variants in order to find core properties of this class of histones. Here we present genome-wide maps of H3.3 and H3.1 enrichment and the dynamic changes of their profiles upon cell division arrest. We find H3.3 enrichment to positively correlate with gene expression and to be biased towards the transcription termination site. While heterochromatic regions are mostly depleted of H3.3, H3.1 shows a more even distribution along the genome. We report that in planta, dynamic changes in H3.3 profiles are associated with the extensive remodeling of the transcriptome that occurs during cell differentiation. We propose that H3.3 dynamics are linked to transcription and are involved in resetting covalent histone marks at a genomic scale during plant development. Similarities between plant and animal H3.3 deposition profiles indicate that H3 variants likely result from functionally convergent evolution.