Similar Datasets
Project description:The dynamic incorporation of histone variants influences chromatin structure and many biological processes. In Arabidopsis, the canonical variant H3.1 differs from H3.3 in four residues, one of which (H3.1Phe41) is unique and conserved in plants. However, its evolutionary significance remains unclear. Here, we show that Phe41 first appeared in H3.1 in ferns and became stable during land plant evolution. Unlike H3.1, which is specifically enriched in silent regions, H3.1F41Y variants gain ectopic accumulation at actively transcribed regions. Reciprocal tail and core domain swap experiments between H3.1 and H3.3 show that the H3.1 core, while necessary, is insufficient to restrict H3.1 to silent regions. We conclude that the vascular-plant-specific Phe41 is critical for H3.1 genomic distribution and may act collaboratively with the H3.1 core to regulate deposition patterns. This study reveals that Phe41 may have evolved to provide additional regulation of histone deposition in plants.
| S-EPMC5809374 | biostudies-literature
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: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 variants are critical determinants for chromatin function with diverse regulatory mechanisms. The H3 variants, H3.1 and H3.3, evolved independently in animals and plants. A significant difference between H3.1 and H3.3 is the amino acid variation at position 31, with H3.1 carrying alanine (A), while H3.3 bearing serine (S) in animals or threonine (T) in plants. Both S and T can be phosphorylated, but why plants have selectively adopted T over S remains unclear. Here, we report the specific role of plant H3.3T31 in controlling plant development and stress responses by promoting the deposition of histone H3 lysine 36 trimethylation (H3K36me3) on H3.3. T31 prevents plant-specific H3K27 methyltransferases, ATXR5 and ATXR6, from depositing H3K27 monomethylation (H3K27me1), which inhibits the activity of H3K36 methyltransferase EFS. Substituting H3.3T31 with an S or A residue results in increased ATXR5/6 activity and elevated H3K27me1 levels, leading to a reduction in H3K36me3. Moreover, we show that unlike H3.3 T31S and T31A mutations, cancer-associated G34R and G34W mutations directly disrupt H3K36me3 deposition without affecting H3K27me1. These G34 mutations may also influence H3.3 function through mechanisms beyond the disruption of H3K36me3. Our data suggest a co-evolution of the plant-specific H3.3T31 residue and H3K27 methyltransferases ATXR5/6, which ensures the selective accumulation of H3K27me1 on H3.1 and H3K36me3 on H3.3, thereby enabling proper chromatin function.
2026-01-29 | GSE289942 | GEO
Project description:Nucleosomes package eukaryotic DNA and are composed of four different histone proteins, H3, H4, H2A and H2B. Histone H3 has two main variants, H3.1 and H3.3, which show different genomic localization patterns in animals. We profiled H3.1 and H3.3 variants in the genome of the plant Arabidopsis thaliana and show that the localization of these variants shows broad similarity in plants and animals, in addition to some unique features. H3.1 was enriched in silent areas of the genome including regions containing the repressive chromatin modifications H3 lysine 27 methylation, H3 lysine 9 methylation, and DNA methylation. In contrast, H3.3 was enriched in actively transcribed genes, especially peaking at the 3’ end of genes, and correlated with histone modifications associated with gene activation such as histone H3 lysine 4 methylation, and H2B ubiquitylation, as well as by RNA Pol II occupancy. Surprisingly, both H3.1 and H3.3 were enriched on defined origins of replication, as was overall nucleosome density, suggesting a novel characteristic of plant origins. Our results are broadly consistent with the hypothesis that H3.1 acts as the canonical histone that is incorporated during DNA replication, whereas H3.3 acts as the replacement histone that can be incorporated outside of S-phase during chromatin disrupting processes like transcription. ChIP-seq - 4 samples: 2 experiment and 2 controls RNA-seq - 1 sample
2012-03-05 | E-GEOD-34840 | biostudies-arrayexpress
Project description:Histone variants are critical determinants for chromatin function with diverse regulatory mechanisms. The H3 variants, H3.1 and H3.3, evolved independently in animals and plants. A significant difference between H3.1 and H3.3 is the amino acid variation at position 31, with H3.1 carrying alanine (A), while H3.3 bearing serine (S) in animals or threonine (T) in plants. Both S and T can be phosphorylated, but why plants have selectively adopted T over S remains unclear. Here, we report the specific role of plant H3.3T31 in controlling plant development and stress responses by promoting the deposition of histone H3 lysine 36 trimethylation (H3K36me3) on H3.3. T31 prevents plant-specific H3K27 methyltransferases, ATXR5 and ATXR6, from depositing H3K27 monomethylation (H3K27me1), which inhibits the activity of H3K36 methyltransferase EFS. Substituting H3.3T31 with an S or A residue results in increased ATXR5/6 activity and elevated H3K27me1 levels, leading to a reduction in H3K36me3. Moreover, we show that unlike H3.3 T31S and T31A mutations, cancer-associated G34R and G34W mutations directly disrupt H3K36me3 deposition without affecting H3K27me1. These G34 mutations may also influence H3.3 function through mechanisms beyond the disruption of H3K36me3. Our data suggest a co-evolution of the plant-specific H3.3T31 residue and H3K27 methyltransferases ATXR5/6, which ensures the selective accumulation of H3K27me1 on H3.1 and H3K36me3 on H3.3, thereby enabling proper chromatin function.
2026-01-29 | GSE290084 | GEO
Project description:Histone variants are critical determinants for chromatin function with diverse regulatory mechanisms. The H3 variants, H3.1 and H3.3, evolved independently in animals and plants. A significant difference between H3.1 and H3.3 is the amino acid variation at position 31, with H3.1 carrying alanine (A), while H3.3 bearing serine (S) in animals or threonine (T) in plants. Both S and T can be phosphorylated, but why plants have selectively adopted T over S remains unclear. Here, we report the specific role of plant H3.3T31 in controlling plant development and stress responses by promoting the deposition of histone H3 lysine 36 trimethylation (H3K36me3) on H3.3. T31 prevents plant-specific H3K27 methyltransferases, ATXR5 and ATXR6, from depositing H3K27 monomethylation (H3K27me1), which inhibits the activity of H3K36 methyltransferase EFS. Substituting H3.3T31 with an S or A residue results in increased ATXR5/6 activity and elevated H3K27me1 levels, leading to a reduction in H3K36me3. Moreover, we show that unlike H3.3 T31S and T31A mutations, cancer-associated G34R and G34W mutations directly disrupt H3K36me3 deposition without affecting H3K27me1. These G34 mutations may also influence H3.3 function through mechanisms beyond the disruption of H3K36me3. Our data suggest a co-evolution of the plant-specific H3.3T31 residue and H3K27 methyltransferases ATXR5/6, which ensures the selective accumulation of H3K27me1 on H3.1 and H3K36me3 on H3.3, thereby enabling proper chromatin function.
2026-01-29 | GSE290083 | GEO
Project description:Histone variants are critical determinants for chromatin function with diverse regulatory mechanisms. The H3 variants, H3.1 and H3.3, evolved independently in animals and plants. A significant difference between H3.1 and H3.3 is the amino acid variation at position 31, with H3.1 carrying alanine (A), while H3.3 bearing serine (S) in animals or threonine (T) in plants. Both S and T can be phosphorylated, but why plants have selectively adopted T over S remains unclear. Here, we report the specific role of plant H3.3T31 in controlling plant development and stress responses by promoting the deposition of histone H3 lysine 36 trimethylation (H3K36me3) on H3.3. T31 prevents plant-specific H3K27 methyltransferases, ATXR5 and ATXR6, from depositing H3K27 monomethylation (H3K27me1), which inhibits the activity of H3K36 methyltransferase EFS. Substituting H3.3T31 with an S or A residue results in increased ATXR5/6 activity and elevated H3K27me1 levels, leading to a reduction in H3K36me3. Moreover, we show that unlike H3.3 T31S and T31A mutations, cancer-associated G34R and G34W mutations directly disrupt H3K36me3 deposition without affecting H3K27me1. These G34 mutations may also influence H3.3 function through mechanisms beyond the disruption of H3K36me3. Our data suggest a co-evolution of the plant-specific H3.3T31 residue and H3K27 methyltransferases ATXR5/6, which ensures the selective accumulation of H3K27me1 on H3.1 and H3K36me3 on H3.3, thereby enabling proper chromatin function.
2026-01-29 | GSE289944 | GEO
Project description:Histone variants are critical determinants for chromatin function with diverse regulatory mechanisms. The H3 variants, H3.1 and H3.3, evolved independently in animals and plants. A significant difference between H3.1 and H3.3 is the amino acid variation at position 31, with H3.1 carrying alanine (A), while H3.3 bearing serine (S) in animals or threonine (T) in plants. Both S and T can be phosphorylated, but why plants have selectively adopted T over S remains unclear. Here, we report the specific role of plant H3.3T31 in controlling plant development and stress responses by promoting the deposition of histone H3 lysine 36 trimethylation (H3K36me3) on H3.3. T31 prevents plant-specific H3K27 methyltransferases, ATXR5 and ATXR6, from depositing H3K27 monomethylation (H3K27me1), which inhibits the activity of H3K36 methyltransferase EFS. Substituting H3.3T31 with an S or A residue results in increased ATXR5/6 activity and elevated H3K27me1 levels, leading to a reduction in H3K36me3. Moreover, we show that unlike H3.3 T31S and T31A mutations, cancer-associated G34R and G34W mutations directly disrupt H3K36me3 deposition without affecting H3K27me1. These G34 mutations may also influence H3.3 function through mechanisms beyond the disruption of H3K36me3. Our data suggest a co-evolution of the plant-specific H3.3T31 residue and H3K27 methyltransferases ATXR5/6, which ensures the selective accumulation of H3K27me1 on H3.1 and H3K36me3 on H3.3, thereby enabling proper chromatin function.
2026-01-29 | GSE290160 | GEO
Project description:Histone variants are critical determinants for chromatin function with diverse regulatory mechanisms. The H3 variants, H3.1 and H3.3, evolved independently in animals and plants. A significant difference between H3.1 and H3.3 is the amino acid variation at position 31, with H3.1 carrying alanine (A), while H3.3 bearing serine (S) in animals or threonine (T) in plants. Both S and T can be phosphorylated, but why plants have selectively adopted T over S remains unclear. Here, we report the specific role of plant H3.3T31 in controlling plant development and stress responses by promoting the deposition of histone H3 lysine 36 trimethylation (H3K36me3) on H3.3. T31 prevents plant-specific H3K27 methyltransferases, ATXR5 and ATXR6, from depositing H3K27 monomethylation (H3K27me1), which inhibits the activity of H3K36 methyltransferase EFS. Substituting H3.3T31 with an S or A residue results in increased ATXR5/6 activity and elevated H3K27me1 levels, leading to a reduction in H3K36me3. Moreover, we show that unlike H3.3 T31S and T31A mutations, cancer-associated G34R and G34W mutations directly disrupt H3K36me3 deposition without affecting H3K27me1. These G34 mutations may also influence H3.3 function through mechanisms beyond the disruption of H3K36me3. Our data suggest a co-evolution of the plant-specific H3.3T31 residue and H3K27 methyltransferases ATXR5/6, which ensures the selective accumulation of H3K27me1 on H3.1 and H3K36me3 on H3.3, thereby enabling proper chromatin function.
2026-01-29 | GSE290158 | GEO