Project description:Osmotic stress induces phosphorylation of histone H3 at threonine 3 in pericentromeric regions of Arabidopsis thaliana [expression]
2015-12-02 | E-GEOD-68439 | ExpressionAtlas
Project description:Osmotic stress induces phosphorylation of histone H3 at threonine 3 in pericentromeric regions of Arabidopsis thaliana
Project description:Histone phosphorylation plays key roles in stress-induced transcriptional reprogramming in metazoans but its function(s) in land plants has remained relatively unexplored. Here we report that an Arabidopsis mutant defective in At3g03940 and At5g18190, encoding closely related Ser/Thr protein kinases, shows pleiotropic phenotypes including dwarfism and hypersensitivity to osmotic/salt stress. The double mutant has reduced global levels of phosphorylated histone H3 threonine 3 (H3T3ph), which are not enhanced, unlike the response in the wild type, by drought-like treatments. Genome-wide analyses revealed increased H3T3ph, slight enhancement in trimethylated histone H3 lysine 4 (H3K4me3), and a modest decrease in histone H3 occupancy in pericentromeric/knob regions of wild type plants under osmotic stress. However, despite these changes in heterochromatin, transposons and repeats remained largely transcriptionally repressed. In contrast, this reorganization of heterochromatin was mostly absent in the double mutant, which even under normal conditions exhibited lower H3T3ph levels in pericentromeric regions, and a few transposons and repeat sequences showed modest transcriptional activation. Interestingly, within actively transcribed protein-coding genes, H3T3ph density was minimal in 5’ genic regions, coincidental with a peak of H3K4me3 accumulation. This pattern was not affected in the double mutant, implying the existence of additional H3T3 protein kinases in Arabidopsis. Our results suggest that At3g03940 and At5g18190 are involved in the phosphorylation of H3T3 in pericentromeric/knob regions and that this repressive epigenetic mark may be important for maintaining proper heterochromatic organization and, possibly, chromosome function(s). Columbia-0 and double mutant at3g03940/at518190 knockdown plants were grown in 12 hr light for 3 weeks in pots in well-watered state. RNA was isolated from rosettes in triplicate for analysis on microarray.
Project description:Histone phosphorylation plays key roles in stress-induced transcriptional reprogramming in metazoans but its function(s) in land plants has remained relatively unexplored. Here we report that an Arabidopsis mutant defective in At3g03940 and At5g18190, encoding closely related Ser/Thr protein kinases, shows pleiotropic phenotypes including dwarfism and hypersensitivity to osmotic/salt stress. The double mutant has reduced global levels of phosphorylated histone H3 threonine 3 (H3T3ph), which are not enhanced, unlike the response in the wild type, by drought-like treatments. Genome-wide analyses revealed increased H3T3ph, slight enhancement in trimethylated histone H3 lysine 4 (H3K4me3), and a modest decrease in histone H3 occupancy in pericentromeric/knob regions of wild type plants under osmotic stress. However, despite these changes in heterochromatin, transposons and repeats remained largely transcriptionally repressed. In contrast, this reorganization of heterochromatin was mostly absent in the double mutant, which even under normal conditions exhibited lower H3T3ph levels in pericentromeric regions, and a few transposons and repeat sequences showed modest transcriptional activation. Interestingly, within actively transcribed protein-coding genes, H3T3ph density was minimal in 5’ genic regions, coincidental with a peak of H3K4me3 accumulation. This pattern was not affected in the double mutant, implying the existence of additional H3T3 protein kinases in Arabidopsis. Our results suggest that At3g03940 and At5g18190 are involved in the phosphorylation of H3T3 in pericentromeric/knob regions and that this repressive epigenetic mark may be important for maintaining proper heterochromatic organization and, possibly, chromosome function(s).
Project description:Histone phosphorylation plays key roles in stress-induced transcriptional reprogramming in metazoans but its function(s) in land plants has remained relatively unexplored. Here we report that an Arabidopsis mutant defective in At3g03940 and At5g18190, encoding closely related Ser/Thr protein kinases, shows pleiotropic phenotypes including dwarfism and hypersensitivity to osmotic/salt stress. The double mutant has reduced global levels of phosphorylated histone H3 threonine 3 (H3T3ph), which are not enhanced, unlike the response in the wild type, by drought-like treatments. Genome-wide analyses revealed increased H3T3ph, slight enhancement in trimethylated histone H3 lysine 4 (H3K4me3), and a modest decrease in histone H3 occupancy in pericentromeric/knob regions of wild type plants under osmotic stress. However, despite these changes in heterochromatin, transposons and repeats remained largely transcriptionally repressed. In contrast, this reorganization of heterochromatin was mostly absent in the double mutant, which even under normal conditions exhibited lower H3T3ph levels in pericentromeric regions, and a few transposons and repeat sequences showed modest transcriptional activation. Interestingly, within actively transcribed protein-coding genes, H3T3ph density was minimal in 5’ genic regions, coincidental with a peak of H3K4me3 accumulation. This pattern was not affected in the double mutant, implying the existence of additional H3T3 protein kinases in Arabidopsis. Our results suggest that At3g03940 and At5g18190 are involved in the phosphorylation of H3T3 in pericentromeric/knob regions and that this repressive epigenetic mark may be important for maintaining proper heterochromatic organization and, possibly, chromosome function(s).
Project description:Histone phosphorylation plays key roles in stress-induced transcriptional reprogramming in metazoans but its function(s) in land plants has remained relatively unexplored. Here we report that an Arabidopsis mutant defective in At3g03940 and At5g18190, encoding closely related Ser/Thr protein kinases, shows pleiotropic phenotypes including dwarfism and hypersensitivity to osmotic/salt stress. The double mutant has reduced global levels of phosphorylated histone H3 threonine 3 (H3T3ph), which are not enhanced, unlike the response in the wild type, by drought-like treatments. Genome-wide analyses revealed increased H3T3ph, slight enhancement in trimethylated histone H3 lysine 4 (H3K4me3), and a modest decrease in histone H3 occupancy in pericentromeric/knob regions of wild type plants under osmotic stress. However, despite these changes in heterochromatin, transposons and repeats remained largely transcriptionally repressed. In contrast, this reorganization of heterochromatin was mostly absent in the double mutant, which even under normal conditions exhibited lower H3T3ph levels in pericentromeric regions, and a few transposons and repeat sequences showed modest transcriptional activation. Interestingly, within actively transcribed protein-coding genes, H3T3ph density was minimal in 5’ genic regions, coincidental with a peak of H3K4me3 accumulation. This pattern was not affected in the double mutant, implying the existence of additional H3T3 protein kinases in Arabidopsis. Our results suggest that At3g03940 and At5g18190 are involved in the phosphorylation of H3T3 in pericentromeric/knob regions and that this repressive epigenetic mark may be important for maintaining proper heterochromatic organization and, possibly, chromosome function(s). Columbia-0 and double mutant at3g03940/at518190 knockdown plants were grown in 12 hr light for 3 weeks in pots with soil covered with miracloth to prevent soil contamination of leaf tissues. Control was kept in normal watered state, for other samples (peg) drought stress was induced by treatment with 30% Polyethylene glycol (PEG 6,000) for 5 hours. Pulldowns on H3, H3K4, and H3T3 were performed on all samples with 3-4 replicates.
Project description:Upon androgen stimulation, PKN1-mediated histone H3 threonine 11 phosphorylation (H3T11P) promotes AR target genes activation. However, the underlying mechanism is not completely understood. Here, we show that WDR5, a subunit of the SET1/MLL complex, interacts with H3T11P and this interaction facilitates the recruitment of the SET1/MLL complex and subsequent H3K4 trimethylation (H3K4me3). Using ChIP-seq, we find that androgen stimulation results in a six-fold increase in the number of H3T11P-marked regions and induces WDR5 colocalization to one third of H3T11P-enriched promoters, thus establishing a genome-wide relationship between H3T11P and recruitment of WDR5. Accordingly, PKN1 knock-down or chemical inhibition severely blocks WDR5 association and H3K4me3 on AR target genes. Finally, WDR5 is critical in prostate cancer cell proliferation, and is hyperexpressed in human prostate cancers. Together, these results identify WDR5 as a critical epigenomic integrator of histone phosphorylation and methylation and a major driver of androgen-dependent prostate cancer cell proliferation. Identification of Histone 3 threonine 11 phosphorylation (H3T11P) marks and WDR5 binding sites in LNCaP cells treated with R1881 ligand (androgen) or solvent control.
Project description:Purpose: In this study, we show that DNA damage-activated AKT phosphorylates threonine 45 of core histone H3 (H3-T45) Result: By genome-wide chromatin immunoprecipitation sequencing (ChIP-seq) analysis, H3-T45 phosphorylation was distributed throughout DNA damage-responsive gene loci, particularly immediately after the transcription termination site Conclusion: AKT-mediated phosphorylation of H3-T45 regulates the processing of the 3′ end of DNA damage-activated genes to facilitate transcriptional termination MCF10A cells were ChIPed with anti-phosphorylated H3-T45, anti-phosphorylated RNA Pol II-S2 and S5, and anti-H3-K36me3.
Project description:Histone 3 lysine 4 and histone 3 lysine 9 methylation in wild type and ddm1 Arabidopsis thaliana seedlings. The purpose of the chromatin immunoprecipitation/microarray (ChIP/chip) experiment is to determine which regions of a genome are enriched for a particular histone modification in a single Arabidopsis thanliana genotype. Chromatin immunoprecipitation with antibodies raised against dimethyl histone-H3 lysine-9 (H3mK9) or dimethyl histone-H3 lysine-4 (H3mK4) is performed on a selected genotype. This purified DNA from each immunoprecipiation (mH3K9, mH3K4, no antibody control) is used for random amplification to increase the quantity of DNA for microarray hybridization. The amplified DNA from each experimental sample is then labeled with Cy5 and hybridized against total input DNA from the corresponding genotype, labeled in Cy3. In a single hybridization, the total input DNA serves as a baseline and is compared to the immunoprecipitated samples. Ratios of normalized signal intensities were calculated to identify enrichment of a particular sequence after immunoprecipitation, in comparison to the total input DNA. Dye swap analysis is carried out to take account of experimental variation by repeating the hybridization with identical samples labeled with Cy3 and Cy5, respectively. This SuperSeries is composed of the following subset Series: GSE1333: EV49+50, Histone 3 Lysine 4 methylation in wild-type Arabidopsis thaliana seedlings GSE1334: Histone 3 Lysine 4 methylation in ddm1 Arabidopsis thaliana seedlings GSE1335: EV104+105, Histone 3 Lysine 4 methylation in ddm1 Arabidopsis thaliana seedlings GSE1336: Ev106+107, Histone 3 Lysine 4 methylation in WT Arabidopsis thaliana seedlings GSE1337: EV51+52, Histone 3 Lysine 9 methylation in wild-type Arabidopsis thaliana seedlings GSE1338: EV59+60, Histone 3 Lysine 9 methylation in ddm1 Arabidopsis thaliana seedlings GSE1339: Histone 3 Lysine 9 methylation in wild-type Arabidopsis thaliana seedlings GSE1340: EV110+111, Histone 3 Lysine 9 methylation in ddm1 Arabidopsis thaliana seedlings Refer to individual Series