Project description:WT (MMY718) and jhd2∆ (MMY1879) sporulating cell cultures were profiled for global nucleosome occupancy using Affymetrix high-resolution tiling arrays.
Project description:RNA transcript signals were profiled in WT (MMY718) and jhd2∆ (MMY1879) terminally sporulated cultures (20h of sporulation) using Affymetrix high resolution tiling microarrays.
Project description:Low level of H3 Lys4 tri-methylation is a signature feature of silenced chromatin regions. We used microarray to analyze the contribution of S. cerevisiae H3 Lys4 demethylase Jhd2p in silenced chromatin formation process. Total RNA from two JHD2 gene altered strains : jhd2 deletion and JHD2 over-expression, together with a set1 deletion strain (Set1p: H3 Lys4 methlase) were analyzed with Affymetrix Yeast 2.0 array. We sought to dissect Jhd2p functions into H3 Lys4 methylation related and unrelated parts by comparing microarry results of JHD2 and SET1 gene altered strains.
Project description:Histone H3K4 methylation is connected to gene transcription from yeast to humans, but its mechanistic role in transcription and chromatin dynamics remains poorly understood. Here, we investigated the functions for Set1 and Jhd2, the sole H3K4 methyltransferase and H3K4 demethylase, respectively, in S. cerevisiae. Our data show that Set1 and Jhd2 predominantly co-regulate transcription. We find combined activities of Set1 and Jhd2 via H3K4 methylation contribute to positive or negative transcriptional regulation at shared target genes. Providing mechanistic insights, our data reveal that Set1 and Jhd2 together control nucleosomal occupancy during transcriptional co-regulation. Moreover, we find a remarkable genome-wide co-regulation of nucleosome and chromatin structure by Set1 and Jhd2 at different groups of transcriptionally active or inactive genes and at different regions within yeast genes. Overall, our study prompts a model wherein combined actions of Set1 and Jhd2 via H3K4 methylationâdemethylation control chromatin dynamics during various facets of transcriptional regulation. Genome-wide nucleosome maps were generated from three different yeast strains representing wild type control, set1 null and jhd2 null mutants. Three independent biological samples were grown for each strain, nucleosomes were prepared by micrococcal nuclease digestion, libraries were prepared, mononculeosomal DNA was isolated, sequenced, and analyzed separately.
Project description:Histone H3K4 methylation is connected to gene transcription from yeast to humans, but its mechanistic role in transcription and chromatin dynamics remains poorly understood. Here, we investigated the functions for Set1 and Jhd2, the sole H3K4 methyltransferase and H3K4 demethylase, respectively, in S. cerevisiae. Our data show that Set1 and Jhd2 predominantly co-regulate transcription. We find combined activities of Set1 and Jhd2 via H3K4 methylation contribute to positive or negative transcriptional regulation at shared target genes. Providing mechanistic insights, our data reveal that Set1 and Jhd2 together control nucleosomal occupancy during transcriptional co-regulation. Moreover, we find a remarkable genome-wide co-regulation of nucleosome and chromatin structure by Set1 and Jhd2 at different groups of transcriptionally active or inactive genes and at different regions within yeast genes. Overall, our study prompts a model wherein combined actions of Set1 and Jhd2 via H3K4 methylationâdemethylation control chromatin dynamics during various facets of transcriptional regulation. Genome-wide nucleosome maps were generated from three different yeast strains representing no tag control, 8V5-Set1 and Jhd2-12V5. Cells were cross-linked with formaldehyde, spheroplasted, nuclei were isolated and chromatin was prepared using micrococcal nuclease digestion, chromatin immunoprecipitation was performed using an epitope-tag specific antibody, libraries were prepared from ChIP and input DNA, sequenced, and analyzed separately.
Project description:Histone H3K4 methylation is connected to gene transcription from yeast to humans, but its mechanistic role in transcription and chromatin dynamics remains poorly understood. Here, we investigated the functions for Set1 and Jhd2, the sole H3K4 methyltransferase and H3K4 demethylase, respectively, in S. cerevisiae. Our data show that Set1 and Jhd2 predominantly co-regulate transcription. We find combined activities of Set1 and Jhd2 via H3K4 methylation contribute to positive or negative transcriptional regulation at shared target genes. Providing mechanistic insights, our data reveal that Set1 and Jhd2 together control nucleosomal occupancy during transcriptional co-regulation. Moreover, we find a remarkable genome-wide co-regulation of nucleosome and chromatin structure by Set1 and Jhd2 at different groups of transcriptionally active or inactive genes and at different regions within yeast genes. Overall, our study prompts a model wherein combined actions of Set1 and Jhd2 via H3K4 methylationâ??demethylation control chromatin dynamics during various facets of transcriptional regulation. Genome-wide nucleosome maps were generated from three different yeast strains representing no tag control, 8V5-Set1 and Jhd2-12V5. Cells were cross-linked with formaldehyde, spheroplasted, nuclei were isolated and chromatin was prepared using micrococcal nuclease digestion , chromatin immunoprecipitation was performed using an epitope-tag specific antibody, libraries were prepared from ChIP and input DNA, sequenced, and analyzed separately.
Project description:Histone H3 lysine 4 tri-methylation (H3K4me3) is a hallmark of transcription initiation, but how H3K4me3 is demethylated during gene repression is poorly understood. Jhd2, a JmjC domain protein, was recently identified as the major H3K4me3 histone demethylase (HDM) in S. cerevisiae. While JHD2 is required for removal of methylation upon gene repression, deletion of JHD2 does not result in increased levels of H3K4me3 in bulk histones, indicating that this HDM is unable to demethylate histones during steady state conditions. In this study, we showed that this was due to the negative regulation of Jhd2 activity by histone H3 lysine 14 acetylation, which co-localizes with H3K4me3 across the yeast genome. We demonstrated that loss of the histone H3-specific acetyltransferases (HATs) resulted in genome-wide-depletion of H3K4me3, and this was not due to a transcription defect. Moreover, H3K4me3 levels were reestablished in HAT mutants following loss of JHD2, which suggested that H3-specific HATs and Jhd2 served opposing functions in regulating H3K4me3 levels. We revealed the molecular basis for this suppression by demonstrating that histone H3K14 acetylation negatively regulated Jhd2 demethylase activity on an acetylated peptide in vitro. These results revealed the existence of a general mechanism for removal of H3K4me3 following gene repression. Examination of H3K4me3 in WT, ada2sas3, ada2sas3jhd2, and jhd2 strains.