Project description:In higher eukaryotes, histone methylation is involved in the maintenance of cellular identity during somatic development. During spermatogenesis, most nucleosomes are replaced by protamines. Therefore, it is unclear if histone modifications function in paternal transmission of epigenetic information. Here we show that active H3K4 di-methylation (H3K4me2) and repressive H3K27 tri-methylation (H3K27me3), two modifications important for Trithorax and Polycomb-mediated gene regulation, are present in chromatin of human spermatozoa and show methylation-specific distributions at regulatory regions. H3K4me2-marked promoters control gene functions in spermatogenesis and cellular homeostasis suggesting that this mark reflects germline transcription. In contrast, H3K27me3 marks promoters of key developmental regulators in sperm as in soma. Many H3K27me3-marked genes are never expressed in the male and female germline, and in early “totipotent” embryos, suggesting a function for Polycomb in repressing somatic determinants across generations. Targets of H3K4me2 and H3K27me3 are also modified in mouse spermatozoa, implicating an evolutionary conserved role for histone methylation in chromatin inheritance via the male germline. Chromatin immuno precipitation (ChIP) was performed on sperm samples obtained from 9 normospermic donors. DNA associated with H3K4me2 or H3K27me3 was precipitated using specific antibodies. Input and precipitated DNA were amplified and hybridized to a tiling microarray (NimbleGen Systems Inc.) representing 18029 promoter regions (2200bp upstream to 500bp downstream of transcription start sites) of all RefSeq annotated human genes. For each modification 3 independent ChIP experiments were performed of which one was hybridized in a dye swap configuration.
Project description:Polycomb Repressive Complex 2 (PRC2) catalyzes histone H3 lysine 27 tri-methylation, an epigenetic modification associated with gene repression. H3K27me3 is enriched at the promoters of a large cohort of developmental genes in embryonic stem cells (ESCs). Loss of H3K27me3 leads to a failure of ESCs to properly differentiate, which presents a major roadblock for dissecting the precise roles of PRC2 activity during lineage commitment. While recent studies suggest that loss of H3K27me3 leads to changes in DNA methylation in ESCs, how these two pathways coordinate to regulate gene expression programs during lineage commitment is poorly understood. Here, we analyzed gene expression and DNA methylation levels in several PRC2 mutant ESC lines that maintain varying levels of H3K27me3. We found that maintenance of intermediate levels of H3K27me3 allowed for proper temporal activation of lineage genes during directed differentiation of ESCs to spinal motor neurons (SMNs). However, genes that function to specify other lineages failed to be repressed, suggesting that PRC2 activity is necessary for lineage fidelity. We also found that H3K27me3 is antagonistic to DNA methylation in cis. Furthermore, loss of H3K27me3 leads to a gain in promoter DNA methylation in developmental genes in ESCs and in lineage genes during differentiation. Thus, our data suggest a role for PRC2 in coordinating dynamic gene repression while protecting against inappropriate promoter DNA methylation during differentiation. Embryonic Stem Cell (ESC) lines mutant for PRC2 core components Suz12 (Suz12GT and Suz12delta) and Eed (Eednull) were subjected to in vitro directed differentiation down the spinal motor neuron lineage. ESCs and day 5 differentiated cells from the three mutant lines and wild-type were used for H3K27me3 ChIP-seq.
Project description:Polycomb Repressive Complex 2 (PRC2) catalyzes histone H3 lysine 27 tri-methylation, an epigenetic modification associated with gene repression. H3K27me3 is enriched at the promoters of a large cohort of developmental genes in embryonic stem cells (ESCs). Loss of H3K27me3 leads to a failure of ESCs to properly differentiate, which presents a major roadblock for dissecting the precise roles of PRC2 activity during lineage commitment. While recent studies suggest that loss of H3K27me3 leads to changes in DNA methylation in ESCs, how these two pathways coordinate to regulate gene expression programs during lineage commitment is poorly understood. Here, we analyzed gene expression and DNA methylation levels in several PRC2 mutant ESC lines that maintain varying levels of H3K27me3. We found that maintenance of intermediate levels of H3K27me3 allowed for proper temporal activation of lineage genes during directed differentiation of ESCs to spinal motor neurons (SMNs). However, genes that function to specify other lineages failed to be repressed, suggesting that PRC2 activity is necessary for lineage fidelity. We also found that H3K27me3 is antagonistic to DNA methylation in cis. Furthermore, loss of H3K27me3 leads to a gain in promoter DNA methylation in developmental genes in ESCs and in lineage genes during differentiation. Thus, our data suggest a role for PRC2 in coordinating dynamic gene repression while protecting against inappropriate promoter DNA methylation during differentiation. Embryonic Stem Cell (ESC) lines mutant for PRC2 core components Suz12 (Suz12GT and Suz12delta) and Eed (Eednull) were subjected to in vitro directed differentiation down the spinal motor neuron lineage. ESCs and day 5 differentiated cells from the three mutant lines and wild-type were used for Reduced Representation Bisulfite Sequencing (RRBS).
Project description:Polycomb Repressive Complex 2 (PRC2) catalyzes histone H3 lysine 27 tri-methylation, an epigenetic modification associated with gene repression. H3K27me3 is enriched at the promoters of a large cohort of developmental genes in embryonic stem cells (ESCs). Loss of H3K27me3 leads to a failure of ESCs to properly differentiate, which presents a major roadblock for dissecting the precise roles of PRC2 activity during lineage commitment. While recent studies suggest that loss of H3K27me3 leads to changes in DNA methylation in ESCs, how these two pathways coordinate to regulate gene expression programs during lineage commitment is poorly understood. Here, we analyzed gene expression and DNA methylation levels in several PRC2 mutant ESC lines that maintain varying levels of H3K27me3. We found that maintenance of intermediate levels of H3K27me3 allowed for proper temporal activation of lineage genes during directed differentiation of ESCs to spinal motor neurons (SMNs). However, genes that function to specify other lineages failed to be repressed, suggesting that PRC2 activity is necessary for lineage fidelity. We also found that H3K27me3 is antagonistic to DNA methylation in cis. Furthermore, loss of H3K27me3 leads to a gain in promoter DNA methylation in developmental genes in ESCs and in lineage genes during differentiation. Thus, our data suggest a role for PRC2 in coordinating dynamic gene repression while protecting against inappropriate promoter DNA methylation during differentiation. Embryonic Stem Cell (ESC) lines mutant for PRC2 core components Suz12 (Suz12GT and Suz12delta) and Eed (Eednull) were subjected to in vitro directed differentiation down the spinal motor neuron lineage. ESCs and day 5 differentiated cells from the three mutant lines and wild-type were used for RNA-seq.
Project description:Polycomb Repressive Complex 2 (PRC2) catalyzes histone H3 lysine 27 tri-methylation, an epigenetic modification associated with gene repression. H3K27me3 is enriched at the promoters of a large cohort of developmental genes in embryonic stem cells (ESCs). Loss of H3K27me3 leads to a failure of ESCs to properly differentiate, which presents a major roadblock for dissecting the precise roles of PRC2 activity during lineage commitment. While recent studies suggest that loss of H3K27me3 leads to changes in DNA methylation in ESCs, how these two pathways coordinate to regulate gene expression programs during lineage commitment is poorly understood. Here, we analyzed gene expression and DNA methylation levels in several PRC2 mutant ESC lines that maintain varying levels of H3K27me3. We found that maintenance of intermediate levels of H3K27me3 allowed for proper temporal activation of lineage genes during directed differentiation of ESCs to spinal motor neurons (SMNs). However, genes that function to specify other lineages failed to be repressed, suggesting that PRC2 activity is necessary for lineage fidelity. We also found that H3K27me3 is antagonistic to DNA methylation in cis. Furthermore, loss of H3K27me3 leads to a gain in promoter DNA methylation in developmental genes in ESCs and in lineage genes during differentiation. Thus, our data suggest a role for PRC2 in coordinating dynamic gene repression while protecting against inappropriate promoter DNA methylation during differentiation.
Project description:Polycomb Repressive Complex 2 (PRC2) catalyzes histone H3 lysine 27 tri-methylation, an epigenetic modification associated with gene repression. H3K27me3 is enriched at the promoters of a large cohort of developmental genes in embryonic stem cells (ESCs). Loss of H3K27me3 leads to a failure of ESCs to properly differentiate, which presents a major roadblock for dissecting the precise roles of PRC2 activity during lineage commitment. While recent studies suggest that loss of H3K27me3 leads to changes in DNA methylation in ESCs, how these two pathways coordinate to regulate gene expression programs during lineage commitment is poorly understood. Here, we analyzed gene expression and DNA methylation levels in several PRC2 mutant ESC lines that maintain varying levels of H3K27me3. We found that maintenance of intermediate levels of H3K27me3 allowed for proper temporal activation of lineage genes during directed differentiation of ESCs to spinal motor neurons (SMNs). However, genes that function to specify other lineages failed to be repressed, suggesting that PRC2 activity is necessary for lineage fidelity. We also found that H3K27me3 is antagonistic to DNA methylation in cis. Furthermore, loss of H3K27me3 leads to a gain in promoter DNA methylation in developmental genes in ESCs and in lineage genes during differentiation. Thus, our data suggest a role for PRC2 in coordinating dynamic gene repression while protecting against inappropriate promoter DNA methylation during differentiation.
Project description:Polycomb Repressive Complex 2 (PRC2) catalyzes histone H3 lysine 27 tri-methylation, an epigenetic modification associated with gene repression. H3K27me3 is enriched at the promoters of a large cohort of developmental genes in embryonic stem cells (ESCs). Loss of H3K27me3 leads to a failure of ESCs to properly differentiate, which presents a major roadblock for dissecting the precise roles of PRC2 activity during lineage commitment. While recent studies suggest that loss of H3K27me3 leads to changes in DNA methylation in ESCs, how these two pathways coordinate to regulate gene expression programs during lineage commitment is poorly understood. Here, we analyzed gene expression and DNA methylation levels in several PRC2 mutant ESC lines that maintain varying levels of H3K27me3. We found that maintenance of intermediate levels of H3K27me3 allowed for proper temporal activation of lineage genes during directed differentiation of ESCs to spinal motor neurons (SMNs). However, genes that function to specify other lineages failed to be repressed, suggesting that PRC2 activity is necessary for lineage fidelity. We also found that H3K27me3 is antagonistic to DNA methylation in cis. Furthermore, loss of H3K27me3 leads to a gain in promoter DNA methylation in developmental genes in ESCs and in lineage genes during differentiation. Thus, our data suggest a role for PRC2 in coordinating dynamic gene repression while protecting against inappropriate promoter DNA methylation during differentiation.
Project description:Genome-wide analysis of histone modification (H2AZ, H3K27ac, H3K27me3, H3K36me3, H3K4me1, H3K4me2, H3K4me3 and H3K9me3), protein-DNA binding (TAF1, P300, Pou5f1 and Nanog), cytosine methylation and transcriptome data in mouse and human ES cells and pig iPS cells We generated histone modification data (H2AZ, H3K27ac, H3K27me3, H3K36me3, H3K4me1, H3K4me2, H3K4me3 and H3K9me3) and protein-DNA binding data (TAF1, P300, Pou5f1 and Nanog) using Chromatin Immunoprecipitation followed by short sequencing (ChIP-seq), cytosine methylation data using methylated DNA immunoprecipitation followed by sequencing (MeDIP-seq) and DNA digestion by methyl-sensitive restriction enzymes followed by sequencing (MRE-seq), transcriptome data with RNA short sequencing (RNA-seq) in human embryonic stem cells, mouse embryonic stem cells, pig induced pluripotent stem cells and mouse embryonic stem cells under activin-A-induced-differentiation. Examination of 8 histone modifications, 4 protein-DNA binding, cytosine methylation and transcriptome in human embryonic stem cells, mouse embryonic stem cells, pig induced pluripotent stem cells and mouse embryonic stem cells under activin-A-induced-differentiation.
Project description:Cellular differentiation entails loss of pluripotency and parallel gain of lineage-specific and ultimately cell-type specific characteristics. Using a murine system that progresses from stem cells to lineage-committed progenitors and further to terminally differentiated neurons we analyzed two repressive epigenetic pathways: DNA methylation and Polycomb-mediated methylation of histone H3 (H3K27me3). We show that several hundred promoters become DNA methylated in lineage-committed progenitor cells. Targets are selected for pluripotency and germline-specific genes, suggesting a role for DNA methylation in stabilizing loss of pluripotency already at the progenitor state. Conversely, we detect loss and acquisition of H3K27me3 at novel targets at both progenitor and terminal state. Surprisingly, many neuron-specific genes that are poised to be activated upon terminal differentiation become Polycomb targets only in progenitor cells. Moreover, promoters marked by H3K27me3 in stem cells frequently become DNA methylated during differentiation, suggesting context-dependent crosstalk between Polycomb and DNA methylation. This data suggest a new model how de novo DNA methylation and dynamic switches in Polycomb targets restrict pluripotency and define the developmental potential of progenitor cells. Keywords: MeDIP-chip, ChIP-chip, neuronal differentiation time-course MeDIP-chip and ChIP-chip experiments were performed with at least two independnet biological replicates. For each condition hybridizations include a dye-swap experiment.
Project description:Genome-wide analysis of histone modification (H2AZ, H3K27ac, H3K27me3, H3K36me3, H3K4me1, H3K4me2, H3K4me3 and H3K9me3), protein-DNA binding (TAF1, P300, Pou5f1 and Nanog), cytosine methylation and transcriptome data in mouse and human ES cells and pig iPS cells We generated histone modification data (H2AZ, H3K27ac, H3K27me3, H3K36me3, H3K4me1, H3K4me2, H3K4me3 and H3K9me3) and protein-DNA binding data (TAF1, P300, Pou5f1 and Nanog) using Chromatin Immunoprecipitation followed by short sequencing (ChIP-seq), cytosine methylation data using methylated DNA immunoprecipitation followed by sequencing (MeDIP-seq) and DNA digestion by methyl-sensitive restriction enzymes followed by sequencing (MRE-seq), transcriptome data with RNA short sequencing (RNA-seq) in human embryonic stem cells, mouse embryonic stem cells, pig induced pluripotent stem cells and mouse embryonic stem cells under activin-A-induced-differentiation.