Mus musculus
Ontology highlight
ABSTRACT:
OTHER RELATED OMICS DATASETS IN: PXD007942
PROVIDER: PRJNA317750 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Enhancers act to regulate cell type specific gene expression by facilitating the transcription of target genes. In mammalian cells active or primed enhancers are commonly marked by monomethylation of Histone H3 at lysine 4 (H3K4me1) in a cell-type specific manner. Whether and how this histone modification regulates enhancer-dependent transcription programs in mammals has been unclear. In the present study, we conducted SILAC Mass-spec experiments with mono-nucleosomes and identified multiple H3K4me1 associated proteins, including proteins involved in chromatin remodeling. We demonstrate that H3K4me1 augments the association of the chromatin remodeling complex BAF to enhancers in vivo. Furthermore we show that in vitro, H3K4me1 nucleosomes are more efficiently remodeled by the BAF complex. Crystal structures of a BAF component BAF45c further reveal that monomethylation, but not trimethylation, is accommodated in this protein’s H3K4 binding site. Our results suggest that H3K4me1 plays an active role at enhancers by facilitating the binding of the BAF complex and possibly other chromatin regulators.
2018-10-23 | PXD007942 | Pride
Project description:Cell fate transitions involve integration of genomic information encoded by regulatory elements, such as enhancers, with the cellular environment. However, identification of the genomic sequences that control the earliest steps of human embryonic development represents a formidable challenge. Here we show that in human embryonic stem cells (hESCs) unique chromatin signatures identify two distinct classes of genomic elements, both of which are marked by the presence of chromatin regulators p300 and BRG1, and monomethylation of histone H3 at lysine 4 (H3K4me1). In addition, the elements of the first class are distinguished by the acetylation of histone H3 at lysine 27 (H3K27ac), overlap with previously characterized enhancers active in hESCs, and are generally located proximally to genes expressed in hESCs and in the epiblast. In contrast, the elements within the second class, which we termed M-bM-^@M-^\poised enhancersM-bM-^@M-^], are distinguished by the absence of H3K27ac, enrichment of histone H3 lysine 27 trimethylation (H3K27me3) and are linked to genes inactive in hESCs and involved in orchestrating early steps in mammalian development, such as gastrulation, mesoderm formation and neurulation. Consistent with the poised identity, during differentiation of hESCs to neuroepithelium, a neuroectoderm-specific subset of these elements acquires a chromatin signature associated with active enhancers. Remarkably, when assayed in zebrafish embryos, human poised enhancer elements are able to direct cell type and stage specific expression patterns characteristic of their proximal developmental gene, even in the absence of sequence conservation in the fish genome. Our data demonstrate that enhancers are epigenetically pre-marked and suggest a heretofore unappreciated role of H3K27me3 at distal regulatory elements. Moreover, the unique chromatin signature associated with poised enhancers allowed us to uncover over 2,000 putative developmental regulatory sequences, thereby creating an invaluable resource for future studies and isolation of transient, rare cell populations representing early steps of human development. For GSM602289-90: RNA-seq experiments in human ESC and neuroectodermal (NEC) speheres For GSM602291-303: Genome-wide analysis of p300, H3K4me3, H3K4me1, H3K27me3 and H3K27ac in human embryonic stem cells (ESC) and neuroectoderm cells (NEC). Additionally, in H9 ESC ChIP-seq were alsoe obtained for BRG1 and FAIRE-seq was also performed.
2010-12-15 | E-GEOD-24447 | biostudies-arrayexpress
Project description:Cell fate transitions involve integration of genomic information encoded by regulatory elements, such as enhancers, with the cellular environment. However, identification of the genomic sequences that control the earliest steps of human embryonic development represents a formidable challenge. Here we show that in human embryonic stem cells (hESCs) unique chromatin signatures identify two distinct classes of genomic elements, both of which are marked by the presence of chromatin regulators p300 and BRG1, and monomethylation of histone H3 at lysine 4 (H3K4me1). In addition, the elements of the first class are distinguished by the acetylation of histone H3 at lysine 27 (H3K27ac), overlap with previously characterized enhancers active in hESCs, and are generally located proximally to genes expressed in hESCs and in the epiblast. In contrast, the elements within the second class, which we termed “poised enhancers”, are distinguished by the absence of H3K27ac, enrichment of histone H3 lysine 27 trimethylation (H3K27me3) and are linked to genes inactive in hESCs and involved in orchestrating early steps in mammalian development, such as gastrulation, mesoderm formation and neurulation. Consistent with the poised identity, during differentiation of hESCs to neuroepithelium, a neuroectoderm-specific subset of these elements acquires a chromatin signature associated with active enhancers. Remarkably, when assayed in zebrafish embryos, human poised enhancer elements are able to direct cell type and stage specific expression patterns characteristic of their proximal developmental gene, even in the absence of sequence conservation in the fish genome. Our data demonstrate that enhancers are epigenetically pre-marked and suggest a heretofore unappreciated role of H3K27me3 at distal regulatory elements. Moreover, the unique chromatin signature associated with poised enhancers allowed us to uncover over 2,000 putative developmental regulatory sequences, thereby creating an invaluable resource for future studies and isolation of transient, rare cell populations representing early steps of human development.
2010-12-15 | GSE24447 | GEO
Project description:The integrated activity of cis-regulatory elements fine-tunes transcriptional programs of mammalian cells by recruiting cell type–specific as well as ubiquitous transcription factors (TFs). Despite their key role in modulating transcription, enhancers are still poorly characterized at the molecular level, and their limited DNA sequence conservation in evolution and variable distance from target genes make their unbiased identification challenging. The coexistence of high mono-methylation and low tri-methylation levels of lysine 4 of histone H3 is considered a signature of enhancers, but a comprehensive view of histone modifications associated to enhancers is still lacking. By combining chromatin immunoprecipitation (ChIP) with mass spectrometry, we investigated cis-regulatory regions in macrophages to comprehensively identify histone marks specifically associated with enhancers, and to profile their dynamics after transcriptional activation elicited by an inflammatory stimulation. The intersection of the proteomics data with ChIP-seq and RNA-seq analyses revealed the existence of novel subpopulations of enhancers, marked by specific histone modification signatures: specifically, H3K36me2/K4me1 marks transcribed enhancers, while H3K36me3/K4me1 and H3K79me2/K4me1 combinations mark distinct classes of intronic enhancers. Thus, our MS analysis of functionally distinct genomic regions revealed the combinatorial code of histone modifications, highlighting the potential of proteomics in addressing fundamental questions in epigenetics.
2017-10-09 | PXD007582 | Pride
Project description:We anticipated that the identification of cis-regulatory regions active in pancreatic islets would help increase our understanding of islet biology and the pathology of diabetes. Towards this end we used histone H3 lysine 4 monomethylation-based nucleosome predictions genome-wide, in conjunction with binding data for PDX1, FOXA2, MAFA, and NEUROD1, to identify 3,654 putative enhancers that are H3K4me1-enriched uniquely in islets as compared to 14 other tissue or cell-types. We show that these islet-specific enhancers are associated with genes with significantly higher islet specificity than genes associated with non-specific enhancers. Further, islet-specific enhancers were not enriched for typical active or repressive histone methylations in embryonic stem cells and liver, suggesting they are formed by de novo histone methylation during pancreas development. We also identify a subset of enhancers bivalently marked by both H3K4me1 and H3K27me3 in adult pancreatic islets. Further, we show that islet-specific enhancers triple- or quadruple- bound by PDX1, MAFA, NEUROD1 and/or FOXA2 are associated with genes with particularly high islet-specificity, and that these loci are enriched in regions with functional activity in islet cell types. Finally, we demonstrate that cytokines reduce H3K4me1 enrichment levels at selected triple- or quadruple-bound islet-specific enhancers, suggesting that epigenetic changes may contribute to cytokine-induced b-cell dysfunction. In conjunction with data from Hoffman et al Genome Research 2010, an analysis of histone modifications and transcription factor binding sites to identify enhancer regions
2011-06-30 | E-GEOD-30298 | biostudies-arrayexpress
Project description:Histone H3 lysine 4 monomethylation (H3K4me1) is an evolutionarily conserved feature of enhancer chromatin catalyzed by the COMPASS-like methyltransferase family that includes Trr in Drosophila melanogaster and MLL3 (encoded by KMT2C) and MLL4 (encoded by KMT2D) in mammals. Here we demonstrate that Drosophila embryos expressing catalytically deficient Trr eclose and develop to productive adulthood. Parallel experiments with a trr allele that augments enzyme product specificity show that conversion of H3K4me1 at enhancers to H3K4me2 and H3K4me3 is also compatible with life and results in minimal changes in gene expression. Similarly, loss of the catalytic SET domains of MLL3 and MLL4 in mouse embryonic stem cells (mESCs) does not disrupt selfrenewal. Drosophila embryos with trr alleles encoding catalytic mutants manifest subtle developmental abnormalities when subjected to temperature stress or altered cohesin levels. Collectively, our findings suggest that animal development can occur in the context of Trr or mammalian COMPASS-like proteins deficient in H3K4 monomethylation activity and point to a possible role for H3K4me1 on cis-regulatory elements in specific settings to fine-tune transcriptional regulation in response to environmental stress.
2017-10-02 | GSE95781 | GEO
Project description:Monomethylation of histone H3 at lysine 4 (H3K4me1) and acetylation of histone H3 at lysine 27 (H3K27ac) are correlated with transcriptionally engaged enhancer elements, but the functional impact of these modifications on enhancer activity is not well understood. Here we used CRISPR/Cas9 genome editing to separate catalytic activity-dependent and independent functions of Mll3 (Kmt2c) and Mll4 (Kmt2d, Mll2), the major enhancer H3K4 monomethyltransferases. Loss of Mll3/4 catalytic activity and H3K4me1 from enhancers causes partial depletion of H3K27ac, but surprisingly minor effects on enhancer Pol II binding, enhancer RNA (eRNA) transcription and gene expression. In contrast, loss of Mll3/4 proteins results in dramatic reduction of eRNA production, concomitant with impaired transcriptional elongation at adjacent promoters. Altogether our results suggest the major coactivator function of Mll3/4 is largely independent of H3K4me1 and instead linked to enhancer Pol II occupancy, eRNA transcription and long-range influence on elongation at target promoters.
2017-05-05 | GSE98063 | GEO
Project description:We anticipated that the identification of cis-regulatory regions active in pancreatic islets would help increase our understanding of islet biology and the pathology of diabetes. Towards this end we used histone H3 lysine 4 monomethylation-based nucleosome predictions genome-wide, in conjunction with binding data for PDX1, FOXA2, MAFA, and NEUROD1, to identify 3,654 putative enhancers that are H3K4me1-enriched uniquely in islets as compared to 14 other tissue or cell-types. We show that these islet-specific enhancers are associated with genes with significantly higher islet specificity than genes associated with non-specific enhancers. Further, islet-specific enhancers were not enriched for typical active or repressive histone methylations in embryonic stem cells and liver, suggesting they are formed by de novo histone methylation during pancreas development. We also identify a subset of enhancers bivalently marked by both H3K4me1 and H3K27me3 in adult pancreatic islets. Further, we show that islet-specific enhancers triple- or quadruple- bound by PDX1, MAFA, NEUROD1 and/or FOXA2 are associated with genes with particularly high islet-specificity, and that these loci are enriched in regions with functional activity in islet cell types. Finally, we demonstrate that cytokines reduce H3K4me1 enrichment levels at selected triple- or quadruple-bound islet-specific enhancers, suggesting that epigenetic changes may contribute to cytokine-induced b-cell dysfunction.
2011-06-30 | GSE30298 | GEO
Project description:Long-range chromatin interactions between enhancers and promoters are essential for transcription of many developmentally controlled genes in mammals and other metazoans. Currently, the exact mechanisms that connect distal enhancers to their specific target promoters remain to be fully elucidated. Here, we show that the enhancer-specific histone H3 lysine 4 monomethylation (H3K4me1) and the histone methyltransferases MLL3 and MLL4 (MLL3/4) play an active role in this process. We demonstrate that in differentiating mouse embryonic stem cells, MLL3/4-dependent deposition of H3K4me1 at enhancers correlates with increased levels of chromatin interactions, whereas loss of this histone modification leads to reduced levels of chromatin interactions and defects in gene activation during differentiation. H3K4me1 facilitates recruitment of the Cohesin complex, a known regulator of chromatin organization, to chromatin in vitro and in vivo, providing a potential mechanism for MLL3/4 to promote chromatin interactions between enhancers and promoters. Taken together, our results support a role for MLL3/4-dependent H3K4me1 in orchestrating long-range chromatin interactions at enhancers in mammalian cells.
2018-01-09 | GSE74055 | GEO
Project description:Host macrophage transcriptional responses to intracellular pathogens remain poorly characterized. We screened transcriptional enhancers engaged in response to M. tuberculosis (Mtb) infection by ChIPseq analysis of histone H3 lysine 4 monomethylation (H3K4me1). De novo monomethylation during infection was associated with genes implicated in host defense and apoptosis. These regions were enriched for binding sites for ETS transcription factor family members and response elements for nuclear receptors, including liver X receptors (LXRs) and peroxisomal proliferator activated receptors (PPARs), many of which were encompassed by transposable elements. LXRa expression was strongly induced by infection, whereas that of PPARs was unaffected. LXR DNA binding and NCoR corepressor recruitment increased proportionately in infected cells but coactivator association was unchanged, consistent with a lack of induction of endogenous agonists. However, treatment of infected cells with LXR agonist T0901317 strongly increased coactivator recruitment and induced a gene expression program characterized by enhanced innate immune signaling and lipid metabolism. Remarkably, T0901317 treatment selectively induced apoptosis in infected macrophages, and was accompanied by Mtb death, reducing mycobacterial burden 18-fold relative to vehicle 5d after infection. These studies define macrophage transcriptional responses to Mtb infection, and suggest that tissue-specific LXRa agonists may be efficacious in clinical management of tuberculosis.
2015-10-15 | E-MTAB-3192 | biostudies-arrayexpress