Project description:RELATIVE OF EARLY FLOWERING 6 (REF6, also known as JMJ12) counteracts Polycomb mediated gene silencing through demethylating histone H3 lysine 27 trimethylation (H3K27me3) in Arabidopsis. Genome-wide analysis has demonstrated that REF6 dependent H3K37me3 demethylation occurs on hundreds of genes. However, how these genes are selectively subjected to H3K27me3 demethylation remains elusive. Here we show that a tandem array of four Cys2-His2 zinc finger domains (C2H2-ZF) at REF6 C-terminus are essential for REF6 function. Mechanistically, we find that C2H2-ZF cluster can directly recognize a specific DNA sequence motif, and is essential for binding of REF6 to its targets. In addition, we demonstrate that CUP-SHAPED COTYLEDON 1 (CUC1) and CUC3 harbor such sequence motif and are direct targets of REF6; while their close homolog, CUC2, without such binding motif is not bound by REF6. Furthermore, REF6 is essential for proper H3K27me3 level at CUC1 locus, CUC1 activation and cotyledon separation. Collectively, our study reveals not only a novel mechanism of H3K27me3 demethylase genome targeting to counteract Polycomb silencing, but also a new function of H3K27me3 demethylation in organ boundary formation. All seeds, except for H3K9me2 ChIP-seq, were grown on 1/2MS plate at 23°C under long day condition. 12 day after germination (12DAG), whole seedling were harvested for ChIP-seq. anti-HA ChIP-seq were performed with three samples: Col (WT,Negtive control), REF6-HA(REF6p::REF6-HA ref6-1),REF6-ZnF-HA(REF6p::REF6-ZnF-HA ref6-1). anti-H3K27me3 ChIP-seq were performed with four samples: Col (WT), ref6-1 (mutant), REF6-HA(REF6p::REF6-HA ref6-1),REF6-ZnF-HA(REF6p::REF6-ZnF-HA ref6-1).For H3K9me2 ChIP-seq, plants were grown in soil at 23°C under long day condition. Aerial part of plants were harvested for ChIP-seq 28d after germination.
Project description:We investigated genome wide distribution of H3K36me2, H3K36me3 and H3K27me3 in the presence and absence of MMSET protein. MMSET overexpression in t(4;14)+ myeloma leads to global loss redistribution of H3K36me2 and genome-wide loss of H3K27 methylation. Despite the gloal decrease in H3K27me3, specific regions of the genome show enhanced H3K27me3 enrichment through increased recruitment of EZH2 methyltransferase ChIP-seq for H3K36me2, H3K36me3 and H3K27me3 in two cell types
Project description:Genome-wide binding profile of PcG proteins Pho and Ph, H3K27me3 and Engrailed in Drosophila third instar larval brains and disks, in duplicate, using Illumina HiSeq 2500. The sequence reads that passed quality filters were analyzed. Drosophila third instar larval brains and disks were dissected and fixed with 2% HCHO before sonication. After sonication, chromatin immunoprecipitation using anti-Pho, -Ph, -H3K27me3, and -Engrailed antibodies was carried out.
Project description:The chromatin state in developing body parts provides a zip code to cellular populations that direct their cell fates. We used antibodies for H3K4me3, H3K27me3 and Pol2, to identify the chromatin state signature of the mouse forelimb during mid-gestation, at embryonic day 12. The families of genes marked included those related to transcription, transcriptional regulation, and embryonic organ development. Transcription factors specific for muscle development were characterized by bivalent chromatin, as E12 is a transition time point from embryonic to fetal myogenesis. The identified chromatin state of muscle specific genes was in strong correlation with their observed expression profile. Examination of the histone marks H3K4me3, H3k27me3, and Pol2 in whole E12.5 forelimnb tissues using the Illumina HiSeq 2000.
Project description:We generated maps of H3K4me1, H3K27ac (enhancers), H3K4me3, Pol II (promoters) and H3K27me3 (repressed chromatin) in the genome of human iPSC-derived cardiomyocytes Differentiation of cardiomyocytes from iPSC followed by ChIP-seq of H3K27ac, H34me1, H327me3, H3K4me3 and PolII
Project description:Dysregulation of the epigenome is a common event in malignancy. However, deciphering the earliest cancer associated epigenetic events remains a challenge. Cancer epigenome studies to date have primarily utilised cancer cell lines or clinical samples, where it is difficult to identify the initial epigenetic lesions from those that occur over time. Here, we analysed the epigenome of normal Human Mammary Epithelial Cells (HMEC) and a matched variant cell population (vHMEC) that has escaped senescence and undergone partial carcinogenic transformation. Using this model system we sought to identify the earliest epigenetic changes that potentially occur during carcinogenesis. First we show that the transcriptome of vHMEC resembles that of basal-like breast cancer. Moreover, in vHMEC there is significant deregulation of MYC, p53, EZH2/polycomb, the Aryl Hydrocarbon Receptor (AHR) and miRNAs-143, 145, 199a and 519a at the transcriptional level. Second, we find that vHMEC exhibit genome-wide changes in DNA methylation affecting key cancer-associated pathways. Hypermethylation predominately impacted gene promoters (particularly those targeted by AHR and TP53) and polycomb associated loci, whereas hypomethylation frequently affected enhancers. Next we show that long range epigenetic deregulation occurred in vHMEC involving concordant change in chromatin modification and gene expression across ~0.5-1Mb regions. Finally, we demonstrate that the DNA methylation changes we observe in vHMECs, occur in basal-like breast cancer (notably FOXA1 hypermethylation).. Overall our results suggest that the first steps of carcinogenesis are associated with a co-ordinated deregulation of DNA methylation and chromatin modification spanning a range of genomic loci potentially targeted by key transcription factors and a corresponding deregulation of transcriptional networks. We sought to study the chromatin modification profile of human mammary epithelial cells (HMEC) and a matched isogenic variant population (vHMEC) utilising ChIP-seq. ChIP was performed against H3K27ac, H3K36me3 and H3K27me3 for a HMEC and vHMEC timpoint in one donor. H3K4me3 CHIP was performed in two donors, which were treated as biological replicates.
Project description:Hox genes are essential regulators of embryonic development. They are activated in a temporal sequence following their topological order within their genomic clusters. Subsequently, states of activity are fine-tuned and maintained to translate into domains of progressively overlapping gene products. While the mechanisms underlying such temporal and spatial progressions begin to be understood, many of their aspects remain unclear. We have systematically analyzed the 3D chromatin organization of Hox clusters in vivo, during their activation using high-resolution circular chromosome conformation capture (4C-seq). Initially, Hox clusters are organized as single 3D chromatin compartments decorated with bivalent chromatin marks. Their progressive transcriptional activation is associated with a dynamic bi-modal 3D organization, whereby the genes switch one after the other, from an inactive to an active 3D compartment. These local 3D dynamics occur within a larger constitutive framework of interactions within the surrounding Topological Associated Domains, which confirms previous results that regulation of this process in primarily cluster intrinsic. The local step-wise progression in time can be stopped and memorized at various body levels and hence it may accounts for the various chromatin architectures previously described at different anterior to posterior body levels for the same embryo at a later stage. ChIP-seq samples (H3K4me3 and H3K27me3) from mouse ES cells and mouse embryonic stage E8.5 pre-somitic mesoderm. Data based on 4 biological samples.
Project description:The experiment aimed at investigating the profiles of two histone marks (H3K27me3 and H3K4me3) in muscle tissues (Pectoralis major) of 35 days-old control (n=3) and thermally-manipulated (cyclic rise in egg incubation temperature of 1.5°C from days 7 to 16 of embryogenesis; n=3) chickens.
Project description:Native-ChIP was performed to determine whether cross-linked ChIP-Seq enrichments observed at DHS exons result from co-precipitation with proximal promoter. Native ChIP-Seq was performed on H3K4me3 and H3K27me3 histone modifications in human cells
Project description:JmjC domain containing protein 14 (JMJ14) is an H3K4-specific histone demethylase that plays important roles in RNA-mediated gene silencing and flowering time regulation in Arabidopsis. However, how JMJ14 is recruited to their target genes remains unclear. Here, we show that the C-terminal FYRN and FYRC domains of JMJ14 are required for RNA silencing and flowering time regulation. Chromatin binding of JMJ14 is lost upon deletion of its FYRN and FYRC domains, along with increased H3K4me3. FYRN and FYRC domains interact with a pair of NAC domain containing transcription factors, NAC050 and NAC052. Genome-wide analysis revealed that JMJ14 and NAC050/052 share a set of common target genes with CTTGNNNNNCAAG consensus sequences. Mutations in either NAC052 or NAC050 impair RNA-mediated gene silencing. Thus, our findings demonstrate an important role of FYRN and FYRC in targeting JMJ14 through direct interaction with NAC050/052 transcription factors, which reveals a novel mechanism of recruiting a histone demethylases to its target loci in higher plants. anti-HA ChIP-seq were performed with six samples: Col, NAC050-HA, NAC052-HA, jmj14-1, JMJ14-HA and JMJ14-FYR-HA. Anti-H3K4me3 ChIP were performed with four samples: Col, jmj14-1, JMJ14-HA and JMJ14-FYR-HA. (NAC050-HA indicates PNAC050::NAC050-HA nac050-1, NAC052-HA indicates PNAC052::NAC052-HA nac052-2, JMJ14-HA indicates PJMJ14::JMJ14-HA jmj14-1, JMJ14-FYR-HA indicates PJMJ14::JMJ14-FYR-HA jmj14-1)